Performance and flow dynamics studies of polymeric optofluidic sers sensors

We present a polymer-based optofluidic surface enhanced Raman scattering chip for biomolecule detection, serving as a disposable sensorchoice with cost-effective production. The SERS substrate is fabricated by using industrial roll-to-roll UV-nanoimprinting equipment andintegrated with adhesive-based polymeric microfluidics. The functioning of the SERS detection on-chip is confirmed and the effect of thepolymer lid on the obtainable Raman spectra is analysed. Rhodamine 6G is used as a model analyte to demonstrate continuous flowmeasurements on a planar SERS substrate in a microchannel. The relation between the temporal response of the sensors and sample flowdynamics is studied with varied flow velocities, using SERS and fluorescence detection. The response time of the surface-dependent SERSsignal is longer than the response time of the fluorescence signal of the bulk flow. This observation revealed the effect of convection on thetemporal SERS responses at 25 μl/min to 1000 μl/min flow velocities. The diffusion of analyte molecules from the bulk concentration intothe sensing surface induces about a 40-second lag time in the SERS detection. This lag time, and its rising trend with slower flow velocities, has to be taken into account in future trials of the optofluidic SERS sensor, with active analyte binding on the sensing surface

Reversible Heating in Electric Double Layer Capacitors

A detailed comparison is made between different viewpoints on reversible heating in electric double layer capacitors. We show in the limit of slow charging that a combined Poisson-Nernst-Planck and heat equation, first studied by d’Entremont and Pilon [J. Power Sources 246, 887 (2014)], recovers the temperature changes as predicted by the thermodynamic identity of Janssen et al. [Phys. Rev. Lett. 113, 268501 (2014)], and disagrees with the approximative model of Schiffer et al. [J. Power Sources 160, 765 (2006)] that predominates the literature. The thermal response to the adiabatic charging of supercapacitors contains information on electric double layer formation that has remained largely unexplored

Electrochemically synthesized polymers in molecular imprinting for chemical sensing

This critical review describes a class of polymers prepared by electrochemical polymerization that employs the concept of molecular imprinting for chemical sensing. The principal focus is on both conducting and nonconducting polymers prepared by electropolymerization of electroactive functional monomers, such as pristine and derivatized pyrrole, aminophenylboronic acid, thiophene, porphyrin, aniline, phenylenediamine, phenol, and thiophenol. A critical evaluation of the literature on electrosynthesized molecularly imprinted polymers (MIPs) applied as recognition elements of chemical sensors is presented. The aim of this review is to highlight recent achievements in analytical applications of these MIPs, including present strategies of determination of different analytes as well as identification and solutions for problems encountered

Selenium content of Finnish oats in 1997-1999: effect of cultivars and cultivation techniques

Se-supplemented fertilization is the main factor affecting the selenium (Se) contents of cereals in Finland. Soil and climatic conditions determine the activity of selenate added to soils and bioavailability to plants. In the present study the Se contents and its variation in Finnish oats, the differences between oat cultivars and cultivation techniques were examined. The selenium (Se) contents of oats (Avena sativa L.) in Finland were examined during 1997-1999 in 3 types of trial: official variety, organic cultivation variety and organic vs. conventional cultivation trials. Farm samples were also examined. The mean Se contents of oats in official variety trials were 0.110, 0.120 and 0.160 mg kg-1 dry weight (dw) range 0.016-0.460 mg kg-1dw in 1997-1999, respectively. The mean Se contents in farm samples were 0.050 and 0.130 mg kg-1dw in 1998 and 1999, ranging between < 0.010 and 0.330 mg kg-1 dw. Considerable regional and seasonal variations existed. The Se contents of oats were significantly higher in 1999 probably due to the combined effect of not increased fertilizer level (from 6 to 10 mg Se kg-1 fertilizer) and very low precipitation in 1999. The Se contents of oats were significantly lower in organic cultivation, due to the absence of Se-supplemented fertilization. Significant (P < 0.001) cultivar differences were detected in official variety trials. The cultivars Veli and Leila showed higher levels of Se.;Tutkimus oli osa Kaura raaka-aineen laadunohjausjärjestelmä-hanketta, jossa selvitettiin laajasti suomalaisen kauran laatua ja soveltuvuutta elintarvikeja rehukäyttöön. Tavoitteena oli selvittää kauran seleenipitoisuuksia sekä lajikkeen ja luomuviljelyn vaikutusta seleenipitoisuuksiin. Näyteaineisto koostui MTT:n tutkimusasemien ja yhteistyökumppanien kaurakokeiden satonäytteistä sekä seleeniseurantatutkimuksen yhteydessä Kasvintuotannon tarkastuskeskuksesta saaduista tilanäytteistä. Virallisissa lajikekokeissa kauran keskimääräiset seleenipitoisuudet olivat 0,110, 0,120 and 0,160 mg kg-1 kuiva-ainetta vuosina 1997-1999 vaihteluvälin ollessa 0,016-0,460 mg kg-1 kuiva-ainetta. Tilanäytteiden keskimääräiset seleenipitoisuudet olivat 0,050 and 0,130 mg kg-1 kuiva-ainetta vuosina 1998-1999, vaihteluväl

OpenDigi toimintamallin käsikirja:opettajat oppimistaitojen ja digipedagogiikan kehittäjäyhteisöissä

Abstract With the acceleration of change in society, education must also respond to the changing needs for skills. The ability to renew oneself and adapt to constant change is emerging as a new civic skill at the core of professional competence. The quality of Finnish education relies heavily on academic teacher education. Social development challenges teacher education and schools to support more strongly people’s active role as agents and instruments of change. In addition to completion of degrees, the education system must provide better opportunities for active learning. Renewal is therefore required at all levels of education. The change in education requires the professional renewal of teachers in educational institutions. Teacher education has an important role to play in this development work, not only through in-service training but also through basic training of teachers. Attention should be given to teachers’ skills and willingness to renew their competence already during their teacher studies. There is also a need for policies that support teacher educators’ own renewal. During the project entitled OpenDigi — Teachers’ communities for improving learning and digipedagogical skills, five teacher education universities, in collaboration with primary schools in their regions, created a new type of model for developing teachers’ competences based on collaborative work. The OpenDigi operating model supports the development of the skills of teacher students, teacher educators and primary teachers at different stages of their teaching careers, as well as dialogue between teacher education and primary schools. This handbook provides support for the development of Finnish education, especially for developers of teacher education and basic education. The handbook also includes individual tools and methods for teachers’ work. The handbook describes the principles of the operating model that was developed and presents three ways to apply them in relation to 1) the development of learning-to-learn skills and regional cooperation, 2) the development of digipedagogical competence, and 3) the development of research cooperation and teaching practice.Tiivistelmä Yhteiskunnallisen muutoksen kiihtyessä on muuttuneisiin osaamistarpeisiin reagoitava myös koulutuksessa. Uudeksi kansalaistaidoksi ja ammatillisen osaamisen ytimeksi on nousemassa kyky uudistua ja sopeutua jatkuvaan muutokseen. Suomalaisen koulutuksen laatu nojaa vahvasti akateemiseen opettajankoulutukseen. Yhteiskunnallinen kehitys haastaa opettajankoulutusta ja kouluja tukemaan entistä vahvemmin ihmisten aktiivista roolia muutoksen tekijöinä ja siihen sopeutujina. Tutkintojen suorittamisen lisäksi koulutusjärjestelmän tulee antaa parempia valmiuksia aktiiviseen oppimiseen. Tämä edellyttää uudistumista koulutuksen kaikilla tasoilla. Koulutuksen muutos edellyttää oppilaitoksissa toimivien opettajien ammatillista uudistumista. Opettajankoulutuksella on tässä kehitystyössä merkittävä rooli paitsi täydennyskoulutuksen myös opettajien perus-koulutuksen kautta. Opettajien taitoon ja tahtoon uudistaa omaa osaamistaan tulisi kiinnittää huomiota jo opettajaopintojen aikana. Tarvitaan myös opettajankouluttajien omaa uudistumista tukevia toimintamalleja. OpenDigi-opettajat oppimistaitojen ja digipedagogiikan kehittäjäyhteisöissä -hankkeen aikana viisi opettajankoulutusyliopistoa loivat yhteistyössä alueen peruskoulujen kanssa uudentyyppisen, yhteisölliseen työskentelyyn perustuvan, mallin opettajien osaamisen kehittämiseen. OpenDigi-toimintamalli tukee opettajan uran eri vaiheissa olevien opettajaopiskelijoiden, opettajankouluttajien ja perusasteen opettajien osaamisen kehittymistä sekä opettajankoulutuksen että perusasteen koulujen vuoropuhelua. Tämä käsikirja tarjoaa tukea suomalaisen koulutuksen kehittämiseen erityisesti opettajankoulutuksen ja perusopetuksen kehittäjille. Käsikirja sisältää myös yksittäisiä työvälineitä ja menetelmiä opettajien työhön. Käsikirjassa kuvataan kehitetyn toimintamallin periaatteet ja esitellään kolme niiden soveltamistapaa liittyen 1) oppimaan oppimisen taitojen ja alueellisen yhteistyön kehittämiseen, 2) digipedagogisen osaamisen kehittämiseen sekä 3) tutkimusyhteistyön ja opetusharjoittelun kehittämiseen

Selenium content of Finnish oats in 1997-1999: effect of cultivars and cultivation techniques

Se-supplemented fertilization is the main factor affecting the selenium (Se) contents of cereals in Finland. Soil and climatic conditions determine the activity of selenate added to soils and bioavailability to plants. In the present study the Se contents and its variation in Finnish oats, the differences between oat cultivars and cultivation techniques were examined. The selenium (Se) contents of oats (Avena sativa L.) in Finland were examined during 1997-1999 in 3 types of trial: official variety, organic cultivation variety and organic vs. conventional cultivation trials. Farm samples were also examined. The mean Se contents of oats in official variety trials were 0.110, 0.120 and 0.160 mg kg-1 dry weight (dw) range 0.016-0.460 mg kg-1dw in 1997-1999, respectively. The mean Se contents in farm samples were 0.050 and 0.130 mg kg-1dw in 1998 and 1999, ranging between < 0.010 and 0.330 mg kg-1 dw. Considerable regional and seasonal variations existed. The Se contents of oats were significantly higher in 1999 probably due to the combined effect of not increased fertilizer level (from 6 to 10 mg Se kg-1 fertilizer) and very low precipitation in 1999. The Se contents of oats were significantly lower in organic cultivation, due to the absence of Se-supplemented fertilization. Significant (P < 0.001) cultivar differences were detected in official variety trials. The cultivars Veli and Leila showed higher levels of Se.

Contents of trichothecenes in oats during official variety, organic cultivation and nitrogen fertilization trials in Finland

Natural toxins, such as mycotoxins, have emerged as a significant factor affecting the safety image of cereal grains as a raw material for the food and feed industry. The aim of the present study was to investigate the contents of trichothecenes in representative samples of oats during official variety, nitrogen fertilization and organic farming trials in Finland, 19971999. Further objectives were to promote industry and commerce by selection of high-quality oat varieties for various applications. The official variety trials conducted at 810 locations were managed following standard protocol. There were 2 types of agronomy trial, the first included comparison of oat cultivars grown in conventional and organic farming systems at 6 locations, and the second used 5 nitrogen rates (0, 40, 80, 120 and 160 kg N ha-1) at 2 locations. Regardless of wet cold summer occurring in Finland during 1998, the concentrations of Fusarium toxins were lowest during this 3 year monitoring period. More mycotoxins were produced during the warm, dry summers of 1997 and 1999 than in 1998. In all, 55% of the oat samples in the official variety trials contained deoxynivalenol (DON) within the range of 50 896 µ g kg-1. The differences in DON concentrations between organic and conventional cultivation were small. The results showed also that the use of various nitrogen fertilization levels only slightly affected the trichothecene concentrations. The contents of trichothecenes in Finnish grains appeared to be similar to or lower than those reported earlier in the Northern Hemisphere.