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Environmentally persistent free radicals (EPFRs) play an important role in aerosol effects on air quality and public health, but their atmospheric abundance and sources are poorly understood. We measured EPFRs contained in PM2.5 collected in Fairbanks, Alaska, in winter 2022. We find that EPFR concentrations were enhanced during surface-based inversion and correlate strongly with incomplete combustion markers, including carbon monoxide and elemental carbon (R2 > 0.75). EPFRs exhibit moderately good correlations with PAHs, biomass burning organic aerosols, and potassium (R2 > 0.4). We also observe strong correlations of EPFRs with hydrocarbon-like organic aerosols, Fe and Ti (R2 > 0.6), and single-particle mass spectrometry measurements reveal internal mixing of PAHs, with potassium and iron. These results suggest that residential wood burning and vehicle tailpipes are major sources of EPFRs and nontailpipe emissions, such as brake wear and road dust, may contribute to the stabilization of EPFRs. Exposure to the observed EPFR concentrations (18 ± 12 pmol m-3) would be equivalent to smoking â¼0.4-1 cigarette daily. Very strong correlations (R2 > 0.8) of EPFR with hydroxyl radical formation in surrogate lung fluid indicate that exposure to EPFRs may induce oxidative stress in the human respiratory tract.
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Contaminantes Atmosféricos , Emisiones de Vehículos , Madera , Madera/química , Alaska , Radicales Libres , Material Particulado , Monitoreo del Ambiente , Aerosoles , Hidrocarburos Policíclicos Aromáticos/análisisRESUMEN
BACKGROUND: Adverse reactions to foodstuffs (ARFS), specifically food allergy (FA) and food intolerance (FI), are increasing worldwide and represent a major public health concern. Thus, ARFS management, its identification, evaluation, and intervention, must provide a comprehensive solution. OBJECTIVES: (a) To develop a multifactorial strategy for ARFS management in adults with FA and/or FI; (b) to describe the multiple influential variables in ARFS within the realm of ARFS management; and (c) to design a personalized food allergen-specific substitutive diet (FASSD), as a 6-month dietary treatment option for adults with ARFS and as a component of ARFS management. METHODS: The ALASKA study will consider the following main variables as part of the ARFS management: (1) demographics and clinical information; (2) symptomatology, food and beverages intake and physical activity; (3) hematobiochemical study; (4) immunology; (5) enzymatic activity; (6) anthropometry, body composition, and physical fitness; (7) QoL; (8) 6-month intervention; (9) end of the study; and (10) other assessments. The FASSD will be designed with special emphasis on the commonly lacking micronutrients in the ARFS population: niacin, Mg, K, P, Ca, Zn, B12, folate, Fe, and fiber. DISCUSSION: The ALASKA study protocol has been developed as a global strategy to manage and evaluate ARFS in Spanish adults older than 18 years of age. Approaching ARFS with multiple assessments, as influencing factors, will lead to a novel strategy for ARFS management. The FASSD has been designed as a personalized tool to avoid crucial micronutrient deficiencies that a current strict food allergen avoidance or elimination diet may provoke. TRIAL REGISTRATION: The protocol has been approved by the Ethics Committee of the UPM (REF.20200602) and registered on ClinicalTrials.gov (NCT05802017).
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Alérgenos , Hipersensibilidad a los Alimentos , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Hipersensibilidad a los Alimentos/inmunología , Alérgenos/inmunología , Adulto , Alaska , Resultado del Tratamiento , Factores de Tiempo , Femenino , MasculinoRESUMEN
We estimated the annual harvest of waterfowl and Sandhill Crane Grus canadensis and their eggs by Alaska's rural residents and described seasonal and geographic patterns. Subsistence in Alaska refers to patterns of resource use typical of rural, remote regions where Indigenous people are a high proportion of the population. Rural communities in Alaska rely on the legally-allowed spring-summer harvest of migratory birds for food and socio-cultural wellbeing, in addition to harvests in the fall-winter general hunting season. We based harvest estimates on a large dataset (637 community-years) composed from multiple sources. The estimated annual average harvest of waterfowl and Sandhill Crane by rural residents was 270,641 birds/year (68% in spring-summer, 32% in fall-winter) and 36,692 eggs/year in the 2004-2015 reference period. Harvest estimates for ducks, swans, and Sandhill Crane were lower than in the 1980s-1990s. Harvest amounts, seasonality, and species composition distinguished regional patterns for the Pacific-Aleutian mainland and islands, Bering Sea mainland, St. Lawrence-Diomede islands, North Slope, and Interior Alaska-Upper Copper River. Rural residents accounted for 79% of the total waterfowl harvest in Alaska and high proportions of the total Pacific Flyway harvest for several species of sea ducks, geese, swans, and Sandhill Crane. Alaska's Indigenous people are important partners in harvest management and conservation of migratory birds. Harvest data are needed to inform efficient and appropriate decisions to achieve management goals. This study can facilitate collaboration for harvest management and conservation across Alaska and the flyways by helping diverse users to understand their contributions to the total harvest.
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Aves , Estaciones del Año , Animales , Alaska , Población Rural , Migración Animal , Humanos , Conservación de los Recursos Naturales , PatosRESUMEN
The effects of timber harvest practices and climate change have altered forest ecosystems in southeast Alaska. However, quantification of patterns and trends in stream habitats associated with these forests is limited owing to a paucity of data available in remote watersheds. Here, we analyzed a 30-year dataset from southeast Alaska's Tongass National Forest to understand how these factors shape stream habitats. First, we examined differences between broad management classes (i.e., harvested and non-harvested) that have been used to guide stream channel restoration goals. Second, we assessed associations between intrinsic landscape characteristics, watershed management, and timber harvest legacies on aquatic habitat metrics. And third, we examined trends in stream habitat metrics over the duration of the dataset to anticipate future management challenges for these systems. Small effect sizes for some harvest-related predictors suggest that some stream habitat metrics, such as pool densities, are less responsive than others, and management practices such as protecting riparian buffers as well as post-harvest restoration may help conserve fish habitats. Large wood densities increased with time since harvest at sites harvested >50 years ago, indicating that multiple decades of post-harvest forest regrowth may contribute large wood to streams (possibly alder), but that it is not enough time for old-growth trees (e.g., spruce, Picea, or hemlock, Tsuga,), classified as key wood, to develop and be delivered to streams. The declining trend in key wood (i.e., the largest size class of wood) regardless of management history may reflect that pre-harvest legacy old-growth trees are declining along streams, with low replacement. The introduction of wood to maintain complex stream habitats may fill this gap until riparian stands again contribute structural key wood to streams. Trend analyses indicate an increasing spatial extent of undercut banks that may also be influenced by shifting hydrologic regimes under climate change.
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Conservación de los Recursos Naturales , Ecosistema , Bosques , Ríos , Alaska , Cambio Climático , Agricultura Forestal , Monitoreo del Ambiente/métodosRESUMEN
Sperm whales exhibit sexual dimorphism and sex-specific latitudinal segregation. Females and their young form social groups and are usually found in temperate and tropical latitudes, while males forage at higher latitudes. Historical whaling data and rare sightings of social groups in high latitude regions of the North Pacific, such as the Gulf of Alaska (GOA) and Bering Sea/Aleutian Islands (BSAI), suggest a more complex distribution than previously understood. Sperm whales are the most sighted and recorded cetacean in marine mammal surveys in these regions but capturing their demographic composition and habitat use has proven challenging. This study detects sperm whale presence using passive acoustic data from seven sites in the GOA and BSAI from 2010 to 2019. Differences in click characteristics between males and females (i.e., inter-click and inter-pulse interval) was used as a proxy for animal size/sex to derive time series of animal detections. Generalized additive models with generalized estimation equations demonstrate how spatiotemporal patterns differ between the sexes. Social groups were present at all recording sites with the largest relative proportion at two seamount sites in the GOA and an island site in the BSAI. We found that the seasonal patterns of presence varied for the sexes and between the sites. Male presence was highest in the summer and lowest in the winter, conversely, social group peak presence was in the winter for the BSAI and in the spring for the GOA region, with the lowest presence in the summer months. This study demonstrates that social groups are not restricted to lower latitudes and capture their present-day habitat use in the North Pacific. It highlights that sperm whale distribution is more complex than accounted for in management protocol and underscores the need for improved understanding of sperm whale demographic composition to better understand the impacts of increasing anthropogenic threats, particularly climate change.
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Ecosistema , Cachalote , Animales , Cachalote/fisiología , Femenino , Masculino , Alaska , Vocalización Animal/fisiología , Estaciones del Año , Caracteres SexualesRESUMEN
In migratory animals, high mobility may reduce population structure through increased dispersal and enable adaptive responses to environmental change, whereas rigid migratory routines predict low dispersal, increased structure, and limited flexibility to respond to change. We explore the global population structure and phylogeographic history of the bar-tailed godwit, Limosa lapponica, a migratory shorebird known for making the longest non-stop flights of any landbird. Using nextRAD sequencing of 14,318 single-nucleotide polymorphisms and scenario-testing in an Approximate Bayesian Computation framework, we infer that bar-tailed godwits existed in two main lineages at the last glacial maximum, when much of their present-day breeding range persisted in a vast, unglaciated Siberian-Beringian refugium, followed by admixture of these lineages in the eastern Palearctic. Subsequently, population structure developed at both longitudinal extremes: in the east, a genetic cline exists across latitude in the Alaska breeding range of subspecies L. l. baueri; in the west, one lineage diversified into three extant subspecies L. l. lapponica, taymyrensis, and yamalensis, the former two of which migrate through previously glaciated western Europe. In the global range of this long-distance migrant, we found evidence of both (1) fidelity to rigid behavioural routines promoting fine-scale geographic population structure (in the east) and (2) flexibility to colonise recently available migratory flyways and non-breeding areas (in the west). Our results suggest that cultural traditions in highly mobile vertebrates can override the expected effects of high dispersal ability on population structure, and provide insights for the evolution and flexibility of some of the world's longest migrations.
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Migración Animal , Teorema de Bayes , Genética de Población , Filogeografía , Polimorfismo de Nucleótido Simple , Animales , Charadriiformes/genética , Charadriiformes/fisiología , Distribución Animal , AlaskaRESUMEN
Hybridization between divergent lineages can result in losses of distinct evolutionary taxa. Alternatively, hybridization can lead to increased genetic variability that may fuel local adaptation and the generation of novel traits and/or taxa. Here, we examined single-nucleotide polymorphisms generated using genotyping-by-sequencing in a population of Dolly Varden char (Pisces: Salmonidae) that is highly admixed within a contact zone between two subspecies (Salvelinus malma malma, Northern Dolly Varden [NDV] and S. m. lordi, Southern Dolly Varden [SDV]) in southwestern Alaska to assess the spatial distribution of hybrids and to test hypotheses on the origin of the admixed population. Ancestry analysis revealed that this admixed population is composed of advanced generation hybrids between NDV and SDV or advanced backcrosses to SDV; no F1 hybrids were detected. Coalescent-based demographic modelling supported the origin of this population about 55,000 years ago by secondary contact between NDV and SDV with low levels of contemporary gene flow. Ancestry in NDV and SDV varies within the watershed and ancestry in NDV was positively associated with distance upstream from the sea, contingent on habitat-type sampled, and negatively associated with the number of migrations that individual fish made to the sea. Our results suggest that divergence between subspecies over hundreds of thousands of years may not be associated with significant reproductive isolation, but that elevated diversity owing to hybridization may have contributed to adaptive divergence in habitat use and life history.
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Flujo Génico , Genética de Población , Hibridación Genética , Polimorfismo de Nucleótido Simple , Animales , Alaska , Polimorfismo de Nucleótido Simple/genética , Trucha/genética , Trucha/clasificación , GenotipoRESUMEN
Freshwater mercury (Hg) contamination is a widespread environmental concern but how proximate sources and downstream transport shape Hg spatial patterns in riverine food webs is poorly understood. We measured total Hg (THg) in slimy sculpin (Cottus cognatus) across the Kuskokwim River, a large boreal river in western Alaska and home to subsistence fishing communities which rely on fish for primary nutrition. We used spatial stream network models (SSNMs) to quantify watershed and instream conditions influencing sculpin THg. Spatial covariates for local watershed geology and slope accounted for 55 % of observed variation in sculpin THg and evidence for downstream transport of Hg in sculpins was weak. Empirical semivariograms indicated these spatial covariates accounted for most spatial autocorrelation in observed THg. Watershed geology and slope explained up to 70 % of sculpin THg variation when SSNMs accounted for instream spatial dependence. Our results provide network-wide predictions for fish tissue THg based largely on publicly available geospatial data and open-source software for SSNMs, and demonstrate how these emerging models can be used to understand contaminant behavior in spatially complex aquatic ecosystems.
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Monitoreo del Ambiente , Peces , Mercurio , Ríos , Contaminantes Químicos del Agua , Mercurio/análisis , Animales , Ríos/química , Contaminantes Químicos del Agua/análisis , Peces/metabolismo , Alaska , Cadena AlimentariaRESUMEN
We report a natural infection with a Eurasian highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus in a free-ranging juvenile polar bear (Ursus maritimus) found dead in North Slope Borough, Alaska, USA. Continued community and hunter-based participation in wildlife health surveillance is key to detecting emerging pathogens in the Arctic.
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Subtipo H5N1 del Virus de la Influenza A , Filogenia , Ursidae , Animales , Ursidae/virología , Alaska/epidemiología , Subtipo H5N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Animales Salvajes/virología , Infecciones por Orthomyxoviridae/veterinaria , Infecciones por Orthomyxoviridae/virologíaRESUMEN
The aim of this study was to investigate sleep-wake behavior and gain insights into perceived impairment (sleep, fatigue, and cognitive function) of athletes competing in two international multi-day adventure races. Twenty-four athletes took part across two independent adventure races: Queensland, Australia and Alaska, USA. Individual sleep periods were determined via actigraphy, and racers self-reported their perceived sleep disturbances, sleep impairment, fatigue and cognitive function. Each of these indices was calculated for pre-, during- and post-race periods. Sleep was severely restricted during the race period compared to pre-race (Queensland, 7:46 [0:29] vs. 2:50 [1:01]; Alaska, 7:39 [0:58] vs. 2:45 [2:05]; mean [SD], hh:mm). As a result, there was a large cumulative sleep debt at race completion, which was not 'reversed' in the post-race period (up to 1 week). The deterioration in all four self-reported scales of perceived impairment during the race period was largely restored in the post-race period. This is the first study to document objective sleep-wake behaviors and subjective impairment of adventure racers, in the context of two geographically diverse, multi-day, international adventure races. Measures of sleep deprivation indicate that sleep debt was extreme and did not recover to pre-race levels within 1 week following each race. Despite this objective debt continuing, perceived impairment returned to pre-race levels quickly post-race. Therefore, further examination of actual and perceived sleep recovery is warranted. Adventure racing presents a unique scenario to examine sleep, performance and recovery.
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Resistencia Física , Privación de Sueño , Humanos , Masculino , Adulto , Resistencia Física/fisiología , Femenino , Fatiga , Alaska , Queensland , Actigrafía , Cognición/fisiología , Adulto Joven , Sueño/fisiología , Atletas , AutoinformeRESUMEN
Alaska contains over 600 formerly used defense (FUD) sites, many of which serve as point sources of pollution. These sites are often co-located with rural communities that depend upon traditional subsistence foods, especially lipid-rich animals that bioaccumulate and biomagnify persistent organic pollutants (POPs). Many POPs are carcinogenic and endocrine-disrupting compounds that are associated with adverse health outcomes. Therefore, elevated exposure to POPs from point sources of pollution may contribute to disproportionate incidence of disease in arctic communities. We investigated PCB concentrations and the health implications of POP exposure in sentinel fishes collected near the Northeast Cape FUD site on Sivuqaq (St. Lawrence Island), Alaska. Sivuqaq residents are almost exclusively Yupik and rely on subsistence foods. At the request of the Sivuqaq community, we examined differential gene expression and developmental pathologies associated with exposure to POPs originating at the Northeast Cape FUD site. We found significantly higher levels of PCBs in Alaska blackfish (Dallia pectoralis) collected from contaminated sites downstream of the FUD site compared to fish collected from upstream reference sites. We compared transcriptomic profiles and histopathologies of these same blackfish. Blackfish from contaminated sites overexpressed genes involved in ribosomal and FoxO signaling pathways compared to blackfish from reference sites. Contaminated blackfish also had significantly fewer thyroid follicles and smaller pigmented macrophage aggregates. Conversely, we found that ninespine stickleback (Pungitius pungitius) from contaminated sites exhibited thyroid follicle hyperplasia. Despite our previous research reporting transcriptomic and endocrine differences in stickleback from contaminated vs. reference sites, we did not find significant differences in kidney or gonadal histomorphologies. Our results demonstrate that contaminants from the Northeast Cape FUD site are associated with altered gene expression and thyroid development in native fishes. These results are consistent with our prior work demonstrating disruption of the thyroid hormone axis in Sivuqaq residents.
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Monitoreo del Ambiente , Peces , Contaminantes Orgánicos Persistentes , Transcriptoma , Contaminantes Químicos del Agua , Animales , Alaska , Bifenilos Policlorados , Regiones Árticas , Especies CentinelaRESUMEN
Steller sea lions (SSL) are sentinels for monitoring environmental contaminants in remote areas of the Aleutian Islands, Alaska. Therefore, concentrations of several organochlorines (OCs) were measured in blood from 123 SSL pups sampled from 3 regions; the western Aleutian Islands (WAI), central Aleutian Islands (CAI), and the central Gulf of Alaska. Blood, blubber, and milk from 12 adult female SSL from WAI, CAI and southeast Alaska also were analyzed. Findings included the following. SSL pups had higher concentrations of some OCs and mercury (Hg) on rookeries in the WAI than those more easterly. Pups had significantly higher blood concentrations of many OC classes than adult females sampled within the same region; some pups had PCB concentrations exceeding thresholds of concern (∑PCBs >8600 ng/g lw). ∑PCB concentration in pup whole blood was positively correlated with the trophic marker, δ15N within the regions sampled, along with two PCB congeners (PCB138 and PCB153). This suggests that the dams of pups with higher ∑PCBs, PCB138, and PCB153 concentrations were feeding on more predatory prey. Adult female blubber ∑DDT and hexachlorocyclohexane concentrations were also positively correlated with δ15N values. Several pups (mostly from WAI) had blood Hg concentrations and/or blood PCB concentrations (surrogate for overall OC exposures) of concern. The finding that WAI SSL pups have been exposed to multiple contaminants calls for future investigation of their cumulative exposure to a mixture of contaminants especially their transplacental and then transmammary exposure routes.
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Monitoreo del Ambiente , Hidrocarburos Clorados , Mercurio , Leones Marinos , Contaminantes Químicos del Agua , Animales , Hidrocarburos Clorados/sangre , Mercurio/sangre , Alaska , Femenino , Contaminantes Químicos del Agua/sangre , Bifenilos Policlorados/sangreRESUMEN
Determining space use for species is fundamental to understanding their ecology, and tracking animals can reveal insights into their spatial ecology on home ranges and territories. Recent technological advances have led to GPS-tracking devices light enough for birds as small as ~30 g, creating novel opportunities to remotely monitor fine-scale movements and space use for these smaller species. We tested whether miniaturized GPS tags can allow us to understand space use of migratory birds away from their capture sites and sought to understand both pre-breeding space use as well as territory and habitat use on the breeding grounds. We used GPS tags to characterize home ranges on the breeding grounds for a migratory songbird with limited available breeding information, the Golden-crowned Sparrow (Zonotrichia atricapilla). Using GPS points from 23 individuals across 26 tags (three birds tagged twice), we found home ranges in Alaska and British Columbia were on average 44.1 ha (95% kernel density estimate). In addition, estimates of territory sizes based on field observations (mean 2.1 ha, 95% minimum convex polygon [MCP]) were three times smaller than 95% MCPs created using GPS tags (mean 6.5 ha). Home ranges included a variety of land cover classes, with shrubland particularly dominant (64-100% of home range cover for all but one bird). Three birds tracked twice returned to the same breeding area each year, supporting high breeding site fidelity for this species. We found reverse spring migration for five birds that flew up to 154 km past breeding destinations before returning. GPS-tracking technology allowed for critical ecological insights into this migratory species that breeds in very remote locations.
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Migración Animal , Sistemas de Información Geográfica , Fenómenos de Retorno al Lugar Habitual , Estaciones del Año , Gorriones , Animales , Migración Animal/fisiología , Gorriones/fisiología , Fenómenos de Retorno al Lugar Habitual/fisiología , Cruzamiento , Ecosistema , Colombia Británica , Alaska , Comportamiento de Nidificación/fisiologíaRESUMEN
In this Technical Advance, we describe a novel method to improve ecological interpretation of remotely sensed vegetation greenness measurements that involved sampling 24,395 Landsat pixels (30 m) across 639 km of Alaska's central Brooks Range. The method goes well beyond the spatial scale of traditional plot-based sampling and thereby more thoroughly relates ground-based observations to satellite measurements. Our example dataset illustrates that, along the boreal-Arctic boundary, vegetation with the greatest Landsat Normalized Difference Vegetation Index (NDVI) is taller than 1 m, woody, and deciduous; whereas vegetation with lower NDVI tends to be shorter, evergreen, or non-woody. The field methods and associated analyses advance efforts to inform satellite data with ground-based vegetation observations using field samples collected at spatial scales that closely match the resolution of remotely sensed imagery.
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Imágenes Satelitales , Tundra , Alaska , Regiones Árticas , Tecnología de Sensores Remotos/métodos , Taiga , Monitoreo del Ambiente/métodosRESUMEN
Animal-borne tags are effective instruments for collecting ocean data and can be used to fill spatial gaps in the observing network. We deployed the first conductivity, temperature, and depth (CTD) satellite tags on the dorsal fin of salmon sharks (Lamna ditropis) to demonstrate the potential of sharks to monitor essential ocean variables and oceanographic features in the Gulf of Alaska. Over 1360 km and 36 days in the summer of 2015, the salmon shark collected 56 geolocated, temperature-salinity profiles. The shark swam through a plume of anomalously salty water that originated from the "Blob" and encountered several mesoscale eddies, whose subsurface properties were altered by the marine heatwave. We demonstrate that salmon sharks have the potential to serve as submesoscale-resolving oceanographic platforms and substantially increase the spatial coverage of observations in the Gulf of Alaska.
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Tiburones , Temperatura , Animales , Océanos y Mares , Aletas de Animales , Alaska , Oceanografía/métodos , SalinidadRESUMEN
Marine Heatwaves (MHWs) can directly influence survival of marine fishes, particularly for early life stages, including age-0 juveniles during their residence in coastal nursery habitats. However, the ability of nurseries to support high fish densities, optimize foraging and growth, and protect against predators may be altered during MHWs. Gulf of Alaska Pacific cod (Gadus macrocephalus) larval, juvenile, and adult abundances declined dramatically following MHW events in 2014-2016 and 2019. To evaluate coastal nursery function during MHWs, we compared diet composition, recent growth, size, condition, and abundance of age-0 juveniles throughout their first summer before, during, and between MHWs. Diet shifted to larger prey during MHWs, particularly mysids, but diet did not appear to influence growth. We observed faster growth rates during MHWs, yet even when accounting for growth, we could not explain the higher body sizes observed in August during MHWs. Together with lower abundance and the near absence of small fish in the nursery by August during MHWs, these patterns highlight potential for size-selection and a reduced ability of nursery habitats to buffer against environmental variability during MHWs, with only a small number of large "super survivors" persisting through the summer.
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Ecosistema , Animales , Alaska , Gadiformes/fisiología , Gadiformes/crecimiento & desarrollo , Larva/fisiología , Larva/crecimiento & desarrollo , Estaciones del Año , Tamaño CorporalRESUMEN
Understanding the factors influencing species range limits is increasingly crucial in anticipating migrations due to human-caused climate change. In the boreal biome, ongoing climate change and the associated increases in the rate, size, and severity of disturbances may alter the distributions of boreal tree species. Notably, Interior Alaska lacks native pine, a biogeographical anomaly that carries implications for ecosystem structure and function. The current range of lodgepole pine (Pinus contorta var. latifolia) in the adjacent Yukon Territory may expand into Interior Alaska, particularly with human assistance. Evaluating the potential for pine expansion in Alaska requires testing constraints on range limits such as dispersal limitations, environmental tolerance limits, and positive or negative biotic interactions. In this study, we used field experiments with pine seeds and transplanted seedlings, complemented by model simulations, to assess the abiotic and biotic factors influencing lodgepole pine seedling establishment and growth after fire in Interior Alaska. We found that pine could successfully recruit, survive, grow, and reproduce across our broadly distributed network of experimental sites. Our results show that both mammalian herbivory and competition from native tree species are unlikely to constrain pine growth and that environmental conditions commonly found in Interior Alaska fall well within the tolerance limits for pine. If dispersal constraints are released, lodgepole pine could have a geographically expansive range in Alaska, and once established, its growth is sufficient to support pine-dominated stands. Given the impacts of lodgepole pine on ecosystem processes such as increases in timber production, carbon sequestration, landscape flammability, and reduced forage quality, natural or human-assisted migration of this species is likely to substantially alter responses of Alaskan forest ecosystems to climate change.
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Pinus , Pinus/fisiología , Alaska , Cambio Climático , Modelos Biológicos , Plantones , Demografía , Animales , EcosistemaRESUMEN
Pre-diabetes (pre-DM) is a strong predictor of diabetes (DM) over time. This study investigated how much of the recent increase in pre-DM identified among Alaska Native (AN) peoples living in urban southcentral Alaska may be due to changes in diagnostic methods. We used clinical and demographic data collected at baseline between 2004 and 2006 and at follow-up collected between 2015 and 2017 from the urban southcentral Alaska Education and Research Towards Health (EARTH) cohort. We used descriptive statistics and logistic regression to explore differences in demographic and clinical variables among the identified pre-DM groups. Of 388 participants in the follow-up study, 243 had A1c levels indicating pre-DM with only 20 demonstrating pre-DM also by fasting blood glucose (FBG). Current smoking was the sole predictor for pre-DM by A1c alone while abdominal obesity and elevated FBG-predicted pre-DM by A1c+FBG. No participants had an elevated FBG without an A1c elevation. A substantial portion of the rise in pre-DM found among urban southcentral AN peoples in the EARTH follow-up study was due to the addition of A1c testing. Pre-DM by A1c alone should be used to motivate behavioural changes that address modifiable risk factors, including smoking cessation, physical activity and weight management.
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Nativos Alasqueños , Estado Prediabético , Humanos , Alaska/epidemiología , Masculino , Estado Prediabético/diagnóstico , Estado Prediabético/etnología , Femenino , Persona de Mediana Edad , Adulto , Estudios de Seguimiento , Educación en Salud/organización & administración , Hemoglobina Glucada/análisis , Glucemia/análisis , Tamizaje Masivo , Anciano , Fumar/epidemiología , Fumar/etnología , Factores de RiesgoRESUMEN
OBJECTIVES: More than 3300 rural Alaska Native homes lack piped water, impeding hand hygiene. During the COVID-19 pandemic, the Alaska Native Tribal Health Consortium and the Centers for Disease Control and Prevention partnered with 10 Tribal communities and regional Tribal health organizations to install a low-cost, intermediate-technology water and sanitation system, the Miniature Portable Alternative Sanitation System (Mini-PASS). We assessed the impact of the Mini-PASS handwashing station on handwashing, other water-related uses, and problems encountered over time. METHODS: In this pre-postintervention study, we conducted semi-structured interviews by telephone seasonally with representatives of 71 households with the Mini-PASS from February 2021 through November 2022 to assess the impact of the units on water use and health. RESULTS: Before Mini-PASS installation, all participating households primarily used washbasins for handwashing. Postintervention, more than 70% of households reported using the Mini-PASS as their primary handwashing method in all 3 follow-up intervals (3, 6-9, and 12 months postintervention). The proportion of households using the handwashing station for other household tasks increased during 12 months, from 51.4% (19 of 37) at 3 months postintervention to 77.8% (21 of 27) at 12 months postintervention. Although approximately 20% to 40% of households reported problems with their handwashing station during the 12 months postintervention, a large proportion of interviewees (47% to 60%) said they were able to conduct repairs themselves. CONCLUSIONS: Households in rural Alaska quickly adopted the Mini-PASS for hand hygiene and other needs and were largely able to troubleshoot problems themselves. Further research evaluating the impact of improved handwashing behaviors facilitated by the Mini-PASS should be conducted.
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COVID-19 , Desinfección de las Manos , Higiene de las Manos , Población Rural , SARS-CoV-2 , Humanos , COVID-19/prevención & control , COVID-19/epidemiología , Desinfección de las Manos/métodos , Alaska/epidemiología , Nativos Alasqueños , Pandemias/prevención & control , Saneamiento/métodosRESUMEN
Many people with diabetes mellitus experience minimal or no complications. Our objective was to determine the proportion of Alaska Native people who experienced four major complications or mortality and to identify factors that may be associated with these outcomes. We used records in a diabetes registry and clinical and demographic variables in our analyses. We used logistic regression and Cox Proportional Hazards models to evaluate associations of these parameters with death and complications that occurred prior to 2013. The study included 591 Alaska Native people with non-type 1 diabetes mellitus, diagnosed between 1986 and 1992. Over 60% of people in this study remained free of four major diabetes-related complications for the remainder of life or throughout the approximately 20-year study period. Lower BMI, higher age at diagnosis of diabetes, and use of at least one diabetes medication were associated with death and a composite of four complications. A majority of Alaska Native people with DM had none of four major complications over a 20-year period. Lower BMI and use of diabetes medications were associated with higher hazard for some deleterious outcomes. This suggests that goals in care of elders should be carefully individualised. In addition, we discuss several programme factors that we believe contributed to favourable outcomes.