320 research outputs found

    SyömishÀiriöitÀ sairastaneiden tiedonhankinta virtuaalisista yhteisöistÀ

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    TiivistelmÀ. TÀmÀn pro gradu -tutkielman aiheena on syömishÀiriöitÀ sairastaneiden tiedonhankinta virtuaalisista yhteisöistÀ. Tutkielman tarkoituksena oli selvittÀÀ, millaisia virtuaaliset yhteisöt ovat tiedonlÀhteinÀ, millaisia informaatiokÀytÀnteitÀ ilmenee sekÀ millaista tieto ja tiedonhankinta on sairauden eri vaiheissa. LisÀksi tavoitteena oli selvittÀÀ, millaista vÀÀrÀÀ ja harhaanjohtavaa tietoa virtuaalisista yhteisöistÀ tunnistettiin sekÀ millaisia kokemuksia nousee esille laihdutuskulttuurista. Tutkielman aineisto kerÀttiin loka- ja marraskuussa 2018 ja kesÀllÀ 2019 teemahaastatteluilla. Tutkimukseni kohteena oli kaksitoista syömishÀiriöitÀ sairastanutta henkilöÀ, jotka olivat kÀyttÀneet virtuaalisia yhteisöjÀ tiedonhankintaan syömishÀiriöön liittyen. Tutkimusaineisto analysoitiin laadullisin menetelmin teoriaohjaavan sisÀllönanalyysin avulla. Tutkielman toteutuksessa noudatettiin tarkasti tutkimuksen eettisiÀ periaatteita. Tuloksissa korostui eritoten vertaistiedon ja -tuen suuri merkitys. Vertaistuen osalta ilmeni samoja tuloksia kuin aiemmissa tutkimuksissa (ks. muun muassa Eichhorn 2008). Vertaistietoa esiintyi neutraalin tiedon lisÀksi paranemista tukevana, haitallisena ja pro-anoreksia-ilmiöön liittyvÀnÀ tietona. TiedonhankintakÀytÀnteistÀ nousivat esille eritoten aktiivinen etsintÀ, aktiivinen seuranta ja informaatiosta pidÀttÀytyminen. Tietoa jaettiin vaihtelevasti kommenttien, julkaisujen ja viestien muodossa. Esiin tuli sairauden vaiheen yhteys tiedonhankintaan, minkÀ myötÀ myös kognitiiviset auktoriteetit saattoivat vaihdella. Kognitiivisiksi auktoriteeteiksi tunnistettiin vertaiset, lÀÀketieteelliset julkaisut, jÀrjestöjen asiantuntijat ja hoitotaho. VÀÀrÀÀ tietoa oli kohdattu useammin kuin harhaanjohtavaa tietoa. Misinformaatiota ilmeni epÀtarkkana ja heikosti sovellettavana informaationa, liioitteluna, vÀÀrinkÀsityksinÀ ja voimakkaasti sairauden sanelemina viesteinÀ. Haastatteluissa tuli esille laihdutuskulttuurin ilmeneminen tiedonhankinnan tuloksissa, ja tÀllainen laihduttamista korostava ja normalisoiva uutisointi, mainonta ja keskustelu koettiin haitallisina. Virtuaaliset yhteisöt vaikuttaisivat olevan merkittÀvÀ ja optimaalinen ympÀristö sekÀ vertaistuen ettÀ tiedon hankinnalle. Yhteisöjen haasteena on kuitenkin haitallisen tiedon mÀÀrÀ, mikÀ saattaa vaikeuttaa toipumista. HedelmÀllisiÀ jatkotutkimuksen aiheita olisikin, miten hyödyllisen ja tukevan vertaistiedon ja -tuen jakaminen onnistuisi parhaiten siten, ettÀ tiedosta tai tuesta ei olisi haittaa. LisÀksi kiinnostava jatkotutkimuksen aihe olisi, miten siirtyminen keskustelufoorumeilta sosiaaliseen median palveluihin on vaikuttanut tiedonhankintaan ja -jakamiseen

    Segregation, precipitation, and \alpha-\alpha' phase separation in Fe-Cr alloys: a multi-scale modelling approach

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    Segregation, precipitation, and phase separation in Fe-Cr systems is investigated. Monte Carlo simulations using semiempirical interatomic potential, first-principles total energy calculations, and experimental spectroscopy are used. In order to obtain a general picture of the relation of the atomic interactions and properties of Fe-Cr alloys in bulk, surface, and interface regions several complementary methods has to be used. Using Exact Muffin-Tin Orbitals method the effective chemical potential as a function of Cr content (0-15 at.% Cr) is calculated for a surface, second atomic layer and bulk. At ~10 at.% Cr in the alloy the reversal of the driving force of a Cr atom to occupy either bulk or surface sites is obtained. The Cr containing surfaces are expected when the Cr content exceeds ~10 at.%. The second atomic layer forms about 0.3 eV barrier for the migration of Cr atoms between bulk and surface atomic layer. To get information on Fe-Cr in larger scales we use semiempirical methods. Using combined Monte Carlo molecular dynamics simulations, based on semiempirical potential, the precipitation of Cr into isolated pockets in bulk Fe-Cr and the upper limit of the solubility of Cr into Fe layers in Fe/Cr layer system is studied. The theoretical predictions are tested using spectroscopic measurements. Hard X-ray photoelectron spectroscopy and Auger electron spectroscopy investigations were carried out to explore Cr segregation and precipitation in Fe/Cr double layer and Fe_0.95Cr_0.05 and Fe_0.85Cr_0.15 alloys. Initial oxidation of Fe-Cr was investigated experimentally at 10^-8 Torr pressure of the spectrometers showing intense Cr_2O_3 signal. Cr segregation and the formation of Cr rich precipitates were traced by analysing the experimental spectral intensities with respect to annealing time, Cr content, and kinetic energy of the exited electron.Comment: 16 pages, 14 figures, 52 reference

    Transfer learning for mobile robots

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    Abstract. In this project transfer learning can be defined as transferring previously learned knowledge to a new environment and making use of it to avoid obstacles. The feasibility of transfer learning was studied in a situation where a robot is given a task to navigate to a user-defined location in a virtual environment without hitting walls and utilizing reinforcement learning to teach the robot, which means that the robot will receive rewards according to the way it moves in the environment and how close it is to the goal location. In this project everything is done and tested in simulation. First the robot is trained in a standard environment, which is a simple hallway. It requires around 4000 iterations for the robot to learn better practices and reach the goal more frequently. When the training is done, the robot is moved to a test environment, which is otherwise similar to the standard one with the exception of a slanted floor, a ramp, in the beginning of the hallway. This proved to be an obstacle that the robot could not overcome without the help of sensor spoofing. Sensor spoofing in this case means inputting fake values to the robot’s laser sensor, which is responsible for detecting obstacles around the robot. The major target in this research was to transfer the previously learned data from the standard environment to the test environment and utilize sensor spoofing to help the robot overcome the slanted floor and eventually analyze if transfer learning helped the robot perform better. The performance can be compared by looking at the rewards received by the robot, since the robot receives highest rewards when reaching the goal location in the environment and negative rewards when crashing into walls. If transfer learning is beneficial for the robot, the robot should reach the goal point more frequently when making use of previously trained data from the standard environment and sensor spoofing in the test environment, compared to how it performs without them. This was also the result achieved. Even though the performance was not as good as it was without the ramp since without the ramp the robot reached the goal point every time after training around 200 episodes, the performance was better than it was without the trained model and sensor spoofing being used. As a result, transfer learning can be applied in virtual environments for mobile robots under certain restrictions. It can also be utilized in many other cases, this project is just one example. The codes and files used for this project are available on GitHub at https://github.com/lperala/Transfer_learning_for_mobile_robots.TiivistelmĂ€. TĂ€ssĂ€ projektissa oppimisen siirtĂ€minen voidaan mÀÀrittÀÀ aiemmin opitun tiedon siirtĂ€misenĂ€ uuteen ympĂ€ristöön ja sen hyödyntĂ€misenĂ€ esteiden vĂ€lttelyyn. Oppimisen siirtĂ€misen toteutettavuutta tutkittiin tilanteessa, jossa robotille on annettu tehtĂ€vĂ€ navigoida kĂ€yttĂ€jĂ€n mÀÀrittĂ€mÀÀn sijaintiin virtuaalisessa ympĂ€ristössĂ€ osumatta seiniin hyödyntĂ€en vahvistavaa oppimista robotin opettamiseksi, joka tarkoittaa ettĂ€ robotti saa positiivisia palkkioita sen mukaan miten se liikkuu ympĂ€ristössĂ€ ja kuinka lĂ€hellĂ€ se on tavoitesijaintia. TĂ€ssĂ€ projektissa kaikki on tehty ja testattu simulaatiossa. Ensin robotti koulutetaan standardiympĂ€ristössĂ€, joka on yksinkertainen kĂ€ytĂ€vĂ€. Robotti tarvitsee noin 4000 toistoa koulutusta, jotta se oppisi liikkumaan paremmin ja saavuttamaan tavoitesijaintinsa useammin. Kun koulutus on tehty, robotti siirretÀÀn testiympĂ€ristöön, joka on muuten samanlainen kuin standardiympĂ€ristö, mutta sisĂ€ltÀÀ kaltevan rampin kĂ€ytĂ€vĂ€n alussa. TĂ€mĂ€ osottautui esteeksi, jonka yli robotti ei kyennyt liikkumaan ilman sensorin huijaamista. Sensorin huijaaminen tarkoitti tĂ€ssĂ€ tapauksessa tekaistujen arvojen syöttĂ€mistĂ€ robotin lasersensorille, joka vastaa esteiden havaitsemisesta robotin ympĂ€rillĂ€. Suurin tavoite projektissa oli siirtÀÀ aiemmin opittu data standardiympĂ€ristöstĂ€ testiympĂ€ristöön ja hyödyntÀÀ sensorin huijaamista auttaakseen robottia ylittĂ€mÀÀn ramppi ja lopulta analysoida oliko oppimisen siirtĂ€misestĂ€ hyötyĂ€ robotin suoriutumisen kannalta. Suoriutumista voitiin tarkastella vertaamalla robotin kerÀÀmiĂ€ palkkioita, koska robotti saa isoimmat palkkionsa saavuttaessaan tavoitesijaintinsa ympĂ€ristössĂ€ ja taas negatiivisia palkkioita, mikĂ€li se törmÀÀ seinÀÀn. Jos oppimisen siirtĂ€minen on hyödyllistĂ€, se tarkottaisi ettĂ€ robotti saavuttaisi tavoitesijainnin useammin kun se hyödyntÀÀ aiemmin opittua dataa kuin jos se suoriutuisi ilman opittua dataa. TĂ€mĂ€ oli myös tulos johon pÀÀdyttiin. Vaikka suoriutuminen ei ollut yhtĂ€ hyvÀÀ kuin ilman ramppia, koska ilman ramppia robotti saavutti tavoitteensa jo 200 koulutusepisodin jĂ€lkeen, suoriutuminen oli parempaa kuin se oli tĂ€ysin ilman koulutusta ja sensorin huijaamista. Tuloksena, oppimisen siirtĂ€mistĂ€ voidaan hyödyntÀÀ virtuaalisissa ympĂ€ristöissĂ€ mobiileille roboteille tiettyjen rajoituksin. SitĂ€ voidaan myös hyödyntÀÀ monissa muissakin tapauksissa, tĂ€mĂ€ projekti on vain yksi esimerkki. Projektissa kĂ€ytetyt tiedostot ovat saatavilla GitHubissa osoitteesta https://github.com/lperala/Transfer_learning_for_mobile_robots

    Validation of the Finnish version of the SCOFF questionnaire among young adults aged 20 to 35 years

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    <p>Abstract</p> <p>Background</p> <p>We tested the validity of the SCOFF, a five-question screening instrument for eating disorders, in a general population sample.</p> <p>Methods</p> <p>A random sample of 1863 Finnish young adults was approached with a questionnaire that contained several screens for mental health interview, including the SCOFF. The questionnaire was returned by 1316 persons. All screen positives and a random sample of screen negatives were invited to SCID interview. Altogether 541 subjects participated in the SCID interview and had filled in the SCOFF questionnaire. We investigated the validity of the SCOFF in detecting current eating disorders by calculating sensitivity, specificity, and positive and negative predictive values (PPV and NPV) for different cut-off scores. We also performed a ROC analysis based on these 541 persons, of whom nine had current eating disorder.</p> <p>Results</p> <p>The threshold of two positive answers presented the best ability to detect eating disorders, with a sensitivity of 77.8%, a specificity of 87.6%, a PPV of 9.7%, and a NPV of 99.6%. None of the subjects with current eating disorder scored zero points in the SCOFF.</p> <p>Conclusion</p> <p>Due to its low PPV, there are limitations in using the SCOFF as a screening instrument in unselected population samples. However, it might be used for ruling out the possibility of eating disorders.</p

    ASIC-E4: Interplay of Beta-Amyloid, Synaptic Density and Neuroinflammation in Cognitively Normal Volunteers With Three Levels of Genetic Risk for Late-Onset Alzheimer's Disease – Study Protocol and Baseline Characteristics

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    Background: Detailed characterization of early pathophysiological changes in preclinical Alzheimer's disease (AD) is necessary to enable development of correctly targeted and timed disease-modifying treatments. ASIC-E4 study (“Beta-Amyloid, Synaptic loss, Inflammation and Cognition in healthy APOE Δ4 carriers”) combines state-of-the-art neuroimaging and fluid-based biomarker measurements to study the early interplay of three key pathological features of AD, i.e., beta-amyloid (AÎČ) deposition, neuroinflammation and synaptic dysfunction and loss in cognitively normal volunteers with three different levels of genetic (APOE-related) risk for late-onset AD. Objective: Here, our objective is to describe the study design, used protocols and baseline demographics of the ASIC-E4 study. Methods/Design: ASIC-E4 is a prospective observational multimodal imaging study performed in Turku PET Centre in collaboration with University of Gothenburg. Cognitively normal 60–75-year-old-individuals with known APOE Δ4/Δ4 genotype were recruited via local Auria Biobank (Turku, Finland). Recruitment of the project has been completed in July 2020 and 63 individuals were enrolled to three study groups (Group 1: APOE Δ4/Δ4, N = 19; Group 2: APOE Δ4/Δ3, N = 22; Group 3: APOE Δ3/Δ3, N = 22). At baseline, all participants will undergo positron emission tomography imaging with tracers targeted against AÎČ deposition (11C-PIB), activated glia (11C-PK11195) and synaptic vesicle glycoprotein 2A (11C-UCB-J), two brain magnetic resonance imaging scans, and extensive cognitive testing. In addition, blood samples are collected for various laboratory measurements and blood biomarker analysis and cerebrospinal fluid samples are collected from a subset of participants based on additional voluntary informed consent. To evaluate the predictive value of the early neuroimaging findings, neuropsychological evaluation and blood biomarker measurements will be repeated after a 4-year follow-up period. Discussion: Results of the ASIC-E4 project will bridge the gap related to limited knowledge of the synaptic and inflammatory changes and their association with each other and AÎČ in “at-risk” individuals. Thorough in vivo characterization of the biomarker profiles in this population will produce valuable information for diagnostic purposes and future drug development, where the field has already started to look beyond AÎČ

    PTFE Bypass or Thrupass for Superficial Femoral Artery Occlusion? A Randomised Controlled Trial

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    AbstractEarly results of a thrupass endograft in the treatment of femoral lesions are promising. Less morbidity and better cost-effectiveness are suggested to be achieved in the treatment of chronic lower limb ischaemia with endovascular treatment compared to surgical treatment.Patients and methodsThis randomised multicentre trial aimed to enroll a group of 60+60 patients for the treatment of 5–25-cm occlusions of superficial femoral artery (SFA) to be followed up for 3 years. Patients were treated either with endoluminal PTFE thrupass (WL Gore & Ass) or with surgical polytetrafluoroethylene (PTFE) bypass to proximal popliteal artery. Primary patency at 3 years was scheduled to be the primary end-point and secondary patency, functional success, costs and quality of life the secondary end-points.ResultsA sample of 100 consecutive SFA occlusions in one of the centres revealed that only 4% of the lesions were amenable for the study. The trial was prematurely terminated due to the results of an interim analysis at the time when 44 patients were recruited: the 1-year primary patency (excluding technical failures) was 48% for thrupass and 95% for bypass (p=0.02). The patency difference in favour of surgical bypass over endovascular thrupass was also sustained after completion of 1-year follow-up, the primary patencies being 46% and 84% at 1 year with grossly equilinear life-table curves thereafter (p=0.18), respectively. The corresponding secondary patencies were 63% and 100% (p=0.05) when excluding technical failures and 58% and 100% (p=0.02) according to intention-to-treat analysis. Secondary outcomes were thus not analysed.ConclusionTreatment of SFA occlusions (TASC IIB and C or Imelda Ia and II) should be done by PTFE bypass rather than by PTFE thrupass, as thrupass is connected with worse early outcome. These results represent only a small category of femoral disease

    Treatment adequacy of anxiety disorders among young adults in Finland

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