Exploring behaviour patterns with self-organizing map for personalised mental stress detection

Abstract. Stress is an important health problem and the cause for many illnesses and working days lost. It is often measured with different questionnaires that capture only the current stress levels and may come in too late for early prevention. They are also prone to subjective inaccuracies since the feeling of stress, and the physiological response to it, have been found to be individual. Real-time stress detectors, trained on biosignals like heart rate variability, exist but majority of them employ supervised learning which requires collecting a large amount of labelled data from each system user. Commonly, they are tested in situations where the stress response is deliberately induced (e.g. laboratory). Thus they may not generalise to real-life conditions where more general behavioural data could be used. In this study the issues with labelling and individuality are addressed by fitting unsupervised stress detection models at several personalisation levels. The method explored, the Self-Organizing Map, is combined with different clustering algorithms to find personal, semi-personal and general behaviour patterns that are converted to stress predictions. Laboratory biosignal-data are used for method validation. To provide an always-on type stress detection, real-life behavioural data consisting of biosignals and smartphone data are experimented on. The results show that personalisation does improve the predictions. The best classification performance for the laboratory data was found with the fully personalised model (F1-score 0.89 vs. 0.45 with the general model) but for the real-life data there was no big difference between fully personal (F1-score 0.57) and general model as long as the behaviour patterns were mapped to stress individually (F1-score 0.60). While the scores also validate the feasibility of SOM for mental stress detection, further research is needed to determine the most suitable and practical level of personalisation and an unambiguous mapping between behaviour patterns and stress.Tiivistelmä. Stressi on merkittävä terveysongelma ja syynä useisiin sairauksiin sekä työpoissaoloihin. Sitä mitataan usein erilaisilla kyselyillä, jotka kuvaavat vain hetkellistä stressitasoa ja joihin voidaan vastata liian myöhään ennaltaehkäisyn kannalta. Kyselyt ovat myös alttiita subjektiivisille epätarkkuuksille, koska stressintunteen, ja stressinaikaisten fysiologisten reaktioiden, on havaittu olevan yksilöllisiä. Reaaliaikaisia, biosignaalien kuten sykevälivaihtelun analyysiin perustuvia, stressintunnistimia on olemassa, mutta pääosin ne käyttävät ohjatun oppimisen menetelmiä, mikä vaatii jokaiselta järjestelmän käyttäjältä suuren stressintunteella merkityn aineiston. Stressintunnistimia myös usein testataan tilanteissa, joissa stressi on tahallisesti aiheutettua (esimerkiksi laboratoriossa). Siten ne eivät yleisty tosielämän tarpeisiin, jolloin voidaan käyttää yleisempää käyttäytymistä kuvaavaa aineistoa. Tässä tutkimuksessa vastataan datan merkintäongelmaan sekä yksilöllisyyden huomioimiseen käyttäen ohjaamattoman oppimisen stressintunnistusmalleja eri yksilöimisen tasoilla. Käytetty menetelmä, itseorganisoituva kartta, yhdistetään eri ryhmittelyalgoritmeihin tavoitteena löytää henkilökohtaiset, osin henkilökohtaiset sekä yleiset käyttäytymismallit, jotka muunnetaan stressiennusteiksi. Menetelmän sopivuuden vahvistamiseksi käytetään laboratoriossa kerättyä biosignaalidataa. Menetelmää sovelletaan myös tosielämän stressintunnistukseen biosignaaleista ja älypuhelimen käyttödatasta koostuvalla käyttäytymisaineistolla. Tulokset osoittavat, että yksilöiminen parantaa ennustetarkkuutta. Laboratorio-aineistolla paras luokittelutarkkuus löydettiin täysin yksilöllisellä mallilla (F1-pistemäärä 0.89, kun yleisellä 0.45). Tosielämän aineistolla täysin yksilöllisen (F1-pistemäärä 0.57) ja yleisen mallin, jossa käyttäytymismallien ja stressin välinen kuvaus määrättiin yksilöidysti (F1-pistemäärä 0.60), välinen ero ei ollut suuri. Vaikka tulokset vahvistavatkin itseorganisoituvan kartan sopivuuden psyykkisen stressin tunnistamisessa, lisätutkimusta tarvitaan määräämään soveltuvin ja käytännöllisin yksilöimisen taso sekä yksikäsitteinen kuvaus käyttäytymismallien ja stressin välille

Adherence to prescribing restrictions for HER2-positive metastatic breast cancer in Australia: A national population-based observational study (2001-2016)

Background: Targeted cancer therapy is often complex, involving multiple agents and chemotherapeutic partners. In Australia, prescribing restrictions are put in place to reflect existing evidence of cost-effectiveness of these medicines. As therapeutic options continue to expand, these restrictions may not be perceived to align with best practice and it is not known if their use in the real-world clinic adheres to these restrictions. We examined the treatment of women receiving trastuzumab for HER2-positive metastatic breast cancer (HER2+MBC) to determine the extent to which treatment adhered to national prescribing restrictions. Patients and methods: Our population-based, retrospective cohort study used dispensing records for every Australian woman initiating publicly-subsidised trastuzumab for HER2+MBC between 2001±2013, followed through 2016. We used group-based trajectory models (GBTMs) to cluster patients, first on their patterns of trastuzumab exposure, and then on their patterns of lapatinib and chemotherapy exposure. We described the characteristics of patients within each cluster, and examined their treatments and combinations of treatments to determine restriction adherence. Results: Of 5,052 patients initiating trastuzumab, 1,795 (36%) received at least one non-adherent HER2-targeted treatment. The most common non-adherent treatments were trastuzumab combinations involving vinorelbine (24% of non-adherent treatments); capecitabine (24%); and anthracyclines (10%). Non-adherent lapatinib use was observed in 4% of patients. GBTM identified three trastuzumab exposure clusters, each containing three further subclusters. The largest proportions of non-adherent treatments were in sub-clusters with longer trastuzumab exposure and more non-taxane chemotherapy. Patients in these sub-clusters were younger than those in sub-clusters with less non-adherent treatment. Conclusions: Our study highlights that, even during the relatively simpler treatment era of our study period, a substantial amount of treatment did not adhere to prescribing restrictions. As more trials are conducted exploring pertuzumab and T-DM1 in combination with different chemotherapies and other HER2-targeted therapies, the regulation and funding of HER2-targeted treatment will become more challenging

FEM-laskennan hyödyntäminen puisen tilaelementtikerrostalon stabiliteetin laskennassa

Tiivistelmä. Työn tarkoituksena ja tavoitteena on tarkastella 8-kerroksisen puisen tilaelementtikerrostalon rakenteellista toimivuutta sekä jäykistysmitoitusta FEM-laskentaa käyttäen. Työssä on lähdetty etsimään ratkaisua ongelmaan, että onko mahdollista rakentaa korkeaa puurankarunkoista kerrostaloa Lehto Group Oyj:n puutilaelementeillä, jossa jäykistävinä rakenteina toimivat kipsilevyt. Tutkimusmenetelmänä työssä on käytetty FEM-laskentaa ja ohjelmistona Strusoftin FEM-design -laskentaohjelmistoa. Lähtötiedot, jotka FEM-ohjelmaan syötetään, on laskettu Eurokoodin mitoitusperusteiden mukaisesti. FEM-laskentamallin tuloksia tarkastellaan muun muassa Finnwood -laskentaohjelman avulla. Työssä suurimmaksi sallituksi vaakasiirtymäksi on määritetty H/300, jonka täytyy toteutua käyttörajatilamitoituksessa. FEM-laskentamallin analysoinnin perusteella maksimivaakasiirtymä rakennuksessa ei ylity sallittua arvoa. Murtorajatilassa tilaelementin seinärakenteisiin syntyvät puristavat viivakuormat kasvavat hallitsemattoman suuriksi. Myös nurkkapilareihin kohdistuvat puristuskuormat ylittävä liimapuupilarin kapasiteetin. Vetopuolen kuormat pysyvät puolestaan maltillisina

Ristikkorakenteet ja niiden analysointi eri menetelmillä

Tiivistelmä. Tämän kandidaatintyön aiheena on ristikkorakenteen analysointi ja tarkastelu. Työssä käytetään analyyttista menetelmää, graafista menetelmää sekä tietokoneohjelmaa ristikon sauvavoimien määrittämiseksi. Sauvavoimat lasketaan siis kolmella eri tavalla, ja jokaisessa menetelmässä käytetään samaa ristikkorakennetta. Eri menetelmillä saatuja tuloksia verrataan keskenään. Työssä käytettään kirjallista tutkimusta teoriaosioissa ja kokeellista tutkimusta laskuesimerkkiä tarkasteltaessa. Analyyttisella menetelmällä ja graafisella menetelmällä laskiessa käytetään piirtotyökaluna Autodeskin AutoCad-ohjelmaa. Tietokoneohjelmana sauvavoimien laskemiseksi käytetään Autodeskin Robot Structural Analysis Professional -ohjelmaa. Ristikon sauvavoimien määrittäminen kullakin menetelmällä toivat samat tulokset, joka oli työn tavoitteenakin. Tulosten yhtäsuuruus todistaa, että ilman sen suurempia apuvälineitä on mahdollista päästä oikeisiin tuloksiin.Truss systems and their analysis by different methods. Abstract. The subject of this bachelor’s thesis is analysis and review of the truss system. In this thesis there is used analytical and graphical method and also the computer program to determine member axial forces of the truss system. The results are compared with each other. In this thesis literary research and empirical research is used. Autodesk AutoCad and Robot Structural Analysis Professional programs are used by graphical and calculatory tools. The results of the axial forces are the same by every method which was the target of this research. Because the results are same by every method it is not necessary to use lots of aids to get the right results

Multitaxa species richness of a wood-pasture complex in the Finnish SW-archipelago

Traditional rural biotopes such as semi-natural grasslands and wood-pastures are among the most threatened biotopes in Finland. Archipelago Sea area hosts an especially representative collection of these biotopes, considering both their combined area and average quality. We surveyed birds, vascular plants, bryophytes, polypores and ground-inhabiting stipitate macrofungi in one wood-pasture complex in Korppoo, Archipelago Sea area. Here we report and discuss the results of these surveys. We detected altogether 457 species, including 8 red-listed bird species and 6 red-listed vascular plant species. We didn´t detect any red-listed bryophytes or fungi, but also these groups included several rare or indicator species as well as some fungal species not included in the latest Finnish red-list evaluation. The conservation value of this wood-pasture complex constitutes of species that are dependent on highly variable set of ecological conditions and habitats. This is related to highly variable conditions typical to wood pastures as a habitat

Maintenance inhaler therapy preferences of patients with asthma or chronic obstructive pulmonary disease:a discrete choice experiment

Background A variety of maintenance inhaler therapies are available to treat asthma and COPD. Patient-centric treatment choices require understanding patient preferences for the alternative therapies. Methods A self-completed web-based discrete choice experiment was conducted to elicit patient preferences for inhaler device and medication attributes. Selection of attributes was informed by patient focus groups and literature review. Results The discrete choice experiment was completed by 810 patients with asthma and 1147 patients with COPD. Patients with asthma most valued decreasing the onset of action from 30 to 5 min, followed by reducing yearly exacerbations from 3 to 1. Patients with COPD most and equally valued decreasing the onset of action from 30 to 5 min and reducing yearly exacerbations from 3 to 1. Both patients with asthma and patients with COPD were willing to accept an additional exacerbation in exchange for a 15 min decrease in onset of action and a longer onset of action in exchange for a lower risk of adverse effects from inhaled corticosteroids. Patients with asthma and COPD valued once-daily over twice-daily dosing, pressurised inhalers over dry powder inhalers and non-capsule priming over single-use capsules, although these attributes were not valued as highly as faster onset of action or reduced exacerbations. Conclusions The most important maintenance inhaler attributes for patients with asthma and COPD were fast onset of symptom relief and a lower rate of exacerbations. Concerns about safety of inhaled corticosteroids and device convenience also affected patient preferences but were less important

Dual-combination maintenance inhaler preferences in asthma and chronic obstructive pulmonary disease:A patient-centered benefit-risk assessment

Background: A variety of dual-combination maintenance inhalers are used to treat asthma and chronic obstructive pulmonary disease (COPD). Understanding patient preferences for treatment attributes may help select an optimal treatment from the patient perspective. Methods: Patient preferences for maintenance inhaler device and medication attributes were elicited through a discrete choice experiment and used in benefit-risk assessments to calculate predicted choice probabilities (PrCPs) for 14 dual-combination maintenance inhalers in four treatment classes: lower- and higher-dose inhaled corticosteroid (ICS)/long-acting beta agonist (LABA) inhalers for asthma, and ICS/LABA and long-acting muscarinic antagonist (LAMA)/LABA inhalers for COPD. Results: For all treatment classes, reduced exacerbations and faster onset of action were the most important attributes. For all classes, patients were willing to tolerate an extra yearly exacerbation to decrease the medication's onset of action from 30 to 5 min. For patients with asthma using lower-dose ICS/LABA (n = 497), budesonide/formoteml fumarate dihydrate (80 mu g/4.5 mu g) pressurized metered-dose inhaler (pMDI) had the highest PrCP (28.4%), and for those using a higher-dose ICS/LABA (n = 285), PrCPs were highest for mometasone furoate/formoterol fumarate dihydrate (200 mu g/5 mu g) pMDI (27.0%) and budesonide/formoterol fumarate dihydrate (160 mu g/4.5 mu g) pMDI (26.9%). For patients with COPD using an ICS/LABA (n = 574), budesonide/ formoterol fumarate dihydrate (160 mu g/4.5 mu g) pMDI had the highest PrCP (56.6%), and for those using a LAMA/LABA inhaler (n = 217), tiotropium/olodaterol (2.5 mu g/2.5 mu g) soft mist inhaler had the highest PrCP (42.3%). Conclusions: Patient preference data for maintenance inhaler attributes can be used to identify a preference order of inhalers in different treatment classes

Mapping Transient Hyperventilation Induced Alterations with Estimates of the Multi-Scale Dynamics of BOLD Signal

Temporal blood oxygen level dependent (BOLD) contrast signals in functional MRI during rest may be characterized by power spectral distribution (PSD) trends of the form 1/fα. Trends with 1/f characteristics comprise fractal properties with repeating oscillation patterns in multiple time scales. Estimates of the fractal properties enable the quantification of phenomena that may otherwise be difficult to measure, such as transient, non-linear changes. In this study it was hypothesized that the fractal metrics of 1/f BOLD signal trends can map changes related to dynamic, multi-scale alterations in cerebral blood flow (CBF) after a transient hyperventilation challenge. Twenty-three normal adults were imaged in a resting-state before and after hyperventilation. Different variables (1/f trend constant α, fractal dimension Df, and, Hurst exponent H) characterizing the trends were measured from BOLD signals. The results show that fractal metrics of the BOLD signal follow the fractional Gaussian noise model, even during the dynamic CBF change that follows hyperventilation. The most dominant effect on the fractal metrics was detected in grey matter, in line with previous hyperventilation vaso-reactivity studies. The α was able to differentiate also blood vessels from grey matter changes. Df was most sensitive to grey matter. H correlated with default mode network areas before hyperventilation but this pattern vanished after hyperventilation due to a global increase in H. In the future, resting-state fMRI combined with fractal metrics of the BOLD signal may be used for analyzing multi-scale alterations of cerebral blood flow

Effect of atomic layer deposition on the quality factor of silicon nanobeam cavities

In this work we study the effect of thin-film deposition on the quality factor (Q) of silicon nanobeam cavities. We observe an average increase in the Q of 38±31% in one sample and investigate the dependence of this increase on the initial nanobeam hole sizes. We note that this process can be used to modify cavities that have larger than optimal hole sizes following fabrication. Additionally, the technique allows the tuning of the cavity mode wavelength and the incorporation of new materials, without significantly degrading Q

The use of MCDA in HTA : great potential, but more effort needed

The potential for multi-criteria decision analysis (MCDA) to support health technology assessment (HTA) has been much discussed, and various HTA agencies are piloting or applying MCDA. Alongside these developments, good practice guidelines for the application of MCDA in health care have been developed. An assessment of current applications of MCDA to HTA in light of good practice guidelines reveals, however, that many have methodologic flaws that undermine their usefulness. Three challenges are considered: the use of additive models, a lack of connection between criteria scales and weights, and the use of MCDA in economic evaluation. More attention needs to be paid to MCDA good practice by researchers, journal editors, and decision makers and further methodologic developments are required if MCDA is to achieve its potential to support HTA