Cooling of suspended nanostructures with tunnel junctions

We have investigated electronic cooling of suspended nanowires with SINIS tunnel junction coolers. The suspended samples consist of a free standing nanowire suspended by four narrow ($\sim$ 200 nm) bridges. We have compared two different cooler designs for cooling the suspended nanowire. We demonstrate that cooling of the nanowire is possible with a proper SINIS cooler design

Ohjelmoitu opetus

Alkusanoissa todetaan, että "Nykyisen yhteiskunnan valtavasti lisääntynyt koulutustarve on pakottanut tutkimuksiin uusien ja tehokkaampien opetusmenetelmien kehittämiseen. teknillistyvät taisteluvälineet, uudet taistelumenetelmät ja nopeasti alkavan sodan mahdollisuus asettavat myös sotilaskoulutukselle uusia vaatimuksia." Artikkelin tarkoituksena on selvittää eri maissa esitettyjen teorioiden ja muun aineiston perusteella, mitä on ohjelmoitu opetus. Ensimmäisessä luvussa käsitellään ohjelmoidun opetuksen teoreettista perustaa ja eräitä ohjelmoituun opetukseen liittyviä oppimispsykologisia käsitteitä. Toisessa luvussa tarkastellaan ohjelmatyyppejä ja ohjelmoidun opintomateriaalin laatimisen yleisiä periaatteita. Kolmannessa luvussa käsitellään ohjelmoidun opetusaineiston esittämisvälineitä ja niiden soveltuvuutta sotilaskoulutukseen. Siinä esitellään opetuskoneet ja käsitellään tietokoneohjattua opetusta, ohjelmoitua oppikirjaa, television hyödyntämistä, kielistudiota sekä simulaattoreita. Neljännessä luvussa, "Ohjelmoidun opetuksen sopivuus sotilaskoulutukseen", esitellään aluksi ohjelmoidun opetuksen asemaa eräiden maiden sotilaskoulutuksessa sekä tarkastellaan tutkimuksista ja kokeiluista saatuja tuloksia. Yhdistelmässä todetaan, että "Sotilaskoulutuksessa ei kuitenkaan liene syytä odottaa siviilipiireissä tapahtuvaa kehitystä, vaan on pyrittävä mahdollisimman nopeasti käyttämään muissa maissa saatuja tutkimusten tuloksia."There is summary in English at the end of the article

Reversible control of the electronic density of states at the Fermi level of Ca3Co4O9+δ misfit-layered oxide single crystals through O+/H+ plasma exposure

Misfit-layered Ca3Co4O9 crystals were grown and characterized via XRD, SEM, and photo-emission spectroscopy (PES). The evolution of the intensity at the Fermi level (E F) with varying oxygen content was studied by PES. Oxygen species were successfully introduced and removed through O+ and H+ microwave-plasma (2.45GHz, 2-5mbar) treatments, respectively. A 5min O+ plasma exposure was observed to result into a drastic enhancement in the E F intensity, demonstrating the influence of oxygen content to the charge carrier population in layered cobalt-oxide material

Suomalaisten opettajien asenteita ja valmiuksia ohjelmoinnin opetukseen

Tiivistelmä. Tässä pro gradu -tutkielmassa tarkastellaan suomalaisten perusopetuksen opettajien valmiuksia opettaa ohjelmointia sekä asenteita ohjelmoinnin opettamista kohtaan. Lähtökohtana tutkielmalle on uusi Perusopetuksen opetussuunnitelman perusteet ja sen mukanaan tuoma ohjelmoinnin opetuksen sisällyttäminen opetukseen. Pro gradun teoreettinen osa ja sen pohjalta laadittu mittaristo perustuu kahteen pääteoriaan. Tutkielmassa kerätty aineisto on avointa ja se on kaikkien käytettävissä Aalto-yliopiston kautta. Aineistonkeruun instrumentissa opettajien teknologia-asenteen taustalla ovat Davisin (1989) teknologian hyväksymismalli (Technology Acceptance Model, TAM) sekä Venkatesh et al. (2003) Yhdistetty teoria teknologian hyväksymisestä ja käytöstä (Unified Theory of Acceptance and Use of Technology, UTAUT). Tutkielmassa on tarkoituksena tarkastella suomalaisen perusopetuksen opettajan valmiuksia opettaa ohjelmointia sekä asenteita niin ohjelmoinnin asemasta perusopetuksessa, kuin ohjelmoinnin opetuksesta yleisesti. Työn tuloksien avulla pyritään kehittämään suomalaisten peruskoulun opettajien koulutusta ohjelmoinnin opetuksessa. Pro gradu tutkielman aineisto on kerätty yhteistyössä koodiaapinen.fi-sivuston ohjelmointikurssin kanssa. Tutkimuskysely järjestettiin kurssin osallistujille. Tutkielma perustuu 317 suomalaisen opettajan web-kyselylomakkeeseen. Tutkielman päätulokset: Noin yksi kymmenestä vastaajasta ilmoitti pystyvänsä opettamaan joitakin seuraavista kielistä: Scratch, Scratch Jr., Code.org, ja HTML/CSS. Muiden ohjelmointikielten ja -ympäristöjen osaajia oli merkittävästi vähemmän. Uskoa ohjelmoinnin opettamisen osaamiseen vastaajien keskuudessa kuitenkin on, sillä lähes puolet vastaajista ilmoitti pystyvänsä ratkaisemaan ohjelmoinnin opetuksen ongelmia, vaikka paikalla ei olisi ketään ohjeistamassa ja yli 70 % vastaajasta ilmoitti pystyvänsä ratkaisemaan ohjelmoinnin opetuksen ongelmia, jos käytettävissä on runsaasti (riittävästi) aikaa. Ohjelmoinnin opettaminen peruskoulussa nähdään tarpeellisena vastaajien keskuudessa. 74,1 % on osittain samaa mieltä tai täysin samaa mieltä väittämän ”Ohjelmoinnin opettamista tarvitaan peruskoulussa”. Suomalaisten opettajien suhtautuminen ohjelmoinnin opettamiseen on hieman neutraalia positiivisempi tai opettajat eivät tiedä miten he asennoituvat ohjelmointia kohtaan. Yleinen suhtautuminen ja ahdistuksen vähyys kertovat kuitenkin opettajien ottavan ohjelmoinnin opettamisen ennakkoluulotomasti käyttöönsä.Abstract. The main objective of this Master’s thesis is to explore Finnish primary school teachers’ readiness to teach programming and their attitudes towards teaching of programming. The new National Curriculum of Finland requires teachers to be able to teach programming commencing from autumn 2016. Koodiaapinen.fi has designed a massive open online course to educate Finnish teachers on teaching of programming to tackle this requirement. The research questionnaire was offered to the teachers who participated in the course. The results of this thesis are intended to be used on developing of the Finnish primary school teacher training on the area of teaching of programming. Research method of this thesis was web-based questionnaire (n=317). Instrument of the research is based on TAM (Technology Acceptance Model) (Davis, 1989.) and UTAUT (Unified Theory of Acceptance and Use of Technology) (Venkatesh et al., 2003.). Those models were translated and modified to match the research problem and the language of this thesis. One great contributor to the instrument was the questionnaire developed by the researchers of ”The programming studio: investigating teachers’ readiness for teaching programming in the Island of Ireland”. The questionnaire used in this thesis is partially similar to the one used in Ireland to allow direct comparison of the results between these studies. Main results of the thesis: About one in ten of the respondents declared to be able to teach some of the following programming languages: Scratch, Scratch Jr., Code.org and HTML/CSS. The respondents were significantly less familiar with other programming languages. However, almost half of the respondents indicated ability to solve problems of the teaching of programming even if there were no help available and over 70 % of the respondents declared they would solve those problems if they had enough time to work on the problem. Teaching of programming was seen necessary among the respondents as 74,1 % partially agreed or strongly agreed with the statement “the teaching of programming is needed in primary school”. The attitude towards teaching of programming is somewhat more positive than neutral among the respondents or the respondents were not yet able to state their attitudes. The general attitude and lack of anxiety among the respondents denotes that Finnish teachers are openmindedly welcoming programming into primary school’s curriculum

Production of a C-15 radioactive ion beam based on O-18(n, alpha)

.In the context of the SPIRAL2 radioactive beam facility the production rate of the neutron-rich C-15 nucleus by O-18(n,) has been investigated. In a water target of 20 cm(3), enriched in O-18 and placed behind the neutron converter, a rate of a few 10(10) nuclei per second can be reached with 1mA of 40MeV deuterons. A O-18(n,) cross-section based on the activation method is proposed. It is intermediate between the highest and lowest evaluations available to date.Peer reviewe

What influences the speed of prototyping? An empirical investigation of twenty software startups

It is essential for startups to quickly experiment business ideas by building tangible prototypes and collecting user feedback on them. As prototyping is an inevitable part of learning for early stage software startups, how fast startups can learn depends on how fast they can prototype. Despite of the importance, there is a lack of research about prototyping in software startups. In this study, we aimed at understanding what are factors influencing different types of prototyping activities. We conducted a multiple case study on twenty European software startups. The results are two folds, firstly we propose a prototype-centric learning model in early stage software startups. Secondly, we identify factors occur as barriers but also facilitators for prototyping in early stage software startups. The factors are grouped into (1) artifacts, (2) team competence, (3) collaboration, (4) customer and (5) process dimensions. To speed up a startups progress at the early stage, it is important to incorporate the learning objective into a well-defined collaborative approach of prototypingComment: This is the author's version of the work. Copyright owner's version can be accessed at doi.org/10.1007/978-3-319-57633-6_2, XP2017, Cologne, German

A sextupole ion beam guide to improve the efficiency and beam quality at IGISOL

The laser ion source project at the IGISOL facility, Jyvaskyla, has motivated the development and construction of an rf sextupole ion beam guide (SPIG) to replace the original skimmer electrode. The SPIG has been tested both off-line and on-line in proton-induced fission, light-ion and heavy-ion induced fusion-evaporation reactions and, in each case, has been directly compared to the skimmer system. For both fission and light-ion induced fusion, the SPIG has improved the mass-separated ion yields by a factor of typically 4 to 8. Correspondingly, the transmission efficiency of both systems has been studied in simulations with and without space charge effects. The transport capacity of the SPIG has been experimentally determined to be 10^12 ions/s before space charge effects start to take effect. A direct comparison with the simulation has been made using data obtained via light-ion fusion evaporation. Both experiment and simulation show an encouraging agreement as a function of current extracted from the ion guide.Comment: Latex formatted, submitted to NIM B, 17 pages with 22 .eps figure

The Laser Ion Source Trap (LIST) coupled to a gas cell catcher

The proof of principle of the Laser Ion Source Trap (LIST) coupled to a gas cell catcher system has been demonstrated at the Leuven Isotope Separator On-Line (LISOL). The experiments were carried out by using the modified gas cell-based laser ion source and the SextuPole Ion Guide (SPIG). Element selective resonance laser ionization of neutral atoms was taking place inside the cold jet expanding out of the gas cell catcher. The laser path was oriented in longitudinal as well as transverse geometries with respect to the atoms flow. The enhancement of beam purity and the feasibility for in-source laser spectroscopy were investigated in off-line and on-line conditions.Comment: 11 pages, 13 figure

Postexercise Heart Rate Recovery in Adults Born Preterm

Objective To evaluate postexercise heart rate recovery (HRR) in adults born preterm. Study design We studied the association between preterm birth and postexercise HRR in 545 adults (267 women) at 23.3 years of age (range 19.9-26.3 years). One hundred three participants were born early preterm ( Results Mean peak HR was 159.5 bpm in the early preterm (P = .16 with controls), 157.8 bpm in the late preterm (P = .56), and 157.0 bpm in the control group. Mean HRR 30 seconds after exercise was 3.2 bpm (95% CI 1.1-5.2) lower in the early preterm group and 2.1 bpm (0.3-3.8) lower in the late preterm group than the full term controls. Mean 60s HRR was 2.5 (-0.1 to 5.1) lower in the early preterm group and 2.8 bpm (0.6-4.9) lower in the late preterm group. Mean maximum slope after exercise was 0.10 beats/s (0.02-0.17) lower in the early preterm group and 0.06 beats/s (0.00-0.12) lower in the late preterm group. Conclusions Our results suggest reduced HRR after exercise in adults born preterm, including those born late preterm. This suggests altered reactivation of the parasympathetic nervous system, which may contribute to cardiovascular risk among adults born preterm.Peer reviewe

Early age exposure to moisture damage and systemic inflammation at the age of 6 years

Cross-sectional studies have shown that exposure to indoor moisture damage and mold may be associated with subclinical inflammation. Our aim was to determine whether early age exposure to moisture damage or mold is prospectively associated with subclinical systemic inflammation or with immune responsiveness in later childhood. Home inspections were performed in children's homes in the first year of life. At age 6 years, subclinical systemic inflammation was measured by serum C-reactive protein(CRP) and blood leucocytes and immune responsiveness by ex vivo production of interleukin 1-beta(IL-1beta), IL-6 and tumor necrosis factor-alpha(TNF-alpha) in whole blood cultures without stimulation or after 24h stimulation with phorbol 12-myristate 13-acetate and ionomycin(PI), lipopolysaccharide(LPS) or peptidoglycan(PPG) in 251 to 270 children. Moisture damage in child's main living areas in infancy was not significantly associated with elevated levels of CRP or leucocytes at 6 years. In contrast, there was some suggestion for an effect on immune responsiveness, as moisture damage with visible mold was positively associated with LPS-stimulated production of TNF-alpha and minor moisture damage was inversely associated with PI-stimulated IL-1beta. While early life exposure to mold damage may have some influence on later immune responsiveness, it does not seem to increase subclinical systemic inflammation in later life. This article is protected by copyright. All rights reserved