139585 research outputs found
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Multimodal Digital Phenotyping Study in Patients With Major Depressive Episodes and Healthy Controls (Mobile Monitoring of Mood): Observational Longitudinal Study
No full textBackground: Mood disorders are among the most common mental health conditions worldwide. Wearables and consumer-grade personal digital devices create digital traces that can be collected, processed, and analyzed, offering a unique opportunity to quantify and monitor individuals with mental disorders in their natural living environments. Objective: This study comprised (1) 3 subcohorts of patients with a major depressive episode, either with major depressive disorder, bipolar disorder, or concurrent borderline personality disorder, and (2) a healthy control group. We investigated whether differences in behavioral patterns could be observed at the group level, that is, patients versus healthy controls. We studied the volume and temporal patterns of smartphone screen and app use, communication, sleep, mobility, and physical activity. We investigated whether patients or controls exhibited more homogenous temporal patterns of activity when compared with other individuals in the same group. We examined which variables were associated with the severity of depression. Methods: In total, 188 participants were recruited to complete a 2-phase study. In the first 2 weeks, data from bed sensors, actigraphy, smartphones, and 5 sets of daily questions were collected. In the second phase, which lasted up to 1 year, only passive smartphone data and biweekly 9-item Patient Health Questionnaire data were collected. Survival analysis, statistical tests, and linear mixed models were performed. Results: Survival analysis showed no statistically significant difference in adherence. Most participants did not stay in the study for 1 year. Weekday location variance showed lower values for patients (control: mean –10.04, SD 2.73; patient: mean –11.91, SD 2.50; Mann-Whitney U [MWU] test P=.004). Normalized entropy of location was lower among patients (control: mean 2.10, SD 1.38; patient: mean 1.57, SD 1.10; MWU test P=.05). The temporal communication patterns of controls were more diverse compared to those of patients (MWU test P<.001). In contrast, patients exhibited more varied temporal patterns of smartphone use compared to the controls. We found that the duration of incoming calls (β=–0.08, 95% CI –0.12 to –0.04; P<.001) and the SD of activity magnitude (β=–2.05, 95% CI –4.18 to –0.20; P=.02) over the 14 days before the 9-item Patient Health Questionnaire records were negatively associated with depression severity. Conversely, the duration of outgoing calls showed a positive association with depression severity (β=0.05, 95% CI 0.00-0.09; P=.02). Conclusions: Our work shows the important features for future analyses of behavioral markers of mood disorders. However, among outpatients with mild to moderate depressive disorders, the group-level differences from healthy controls in any single modality remain relatively modest. Therefore, future studies need to combine data from multiple modalities to detect more subtle differences and identify individualized signatures. The high dropout rates for longer study periods remain a challenge and limit the generalizability.Peer reviewe
The governance of emerging mobility technologies in Finland: A Q-methodology study
No full textThe recent emergence of numerous smart mobility technologies has raised difficult questions concerning the integration of transport and technology governance. To avoid undesirable sociotechnical trajectories and fill the institutional void that emerging technologies typically face, it is crucial to understand relevant actors' views – to explore the reasons for conflict and find common ground for structuring comprehensive and inclusive deliberation. We applied the Q-methodology to identify and analyse different viewpoints concerning the governance of emerging mobility technologies in Finland. A comprehensive sample of 84 people involved in the development and governance of Mobility-as-a-Service, transport automation and shared e-scooter services in Finland participated in the study. The analysis revealed three viewpoints of major interest. “The Cautious Innovators” prioritise risk aversion over the quick implementation of technologies. “The Enablers” view the development of mobility technologies as an international race and wish to maintain Finland's forerunner position. “The Disappointed Optimists” share the desire for the rapid implementation of new mobility technologies but express severe disappointment about how these technologies are currently governed in Finland. Based on the findings, we highlight challenges with the current governance approach and suggest improvements concerning participatory practices and actor roles. Finally, we lay out directions for future research, which should pay attention to the nuances of actor-level interactions and power relations across dynamic governance networks by utilising a broader base of social science concepts and methods.Peer reviewe
Buyer-supplier relationships in response to climate change risks: The role of innovation capability
No full textIn recent decades, climate change has impacted every aspect of life tremendously, including more extreme weather phenomena, global economy uncertainty, and supply chain disruptions. This causes climate change risks for firms due to increasing regulatory pressures, market shifts toward sustainable products, and demanding stakeholder expectations. To combat these challenges, many companies have adopted climate response strategies to reduce greenhouse gas emissions or to improve their resilience. This thesis focuses on examining how implementing these response strategies and buyer firms’ innovation capability affect their buyer-supplier relationships.
By using empirical approaches such as coded firm announcements and a multinomial logistic regression model, the study found that in response to climate change risks firms are transforming their supply chains favorably through buyer-led collaborations, with mitigation strategies being the dominant driver. Besides, although innovation capability significantly has some influence, its weak effect suggests that firms may prioritize other factors when choosing suppliers, rather than innovation capability alone. Finally, mitigation strategies and innovation capability together did not significantly increase firms’ preference for buyer-led collaborations
Enhancing QoS in 6G networks through multi-IAB relaying strategies with Optimal Path Selection
No full textPublisher Copyright: © 2013 IEEE.The rapid increase in global data traffic requires a new generation of mobile communication technologies to enable seamless and immersive high bandwidth services, with improved Quality of Service (QoS), to the end-user terminals. To achieve this goal, the combination of Millimeter Wave (mmWave) links with Integrated-Access-and-Backhauling (IAB) technology, offers a promising solution. With IAB, the wireless Backhaul Link (BL) between donor Next Generation Node B (gNB) and IAB nodes simplifies the ultra-densification of network elements, reducing the cell sizes and increasing the chances of having a Line-of-Sight (LoS) condition in the last wireless hop towards the User Equipment (UE), which is known as an Access Link (AL). This paper studies the end-to-end (e2e) data rate performance of an IAB-enhanced cellular network deployed in a Manhattan-like urban setting, proposing an optimal path selection scheme to improve the experience of mobile users in dense urban environments. This selection scheme allows a mobile UE to connect to a gNB or an IAB node, ensuring improved Signal-to-Interference-and-Noise-Ratio (SINR) levels and, consequently, higher e2e data rates. Simulation results show notable improvements with the optimal path selection scheme, achieving data rate gains of 4.9-6.6 bps/Hz at the 50th percentile, across various IAB relaying strategies when using mmWave frequency bands with a few hundred MHz of bandwidth. This study emphasizes the significance of mmWave IAB deployments in dense urban areas, with optimized path selection to improve end-user experience in dense urban scenarios in which the probability of LoS condition reduces notably with distance even in small cell network deployments.Peer reviewe
Heikommassa asemassa olevia käyttäjiä kuvaavat persoonat saavutettavien julkisten digitaalisten terveyspalveluiden suunnittelun tueksi
No full textThe wide target audience of public eHealth services poses challenges for their designers. One way to approach these issues is by focusing on the most vulnerable groups to enhance usability and accessibility for all. Many vulnerable groups also share similar challenges, such as cognitive issues. Using personas, a popular user-centred design method, may help to communicate needs of vulnerable groups and foster a broader view of accessibility. This study investigates how to create per-sonas of vulnerable users that support design for all in the context of public eHealth services. A design science research process was used to create a solution for the identified problem: lack of considering vulnerable groups in the design of eHealth and difficulties in sharing user knowledge. To gain understanding of the phenomena, a literature review and ten semi-structured interviews with professionals working in organizations developing public eHealth services were con-ducted. The interview data was analysed using inductive content analysis. Six personas and six visual tables providing overview of the needs of different vulnerable groups were created based on the findings of DigiIN, the project focusing on digital inclusion of vulnerable groups. First versions of personas were demonstrated to designers and feedback was collected for evaluation. After that, the personas were further developed, and some parts of the research findings were represented with tables. The results of this study suggest that personas should represent groups who currently struggle the most with eHealth. These include older adults, immigrants, and people with cognitive impairments. Persona method was already in use in two of the three organizations the interviewed designers represented. In one of the organizations, personas of vulnerable user had been made. However, an important identified issue was that personas were often not used effectively. Designers expressed a preference for human-like personas that reflect both the digital and health-related aspects of eHealth. Ultimately, well-developed personas can complement the involvement of real users by ensuring that the needs of vul-nerable groups are considered throughout the design process, thereby enhancing communication, and fostering inclusive eHealth solutions.Julkisten digitaalisten terveyspalveluiden laaja kohdeyleisö aiheuttaa haasteita niiden suunnittelijoille. Eräs tapa lähestyä ongelmaa on keskittyä kaikkein heikoimmassa asemassa oleviin, jotta voidaan parantaa käytettävyyttä ja saavutettavuutta kaikille käyttäjille. Samankaltaisia ongelmia, kuten kognitiivisia haasteita, esiintyy monilla eri heikommassa asemassa olevilla ryhmillä. Persoonat, tunnettu käyttäjäkeskeisen suunnittelun menetelmä, voivat auttaa kommunikoimaan heikommassa asemassa olevien ryhmien tarpeita ja laajentamaan saavutettavuuskäsitystä. Tässä tutkimuksessa selvitetään, miten luodaan näitä ryhmiä kuvaavia käyttäjäpersoonia, jotka tukevat julkisten sähköisten terveyspalveluiden suunnittelua kaikille. Kehittämistutkimusprosessin avulla suunniteltiin ratkaisu ongel-maan, jossa haavoittuvien ryhmien tarpeet jäävät huomiotta digitaalisten terveyspalveluiden suunnittelussa ja käyttäjätiedon jakaminen on haastavaa. Ilmiön ymmärtämiseksi tehtiin kirjallisuuskatsaus sekä kymmenen puolistrukturoitua suunnittelijoiden haastattelua. Haastatteluaineisto analysoitiin käyttäen induktiivista sisältöanalyysiä. Digitaaliseen osallisuuteen keskittyvän DigiIN-hankkeen tulosten perusteella luotiin kuusi persoonaa sekä kuusi visuaalista taulukkoa, jotka kuvaavat eri heikommassa asemassa olevien ryhmien tarpeita. Persoonien ensimmäiset versiot esiteltiin suunnittelijoille, ja heiltä kerättiin palautetta jatkokehitystä varten. Tutkimuksen tulokset viittaavat siihen, että persoonilla kannattaa kuvata ryhmiä, joilla on eniten haasteita digitaalisten terveyspalveluiden käytössä, kuten ikääntyneitä, maahanmuuttajia ja henkilöitä, joilla on kognitiivisia haasteita. Persoonamenetelmä oli käytössä kahdessa kolmesta osallistuneesta organisaatiosta, joista yhdessä oli jo tehty heikommassa asemassa olevia käyttäjiä kuvaavia persoonia. Keskeiseksi ongelmaksi tunnistettiin, että kehitetyt persoonat jäävät usein hyödyntämättä. Suunnittelijat suosivat inhimillisiä persoonia, jotka kuvaavat digitaalisten terveyspalveluiden käyttöä sekä digitaalisuuden että terveydentilan näkökulmasta. Huolellisesti kehitetyt persoonat voivat täydentää todellisten käyttäjien osallistumista palvelukehitykseen varmistamalla, että heikommassa asemassa olevien ryhmien tarpeet huomioidaan koko suunnitteluprosessin ajan. Persoonat voivat vahvistaa suunnittelijoiden välistä kommunikaatiota ja edistää inklusiivisten ratkaisujen kehittämistä
Kasvojentunnistus tunnistautumisen keinona mobiililaitteilla
No full textBiometriikan käyttö tunnistautumisen keinona mobiililaitteilla on yleistynyt viime vuosina. Kyseinen ilmiö on siirtänyt tunnistautumisen tietopohjaisesta "Mitä käyttäjä tietää?" suuntaan, jossa kysytään "Kuka käyttäjä on?". Teknologioiden kehittyessä on tärkeä selvittää, miksi muutos on tapahtunut ja miten se vaikuttaa tunnistautumiseen.
Tämän kandityön tavoitteena on selvittää, mitä biometrinen tunnistautuminen on ja mitkä ovat sen mahdollisuudet. Työ käy läpi yleisesti tunnistatumisen keinoja, mutta keskittyy kasvojentunnistukseen, joka on yleinen käytössä oleva biometrinen tunnistautumisen keino mobiililaitteilla. Työ on kirjallisuuskatsaus ja käyttää tieteellisiä artikkeleita ja kerää niistä tietoa biometrisestä kasvojentunnistuksesta.
Työ osoittaa, että biometrinen kasvojentunnistus on turvallinen ja käyttäjäystävällinen tapa tunnistautua mobiililaitteelle, mutta nykyisellä teknologialla se ei pysty korvaamaan olemassa olevia tunnistautumisen keinoja, vaan toimii niiden rinnalla helpottaakseen mobiililaitteen käytettävyyttä. Biometrinen kasvojentunnistus on yleisesti turvallisempi tunnistautumisen keino kuin esim. tietoon perustuva salasana, mutta hyökkääjän saadessa käyttäjän kasvotiedot haltuunsa, ovat ne vaarannettu pysyvästi, koska niitä ei voi muuttaa.
Tulevaisuudessa kehityksen tulisi painottua integroituun kaksivaiheeseen tunnistautumiseen, joka voisi varmistaa helpon ja vahvan tunnistautumisen. Teknologian kehittäjien tulee myös keskittyä siihen, että uudet kehitykset eivät eriarvoista eri kansanryhmiä
Disruption Risks and Resilience of Maritime Supply Chains
No full textRecent disruptions to maritime supply chains, including the COVID-19 pandemic, the Suez Canal blockage caused by the Evergreen, and the Red Sea Crisis, have exposed the vulnerability of maritime transport. These events have underscored the need for a deeper understanding of the risks affecting maritime supply chains and the measures required to improve their resilience. This thesis investigates the key disruption risks maritime supply chains face, focusing on both external shocks and systemic weaknesses. Potential strategies to increase system robustness and adaptability are identified. The research also explores how these disruption risks materialize, examining the underlying causes of recent high-impact events. Finally, the ongoing Red Sea Crisis is analyzed, providing insight into challenges faced by maritime logistics. The Red Sea Crisis highlights critical issues, such as chokepoint dependency and geopolitical instability, which are central to the future of global maritime trade
Maanpäällisen lumen vesiarvon kaukokartoitus satelliittimikroaaltoradiometreillä
No full textSeasonal snow cover is an important component of the Earth's hydrological and energy cycles, affecting water resources and climate feedback mechanisms. Snow water equivalent (SWE), representing the water content of a snowpack, is a key characteristic of snow cover. SWE estimates can be retrieved from passive microwave radiometer data. Global satellite-based passive microwave radiometer measurements are available from 1978 onwards allowing construction of long SWE time series. Radiometer-based SWE retrievals can be improved with the assimilation of synoptic snow depth observations. This thesis aims to advance assimilation-based SWE retrieval method with parametrization of snow density and bias correction.
Publication I presents a method for creating climatological spatially and temporally dynamic snow density fields. The effect of post-processing SWE retrieval with these fields is also studied in the publication. Post-processing improves the overestimation of small SWE values and small improvements in the underestimation of large SWE values are also present.
Publication II investigates implementing dynamic snow densities into the SWE retrieval. Similarly to post-processing with dynamic snow densities, implementing them into the retrieval improves the accuracy of (small) SWE estimates. Additionally, the reduction in hemispheric peak snow mass seen when post-processing with dynamic snow densities is smaller when snow densities are implemented into the SWE retrieval. Implementation of dynamic snow densities into SWE retrieval also delays peak snow mass timing and thus improves the seasonal evolution of SWE.
Publication III updates previously studied monthly bias correction method for monthly SWE estimates with new reference data. Monthly bias correction is also expanded to a daily time scale in this publication. Updated monthly bias correction improves monthly estimates and daily bias correction slightly improves the accuracy of large SWE estimates. More importantly adds a significant amount of snow to the hemispheric snow mass estimation.
Together these three studies improve SWE estimations and our ability to monitor seasonal snow cover.Kausittainen lumipeite on tärkeä osa maapallon vedenkiertokulkua ja säteilytasapainoa. Lumen vesiarvo, joka kuvaa lumipeitteen vesipitoisuutta, on keskeinen lumipeitettä kuvaava määre. Lumen vesiarvoa voidaan arvioida passiivimikroaaltokaukokartoituksella. Satelliittimikroaaltoradiometri mittauksia on saatavilla vuodesta 1978 alkaen, mikä mahdollistaa pitkien lumen vesiarvo aikasarjojen laatimisen. Radiometrimittauksiin perustuvia vesiarvo arviota voidaan parantaa hyödyntämällä lumen syvyysmittauksia vesiarvon arvioinnissa. Tämä väitöskirja pyrkii kehittämään lumensyvyys mittauksia hyödyntävää lumen vesiarvon kaukokartoitusmenetelmää parametrisoimalla lumentiheyden sekä harhakorjauksella.
Julkaisu I esittelee menetelmän ajan ja paikan suhteen dynaamisten lumentiheyskenttien luomiseen. Julkaisussa tutkitaan myös näiden lumentiheyskenttien vaikutusta satelliittimikroaalto pohjoisiin lumen vesiarvo arvioihin jälkikäsittelyn avulla. Jälkikäsittely parantaa pienten arvojen yliarviointia sekä tuottaa pieniä parannuksia suurten vesiarvojen aliarviointiin.
Julkaisussa II tutkitaan dynaamisten lumitiheyksien integroimista lumen vesiarvo arviointimenetelmään. Samoin kuin dynaamisilla lumitiheyksillä jälkikäsitellessä myös niiden sisällyttäminen arviointimenetelmään parantaa pienten arvioiden tarkkuutta. Lisäksi pohjoisen pallonpuoliskon lumimassan huippuarvon pieneneminen, joka havaittiin dynaamisilla lumitiheyksillä jälkikäsitellessä, pienenee kun lumentiheydet integroidaan arviointimenetelmään. Dynaamisten lumitiheyksien sisällyttäminen vesi arvo arviointiin myös viivästyttää lumimassan huipun ajoitusta ja parantaa siten arviota kausittaisen lumen kehityksestä.
Julkaisussa III päivitetään kuukausittaisten vesi arvojen harhan korjausmenetelmä uusilla vertailutiedoilla. Harhan korjausmenetelmää laajennetaan myös päivittäiselle aikaskaalalle. Päivitetty kuukausittainen harhakorjaus parantaa kuukausittaisia kaukokartoitus arvioita lumen vesiarvosta. Päivittäinen harhakorjaus parantaa hieman suurten vesiarvojen tarkkuutta ja ennen kaikkea lisää merkittävästi lunta pohjoisen pallonpuoliskon lumimassa-arvioihin.
Yhdessä nämä kolme tutkimusta parantavat satelliittimikroaaltoradiometri mittauksiin pohjautuvia lumen vesiarvoarvioita ja kykyämme tarkkailla kausittaista lumipeitettä
Cross-Taxa Analysis of Long-Term Data Reveals a Positive Biodiversity-Stability Relationship With Taxon-Specific Mechanistic Underpinning
No full textPublisher Copyright: Ecology Letters© 2024 The Author(s). Ecology Letters published by John Wiley & Sons Ltd.Anthropogenic environmental change is altering biodiversity at unprecedented rates, threatening the stability of ecosystem services on which humans depend. However, most of what is known about biodiversity–stability relationships comes from experimental studies making extrapolation to real ecosystems difficult. Here, we ask whether the shape and underlying mechanisms of the biodiversity–stability relationship vary among taxa in real-world communities. Our study harnesses the power of six terrestrial and aquatic long-term monitoring datasets, encompassing entire assemblages at hundreds of georeferenced sites providing 20 years long community measurements, covering a 1200 km latitudinal gradient across Finland. In general, we detect a positive relationship between species richness and stability. Structural equation modelling reveals that this relationship is modified by functional trait community composition, with specific mechanisms varying among the taxa. Our study is among the first to highlight the importance of functional traits in elucidating both general and taxon-specific impacts of biodiversity on community stability.Peer reviewe
Electrochemical Reduction of CO₂ on Molecular Catalyst: Unfolding Operation Parameters Influence on Product Selectivity
No full textThe electrochemical reduction of CO₂ (eCO₂R) using renewable electricity offers a promising way to convert waste CO₂ into valuable chemicals and fuels, achieving a negative carbon emission footprint. Industrializing eCO₂R for chemical production requires durable, selective, and active electrocatalysts capable of generating high current density at low overpotentials. This thesis focuses on the design and development of a cobalt tetraphenyl porphyrin/multi-walled carbon nanotube (CoTPP/MWCNT) composite for eCO₂R to one-carbon (C₁) chemicals and fuels, and the evaluation of this composite in various electrochemical cells. The electrochemical reduction of CO₂ on CoTPP/MWCNT was investigated in two electrochemical cells: H-cell and industrially relevant flow cell. In both electrochemical cells, selected potential values and a temperature range of 20-50°C were investigated in a 0.1 M KHCO3 electrolyte. The local reaction environment during eCO₂R on the composite was investigated using a differential electrochemical mass spectrometry (DEMS) technique. A similar temperature range as in previous studies was employed.
The H-cell studies reveal that the composite produces a mixture of liquid and gas products. The product selectivity strongly depends on the applied potentials and temperatures. At lowest applied temperature, CO₂ is mainly converted to CO and CH3OH while H2 production remains minimal. As the temperature increases H2 production becomes dominant over eCO₂R related products. Flow cell studies reveal that composite mainly produces gas products such as CO and H2 at all applied potentials and temperature. Like H-cell, product selectivity strongly depends on the applied potentials and temperatures. Interestingly, at 20°C and highest applied negative potential, the composite is highly selective for CO formation, reaching a Faradaic efficiency (FE) of 98%. However, increasing the temperature significantly reduces CO selectivity while increasing H2 production. Furthermore, this study demonstrates that the syngas (a mixture of CO and H2) ratio can be controlled by adjusting the temperature.
DEMS studies identify key fragments of reaction products evolving from the electrode/electrolyte interface. Experimental results reveal that onset potential of reaction products is strongly affected by temperature, particularly onset potential of CH3OH formation decreased approximately 300 mV at highest temperature. The reduction of onset potential is economically beneficial for large-scale industrial chemicals production. Overall, DEMS studies enhance our knowledge on the mechanisms of CH3OH and CH4 production on the CoTPP/MWCNT composite.Julkaisun ISBN-tunnuksessa on kirjoitusvirhe.There is a typo in the ISBN of the publication