875 research outputs found

    The Syntax-Pragmatics Interface: Intransitivity and Word Order in L3 Spanish

    Get PDF
    Until fairly recently, most researchers assumed that the acquisition of a second language (L2) and of a third (or subsequent) (L3/Ln) language were indistinguishable. This is not the case, as knowledge of two or more previous languages adds complexity to non-native acquisition. This study addresses the issue of crosslinguistic influence between three languages in view of two theories: (a) the L2 will always be the cause of crosslinguistic influence in an L3 (Bardel & Falk, 2012); (b) the determining factor for transfer is typological similarity between the languages in question (Rothman, 2010). This study focuses on the L3 acquisition of Spanish by speakers whose L1 is Brazilian Portuguese (BP) and L2 is English. A comparison group consisted of learners of L2 Spanish whose L1 is BP. In particular, I examined the acquisition of the choice of word order in Spanish, subject-verb or verb-subject, which depends on two factors: the type of verb (morphosyntax), and the information structure of the sentence (pragmatics), whether focused or unfocused. The problem for learners consists of processing the interface of two linguistic modules: morphosyntax and pragmatics. Interfaces have been found to be difficult in acquisition (Sorace, 2011), adding an additional wrinkle to the problem faced by learners. The three languages chosen differ in relation to word order: Portuguese distinguishes between verb types, but pragmatics is not a factor; English exhibits fixed subject-verb order; and Spanish takes both verb class and pragmatics into consideration. Because of this, we are able to distinguish between possible influence from English, which predicts rejection of verb-subject order in all circumstances, and typology, which predicts learners using verb class to distinguish word order but not pragmatics. Participants completed a preference task (Lozano, 2006), a production task, a vocabulary quiz, and a linguistic profile questionnaire. Findings support the hypothesis that typology plays a role in L3 transfer, as learners are able to adjust their interlanguage to accept the inverted order in instances where the L2 is inflexible. However, both L2 and L3 learners also seem to integrate pragmatic constraints in their interlanguage showing that they are on their way to acquiring a Spanish native-like grammar

    Variability of nuclear and mitochondrial ribosomal DNA of a truffle species (Tuber aestivum)

    Get PDF
    The intraspecific genetic variability of #Tuber aestivum$ was studied using molecular markers at various geographical scales. We used the polymerase chain reaction (PCR) coupled with restriction fragment length polymorphism (RFLP) analysis to examine the variation of the nuclear and mitochondrial ribosomal DNA (rDNA). RFLPs were found in the nuclear internal transcribed spacer (ITS) and three alleles were detected in the six populations analysed. No variability was found in mitochondrial rDNA. We found, in a very few cases, that truffles sharing different ITS genotypes could be present within a single symbiotic tree. (Résumé d'auteur

    Genetic diversity of Verticillium dahliae isolates from olive trees in Algeria

    Get PDF
    Verticillium wilt of olive trees (Olea europaea L.), a wilt caused by the soil-borne fungus Verticillium dahliae (Kleb), is one of the most serious diseases in Algerian olive groves. To assess the pathogenic and genetic diversity of olive-infecting V. dahliae populations in Algeria, orchards from the two main olive-producing regions (north-western Algeria and Kabylia) were sampled and 27 V. dahliae isolates were recovered. For purposes of comparison, V. dahliae strains from France and Syria were added to the analysis. By means of PCR primers that specifically discriminate between defoliating (D) and non-defoliating (ND) V. dahliae pathotypes it was shown that all V. dahliae isolates belonged to the ND pathotype. The amount of genetic variation between the 43 isolates was assessed by random amplification of polymorphic DNA (RAPD). A total of 16 RAPD haplotypes were found on the basis of the presence or absence of 25 polymorphic DNA fragments. Genotypic diversity between the 27 Algerian isolates was low, with two RAPD haplotypes accounting for 70% of all isolates. Genotypic diversity was however greater between isolates from Kabylia than between isolates from north-western Algeria. Cluster analysis showed that most of the Algerian V. dahliae isolates grouped together with the French and Syrian isolates. On the basis of their ability to form heterokaryons with each other, a subset of 25 olive-pathogenic isolates was grouped into a single vegetative compatibility group (VCG). These results suggest that the olive-infecting V. dahliae populations in Algeria show limited diversity and that caution should be taken to prevent introduction of the D pathotype

    Genetic diversity of Verticillium dahliae isolates from olive trees in Algeria

    Get PDF
    Summary. Verticillium wilt of olive trees (Olea europaea L.), a wilt caused by the soil-borne fungus Verticillium dahliae (Kleb), is one of the most serious diseases in Algerian olive groves. To assess the pathogenic and genetic diversity of olive-infecting V. dahliae populations in Algeria, orchards from the two main olive-producing regions (north-western Algeria and Kabylia) were sampled and 27 V. dahliae isolates were recovered. For purposes of comparison, V. dahliae strains from France and Syria were added to the analysis. By means of PCR primers that specifically discriminate between defoliating (D) and non-defoliating (ND) V. dahliae pathotypes it was shown that all V. dahliae isolates belonged to the ND pathotype. The amount of genetic variation between the 43 isolates was assessed by random amplification of polymorphic DNA (RAPD). A total of 16 RAPD haplotypes were found on the basis of the presence or absence of 25 polymorphic DNA fragments. Genotypic diversity between the 27 Algerian isolates was low, with two RAPD haplotypes accounting for 70% of all isolates. Genotypic diversity was however greater between isolates from Kabylia than between isolates from north-western Algeria. Cluster analysis showed that most of the Algerian V. dahliae isolates grouped together with the French and Syrian isolates. On the basis of their ability to form heterokaryons with each other, a subset of 25 olive-pathogenic isolates was grouped into a single vegetative compatibility group (VCG). These results suggest that the olive-infecting V. dahliae populations in Algeria show limited diversity and that caution should be taken to prevent introduction of the D pathotype

    Tuning lipase B from Candida antarctica C–C bond promiscuous activity by immobilization on poly-styrene-divinylbenzene beads

    Get PDF
    Lipase B from Candida antarctica (CALB) is able to catalyze C–C bond formation. After immobilization onto a hydrophobic PS-DVB support, the activity increases when compared to that of the soluble or tan – the commercially available Novozyme 435 (being up to 6 fold more active). Our results show that although this activity is not related to the catalytic group, the promiscuous activity of CALB may be tuned via immobilization. In addition, we have show that the secondary structure of both immobilized enzymes is quite different, using FT-ATR-IR spectroscopy

    The effectiveness evaluation of a multimedia hepatitis C prevention program for Hispanic HIV-infected individuals

    Get PDF
    Introduction—With the introduction of highly active antiretroviral therapy the Hepatitis C virus (HCV) infection has became a primary health problem among individuals suffering from HIV/ AIDS in Puerto Rico, principally those who are injecting drug users (IDUs). A multimedia educational intervention, based on the Health Beliefs Model and Social Cognitive Theory was developed and implemented to reduce HCV associated risk behaviors among IDUs. Methods—A pre- and post- intervention study evaluated the knowledge and behavioral changes in a group of HIV-infected persons recruited from February 2006 through December 2008. Results—A total of 110 participants were recruited; all were IDUs; 82% were men; 86.3% were HIV/HCV co-infected and 24.5% had active injected drugs in the last month (prior to recruitment). The group mean age was 42.2 ± 9.2 years and mean educational level was 10th grade. Knowledge of HCV risk behaviors, perception of HCV susceptibility, and perception of disease severity increased after the intervention. Knowledge of HCV clinical manifestations and HIV co-infection complications and treatment also improved. In addition, HCV risk behaviors and injecting drug practice decrease significantly among IDUs. Conclusions—This new multimedia intervention captured and maintained the participants' attention and interest, in that way facilitating their educational process. Thus, a greater of attention and interest leads to greater knowledge and prevention improvement

    Lessons Learned: Recommendations for Establishing Critical Periodic Scientific Benchmarking

    Get PDF
    The dependence of life scientists on software has steadily grown in recent years. For many tasks, researchers have to decide which of the available bioinformatics software are more suitable for their specific needs. Additionally researchers should be able to objectively select the software that provides the highest accuracy, the best efficiency and the highest level of reproducibility when integrated in their research projects. Critical benchmarking of bioinformatics methods, tools and web services is therefore an essential community service, as well as a critical component of reproducibility efforts. Unbiased and objective evaluations are challenging to set up and can only be effective when built and implemented around community driven efforts, as demonstrated by the many ongoing community challenges in bioinformatics that followed the success of CASP. Community challenges bring the combined benefits of intense collaboration, transparency and standard harmonization. Only open systems for the continuous evaluation of methods offer a perfect complement to community challenges, offering to larger communities of users that could extend far beyond the community of developers, a window to the developments status that they can use for their specific projects. We understand by continuous evaluation systems as those services which are always available and periodically update their data and/or metrics according to a predefined schedule keeping in mind that the performance has to be always seen in terms of each research domain. We argue here that technology is now mature to bring community driven benchmarking efforts to a higher level that should allow effective interoperability of benchmarks across related methods. New technological developments allow overcoming the limitations of the first experiences on online benchmarking e.g. EVA. We therefore describe OpenEBench, a novel infra-structure designed to establish a continuous automated benchmarking system for bioinformatics methods, tools and web services. OpenEBench is being developed so as to cater for the needs of the bioinformatics community, especially software developers who need an objective and quantitative way to inform their decisions as well as the larger community of end-users, in their search for unbiased and up-to-date evaluation of bioinformatics methods. As such OpenEBench should soon become a central place for bioinformatics software developers, community-driven benchmarking initiatives, researchers using bioinformatics methods, and funders interested in the result of methods evaluation.Preprin

    Development and validation of vulnerable and enabling indices for hiv viral suppression among people with hiv enrolled in the ryan white program

    Get PDF
    Background: Numerous factors impact HIV care, often requiring consideration of indices to prevent collinearity when using statistical modeling. Using the Behavioral Model for Vulnerable Populations, we developed vulnerable and enabling indices for people living with HIV (PLWH). Methods: We used Ryan White Program (RWP) data and principal component analysis to develop general and gender-and racial/ethnic-specific indices. We assessed internal reliability (Cronbach’s alpha), convergent validity (correlation coefficient), and predictive utility (logistic regression) with non-viral suppression. Results: Three general factors accounting for 79.2% of indicators’ variability surfaced: mental health, drug use, and socioeconomic status (Cronbach’s alpha 0.68). Among the overall RWP population, indices showed convergent validity and predictive utility. Using gender-or racial/ethnic-specific indices did not improve psychometric performance. Discussion: General mental health, drug use, and socioeconomic indices using administrative data showed acceptable reliability, validity, and utility for non-viral suppression in an overall PLWH population and in gender-and racial/ethnic-stratified populations. These general indices may be used with similar validity and utility across gender and racial/ethnic diverse populations

    Morbidity and mortality profile of human immunodeficiency virus-infected patients with and without hepatitis C co-infection

    Get PDF
    Purpose—Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) coinfection is an important and frequent scenario, predominantly in injecting drug users (IDUs). The present study evaluated morbidity and mortality variation in HIV infected patients with and without HCV coinfection. Methods—Coinfection prevalence was determined in 356 HIV infected persons. Their clinical manifestations, laboratory findings, risk factors, HIV therapies and mortality rates were evaluated. Results—HCV prevalence was 54% in the overall group and 81% in IDUs, with predominance of HCV genotype 1. Mortality rates were similar in patients with and without coinfection; however coinfected patients had significantly higher liver damage as a cause of mortality when compared with those who were not coinfected. Conclusions—The high HCV prevalence and the emerging mortality from liver diseases, revealed the significance of this coinfection in HIV epidemic. Primary and secondary prevention are necessary to reduce the expanding impact of HCV infection in HIV patients
    • 

    corecore