Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 446
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 120(20): e2220924120, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155853

RESUMO

Warming of the ocean waters surrounding Greenland plays a major role in driving glacier retreat and the contribution of glaciers to sea level rise. The melt rate at the junction of the ocean with grounded ice-or grounding line-is, however, not well known. Here, we employ a time series of satellite radar interferometry data from the German TanDEM-X mission, the Italian COSMO-SkyMed constellation, and the Finnish ICEYE constellation to document the grounding line migration and basal melt rates of Petermann Glacier, a major marine-based glacier of Northwest Greenland. We find that the grounding line migrates at tidal frequencies over a kilometer-wide (2 to 6 km) grounding zone, which is one order of magnitude larger than expected for grounding lines on a rigid bed. The highest ice shelf melt rates are recorded within the grounding zone with values from 60 ± 13 to 80 ± 15 m/y along laterally confined channels. As the grounding line retreated by 3.8 km in 2016 to 2022, it carved a cavity about 204 m in height where melt rates increased from 40 ± 11 m/y in 2016 to 2019 to 60 ± 15 m/y in 2020 to 2021. In 2022, the cavity remained open during the entire tidal cycle. Such high melt rates concentrated in kilometer-wide grounding zones contrast with the traditional plume model of grounding line melt which predicts zero melt. High rates of simulated basal melting in grounded glacier ice in numerical models will increase the glacier sensitivity to ocean warming and potentially double projections of sea level rise.

2.
Proc Natl Acad Sci U S A ; 119(10)2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35193940

RESUMO

Subglacial hydrologic systems regulate ice sheet flow, causing acceleration or deceleration, depending on hydraulic efficiency and the rate at which surface meltwater is delivered to the bed. Because these systems are rarely observed, ice sheet basal drainage represents a poorly integrated and uncertain component of models used to predict sea level changes. Here, we report radar-derived basal melt rates and unexpectedly warm subglacial conditions beneath a large Greenlandic outlet glacier. The basal melt rates averaged 14 mm ⋅d-1 over 4 months, peaking at 57 mm ⋅d-1 when basal water temperature reached +0.88 ∘C in a nearby borehole. We attribute both observations to the conversion of potential energy of surface water to heat in the basal drainage system, which peaked during a period of rainfall and intense surface melting. Our findings reveal limitations in the theory of channel formation, and we show that viscous dissipation far surpasses other basal heat sources, even in a distributed, high-pressure system.

3.
Proc Natl Acad Sci U S A ; 119(52): e2207024119, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36534802

RESUMO

Global warming accelerates melting of glaciers and increases the supply of meltwater and associated inorganic particles, nutrients, and organic matter to adjacent coastal seas, but the ecosystem impact is poorly resolved and quantified. When meltwater is delivered by glacial rivers, the potential impact could be a reduction in light and nutrient availability for primary producers while supplying allochthonous carbon for heterotrophic processes, thereby tipping the net community metabolism toward heterotrophy. To test this hypothesis, we determined physical and biogeochemical parameters along a 110-km fjord transect in NE Greenland fjord, impacted by glacial meltwater from the Greenland Ice Sheet. The meltwater is delivered from glacier-fed river outlets in the inner parts of the fjord, creating a gradient in salinity and turbidity. The planktonic primary production was low, 20-45 mg C m-2 d-1, in the more turbid inner half of the fjord, increasing 10-fold to around 350 mg C m-2 d-1 in the shelf waters outside the fjord. Plankton community metabolism was measured at three stations, which displayed a transition from net heterotrophy in the inner fjord to net autotrophy in the coastal shelf waters. Respiration was significantly correlated to turbidity, with a 10-fold increase in the inner turbid part of the fjord. We estimated the changes in meltwater input and sea ice coverage in the area for the last 60 y. The long-term trend and the observed effects demonstrated the importance of freshwater runoff as a key driver of coastal ecosystem change in the Arctic with potential negative consequences for coastal productivity.


Assuntos
Ecossistema , Estuários , Processos Heterotróficos , Groenlândia , Processos Autotróficos , Plâncton , Camada de Gelo
4.
Proc Biol Sci ; 291(2017): 20232264, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38378147

RESUMO

Complex incubation strategies have evolved to solve the trade-off between parent survival and care for their eggs with often brief departures (recesses) that maximize egg survival, and infrequent extended recesses maximizing adult condition. Here we examined incubation behaviour of sanderlings (Calidris alba), a species that exhibits both biparental and uniparental incubation behaviour. During 11 breeding seasons in Greenland, we have quantified incubation variability with thermologgers placed in nests. We estimated the impact of environmental conditions and individual characteristics on the occurrence and the duration of recesses. We found that extended recesses are a unique feature of uniparentals, and their frequency and duration increased in colder temperatures. The relationship was mediated by body condition, with individuals in poor condition performing longer extended recesses in colder temperatures. This suggests that extended recesses may represent a shift towards self-maintenance at the expense of the egg care, allowing birds to continue incubating under unfavourable conditions. Our study illustrates how extended recesses may be a key breeding strategy to overcome high energetic costs associated with incubation. Quantifying such behavioural flexibility paves the way for tracking future behavioural responses of individuals in the face of changing environments.


Assuntos
Charadriiformes , Humanos , Animais , Temperatura , Aves/fisiologia , Temperatura Baixa , Cruzamento
5.
New Phytol ; 242(6): 2845-2856, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623034

RESUMO

Leaf venation is a pivotal trait in the success of vascular plants. Whereas gymnosperms have single or sparsely branched parallel veins, angiosperms developed a hierarchical structure of veins that form a complex reticulum. Its physiological consequences are considered to have enabled angiosperms to dominate terrestrial ecosystems in the Late Cretaceous and Cenozoic. Although a hierarchical-reticulate venation also occurs in some groups of extinct seed plants, it is unclear whether these are stem relatives of angiosperms or have evolved these traits in parallel. Here, we re-examine the morphology of the enigmatic foliage taxon Furcula, a potential early Mesozoic angiosperm relative, and argue that its hierarchical vein network represents convergent evolution (in the Late Triassic) with flowering plants (which developed in the Early Cretaceous) based on details of vein architecture and the absence of angiosperm-like stomata and guard cells. We suggest that its nearest relatives are Peltaspermales similar to Scytophyllum and Vittaephyllum, the latter being a genus that originated during the Late Triassic (Carnian) and shares a hierarchical vein system with Furcula. We further suggest that the evolution of hierarchical venation systems in the early Permian, the Late Triassic, and the Early Cretaceous represent 'natural experiments' that might help resolve the selective pressures enabling this trait to evolve.


Assuntos
Evolução Biológica , Magnoliopsida , Filogenia , Folhas de Planta , Magnoliopsida/anatomia & histologia , Magnoliopsida/fisiologia , Folhas de Planta/anatomia & histologia , Fósseis/anatomia & histologia , Feixe Vascular de Plantas/anatomia & histologia
6.
Glob Chang Biol ; 30(1): e17087, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273494

RESUMO

Increasing temperatures and winter precipitation can influence the carbon (C) exchange rates in arctic ecosystems. Feedbacks can be both positive and negative, but the net effects are unclear and expected to vary strongly across the Arctic. There is a lack of understanding of the combined effects of increased summer warming and winter precipitation on the C balance in these ecosystems. Here we assess the short-term (1-3 years) and long-term (5-8 years) effects of increased snow depth (snow fences) (on average + 70 cm) and warming (open top chambers; 1-3°C increase) and the combination in a factorial design on all key components of the daytime carbon dioxide (CO2 ) fluxes in a wide-spread heath tundra ecosystem in West Greenland. The warming treatment increased ecosystem respiration (ER) on a short- and long-term basis, while gross ecosystem photosynthesis (GEP) was only increased in the long term. Despite the difference in the timing of responses of ER and GEP to the warming treatment, the net ecosystem exchange (NEE) of CO2 was unaffected in the short term and in the long term. Although the structural equation model (SEM) indicates a direct relationship between seasonal accumulated snow depth and ER and GEP, there were no significant effects of the snow addition treatment on ER or GEP measured over the summer period. The combination of warming and snow addition turned the plots into net daytime CO2 sources during the growing season. Interestingly, despite no significant changes in air temperature during the snow-free time during the experiment, control plots as well as warming plots revealed significantly higher ER and GEP in the long term compared to the short term. This was in line with the satellite-derived time-integrated normalized difference vegetation index of the study area, suggesting that more factors than air temperature are drivers for changes in arctic tundra ecosystems.


Assuntos
Dióxido de Carbono , Ecossistema , Estações do Ano , Dióxido de Carbono/química , Temperatura , Neve , Tundra , Regiões Árticas , Solo/química
7.
Environ Sci Technol ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321867

RESUMO

The Arctic is undergoing rapid changes, and biota are exposed to multiple stressors, including pollution and climate change. Still, little is known about their joint impact. Here, we investigated the cumulative impact of crude oil, warming, and freshening on the copepod species Calanus glacialis and Calanus finmarchicus. Adult females were exposed to ambient conditions (control; 0 °C + 33 psu) and combined warming and freshening: 5 °C + 27 psu (Scenario 1), 5 °C + 20 psu (Scenario 2) for 6 days. All three conditions were tested with and without dispersed crude oil. In Scenario 1, fecal pellet production (FPP) significantly increased by 40-78% and 42-122% for C. glacialis and C. finmarchicus, respectively. In Scenario 2, FPP decreased by 6-57% for C. glacialis, while it fluctuated for C. finmarchicus. For both species, oil had the strongest effect on FPP, leading to a 68-83% reduction. This overshadowed the differences between climatic scenarios. All variables (temperature, salinity, and oil) had significant single effects and several joint effects on FPP. Our results demonstrate that Arctic copepods are sensitive to environmentally realistic concentrations of crude oil and climate change. Strong reductions in feeding can reduce the copepods' energy content with potential large-scale impacts on the Arctic marine food web.

8.
Int J Equity Health ; 23(1): 11, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254148

RESUMO

BACKGROUND: Cancer is a major global health concern. Unfortunately, Indigenous populations such as Greenlanders living in Denmark, face significant disparities in cancer risk, incidence, diagnosis, care quality, and outcomes. In Denmark, vulnerable Greenlanders face challenges accessing cancer screening. The aim of this study was to explore their perceptions of cancer, barriers to participation in cancer screening, and potential for developing a tailored intervention. METHODS: This qualitative study was based on participant observations and qualitative interviews. The sample comprised 46 participants from four distinct drop-in centres. Of these, 28 were vulnerable Greenlanders (19 women and 9 men), 9 were staff members (6 women and 3 men), and 6 were relatives (4 women and 2 men). The data were analysed through inductive content analysis. RESULTS: Vulnerable Greenlanders in Denmark believed they were responsible for their own health and were generally satisfied with the healthcare system. However, they found it challenging to manage their own health and many depended on support from others. Fear of cancer and death shaped their attitudes towards screening. CONCLUSION: For vulnerable Greenlanders in Denmark participation in cancer screening programmes was positively viewed for most but could be challenging. Different intervention ideas raised by the vulnerable Greenlanders, relatives and staff members could guide the development of strategies to increase participation rates.


Assuntos
Detecção Precoce de Câncer , Neoplasias , Feminino , Humanos , Masculino , Medo , Groenlândia , Neoplasias/diagnóstico , Pesquisa Qualitativa
9.
Environ Res ; 252(Pt 4): 119021, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38685293

RESUMO

Demand for n-3 polyunsaturated fatty acids (n-3 PUFAs) exceeds supply. Large-scale studies on effects of season and geography of n-3 PUFAs in marine fish from the Northeast Atlantic Ocean (NEAO) may be used to optimize utilization and improve nutrition security. Using a sinusoid model, seasonal cycles of n-3 PUFAs were determined and found to be species-specific and clearly pronounced for the pelagic zooplankton feeding species. The Greenland halibut showed very little seasonal variation. The n-3 PUFA content in North Sea autumn-spawning (NSAS) herring peaked in summer, while Norwegian spring-spawning (NSS) herring and mackerel had their peak in autumn. A time shift of peaks in n-3 PUFAs between the two herring stocks was detected, likely due to different spawning strategies in addition to a delay of n-3 PUFAs flux in the northern regions of the NEAO. This study demonstrates that consideration of nutrient contents, such as n-3 PUFAs, when organizing and structuring fishery approaches may improve overall nutritional yield. Based on total annual Norwegian fish landings and seasonal variation in n-3 PUFA contents, n-3 PUFAs yield could theoretically be increased from 13.79 kilo ton per year from the current fishing tactics, to 15.54 if the pelagic species were only caught during the time of their seasonal n-3 PUFA peaks. Pelagic fish is a good source for dietary n-3 PUFAs, but harvest timing will also influence n-3 PUFAs intake by human consumers. One portion of fatty fish harvested during winter/spring may not meet the weekly intake reference nutritional guidelines for n-3 PUFAs. Marine n-3 PUFAs yields also varied geographically and decreased southwards, with the lowest values in Skagerrak. This study can serve as a model to understand patterns of reproductive cycles and geographical distribution of n-3 PUFAs in fatty fish from the NEAO and the novel approach may be useful to support sustainable, seasonal fishing programmes for optimization of n-3 PUFAs yields.


Assuntos
Ácidos Graxos Ômega-3 , Peixes , Estações do Ano , Animais , Oceano Atlântico , Ácidos Graxos Ômega-3/análise , Peixes/metabolismo , Modelos Biológicos
10.
Scand J Public Health ; : 14034948241245184, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600438

RESUMO

AIMS: Health research in Greenlanders is challenged by a small population, few dedicated researchers and limited funding. Some research areas have proven impactful but gaps in knowledge are unknown. We aimed to quantify health research in Greenland, providing insights for researchers, policymakers and funding agencies to guide future research. METHODS: We identified all peer-reviewed health research publications with the term 'Greenland***' in title or abstract from 2001 to 2020 through the platform entitled The Lens. Our bibliometric analysis included number of publications, publication rate, research types, research topics, citations and author affiliations, as well as funding. RESULTS: From 2001 to 2020, a total of 640 health research publications concerning Greenland or Greenlanders were identified, with an average annual publication growth rate of 2.9%. The major health research topics studied in Greenland were infectious diseases, environmental health and general health. Several research fields, including rheumatology, nephrology and dermatology among others proved understudied at best. Three Danish universities contributed with 33% of all publications, with the International Journal of Circumpolar Health (N=176, 28%) being the top journal destination. The most productive author had 119 article authorships during the period. CONCLUSION: During the past 20 years, Greenland's annual publication rate has been steadily increasing, with an average of 32 articles about health research published each year, which is a higher publication rate than world average. The health research in Greenland is primarily epidemiologic with infectious disease being the most studied research area. Most publications were anchored in Denmark and centred around a few highly productive authors.

11.
Proc Natl Acad Sci U S A ; 118(2)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33372140

RESUMO

Zachariae Isstrøm (ZI) and Nioghalvfjerdsfjorden (79N) are marine-terminating glaciers in northeast Greenland that hold an ice volume equivalent to a 1.1-m global sea level rise. ZI lost its floating ice shelf, sped up, retreated at 650 m/y, and experienced a 5-gigaton/y mass loss. Glacier 79N has been more stable despite its exposure to the same climate forcing. We analyze the impact of ocean thermal forcing on the glaciers. A three-dimensional inversion of airborne gravity data reveals an 800-m-deep, broad channel that allows subsurface, warm, Atlantic Intermediate Water (AIW) (+1.[Formula: see text]C) to reach the front of ZI via two sills at 350-m depth. Subsurface ocean temperature in that channel has warmed by 1.3[Formula: see text]C since 1979. Using an ocean model, we calculate a rate of ice removal at the grounding line by the ocean that increased from 108 m/y to 185 m/y in 1979-2019. Observed ice thinning caused a retreat of its flotation line to increase from 105 m/y to 217 m/y, for a combined grounding line retreat of 13 km in 41 y that matches independent observations within 14%. In contrast, the limited access of AIW to 79N via a narrower passage yields lower grounded ice removal (53 m/y to 99 m/y) and thinning-induced retreat (27 m/y to 50 m/y) for a combined retreat of 4.4 km, also within 12% of observations. Ocean-induced removal of ice at the grounding line, modulated by bathymetric barriers, is therefore a main driver of ice sheet retreat, but it is not incorporated in most ice sheet models.

12.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34518222

RESUMO

Reconstruction of the North Atlantic jet stream (NAJ) presents a critical, albeit largely unconstrained, paleoclimatic target. Models suggest northward migration and changing variance of the NAJ under 21st-century warming scenarios, but assessing the significance of such projections is hindered by a lack of long-term observations. Here, we incorporate insights from an ensemble of last-millennium water isotope-enabled climate model simulations and a wide array of mean annual water isotope ([Formula: see text]O) and annually accumulated snowfall records from Greenland ice cores to reconstruct North Atlantic zonal-mean zonal winds back to the 8th century CE. Using this reconstruction we provide preobservational constraints on both annual mean NAJ position and intensity to show that late 20th- and early 21st-century NAJ variations were likely not unique relative to natural variability. Rather, insights from our 1,250 year reconstruction highlight the overwhelming role of natural variability in thus far masking the response of midlatitude atmospheric dynamics to anthropogenic forcing, consistent with recent large-ensemble transient modeling experiments. This masking is not projected to persist under high greenhouse gas emissions scenarios, however, with model projected annual mean NAJ position emerging as distinct from the range of reconstructed natural variability by as early as 2060 CE.

13.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33972430

RESUMO

The relative warmth of mid-to-late Pleistocene interglacials on Greenland has remained unknown, leading to debates about the regional climate forcing that caused past retreat of the Greenland Ice Sheet (GrIS). We analyze the hydrogen isotopic composition of terrestrial biomarkers in Labrador Sea sediments through interglacials of the past 600,000 y to infer millennial-scale summer warmth on southern Greenland. Here, we reconstruct exceptionally warm summers in Marine Isotope Stage (MIS) 5e, concurrent with strong Northern Hemisphere summer insolation. In contrast, "superinterglacial" MIS11 demonstrated only moderate warmth, sustained throughout a prolonged interval of elevated atmospheric carbon dioxide. Strong inferred GrIS retreat during MIS11 relative to MIS5e suggests an indirect relationship between maximum summer temperature and cumulative interglacial mass loss, indicating strong GrIS sensitivity to duration of regional warmth and elevated atmospheric carbon dioxide.

14.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34001613

RESUMO

The Greenland Ice Sheet (GrIS) is a potentially unstable component of the Earth system and may exhibit a critical transition under ongoing global warming. Mass reductions of the GrIS have substantial impacts on global sea level and the speed of the Atlantic Meridional Overturning Circulation, due to the additional freshwater caused by increased meltwater runoff into the northern Atlantic. The stability of the GrIS depends crucially on the positive melt-elevation feedback (MEF), by which melt rates increase as the overall ice sheet height decreases under rising temperatures. Melting rates across Greenland have accelerated nonlinearly in recent decades, and models predict a critical temperature threshold beyond which the current ice sheet state is not maintainable. Here, we investigate long-term melt rate and ice sheet height reconstructions from the central-western GrIS in combination with model simulations to quantify the stability of this part of the GrIS. We reveal significant early-warning signals (EWS) indicating that the central-western GrIS is close to a critical transition. By relating the statistical EWS to underlying physical processes, our results suggest that the MEF plays a dominant role in the observed, ongoing destabilization of the central-western GrIS. Our results suggest substantial further GrIS mass loss in the near future and call for urgent, observation-constrained stability assessments of other parts of the GrIS.

15.
Scand J Prim Health Care ; : 1-7, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578458

RESUMO

INTRODUCTION: Noncommunicable diseases (NCDs) constitute a massive global burden and are the leading cause of death and disability worldwide. In Greenland, the prevalence of NCDs has historically been low. However, during the past approximately 70 years, life circumstances have changed dramatically resulting in increased life expectancy. Today, the proportion of inhabitants in Greenland ≥65 years has nearly tripled since the 1980s, and the prevalence of obesity and diabetes has increased rapidly within the past decades. The aim of this study was to describe the burden of selected NCDs in a primary care setting in Nuuk and compare it to a modern westernized suburban general practice in Denmark. METHODS: The study was performed as a cross sectional register-based study using data extracted from the electronic medical records (EMR) based on diagnosis codes from inhabitants living in Nuuk, Greenland, and a suburb in Denmark. Estimates of prevalence were age-standardized to the WHO world standard population. RESULTS: In both Nuuk and the Danish suburb, the highest prevalence was observed for hypertension (13.2% for both populations), followed by asthma (4.4 and 9.5%, respectively) and diabetes (4.3 and 2.9%, respectively). The age-standardized prevalences of diabetes, COPD, atrial fibrillation, and heart failure, were significantly higher in Nuuk, while seven NCDs including asthma, ischemic heart disease, arthritis urica, psoriasis, hyperthyreosis, hypothyreosis and osteoporosis were significantly higher in the Danish suburb. CONCLUSION: In contrast to the disease pattern observed in Greenland in the last century, the prevalence of diagnosed NCDs in Nuuk is no longer rare. Thus, the overall prevalence of NCDs in the population of Nuuk is now comparable to or even higher than in the suburb in Denmark. This calls for increased focus on all NCDs in the primary healthcare system in Greenland and adaption of the primary healthcare services to a changed disease spectrum.

16.
Nord J Psychiatry ; 78(5): 363-369, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38557415

RESUMO

INTRODUCTION: In 2016, a new addiction treatment service, Allorfik, was introduced in Greenland. Allorfik has, throughout the implementation and after, used auditing of patient records with feedback to develop the quality of care in treatment. Audits and feedback are routinely done in each treatment center. This study wishes to investigate the development of the quality of treatment through the case notes from the journal audits. METHODOLOGY: This study is based on case notes audits from 2019, 2020 and 2021. In the audits, the focus has been on the quality of documentation and content for ten specific areas in each patient record. Each area was scored on a Likert scale of 0-4 for both outcomes. Statistical analyses were done using Stata 17, and P-values < 0.05 were considered statistically significant. We present baseline characteristics for patients and illustrate the development of quality for both outcomes as time trends with scatter plots. RESULTS: The analysis was based on data from 454 patients and audits of their case notes. The mean number of weeks in treatment is 12.72, and the mean age for the people in the audited case notes is 39. Time had a positive effect on both outcomes, and so each month, documentation increased by 0.21 points (p-value = <0.001), and content increased by 0.27 points (p-value = <0.001). CONCLUSION: For documentation and content, the quality level has increased significantly with time, and the quality of case notes is at an excellent level at the final audits of all treatment centers.


Assuntos
Garantia da Qualidade dos Cuidados de Saúde , Transtornos Relacionados ao Uso de Substâncias , Humanos , Groenlândia , Adulto , Garantia da Qualidade dos Cuidados de Saúde/normas , Feminino , Transtornos Relacionados ao Uso de Substâncias/terapia , Masculino , Pessoa de Meia-Idade , Instituições de Assistência Ambulatorial/normas , Qualidade da Assistência à Saúde/normas
17.
J Ethn Subst Abuse ; : 1-16, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949863

RESUMO

In Greenland, where addiction-related concerns significantly affect well-being, research has explored alcohol's impact on health and mortality. However, no studies have focused on mortality among those who received addiction treatment. This study investigates whether individuals treated for addiction in Greenland experience elevated mortality rates compared to the general population. The study encompassed individuals receiving addiction treatment through the national system between 2012 and December 31, 2022. Data on treatment were sourced from the National Addiction Database, and Statistics Greenland. Person-years at risk were calculated and used to estimate crude mortality rates (CMRs). Adjusted standardized mortality rates (SMRs), accounting for age, sex, and calendar year, were estimated using an indirect method based on observed and expected deaths. Of the 3286 in treatment, 53.9% were women, with a median age of 37. About a third had undergone multiple treatment episodes, and 60.1% received treatment in 2019 or later. The cohort was followed for a median of 2.89 years, yielding 12,068 person-years. The overall CMR was 7.79 deaths per 1000 person-years, with a SMR of 1.42 (95% confidence interval: 1.15; 1.74). Significantly, SMRs differed by age at treatment entry, with younger groups exhibiting higher SMRs (p value = .021). This study found that individuals seeking treatment for addiction problems in Greenland had a higher mortality rate than the general population. Importantly, these SMRs were substantially lower than those observed in clinical populations in other countries.

18.
New Phytol ; 240(4): 1616-1635, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37302411

RESUMO

The determinants of biodiversity patterns can be understood using macroevolutionary analyses. The integration of fossils into phylogenies offers a deeper understanding of processes underlying biodiversity patterns in deep time. Cycadales are considered a relict of a once more diverse and globally distributed group but are restricted to low latitudes today. We still know little about their origin and geographic range evolution. Combining molecular data for extant species and leaf morphological data for extant and fossil species, we study the origin of cycad global biodiversity patterns through Bayesian total-evidence dating analyses. We assess the ancestral geographic origin and trace the historical biogeography of cycads with a time-stratified process-based model. Cycads originated in the Carboniferous on the Laurasian landmass and expanded in Gondwana in the Jurassic. Through now-vanished continental connections, Antarctica and Greenland were crucial biogeographic crossroads for cycad biogeography. Vicariance is an essential speciation mode in the deep and recent past. Their latitudinal span increased in the Jurassic and restrained toward subtropical latitudes in the Neogene in line with biogeographic inferences of high-latitude extirpations. We show the benefits of integrating fossils into phylogenies to estimate ancestral areas of origin and to study evolutionary processes explaining the global distribution of present-day relict groups.


Assuntos
Cycadopsida , Fósseis , Filogenia , Teorema de Bayes , Cycadopsida/anatomia & histologia , Biodiversidade
19.
Glob Chang Biol ; 29(19): 5582-5595, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37477068

RESUMO

Arctic food webs are being impacted by borealisation and environmental change. To quantify the impact of these multiple forcings, it is crucial to accurately determine the temporal change in key ecosystem metrics, such as trophic position of top predators. Here, we measured stable nitrogen isotopes (δ15 N) in amino acids in harp seal teeth from across the North Atlantic spanning a period of 60 years to robustly assess multi-decadal trends in harp seal trophic position, accounting for changes in δ15 N at the base of the food web. We reveal long-term variations in trophic position of harp seals which are likely to reflect fluctuations in prey availability, specifically fish- or invertebrate-dominated diets. We show that the temporal trends in harp seal trophic position differ between the Northwest Atlantic, Greenland Sea and Barents Sea, suggesting divergent changes in each local ecosystem. Our results provide invaluable data for population dynamic and ecotoxicology studies.


Assuntos
Caniformia , Focas Verdadeiras , Animais , Ecossistema , Invertebrados , Cadeia Alimentar , Biomarcadores/metabolismo
20.
Br J Nutr ; 129(5): 813-819, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-34933697

RESUMO

Greenlandic traditional nutrition was unique in the arctic environment. The aim of the present study was to reanalyse the Høygaard et al. data, focusing on two micronutrients object of discussion, i.e. Ca and vitamin C. Høygaard et al. left Copenhagen in August 1936 and stayed in East-Greenland until August 1937. The members of the expedition recorded nutritional intake whilst residing in families. However, the nutritional intake was analysed on a household level. In total, thirty-five adults and fourty-one children participated. Median total energy expenditure in kcal per d was estimated at 2978 and 2627 for male and female adults, respectively, and 1997 for children and adolescents. Median (IQR) energy consumption in kcal per d was 3881 (1568) for male and 2910 (882) for female adults. This was 2442 (857) and 2023 (1122) for male and female children and adolescents. Median (IQR) Ca intake in mg.d-1 was 555 (1110) for male and 484 (883) for female adults. This was 458 (747) and 358 (838) for male and female children and adolescents. Median (IQR) vitamin C intake in mg.d-1 was 79 (77) for male and 59 (56) for female adults. This was 44 (47) and 60 (52) for male and female children and adolescents. In this study, the importance of traditional foods in reaching an acceptable energy balance was emphasised, together with the confirmation of a low Ca intake in East-Greenland traditional dietary pattern, and the important role of algae consumption in Inuit traditional dietary pattern to avoid scurvy.


Assuntos
Dieta , Estado Nutricional , Adulto , Adolescente , Criança , Humanos , Masculino , Feminino , Vitaminas , Micronutrientes , Ácido Ascórbico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA