Food Safety Testing: Rapid Molecular Methods for Chemical and Biological Hazards

The central goal of food safety policy in the European Union (EU) is to protect consumer health by guaranteeing a high level of food safety throughout the food chain. This goal can in part be achieved by testing foodstuffs for the presence of various chemical and biological hazards. The aim of this study was to facilitate food safety testing by providing rapid and user-friendly methods for the detection of particular food-related hazards. Heterogeneous competitive time-resolved fluoroimmunoassays were developed for the detection of selected veterinary residues, that is coccidiostat residues, in eggs and chicken liver. After a simplified sample preparation procedure, the immunoassays were performed either in manual format with dissociation-enhanced measurement or in automated format with pre-dried assay reagents and surface measurement. Although the assays were primarily designed for screening purposes providing only qualitative results, they could also be used in a quantitative mode. All the developed assays had good performance characteristics enabling reliable screening of samples at concentration levels required by the authorities. A novel polymerase chain reaction (PCR)-based assay system was developed for the detection of Salmonella spp. in food. The sample preparation included a short non-selective pre-enrichment step, after which the target cells were collected with immunomagnetic beads and applied to PCR reaction vessels containing all the reagents required for the assay in dry form. The homogeneous PCR assay was performed with a novel instrument platform, GenomEra^™, and the qualitative assay results were automatically interpreted based on end-point time-resolved fluorescence measurements and cut-off values. The assay was validated using various food matrices spiked with sub-lethally injured Salmonella cells at levels of 1-10 colony forming units (CFU)/25 g of food. The main advantage of the system was the exceptionally short time to result; the entire process starting from the pre-enrichment and ending with the PCR result could be completed in eight hours. In conclusion, molecular methods using state-of-the-art assay techniques were developed for food safety testing. The combination of time-resolved fluorescence detection and ready-to-use reagents enabled sensitive assays easily amenable to automation. Consequently, together with the simplified sample preparation, these methods could prove to be applicable in routine testing.

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.

Electrochemistry and green chemical processes: electrochemical ozone production

After an introductory discussion emphasising the importance of electrochemistry for the so-called Green Chemical Processes, the article presents a short discussion of the classical ozone generation technologies. Next a revision of the electrochemical ozone production technology focusing on such aspects as: fundamentals, latest advances, advantages and limitations of this technology is presented. Recent results about fundamentals of electrochemical ozone production obtained in our laboratory, using different electrode materials (e.g. boron doped diamond electrodes, lead dioxide and DSAÒ-based electrodes) also are presented. Different chemical processes of interest to the solution of environmental problems involving ozone are discussed.

Magneto-V1: um programa para o cálculo de correções diamagnéticas e de momentos magnéticos efetivos

A new computer program has been developed to help the users of force methods for magnetic moment determination. It provides a user-friendly interface for the calculation of corrected magnetic susceptibilities of paramagnetic materials and enables the user to simulate a number of chemical formulations for the sample under study. The program is written in the Perl scripting language and runs on a Unix platform.

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.

Research on the suitability of organosolv semi-chemical triticale fibers as reinforcement for recycled hdpe composites

The main objective of this research was to study the feasibility of incorporating organosolv semi-chemical triticale fibers as the reinforcing element in recycled high density polyethylene (HDPE). In the first step, triticale fibers were characterized in terms of chemical composition and compared with other biomass species (wheat, rye, softwood, and hardwood). Then, organosolv semi-chemical triticale fibers were prepared by the ethanolamine process. These fibers were characterized in terms of its yield, kappa number, fiber length/diameter ratio, fines, and viscosity; the obtained results were compared with those of eucalypt kraft pulp. In the second step, the prepared fibers were examined as a reinforcing element for recycled HDPE composites. Coupled and non-coupled HDPE composites were prepared and tested for tensile properties. Results showed that with the addition of the coupling agent maleated polyethylene (MAPE), the tensile properties of composites were significantly improved, as compared to non-coupled samples and the plain matrix. Furthermore, the influence of MAPE on the interfacial shear strength (IFSS) was studied. The contributions of both fibers and matrix to the composite strength were also studied. This was possible by the use of a numerical iterative method based on the Bowyer-Bader and Kelly-Tyson equations

Explosion-proof requirements for Electrical Machines in Chemical, Oil and Gas Industry in Russia and CIS Countries

One of the main industries which form the basis of Russian Economical structure is oil and gas. This industry is also playing a significant role for CIS countries. Oil and gas industry is developing intensively attracting foreign investments. This situation is providing sustainable development of machinery production for hazardous areas. Operating in oil and gas areas is always related with occurrence of explosion gas atmospheres. Machines for hazardous areas must be furnished with additional protection of different types. Explosion protection is regulated with standards according to which equipment must be manufactured. In Russia and CIS countries explosion-proof equipment must be constructed in compliance with GOST standards. To confirm that equipment is manufactured according to standards’ requirements and is safe and reliable it must undergo the approval procedure. Certification in Russia is governed by Federal Laws and legislation. Each CIS country has its own approval certificates and permissions for operating in hazardous areas.

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. &

Chemical study of leaves of Chrysophyllum marginatum (Hook. & Arn.) Radlk (Sapotaceae)

The fractionation of the antioxidant ethyl acetate extract obtained from the dried leaves of Chrysophyllum marginatum afforded six substances identified as: alpha-amirin, gallic acid, myricitrin, quercitrin, (-)-epigallocatechin and (-)-epigallocatechin-3-O-gallate. This study contributes to the knowledge of the secondary metabolites produced by one more species of the Brazilian Flora, until now not investigated. Moreover, this study allowed the identification of three substances with antioxidant activity previously detected in this species.

Physico-chemical analysis of Albian (Lower Cretaceous) amber from San Just (Spain): implications for palaeoenvironmental and palaeoecological studies.

Amber from a Lower Cretaceous outcrop at San Just, located in the Eastern Iberian Peninsula (Escucha Formation, Maestrat Basin), was investigated to evaluate its physico-chemical properties. Thermogravimetric (TG) and Differential Thermogravimetric (DTG) analyses, infra-red spectroscopy, elemental and C-isotope analyses were performed. Physico-chemical differences between the internal light nuclei and the peripheral darker portions of San Just amber can be attributed to processes of diagenetic alteration that preferentially took place in the external amber border colonized by microorganisms (fungi or bacteria) when the resin was still liquid or slightly polymerized. δ13Camber values of different pieces of the same sample, from the nucleus to the external part, are remarkably homogeneous, as are δ13Camber values of the darker peripheral portions and lighter inner parts of the same samples. Hence, neither invasive microorganisms, nor diagenetic alteration, changed the bulk isotopic composition of the amber. δ13C values of different amber samples range from -21.1 to -24 , as expected for C3 plant-derived material. C-isotope analysis, coupled to palaeobotanical, TG and DTG data and infra-red spectra, suggests that San Just amber was exuded by only one conifer species, belonging to either the Cheirolepidiaceae or Aracauriaceae, coniferous families probably living under stable palaeoenvironmental and palaeoecological conditions.

Model-based study of a chemical-looping combustion process

Chemical-looping combustion (CLC) is a novel combustion technology with inherent separation of the greenhouse gas CO2. The technique typically employs a dual fluidized bed system where a metal oxide is used as a solid oxygen carrier that transfers the oxygen from combustion air to the fuel. The oxygen carrier is looping between the air reactor, where it is oxidized by the air, and the fuel reactor, where it is reduced by the fuel. Hence, air is not mixed with the fuel, and outgoing CO2 does not become diluted by the nitrogen, which gives a possibility to collect the CO2 from the flue gases after the water vapor is condensed. CLC is being proposed as a promising and energy efficient carbon capture technology, since it can achieve both an increase in power station efficiency simultaneously with low energy penalty from the carbon capture. The outcome of a comprehensive literature study concerning the current status of CLC development is presented in this thesis. Also, a steady state model of the CLC process, based on the conservation equations of mass and energy, was developed. The model was used to determine the process conditions and to calculate the reactor dimensions of a 100 MWth CLC system with bunsenite (NiO) as oxygen carrier and methane (CH4) as fuel. This study has been made in Oxygen Carriers and Their Industrial Applications research project (2008 – 2011), funded by the Tekes – Functional Material program. I would like to acknowledge Tekes and participating companies for funding and all project partners for good and comfortable cooperation.

Chemical composition of umbu (Spondias tuberosa Arr. Cam) seeds

The umbu tree (Spondias tuberosa Arr. Cam) is an important fruit tree the economy of the semi-arid northeastern region of Brazil. With the objective of finding use for the seeds, physical and chemical characterizations of the seeds from 2 cultivars in 2 maturation stages were carried out and their fatty acid and mineral profiles determined. The results showed no differences between the seeds analyzed. The yield was about 10% and the dimensions as follows: length from 1.48 to 2.11 cm and width from 0.76 to 1.16 cm. The average lipid content was 55% of which 69% was unsaturated and the average protein content was 24%. The seeds were a good source of the following minerals: P, K, Mg, Fe and Cu. The overall results indicated that the oil or the seeds could be used for food stuffs if no toxic agents were found.

A Case-based reasoning approach to validate grammatical gender and number agreement in Spanish language

Across Latin America 420 indigenous languages are spoken. Spanish is considered a second language in indigenous communities and is progressively introduced in education. However, most of the tools to support teaching processes of a second language have been developed for the most common languages such as English, French, German, Italian, etc. As a result, only a small amount of learning objects and authoring tools have been developed for indigenous people considering the specific needs of their population. This paper introduces Multilingual–Tiny as a web authoring tool to support the virtual experience of indigenous students and teachers when they are creating learning objects in indigenous languages or in Spanish language, in particular, when they have to deal with the grammatical structures of Spanish. Multilingual–Tiny has a module based on the Case-based Reasoning technique to provide recommendations in real time when teachers and students write texts in Spanish. An experiment was performed in order to compare some local similarity functions to retrieve cases from the case library taking into account the grammatical structures. As a result we found the similarity function with the best performance

Evaluation of seasonal changes in chemical composition and antibacterial activity of Elyonurus muticus (sprengel) O. Kuntze (Gramineae)

Aerial parts of Elyonurus muticus were collected in the four seasons of the year in the Brazilian Pantanal and subjected to extractrion with cold ethanol and to hydrodistillation. Sesquiterpenoids (E)-caryophyllene, bicyclogermacrene, spathulenol and caryophyllene oxide were the main components identified in the essential oils and their concentrations varied according to the plant collection period. The essential oils and the ethanolic crude extracts were active against Bacillus cereus MIP 96016, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923 and were not active against Escherichia coli ATCC 25922. The antibacterial activities varied according to the plant collection period.