The influence of naturalistic, directionally non-specific motion on the spatial deployment of visual attention in right-hemispheric stroke

An impairment of the spatial deployment of visual attention during exploration of static (i.e., motionless) stimuli is a common finding after an acute, right-hemispheric stroke. However, less is known about how these deficits: a) are modulated through naturalistic motion (i.e., without directional, specific spatial features); and, b) evolve in the subacute/chronic post-stroke phase. In the present study, we investigated free visual exploration in three patient groups with subacute/chronic right-hemispheric stroke and in healthy subjects. The first group included patients with left visual neglect and a left visual field defect (VFD), the second patients with a left VFD but no neglect, and the third patients without neglect or VFD. Eye movements were measured in all participants while they freely explored a traffic scene without (static condition) and with (dynamic condition) naturalistic motion, i.e., cars moving from the right or left. In the static condition, all patient groups showed similar deployment of visual exploration (i.e., as measured by the cumulative fixation duration) as compared to healthy subjects, suggesting that recovery processes took place, with normal spatial allocation of attention. However, the more demanding dynamic condition with moving cars elicited different re-distribution patterns of visual attention, quite similar to those typically observed in acute stroke. Neglect patients with VFD showed a significant decrease of visual exploration in the contralesional space, whereas patients with VFD but no neglect showed a significant increase of visual exploration in the contralesional space. No differences, as compared to healthy subjects, were found in patients without neglect or VFD. These results suggest that naturalistic motion, without directional, specific spatial features, may critically influence the spatial distribution of visual attention in subacute/chronic stroke patients.

Code-switching: a touchstone of models of bilingual language production

The goal of the present thesis was to investigate the production of code-switched utterances in bilinguals’ speech production. This study investigates the availability of grammatical-category information during bilingual language processing. The specific aim is to examine the processes involved in the production of Persian-English bilingual compound verbs (BCVs). A bilingual compound verb is formed when the nominal constituent of a compound verb is replaced by an item from the other language. In the present cases of BCVs the nominal constituents are replaced by a verb from the other language. The main question addressed is how a lexical element corresponding to a verb node can be placed in a slot that corresponds to a noun lemma. This study also investigates how the production of BCVs might be captured within a model of BCVs and how such a model may be integrated within incremental network models of speech production. In the present study, both naturalistic and experimental data were used to investigate the processes involved in the production of BCVs. In the first part of the present study, I collected 2298 minutes of a popular Iranian TV program and found 962 code-switched utterances. In 83 (8%) of the switched cases, insertions occurred within the Persian compound verb structure, hence, resulting in BCVs. As to the second part of my work, a picture-word interference experiment was conducted. This study addressed whether in the case of the production of Persian-English BCVs, English verbs compete with the corresponding Persian compound verbs as a whole, or whether English verbs compete with the nominal constituents of Persian compound verbs only. Persian-English bilinguals named pictures depicting actions in 4 conditions in Persian (L1). In condition 1, participants named pictures of action using the whole Persian compound verb in the context of its English equivalent distractor verb. In condition 2, only the nominal constituent was produced in the presence of the light verb of the target Persian compound verb and in the context of a semantically closely related English distractor verb. In condition 3, the whole Persian compound verb was produced in the context of a semantically unrelated English distractor verb. In condition 4, only the nominal constituent was produced in the presence of the light verb of the target Persian compound verb and in the context of a semantically unrelated English distractor verb. The main effect of linguistic unit was significant by participants and items. Naming latencies were longer in the nominal linguistic unit compared to the compound verb (CV) linguistic unit. That is, participants were slower to produce the nominal constituent of compound verbs in the context of a semantically closely related English distractor verb compared to producing the whole compound verbs in the context of a semantically closely related English distractor verb. The three-way interaction between version of the experiment (CV and nominal versions), linguistic unit (nominal and CV linguistic units), and relation (semantically related and unrelated distractor words) was significant by participants. In both versions, naming latencies were longer in the semantically related nominal linguistic unit compared to the response latencies in the semantically related CV linguistic unit. In both versions, naming latencies were longer in the semantically related nominal linguistic unit compared to response latencies in the semantically unrelated nominal linguistic unit. Both the analysis of the naturalistic data and the results of the experiment revealed that in the case of the production of the nominal constituent of BCVs, a verb from the other language may compete with a noun from the base language, suggesting that grammatical category does not necessarily provide a constraint on lexical access during the production of the nominal constituent of BCVs. There was a minimal context in condition 2 (the nominal linguistic unit) in which the nominal constituent was produced in the presence of its corresponding light verb. The results suggest that generating words within a context may not guarantee that the effect of grammatical class becomes available. A model is proposed in order to characterize the processes involved in the production of BCVs. Implications for models of bilingual language production are discussed.

Characterization of template switching and recombination during Moloney murine leukemia virus replication

Retroviruses uniquely co-package two copies of their genomic RNA within each virion. The two copies are used as templates for synthesis of the proviral DNA during the process of reverse transcription. Two template switches are required to complete retroviral DNA synthesis by the retroviral enzyme, reverse transcriptase. With two RNA genomes present in the virion, reverse transcriptase can make template switches utilizing only one of the RNA templates (intramolecular) or utilizing both RNA templates (intermolecular) during the process of reverse transcription. The results presented in this study show that during a single cycle of Moloney murine leukemia virus replication, both nonrecombinant and recombinant proviruses predominantly underwent intramolecular minus- and plus-strand transfers during the process of reverse transcription. This is the first study to examine the nature of the required template switches occurring during MLV replication and these results support the previous findings for SNV, and the hypothesis that the required template switches are ordered events. This study also determined rates for deletion and a rate of recombination for a single cycle of MLV replication. The rates reported here are comparable to the rates previously reported for both SNV and MLV. ^

Empirical Analysis of Credit Risk Regime Switching and Temporal Conditional Default Correlation in Credit Default Swap Valuation: The Market liquidity effect

In this paper, we extend the debate concerning Credit Default Swap valuation to include time varying correlation and co-variances. Traditional multi-variate techniques treat the correlations between covariates as constant over time; however, this view is not supported by the data. Secondly, since financial data does not follow a normal distribution because of its heavy tails, modeling the data using a Generalized Linear model (GLM) incorporating copulas emerge as a more robust technique over traditional approaches. This paper also includes an empirical analysis of the regime switching dynamics of credit risk in the presence of liquidity by following the general practice of assuming that credit and market risk follow a Markov process. The study was based on Credit Default Swap data obtained from Bloomberg that spanned the period January 1st 2004 to August 08th 2006. The empirical examination of the regime switching tendencies provided quantitative support to the anecdotal view that liquidity decreases as credit quality deteriorates. The analysis also examined the joint probability distribution of the credit risk determinants across credit quality through the use of a copula function which disaggregates the behavior embedded in the marginal gamma distributions, so as to isolate the level of dependence which is captured in the copula function. The results suggest that the time varying joint correlation matrix performed far superior as compared to the constant correlation matrix; the centerpiece of linear regression models.

Joint Attention in Young Children with Autism

Autism spectrum disorders (ASDs) are classified as pervasive developmental disorders characterized by social, communicative, and behavioral impairments. According to formal and informal reports, children with ASD present with receptive and expressive language delay. Joint attention (JA: the behavior that occurs when two individuals focus on the same object or event) has been identified as a possible marker of delayed language development in children with ASD. In this study, the JA behaviors in children with ASD were contrasted with initially language-matched typically developing (TYP) children across three visits. Measures of language, the frequency, duration, and source of initiation of JA episodes, and the choice of toy during those episodes, were coded. Across visits and groups, mothers initiated more JA episodes than children; however, typical children also initiated more JA episodes than ASD children at visits 1 and 2. Also, the total duration of typically developing children’s JA episodes was generally longer than that of the ASD children’s, significantly so at Visit 2. Significant associations emerged between children’s vocabulary and two measures of JA: frequency and number of maternal initiations. Teaching parents to incorporate JA training in their interactions with their children may likely help children with ASD acquire language.

Attention-Deficit/Hyperactivity Disorder and antidepressants and prescription medications: A pilot study

Background. Attention Deficit-Hyperactivity Disorder (AD/HD) diagnosis in children and adolescents has been on the rise over the last couple of decades and a multitude of studies have been conducted in an aim to better understand the disease. Literature has explored the role of several factors suspected of contributing to development of the disease, including: prenatal smoking exposures, environmental exposures, and low-birth weight. However, there is very limited reporting of fetal/infant exposure to antidepressants and prescription medications and the long-term behavioral outcomes, namely development of AD/HD. The purpose of this study was to evaluate the relationship between mother's exposure to prescription medications and/or antidepressants around the time of conception, during pregnancy, or while breastfeeding and the development of Attention-Deficit/Hyperactivity Disorder in offspring. Methods. Secondary analysis of data from a case-control study was performed. Exposure histories were collected for the mother and offspring. Data were collected using a secure, confidential, self-report, online survey to evaluate the relationship between antidepressant and/or prescription medication exposure and the development of AD/HD. The period of exposure to these drugs was defined as: around the time of conception, during pregnancy, or while breastfeeding. Cases were defined as a child who had been diagnosed with AD/HD. Controls were defined as a child who had not been diagnosed with AD/HD. Results. Prescription medication and antidepressant medication exposures around the time of conception, during pregnancy, or while breastfeeding were not associated with development of AD/HD. However, traumatic brain injury (OR=2.77 (1.61–4.77)) and preterm birth (OR=1.48 (1.04–2.12)) were identified as potential risk factors. These results support existing literature on AD/HD, but future work must be undertaken to better evaluate fetal/infant medication exposures and long-term behavioral outcomes.^

The association of allergies and attention deficit hyperactivity disorder in children

To investigate the association between allergies and attention deficit hyperactivity disorder (ADHD), a case-control study was conducted using the National Longitudinal Survey of Youth population. Cases were between the ages of 4 and 11 years and were classified either by a maternal-reported diagnosis or by the Behavior Problems Index Hyperactivity Scale. Controls were chosen from the same age group but had a score of less than 14 on the overall Behavior Problems Index. A history of allergies was considered positive if any of the following conditions were reported as requiring treatment by a doctor or other health professional: asthma, allergic conditions, or food allergies. A strong association was observed between allergies and a maternal-reported diagnosis while controlling for demographic, socioeconomic, perinatal, and environmental factors (adjusted odds ratio = 2.85 (95% CI = 1.49-5.42)). Other risk factors found to be important risk factors for a diagnosis of ADHD were gender (male), gestational age ($<$36 weeks), and maternal education ($\leq$high school). No association between allergies and cases classified as ADHD based on the hyperactivity symptom scale was observed. This study confirms other studies that reported an allergy/ADHD association in diagnoses populations. Further investigation confirming the association and explanation of the reasons and underlying mechanisms of the observed association is warranted. These studies should use validated diagnostic criteria for the diagnosis of ADHD symptoms and allergies, adequate sample sizes, and control for confounding. ^

Attention-deficit hyperactivity disorder symptoms and lead exposure in children: A systematic review of literature

Blood lead levels > 10 µg/dL are known to affect various areas of the brain that influence behavior and cause many other health problems in children. As a result, the Centers for Disease Control and Prevention (CDC) set the blood lead action level at 10 µg/dL. However, recent research provides evidence that blood lead levels <10 µg/dL also may lead to behavioral problems in children. With the recent increase in diagnosis of Attention-Deficit Hyperactivity Disorder (ADHD) in children in the U.S. it is important to determine possible environmental toxins such as lead that may play a role in causing ADHD symptoms. The aim of this systematic review of the literature was to identify recent published studies that examine an association between blood lead levels < 10 µg/dL and ADHD symptoms in children in order to summarize their findings and describe major gaps in the literature. Although available research is limited, the articles reviewed indicate that blood lead at levels much below the CDC action level of 10 µg/dL may affect a child's level of attention, hyperactivity, impulsivity and ADHD diagnosis. Additional prospective research is warranted in order to inform the revision of current blood lead action levels as well as better elucidate the relationship between lead and ADHD diagnoses.^

Un elixir de la palabra : Heterogeneidad interlingüe en la narrativa de Sandra Cisneros

Esta tesis doctoral explora la construcción de algunos aspectos enunciativos relacionados con la heterogeneidad lingüístico-cultural presentes en la narrativa de la escritora chicana Sandra Cisneros [n. 1954]. Más específicamente, esta investigación tiene como objetivo principal explicar el fenómeno de la desterritorialización de la lengua a partir del examen de la conformación de espacios lingüístico-culturales intersticiales a lo largo del desarrollo de la obra de Cisneros [1984, 1991, 2002], que conforma el corpus de nuestro trabajo. Nuestra hipótesis rectora indica que en la escritura de Cisneros. La constitución de la heterogeneidad y la gesta del sentido son ineludiblemente interlingües. Así, proponemos que la heterogeneidad interlingüe es la categoría que permite explicar la complejidad discursivo-enunciativa característica de nuestro corpus. A partir del concepto de heterogeneidad[es] enunciativa[s] elaborado por Authier-Revuz [1984]. Definimos la heterogeneidad interlingüe como un fenómeno enunciativo que se inscribe en el ámbito del dialogismo interdiscursivo [Bajtin [1952-3] 1982] y que se manifiesta a través de las marcas y formas que surgen en el discurso a través de los procesos de negociación y traducción Iingüistico-culturales actualizados en el encuentro constante y constitutivo de distintas lenguas. Según entendemos, la heterogeneidad interlingüe se articula a partir de tres dimensiones que se encuentran en permanente interacción: la conformación de una imagen discursiva o ethos [Ducrot, [1984] 1986; Amossy, 1999] asociado al responsable de la enunciación de la totalidad de los textos narrativos [Iocutor-Autor], la institución de sitios -formas y marcas- que se presentan como heterogéneos desde un punto de vista lingüístico-cultural y la configuración de una practica de lectura particular que exige una competencia discursivo-cultural de parte del lector que debe completar el sentido del texto y también del discurso. En atención alas dimensiones aludidas, esta tesis otorga atención específica a los siguientes aspectos: la constitución interlingüe de la paratextualidad, la alternancia de lenguas, los distintos modos de presencia de la traducción, los enunciados paremiológicos y la dimensión reflexiva de la enunciación. Entre los objetivos centrales de nuestra investigación, se cuentan: 1. la elaboración de un andamiaje teórico-metodológico pluridisciplinario que permita dar cuenta de las particularidades discursivas de nuestro corpus y ser referencia para el análisis de otras escrituras de minorías y narrativas de frontera; 2. la contribución al desarrollo de los estudios del discurso [Authier-Revuz, 1984, 1995; Ducrot. [1984] 1986, 2004] a través de la incorporación de la noción de interlingüismo a la discusión de la constitución de la heterogeneidad y de la gesta del sentido discursivo; 3. la articulación del concepto de desterritorializacion [Deleuze y Guattari, [1975] 1998] con algunas nociones originadas en los modelos provenientes de la teoría de la Frontera [Hicks, 1991; Arteaga, 1997] y de la teoría discursiva de Authier-Revuz [1984, 1995]. En cuanto a los objetivos particulares, este trabajo de tesis se propone examinar las distintas formas y marcas de la heterogeneidad interlingüe presentes en la narrativa de Cisneros y ofrecer un panorama analítico que pondere la evolución de la obra de la escritora chicana en relación con la construcción del responsable de la enunciación, los sitios de la heterogeneidad y la practica de lectura singular que impone esta escritura

Un elixir de la palabra : Heterogeneidad interlingüe en la narrativa de Sandra Cisneros

Esta tesis doctoral explora la construcción de algunos aspectos enunciativos relacionados con la heterogeneidad lingüístico-cultural presentes en la narrativa de la escritora chicana Sandra Cisneros [n. 1954]. Más específicamente, esta investigación tiene como objetivo principal explicar el fenómeno de la desterritorialización de la lengua a partir del examen de la conformación de espacios lingüístico-culturales intersticiales a lo largo del desarrollo de la obra de Cisneros [1984, 1991, 2002], que conforma el corpus de nuestro trabajo. Nuestra hipótesis rectora indica que en la escritura de Cisneros. La constitución de la heterogeneidad y la gesta del sentido son ineludiblemente interlingües. Así, proponemos que la heterogeneidad interlingüe es la categoría que permite explicar la complejidad discursivo-enunciativa característica de nuestro corpus. A partir del concepto de heterogeneidad[es] enunciativa[s] elaborado por Authier-Revuz [1984]. Definimos la heterogeneidad interlingüe como un fenómeno enunciativo que se inscribe en el ámbito del dialogismo interdiscursivo [Bajtin [1952-3] 1982] y que se manifiesta a través de las marcas y formas que surgen en el discurso a través de los procesos de negociación y traducción Iingüistico-culturales actualizados en el encuentro constante y constitutivo de distintas lenguas. Según entendemos, la heterogeneidad interlingüe se articula a partir de tres dimensiones que se encuentran en permanente interacción: la conformación de una imagen discursiva o ethos [Ducrot, [1984] 1986; Amossy, 1999] asociado al responsable de la enunciación de la totalidad de los textos narrativos [Iocutor-Autor], la institución de sitios -formas y marcas- que se presentan como heterogéneos desde un punto de vista lingüístico-cultural y la configuración de una practica de lectura particular que exige una competencia discursivo-cultural de parte del lector que debe completar el sentido del texto y también del discurso. En atención alas dimensiones aludidas, esta tesis otorga atención específica a los siguientes aspectos: la constitución interlingüe de la paratextualidad, la alternancia de lenguas, los distintos modos de presencia de la traducción, los enunciados paremiológicos y la dimensión reflexiva de la enunciación. Entre los objetivos centrales de nuestra investigación, se cuentan: 1. la elaboración de un andamiaje teórico-metodológico pluridisciplinario que permita dar cuenta de las particularidades discursivas de nuestro corpus y ser referencia para el análisis de otras escrituras de minorías y narrativas de frontera; 2. la contribución al desarrollo de los estudios del discurso [Authier-Revuz, 1984, 1995; Ducrot. [1984] 1986, 2004] a través de la incorporación de la noción de interlingüismo a la discusión de la constitución de la heterogeneidad y de la gesta del sentido discursivo; 3. la articulación del concepto de desterritorializacion [Deleuze y Guattari, [1975] 1998] con algunas nociones originadas en los modelos provenientes de la teoría de la Frontera [Hicks, 1991; Arteaga, 1997] y de la teoría discursiva de Authier-Revuz [1984, 1995]. En cuanto a los objetivos particulares, este trabajo de tesis se propone examinar las distintas formas y marcas de la heterogeneidad interlingüe presentes en la narrativa de Cisneros y ofrecer un panorama analítico que pondere la evolución de la obra de la escritora chicana en relación con la construcción del responsable de la enunciación, los sitios de la heterogeneidad y la practica de lectura singular que impone esta escritura

The attention/support to students in the socio-labor transition

In the present paper I intend to put forward some inquiries regarding the socio-labor guidance and transition of the young people in the co-ordinates of contemporary society. The outstanding paradox in which some young people are immersed when trying to get a first, second, third employment is also analyzed: "The job of looking for a job". This is a common experience shared by many young people when they try to find a place in the complex labor panorama. Looking for a job is a recurrent situation in contemporary society, given the high dose of precarious employment in which the productive world moves. Life-long jobs belong to the past and what is normal is that people strive to enter the competitive labor market repeatedly. Moreover, the paper offers the partial results of a larger research project that approaches tutorship, decision taking and expectations before the academic-labor future of the studentship in the last years of secondary school. Finally, I suggest some insights in the line that it is not longer feasible to work with old-fashioned guidance, trying to channel people's vocation and offering them information so that they get a job that provides them with the happiness of "doing what you like". Behind these ideas lay the normal biographies, the predictable itineraries. Labor market complexity makes the transition to working life very difficult. Once immersed in it, biographies and labor itineraries are constructed and reconstructed at the rhythm of the changing fortunes of times.

Un elixir de la palabra : Heterogeneidad interlingüe en la narrativa de Sandra Cisneros

Esta tesis doctoral explora la construcción de algunos aspectos enunciativos relacionados con la heterogeneidad lingüístico-cultural presentes en la narrativa de la escritora chicana Sandra Cisneros [n. 1954]. Más específicamente, esta investigación tiene como objetivo principal explicar el fenómeno de la desterritorialización de la lengua a partir del examen de la conformación de espacios lingüístico-culturales intersticiales a lo largo del desarrollo de la obra de Cisneros [1984, 1991, 2002], que conforma el corpus de nuestro trabajo. Nuestra hipótesis rectora indica que en la escritura de Cisneros. La constitución de la heterogeneidad y la gesta del sentido son ineludiblemente interlingües. Así, proponemos que la heterogeneidad interlingüe es la categoría que permite explicar la complejidad discursivo-enunciativa característica de nuestro corpus. A partir del concepto de heterogeneidad[es] enunciativa[s] elaborado por Authier-Revuz [1984]. Definimos la heterogeneidad interlingüe como un fenómeno enunciativo que se inscribe en el ámbito del dialogismo interdiscursivo [Bajtin [1952-3] 1982] y que se manifiesta a través de las marcas y formas que surgen en el discurso a través de los procesos de negociación y traducción Iingüistico-culturales actualizados en el encuentro constante y constitutivo de distintas lenguas. Según entendemos, la heterogeneidad interlingüe se articula a partir de tres dimensiones que se encuentran en permanente interacción: la conformación de una imagen discursiva o ethos [Ducrot, [1984] 1986; Amossy, 1999] asociado al responsable de la enunciación de la totalidad de los textos narrativos [Iocutor-Autor], la institución de sitios -formas y marcas- que se presentan como heterogéneos desde un punto de vista lingüístico-cultural y la configuración de una practica de lectura particular que exige una competencia discursivo-cultural de parte del lector que debe completar el sentido del texto y también del discurso. En atención alas dimensiones aludidas, esta tesis otorga atención específica a los siguientes aspectos: la constitución interlingüe de la paratextualidad, la alternancia de lenguas, los distintos modos de presencia de la traducción, los enunciados paremiológicos y la dimensión reflexiva de la enunciación. Entre los objetivos centrales de nuestra investigación, se cuentan: 1. la elaboración de un andamiaje teórico-metodológico pluridisciplinario que permita dar cuenta de las particularidades discursivas de nuestro corpus y ser referencia para el análisis de otras escrituras de minorías y narrativas de frontera; 2. la contribución al desarrollo de los estudios del discurso [Authier-Revuz, 1984, 1995; Ducrot. [1984] 1986, 2004] a través de la incorporación de la noción de interlingüismo a la discusión de la constitución de la heterogeneidad y de la gesta del sentido discursivo; 3. la articulación del concepto de desterritorializacion [Deleuze y Guattari, [1975] 1998] con algunas nociones originadas en los modelos provenientes de la teoría de la Frontera [Hicks, 1991; Arteaga, 1997] y de la teoría discursiva de Authier-Revuz [1984, 1995]. En cuanto a los objetivos particulares, este trabajo de tesis se propone examinar las distintas formas y marcas de la heterogeneidad interlingüe presentes en la narrativa de Cisneros y ofrecer un panorama analítico que pondere la evolución de la obra de la escritora chicana en relación con la construcción del responsable de la enunciación, los sitios de la heterogeneidad y la practica de lectura singular que impone esta escritura