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1.
MMWR Morb Mortal Wkly Rep ; 70(16): 583-588, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33886533

RESUMO

Travel can facilitate SARS-CoV-2 introduction. To reduce introduction of SARS-CoV-2 infections, the state of Alaska implemented a program on June 6, 2020, for arriving air, sea, and road travelers that required either molecular testing for SARS-CoV-2, the virus that causes COVID-19, or a 14-day self-quarantine after arrival. The Alaska Department of Health and Social Services (DHSS) used weekly standardized reports submitted by 10 participating Alaska airports to evaluate air traveler choices to undergo testing or self-quarantine, traveler test results, and airport personnel experiences while implementing the program. Among 386,435 air travelers who arrived in Alaska during June 6-November 14, 2020, a total of 184,438 (48%) chose to be tested within 72 hours before arrival, 111,370 (29%) chose to be tested on arrival, and 39,685 (10%) chose to self-quarantine without testing after arrival. An additional 15,112 persons received testing at airport testing sites; these were primarily travelers obtaining a second test 7-14 days after arrival, per state guidance. Of the 126,482 airport tests performed in Alaska, 951 (0.8%) results were positive, or one per 406 arriving travelers. Airport testing program administrators reported that clear communication, preparation, and organization were vital for operational success; challenges included managing travelers' expectations and ensuring that sufficient personnel and physical space were available to conduct testing. Expected mitigation measures such as vaccination, physical distancing, mask wearing, and avoidance of gatherings after arrival might also help limit postarrival transmission. Posttravel self-quarantine and testing programs might reduce travel-associated SARS-CoV-2 transmission and importation, even without enforcement. Traveler education and community and industry partnerships might help ensure success.


Assuntos
Aeroportos , Viagem/legislação & jurisprudência , Alaska/epidemiologia , Humanos , Avaliação de Programas e Projetos de Saúde , Quarentena , Doença Relacionada a Viagens
2.
MMWR Morb Mortal Wkly Rep ; 70(17): 622-626, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33914728

RESUMO

Large COVID-19 outbreaks have occurred in high-density workplaces, such as food processing facilities (1). Alaska's seafood processing industry attracts approximately 18,000 out-of-state workers annually (2). Many of the state's seafood processing facilities are located in remote areas with limited health care capacity. On March 23, 2020, the governor of Alaska issued a COVID-19 health mandate (HM10) to address health concerns related to the impending influx of workers amid the COVID-19 pandemic (3). HM10 required employers bringing critical infrastructure (essential) workers into Alaska to submit a Community Workforce Protective Plan.* On May 15, 2020, Appendix 1 was added to the mandate, which outlined specific requirements for seafood processors, to reduce the risk for transmission of SARS-CoV-2, the virus that causes COVID-19, in these high-density workplaces (4). These requirements included measures to prevent introduction of SARS-CoV-2 into the workplace, including testing of incoming workers and a 14-day entry quarantine before workers could enter nonquarantine residences. After 13 COVID-19 outbreaks in Alaska seafood processing facilities and on processing vessels during summer and early fall 2020, State of Alaska personnel and CDC field assignees reviewed the state's seafood processing-associated cases. Requirements were amended in November 2020 to address gaps in COVID-19 prevention. These revised requirements included restricting quarantine groups to ≤10 persons, pretransfer testing, and serial testing (5). Vaccination of this essential workforce is important (6); until high vaccination coverage rates are achieved, other mitigation strategies are needed in this high-risk setting. Updating industry guidance will be important as more information becomes available.


Assuntos
/epidemiologia , Surtos de Doenças , Indústria de Processamento de Alimentos , Doenças Profissionais/epidemiologia , Alaska/epidemiologia , Humanos , Doenças Profissionais/prevenção & controle
3.
Mar Pollut Bull ; 166: 112183, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33647846

RESUMO

Southeast Alaska sea otters (Enhydra lutris) have had a rapid rise in their population. As they feed primarily on sessile prey, they are excellent sentinels for examining metals contamination. Objectives of this study on sea otters were to determine: (1) concentrations of metals in different tissues; (2) whether metals biomagnify from stomach contents (i.e., the prey) to other tissues; (3) whether selenium and mercury concentrations indicate an overall health benefit or risk; and (4) if metals concentrations in tissues vary with body size. Brain, kidney, gonad, liver, and stomach contents were collected from freshly harvested sea otters in Icy Strait, Alaska, and analyzed for arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), total mercury (THg), and selenium (Se). Metals concentrations varied significantly, and some were biomagnified, with livers and kidneys harboring the highest concentrations. Lead and arsenic appeared to be readily excreted. This study represents baseline metals concentrations to assist in monitoring the health of sea otters.


Assuntos
Lontras , Alaska , Animais , Encéfalo , Conteúdo Gastrointestinal , Gônadas , Rim , Fígado
4.
Environ Sci Technol ; 55(8): 4974-4983, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33724011

RESUMO

The direct and indirect photochemical degradation of rotenone (ROT) and deguelin (DEG), the primary reduced nicotinamide adenine dinucleotide-inhibiting rotenoid components of the piscicide CFT Legumine, were investigated under simulated sunlight conditions relevant to their dissipation from high-latitude surface waters. Photochemical degradation dominated the elimination of ROT and DEG from surface waters with half-lives ranging from 1.17 to 2.32 and 4.18 to 20.12 h for DEG and ROT, respectively, when the rotenoids were applied in the formulation CFT Legumine. We assessed enhanced degradation processes using argon-purged and cesium chloride-amended water, which demonstrated the rotenoids to rapidly decompose from excited triplet states. We further assessed the influence of reactive oxygen species by hydroxyl radical quenching and thermal generation of singlet oxygen. The studied reactive oxygen species did not significantly contribute; however, alcohols such as isopropanol may inhibit degradation by quenching ROT excited states or preventing intersystem crossing. Finally, we compared photochemical degradation in water collected from Hope Lake, Alaska, to a solution of Suwanee River fulvic acids, which demonstrated that dissolved organic matter (DOM) quality is a major factor that modulates ROT attenuation through a combination of shielding (light attenuation) and excited-state quenching mechanisms and is temperature-dependent. Molecular-level characterizations of DOM may help account for the site-specific degradation of these rotenoids in the environment.


Assuntos
Lagos , Poluentes Químicos da Água , Alaska , Radical Hidroxila , Processos Fotoquímicos , Fotólise , Rotenona/análogos & derivados
5.
Am J Bot ; 108(3): 495-504, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33650114

RESUMO

PREMISE: Mosses are a major component of Arctic vegetation today, with >500 species known to date. However, the origins of the Arctic moss flora are poorly documented in the fossil record, especially prior to the Pliocene. Here, we present the first anatomically preserved pre-Cenozoic Arctic moss and discuss how the unique biology of bryophytes has facilitated their success in polar environments over geologic time. METHODS: A permineralized fossil moss gametophyte within a block of Late Cretaceous terrestrial limestone, collected along the Colville River on the North Slope of Alaska, was studied in serial sections prepared using the cellulose acetate peel technique. RESULTS: The moss gametophyte is branched and has leaves with a broad base, narrow blade, and excurrent costa. We describe this fossil as Cynodontium luthii sp. nov., an extinct species of a genus that is known from the High Arctic today. Cynodontium luthii is the oldest evidence of the family Rhabdoweisiaceae (by ≥18 Ma) and reveals that genera of haplolepideous mosses known in the extant Arctic flora also lived in high-latitude temperate deciduous forests during the Late Cretaceous. CONCLUSIONS: The occurrence of C. luthii in Cretaceous sediments, together with a rich Pliocene-to-Holocene fossil record of extant moss genera in the High Arctic, suggests that some moss lineages have exploited their poikilohydric, cold- and desiccation-tolerant physiology to live in the region when it experienced both temperate and freezing climates.


Assuntos
Briófitas , Bryopsida , Alaska , Fósseis , Células Germinativas Vegetais
6.
Sci Total Environ ; 772: 145386, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33770858

RESUMO

Soil organic matter (SOM) is related to vegetation, soil bacteria, and soil properties; however, not many studies link all these parameters simultaneously, particularly in tundra ecosystems vulnerable to climate change. Our aim was to describe the relationships between vegetation, bacteria, soil properties, and SOM composition in moist acidic tundra by integrating physical, chemical, and molecular methods. A total of 70 soil samples were collected at two different depths from 36 spots systematically arranged over an area of about 300 m × 50 m. Pyrolysis-gas chromatography/mass spectrometry and pyrosequencing of the 16S rRNA gene were used to identify the molecular compositions of the SOM and bacterial community, respectively. Vegetation and soil physicochemical properties were also measured. The sampling sites were grouped into three, based on their SOM compositions: Sphagnum moss-derived SOM, lipid-rich materials, and aromatic-rich materials. Our results show that SOM composition is spatially structured and linked to microtopography; however, the vegetation, soil properties, and bacterial community composition did not show overall spatial structuring. Simultaneously, soil properties and bacterial community composition were the main factors explaining SOM compositional variation, while vegetation had a residual effect. Verrucomicrobia and Acidobacteria were related to polysaccharides, and Chloroflexi was linked to aromatic compounds. These relationships were consistent across different hierarchical levels. Our results suggest that SOM composition at a local scale is closely linked with soil factors and the bacterial community. Comprehensive observation of ecosystem components is recommended to understand the in-situ function of bacteria and the fate of SOM in the moist acidic tundra.


Assuntos
Ecossistema , Solo , Alaska , Bactérias/genética , RNA Ribossômico 16S/genética , Microbiologia do Solo , Tundra
8.
Glob Chang Biol ; 27(9): 1859-1878, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33577102

RESUMO

During the Pacific marine heatwave of 2014-2016, abundance and quality of several key forage fish species in the Gulf of Alaska were simultaneously reduced throughout the system. Capelin (Mallotus catervarius), sand lance (Ammodytes personatus), and herring (Clupea pallasii) populations were at historically low levels, and within this community abrupt declines in portfolio effects identify trophic instability at the onset of the heatwave. Although compensatory changes in age structure, size, growth or energy content of forage fish were observed to varying degrees among all these forage fish, none were able to fully mitigate adverse impacts of the heatwave, which likely included both top-down and bottom-up forcing. Notably, changes to the demographic structure of forage fish suggested size-selective removals typical of top-down regulation. At the same time, changes in zooplankton communities may have driven bottom-up regulation as copepod community structure shifted toward smaller, warm water species, and euphausiid biomass was reduced owing to the loss of cold-water species. Mediated by these impacts on the forage fish community, an unprecedented disruption of the normal pelagic food web was signaled by higher trophic level disruptions during 2015-2016, when seabirds, marine mammals, and groundfish experienced shifts in distribution, mass mortalities, and reproductive failures. Unlike decadal-scale variability underlying ecosystem regime shifts, the heatwave appeared to temporarily overwhelm the ability of the forage fish community to buffer against changes imposed by warm water anomalies, thereby eliminating any ecological advantages that may have accrued from having a suite of coexisting forage species with differing life-history compensations.


Assuntos
Ecossistema , Peixes , Alaska , Animais , Cadeia Alimentar , Zooplâncton
9.
J Cross Cult Gerontol ; 36(1): 43-67, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33566251

RESUMO

The population of the United States is aging and by 2045 it is projected that approximately 1 in every 6 Alaskans will be 65+. Delivering healthcare and meeting the needs of older Alaskans in their community is critical to supporting healthy aging and community sustainability. Alaska Native (AN) Elders are underserved with very few studies providing an emic perspective on their experience aging. This research opens the door and allows us a glimpse of the AN Elder experience of aging: the values, beliefs, and behaviors that allow them to age well. This study highlights the characteristics and activities of AN Elders in the Aleutian and Pribilof Islands to further develop the model of AN successful aging. There are many theories of aging and this study explores a cross-cultural understanding of gerotranscendence - the personal and interpersonal changes that result from successful aging or achieving Eldership. This study interviewed Elders in two communities of the Aleutian and Pribilof Islands region. Using 22 standardized questions based on the explanatory model, researchers facilitated discussion of what it means to be an Elder and age successfully. Employing thematic analysis, interview transcripts were analyzed for themes to organize the data. Themes were organized into 5 core elements of successful aging with specific emphasis on values, beliefs, and behaviors that were protective and helped them adapt to aging-related changes. Interview content, meaning, and themes support the four elements of the AN model of successful aging developed by Lewis (The Gerontologist, 51(4), 540-549, 2011): Mental and Emotional Wellbeing, Spirituality, Purposefulness and Engagement, and Physical Health. Elders' stories highlight the importance of reflection, personal growth, and psychosocial development. Elders who more strongly identified with their role in the community described how their perspective had changed and they shared stories that emphasized culture, connection to the land, and enjoyment of daily activities that resulted in increased life satisfaction. Elders provided clear evidence that they experienced aspects of gerotranscendence, which Tornstam (Journal of Aging Studies, 11(2), 143-154, 1997) categorized as the cosmic dimension, the self, and social and personal relationships. Elders adapting to aging-related changes and embracing their role as an Elder provided the greatest evidence of gerotranscendence - they developed new perspectives on life, took on new roles within the community, and experienced a shift in mindset that reinforced the importance of culture, tradition, and the Native Way of Life. This research allowed AN Elders to share their experiences, define successful aging, and expand the concept of Eldership to include changes in mindset, values, and relationships with themselves and others. The study is a framework to help us better understand the experiences of AN Elders aging successfully and the wisdom they wish to impart to others to help them learn to live healthy and meaningful lives.


Assuntos
Envelhecimento/psicologia , Envelhecimento Saudável , Satisfação Pessoal , Qualidade de Vida , Espiritualidade , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Alaska , Cultura , Feminino , Nível de Saúde , Humanos , Masculino , Saúde Mental , Pesquisa Qualitativa , Religião e Psicologia
10.
Sci Total Environ ; 775: 144894, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-33631572

RESUMO

The Steller sea lion (SSL) population west of 144°W longitude experienced a significant population decline. While there appears to be a stable or increasing population trend in rookeries in the Gulf of Alaska (GOA) and Southeast Alaska (SEA), some rookeries within the Aleutian Islands (AI) have failed to recover. Previous studies found regional differences in whole blood total mercury concentrations ([THg]) showing more than 20% of AI pups had [THg] above critical thresholds for increased risk of immunological effects and other adverse outcomes. Measurements of immune cell-signaling proteins can be used to evaluate the immune status of marine mammals in relation to [THg]. We compared serum cytokine and chemokine concentrations in pups among regions (AI, eastern GOA, SEA), and examined associations among cytokines, chemokines, white blood cell (WBC) counts, and [THg]. Considering liver is an important target organ for mercury and immune protein synthesis we additionally examined the relationship of [THg] with liver-related enzymes serum aspartate (AST) and alanine aminotransferase (ALT). We observed regional differences in cytokine and chemokine measurements and immune protein associations. There was a positive association between total WBC counts and [THg] in AI pups, whereas a negative association between lymphocytes and [THg] in SEA pups. These findings may indicate regional variation in proliferation and differentiation of hematopoietic cells, differences in immune system development, and/or a difference in antigenic stimuli. No associations between [THg] and cytokines, chemokines, AST or ALT were found. Observed regional differences in cytokine and chemokine milieu during gestational and early development in SSL pups could lead to an imbalance in cell differentiation that could impact immunological resiliency in juvenile and adult life stages. We report concentration ranges of a suite of cytokines and chemokines which may prove to be a useful metric for ecotoxicology and risk assessment studies in SSLs and other wildlife.


Assuntos
Mercúrio , Leões-Marinhos , Alaska , Animais , Citocinas , Contagem de Leucócitos , Mercúrio/análise
11.
JAMA Netw Open ; 4(2): e210138, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33630088

RESUMO

Importance: Recent studies have revealed increases in population-level cannabis use after legalization of recreational cannabis. However, the association of cannabis legalization with maternal cannabis use during important life stages remains unknown. Objective: To investigate the association of legalization of recreational cannabis with maternal cannabis use during the preconception, prenatal, and postpartum periods. Design, Setting, and Participants: This repeated cross-sectional study used state-level data on women who delivered live-born infants in the US from the Pregnancy Risk Assessment Monitoring System from January 2004 to December 2018. Data from 2 states that had legalized recreational cannabis (Alaska and Maine) and 2 states that had not legalized recreational cannabis (New Hampshire and Vermont) were used. Women completed surveys 2 to 6 months after delivery, reporting preconception, prenatal, and postpartum cannabis use. Exposure: State recreational cannabis legalization. Main Outcomes and Measures: The 3 primary outcomes were self-reported cannabis use during the 12 months before pregnancy (preconception), during pregnancy (prenatal), and the 2 to 6 months after pregnancy (postpartum). A difference-in-differences analysis was used to compare changes in the prevalence of maternal cannabis use during each period before and after state legalization of recreational cannabis, controlling for maternal characteristics (age, race/ethnicity, educational level, income, cigarette smoking, and breastfeeding) and state fixed effects. State-specific survey weights were used. Results: The analytic sample included 23 082 women in the preconception period, 23 859 in the prenatal period, and 26 610 in the postpartum period. In each analysis, most women were married (range among all groups, 63.9%-64.8%), aged 25 to 34 years (preconception, 55.4%; prenatal, 55.9%; postpartum, 56.1%), and had an annual household income less than $50 000 (preconception, 55.7%; prenatal, 56.3%; postpartum, 55.5%). In adjusted analyses, preconception and postpartum cannabis use increased significantly in states that had legalized recreational cannabis compared with states that had not legalized it (preconception risk difference, 0.0457 [95% CI, 0.0013-0.0900]; P = .04; postpartum risk difference, 0.0539 [95% CI, 0.0259-0.0818]; P < .001). The risk difference for prenatal cannabis use was not significant (0.0070; 95% CI, -0.0120 to 0.0260; P = .47). Conclusions and Relevance: In this repeated cross-sectional study, recreational cannabis legalization was associated with changes in maternal cannabis use before and after pregnancy. The findings suggest that future studies should undertake an interdisciplinary approach to maximize benefit and application of findings to future public health, health care, and policy sectors.


Assuntos
Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , Uso da Maconha/epidemiologia , Período Pós-Parto , Gravidez , Adolescente , Adulto , Alaska/epidemiologia , Estudos Transversais , Feminino , Humanos , Maine/epidemiologia , Uso da Maconha/legislação & jurisprudência , New Hampshire/epidemiologia , Prevalência , Vermont/epidemiologia , Adulto Jovem
12.
Dis Aquat Organ ; 143: 69-78, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33570041

RESUMO

Streptococcus lutetiensis and S. phocae have been associated with significant morbidity and mortality in northern sea otters Enhydra lutris kenyoni in Alaska, USA, but the route and mechanism(s) of transmission remain unknown. The goal of this study was to determine the competence of common northern sea otter prey to harbor 2 species of pathogenic Streptococcus bacteria. Prey items (bay mussels Mytilus trossulus, butter clams Saxidomus giganteus, Dungeness crab Metacarcinus magister and black turban snails Tegula funebralis) were exposed to known concentrations of exponential phase cultures of S. lutetiensis and S. phocae in seawater for 24 h. A quantitative PCR assay was developed targeting the sodA gene of both S. lutetiensis and S. phocae to quantify DNA in the prey samples. Results (mean ± SD) revealed that butter clams had the highest concentration of bacteria (4.32 × 107 ± 8.20 × 106 CFU ml-1 of S. lutetiensis, 1.20 × 108 ± 2.08 × 107 CFU ml-1 of S. phocae), followed by mussels (4.26 × 107 ± 1.66 × 107 CFU ml-1, 1.16 × 108 ± 5.39 × 107 CFU ml-1), snails (1.90 × 107 ± 5.26 × 106 CFU ml-1, 5.97 × 107 ± 2.07 × 107 CFU ml-1) and crab (1.46 × 107 ± 0 CFU ml-1, 1.64 × 107 ± 0 CFU ml-1). All prey species harbored higher concentrations of S. phocae than S. lutetiensis.


Assuntos
Lontras , Alaska , Animais , Streptococcus
13.
Microbiome ; 9(1): 53, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33622403

RESUMO

BACKGROUND: Mosses in high-latitude ecosystems harbor diverse bacterial taxa, including N2-fixers which are key contributors to nitrogen dynamics in these systems. Yet the relative importance of moss host species, and environmental factors, in structuring these microbial communities and their N2-fixing potential remains unclear. We studied 26 boreal and tundra moss species across 24 sites in Alaska, USA, from 61 to 69° N. We used cultivation-independent approaches to characterize the variation in moss-associated bacterial communities as a function of host species identity and site characteristics. We also measured N2-fixation rates via 15N2 isotopic enrichment and identified potential N2-fixing bacteria using available literature and genomic information. RESULTS: Host species identity and host evolutionary history were both highly predictive of moss microbiome composition, highlighting strong phylogenetic coherence in these microbial communities. Although less important, light availability and temperature also influenced composition of the moss microbiome. Finally, we identified putative N2-fixing bacteria specific to some moss hosts, including potential N2-fixing bacteria outside well-studied cyanobacterial clades. CONCLUSIONS: The strong effect of host identity on moss-associated bacterial communities demonstrates mosses' utility for understanding plant-microbe interactions in non-leguminous systems. Our work also highlights the likely importance of novel bacterial taxa to N2-fixation in high-latitude ecosystems. Video Abstract.


Assuntos
Briófitas/microbiologia , Fixação de Nitrogênio , Bactérias Fixadoras de Nitrogênio/classificação , Bactérias Fixadoras de Nitrogênio/metabolismo , Alaska , Filogenia
14.
Science ; 371(6524): 13, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33384358
15.
Glob Chang Biol ; 27(7): 1408-1430, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33394532

RESUMO

Climate change is creating widespread ecosystem disturbance across the permafrost zone, including a rapid increase in the extent and severity of tundra wildfire. The expansion of this previously rare disturbance has unknown consequences for lateral nutrient flux from terrestrial to aquatic environments. Lateral loss of nutrients could reduce carbon uptake and slow recovery of already nutrient-limited tundra ecosystems. To investigate the effects of tundra wildfire on lateral nutrient export, we analyzed water chemistry in and around the 10-year-old  Anaktuvuk River fire scar in northern Alaska. We collected water samples from 21 burned and 21 unburned watersheds during snowmelt, at peak growing season, and after plant senescence in 2017 and 2018. After a decade of ecosystem recovery, aboveground biomass had recovered in burned watersheds, but overall carbon and nitrogen remained ~20% lower, and the active layer remained ~10% deeper. Despite lower organic matter stocks, dissolved organic nutrients were substantially elevated in burned watersheds, with higher flow-weighted concentrations of organic carbon (25% higher), organic nitrogen (59% higher), organic phosphorus (65% higher), and organic sulfur (47% higher). Geochemical proxies indicated greater interaction with mineral soils in watersheds with surface subsidence, but optical analysis and isotopes suggested that recent plant growth, not mineral soil, was the main source of organic nutrients in burned watersheds. Burned and unburned watersheds had similar δ15 N-NO3 - , indicating that exported nitrogen was of preburn origin (i.e., not recently fixed). Lateral nitrogen flux from burned watersheds was 2- to 10-fold higher than rates of background nitrogen fixation and atmospheric deposition estimated in this area. These findings indicate that wildfire in Arctic tundra can destabilize nitrogen, phosphorus, and sulfur previously stored in permafrost via plant uptake and leaching. This plant-mediated nutrient loss could exacerbate terrestrial nutrient limitation after disturbance or serve as an important nutrient release mechanism during succession.


Assuntos
Ecossistema , Incêndios Florestais , Alaska , Regiões Árticas , Nutrientes , Solo , Tundra
17.
PLoS One ; 16(1): e0245213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33439906

RESUMO

Improving our knowledge of subsistence strategies and food processing techniques of past societies is of prime interest for better understanding human cultures as well as multiple aspects of human evolution. Beyond the simple matter of food itself, a substantial portion of socio-economic behavior is expressed in what, how, when, and with whom we eat. Over the last few decades, diverse methodologies for the analysis and interpretation of cut marks have progressively provided new insights for past butchery practices. For example, a recent study of the production of antelope biltong in South Africa concluded that the drying of meat generates high frequencies of longitudinal cut marks. This paper presents a cut mark analysis of faunal remains recovered by Lewis Binford from 8 campsites occupied by Nunamiut groups from the end of 19th to middle of the 20th century in the area around Anaktuvuk Pass, Alaska. The preparation of meat-primarily from caribou (Rangifer tarandus)-varied at these sites according to the season of occupation and was, depending on the site, either immediately consumed, processed after being stored in ice-cellars, or dried and stored. These faunal assemblages therefore provide a unique opportunity to explore the material traces of different meat preparation and preservation techniques in order to identify whether specific patterns can be identified and subsequently used to explore subsistence practices in the past. Binford's Nunamiut faunal assemblages, which were produced by individuals using traditional techniques and methods, were analyzed in order to 1) further test the hypothesis that meat drying produces high frequencies of longitudinal cut marks, 2) explore the common assumption that skilled butchers leave smaller numbers of cut marks on bones compared to less experienced individuals, and 3) test whether cut mark patterns vary as a function of the processing techniques employed. The introduction of a %cutL index represents a quicker alternative to geo-referencing cut marks on bones when exploring meat processing techniques and methods and can easily be integrated in zooarchaeological analyses. While the results obtained support processing techniques linked to meat drying to leave high numbers of longitudinal cut marks, they are inconsistent with cut mark frequencies varying as a function of the butcher's skill and experience. Analyzing cut mark patterns is therefore a reliable means for exploring food processing by past human societies and, by extension, their methods for safeguarding against unfavorable seasonal variations in both the abundance and condition of prey species. Identifying food storage in the archaeological record equally provides a unique window on to the social dynamics and potential inequalities of past societies.


Assuntos
Arqueologia , Manipulação de Alimentos , Carne , Alaska , Humanos
18.
PLoS One ; 16(1): e0244960, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33481844

RESUMO

Spatial structuring of mid-trophic level forage communities in the Gulf of Alaska (GoA) is poorly understood, even though it has clear implications for the health of fisheries and marine wildlife populations. Here, we test the hypothesis that summertime (May-August) mesozooplankton communities are spatially-persistent across years of varying ocean conditions, including during the marine heatwave of 2014-2016. We use spatial ordinations and hierarchical clustering of Continuous Plankton Recorder (CPR) sampling over 17 years (2000-2016) to (1) characterize typical zooplankton communities in different regions of the GoA, and (2) investigate spatial structuring relative to variation in ocean temperatures and circulation. Five regional communities were identified, each representing distinct variation in the abundance of 18 primary zooplankton taxa: a distinct cluster of coastal taxa on the continental shelf north of Vancouver Island; a second cluster in the western GoA associated with strong currents and cold water east of Unimak Pass; a shelf break cluster rich in euphausiids found at both the eastern and western margins of the GoA; a broad offshore cluster of abundant pelagic zooplankton in the southern GoA gyre associated with stable temperature and current conditions; and a final offshore cluster exhibiting low zooplankton abundance concentrated along the northeastern arm of the subarctic gyre where ocean conditions are dominated by eddy activity. When comparing years of anomalous warm and cold sea surface temperatures, we observed change in the spatial structure in coastal communities, but little change (i.e., spatial persistence) in the northwestern GoA basin. Whereas previous studies have shown within-region variability in zooplankton communities in response to ocean climate, we highlight both consistency and change in regional communities, with interannual variability in shelf communities and persistence in community structure offshore. These results suggest greater variability in coastal food webs than in the central portion of the GoA, which may be important to energy exchange from lower to upper trophic levels in the mesoscale biomes of this ecosystem.


Assuntos
Zooplâncton , Alaska , Animais , Ecossistema , Oceano Pacífico , Análise Espaço-Temporal , Zooplâncton/fisiologia
19.
Int J Biol Macromol ; 172: 580-588, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33476616

RESUMO

Tissue adhesives have been developed for sealing tissue damaged in surgery. Among these, sheet-type adhesives require a relatively long time to adhere to biological tissue under wet conditions. To address this clinical problem, we fabricated a tissue-adhesive fiber sheet (AdFS) based on decanyl group (C10) modified Alaska pollock-derived gelatin (C10-ApGltn) using electrospinning. Ultraviolet (UV) irradiation of the AdFS was performed to increase the affinity between the AdFS and wet biological tissue by introducing hydrophilic functional groups. The UV irradiated AdFS (UV-C10-AdFS) strongly adhered to porcine pleura within 2 min under wet conditions and showed higher burst strength compared with the original ApGltn (Org-ApGltn) sheet. Hematoxylin-eosin stained sections revealed that a dense UV-C10-AdFS layer remained on the surface of the porcine pleura even after burst strength measurement. Moreover, UV-C10-AdFS has excellent cytocompatibility and efficiently supports the growth of L929 cells. UV-C10-AdFS is a promising adhesive material for sealing wet biological tissue.


Assuntos
Gelatina/química , Pleura/efeitos dos fármacos , Adesivos Teciduais/química , Adesivos Teciduais/efeitos da radiação , Alaska , Animais , Linhagem Celular , Técnicas Eletroquímicas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Gadiformes/metabolismo , Gelatina/efeitos da radiação , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Camundongos , Pleura/efeitos da radiação , Polietilenoglicóis/química , Suínos , Resistência à Tração , Adesivos Teciduais/farmacologia , Raios Ultravioleta
20.
Oecologia ; 195(2): 355-365, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33439358

RESUMO

Climatic factors act on populations at multiple timescales leading to the separation of long-term climate and shorter-term weather effects. We used passerine counts from 1995 to 2019 in subarctic Alaska (Denali National Park, USA) to assess the impacts of the prior breeding season's weather on breeding season abundance and the impacts of climate measured through shifts in elevational distribution. Weather and climate appear to have had opposing effects on the abundance of some shrub-associated species as evidenced by a positive response to nesting phase temperature over a 1-year lag and a negative response to warming-induced shifts in shrub-dominated habitats over the long term. The latter response was indicated by declines in abundance which occurred in some part through portions of these populations shifting upslope of our fixed sampling frame. Overall, the abundance of species was related to one or more of the lagged effects of weather and the effects of weather alone drove nearly twofold variation in annual abundance in most species. The effect of nesting phase temperature was a strong positive predictor at both community and individual species levels, whereas arrival phase temperature had weak support at both levels. The effects of total precipitation during the nesting phase and snowmelt timing shared mixed support at community and species levels, but generally indicated higher abundance following seasons that were drier and had earlier snowmelt. Together, our findings of opposing effects of climatic variables at different timescales have implications for understanding the mechanisms of population and distributional change in passerines in the subarctic.


Assuntos
Mudança Climática , Passeriformes , Alaska , Animais , Estações do Ano , Temperatura , Tempo (Meteorologia)
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