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Browning events in Arctic ecosystems: Diverse causes with common consequences
Get PDFArctic ecosystems are experiencing extreme climatic, biotic and physical disturbance
events that can cause substantial loss of plant biomass and productivity, sometimes at
scales of >1000 km2. Collectively known as browning events, these are key contributors
to the spatial and temporal complexity of Arctic greening and vegetation dynamics. If we
are to properly understand the future of Arctic terrestrial ecosystems, their productivity,
and their feedbacks to climate, understanding browning events is essential. Here we
bring together understanding of browning events in Arctic ecosystems to compare their
impacts and rates of recovery, and likely future changes in frequency and distribution.
We also seek commonalities in impacts across these contrasting event types. We find
that while browning events can cause high levels of plant damage (up to 100% mortality),
ecosystems have substantial capacity for recovery, with biomass largely re-established
within five years for many events. We also find that despite the substantial loss of leaf
area of dominant species, compensatory mechanisms such as increased productivity
of undamaged subordinate species lessen the impacts on carbon sequestration. These
commonalities hold true for most climatic and biotic events, but less so for physical
events such as fire and abrupt permafrost thaw, due to the greater removal of vegetation.
Counterintuitively, some events also provide conditions for greater productivity (greening)
in the longer-term, particularly where the disturbance exposes ground for plant colonisation.
Finally, we find that projected changes in the causes of browning events currently
suggest many types of events will become more frequent, with events of tundra fire and
abrupt permafrost thaw expected to be the greatest contributors to future browning due to
their severe impacts and occurrence in many Arctic regions. Overall, browning events will
have increasingly important consequences for ecosystem structure and function, and for
feedback to climate
Activities for Ocean Literacy
Get PDFThis chapter showcases over 20 examples of ocean literacy activities developed during the Ocean Incubator Network Living Laboratory and beyond (the Foraminifera Box contains more than six activities that can be downloaded freely). The authors of these activities include students, scientists, researchers, educators, linguists, legal scholars, and experts in accessibility. Each activity has been scrutinized through the educational and pedagogical lens of Marcelle Dabbah to ensure its efficacy and relevance. Both teachers and learners can find inspiration in these activities, which are available for download and can be tailored to meet specific learning objectives and classroom needs. Each activity is structured according to an outline developed by Laura Vita, and includes details such as the contributors, activity name, target audience, focus of the activity, learning objectives, and guidance or instructions
The Ocean Incubator Network (OIN) Project and the Toolkit
Get PDFThis chapter serves as the foundational entry point into understanding the Ocean Incubator Network (OIN) Project and this Toolkit as its milestone. Section 1 provides a comprehensive overview of the OIN Project, detailing its vision, objectives, key project results, and milestones. Following this, Sect. 2 explains the purpose of this Toolkit, which stands as a principal milestone of the project. It outlines the structure of the Toolkit and offers a preliminary summary of its contents, setting the stage for detailed exploration in subsequent chapters. In Sect. 3, the chapter concludes with reflections on potential future applications and developments of both the network and the Toolkit.
As an extensive guide endorsed by UNESCO to advance ocean literacy, the publication directly addresses Challenges 9 and 10 of the Ocean Decade
Tilrettelegging for friluftsliv i Nord-Troms
Get PDFNordreisa er den største kommunen i Nord-Troms, med arealer som rommer
et alpint fjellandskap, et viddelandskap, flere dalfører og flere lakseførende
elver. En av disse, Reisaelva, er kjent for sitt vakre landskap og muligheten for
å få storlaksen på kroken. Som del av vassdraget finner vi den største naturattraksjonen i området: Mollisfossen (269 meter fall). Fossen er et turistmål som
betjenes av flere lokale elvebåtselskaper, men fossen kan også nås ved å vandre
langs stien som følger elva. Innerst i Reisadalen er det anlagt en nasjonalpark,
mens elveosen er naturreservat. Kommunen har også en betydelig kystlinje.
Kommunen har cirka 4800 innbyggere, med Storslett som kommunesentrum. Der ligger også et besøkssenter for nasjonalparken. I kommunen er
ymse servicenæringer det største næringsfeltet, mens landbruk og fiske som
var dominerende tidligere, først og fremst foregår i kombinasjon med andre
næringer. Flere reinbeitedistrikter benytter areal i kommunen vår, sommer og
høst. Nordreisa grenser til Guovdageaidnu i sør og Finland i sørøst, og videre
Kvænangen, Skjervøy og Kåfjord. Kommunene utgjør regionen Nord-Troms.
Regionen er preget av å ha hatt en betydelig innvandring fra Finland, noe som
har bidratt til en levende kvenkultur og kvenske kulturminner. Kommunen
ynder derfor å si at den har preg av tre stammers møte
Psoriasis and vitamin D: Insights from a randomised clinical trial, a cross-sectional analysis of the Tromsø Study 2015-16 and a factorial Mendelian randomisation study using the UK Biobank and HUNT
Get PDFAssociation between the skin disease psoriasis and lower serum 25-hydroxyvitamin D (25[OH]D) levels has been found in some studies. Overweight is considered a risk factor for both psoriasis and vitamin D deficiency. Topical vitamin D analogues are routine treatment for psoriasis, but effect of per oral supplementation is not established. This thesis aimed to enhance understanding of the link between serum 25(OH)D and psoriasis in the general population and explore the impact of overweight. Moreover, to investigate whether vitamin D supplementation has any place in the treatment of psoriasis.
In a cross-sectional study using data from the population-based Tromsø7 study we found no statistically significant relationship between serum 25(OH)D and psoriasis, neither lifetime nor active disease. Interaction analyses indicated that high body mass index (BMI) and vitamin D deficiency combined increase the odds of active psoriasis more than the sum of the two, with an estimated 92% higher odds for active psoriasis in subjects with BMI >27.5 kg/m2 and 25(OH)D <25 nmol/L.
In a randomised, double-blind placebo-controlled trial conducted through two winter seasons in Tromsø, we found no effect of vitamin D supplementation on psoriasis severity in subjects with lower serum 25(OH)D. Low baseline severity scores may explain the lack of a measurable effect. Surprisingly, serum 25(OH)D levels in the intervention group increased less-than-expected based on previous experimental data from the same source population, and this may have affected our results.
To follow-up on our findings in Tromsø7, we performed a factorial Mendelian randomisation study using data from two independent population-based cohorts; the UK Biobank and the Trøndelag Health Study. We found no relative excess risk for psoriasis due to interaction between genetically predicted BMI and serum 25(OH)D. Considering the minor differences in actual BMI and serum 25(OH)D between the factorial groups small interaction effects may have been undetected.Assosiasjon mellom hudsykdommen psoriasis og lave serum 25-hydroxyvitamin D (25[OH]D) nivåer er beskrevet i enkelte studier. Overvekt er en risikofaktor for både psoriasis og vitamin D-mangel. Topikale vitamin D-analoger er blant førstevalgene for behandling av psoriasis, men effekt av per orale vitamin D-tilskudd er ikke etablert. Denne avhandlingen hadde som mål å øke forståelsen av forholdet mellom serum 25(OH)D og psoriasis i den generelle populasjonen, utforske hvordan overvekt kan påvirke denne sammenhengen, samt å evaluere hvorvidt vitamin D-tilskudd har noen plass i behandling av psoriasis.
I en tverrsnittsstudie med data fra den befolkningsbaserte Tromsøundersøkelsen (Tromsø7) fant vi ingen signifikant sammenheng mellom serum 25(OH)D og psoriasis. Interaksjonsanalysen indikerte at kombinasjonen av høy kroppsmasse indeks (KMI) og vitamin D mangel økte oddsen for aktiv psoriasis mer enn summen av de to, med estimert 92% høyere odds for aktiv psoriasis hos personer med KMI >27.5 kg/m2 og serum 25(OH)D <25 nmol/L.
I en randomisert, dobbeltblindet, placebo-kontrollert studie gjennomført gjennom to vintersesonger i Tromsø fant vi ingen effekt av vitamin D-tilskudd på alvorlighetsgrad av psoriasis hos personer med lavere serum 25(OH)D nivåer. Mild sykdom ved oppstart av studien kan potensielt forklare mangel på målbar effekt. Til vår overraskelse steg serum 25(OH)D nivåene i intervensjonsgruppa mindre enn forventet basert på tidligere eksperimentelle data fra samme kildepopulasjon. Dette kan også ha påvirket resultatene våre.
For å følge opp funnene våre i Tromsø7, gjennomførte vi en faktoriell mendelsk randomiserings studie med tverrsnittsdata fra to uavhengige befolkningsbaserte kohorter; UK Biobank og Helseundersøkelsen i Trøndelag. Vi fant ingen relativ tilleggsrisiko for psoriasis pga. interaksjon mellom generisk predikert KMI og 25(OH)D. Med tanke på de små forskjellene i målt KMI og 25(OH)D mellom gruppene, kan små interaksjonseffekter ha vært ikke-detekterbare
Toddlers’ imitation and understanding of communicative intentions in various social contexts - The role of social partner type and ostension on toddlers’ imitation and their inferences about communicative intentions
Get PDFChildren are innately adapted to socialize with their caregivers and environment. In the first years of life, they engage in social learning through interactions with others, for instance, by observing and imitating behaviors. They learn most effectively when adults communicate ostensively with them, using eye contact, infant-directed speech, or contingent responsivity. They may even faithfully imitate irrelevant actions to attain a goal instead of selectively omitting them when presented ostensively. Today, children face the challenge of meeting a variety of social interactions, not just responsive adults but also those distracted by smartphone use and new digital partners like social robots. Thus, to better understand early socio-cognitive development, it is important to investigate toddlers’ imitation and understanding of communication in various social interactions. This thesis investigated the role of ostension and type of social partner on toddlers’ imitation and understanding of others’ communication. Study 1 examined 1.5-year-olds’ imitation patterns of selective versus faithful imitation with social adults in the lab and found that faithful imitation was inconsistent across tests and unstable. Study 2 used online imitation methods to test whether toddlers recognize an adult’s smartphone disruption during ostensive communication as incompatible with their expectations of ostensive communication. The results did not support the hypothesis, showing no differences in faithful imitation between toddlers exposed to the smartphone disruption and the control group. Study 3 reviewed research on toddlers’ understanding of ostensive communication and social learning – including imitation – with social robots, showing that they imitate and learn from robots and sometimes understand robot communication. Together, these studies show that while toddlers adaptably imitate various social partners, their understanding of others’ ostensive communication varies. The thesis provides knowledge about toddlers’ social learning, including imitation, in different social contexts. Moreover, it contributes new imitation material for lab and online testing developed for our experimental studies.Barn har en medfødt evne til å inngå i sosiale samspill med sine foreldre og omgivelser. I de første leveårene lærer de via sosial læring, som ofte innebærer observasjon og imitasjon av andres atferd. Småbarn lærer best når voksne kommuniserer ostensivt gjennom øyekontakt, barne-rettet tale eller kontingent respons. De kan også imitere irrelevante handlinger nøyaktig for å oppnå et mål istedenfor å selektivt imitere kun det nødvendige hvis dette presenteres ostensivt. Småbarn møter mange ulike sosiale situasjoner, ikke bare med responsive voksne, men også med de distrahert av smarttelefoner, og digitale sosiale partnere som roboter. Det er derfor viktig med ny kunnskap om hvordan småbarn imiterer og forstår kommunikasjon i ulike sosiale situasjoner for å bedre kunne forstå tidlig sosio-kognitive utvikling. I denne avhandlingen undersøkes rollen ulike sosiale partnere og ostensiv kommunikasjon spiller for småbarns imitasjon og kommunikasjonsforståelse. Studie 1 undersøke 1.5-åringers imitasjonsmønstre (selektiv versus nøyaktig) med sosiale voksne på laben, og viste at nøyaktig imitasjon verken var konsistent på tvers av tester eller stabil. I Studie 2 brukte vi en nettbasert imitasjonstest med deltakelse via datamaskin, for å teste hypotesen at voksnes smarttelefon-forstyrrelser i sosiale samspill bryter med småbarns forventinger om ostensiv kommunikasjon. Resultatene støttet ikke hypotesen, ettersom vi ikke fant noen forskjeller i nøyaktig imitasjon mellom eksperimentgruppen som observerte smarttelefonforstyrrelser, og kontrollgruppen. I studie 3 undersøkte vi tidligere forskning om småbarns forståelse av og evne til å lære og imitere sosiale roboter. Studien viste at småbarn kan imitere roboter, og i noen situasjoner, men ikke alle, forstå roboters ostensive kommunikasjon. Samlet viser studiene at barn kan imitere ulike sosiale partnere, men at deres forståelse av andres ostensive kommunikasjon er mer sammensatt. Avhandlingen bidrar med ny kunnskap om småbarns sosiale læring, inkludert imitasjon, i ulike sosiale situasjoner. I tillegg, bidrar den med nyutviklede imitasjonsmaterialer for lab og nettbasert testing
The Atlantification process in Svalbard: a broad view from the SIOS Marine Infrastructure network (ARiS)
Get PDFArctic marine systems are vital to the Earth’s ecological and climatic balance and harbour a unique biodiversity adapted to extreme conditions. However, they are under unprecedented threat from climate change, in particular from “Atlantification”, i.e., the loss of sea ice and the increasing influence of Atlantic Water (AW) in this region. Long-term observatories are crucial to detect even small changes in these dynamic ecosystems. Svalbard, with its easily accessible infrastructure, is a strategic location for studying these changes. We have identified marine time series that clearly illustrate the signature of Atlantification in the Svalbard region over the last two decades. These time series provide insight into the propagation of AW and the interaction between the continental slope, the shelf and the fjord systems. Seasonal and multi-year temperature and salinity patterns illustrate the varying influence of AW, with long-term variability showing, among others, a freshening phase since 2018, possibly related to North Atlantic freshwater anomalies
Impact of Gut Microbiome Modulating Interventions on Fecal Metabolome of Infants: A Systematic Review and Quality Assessment
Get PDFSource at https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/full/10.1002/pmic.202400150.The development of the gut microbiome in infancy is a vulnerable process that may be perturbed by antibiotics or supported by probiotics. Although effects of these “biotics” have been well-studied through DNA sequencing, it remains unclear how the resulting compositional changes affect the microbiome metabolic functions. Additionally, limits in method standardization require careful quality assessment of studies reporting fecal metabolome. We conducted a systematic search in Embase and MEDLINE for studies describing fecal metabolites from term and near-term infants, together with anti-, pre-, or probiotic intervention. The search identified 680 articles, of which 60 were assessed for eligibility and 21 were included. We first developed operational checklists for transparent and reproducible reporting and evaluated the quality of metabolomic methodologies. This analysis supported our aim to summarize changes in the fecal metabolome induced by biotic interventions. Despite a varying quality of metabolomic methodology, we identified similarities in the fecal metabolome profiles in response to specific biotic interventions. Among the most frequently observed metabolites, which were consistently reported to be altered after biotic interventions, were bile acids, aromatic amino acids, and short-chain fatty acids. We conclude with a discussion on appropriate experimental design, controls, and metabolomics reporting to guide future research permitting meta-analyses
Leveraging synergies between UAV and Landsat 8 sensors to evaluate the impact of pale lichen biomass on land surface temperature in heath tundra ecosystems
Get PDFPale terricolous lichens are a vital component of Arctic ecosystems, significantly contributing to carbon balance, energy regulation, and serving as a primary food source for reindeer. Their characteristically high albedo also impacts land surface temperature (LST) dynamics across various spatial scales. However, remote sensing of lichens is challenging due to their complex spectral signatures and large spatial variations in coverage and biomass even within local landscape scales. This study evaluates the influence of pale lichens on LST at local and landscape scales by integrating RGB, multispectral, and thermal infrared imagery from an Unmanned Aerial Vehicle (UAV) with multi-temporal Landsat 8 thermal data. An Extreme Gradient Boosting algorithm was employed to map pale lichen biomass, areal extent, and the occurrence of major plant functional types in the sub-arctic heath tundra landscape in the Jávrrešduottar and Sieiddečearru areas on the Finland-Norway border. Generalized Additive Models (GAMs) were used to elucidate the factors affecting LST. The UAV model accurately predicted pale lichen biomass (R2 0.63) and vascular vegetation cover (R2 0.70). GAMs revealed that pale lichens significantly influence thermal regimes, with increased biomass leading to decreased LST, an effect more pronounced at the landscape scale (deviance explained 47.26 % and 65.8 % for local and landscape models, respectively). Pale lichen biomass was identified as the second most important variable affecting LST at both scales, with elevation being the most important variable. This research demonstrates the capability of UAV-derived models to capture the heterogeneous and fine-scale structure of tundra ecosystems. Furthermore, it underscores the effectiveness of combining high spatial resolution UAV and high temporal resolution satellite platforms. Finally, this study highlights the pivotal role of pale lichens in Arctic thermal dynamics and showcases how advanced remote sensing techniques can be used for ecological monitoring and management
Associations of heart rate, cognitive function, and retinal vascular calibers with glomerular filtration rate (GFR) and age-related GFR decline in a healthy general population
Get PDFKronisk nyresykdom er en økende global helseutfordring, mye som følge av en aldrende befolkning samt bedre behandlinger av kroniske sykdommer som øker overlevelsesraten. Nyrefunksjonen, vurdert ved glomerulær filtrasjonsrate (GFR), avtar naturlig med alderen, men dette tas imidlertid ikke hensyn til i definisjonen av kronisk nyresykdom. Dette kan føre til overdiagnostisering hos personer med fysiologisk aldersrelatert fall i GFR og underdiagnostisering hos dem med akselerert fall i nyrefunksjon som kunne hatt nytte av tidlig intervensjon. Sympatisk nervesystemaktivitet spiller en sentral rolle i reguleringen av nyrefiltrasjon og hjertefrekvens. Nyrene, hjernen og retina har lignende mikrovaskulære strukturer og påvirkes av felles risikofaktorer. Målet med avhandlingen var å undersøke markører for vaskulær dysfunksjon, inkludert forhøyet hjertefrekvens, GFR, albumin-til-kreatinin-ratio (AKR) og retinamålinger, og deres sammenheng med aldersrelatert og akselerert GFR-fall samt kognitiv funksjon. GFR kan estimeres (eGFR) eller måles (mGFR). Selv om eGFR er mest brukt, er det mindre nøyaktig enn mGFR, da det påvirkes av faktorer som ikke er relatert til GFR og det er mer upresist i normalområdet for nyrefunksjon. I Renal Iohexol Clearance Survey (RENIS), en populasjonsstudie som fulgte 1627 friske individer i 11 år, har vi målt GFR flere ganger ved iohexol-clearance. Disse dataene er koblet med kognitive tester og retinamålinger fra den sjette Tromsøundersøkelsen. Studien viste at hjertefrekvens, en lett tilgjengelig kardiovaskulær biomarkør, var uavhengig assosiert med mGFR-fall og kan potensielt brukes til å identifisere personer i risiko for akselerert nyrefunksjonstap. Selv om det er en kjent sammenheng mellom nyresykdom og kognitiv dysfunksjon, ble det ikke funnet signifikante sammenhenger i den generelle friske befolkningen. Retinamålinger var derimot signifikant assosiert med både aldersrelatert og akselerert mGFR-fall. Dette tyder på at retina, som kan undersøkes ikke-invasivt, kan fungere som en markør for mikrovaskulær helse i nyrene. Fremtidige studier bør utforske de underliggende mekanismene bak disse funnene.Chronic kidney disease (CKD) is a growing global health challenge driven by an aging population and improved survival rates from chronic illnesses due to advancements in treatments. Kidney function, assessed with glomerular filtration rate (GFR), naturally declines with age. However, the current definition of CKD does not account for physiological age-related GFR decline. This can potentially result in overdiagnosis of healthy individuals and underdiagnosis of those at risk for progressive CKD who could benefit from timely intervention. Sympathetic nervous system activity, a key regulator of kidney filtration, also influences heart rate. Furthermore, the kidney, brain, and retina share similar microvascular structures and are affected by shared risk factors. We aimed to evaluate markers of vascular dysfunction, such as elevated heart rate, GFR, albumin-to-creatinine ratio (ACR), and retinal measurements, and their associations with age-related and accelerated GFR decline and cognitive function. GFR can be estimated (eGFR) or measured (mGFR). While eGFR is widely used, its accuracy is affected by non-GFR-related factors and is less precise. In the Renal Iohexol Clearance Survey (RENIS), a population-based study that followed 1627 healthy individuals over 11 years, GFR was repeatedly measured using iohexol clearance. The RENIS data were coupled with cognitive test results and retinal measurements from the sixth Tromsø study. Heart rate, a simple and non-invasive cardiovascular biomarker, was found to be an independent predictor of mGFR decline. Furthermore, it may be a useful biomarker to identify persons at risk of accelerated mGFR decline. Despite established associations between end-stage renal disease and cognitive impairments, no significant associations were found between mGFR, ACR, and cognitive performance in the healthy population. Retinal vessel measurements were significantly associated with age-related and accelerated mGFR decline, suggesting non-invasive retinal imaging as a potential proxy for kidney microvascular dysfunction. Further investigation is needed to assess these relationships and underlying mechanisms