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1.
Am J Public Health ; 112(10): 1489-1497, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36103693

RESUMO

Objectives. To evaluate COVID-19 disparities among non-Hispanic American Indian/Alaska Native (AI/AN) and non-Hispanic White persons in urban areas. Methods. Using COVID-19 case surveillance data, we calculated cumulative incidence rates and risk ratios (RRs) among non-Hispanic AI/AN and non-Hispanic White persons living in select urban counties in the United States by age and sex during January 22, 2020, to October 19, 2021. We separated cases into prevaccine (January 22, 2020-April 4, 2021) and postvaccine (April 5, 2021-October 19, 2021) periods. Results. Overall in urban areas, the COVID-19 age-adjusted rate among non-Hispanic AI/AN persons (n = 47 431) was 1.66 (95% confidence interval [CI] = 1.36, 2.01) times that of non-Hispanic White persons (n = 2 301 911). The COVID-19 prevaccine age-adjusted rate was higher (8227 per 100 000; 95% CI = 6283, 10 770) than was the postvaccine rate (3703 per 100 000; 95% CI = 3235, 4240) among non-Hispanic AI/AN compared with among non-Hispanic White persons (2819 per 100 000; 95% CI = 2527, 3144; RR = 1.31; 95% CI = 1.17, 1.48). Conclusions. This study highlights disparities in COVID-19 between non-Hispanic AI/AN and non-Hispanic White persons in urban areas. These findings suggest that COVID-19 vaccination and other public health efforts among urban AI/AN communities can reduce COVID-19 disparities in urban AI/AN populations. (Am J Public Health. 2022;112(10):1489-1497. https://doi.org/10.2105/AJPH.2022.306966).


Assuntos
Nativos do Alasca , COVID-19 , Índios Norte-Americanos , Vacinas , Alaska/epidemiologia , Índios Norte-Americanos ou Nativos do Alasca , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Estados Unidos/epidemiologia
2.
Dis Aquat Organ ; 151: 29-35, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36106714

RESUMO

Cook Inlet beluga whales (CIBs) Delphinapterus leucas are Critically Endangered and genetically distinct from other beluga populations in Alaska. CIBs are exposed to numerous natural and anthropogenic sources of mortality and morbidity. This study describes congenital defects observed in 2 CIB calves. The first case, an aborted fetus, was characterized by lack of a peduncle and flukes, anorectal and genitourinary dysgenesis, and probable biliary dysplasia. The second case, a male calf, had a perineal groove defect and suspected secondary peritonitis; it also had a systemic herpesvirus infection. Further studies are needed to determine if such defects are due to genetic mutation, infectious diseases, nutritional imbalances, or contaminant exposure.


Assuntos
Beluga , Infecções por Herpesviridae , Alaska , Animais , Baías , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/veterinária , Masculino
3.
Int J Circumpolar Health ; 81(1): 2109562, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35976076

RESUMO

The second year of the COVID-19 pandemic in the Arctic was dominated by the Delta wave that primarily lasted between July and December 2021 with varied epidemiological outcomes. An analysis of the Arctic's subnational COVID-19 data revealed a massive increase in cases and deaths across all its jurisdictions but at varying time periods. However, the case fatality ratio (CFR) in most Arctic regions did not rise dramatically and was below national levels (except in Northern Russia). Based on the spatiotemporal patterns of the Delta outbreak, we identified four types of pandemic waves across Arctic regions: Tsunami (Greenland, Iceland, Faroe Islands, Northern Norway, Northern Finland, and Northern Canada), Superstorm (Alaska), Tidal wave (Northern Russia), and Protracted Wave (Northern Sweden). These regionally varied COVID-19 epidemiological dynamics are likely attributable to the inconsistency in implementing public health prevention measures, geographical isolation, and varying vaccination rates. A lesson remote and Indigenous communities can learn from the Arctic is that the three-prong (delay-prepare-respond) approach could be a tool in curtailing the impact of COVID-19 or future pandemics. This article is motivated by previous research that examined the first and second waves of the pandemic in the Arctic. Data are available at https://arctic.uni.edu/arctic-covid-19.


Assuntos
COVID-19 , Pandemias , Alaska/epidemiologia , Regiões Árticas , Groenlândia , Humanos
4.
PLoS One ; 17(8): e0273893, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36044528

RESUMO

Bering Land Bridge National Preserve and Cape Krusenstern National Monument in northwest Alaska have approximately 1600 km of predominantly soft-sediment coastlines along the Chukchi Sea, a shallow bay of the Arctic Ocean. Over the past decade, marine vessel traffic through the Bering Strait has grown exponentially to take advantage of new ice-free summer shipping routes, increasing the risk of oil spills in these fragile ecosystems. We present a high-resolution coastal vegetation map to serve as a baseline for potential spill response, restoration, and change detection. We segmented 663 km2 of high-resolution multispectral satellite images by the mean-shift method and collected 40 spectral, topographic and spatial variables per segment. The segments were classified using photo-interpreted points as training data, and verified with field based plots. Digitizing points, rather than polygons, and intersecting them with the segmentation allows for rapid collection of training data. We classified the map segments using Random Forest because of its high accuracy, computational speed, and ability to incorporate non-normal, high-dimensional data. We found creating separate classification models by each satellite scene gave highly similar results to models combining the entire study area, and that reducing the number of variables had little impact on accuracy. A unified, study area-wide Random Forest model for both parklands produced the highest accuracy of various models attempted. We mapped 18 distinct classes, with an out-of-bag error of 11.6%, resulting in an improvement to the past per-pixel classification of this coast, and in higher spatial and vegetation classification resolution. The resulting map demonstrates the utility of our point-based method and provides baseline data for incident preparedness and change detection. Elevation is highly correlated with the ordination of the vegetation types, and was the most important variable in all tested classification models. The vegetation classification brings together the largest amount of vegetation data for the Chukchi Sea coast yet documented.


Assuntos
Ecossistema , Poluição por Petróleo , Alaska , Regiões Árticas
5.
Sci Rep ; 12(1): 14260, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35995964

RESUMO

Plate corners with extreme exhumation rates are important because they offer a perspective for understanding the interactions between tectonics and surface processes. The southern Alaskan margin with its curved convergent plate boundary and associated zones of localized uplift is a prime location to study active orogeny. Here, we present the results of fully-coupled thermo-mechanical (geodynamic) and geomorphologic numerical modelling, the design of which captures the key features of the studied area: subduction of oceanic lithosphere (Pacific plate) is adjacent to a pronounced asymmetric indenter dipping at a shallow angle (Yakutat microplate), which in turn is bounded to the east by a dextral strike-slip shear zone (Fairweather fault). The resulting first-order deformation/rock uplift patterns show strong similarities with observations. In particular, relatively young thermochronological ages are reproduced along the plate-bounding (Fairweather) transform fault and in the area of its transition to convergence (the St. Elias syntaxis). The focused exhumation of the Chugach Core also finds its equivalent in model predicted zones of high rock uplift rates in an isolated region above the indenter. From these results, we suggest that the general exhumation patterns observed in southern Alaska are controlled by mutually reinforcing effects of tectonic deformation and surface erosion processes.


Assuntos
Exumação , Alaska
6.
Harmful Algae ; 117: 102270, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35944958

RESUMO

Harmful algal blooms produce biotoxins that can injure or kill fish, wildlife, and humans. These blooms occur naturally but have intensified in many locations globally due to recent climatic changes, including ocean warming. Such changes are especially pronounced in northern regions, where the effects of paralytic shellfish toxins (PSTs) on marine wildlife are of growing concern. In Alaska, seabird mortality events have increased in frequency, magnitude, and duration since 2015 alongside anomalously high ocean temperatures. Although starvation has been implicated as the apparent cause of death in many of these die-offs, saxitoxin (STX) and other PSTs have been identified as possible contributing factors. Here, we describe a mortality event at a nesting colony of Arctic Terns (Sterna paradisaea) near Juneau, Alaska in 2019 and report elevated concentrations of PSTs in bird, forage fish, and mussel samples. Concentrations of STX and other PSTs in tern tissues (2.5-51.2 µg 100g-1 STX-equivalents [STX-eq]) were of similar magnitude to those reported from other PST-induced bird die-offs. We documented high PST concentrations in blue mussels (>11,000 µg 100g-1 STX-eq; Mytilus edulis spp.) collected from nearby beaches, as well as in forage fish (up to 494 µg 100g-1 STX-eq) retrieved from Arctic Tern nests, thereby providing direct evidence of PST exposure via the terns' prey. At maximum concentrations measured in this study, a single 5 g Pacific Sand Lance (Ammodytes personatus) could exceed the median lethal STX dose (LD50) currently estimated for birds, offering strong support for PSTs as a likely source of tern mortality. In addition to describing this localized bird mortality event, we used existing energetics data from adult and nestling Arctic Terns to calculate estimated cumulative daily PST exposure based on ecologically relevant concentrations in forage fish. Our estimates revealed potentially lethal levels of PST exposure even at relatively low (≤30 ug 100g-1 STX-eq) toxin concentrations in prey. These findings suggest that PSTs present a significant hazard to Arctic Terns and other northern seabirds and should be included in future investigations of avian mortality events as well as assessments of population health.


Assuntos
Charadriiformes , Alaska , Animais , Aves , Peixes , Humanos , Saxitoxina , Alimentos Marinhos , Frutos do Mar/análise
7.
PLoS One ; 17(7): e0270474, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35881611

RESUMO

Understanding the ecological niche of some fishes is complicated by their frequent use of a broad range of food resources and habitats across space and time. Little is known about Broad Whitefish (Coregonus nasus) ecological niches in Arctic landscapes even though they are an important subsistence species for Alaska's Indigenous communities. We investigated the foraging ecology and habitat use of Broad Whitefish via stable isotope analyses of muscle and liver tissue and otoliths from mature fish migrating in the Colville River within Arctic Alaska. The range of δ13C (-31.8- -21.9‰) and δ15N (6.6-13.1‰) across tissue types and among individuals overlapped with isotope values previously observed in Arctic lakes and rivers, estuaries, and nearshore marine habitat. The large range of δ18O (4.5-10.9‰) and δD (-237.6- -158.9‰) suggests fish utilized a broad spectrum of habitats across elevational and latitudinal gradients. Cluster analysis of muscle δ13C', δ15N, δ18O, and δD indicated that Broad Whitefish occupied four different foraging niches that relied on marine and land-based (i.e., freshwater and terrestrial) food sources to varying degrees. Most individuals had isotopic signatures representative of coastal freshwater habitat (Group 3; 25%) or coastal lagoon and delta habitat (Group 1; 57%), while individuals that mainly utilized inland freshwater (Group 4; 4%) and nearshore marine habitats (Group 2; 14%) represented smaller proportions. Otolith microchemistry confirmed that individuals with more enriched muscle tissue δ13C', δD, and δ18O tended to use marine habitats, while individuals that mainly used freshwater habitats had values that were less enriched. The isotopic niches identified here represent important foraging habitats utilized by Broad Whitefish. To preserve access to these diverse habitats it will be important to limit barriers along nearshore areas and reduce impacts like roads and climate change on natural flow regimes. Maintaining these diverse connected habitats will facilitate long-term population stability, buffering populations from future environmental and anthropogenic perturbations.


Assuntos
Ecossistema , Salmonidae , Alaska , Animais , Isótopos de Carbono/análise , Lagos , Isótopos de Nitrogênio/análise , Salmonidae/fisiologia
8.
Dis Aquat Organ ; 150: 103-124, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35899963

RESUMO

A black eye syndrome (BES) was discovered in both captive and wild populations of Alaskan snow crabs Chionoecetes opilio and Tanner crabs C. bairdi. Field prevalences ranged from 0.37% (n = 594/161295) to 19.6% (n = 62/316) in snow crabs from the eastern Bering Sea and from 0.09% (n = 15/16638) to 0.7% (n = 133/18473) in Tanner crabs from the same trawl samples, with a slightly greater percentage (1.4%, n = 57/3945) in Tanner crabs from the Aleutian and Kodiak islands fisheries in the Gulf of Alaska. BES is not associated with crab mortality and has 2 distinct manifestations: abnormal black foci of internal eye pigment with no discernible histological lesions, which, in many cases, is followed by corneal shell disease with ulceration and distal eyestalk erosion. It is assumed for this study that these are early and late stages of BES that are somehow related. Our results suggest that early stages of abnormal pigmentation are noninfectious, possibly related to changing ocean conditions affecting crab endocrinology and neuropeptide control of secondary eye pigment. Potential light-induced photoreceptor damage of harvested crabs with dark-adapted eyes is another anthropogenic factor possibly contributing to the early changes in eye pigmentation. Normal eyestalk microanatomy specific for Chionoecetes spp. is provided as necessary baseline information for future studies. Early in the study, an unreported rickettsia-like organism (RLO) was discovered infecting dissected black eyestalks submitted for examination from 5 of 6 dead snow crabs, suggesting association with BES. Subsequent samples indicated the RLO was systemic, infected both black and normal-appearing eyestalks, and was unrelated to BES. However, the multiorgan infection and histopathology indicated the RLO could be a primary pathogen of snow crabs.


Assuntos
Braquiúros , Rickettsia , Alaska , Animais , Pesqueiros
9.
Nat Commun ; 13(1): 3843, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35788612

RESUMO

Arctic shrub expansion alters carbon budgets, albedo, and warming rates in high latitudes but remains challenging to predict due to unclear underlying controls. Observational studies and models typically use relationships between observed shrub presence and current environmental suitability (bioclimate and topography) to predict shrub expansion, while omitting shrub demographic processes and non-stationary response to changing climate. Here, we use high-resolution satellite imagery across Alaska and western Canada to show that observed shrub expansion has not been controlled by environmental suitability during 1984-2014, but can only be explained by considering seed dispersal and fire. These findings provide the impetus for better observations of recruitment and for incorporating currently underrepresented processes of seed dispersal and fire in land models to project shrub expansion and climate feedbacks. Integrating these dynamic processes with projected fire extent and climate, we estimate shrubs will expand into 25% of the non-shrub tundra by 2100, in contrast to 39% predicted based on increasing environmental suitability alone. Thus, using environmental suitability alone likely overestimates and misrepresents shrub expansion pattern and its associated carbon sink.


Assuntos
Incêndios , Alaska , Regiões Árticas , Mudança Climática , Tundra
10.
Artigo em Inglês | MEDLINE | ID: mdl-35881985

RESUMO

This paper presents how a community mobilization program to prevent suicide was adapted to an online format to accommodate the impossibility of in-person delivery in Alaska Native communities during the COVID-19 pandemic. The intervention, Promoting Community Conversations About Research to End Suicide (PC CARES), was created collaboratively by researchers and Alaska Native communities with the goal of bringing community members together to create research-informed and community-led suicide prevention activities in their communities. To continue our work during the COVID-19 pandemic and restrictions, we adapted the PC CARES model to a synchronous remote delivery format. This shift included moving from predominantly Alaska Native participants to one of a mainly non-Native school staff audience. This required a pivot from Alaska Native self-determination toward cultural humility and community collaboration for school-based staff, with multilevel youth suicide prevention remaining the primary aim. This reorientation can offer important insight into how to build more responsive programs for those who are not from the communities they serve. Here, we provide a narrative overview of our collaborative adaptation process, illustrated by data collected during synchronous remote facilitation of the program, and reflect on how the shift in format and audience impacted program delivery and content. The adaptation process strove to maintain the core animating features of self-determination for Alaska Native communities and people as well as the translation of scientific knowledge to practice for greater impact.


Assuntos
COVID-19 , Índios Norte-Americanos , Suicídio , Adolescente , Alaska , COVID-19/prevenção & controle , Pesquisa Participativa Baseada na Comunidade , Humanos , Pandemias , Suicídio/prevenção & controle
11.
MMWR Morb Mortal Wkly Rep ; 71(22): 730-733, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35653289

RESUMO

American Indian or Alaska Native (AI/AN) persons across the United States face substantial health disparities, including a disproportionately higher incidence of COVID-19 (1,2). AI/AN persons living in Alaska also face serious health and health care challenges, including access to care because 90% of the state's land area is inaccessible by road (3), and approximately one half of the state's AI/AN population (AI/AN race alone or in combination with another race) live in remote rural areas (4). To examine the extent of COVID-19-associated disparities among AI/AN persons living in Alaska, a retrospective analysis of COVID-19 cases reported to the Alaska Department of Health and Social Services (AKDHSS) during March 12, 2020-December 31, 2021, was conducted. The age-adjusted COVID-19 incidence among AI/AN persons was 26,583 per 100,000 standard population, approximately twice the rate among White persons living in Alaska (11,935). The age-adjusted COVID-19-associated hospitalization rate among AI/AN persons was 742 per 100,000, nearly three times the rate among White persons (273) (rate ratio [RR] = 2.72). The age-adjusted COVID-19-related mortality rate among AI/AN persons was 297 per 100,000, approximately three times that among White persons (104; RR = 2.86). Culturally competent public health efforts that are designed in collaboration with AI/AN persons and communities, including support for vaccination and other proven COVID-19 prevention strategies, are critical to reducing COVID-19-associated disparities among AI/AN persons in Alaska.


Assuntos
Nativos do Alasca , COVID-19 , Índios Norte-Americanos , Alaska/epidemiologia , Causas de Morte , Hospitalização , Humanos , Sistema de Registros , Estudos Retrospectivos , Estados Unidos/epidemiologia
12.
Parasitol Res ; 121(8): 2337-2346, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35754088

RESUMO

A new microsporidian infecting Gadus chalcogrammus Pallas, 1814 (Gadidae), is described based on morphological, ultrastructural, and molecular studies. This microsporidian parasite develops inside intramuscular spindle-shaped lesions measuring approximately 1-2 mm in width and 4-8 mm in length. Infected cells encapsulated by a host-produced wall containing a sponge-like acellular zone. Sporogony presumably proceeds via segmentation of sporogonial plasmodium, resulting in a variable number of spores. Sporogonial stages develop in sporophorous vesicles (SVs), abutting a moderately electron-dense thick walled coat of a homogeneous amorphous material. SVs space contains rare granular and tubular inclusions. Neighboring SVs often interconnected by bridges of the host cell cytoplasm that were limited by membrane comparable with SV coat. The elongate-ovoid spores, measuring 4.29 ± 0.38 × 2.51 ± 0.26 µm (N 104), possess a bipartite polaroplast and polar tube with 15-16 coils arranged in 2-3 layers. The angle of tilt of the polar tube coils is less than 30°. The sequence analysis of SSU rDNA coding region showed that the studied microsporidians differs from other fish muscle-infecting species at least in 17 bp (2.58%) and is closely related to Microsporidium cypselurus Yokoyama et al. (2002) infecting the flying fish from East China Sea. The parasite is provisionally positioned as Microsporidium theragrae sp. n.


Assuntos
Gadiformes , Microsporídios não Classificados , Microsporídios , Microsporidiose , Parasitos , Alaska , Animais , Peixes , Microsporídios não Classificados/genética , Microsporidiose/parasitologia , Filogenia
13.
Lancet Glob Health ; 10(7): e1023-e1033, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35714630

RESUMO

BACKGROUND: School-based programmes, including hearing screening, provide essential preventive services for rural children. However, minimal evidence on screening methodologies, loss to follow-up, and scarcity of specialists for subsequent care compound rural health disparities. We hypothesised telemedicine specialty referral would improve time to follow-up for school hearing screening compared with standard primary care referral. METHODS: In this cluster-randomised controlled trial conducted in 15 rural Alaskan communities, USA, we randomised communities to telemedicine specialty referral (intervention) or standard primary care referral (control) for school hearing screening. All children (K-12; aged 4-21 years) enrolled in Bering Straight School District were eligible. Community randomisation occurred within four strata using location and school size. Participants were masked to group allocation until screening day, and assessors were masked throughout data collection. Screening occurred annually, and children who screened positive for possible hearing loss or ear disease were monitored for 9 months from the screening date for follow-up. Primary outcome was the time to follow-up after a positive hearing screen; analysis was by intention to treat. The trial was registered with ClinicalTrials.gov, NCT03309553. FINDINGS: We recruited participants between Oct 10, 2017, and March 28, 2019. 15 communities were randomised: eight (750 children) to telemedicine referral and seven (731 children) to primary care referral. 790 (53·3%) of 1481 children screened positive in at least one study year: 391 (52∤1%) in the telemedicine referral communities and 399 (50∤4%) in the primary care referral communities. Of children referred, 268 (68·5%) in the telemedicine referral communities and 128 (32·1%) in primary care referral communities received follow-up within 9 months. Among children who received follow-up, mean time to follow-up was 41·5 days (SD 55·7) in the telemedicine referral communities and 92·0 days (75·8) in the primary care referral communities (adjusted event-time ratio 17·6 [95% CI 6·8-45·3] for all referred children). There were no adverse events. INTERPRETATION: Telemedicine specialty referral significantly improved the time to follow-up after hearing screening in Alaska. Telemedicine might apply to other preventive school-based services to improve access to specialty care for rural children. FUNDING: Patient-Centered Outcomes Research Institute.


Assuntos
Telemedicina , Alaska , Criança , Humanos , Encaminhamento e Consulta , População Rural , Instituições Acadêmicas
14.
PLoS One ; 17(6): e0269801, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35696414

RESUMO

The DeLong Mountain Transportation System (DMTS) haul road links the Red Dog Mine-one of the world's largest zinc mines-with a shipping port on the Chukchi Sea in northwest Alaska, USA. The road traverses 32 km of National Park Service (NPS) lands managed by Cape Krusenstern National Monument (CAKR). Fugitive dusts from ore concentrate transport and mining operations have dispersed zinc (Zn), lead (Pb), cadmium (Cd), and metal sulfides onto NPS lands since the mine began operating in 1989. This study assessed the effects of metal-enriched road dusts on the diversity and community structure of lichens, bryophytes, and vascular plants in dwarf-shrub tundra within CAKR. In a Bayesian posterior predictions model, lichen species richness (LSR) was highly correlated to distance from the haul road and was distributed on the landscape consistently with the spatial patterns of Zn, Pb and Cd patterns published earlier in this journal. The mean modeled LSR of the 3000-4000 m distance class was 41.3, and LSR decreased progressively down to 9.4 species in the 0-50 m class. An ordination of 93 lichen species by 91 plots revealed strong community patterns based on distance from the haul road. The major community gradient was highly correlated (r = 0.99) with LSR and negatively correlated with Cd, Pb and Zn (-0.79 < r < -0.74). Ordinations of bryophyte classes showed less response than lichens to distance from the road and heavy metals values, and vascular plant ordination showed less still. Measures of bryophyte health such as the midrib blackening and frond width of Hylocomium splendens were positively correlated with distance from the haul road and negatively correlated with this same suite of elements. A total area of approximately 55 km2 showed moderate to strong impacts on lichens from fugitive dusts. This is equivalent to an area of almost 1 km on both sides of the haul road running 32 km through CAKR.


Assuntos
Líquens , Metais Pesados , Poluentes do Solo , Alaska , Teorema de Bayes , Cádmio/análise , Poeira/análise , Monitoramento Ambiental , Chumbo , Metais Pesados/análise , Parques Recreativos , Poluentes do Solo/análise , Tundra , Zinco/análise
15.
Acta Biomater ; 149: 139-149, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35697199

RESUMO

Postoperative adhesion, bonding of the abdominal wall to damaged organs, causes severe complications after abdominal surgery. Despite the availability of physical barriers (i.e., solutions, films, and hydrogels), adhesion prevention materials that are a single-substance system with stability in wet tissue and ease of use have not been reported. Here, we report a microparticle based, sprayable adhesion prevention material comprising decyl group modified Alaska pollock gelatin (C10-ApGltn). C10-ApGltn microparticles (C10-MPs) were prepared by a coacervation method, freeze drying, and thermal crosslinking. The C10-MPs adhered to and formed a colloidal gel layer on intestinal serosal tissue by hydration without any crosslinking agents. After hydration of the C10-MPs, the resulting colloidal gel layer did not adhere to other tissues. Additionally, the C10-MP colloidal gel layer formed on the stomach serosal tissue showed stability when submersed in saline for 2 days. The colloidal gel layer also showed tissue followability. An in vivo rat adhesion model revealed that C10-MP colloidal gel layer on the cecum and abdominal wall defects effectively reduced postoperative adhesion and induced tissue remodeling, including re-mesothelialization. Therefore, C10-MPs are a potential anti-adhesion material for preventing postoperative adhesion. STATEMENT OF SIGNIFICANCE: We evaluated the postoperative adhesion prevention ability of a colloidal gel based on decyl group modified Alaska pollock gelatin (ApGltn) microparticles (C10-MPs). These microparticles are sprayable and form a colloidal gel with only hydration on the gastrointestinal tissue. We revealed that the modification of the decyl group into ApGltn improved the stability of C10-MP colloidal gel on the tissue by hydrophobic interaction in the in-vitro experiments. The gel prevented postoperative adhesion by being a physical barrier in the in-vivo rat adhesion model.


Assuntos
Gelatina , Adesivos Teciduais , Adesivos , Alaska , Animais , Gelatina/química , Gelatina/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Ratos , Aderências Teciduais/prevenção & controle , Adesivos Teciduais/química
16.
Environ Sci Technol ; 56(13): 9428-9434, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35736541

RESUMO

Trifluoroacetate (TFA) is a persistent perfluorinated alkanoic acid anion that has many anthropogenic sources, with fluorocarbon refrigerants being a major one. After an initial burst of research in the late 1990s and early 2000s, research on this ubiquitous pollutant declined as atmospheric emissions of the precursor compounds grew rapidly. Thus, there is little contemporaneous information about the concentrations of TFA in the environment and how they have changed over time. This research determined the change in TFA concentrations in streams by resampling a transect that was originally sampled in 1998. The transect was designed to determine the regional distribution of TFA both upwind and downwind of major metropolitan areas in Northern California as well as a set of globally remote sites in Alaska. The results showed that TFA concentrations increased by an average of 6-fold over the intervening 23 years, which resulted in a median concentration of 180 ng/L (range 21.3-2790). The highest concentrations were found in streams immediately downwind of the San Francisco Bay Area, while substantially lower concentrations were found in the upwind, regionally remote, and globally remote sites. The C3 to C5 perfluorinated alkanoic acids were also investigated, but they were rarely detected with this methodology.


Assuntos
Fluorcarbonetos , Poluentes Químicos da Água , Alaska , Monitoramento Ambiental , São Francisco , Ácido Trifluoracético/análise , Poluentes Químicos da Água/análise
17.
PLoS One ; 17(5): e0259921, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35499986

RESUMO

Conservation of Arctic fish species is challenging partly due to our limited ability to track fish through time and space, which constrains our understanding of life history diversity and lifelong habitat use. Broad Whitefish (Coregonus nasus) is an important subsistence species for Alaska's Arctic Indigenous communities, yet little is known about life history diversity, migration patterns, and freshwater habitat use. Using laser ablation Sr isotope otolith microchemistry, we analyzed Colville River Broad Whitefish 87Sr/86Sr chronologies (n = 61) to reconstruct movements and habitat use across the lives of individual fish. We found evidence of at least six life history types, including three anadromous types, one semi-anadromous type, and two nonanadromous types. Anadromous life history types comprised a large proportion of individuals sampled (collectively, 59%) and most of these (59%) migrated to sea between ages 0-2 and spent varying durations at sea. The semi-anadromous life history type comprised 28% of samples and entered marine habitat as larvae. Nonanadromous life history types comprised the remainder (collectively, 13%). Otolith 87Sr/86Sr data from juvenile and adult freshwater stages suggest that habitat use changed in association with age, seasons, and life history strategies. This information on Broad Whitefish life histories and habitat use across time and space will help managers and conservation planners better understand the risks of anthropogenic impacts and help conserve this vital subsistence resource.


Assuntos
Traços de História de Vida , Salmonidae , Alaska , Animais , Ecossistema , Isótopos de Estrôncio
18.
Sci Rep ; 12(1): 7123, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35504957

RESUMO

Beavers were not previously recognized as an Arctic species, and their engineering in the tundra is considered negligible. Recent findings suggest that beavers have moved into Arctic tundra regions and are controlling surface water dynamics, which strongly influence permafrost and landscape stability. Here we use 70 years of satellite images and aerial photography to show the scale and magnitude of northwestward beaver expansion in Alaska, indicated by the construction of over 10,000 beaver ponds in the Arctic tundra. The number of beaver ponds doubled in most areas between ~ 2003 and ~ 2017. Earlier stages of beaver engineering are evident in ~ 1980 imagery, and there is no evidence of beaver engineering in ~ 1952 imagery, consistent with observations from Indigenous communities describing the influx of beavers over the period. Rapidly expanding beaver engineering has created a tundra disturbance regime that appears to be thawing permafrost and exacerbating the effects of climate change.


Assuntos
Lagoas , Roedores , Alaska , Animais , Regiões Árticas , Tundra
19.
Environ Sci Technol ; 56(12): 7657-7667, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35544773

RESUMO

Fairbanks, Alaska, is a subarctic city with fine particle (PM2.5) concentrations that exceed air quality regulations in winter due to weak dispersion caused by strong atmospheric inversions, local emissions, and the unique chemistry occurring under the cold and dark conditions. Here, we report on observations from the winters of 2020 and 2021, motivated by our pilot study that showed exceptionally high concentrations of fine particle hydroxymethanesulfonate (HMS) or related sulfur(IV) species (e.g., sulfite and bisulfite). We deployed online particle-into-liquid sampler-ion chromatography (PILS-IC) in conjunction with a suite of instruments to determine HMS precursors (HCHO, SO2) and aerosol composition in general, with the goal to characterize the sources and sinks of HMS in wintertime Fairbanks. PM2.5 HMS comprised a significant fraction of PM2.5 sulfur (26-41%) and overall PM2.5 mass concentration of 2.8-6.8% during pollution episodes, substantially higher than what has been observed in other regions, likely due to the exceptionally low temperatures. HMS peaked in January, with lower concentrations in December and February, resulting from changes in precursors and meteorological conditions. Strong correlations with inorganic sulfate and organic mass during pollution events suggest that HMS is linked to processes responsible for poor air quality episodes. These findings demonstrate unique aspects of air pollution formation in cold and humid atmospheres.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aerossóis/química , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Alaska , Monitoramento Ambiental/métodos , Material Particulado/análise , Projetos Piloto , Estações do Ano , Enxofre
20.
J Community Health ; 47(4): 680-686, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35567711

RESUMO

Understanding changes in substance use in a small population state is challenging. Many national datasets restrict data to reduce the probability of identifying persons. Alaska is a small population state (731,000 residents) with a large geographic region (25% the size of the lower 48), a diverse population, and highly variable seasons, with fewer than 10% of the state being road accessible. Given the uniqueness of Alaska, this project sought to understand what could be learned about addiction and its relationships with unemployment and median income in Alaska. National Survey on Drug Use and Health, State and Small Area Estimates (1999-2020) data were analyzed to measure prevalence changes. Outcome prevalence were independently correlated with median income and annual unemployment rate as the annual collection periods varied. Analyses were limited to simple bivariate analyses due to the data restrictions. Median income was found to have stronger correlational relationships and significant relationships with more negative outcomes compared to unemployment. While annual unemployment rates had statistically significant relationships with substance use outcomes, negative mental health outcomes appeared more related to unemployment than median income. Alcohol use in the past month, cigarette and tobacco use, and pain reliever misuse declined while binge drinking in the past month and illicit drug use increased. More people reported depression, serious mental illness, and suicidal ideation and planning over time peaking in the last year of data collection. While NSDUH data provide some idea of the changes in drug use over time, their effectiveness in Alaska is unknown. Many data sources claim they are nationally representative, but these statements cannot be objectively measured. We will use these outcomes and data as a baseline for future studies where we will explore state specific data sources.


Assuntos
Transtornos Relacionados ao Uso de Substâncias , Alaska/epidemiologia , Humanos , Prevalência , População Rural , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Desemprego
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