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Urbanisation and Climate Shape Breeding Phenology in a Subarctic Songbird
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Urbanisation alters ecological conditions in ways that can affect avian reproductive strategies, yet its impacts in high-latitude environments remain underexplored. We investigated how breeding phenology and reproductive success in pied flycatchers (Ficedula hypoleuca) vary across an urban–rural gradient in Arctic Norway, using a combination of long-term data (2007–2018) from a rural site (Lakselvdalen) and comparative data from both rural and urban sites (Tromsø) during 2023–2024. We examined key reproductive metrics—laying date, hatching date, incubation length, clutch size, brood size, and chick loss—and tested their relationships with temperature and precipitation. Results showed earlier laying and hatching over time, closely linked to increasing temperatures. Birds in urban areas laid earlier but exhibited longer incubation periods, delaying hatching and potentially reflecting less favourable microclimatic or ecological conditions. While clutch size increased in warmer years, brood size and fledging success were relatively stable. Chick loss was lower in the urban site, possibly due to reduced predation or disturbance. Our findings suggest that reproductive timing in Arctic flycatchers is advancing with climate warming but that urban conditions may introduce additional constraints, influencing incubation behaviour and reproductive outcomes.Abstract
Urbanisation alters ecological conditions in ways that can affect avian reproductive strategies, yet its impacts in high-latitude environments remain underexplored. We investigated how breeding phenology and reproductive success in pied flycatchers (Ficedula hypoleuca) vary across an urban–rural gradient in Arctic Norway, using a combination of long-term data (2007–2018) from a rural site (Lakselvdalen) and comparative data from both rural and urban sites (Tromsø) during 2023–2024. We examined key reproductive metrics—laying date, hatching date, incubation length, clutch size, brood size, and chick loss—and tested their relationships with temperature and precipitation. Results showed earlier laying and hatching over time, closely linked to increasing temperatures. Birds in urban areas laid earlier but exhibited longer incubation periods, delaying hatching and potentially reflecting less favourable microclimatic or ecological conditions. While clutch size increased in warmer years, brood size and fledging success were relatively stable. Chick loss was lower in the urban site, possibly due to reduced predation or disturbance. Our findings suggest that reproductive timing in Arctic flycatchers is advancing with climate warming but that urban conditions may introduce additional constraints, influencing incubation behaviour and reproductive outcomes
Study of shallow gas and gas hydrate dynamics around the Hinlopen slide: Insights from multi-channel seismic velocity and AVO analysis
Get PDFThe Hinlopen submarine slide located on the northern Svalbard margin is one of the largest submarine slides documented to date. The cause of the slide is associated with destabilizing factors like glacio-tectonic activity, isostacy, gas accumulation, gas hydrate dynamics, and rapid sediment loading in interglacial periods. Free gas accumulation within continental slope sediments is one of the most important factors affecting sediment stability, it can lead to increase in pore pressure and cause overpressured conditions. Accumulation of shallow gas is highly related to the melting of gas hydrates, which can be caused by e.g. glacial isostatic rebound or sea level change. Mapping gas hydrates and shallow gas accumulation in sediments is therefore important in geohazard settings. The main objectives for this project is to establish an efficient seismic processing flow for marine multichannel seismic data, and investigate the potential link between shallow gas, gas hydrates, glacial dynamics and submarine slope stability around the Hinlopen slide, while also conducting an investigation into several seismic anomalies located in the Sophia Basin, where recent academic questions regarding the origin of the anomalies have been raised.
Seismic interpretation and velocity analysis on 2D multi-channel seismic data located north of the Hinlopen slide revealed numerous shallow fluid indicators such as high amplitudes coinciding with low velocity zones, possible migration pathways and gas hydrate presence. On the slope leading out to the slide’s run-out area, base gas hydrate stability zone estimations suggest a gas hydrate composition of methane/propane in fresh- or saltwater conditions on the mid- to lower part of the slope, but a composition of pure methane in freshwater conditions on the upper slope, suggesting gas hydrates formed during a period where glacial meltwater may have saturated the sediments. AVO analysis within the FGZ identified anomalous behaviour suggesting gas presence, and indication of possibly overpressure conditions. In contrast AVO analysis in the GHSZ within the same reflection showed little to no anomalous behaviour. Observations and results largely correspond to similar studies and supports the accepted hypothesis for the area.
Seismic interpretation and velocity analysis of 2D multi-channel data west of the slide area also exhibited several fluid indicators like migration pathways and amplitude anomalies coinciding with low velocity zones. Though it also revealed high seismic anomalies overlying high velocity zones, indicating what is interpreted as a possible basaltic presence
Movements, diving behavior and group fidelity of long-finned pilot whales in Northern Norway
No full textLong-finned pilot whales (Globicephala melas) are widely distributed and abundant throughout the North Atlantic and sightings have appeared to increase in coastal areas in northern Norway over the past decade. However, little is known about the dynamics and ecological drivers of their movements in this region. Therefore, we deployed 11 satellite-linked tags to determine areas of important habitat, investigate dive behavior in terms of depth use, duration and diel patterns, and look for patterns of group fidelity. The tags were deployed during March-August 2023-2024 in Andøya in northern Norway and provided location and dive information. They transmitted data for 8-116 days (mean = 44) and utilized latitudes from 63 to 71°N along the Norwegian coastline. The whales remained almost exclusively on the continental shelf, mostly in areas close to the coast, only occasionally venturing over the shelf break, but rarely into deep oceanic waters (> 2,000 m). Dive profiles from two individuals show that most of the time (75%) was spent at depths close to the surface (<20 m). Most of the dives were between the 200-500 m in depth and averaged 4-10 minutes in duration. When multiple individuals were tagged within an assumed family group, they appeared to travel together almost all the time. When individuals were tagged within super-groups (=large groups consisting of several assumed family groups), but assumed to belong to different family groups, they coordinated movement from a distance, migrating at the same time and able to leave the group and merge back later on. This study provides novel, important information on the behavior and area use of long-finned pilot whales at the current northern limit of their range in the North Atlantic. This work is important as a baseline for how the species might be affected by anthropogenic activities and climate change. Our work also highlights the need for more coordinated efforts to monitor the movements of vulnerable marine predators, particularly in the northeast Atlantic, where their population structure is poorly understood
Modern corneal imaging technology in cataract and refractive surgery -Total corneal astigmatism and corneal epithelial thickness measurements for surgical planning in lens exchange- and laser vision correction surgery
No full textBackground/Aim: The precision and accuracy of corneal imaging technology are crucial in contemporary cataract and refractive surgery. This thesis aims to assess the repeatability and agreement of measurements for total corneal astigmatism (TCA), axial length (AL) and corneal epithelial thickness mapping (ETM) using five modern optical coherence tomography (OCT) devices across various clinical conditions, including normal eyes, post-laser vision correction eyes, and keratoconus (KC).
Methods: We examined 392 eyes with three consecutive measurements using two swept-source (SS) OCTs (Anterion and Casia SS-1000), one spectral-domain (SD) OCT (Avanti), one SS-OCT combined with reflectometry (IOLMaster 700), and one SD-OCT combined with Placido imaging (MS-39). Repeatability was assessed by pooled within-subject standard deviation (Sw), and agreement was analyzed using paired t-tests, Bland-Altman plots, and the tolerance index for agreement (TA).
Results: TCA measurements demonstrated excellent repeatability across all devices. Statistically significant differences in cylinder magnitude were observed for most pairs of devices, except IOLMaster 700 to MS-39 and Anterion to MS-39. Anterion and IOLMaster 700 exhibited high repeatability in AL measurements and the difference between them was not clinically significant. For ETM, Anterion demonstrated higher repeatability compared to Avanti and MS-39. The TA surpassed the cutoff in all sections for all pairs of devices, showing their non-interchangeability.
Conclusions: All devices demonstrated good repeatability in TCA-, AL- and ETM measurements. However, variations and low agreement in cylinder magnitude and ETM were observed, proving their non-interchangeability. On the other hand, AL measurements with Anterion and IOLMaster 700 were interchangeable. We expect our findings to provide valuable insights into tailored approaches based on device characteristics and the patient's condition.Bakgrunn/Mål: Presisjonen og nøyaktigheten til teknologien for avbildning av hornhinnen er avgjørende i moderne grå stær- og refraktiv kirurgi. Denne avhandlingen har som mål å vurdere gjentagbarheten og enigheten i målinger av total hornhinneastigmatisme (TCA), aksiallengde (AL) og kartlegging av tykkelsen på hornhinnens epitel (ETM) ved hjelp av fem moderne optiske kohærens-tomografi (OCT)-enheter under ulike kliniske forhold, inkludert normale øyne, øyne etter laserøyeoperasjon og keratokonus (KC).
Metoder: Vi undersøkte 392 øyne med tre påfølgende målinger ved bruk av to swept-source (SS)-OCT-enheter (Anterion og Casia SS-1000), en spectral-domain (SD)-OCT (Avanti), en SS-OCT kombinert med reflektometri (IOLMaster 700) og en SD-OCT kombinert med Placido-bilde (MS-39). Gjentagbarheten ble vurdert ved hjelp av samlet standardavvik innen subjektet (Sw), og enigheten ble analysert ved hjelp av parede t-tester, Bland-Altman-plott og toleranseindeksen for enighet (TA).
Resultater: Målinger av TCA viste utmerket gjentagbarhet på tvers av alle enheter. Statistisk signifikante forskjeller i sylinderstyrke ble observert for de fleste enhetspar, bortsett fra mellom IOLMaster 700 og MS-39, samt mellom Anterion og MS-39. Anterion og IOLMaster 700 viste høy gjentagbarhet i AL-målinger, og forskjellen mellom dem var ikke klinisk signifikant. For ETM viste Anterion høyere gjentagbarhet sammenlignet med Avanti og MS-39. TA oversteg grenseverdien i alle deler for alle enhetspar, noe som viser at de ikke er utbyttbare.
Konklusjoner: Alle enhetene viste god gjentagbarhet i målinger av TCA, AL og ETM. Imidlertid ble det observert variasjoner og lav enighet i sylinderstyrke og ETM, noe som bekrefter at de ikke er utbyttbare. På den annen side var AL-målingene med Anterion og IOLMaster 700 utbyttbare. Vi forventer at våre funn vil gi verdifulle innsikter for tilpassede tilnærminger basert på enhetenes egenskaper og pasientens tilstand
Photography, plants and care in a changing Arctic
Get PDFSource at https://www.tandfonline.com/journals/rpho20.This paper develops a theoretical analogy between photography and plants and engages with contemporary ideas on photography and care in a posthuman and more than-human-world. The analysis is based on a selection of vernacular archival images from the Svalbard region, recorded by temporary settlers in the Norwegian, Swedish, and Soviet mining towns between the 1920s and 1980s, which are now kept in the Arctic archives. In the High Arctic both plants and humans live under sparse conditions, and even more so under the pressure of the modern extraction of natural and human resources. However, photographs depicting humans and plants in Arctic settlements document relations of care for the self and the environment, protecting native vegetation and the cultivation of imported plants. They also witness the photographer’s role as caretaker, and, later on, the institutional and archival care. The photographic motifs direct our attention towards unnoticed phenomena, thus making them significant both for the contemporary spectator and for posterity. Care is also deeply intertwined with power relations, social structures, and ecological systems, and made it obvious that the photographs in the Arctic archives raise ethical considerations particularly concerning issues of human exploitation and domination, disturbing colonialism, and the collapse of ecosystems. While the photographs lay bare possibilities for new forms of engagement with the photographic material and re-entanglements, they also open towards resistance, collaboration and hope for renewal. The suggested parallels of the life of plants and photography are part of this paper’s contribution to the speculation of a future Arctic with changed life forms, migrating plants and people
“But when I come home…”: How patients with chronic musculoskeletal pain account for their absent pain during naturally occurring clinical consultations
Get PDFWhen patients’ embodied experiences cannot be conveyed to clinicians in real-time, the challenges of reaching a shared understanding between patient and clinician are enhanced. In this study, we explore how patients with chronic musculoskeletal pain manage the situation of knowing that they regularly experience pain, yet exhibit minimal signs of it during clinical consultations. Utilizing a multimethod, conversation analysis approach and an interactional perspective, this paper analyzes 10 naturally occurring consultations at a specialized rehabilitation clinic in Norway. The analysis shows that patients account for the absence of pain by referring to i) specific events, ii) pain tolerance, and iii) pain periods. Such accounts were typically triggered by null findings (i.e., the absence of findings in technological and physical tests) in the physical examination and clinicians’ positive summaries of patients’ bodily conditions. Patients resist clinicians’ positive stance by accounting for absent pain, cautiously challenging the clinicians’ epistemic stance. If clinicians do not pursue patients’ accounts, this might lead to a misalignment between patient and clinician which can obstruct efforts to reach a shared understanding of the pain. These findings may have general relevance for clinical consultations where patients’ symptoms are difficult to measure and validate biomedically. Understanding how patients account for absent pain can enhance clinician-patient communication and improve clinicians’ understanding of patients’ everyday circumstances and thereby improve the outcome of consultations
Female sex hormones and subtypes of breast cancer
Get PDFBakgrunn: Det er gode holdepunkter for at kvinnelige kjønnshormoner har en avgjørende rolle i utviklingen av brystkreft. Subtyper av brystkreft utgjør distinkte sykdomsentiteter og har ulik etiologi, risikofaktorer og prognoser. Disse subtypene er ofte klassifisert som luminal A-lignende, luminal B-lignende, HER2-positiv og trippel-negativ brystkreft (TNBC) basert på immunhistokjemisk undersøkelse. Assosiasjonen mellom kvinnelige kjønnshormoner og subtyper av brystkreft er ikke fullstendig kartlagt.
Mål: Formålet med denne avhandlingen var å undersøke sammenhengen mellom endogene (kroppsmasseindeks [BMI]) og eksogene (p-piller [OC] og hormonbehandling i overgangsalderen [MHT]) kvinnelige kjønnshormoner og subtyper av brystkreft hos norske kvinner, og å undersøke om disse hormonelle faktorene påvirker risikoen for ulike subtyper forskjellig.
Metoder: Denne avhandlingen brukte data fra den norske Kvinner og Kreft-studien (NOWAC) – en prospektiv nasjonal kohort med mer enn 170 000 kvinner. Data om bruk av hormoner og BMI ble samlet inn fra selvadministrerte spørreskjemaer. Insidente tilfeller av brystkreft ble innhentet gjennom kobling til Kreftregisteret, mens Dødsårsaksregisteret supplerte med oppdatert informasjon om dødsårsaker. Cox proporsjonal hasard regresjon ble brukt til å estimere sammenhengen mellom bruk av OC (Paper I), BMI (Paper II) og MHT-bruk (Paper III) og insidens, mortalitet (Paper III) og overlevelse (Paper III) av subtyper av brystkreft.
Resultater: Bruk av kombinasjonspiller (COC) økte risikoen for hormonreseptor-negativ brystkreft, mens bruk av gestagenpiller (POC) var assosiert med hormonreseptor-positiv brystkreft hvis brukt i fem år eller mer. Risikoene ved nåværende bruk av COC varierte mellom brystkreftsubtypene. Overvekt og fedme ved baseline, økende alder ved overvekt og fedme, og økende varighet av overvekt var assosiert med økt risiko for luminal A-lignende brystkreft sammenlignet med normalvektige kvinner. Kvinner med økende BMI-trajektorier hadde høyere risiko for luminal A-lignende kreft sammenlignet med de med en normal og stabil BMI-trajektorie, mens de med avtagende vekt hadde nesten 50% redusert risiko. MHT-bruk var assosiert med økt forekomst og dødelighet fra luminal A-lignende brystkreft, og økt forekomst av luminal B-lignende brystkreft. Blant pasienter med brystkreft var varigheten av østrogen-gestagen terapi (EPT) assosiert med dårligere overlevelse fra luminal A-lignende sykdom, mens EPT-bruk var assosiert med økt overlevelse blant pasienter med TNBC. MHT-bruk påvirket overlevelsen av de ulike subtypene forskjellig.
Konklusjoner: Mens COC-bruk økte risikoen for hormonreseptor-negativ brystkreft, var overvekt og fedme og bruk av POC og MHT assosiert med økt risiko for hormonreseptor-positive subtyper. Forskjeller i overlevelse indikerte heterogenitet i sammenhengene mellom MHT-bruk og progresjon av brystkreft på tvers av subtyper. Disse funnene understreker det komplekse samspillet mellom østrogen og gestagen i brystkreftutvikling. Begrenset statistisk styrke i noen av subgruppe-analysene kan ha påvirket robustheten i resultatene.Background: Substantial evidence emphasizes a pivotal role of female sex hormones in the etiology of breast cancer. Intrinsic molecular subtypes of breast cancer represent distinct disease entities and have different etiological pathways, risk factors and prognosis. These molecular subtypes are commonly cross-classified as luminal A-like, luminal B-like, HER2-enriched, and triple-negative breast cancer (TNBC) based on surrogate clinicopathological criteria. The association between female sex hormones and subtypes of breast cancer is not fully identified.
Aim: The primary objectives of this thesis was to investigate the associations between endogenous (body fatness) and exogenous (oral contraceptives [OCs] and menopausal hormone therapy [MHT]) female sex hormones and subtypes of breast cancer in Norwegian women, and to determine whether these hormonal factors differentially affect the risk of various tumor subtypes.
Methods: This thesis used data from the Norwegian Women and Cancer Study (NOWAC) – a prospective national cohort of more than 170 000 women. Data on exogenous hormone use and body mass index (BMI) were collected from self-administered questionnaires. Incident breast cancer cases were obtained through linkage to the Cancer Registry of Norway, whereas the Cause of Death Registry provided updated information on causes of death. Cox proportional hazard models were employed to estimate associations between OC use (Paper I), body fatness (Paper II), and MHT use (Paper III) with subtypes of breast cancer incidence, mortality (Paper III), and survival (Paper III).
Results: While use of combined OCs (COCs) increased risk of hormone receptor-negative breast cancer, progestin-only OC (POC) use was associated with hormone receptor-positive breast cancer if used for five years or more. The risks of current COC use varied significantly between breast cancer subtypes. Overweight and obesity at baseline, increasing age at the onset of overweight and obesity, and increasing overweight duration were associated with increased risk of luminal A-like breast cancer compared to normal-weight women. Women belonging to trajectories with increasing BMI had a higher risk of luminal A-like cancer compared to those with a normal and stable trajectory, while those with decreasing weight had nearly a 50% reduced risk. MHT use was associated with incident and fatal overall and luminal A-like breast cancer, and incident luminal B-like breast cancer. Among patients with breast cancer, duration of estrogen-progestin therapy (EPT) use was associated with worse survival from luminal A-like disease, whereas EPT use was associated with improved survival among patients with TNBC. Current MHT use was differentially associated with survival across intrinsic-like subtypes.
Conclusions: While COC use increased the risk of hormone receptor-negative breast cancer, body fatness and the use of POCs and MHT increased the risk of hormone receptor-positive subtypes. Moreover, differences in survival indicated heterogeneity in associations between MHT use and breast cancer progression across tumor subtypes. These findings underscore the complex interplay between estrogen and progestins and their role in breast cancer carcinogenesis. Limited statistical power in some of the subgroup analyses may have affected the robustness of the results
Converging perspectives on the processes exacerbating adolescent obesity: An integrative systems approach
Get PDFAdolescent obesity is a complex public health challenge with steadily increasing and variable prevalence among countries. This paper synthesises the driving feedback mechanisms of adolescent obesity studied in the CO-CREATE project, furthering our understanding of the complexity of this issue. Using systems thinking principles and causal loop diagramming, we integrated the following knowledge and perspectives derived from diverse sources into a causal loop diagram (CLD): a systems map generated by adolescents through participatory modelling workshops, a comprehensive literature review, and input from subject-matter experts during validation workshops. We used a structured and iterative approach to include drivers and to identify feedback loops exacerbating adolescent obesity. The CLD identified 27 key feedback loops across four themes: twelve related to the commercial food environment, six to the physical activity environment, four to mental wellbeing and five to social norms. These loops indicate not only diet and physical activity as drivers of obesity but also stress and other emotional and social pressures. Recognising the imperative need to integrate the perspectives and experiences of adolescents into our analysis, this work advocates for the synthesis of experiential insights with empirical research. The integrated CLD can be used as a visual tool that fosters collaboration among stakeholders and engenders a more comprehensive and inclusive system understanding that can provide holistic intervention considerations to tackle adolescent obesity. Additionally, the CLD lays a foundation for subsequent quantitative modelling works to further address this issue and develop context-based approaches to prevention and evaluation of adolescent obesity
Five millennia of mitonuclear discordance in Atlantic bluefin tuna identified using ancient DNA
Get PDFMitonuclear discordance between species is readily documented in marine fishes. Such discordance may either be the result of past natural phenomena or the result of recent introgression from previously seperated species after shifts in their spatial distributions. Using ancient DNA spanning five millennia, we here investigate the long-term presence of Pacific bluefin tuna (Thunnus orientalis) and albacore (Thunnus alalunga) -like mitochondrial (MT) genomes in Atlantic bluefin tuna (Thunnus thynnus), a species with extensive exploitation history and observed shifts in abundance and age structure. Comparing ancient (n = 130) and modern (n = 78) Atlantic bluefin MT genomes from most of its range, we detect no significant spatial or temporal population structure, which implies ongoing gene flow between populations and large effective population sizes over millennia. Moreover, we identify discordant MT haplotypes in ancient specimens up to 5000 years old and find that the frequency of these haplotypes has remained similar through time. We therefore conclude that MT discordance in the Atlantic bluefin tuna is not driven by recent introgression. Our observations provide oldest example of directly observed MT discordance in the marine environment, highlighting the utility of ancient DNA to obtain insights in the long-term persistence of such phenomena
Hydroclimate intensification likely aided glacier survival on Svalbard in the Early Holocene
Get PDFAccelerated Arctic warming and wetting has global impacts, as the region’s glaciers and ice caps
respond to variations in temperature and precipitation, impacting global sea-level change. But as the
observations needed to calibrate models are scarce, predictions cannot confirm if increases in
snowfall can help offset melt. Here, we analyze two 14,000-year-long glacier-fed lake sediment
records from the Svalbard archipelago to examine the response of a resilient ice cap (Åsgardfonna) to
warmer-than-present Holocene Thermal Maximum conditions. End-Member Modelling allowed us to
unmix the diluted grain size signal of rock flour – a widely used proxy for past glacier change, and
surface runoff – an indicator of hydrological intensification. Our findings reveal that Åsgardfonna
survived and may have advanced despite warmer conditions, possibly due to enhanced snowfall
driven by sea-ice loss. This suggests that future increases in precipitation could moderate glacier
retreat in similar settings