Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti, from 30 countries in six continents and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya) the two subspecies remain genetically distinct whereas in urban settings they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats, and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th Centuries was followed by its introduction to Asia in the late 19th Century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l.. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for methods using genetic modification of populations.

Background. After decades of obscurity, Zika virus (ZIKV) has spread through the Americas since 2015 accompanied by congenital microcephaly and Guillain-Barré syndrome. Although these epidemics presumably involve transmission by Aedes aegypti, no direct evidence of vector involvement has been reported, prompting speculation that other mosquitoes such as Culex quinquefasciatus could be involved.Methods. We detected an outbreak of ZIKV infection in southern Mexico in late 2015. Sera from suspected ZIKV-infected patients were analyzed for viral RNA and antibodies. Mosquitoes were collected in and around patient homes and tested for ZIKV.Results. Of 119 suspected ZIKV-infected patients, 25 (21%) were confirmed by RT-PCR of serum collected 1-8 days after the onset of signs and symptoms including rash, arthralgia, headache, pruritus, myalgia, and fever. Of 796 mosquitoes collected, A. aegypti yielded ZIKV detection by RT-PCR in 15 of 55 pools (27.3%). No ZIKV was detected in C. quinquefasciatus. ZIKV sequences derived from sera and mosquitoes showed a monophyletic relationship suggestive of a point source introduction from Guatemala.Conclusions. These results demonstrate the continued, rapid northward progression of ZIKV into North America with typically mild disease manifestations, and implicate A. aegypti for the first time as a principal vector in North America.

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Emotional words are increasingly used in the study of word processing. To elucidate whether the experimental effects obtained with these words are due either to their affective content or to other semantic characteristics, it is necessary to conduct experiments with affectively valenced words obtained from different semantic categories. In the present article, we present affective ratings for 380 Spanish words belonging to three semantic categories: animals, people, and objects. The norms are based on the assessments made by 504 participants, who rated about 47 words either in valence and arousal, by using the Self-Assessment Manikin (Bradley & Lang, Journal of Behavioral Therapy and Experimental Psychiatry, 25, 49-59. 1994), or in concreteness and familiarity. These ratings will help researchers select stimuli for experiments in which both the affective properties of words and their membership to a given semantic category have to be taken into account. The database is available as an online supplement for this article.

NIM is Web-based software developed to help experimenters with some of the usual tasks carried out in psycholinguistic studies. It allows the user to search for words according to several variables, such as length, matching substrings, lexical frequency, or part of speech, in English, Spanish, and Catalan. NIM also provides the user with the possibilities to obtain different word metrics, such as lexical frequency, length, and part of speech; to find intralanguage and cross-language lexical neighbors; and to get control words for critical stimuli. Regardless of the language used, the program also enables the user to get the orthographic similarity between word pairs and to identify repeated items in lists of experimental stimuli. NIM is free and is publicly available at

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The present study investigates the developmental aspect of the revised hierarchical model (Kroll & Stewart, 1994) concerning the access to the conceptual store from the second language (L2). We manipulated the level of proficiency and age of L2 acquisition. We tested SpanishCatalan bilinguals (49 early proficient bilinguals, 28 late proficient bilinguals, and 28 late nonproficient bilinguals) in a translation recognition task in which they had to decide whether the second of two words was the correct translation of the first. The second word of the pair could be the true translation, a word related in form, a word more or less related in meaning, or an unrelated word. The results showed that both early and late proficient bilinguals were more sensitive to the semantic than to

Link to this article: http://journals.cambridge.org/abstract_S1366728909990393 How to cite this article: CHRIS DAVIS, ROSA SÁNCHEZ-CASAS, JOSÉ E. GARCÍA-ALBEA, MARC GUASCH, MARGARITA MOLERO and PILAR FERRÉ (2010). Masked translation priming: Varying language experience and word type with Spanish-English bilinguals. Bilingualism: Language and Cognition, 13, pp 137-155Spanish-English bilingual lexical organization was investigated using masked cognate and non-cognate priming with the lexical decision task. In Experiment 1, three groups of bilinguals (Spanish dominant, English dominant and Balanced) and a single group of beginning bilinguals (Spanish) were tested with Spanish and English targets primed by cognate and non-cognate translations. All the bilingual groups showed cognate but not non-cognate priming. This cognate priming effect was similar in magnitude to the within-language repetition priming effect; it did not vary across participants who had different second-language acquisition histories, nor was the size of the priming effect modulated by the direction of the translation. The beginning bilingual group only showed cognate priming when the primes were in Spanish (L1) and the targets in English (L2). In Experiment 2, both form-related and unrelated word baselines were used with a single group of bilinguals. The results were the same as Experiment 1: cognate priming and no non-cognate priming. Experiment 3 examined the cognate priming effect with reduced orthographic and phonological overlap. Despite this reduced form overlap, it was found that the cognate effect was the same size as the within-language repetition effect. These results indicate that cognate translations are special and ways of modifying models of bilingual lexical processing to reflect this were considered.