12 research outputs found
Hankintayksikkö terveen kilpailun vartijana – konsernisuhteen arvioiminen hankintalain 81 §:n 1 momentin 6 kohdan tarkoittamana kilpailua vääristävänä sopimuksena
Tutkielmassa selvitetään lainopillisen metodin avulla, miten samaan hankintamenettelyyn osallistuvien tarjoajien tai ehdokkaiden välinen konsernisuhde vaikuttaa hankintalain 81 §:n 1 momentin 6 kohdan tarkoittaman harkinnanvaraisen poissulkemisperusteen arviointiin. Tutkielmassa arvioidaan myös, millä edellytyksillä saman konsernin yritykset voivat osallistua keskenään samaan hankintamenettelyyn hankintalainsäädännön puitteissa.
Tutkielmassa tarkastellaan ensin yleisesti julkisissa hankinnoissa noudatettavia periaatteita ja hankintalain 81 §:n 1 momentin 6 kohdan soveltamisedellytyksiä. Tämän jälkeen arvioidaan konsernisuhdetta hankintalain 81 §:n 1 momentin 6 kohdan ja kilpailua vääristävän yhteistyön kontekstissa.
Tutkielman perusteella konsernisuhde luo olettaman siitä, että samaan hankintamenettelyyn osallistuneiden konserniyritysten tarjoukset eivät ole toisistaan riippumattomat. Hankintayksiköllä on tällöin velvollisuus selvittää, onko konsernisuhteella ollut konkreettista vaikutusta samaan hankintamenettelyyn osallistuneiden konserniyritysten tarjouksiin. Jos hankintayksikkö toteaa, että tarjoukset eivät ole toisistaan riippumattomat, sen on suljettava konserniyritykset pois hankintamenettelystä.
Tutkielman mukaan konserniyritysten tarjousten riippumattomuudesta vaadittavan näytön kynnystä ei voida tämänhetkisen oikeustilan perusteella määrittää. Tutkielman perusteella asiassa on tarvetta laajemmalle oikeustieteelliselle tutkimukselle, kansallisten ja EU-viranomaisten kannanotoille ja ohjeistuksille sekä erityisesti oikeustilaa täsmentävälle oikeuskäytännölle
The effectiveness of the coagulation sink of 3–10 nm atmospheric particles
As a major source of ultrafine particles, new particle formation (NPF) occurs frequently in various environments. However, the survival of new particles and the frequent occurrence of NPF events in polluted environments have long been perplexing, since new particles are expected to be scavenged by high coagulation sinks Towards solving these problems, we establish an experimental method and directly measure the effectiveness of the size-dependent coagulation sink of monodisperse 3-10 nm particles in well-controlled chamber experiments. Based on the chamber experiments and long-term atmospheric measurements from Beijing, we then discuss the survival of new particles in polluted environments. In the chamber experiments, the measured coagulation sink of 3-10 nm particles increases significantly with a decreasing particle size, whereas it is not sensitive to the compositions of test particles. Comparison between the measured coagulation coefficient with theoretical predictions shows that almost every coagulation leads to the scavenging of one particle, and the coagulation sink exceeds the hard-sphere kinetic limit due to van der Waals attractive force. For urban Beijing, the effectiveness of the coagulation sink and a moderate or high (e.g., > 3 nm h(-1)) growth rate of new particles can explain the occurrence of measured NPF events; the moderate growth rate further implies that, in addition to gaseous sulfuric acid, other gaseous precursors also contribute to the growth of new particles.Peer reviewe
Voimaharjoittelun ja harjoitustauon vaikutukset kortikospinaalisen radan toimintaan sekä maksimi- ja nopeusvoimaan harjoittelemattomilla aikuisilla
Tutkimuksessa tarkastelun kohteena oli kortikospinaalisen ärsytettävyyden ja inhibition muutokset voimaharjoittelun sekä sitä seuraavan harjoitustauon myötä sekä kortikospinaalisen radan toiminnan muutosten yhteydet maksimi- ja nopeusvoimassa tapahtuviin muutoksiin. Kortikospinaalinen rata vastaa lähes kaikesta motorisen toiminnan ohjauksesta ja kortikospinaalisen ärsytettävyyden parantumisen sekä inhibition vähentymisen on todettu olevan yhteydessä parantuneeseen voimantuottoon. Tutkimuksia kortikospinaalisen radan muutoksista voimaharjoittelun myötä on jonkin verran, mutta muutosten yhteyksiä maksimi- ja nopeusvoimaan on tutkittu vain vähän, etenkin harjoitustauon jälkeen. Tämän lisäksi harjoitustauon vaikutuksista nopeusvoimaan on hyvin vähän tutkimustietoa ja tutkimusten välillä on havaittavissa paljon ristiriitaisuutta. Näin ollen aiheiden tutkiminen on perusteltua.
Tutkimukseen osallistui harjoittelemattomia aikuisia (n=15), jotka toteuttivat seitsemän viikon harjoitusjakson ja viiden viikon harjoitustauon. Tutkittavien voimantuoton muutoksia mitattiin maksimaalisella tahdonalaisella supistuksella (MVC) sekä voimantuottonopeudella (RFD 50 ms, 75 ms ja 100 ms ajalta). Kortikospinaalisen radan toiminnan muutoksia mitattiin rectus femoris lihaksesta maksimaalisella M-aallolla (Mmax) sekä transkraniaalisella magneettistimulaatiolla aikaansaatavilla motorisella herätevasteella (MEP) sekä ”hiljaisella jaksolla” (SP). Mittaukset suoritettiin ennen ja jälkeen harjoitusjakson sekä harjoitustauon jälkeen.
Voimaharjoittelun myötä RFD 50 ms ajalta heikkeni (p<0,05), mutta MVC:ssä tai kortikospinaalisen radan toiminnassa ei ollut havaittavissa merkitseviä muutoksia. Kortikospinaalisen inhibition vähentymisen ja RFD:n heikentymisen välillä oli kuitenkin havaittavissa positiivisia korrelaatioita. Voimantuotossa tai kortikospinaalisen radan toiminnassa ei ollut havaittavissa merkitseviä muutoksia harjoitustauon jälkeen, mutta yksilötasolla kortikospinaalisen ärsytettävyyden laskun ja MVC:n laskun välillä oli havaittavissa positiivinen korrelaatio.
Voimaharjoittelulla ei siis ollut vaikutusta maksimivoimaan tai kortikospinaaliseen radan toimintaan. Voimaharjoittelun havaittiin kuitenkin vaikuttavan heikentävästi RFD:n alkuosaan, minkä lisäksi kortikospinaalisen inhibition laskun todettiin olevan yhteydessä RFD:n heikentymiseen yksilötasolla. Muutosten vähäisyys selittyy todennäköisesti riittämättömällä voimaharjoittelulla ja/tai itse mittausmenetelmillä, jotka eivät olleet tarpeeksi sensitiivisiä havaitsemaan muutoksia eivätkä voimantuoton kohdalla vastanneet tarpeeksi hyvin harjoittelussa käytettyä lihastyötapaa tai nivelkulmia. Harjoitustauolla ei myöskään havaittu olevan vaikutusta maksimi- tai nopeusvoimaan, eikä kortikospinaalisen radan toimintaan. Harjoitustauon myötä ilmenneissä muutoksissa havaittiin kuitenkin yksilötasolla yhteys kortikospinaalisen ärsytettävyyden laskun ja maksimivoiman laskun välillä. Kyseinen tulos on merkittävä, sillä aihetta on tutkittu aiemmin vain vähän ja havainto osoittaa, että kortikospinaalisen radan toiminnan muutoksilla on mahdollisesti vaikutusta harjoitustauon myötä maksimivoimassa ilmeneviin muutoksiin. Tutkimuksia voimaharjoittelun ja etenkin harjoitustauon vaikutuksista kortikospinaaliseen rataan ja sen yhteyksistä voimantuottoon tarvitaan kuitenkin lisää, sillä tutkimus tuloksissa on havaittavissa suuria vaihteluita, kuten tämäkin tutkimus osoittaa. Tutkimusta olisi hyvä tehdä suuremmalla otoskoolla, sekä jakamalla naiset ja miehet erillisiin ryhmiin, jotta myös sukupuolten välisiä eroja voitaisiin tarkastella.The purpose of this study was to examine the changes in corticospinal excitability and inhibition after strength training and detraining. The study also examined the associations between the changes in corticospinal tract and maximal strength and power. The corticospinal pathway is responsible for almost all the control of motor function and improvements in corticospinal excitability and reductions in inhibition have been found to be associated with improved force output. Thus, while there has been some research on changes in the corticospinal tract after strength training, relatively little research has been done on the associations between those changes and changes in maximal strength and power. In addition, the amount of research on the changes and associations after detraining is even lower and some inconsistency between studies can be seen. Therefore, further research on this subject is needed.
The study involved untrained adults (n=15) who completed a 7-week training period and a 5-week detraining period. The changes in subjects' maximal strength were measured with maximal voluntary contraction (MVC) and rate of force development (RFD between 0–50 ms, 0–75 ms and 0–100 ms). Changes in the corticospinal tract were measured from rectus femoris with maximal M-wave (Mmax) and with motor evoked potential (MEP) and silent period (SP) which were induced by transcranial magnetic stimulation. Measurements were performed before and after the training period and after the detraining.
RFD between 0–50 ms decreased after strength training, but no significant changes were observed in MVC or in the corticospinal excitability or inhibition. However, positive correlations were observed at the individual level between the reduction in corticospinal inhibition and RFD. No significant changes in maximal strength, power or corticospinal excitability or inhibition were observed after the detraining, but a positive correlation was observed at the individual level between the decrease in corticospinal excitability and in MVC.
Strength training had no effect on maximal strength or corticospinal excitability or inhibition. However, strength training caused a decrease in the initial part of the RFD. In addition, decrease in corticospinal inhibition was found to be associated with the decrease in RFD at the individual level. The lack of changes in other parameters is likely to be explained by insufficient strength training and/or the measurement methods used, which were not sensitive enough to detect changes. The muscle contraction type and joint angles used in strength training and in the MVC- and RFD-measurements probably also differed too much and thus no changes could be seen in the parameters in question. In addition, detraining was found to have no significant effect on maximal strength or power, nor on corticospinal excitability or inhibition. However, an association was found between the decrease in corticospinal excitability and the decrease in maximal strength at the individual level. This result is significant since little research has been done on the topic and the finding indicates that changes in corticospinal tract may have an influence on the changes in maximal force during detraining. Nevertheless, more research on the effects of strength training and detraining on the corticospinal tract and especially its association to power is needed. As this study also shows, there is a lot of variability in the results of studies. It would be recommended to conduct the study with a larger sample size, and to divide women and men into separate groups, so that gender differences could also be examined
Increasing the material management platform usage rate
The purpose of this thesis was to find ways to increase the customer usage rate of an advertisement material platform, commissioned by Sanoma Media Finland. The goal was to identify the issues with the platform usage and to create a development plan for the company.
The theoretical framework consists of behavioral themes, such as change leadership and behavioral economics, as well as more technically oriented themes, such as customer onboarding and user interface experience and design.
The method used for gathering information was gathered from literature sources as well as company policy documentations. The main method for information gathering for the development phase was semi-structured interviews of internal stakeholders.
The key finding was that while there are many practical steps that can be taken to help increase the usage rate of the platform, the most pressing issues are foundational. Internal confusion can lead to an inconsistent customer experience. Based on the findings and the theoretical framework, there are suggestions for moving forward with getting more customers to use the platform independently
Thermally induced evaporation of organic aerosol from alpha-pinene ozonolysis
Atmospheric aerosol particles affect Earth’s radiation balance, human health and visibility. Secondary organic aerosol (SOA) contributes a significant fraction to the total atmospheric organic aerosol, and thus plays an important role in climate change. SOA is formed through oxidation of volatile organic compounds (VOCs) and it consists of many individual organic compounds with varying properties. The oxidation products of VOCs include highly oxygenated organic molecules (HOM) that are estimated to explain a large fraction of SOA formation. To estimate the climate impacts of SOA it is essential to understand its properties in the atmosphere.
In this thesis, a method to investigate thermally induced evaporation of organic aerosol was developed. SOA particles were generated in a flow tube from alpha-pinene ozonolysis and then directed into a heated tube to initiate particle evaporation. The size distribution of the particles was measured with
parallel identification of the evaporated HOM. This method was capable of providing information of SOA evaporation behaviour and the particle-phase composition at different temperatures.
Mass spectra of the evaporated HOM and particle size distribution data were analyzed. The obtained results suggest that SOA contains compounds with a wide range of volatilities, including HOM monomers, dimers and trimers. The volatility behaviour of the particulate HOM and their contribution to SOA particle mass was studied. Furthermore, indications of particle-phase reactions occurring in SOA were found
Aerosolimittalaitteiden kalibrointimenetelmän kehitys
Opinnäytetyö suoritettiin ilmakehätieteiden osastolla Helsingin yliopiston fysiikan laitoksella.
Opinnäytetyön tavoitteena oli kehittää aerosolimittalaitteiden kalibrointiin soveltuva laitteisto, joka tuottaa kerran varattuja, ominaisuuksiltaan hyvin määriteltyjä hiukkasia. Hiukkasten tulee olla kerran varattuja, sillä monesti varautuneet hiukkaset aiheuttavat ongelmia aerosolihiukkasten koko- ja lukumääräpitoisuuskalibroinnissa. Laitteiston kehityksessä otettiin mallia Jaakko Yli-Ojanperän kehittämästä SCAR (Single Charged Aerosol Reference) -laitteistosta, joka on validoitu 10 – 500 nm kokoisten hiukkasten lukumääräpitoisuusstandardiksi.
Kalibrointilaitteisto rakennettiin, sen toiminta varmistettiin, ja sille määritettiin optimaaliset mittausolosuhteet. Laitteiston testaus suoritettiin kalibroimalla hiukkasten kokoa mittaava differentiaalinen liikkuvuusanalysaattori ja hiukkasten lukumääräpitoisuutta mittaava kondensaatiohiukkaslaskuri.
Työssä onnistuttiin kehittämään aerosolimittalaitteille kalibrointilaitteisto, joka tuottaa kapeita, yhdesti varautuneiden hiukkasten kokojakaumia 1 µm hiukkaskokoon asti. Kahdesti varautuneiden hiukkasten osuus on vain 0,043 %, eli lähes yhtä pieni kuin SCAR-laitteistossa. Kehitettyä laitteistoa voidaan käyttää hiukkasten lukumääräpitoisuusstandardina hiukkaskokoalueella 12 – 1000 nm pitoisuuteen 20 000 cm-3 asti ja sillä voidaan kalibroida luotettavasti aerosolimittalaitteita.This study was carried out at the Division of Atmospheric Sciences in the Department of Physics, University of Helsinki.
The aim of the study was to develop a calibration device for aerosol measurement instruments that generates singly charged aerosol particles with a narrow size distribution. The particles should be singly charged, because multiply charged particles cause error in the size and number concentration calibrations. The built calibration device is similar as the SCAR (Single Charged Aerosol Reference) –device, which Jaakko Yli-Ojanperä has designed.
The calibration device was built, its performance was assessed and the optimum measurement conditions were determined. The device was tested by calibrating differential mobility analyser and condensation particle counter.
In this study a calibration device that generates narrow size distribution of singly charged particles up to 1 µm size was developed. The fraction of the doubly charged particles is only 0.043 %, which is almost as small as in the SCAR –device. The device can be used as a particle number concentration standard for reliable calibration of aerosol measurement instruments. The calibration can be done in the particle size range of 12 – 1000 nm until the concentration reaches 20 000 cm-3
Noviisiluokanopettajan työn tukeminen toiveita uran alun tukemisesta sekä kokemuksia mentoroinnista
Test-retest reliability of motor-evoked potentials at 20% and 60% of maximum isometric voluntary contraction in rectus femoris muscle
nonPeerReviewe
Test–retest reliability of cortico-spinal measurements in the rectus femoris at different contraction levels
Single-pulse Transcranial Magnetic Stimulation (TMS) and, very recently, lumbar stimulation (LS) have been used to measure cortico-spinal excitability from various interventions using maximal or submaximal contractions in the lower limbs. However, reliability studies have overlooked a wide range of contraction intensities for MEPs, and no reliability data is available for LEPs. This study investigated the reliability of motor evoked potentials and lumbar evoked potentials at different stimulation intensities and contraction levels in m.rectus femoris. Twenty-two participants performed non-fatiguing isometric knee extensions at 20 and 60% of maximum voluntary contraction (MVC). LS induced a lumbar-evoked potential (LEP) of 25 and 50% resting maximal compound action potential (M-max). TMS stimulator output was adjusted to 120, 140, and 160% of active motor threshold (aMT). In each contraction, a single MEP or LEP was delivered. Ten contractions were performed at each stimulator intensity and contraction level in random order. Moderate-to-good reliability was found when LEP was normalized to M-max/ Root Mean Square in all conditions (ICC:0.74–0.85). Excellent reliability was found when MEP was normalized to Mmax for all conditions (ICC > 0.90) at 60% of MVC. Good reliability was found for the rest of the TMS conditions. Moderateto-good reliability was found for silent period (SP) elicited by LS (ICC: 0.71–0.83). Good-to-excellent reliability was found for SP elicited by TMS (ICC > 0.82). MEPs and LEPs elicited in m.rectus femoris appear to be reliable to assess changes at different segments of the cortico-spinal tract during different contraction levels and stimulator output intensities. Furthermore, the TMS- and LS- elicited SP was a reliable tool considered to reflect inhibitory processes at spinal and cortical levels.peerReviewe
Online measurement of highly oxygenated compounds from organic aerosol
Highly oxygenated compounds are important contributors to the formation and growth of atmospheric organic aerosol and thus have an impact on Earth's radiation balance and global climate. However, knowledge of the contribution of highly oxygenated compounds to organic aerosol and their fate after condensing into the particle phase has been limited by the lack of suitable detection techniques. Here, we present a new online method for measuring highly oxygenated compounds from organic aerosol. The method includes thermal evaporation of particles in a new inlet, the vaporization inlet for aerosols (VIA), followed by identification of the evaporated highly oxygenated compounds by a nitrate chemical ionization mass spectrometer (NO3-CIMS). The method does not require sample collection, enabling highly time-resolved measurements of particulate compounds. We evaluate the performance of the method by measuring the detection limit and performing background measurements. We estimate a detection limit of below 1 ng m(-3) for a single compound and below 1 mu g m(-3) for SOA with the sampling setup used here. These detection limits can be improved upon by optimizing the flow setup. Furthermore, we detect hundreds of particulate highly oxygenated compounds from organic aerosol generated from different precursors. Our results are consistent with previous studies showing that the volatility of organic compounds decreases with increasing m/z ratio and level of oxygenation and that organic aerosol consists of monomers and oligomeric compounds. By comparing the gas- and particle-phase compounds, we found indications of potential particle-phase reactions occurring in organic aerosol. Future work will focus both on further improving the sampling design and on better understanding the evaporation dynamics of the system, but already these initial tests show that the VIA coupled to the NO3-CIMS is a promising method for investigating the transformations and fate of the compounds after condensing into the particle phase.Peer reviewe