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Study of the energy consumption and duration of a Cyber-Physical System reconfiguration in the Arctic Tundra: from experiments on real infrastructure to extensive simulations
Get PDFCyber-Physical systems (CPS) deployed in scarce-resource environments like the Arctic Tundra for in-situ and long-term observation face extreme conditions. Nodes deployed on the field are under a limited energy budget. To save energy and increase their lifetimes, nodes are forced to alternate between short uptime periods and long sleeping periods. Uptime schedules depend notably on observation tasks and are not synchronised.
Nodes of the CPS may collaborate to provide services such as data aggregation, analytics, etc. Due to a lack of network infrastructure, nodes have to rely on peer-to-peer connections to communicate. Nodes are able to communicate only during uptime, when their uptime periods overlap. When dealing with short and non-synchronised uptimes, opportunities for communication can be very low.
Due to the Arctic Tundra conditions, nodes of the CPS are forced to be autonomous for long periods (from 6 months to a year). During these periods, nodes of the CPS have to autonomously adapt to external events by reconfiguring their systems. Due to collaboration, reconfiguration of collaborative nodes must be coordinated.
Due to scarce connectivity within the CPS and its isolation from external systems, a central authority is most of the time unreachable. Nodes must be able to coordinate their reconfiguration with other nodes in a decentralised manner. Due to scarce connectivity, coordinating such reconfiguration between nodes can impose a significant energy consumption overhead on nodes and take a long time to converge.
This manuscript proposes to study the decentralised reconfiguration of a Cyber-Physical system with sleeping nodes. It provides a solution to define and coordinate the execution of decentralised reconfiguration programs between sleeping nodes. Based on this solution, it aims at extensively studying the performances in terms of energy consumption and duration of such reconfiguration according to the Arctic Tundra characteristics.Cyberfysiske systemer (CPS) som brukes i miljøer med knappe ressurser, som den arktiske tundraen, for in-situ- og langtidsobservasjon, står overfor ekstreme forhold. Noder utplassert i felten har et begrenset energibudsjett. For å spare energi og øke levetiden må nodene veksle mellom korte oppetidsperioder og lange soveperioder. Oppetidsplanene avhenger særlig av observasjonsoppgavene og er ikke synkroniserte.
Nodene i CPS kan samarbeide om å tilby tjenester som dataaggregering, analyse osv. På grunn av manglende nettverksinfrastruktur må nodene basere seg på node-til-node-forbindelser for å kommunisere. Nodene kan bare kommunisere i oppetid, når oppetidsperiodene deres overlapper hverandre. Når man har å gjøre med korte og ikke-synkroniserte oppetider, kan mulighetene for kommunikasjon være svært små.
På grunn av forholdene på den arktiske tundraen er nodene i CPS tvunget til å være autonome i lange perioder (fra 6 måneder til ett år). I løpet av disse periodene må nodene i CPS tilpasse seg eksterne hendelser ved å rekonfigurere systemene sine. På grunn av samarbeidet må rekonfigurasjonen av samarbeidende noder koordineres.
På grunn av de begrensede forbindelsesmulighetene i CPS og isolasjonen fra eksterne systemer er det meste av tiden umulig å nå en sentral myndighet. Noder må kunne koordinere rekonfigurasjonen med andre noder på en desentralisert måte. På grunn av den knappe konnektiviteten kan koordinering av slik rekonfigurasjon mellom noder medføre et betydelig energiforbruk og ta lang tid å oppnå.
I dette manuskriptet studeres desentralisert rekonfigurasjon av et cyberfysisk system med sovende noder. Det gir en løsning for å definere og koordinere utførelsen av desentraliserte rekonfigurasjonsprogrammer mellom sovende noder. Basert på denne løsningen tar det sikte på å studere ytelsen i form av energiforbruk og varighet av en slik rekonfigurasjon i henhold til egenskapene til den arktiske tundraen
Grain-scale feedback between deformation mechanisms and metamorphic reactions: Dissolution-precipitation processes in the lower crust (Kågen gabbros)
Get PDFStrain localization within crustal shear zones involves intricate feedback between deformation mechanisms,
metamorphic reactions and fluid circulation. Despite evidence that these high-deformation zones proceed at least
partly through dissolution-precipitation creep, available creep laws so far only account for dislocation creep and/
or solid-state diffusion processes. Deciphering the role and the contribution of dissolution-precipitation creep to
strain accommodation is now required to further understand the rheological behavior of polymineralic crustal
rocks. This study combines high-resolution microstructural and compositional analytical techniques to track the
progressive deformation of the Kågen metagabbros, at and below grain scale. The Kågen metagabbros preserved
a strain and re-equilibration gradient over outcrop-scale, where metamorphic re-equilibrations and fluid infiltration took place at constant pressure and temperature representative of lower crustal conditions (ca. 1 GPa -
660 ± 25 ◦C). The comparison and quantification of chemical and microstructural information in this shear zone,
through pixel-per-pixel and grain-per-grain correlated EPMA and EBSD maps, enables tracking grain-scale
deformation mechanisms as well as the interplay between grain size reduction, mineral reactions, phase mixing and material transfer. Dissolution-precipitation creep appears dominant for strain accommodation in the
Kågen metagabbros shear zone. As deformation progresses, nucleation of new metamorphic minerals (clinopyroxene, plagioclase, amphibole) allow for grain size reduction and compositional homogenization through
dissolution, transport and precipitation processes associated with fluid ingression along grain boundaries.
Intracrystalline plastic deformation is here insignificant for strain accommodation. Thermodynamic modeling
and textural analysis reveal that re-equilibration processes are spatially controlled by microdomains where
equilibrium is reached locally, on a scale of ~100 µm.
This study calls for integrating reactions, dissolution-precipitation processes, fluids and polymineralic assemblages into rheological laws for a reliable assessment of the mechanical evolution of metamorphic rocks
Improving and preserving cardiorespiratory fitness, muscle strength and adiposity through a complex lifestyle intervention in community-dwelling older adults with elevated cardiometabolic risk: study protocol for the RESTART randomised controlled trial
Get PDFIntroduction As the global population ages, the incidence of cardiometabolic diseases and associated healthcare costs rise. There is a critical need for preventive interventions enabling long-lasting treatment effects to address the decline in physical performance and metabolic health among older adults. The RESTART (RE-inventing Strategies for healthy Ageing: Recommendations and Tools) randomised controlled trial (RCT) aims to evaluate whether a complex lifestyle intervention can improve and maintain cardiorespiratory fitness, muscle strength and body composition among older adults with elevated cardiometabolic risk. Methods and analysis This is the study protocol for the RESTART trial, a two-arm, open-label, parallel-group RCT conducted in Tromsø, Norway, targeting adults aged 60–75 with obesity, a sedentary lifestyle and high cardiovascular risk. Participants are block-randomised (1:1) into either an intervention or active control group. The initial intervention phase (12 months) includes: (a) supervised high-intensity aerobic and strength training (≥85% of maximum capacity) performed two times weekly, (b) behavioural counselling based on acceptance and commitment therapy during six group sessions and (c) dietary guidance based on national nutrition recommendations during two group/ two individual sessions. After 12 months, participants are gradually introduced to exercise sessions offered by local organisations and fitness centres, to enable independent maintenance of lifestyle change. The primary outcome is a change in cardiorespiratory fitness (V̇O2max) at 24 months. Secondary and tertiary outcomes include additional parameters potentially sensitive to lifestyle change, such as 1-repetition maximum muscle strength, muscular power, device-measured physical activity levels, body composition, waist circumference, body weight, cognitive function and self-reported health-related quality of life
Prevalence and density of Elaphostrongylus rangiferi larvae in faecal samples of semi-domestic reindeer (Rangifer tarandus tarandus) in Norway 2013-16
Get PDFBackground - The reindeer brainworm, Elaphostrongylus rangiferi, is a protostrongylid parasite of reindeer that has caused severe disease outbreaks in reindeer husbandry. E. rangiferi is considered ubiquitous in Norway, though most published prevalence studies are from Finnmark county only. In the present study, faecal samples were collected over three winter seasons (2013–2016) from eight herds of semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus) distributed all over the reindeer herding area in Norway. Baermann’s technique was used to identify E. rangiferi larvae. The density of larvae was measured by counting and calculating number of larvae per gram faeces (LPG) in positive samples.
Results - E. rangiferi larvae were found in 109 of 355 faecal samples (31%). All herds had positive samples at all sampling sessions. Prevalence in adults (> 1.5 years, n = 176) was 43% with significant difference between herds, varying from 25 to 78%. Prevalence in calves (
Conclusions - This study confirms that E. rangiferi was ubiquitously present in all parts of the reindeer herding area in Norway during the study period. Differences in prevalence between herds were significant, and LPG in herds increased with increasing herd prevalence
Resuscitation from severe accidental hypothermia - An experimental study with special reference to management of hypothermia-induced cardiovascular dysfunction and cardiac arrest
Get PDFSuccessful management of patients suffering accidental hypothermia can be challenged by a circulatory dysfunction associated with impaired cardiac contractility and reduced intravascular volume. Furthermore, effects of medications can be altered during hypothermia. Despite reports demonstrating survival from hypothermic cardiac arrest (HCA) treated with cardiopulmonary resuscitation (CPR) and rewarming with extracorporeal circulation (ECC), the overall outcome remains poor and the level of scientific evidence to guide treatment is low.
In paper I, we compared different fluid regimes in a rat model of ECC rewarming from HCA and found that a colloid priming solution led to less tissue edema, increased circulating blood volume and organ blood flow compared to a crystalloid solution. This illustrates that composition of fluid additions may have importance during ECC rewarming.
Paper II describes effects of ECC rewarming to restore O2 transport and organ blood flow following prolonged (3h) CPR at 27°C in pigs. ECC rewarming restored hemodynamics, O2 extraction ratios and blood flow to most organs compared to baseline pre-hypothermia. O2 delivery and consumption remained significantly reduced. This study adds knowledge to how prolonged HCA affects cardiovascular function and supports the role of ECC rewarming, even after CPR for several hours.
In Paper III we tested different fluid regimes to maintain euvolemia during rewarming in rats. Treatment with a crystalloid and colloid solution both mitigated the post-hypothermic myocardial dysfunction and accumulation of intracellular Ca2+ observed in untreated control animals. These results encourage intravenous fluids therapy to maintain euvolemia during rewarming from hypothermia.
In paper IV we investigated effects of epinephrine to mitigate hypothermia-induced contractile dysfunction in rat cardiomyocytes. The reduced contractile response of cardiomyocytes after rewarming was not mitigated by epinephrine. The same concentration of epinephrine improved contractile function in cardiomyocytes not exposed to hypothermia. We conclude that epinephrine does not mitigate hypothermia-induced contractile dysfunction in cardiomyocytes.Vellykket behandling av pasienter med aksidentell hypotermi kan være utfordrende da effekter av medisiner endres ved lav kroppstemperatur og pasientene kan utvikle en sirkulasjonssvikt assosiert med nedsatt hjertepumpefunksjon og blodvolum. Selv om mange kasuistikker rapporterer overlevelse med godt utfall etter hypoterm hjertestans som behandles med hjerte-lunge-redning (HLR) og oppvarming med ekstrakorporeal sirkulasjon (EKS), er utfallet dårlig for de fleste pasienter og det mangler evidensbasert kunnskap til å veilede klinisk behandling.
I Artikkel I sammenlignet vi ulike væskeregimer i en rottemodell for EKS-oppvarming fra hypoterm hjertestans. Vi fant at å fylle EKS-kretsen med en kolloidløsning sammenlignet med en krystalloidløsning førte til redusert vevsødem, økt blodvolum og organblodgjennomstrømming. Studien illustrerer at komposisjonen av væsketilskudd kan ha betydning ved EKS-oppvarming.
Artikkel II beskriver effekter av EKS-oppvarming til å gjenopprette oksygentransport og organblodgjennomstrømming etter langvarig (3 timer) HLR i nedkjølte (27°C) gris. EKS-oppvarming førte til gjenoppretting av hemodynamiske parametere, oksygenekstraksjonsratio og blodgjennomstrømming i de fleste organer sammenlignet med utgangsverdier målt før nedkjøling. Studien bidrar til økt kunnskap om hvordan kardiovaskulær funksjon påvirkes ved langvarig HLR ved hypotermi, og støtter den viktige rollen til EKS-oppvarming ved denne tilstanden.
I artikkel III testet vi ulike væskeregimer for å opprettholde normalt blodvolum under oppvarming fra hypotermi i en rottemodell. Væsketilførsel med både en kolloidløsning og krystalloidløsning førte til bedring av den reduserte hjertefunksjonen og opphopning av intracellulær kalsium i hjertemuskelceller som ble observert i ubehandlede kontrolldyr. Resultatene støtter bruk av intravenøs væskebehandling for å opprettholde normalt blodvolum under oppvarming fra hypotermi.
I artikkel IV undersøkte vi om adrenalinbehandling førte til bedring av hypotermi-indusert kontraktil dysfunksjon i hjertemuskelceller fra rotter. Vi fant at adrenalin ikke bedret kontraktil funksjon i hjertemuskelceller etter nedkjøling og oppvarming. Den samme konsentrasjonen av adrenalin bedret kontraktil funksjon i hjertemuskelceller som ikke hadde vært nedkjølt. Vi konkluderer med at adrenalinbehandling ikke bedrer hypotermi-indusert kontraktil dysfunksjon i hjertemuskelceller
Navigating Frailty: Older Adults’ Everyday Lives and Home Care Professionals’ Conceptualisations of Frailty – A Life Course Perspective
Get PDFBåde i Norge og i andre land mottar stadig flere mennesker helsetjenester i sine egne hjem. Mange eldre voksne bor også hjemme så lenge som mulig, selv når de bor alene med skrøpelighet og helseutfordringer. Tidligere forskning viser at eldre voksnes erfaringer av skrøpelighet er dynamiske og nyanserte. Samtidig viser forskning også at dominerende masternarrativ om aldring og alderdom har en tendens til å fremstille aldring enten som ‘svekkelse’ eller som ‘suksess’.
I denne avhandlingen forstås skrøpelighet som en subjektiv, relasjonell og dynamisk erfaring. Gjennom å utforske kontinuitet og endring i hverdagslivet til eldre voksne som lever med skrøpelighet, samt hvordan eldre voksne og hjemmetjenesteutøvere navigerer skrøpelighet, er avhandlingens overordnede mål å skape rom for bredere og mer inkluderende masternarrativ om aldring og skrøpelighet.
Avhandlingen er basert på fokusgruppediskusjoner med ansatte i hjemmetjenesten og individuelle intervjuer med eldre voksne som kan ha erfaringer av skrøpelighet. Hver av de ni eldre voksne ble intervjuet tre ganger med fire måneders mellomrom. Ved hjelp av tematisk analyse viser studien hvordan ansatte i hjemmetjenesten konseptualiserer skrøpelighet på ulike, og til tider motstridende måter. Gjennom tematisk analyse, kombinert med narrativ posisjoneringsanalyse fremhever studien videre hvordan eldre voksne balanserer sine styrker og sårbarheter. Høy alder, det å bo alene og det å motta hjemmetjenester påvirker eldre voksnes bruk av tid, samtidig som ulike erfaringer av tid også påvirker hverdagslivet.
Ved å ta i bruk et livsløpsperspektiv utfordrer avhandlingen forestillingene om at skrøpelighet ikke også kan innebære styrke, at eldre voksnes historier hovedsakelig handler om fortiden, og at aldring enten handler om suksess eller svekkelse. Å skape rom for fortellinger i hjemmetjenestepraksis kan gi innsikt i eldre voksnes mangfoldige erfaringer med skrøpelighet.In Norway and other countries, more people than before are receiving health care services in their homes. Many older adults also continue to live at home for as long as possible, even when they live alone with frailty and health challenges. Previous research demonstrates that older adults’ experiences of frailty are dynamic and nuanced. At the same time, research also indicates that dominant master narratives about ageing and old age tend to portray ageing as either ‘decline’ or ‘success’.
In this thesis, frailty is considered to be a subjective, relational and dynamic experience. Through exploring continuity and change in the everyday lives of older adults living with frailty, as well as how older adults and home care professionals navigate frailty, the overarching aim of this thesis is to create spaces for broader and more inclusive cultural narratives of ageing and frailty.
The thesis is based on focus group discussions with home care professionals and individual interviews with older adults living with frailty. Each of the nine older adults was interviewed three times at four-month intervals. Using thematic analysis, the study shows how home care professionals conceptualise frailty in various, but sometimes contradictory, ways. Through thematic analysis combined with narrative positioning analysis, the study further highlights how older adults balance their strengths and vulnerabilities. Being of advanced age, living alone and using home care influence older adults’ use of time, while various temporal experiences also shape their experiences of everyday life. By adopting a life course perspective, the thesis challenges the notions that frailty cannot also involve strength, that older adults’ stories mainly concern the past, and that ageing is either about success or decline. Creating space for storytelling in home care practice can provide insight into older adults’ diverse experiences of frailty
Curiography
Get PDFThis entry introduces curiography as an innovative way of doing research in the era of the Anthropocene. Curiography is an epistemological framework that applies and critically evaluates the philosophical potential of curiosity to practice academic inquiry. It challenges the anthropocentric legacy of ethnographic methodology by inviting its practitioner to move beyond dominating human-centric methods based on rationality. Curiography as a postqualitative epistemological framework encourages innovative methodologies in order to become attentive to earthly relations and humans’ place as part of the world we aim to understand through academic inquiry
Utenforskap og retten til et «godt» psykososialt skolemiljø: Analyse av rettighetens virkning mot utenforskap og bidrag til et velfungerende skole-hjem-samarbeid
Get PDFAvhandlingen er delt inn i to hovedproblemstillinger. Den første problemstillingen handler om hvordan retten til et «godt» psykososialt skolemiljø i opplæringsloven sikrer at barn og unge ikke havner i utenforskap. I denne sammenheng vil det problematiseres hvordan ordlyden «godt» skal tolkes, og hva det er som kan regnes som godt nok – etter gjeldende rett. Den andre problemstillingen tar for seg skole-hjem-samarbeidet, hvor det reises spørsmål om hvor grensene går mellom foreldrenes og skolens ansvar for at barn skal ha det bra
Saturation in Forcing Efficiency and Temperature Response of Large Volcanic Eruptions
Get PDFVolcanic eruptions cause climate cooling due to the reflection of solar radiation by emitted and subsequently produced aerosols. The climate effect of an eruption may last for about a decade and is nonlinearly tied to the amount of injected SO2
from the eruption. We investigate the climatic effects of volcanic eruptions, ranging from Mt. Pinatubo-sized events to supereruptions. The study is based on ensemble simulations in the Community Earth System Model Version 2 (CESM2) climate model applying the Whole Atmosphere Community Climate Model Version 6 (WACCM6) atmosphere model, using a coupled ocean and fixed sea surface temperature setting. Our analysis focuses on the impact of different levels of SO2 injections on stratospheric aerosol optical depth (SAOD), effective radiative forcing (ERF), and global mean surface temperature (GMST) anomalies. We uncover a notable time-dependent decrease in aerosol forcing efficiency (ERF normalized by SAOD) for all eruption SO2
levels during the first posteruption year. In addition, it is revealed that the largest eruptions investigated in this study, including several previous supereruption simulations, provide peak ERF anomalies bounded at -65 W m-2. Further, a close linear relationship between peak GMST and ERF effectively bounds the GMST anomaly to, at most, approximately -10 K. This is consistent across several previous studies using different climate models
Global Marine Flyways Identified for Long-Distance Migrating Seabirds From Tracking Data
Get PDFAim To identify the broad-scale oceanic migration routes (‘marine flyways’) used by multiple pelagic, long-distance migratory seabirds based on a global compilation of tracking data. Location Global. Time Period 1989–2023. Major Taxa Studied Seabirds (Families: Phaethontidae, Hydrobatidae, Diomedeidae, Procellariidae, Laridae and Stercorariidae). Methods We collated a comprehensive global tracking dataset that included the migratory routes of 48 pelagic and long-distance migrating seabird species across the Atlantic, Indian, Pacific and Southern Oceans. We grouped individuals that followed similar routes, independent of species or timings of migration, using a dynamic time warping clustering approach. We visualised the routes of each cluster using a line density analysis and used knowledge of seabird spatial ecology to combine the clusters to identify the broad-scale flyways followed by most pelagic migratory seabirds tracked to-date at an ocean-basin scale. Results Six marine flyways were identified across the world's oceans: the Atlantic Ocean Flyway, North Indian Ocean Flyway, East Indian Ocean Flyway, West Pacific Ocean Flyway, Pacific Ocean Flyway and Southern Ocean Flyway. Generally, the flyways were used bidirectionally, and individuals either followed sections of a flyway, a complete flyway, or their movements linked two or more flyways. Transhemispheric figure-of-eight routes in the Atlantic and Pacific oceans, and a circumnavigation flyway in the Southern Ocean correspond with major wind-driven ocean currents. Main Conclusions The marine flyways identified demonstrate that pelagic seabirds have similar and repeatable migration routes across ocean-basin scales. Our study highlights the need to account for connectivity in seabird conservation and provides a framework for international cooperation