Front Speed of Language Replacement

We use two coupled equations to analyze the space-time dynamics of two interacting languages. Firstly, we introduce a cohabitation model, which is more appropriate for human populations than classical (non-cohabitation) models. Secondly, using numerical simulations we nd the front speed of a new language spreading into a region where another language was previously used. Thirdly, for a special case we derive an analytical formula that makes it possible to check the validity of our numerical simulations. Finally, as an example, we nd that the observed front speed for the spread of the English language into Wales in the period 1961-1981 is consistent with the model predictions. We also nd that the e¤ects of linguistic parameters are much more important than those of parameters related to population dispersal and reproduction. If the initial population densities of both languages are similar, they have no e¤ect on the front speed. We outline the potential of the new model to analyze relationships between language replacement and genetic replacement

Reduction in the use of diagnostic tests in infants with risk factors for early-onset neonatal sepsis does not delay antibiotic treatment

BACKGROUND: Despite a low positive predictive value, diagnostic tests such as complete blood count (CBC) and C-reactive protein (CRP) are commonly used to evaluate whether infants with risk factors for early-onset neonatal sepsis (EOS) should be treated with antibiotics. STUDY DESIGN: We investigated the impact of imple- menting a protocol aiming at reducing the number of dia- gnostic tests in infants with risk factors for EOS in order to compare the diagnostic performance of repeated clinical examination with CBC and CRP measurement. The primary outcome was the time between birth and the first dose of antibiotics in infants treated for suspected EOS. RESULTS: Among the 11,503 infants born at 35 weeks during the study period, 222 were treated with antibiotics for suspected EOS. The proportion of infants receiving an- tibiotics for suspected EOS was 2.1% and 1.7% before and after the change of protocol (p = 0.09). Reduction of dia- gnostic tests was associated with earlier antibiotic treat- ment in infants treated for suspected EOS (hazard ratio 1.58; 95% confidence interval [CI] 1.20-2.07; p <0.001), and in infants with neonatal infection (hazard ratio 2.20; 95% CI 1.19-4.06; p = 0.01). There was no difference in the duration of hospital stay nor in the proportion of infants requiring respiratory or cardiovascular support before and after the change of protocol. CONCLUSION: Reduction of diagnostic tests such as CBC and CRP does not delay initiation of antibiotic treat- ment in infants with suspected EOS. The importance of clinical examination in infants with risk factors for EOS should be emphasised.

Towards the Construction of a Multi-agent Approach for Discovering the Meaning of Natural Language Collaborative Conversations

Peer-reviewed

Mycobacterium tuberculosis Infection in Young Children: Analyzing the Performance of the Diagnostic Tests

This study evaluated the performance of the Tuberculin Skin Test (TST) and Quantiferon-TB Gold in-Tube (QFT) and the possible association of factors which may modify their results in young children (0-6 years) with recent contact with an index tuberculosis case. Materials and Methods: A cross-sectional study including 135 children was conducted in Manaus, Amazonas-Brazil. The TST and QFT were performed and the tests results were analyzed in relation to the personal characteristics of the children studied and their relationship with the index case. Results: The rates of positivity were 34.8% (TST) and 26.7% (QFT), with 14.1% of indeterminations by the QFT. Concordance between tests was fair (Kappa = 0.35 P<0.001). Both the TST and QFT were associated with the intensity of exposure (Linear OR = 1.286, P = 0.005; Linear OR = 1.161, P = 0.035 respectively) with only the TST being associated with the time of exposure (Linear OR = 1.149, P = 0.009). The presence of intestinal helminths in the TST+ group was associated with negative QFT results (OR = 0.064, P = 0.049). In the TST- group lower levels of ferritin were associated with QFT+ results (Linear OR = 0.956, P = 0.036). Conclusions: Concordance between the TST and QFT was lower than expected. The factors associated with the discordant results were intestinal helminths, ferritin levels and exposure time to the index tuberculosis case. In TST+ group, helminths were associated with negative QFT results suggesting impaired cell-mediated immunity. The TST-&QFT+ group had a shorter exposure time and lower ferritin levels, suggesting that QFT is faster and ferritin may be a potential biomarker of early stages of tuberculosis infection.

Tests of International Asset Pricing Models in Scandinavian Stock Markets

This thesis examines whether global, local and exchange risks are priced in Scandinavian countries’ equity markets by using conditional international asset pricing models. The employed international asset pricing models are the world capital asset pricing model, the international asset pricing model augmented with the currency risk, and the partially segmented model augmented with the currency risk. Moreover, this research traces estimated equity risk premiums for the Scandinavian countries. The empirical part of the study is performed using generalized method of moments approach. Monthly observations from February 1994 to June 2007 are used. Investors’ conditional expectations are modeled using several instrumental variables. In order to keep system parsimonious the prices of risk are assumed to be constant whereas expected returns and conditional covariances vary over time. The empirical findings of this thesis suggest that the prices of global and local market risk are priced in the Scandinavian countries. This indicates that the Scandinavian countries are mildly segmented from the global markets. Furthermore, the results show that the exchange risk is priced in the Danish and Swedish stock markets when the partially segmented model is augmented with the currency risk factor.

Heterogeneous products and tests for an appropriate aggregation level considering different qualities: evidence from fresh hake at Barcelona’s wholesale market

[cat] Aquest estudi destaca la importància de considerar un nivell d’agregació adequat en els anàlisis de demanda, ja que treballar utilitzant un nivell d’agregació inadequat pot donar lloc a estimacions esbiaixades. Aquest fet es mostra a través de l’anàlisi de diferents productes de lluç fresc comercialitzats a Mercabarna, el mercat majorista de Barcelona. La literatura sobre la demanda de peix tracta al lluç com un únic producte i espècie. No obstant això, en el mercat espanyol, es comercialitzen molts peixos com a lluç, els quals mostren comportaments molt diferents (des de béns inferiors fins a béns de luxe). Els resultats obtinguts, en concordança amb les observacions empíriques, demostren que l’anàlisi s’ha de realitzar amb un major grau de detall que a nivell d’espècie. Això qüestiona els resultats d’anteriors estudis de demanda i la majoria de les bases de dades, on l’observació del nivell d’agregació adequat dels productes no es té en compte.

Heterogeneous products and tests for an appropriate aggregation level considering different qualities: evidence from fresh hake at Barcelona’s wholesale market

[cat] Aquest estudi destaca la importància de considerar un nivell d’agregació adequat en els anàlisis de demanda, ja que treballar utilitzant un nivell d’agregació inadequat pot donar lloc a estimacions esbiaixades. Aquest fet es mostra a través de l’anàlisi de diferents productes de lluç fresc comercialitzats a Mercabarna, el mercat majorista de Barcelona. La literatura sobre la demanda de peix tracta al lluç com un únic producte i espècie. No obstant això, en el mercat espanyol, es comercialitzen molts peixos com a lluç, els quals mostren comportaments molt diferents (des de béns inferiors fins a béns de luxe). Els resultats obtinguts, en concordança amb les observacions empíriques, demostren que l’anàlisi s’ha de realitzar amb un major grau de detall que a nivell d’espècie. Això qüestiona els resultats d’anteriors estudis de demanda i la majoria de les bases de dades, on l’observació del nivell d’agregació adequat dels productes no es té en compte.

Profiles of Second Language Learners in Bilingual Education: A Comparative Study of the Characteristics of Finnish and American Students

The purpose of this comparative study is to profile second language learners by exploring the factors which have an impact on their learning. The subjects come from two different countries: one group comes from Milwaukee, US, and the other from Turku, Finland. The subjects have attended bilingual classes from elementary school to senior high school in their respective countries. In the United States, the subjects (N = 57) started in one elementary school from where they moved on to two high schools in the district. The Finnish subjects (N = 39) attended the same school from elementary to high school. The longitudinal study was conducted during 1994-2004 and combines both qualitative and quantitative research methods. A Pilot Study carried out in 1990-1991 preceded the two subsequent studies that form the core material of this research. The theoretical part of the study focuses first on language policies in the United States and Finland: special emphasis is given to the history, development and current state of bilingual education, and the factors that have affected policy-making in the provision of language instruction. Current language learning theories and models form the theoretical foundation of the research, and underpin the empirical studies. Cognitively-labeled theories are at the forefront, but sociocultural theory and the ecological approach are also accounted for. The research methods consist of questionnaires, compositions and interviews. A combination of statistical methods as well as content analysis were used in the analysis. The attitude of the bilingual learners toward L1 and L2 was generally positive: the subjects enjoyed learning through two languages and were motivated to learn both. The knowledge of L1 and parental support, along with early literacy in L1, facilitated the learning of L2. This was particularly evident in the American subject group. The American subjects’ L2 learning was affected by the attitudes of the learners to the L1 culture and its speakers. Furthermore, the negative attitudes taken by L1 speakers toward L2 speakers and the lack of opportunities to engage in activities in the L1 culture affected the American subjects’ learning of L2, English. The research showed that many American L2 learners were isolated from the L1 culture and were even afraid to use English in everyday communication situations. In light of the research results, a politically neutral linguistic environment, which the Finnish subjects inhabited, was seen to be more favorable for learning. The Finnish subjects were learning L2, English, in a neutral zone where their own attitudes and motivation dictated their learning. The role of L2 as a means of international communication in Finland, as opposed to a means of exercising linguistic power, provided a neutral atmosphere for learning English. In both the American and Finnish groups, the learning of other languages was facilitated when the learner had a good foundation in their L1, and the learning of L1 and L2 were in balance. Learning was also fostered when the learners drew positive experiences from their surroundings and were provided with opportunities to engage in activities where L2 was used.

Näkökulmia kielen oppimisen käytäntöihin. Turun yliopiston kielikeskus 30 vuotta - Perspectives on Language Learning in Practice. University of Turku Language Centre 30-year Celebration

Tämä julkaisu ilmestyy Turussa 18.–19.5.2009 järjestettävien valtakunnallisten kielikeskuspäivien yhteydessä. Turun yliopiston kielikeskus viettää samaan aikaan 30-vuotisjuhlaansa. Erään luokittelun mukaan 30–45-vuotias elää varsinaista keski-ikäänsä, kun taas joissakin katsotaan, että 28–35 vuoden ikä on vasta ns. jäsentymisen vaihe ja että varhainenkin keski-ikä sijoittuu vasta ikävuosiin 35–42. Voitaneen siis sanoa, että kielikeskus on ainakin ohittanut nuoruusvuodet ja on jäsentymässä tai siirtymässä keski-ikään. Tämä tuo mukanaan tietynlaista kypsymistä, itsensä varaan asettumista, imagon ja profiilin vakiintumista. Tähän kasvuun saattaa liittyä myös jonkinlainen aikuistumisen kriisi. Sen myötä kuitenkin ymmärrys lisääntyy ja oman paikan rakentaminen yliopistoyhteisössä voimistuu. Arvo- ja ajatusmaailmaan tulee uusia kehityspiirteitä: olemassaolon ja toiminnan syvemmät perustelut, illuusioiden väheneminen, hallinnan tunne, tyydytys onnistuneesta toiminnasta ja realistinen voiman tunto. Laitos esittäytyy julkaisussa 13 kirjoituksen välityksellä. Tekstit ovat sisällöltään ja käsittelytavaltaan hyvin erilaisia, mutta juuri sellaisina ne valottavat monipuolisesti laitoksen ja sen henkilökunnan toimintaa ja tuntemuksia. Kuvaukset valaisevat laitoksen erikoisluonnetta ja kuvailevat henkilökunnan erilaisia tehtäviä. Kielikeskus paljastuu dynaamisemmaksi ja heterogeenisemmaksi yksiköksi kuin ensi silmäyksellä saattaa luulla, mutta juuri siinä piilee sen voima ja rikkaus. Juhlakirjaan toivottiin kirjoituksia kielikeskuksen opetukseen tai toimintaan liittyvistä aiheista. Kirjaan sisältyy selontekojen ja kuvausten lisäksi muutamia tiukan tieteellisiä artikkeleita. Joukossa on myös joitakin esseitä, jotka koskettelevat kielen ja kulttuurin välisiä suhteita ja luovat katsauksia kielikeskuksen monikulttuuriseen arkeen. Useassa kirjoituksessa käsitellään kielipedagogisia ja -didaktisia kysymyksiä. Erityisesti tulee esiin kielikeskuksessa viime vuosina tehty uudistustyö opetuksen ja oppimisedellytysten parantamiseksi. Samalla kun muun muassa opetusteknologiaa ja kielen oppimisen käytäntöjä virtuaalisissa oppimisympäristöissä on kehitetty, opettajan rooli on muovautunut uudentyyppiseksi: perinteisen opetushenkilöstön ja muun henkilökunnan tehtävät ja toimenkuva ovat selvästi lähentyneet toisiaan. Tämä suuntaus on jatkunut jo kauan ja jatkunee tulevaisuudessakin. Kolmekymmentä viime vuotta ovat olleet yliopistossa erittäin nopean muutoksen aikaa. Tämä on näkynyt erityisesti kielikeskuksen toiminnan laajenemisessa ja kehityksessä, joissa tosin on ollut notkahduksiakin. Varsinkin nopea kansainvälistyminen, Euroopan yhteisön laajentuminen ja koko maailman avautuminen ovat tuoneet mukanaan uusia haasteita, joihin kielikeskus on heti tarttunut: kielivalikoimaa on laajennettava, kielitaitoa kohennettava ja erilaisia kulttuureja tunnettava ja ymmärrettävä syvällisemmin. Turun yliopiston kielikeskus pyrkii omalta osaltaan täyttämään nämä velvoitteet ja luomaan toiminnallaan mahdollisimman hyvät edellytykset yliopiston kansainvälistymiselle. Nämä seikat on otettu huomioon laitoksen toimintalinjojen suunnittelussa ja kehittämisessä. Kieli-ja viestintäopintojen rakenteiden uudistamista jatketaan yhteistyössä tiedekuntien kanssa. Opintojen valinnaisuutta ja vapaaehtoisuutta pyritään lisäämään sekä turvaamaan kielivalintojen monipuolisuus ja kieliosaamisen laajaalaisuus resurssien mukaan. Toimintaa kehitetään niin, että siinä otetaan entistä paremmin huomioon yhteiskunnan monikulttuuristuminen ja Euroopan komission tavoite, jonka mukaan jokaisen EU- kansalaisen tulisi osata oman äidinkielensä lisäksi vähintään kahta yhteisön kieltä. Samalla otetaan huomioon globalisaation tuomat uudet haasteet tukemalla tärkeimpien Euroopan yhteisön ulkopuolisten kielten opetusta (mm. venäjä, kiina, japani, arabia). Edelleen kielikeskus seuraa tarkoin keskustelua Suomen kielikoulutuspolitiikan perusteista ja tavoitteista ja ottaa toimintansa suunnittelussa huomioon valtakunnalliset suositukset Suomen kielikoulutuksen uudistamiseksi vastaamaan nykypäivän ja tulevaisuuden tarpeita ja tavoitteita. Se että kielikeskus on viime vuosina selvästikin vakiinnuttanut asemansa yliopiston strategisesti tärkeänä yksikkönä, ei tarkoita sitä, että nyt voitaisiin turvautua pelkästään vanhoihin toimintamalleihin ja rutiineihin. Päinvastoin, koko maailmassa, suomalaisessa yhteiskunnassa ja yliopistojen toiminnassa tapahtuneet ja tapahtuvat suuret muutokset edellyttävät kielikeskustoimintojen vireää kehittämistä ja uudistusmieltä. Laitos onkin ilmoittanut tulossopimuksessaan tukevansa opetuskokeiluja ja innovatiivisia ratkaisuja. Opettajajohtoisen opetuksen ohella on voimakkaasti kehitetty myös ohjattua itseopiskelua, monimuotoopetusta sekä vaihtoehtoisia ja uudentyyppisiä oppimismuotoja. Uutta opetusteknologiaa käytetään tehokkaasti hyväksi ja kehitetään edelleen. Opetuksessa ja ohjauksessa käytetään suomalaisten ja ulkomaisten opiskelijoiden työpanosta. Laitoksen suunnittelu- ja kehittämistyössä opiskelijat ovat toimineet viime vuosina aktiivisesti ja ansiokkaasti: yhteistyö ylioppilaskunnan kanssa toimii erinomaisesti, ja sitä on tarkoitus vielä tehostaa. Laitos on saanut runsaasti kiitosta korkealaatuisesta toiminnastaan: muun muassa v. 1998 ja 2008 Turun yliopiston vuoden opettajan palkinnon, v. 1999 Turun yliopiston parhaan koulutusyksikön palkinnon ja v. 2007 vuoden opintojaksopalkinnon. On toivottavaa, että tämä tuloksellinen työ jatkuisi ja entisestäänkin paranisi tulevina vuosina. Hyvät tulokset on saavutettu kovilla ponnistuksilla ja tiukalla sitoutumisella työhön. Aina se ei ole ollut aivan helppoa nopeiden muutosten myllerryksessä, tiukentuneessa resurssitilanteessa ja vaatimusten ja odotusten ristiriidoissa. Toivon, että pääosin hyvin sujunut yhteistyö yliopiston johdon, tiedekuntien ja opiskelijoiden kanssa sekä henkilökunnan keskuudessa voisi säilyä ja kehittyä ja että alkava vuosikymmen kielikeskuksen historiassa voisi olla entistä parempi. Hyvä yhteistyö on hyvien tulosten edellytys. Suurten uudistusten vuosi 2010 sisältää mahdollisuuden parempaan, mutta se on samalla myös riski ehkä hyvinkin paljon muuttuvassa toimintaympäristössä. Lainaan lopuksi roomalaisen historioitsijan Sallustiuksen sanat: Concordia res parvae crescunt, discordia maximae dilabuntur. Yksimielisyys saa pienetkin asiat kukoistamaan, eripura suuretkin tuhoaa. Turun yliopistolla on hyvä kielikeskus, jota kannattaa vaalia ja tukea. Kiitän kaikkia kirjoittajia ja juhlajulkaisun toimittajia Minna Maijalaa, Timo Hulkkoa ja Jane Honkaa tämän julkaisun synnystä. Samoin esitän kiitokset kielikeskuksen kirjallisen viestinnän lehtoreille, Markus Lahdelle ja Arja Lampiselle, jot ka ovat nähneet vaivaa tekstien kielellisinä korjaajina. Koko kielikeskuksen nykyistä ja aikaisempaa henkilökuntaa kiitän työstä, jota laitoksen hyväksi on tehty kuluneiden 30 vuoden aikana. Erityisen kiitoksen ansaitsee laitoksen juhlatoimikunta kaikista juhlavuoden järjestelyistä.

Is there a relationship between bilingual language switching and executive functions in bilingualism? Introducing a within-group analysis approach

Several studies have suggested a bilingual advantage in executive functions, presumably due to bilinguals' massive practice with language switching that requires executive resources, but the results are still somewhat controversial. Previous studies are also plagued by the inherent limitations of a natural groups design where the participant groups are bound to differ in many ways in addition to the variable used to classify them. In an attempt to introduce a complementary analysis approach, we employed multiple regression to study whether the performance of 30- to 75-year-old FinnishSwedish bilinguals (N = 38) on tasks measuring different executive functions (inhibition, updating, and set shifting) could be predicted by the frequency of language switches in everyday life (as measured by a language switching questionnaire), L2 age of acquisition, or by the self-estimated degree of use of both languages in everyday life. Most consistent effects were found for the set shifting task where a higher rate of everyday language switches was related to a smaller mixing cost in errors. Mixing cost is thought to reflect top-down management of competing task sets, thus resembling the bilingual situation where decisions of which language to use has to be made in each conversation. These findings provide additional support to the idea that some executive functions in bilinguals are affected by a lifelong experience in language switching and, perhaps even more importantly, suggest a complementary approach to the study of this issue.

Self-assessment of individual differences in language switching

Language switching is omnipresent in bilingual individuals. In fact, the ability to switch languages (code switching) is a very fast, efficient, and flexible process that seems to be a fundamental aspect of bilingual language processing. In this study, we aimed to characterize psychometrically self-perceived individual differences in language switching and to create a reliable measure of this behavioral pattern by introducing a bilingual switching questionnaire. As a working hypothesis based on the previous literature about code switching, we decomposed language switching into four constructs: (i) L1 switching tendencies (the tendency to switch to L1; L1-switch); (ii) L2 switching tendencies (L2-switch); (iii) contextual switch, which indexes the frequency of switches usually triggered by a particular situation, topic, or environment; and (iv) unintended switch, which measures the lack of intention and awareness of the language switches. A total of 582 SpanishCatalan bilingual university students were studied. Twelve items were selected (three for each construct). The correlation matrix was factor-analyzed using minimum rank factor analysis followed by oblique direct oblimin rotation. The overall proportion of common variance explained by the four extracted factors was 0.86. Finally, to assess the external validity of the individual differences scored with the new questionnaire, we evaluated the correlations between these measures and several psychometric (language proficiency) and behavioral measures related to cognitive and attentional control. The present study highlights the importance of evaluating individual differences in language switching using self-assessment instruments when studying the interface between cognitive control and bilingualism.

DWI and complex brain network analysis predicts vascular cognitive impairment in spontaneous hypertensive rats undergoing executive function tests

The identification of biomarkers of vascular cognitive impairment is urgent for its early diagnosis. The aim of this study was to detect and monitor changes in brain structure and connectivity, and to correlate them with the decline in executive function. We examined the feasibility of early diagnostic magnetic resonance imaging (MRI) to predict cognitive impairment before onset in an animal model of chronic hypertension: Spontaneously Hypertensive Rats. Cognitive performance was tested in an operant conditioning paradigm that evaluated learning, memory, and behavioral flexibility skills. Behavioral tests were coupled with longitudinal diffusion weighted imaging acquired with 126 diffusion gradient directions and 0.3 mm(3) isometric resolution at 10, 14, 18, 22, 26, and 40 weeks after birth. Diffusion weighted imaging was analyzed in two different ways, by regional characterization of diffusion tensor imaging (DTI) indices, and by assessing changes in structural brain network organization based on Q-Ball tractography. Already at the first evaluated times, DTI scalar maps revealed significant differences in many regions, suggesting loss of integrity in white and gray matter of spontaneously hypertensive rats when compared to normotensive control rats. In addition, graph theory analysis of the structural brain network demonstrated a significant decrease of hierarchical modularity, global and local efficacy, with predictive value as shown by regional three-fold cross validation study. Moreover, these decreases were significantly correlated with the behavioral performance deficits observed at subsequent time points, suggesting that the diffusion weighted imaging and connectivity studies can unravel neuroimaging alterations even overt signs of cognitive impairment become apparent.

First- and second-language phonological representations in the mental lexicon

Performance-based studies on the psychological nature of linguistic competence can conceal significant differences in the brain processes that underlie native versus nonnative knowledge of language. Here we report results from the brain activity of very proficient early bilinguals making a lexical decision task that illustrates this point. Two groups of SpanishCatalan early bilinguals (Spanish-dominant and Catalan-dominant) were asked to decide whether a given form was a Catalan word or not. The nonwords were based on real words, with one vowel changed. In the experimental stimuli, the vowel change involved a Catalan-specific contrast that previous research had shown to be difficult for Spanish natives to perceive. In the control stimuli, the vowel switch involved contrasts common to Spanish and Catalan. The results indicated that the groups of bilinguals did not differ in their behavioral and event-related brain potential measurements for the control stimuli; both groups made very few errors and showed a larger N400 component for control nonwords than for control words. However, significant differences were observed for the experimental stimuli across groups: Specifically, Spanish-dominant bilinguals showed great difficulty in rejecting experimental nonwords. Indeed, these participants not only showed very high error rates for these stimuli, but also did not show an error-related negativity effect in their erroneous nonword decisions. However, both groups of bilinguals showed a larger correctrelated negativity when making correct decisions about the experimental nonwords. The results suggest that although some aspects of a second language system may show a remarkable lack of plasticity (like the acquisition of some foreign contrasts), first-language representations seem to be more dynamic in their capacity of adapting and incorporating new information. &