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1.
Arch Environ Contam Toxicol ; 85(2): 140-146, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37584700

RESUMEN

Environmental damage caused by accidental discharges of pollutants depends in part on the degree of prior contamination, in that increased pollution of an already heavily contaminated region will usually be considered less detrimental than equivalent pollution of a pristine region. Quantitative comparisons of specific pollution events with the extent and severity of prior contamination are rare, owing to difficulties in identifying and assessing contaminants remaining from prior pollution events, and in some cases contaminants from natural sources. The 1989 Exxon Valdez oil spill (EVOS) presents an unusual opportunity to quantitatively evaluate residual contaminants from petroleum sources on shorelines of Prince William Sound (PWS), Alaska. Here, we evaluate surface oil contamination from Monterey Formation petroleum-derived residues (released into PWS from ruptured storage tanks during the 1964 earthquake) on 200 shoreline segments selected at random within the EVOS spill path. We compare these results with previously estimated contamination from the EVOS and from other human activities. Our results indicate that residual shoreline contamination from the EVOS is more than ~ 50% greater than the sum total from human activity sites, that residual contamination by Monterey Formation sources is negligible in comparison to that from the EVOS, and that most of the shorelines in PWS were as close to pristine prior to the EVOS as is likely to be found anywhere else worldwide.


Asunto(s)
Contaminación por Petróleo , Petróleo , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Humanos , Alaska , Contaminantes Químicos del Agua/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
2.
JAMA Netw Open ; 6(7): e2322505, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37428504

RESUMEN

Importance: Older patients using many prescription drugs (hyperpolypharmacy) may be at increased risk of adverse drug effects. Objective: To test the effectiveness and safety of a quality intervention intended to reduce hyperpolypharmacy. Design, Setting, and Participants: This randomized clinical trial allocated patients 76 years or older who used 10 or more prescription medications to a deprescribing intervention or to usual care (1:1 ratio) at an integrated health system with multiple preexisting deprescribing workflows. Data were collected from October 15, 2020, to July 29, 2022. Intervention: Physician-pharmacist collaborative drug therapy management, standard-of-care practice recommendations, shared decision-making, and deprescribing protocols administered by telephone over multiple cycles for a maximum of 180 days after allocation. Main Outcomes and Measures: Primary end points were change in the number of medications and in the prevalence of geriatric syndrome (falls, cognition, urinary incontinence, and pain) from 181 to 365 days after allocation compared with before randomization. Secondary outcomes were use of medical services and adverse drug withdrawal effects. Results: Of a random sample of 2860 patients selected for potential enrollment, 2470 (86.4%) remained eligible after physician authorization, with 1237 randomized to the intervention and 1233 to usual care. A total of 1062 intervention patients (85.9%) were reached and agreed to enroll. Demographic variables were balanced. The median age of the 2470 patients was 80 (range, 76-104) years, and 1273 (51.5%) were women. In terms of race and ethnicity, 185 patients (7.5%) were African American, 234 (9.5%) were Asian or Pacific Islander, 220 (8.9%) were Hispanic, 1574 (63.7%) were White (63.7%), and 257 (10.4%) were of other (including American Indian or Alaska Native, Native Hawaiian, or >1 race or ethnicity) or unknown race or ethnicity. During follow-up, both the intervention and usual care groups had slight reductions in the number of medications dispensed (mean changes, -0.4 [95% CI, -0.6 to -0.2] and -0.4 [95% CI, -0.6 to -0.3], respectively), with no difference between the groups (P = .71). There were no significant changes in the prevalence of a geriatric condition in the usual care and intervention groups at the end of follow-up and no difference between the groups (baseline prevalence: 47.7% [95% CI, 44.9%-50.5%] vs 42.9% [95% CI, 40.1%-45.7%], respectively; difference-in-differences, 1.0 [95% CI, -3.5 to 5.6]; P = .65). No differences in use of medical services or adverse drug withdrawal effects were observed. Conclusions and Relevance: In this randomized clinical trial from an integrated care setting with various preexisting deprescribing workflows, a bundled hyperpolypharmacy deprescribing intervention was not associated with reduction in medication dispensing, prevalence of geriatric syndrome, utilization of medical services, or adverse drug withdrawal effects. Additional research is needed in less integrated settings and in more targeted populations. Trial Registration: ClinicalTrials.gov Identifier: NCT05616689.


Asunto(s)
Deprescripciones , Humanos , Femenino , Anciano , Anciano de 80 o más Años , Masculino , Administración del Tratamiento Farmacológico , Alaska , Hawaii
3.
Int J Circumpolar Health ; 82(1): 2196047, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37161378

RESUMEN

In Arctic or extreme cold environments of Alaska, trauma care is complicated by large expanses of geography and lack of forward-positioned resources. This paper presents four hypothetical vignettes highlighting austere cold medical priorities: (1) traumatic hypothermia management as part of Tactical Combat Casualty Care (TCCC) is clinically and tactically important and hypothermia needs to be reprioritized in the MARCH algorithm to MhARCH; (2) at present it is unknown which TCCC recommended medical equipment/supplies will function as designed in the extreme cold; (3) ensuring advanced resuscitative care measures are available serves as a temporal bridge until casualties can receive damage control resuscitation (DCR); and (4) current systems for managing traumatic hypothermia in TCCC and casualty evacuation (CASEVAC) are insufficient. In conclusion, numerous assessments recognise the DoD's current solutions for employing medical forces in Arctic operations are not optimally postured to save lives. There should be a joint standard for fielding an arctic supplement to current medical equipment sets. A new way of thinking in terms of an "ecosystem" approach of immediate casualty protection and movement in CASEVAC doctrine is needed to optimise these "Golden Minutes."


Asunto(s)
Frío Extremo , Hipotermia , Humanos , Hipotermia/terapia , Alaska , Suplementos Dietéticos , Ecosistema
4.
Ear Hear ; 44(5): 1078-1087, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36939709

RESUMEN

OBJECTIVES: The aim of this study is to present an explanatory model of hearing loss in the Bering Strait region of Alaska in order to contextualize the results of a cluster randomized trial and propose implications for regional hearing-related health care. DESIGN: To promote ecological validity, or the generalizability of trial findings to real world experiences, qualitative methods (focus groups and interviews) were used within a mixed methods cluster randomized trial evaluating school hearing screening and follow-up processes in 15 communities in the Bering Strait region of Alaska. Focus groups were held between April and August 2017, and semistructured interviews were conducted between December 2018 and August 2019. Convenience sampling was used for six of the 11 focus groups to capture broad community feedback. Purposive sampling was used for the remaining five focus groups and for all interviews to capture a variety of experiences with hearing loss. Audio recordings of focus groups and interviews were transcribed, and both notes and transcripts were deidentified. All notes and transcripts were included in the analysis. The constant comparative method was used to develop a codebook by iteratively moving between transcripts and preliminary themes. Researchers then used this codebook to code data from all focus groups and interviews using qualitative analysis software (NVIVO 12, QSR International) and conducted thematic analyses to distill the findings presented in this article. RESULTS: Participants in focus groups (n = 116) and interviews (n = 101) shared perspectives in three domains: etiology, impact, and treatment of hearing loss. Regarding etiology, participants emphasized noise-induced hearing loss but also discussed infection-related hearing loss and various causes of ear infections. Participants described the impact of hearing loss on subsistence activities, while also detailing social, academic, and economic consequences. Participants described burdensome treatment pathways that are repetitive and often travel and time intensive. Communication breakdowns within these pathways were also described. Some participants spoke positively of increased access via onsite hearing health care services in "field clinics" as well as via telemedicine services. Others described weaknesses in these processes (infrequent field clinics and communication delays in telemedicine care pathways). Participants also described home remedies and stigma surrounding the treatment for hearing loss. CONCLUSIONS: Patient-centered health care requires an understanding of context. Explanatory models of illness are context-specific ways in which patients and their networks perceive and describe the experience of an illness or disability. In this study, we documented explanatory models of hearing loss to foster ecological validity and better understand the relevance of research findings to real-life hearing-related experiences. These findings suggest several areas that should be addressed in future implementation of hearing health care interventions elsewhere in rural Alaska, including management of repetitious treatments, awareness of infection-mediated hearing loss, mistrust, and communication breakdowns. For hearing-related health care in this region, these findings suggest localized recommendations for approaches for prevention and treatment. For community-based hearing research, this study offers an example of how qualitative methods can be used to generate ecologically valid (i.e., contextually grounded) findings.


Asunto(s)
Sordera , Pérdida Auditiva Provocada por Ruido , Telemedicina , Humanos , Alaska/epidemiología , Atención a la Salud , Pérdida Auditiva Provocada por Ruido/epidemiología , Investigación Cualitativa
5.
J Nutr ; 152(12): 2761-2770, 2023 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-36138493

RESUMEN

BACKGROUND: In animal studies, a meal containing Alaska pollack protein (APP) induces fast-twitch muscle hypertrophy. To our knowledge, no interventional studies have examined the benefits of APP intake on muscle mass and muscle weakness and the prevention of sarcopenia in older individuals. OBJECTIVES: We evaluated the effects of APP intake on skeletal muscle mass, muscle strength, and physical performance among healthy community-dwelling older Japanese women. METHODS: In this double-blind randomized controlled trial, healthy women ≥ 65 y old were allocated to an APP or whey protein control (CON) group. Participants ingested test protein meals (5.0-5.1 g protein/serving) daily for 24 wk. Between-group differences in the change of skeletal muscle mass index (SMI) as the primary outcome and muscle strength as a secondary outcome were tested using multifrequency BIA and a handheld dynamometer, respectively, at baseline, and 4, 12, and 24 wk. The mean changes in the measured primary and secondary outcome variables from baseline to 4, 12, and 24 wk were compared using unpaired t tests. RESULTS: There were no between-group differences in nutritional status, food intake, or total energy and protein intakes at baseline, 12 wk, or 24 wk. The change in SMI was 0.12 kg/m2 (95% CI: 0.01, 0.23 kg/m2) and 0.11 kg/m2 (95% CI: 0.03, 0.19 kg/m2) greater in the APP group than in the CON group at 12 wk and 24 wk (P ≤ 0.03) and knee extension strength was 0.07 Nm/kg BW (95% CI: 0.02, 0.12 Nm/kg BW) and 0.05 Nm/kg BW (95% CI: 0.00, 0.09 Nm/kg BW) higher in the APP group than in the CON group at these times (P ≤ 0.015), respectively. The groups did not differ at 4 wk. CONCLUSIONS: Daily intake of a meal containing APP compared with whey protein increases skeletal muscle mass and lower-extremity muscle strength in healthy older women, suggesting that an APP-containing meal may be useful in the prevention of sarcopenia in this group.This trial was registered at as UMIN000035718.


Asunto(s)
Sarcopenia , Animales , Femenino , Sarcopenia/prevención & control , Sarcopenia/metabolismo , Proteína de Suero de Leche/farmacología , Músculo Esquelético , Alaska , Fuerza Muscular , Comidas , Método Doble Ciego , Suplementos Dietéticos , Proteínas en la Dieta/farmacología , Proteínas en la Dieta/metabolismo
6.
Mar Pollut Bull ; 173(Pt A): 113016, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34653886

RESUMEN

The combustion efficiency of simulated at-sea surface oil burns (in situ burns) was determined in a 63 m3 tank while testing varied boom configurations and air-assist nozzles in the presence and absence of waves. Combustion efficiencies of Alaska North Slope oil based on unburned carbon in the plume emissions ranged from 85% to 93% while values based on oil mass loss ranged from 89% to 99%. A four-fold variation in PM2.5 emission factors was observed from the test conditions. The most effective burns in terms of reduced emissions and post-burn residue concentration of total petroleum hydrocarbons were those that had high length to width boom ratios resulting in higher flame front surface area exposure to ambient air. The amount of oil mass lost was not related to any combustion efficiency parameters measured in the plume, representing a potential tradeoff between unburnt oil and air pollution.


Asunto(s)
Contaminación del Aire , Contaminación por Petróleo , Petróleo , Alaska , Hidrocarburos , Contaminación por Petróleo/análisis
7.
J Cross Cult Gerontol ; 36(1): 43-67, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33566251

RESUMEN

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.


Asunto(s)
Envejecimiento/psicología , Envejecimiento Saludable , Satisfacción Personal , Calidad de Vida , Espiritualidad , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Alaska , Cultura , Femenino , Estado de Salud , Humanos , Masculino , Salud Mental , Investigación Cualitativa , Religión y Psicología
8.
Mar Pollut Bull ; 161(Pt B): 111718, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33038711

RESUMEN

Spectroscopic techniques including X-ray fluorescence (XRF) and attenuated total reflectance - Fourier transform infrared spectroscopy (ATR-FTIR) are used to examine oil residues persisting on shorelines in Prince William Sound that originate from the 1989 Exxon Valdez oil spill and oil released as a consequence of the 1964 Great Alaska earthquake. When coupled to classification models, ATR-FTIR and XRF spectral data can be used to distinguish between the two sources of oil with 92% and 86% success rates for the two techniques respectively. Models indicate that the ATR-FTIR data used to determine oil source includes the CO stretch, the twisting-scissoring of the CH2 group, and the CC stretch. For XRF data, decision tree models primarily utilize the abundance of nickel and zinc present in the oil as a means to classify source. This approach highlights the utility of rapid, field-based spectroscopic techniques to distinguish different inputs of oil to coastal environments.


Asunto(s)
Petróleo , Contaminantes Químicos del Agua , Alaska , Monitoreo del Ambiente , Petróleo/análisis , Sonido , Contaminantes Químicos del Agua/análisis
9.
Prev Chronic Dis ; 17: E102, 2020 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-32915131

RESUMEN

INTRODUCTION: Tobacco kills over half a million adults annually in the United States. Most smokers want to quit, and over 400,000 call state-funded quitlines for help each year. Marijuana use among tobacco users is common and may impede quitting, but co-use rates among quitline callers are unknown. The purpose of our observational study was to describe marijuana use among quitline callers in states with legalized marijuana. METHODS: Participants were 1,059 smokers aged 21 or older from Oregon, Alaska, and Washington, DC, who called quitlines from September through December 2016. Data on quitline callers' demographics, tobacco and marijuana use, and quitline use were collected. We used χ2 and regression analyses to compare marijuana users with nonusers on demographic characteristics and quitline use. RESULT: Among quitline callers in our study, 24% reported using marijuana in the past 30 days: 28.9% in Alaska, 16.7% in Washington, DC, and 25.0% in Oregon (P = .009). Current users, compared with non-users (n = 772), were less likely to be women (48.4% vs 62.0%, respectively, P < .001). Current marijuana users were less likely to be given nicotine replacement therapy (68.4%) than current nonusers (74.1%) (P < .001), but more likely to complete 3 or more counseling calls (P = .005). Of those who used marijuana in the past 30 days, 62.3% used marijuana on 1 to 19 days, 9.0% used on 20 to 29 days, and 28.7% on all 30 days. Among current marijuana users, the percentage who wanted to quit or reduce marijuana use (42.6%) was higher in Alaska (54.6%) and the District of Columbia (56.8%) than in Oregon (37.9%), P = .03. CONCLUSION: One in 4 quitline callers reported past 30-day marijuana use. Given that nearly half (43%) wanted to reduce marijuana use, addressing co-use may be an important addition to quitline treatment. Future studies should assess co-use effects on tobacco cessation outcomes and explore combined treatment or bidirectional referrals between quitlines and marijuana treatment providers.


Asunto(s)
Consejo , Uso de la Marihuana , Cese del Hábito de Fumar , Adulto , Alaska , District of Columbia , Femenino , Humanos , Masculino , Oregon , Uso de Tabaco , Adulto Joven
10.
PLoS One ; 15(8): e0224056, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32813718

RESUMEN

Many recent studies assessing fruit productivity of plants in the boreal forest focus on interannual variability across a forested region, rather than on environmental variability within the forest. Frequency and severity of wildfires in the boreal forest affect soil moisture, canopy, and community structure at the landscape level, all of which may influence overall fruit production at a site directly or indirectly. We evaluated how fruit production in two boreal shrubs, Vaccinium uliginosum (blueberry) and V. vitis-idaea (lingonberry), was explained by factors associated with resource availability (such as canopy cover and soil conditions) and pollen limitation (such as floral resources for pollinators and pollen deposition) across boreal forest sites of Interior Alaska in 2017. We classified our study sites into upland and lowland sites, which differed in elevation, soil moisture, and active layer. We found that resource and pollen limitation differed between the two species and between uplands and lowlands. Lingonberry was more pollen limited than blueberry, and plants in lowland sites were more pollen limited relative to other sites while plants in upland sites were relatively more resource limited. Additionally, canopy cover had a significant negative effect in upland sites on a ramet's investment in reproductive tissues and leaves versus structural growth, but little effect in lowland sites. These results point to importance of including pollinator service as well as resource availability in predictions for changes in berry abundance.


Asunto(s)
Arándanos Azules (Planta)/metabolismo , Frutas/metabolismo , Vaccinium vitis-Idaea/metabolismo , Alaska , Conservación de los Recursos Naturales , Bosques , Frutas/química , Polen/química , Polen/metabolismo , Polinización , Reproducción , Taiga
11.
Sci Total Environ ; 744: 140787, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-32717470

RESUMEN

Mercury (Hg) can be neurotoxic to mammals and impact reproduction, whereas selenium (Se) is an important antioxidant known to ameliorate some adverse effects of Hg. Total Hg concentrations ([THg]) were measured in lanugo (pelage grown in utero) of 812 Steller sea lion (Eumetopias jubatus) pups across Alaska and Russia to assess fetal exposure during late gestation. The molar ratio of total Se to THg (TSe:THg) was determined in whole blood collected from 291 pups. Stable isotope ratios of carbon and nitrogen were measured in sections of vibrissae (whiskers, n = 498) and in lanugo (n = 480) of pups grown during late gestation to track diet variations among adult females that can drive Hg and Se exposure during this critical fetal development period. Lanugo [THg] ranged from 1.4 to 73.7 µg/g dry weight with the lowest median [THg] in Southeast Alaska. Pups from the Western Aleutian Islands had higher median lanugo [THg] than pups from other metapopulations in Alaska. Over 25% of pups in the Western Aleutian Islands had [THg] above published risk thresholds (20 µg/g) for other mammals. Whole blood molar TSe:THg was significantly lower in the Western Aleutian Islands and in some parts of the Central Aleutian Islands with higher molar ratios found in the Eastern Aleutian Islands and Central Gulf of Alaska. This suggests a limitation on potential protective functions of Se in the western regions with the highest relative [THg]. The Central Aleutian Island pups with [THg] over 20 µg/g had higher δ15N ratios than pups with lower [THg] suggesting dams consuming higher trophic level prey is a key driver for Hg exposure. However, regional differences likely reflect variability in diet of the dam during gestation and in Hg food web dynamics between oceanic regimes east and west of key passes in the Aleutian Islands.


Asunto(s)
Mercurio/análisis , Leones Marinos , Selenio , Contaminantes Químicos del Agua , Alaska , Animales , Femenino , Embarazo , Federación de Rusia
12.
Proc Natl Acad Sci U S A ; 117(27): 15443-15449, 2020 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-32571905

RESUMEN

The assassination of Julius Caesar in 44 BCE triggered a power struggle that ultimately ended the Roman Republic and, eventually, the Ptolemaic Kingdom, leading to the rise of the Roman Empire. Climate proxies and written documents indicate that this struggle occurred during a period of unusually inclement weather, famine, and disease in the Mediterranean region; historians have previously speculated that a large volcanic eruption of unknown origin was the most likely cause. Here we show using well-dated volcanic fallout records in six Arctic ice cores that one of the largest volcanic eruptions of the past 2,500 y occurred in early 43 BCE, with distinct geochemistry of tephra deposited during the event identifying the Okmok volcano in Alaska as the source. Climate proxy records show that 43 and 42 BCE were among the coldest years of recent millennia in the Northern Hemisphere at the start of one of the coldest decades. Earth system modeling suggests that radiative forcing from this massive, high-latitude eruption led to pronounced changes in hydroclimate, including seasonal temperatures in specific Mediterranean regions as much as 7 °C below normal during the 2 y period following the eruption and unusually wet conditions. While it is difficult to establish direct causal linkages to thinly documented historical events, the wet and very cold conditions from this massive eruption on the opposite side of Earth probably resulted in crop failures, famine, and disease, exacerbating social unrest and contributing to political realignments throughout the Mediterranean region at this critical juncture of Western civilization.


Asunto(s)
Cambio Climático/historia , Clima Frío/efectos adversos , Desastres/historia , Mundo Romano/historia , Erupciones Volcánicas/efectos adversos , Alaska , Clima , Productos Agrícolas/historia , Hambruna/historia , Historia Antigua , Cubierta de Hielo , Región Mediterránea , Política , Erupciones Volcánicas/historia
13.
Sci Total Environ ; 727: 138723, 2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32334234

RESUMEN

Salinity variability strongly affects the behaviors of oil degrading bacteria for spilled oil biodegradation in the marine environment. However, limited studies explored the strategies of microbes on salinity-mediated crude oil biodegradation. In this study, a halotolerant bio-emulsifier producer, Exiguobacterium sp. N41P, was examined as a model strain for Alaska North Slope (ANS) crude oil (0.5%, v/v) biodegradation. Results indicated that Exiguobacterium sp. N41P could tolerant a wide range of salinity (0-120 g/L NaCl) and achieve the highest degradation efficiency under the salinity of 15 g/L NaCl due to the highest biofilm formation ability. Moreover, increased salinity induced decreased cell surface hydrophobicity and a migration of microbial growth from oil phase to aqueous phase, leading to limited bio-emulsifier productivity and depressed degradation of insoluble long-chain n-alkanes while enhancing the degradation of relative soluble naphthalene. Research findings illustrated the microbial eco-physiological mechanism for spilled oil biodegradation under diverse salinities and advanced the understanding of sophisticated marine crude oil biodegradation process.


Asunto(s)
Contaminación por Petróleo , Petróleo , Alaska , Biodegradación Ambiental , Salinidad
14.
Environ Sci Technol ; 54(11): 6456-6467, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32267150

RESUMEN

The long-term ecological impacts of the Exxon Valdez oil spill (EVOS) are compared to two extensively studied and more recent large spills: Deepwater Horizon (DWH) and the Hebei Spirit oil spill (HSOS). Each of the three spills differed in magnitude and duration of oil released, environmental conditions, ecological communities, response and clean up measures, and ecological recovery. The EVOS began on March 24, 1989, and released 40.8 million liters of Alaska North Slope crude oil into the cold, nearly pristine environment of Prince William Sound, Alaska. EVOS oiled wildlife and rocky intertidal shorelines and exposed early life stages of fish to embryotoxic levels of polycyclic aromatic hydrocarbons (PAH). Long-term impacts following EVOS were observed on seabirds, sea otters, killer whales, and subtidal communities. The DWH spill began on April 20, 2010, and released 507 million liters of light Louisiana crude oil from 1600 m on the ocean floor into the Gulf of Mexico over an 87-day period. The DWH spill exposed a diversity of complex aquatic communities in the deep ocean, offshore pelagic areas, and coastal environments to petroleum hydrocarbons. Large-scale persistent ecological effects included impacts to deep ocean corals, failed recruitment of oysters over multiple years, damage to coastal wetlands, and reduced dolphin, sea turtle, and seabird populations. The HSOS began on December 7, 2007, and released approximately 13 million liters of Middle East crude oils into ecologically sensitive areas of the Taean area of western Korea. Environmental conditions and the extensive initial cleanup of HSOS oil stranded on shorelines limited the long-term impacts to changes in composition and abundance of intertidal benthic communities. Comparisons of EVOS, DWH, and HSOS show the importance and complexity of the interactions among the environment, oil spill dynamics, affected ecological systems, and response actions.


Asunto(s)
Contaminación por Petróleo , Petróleo , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Alaska , Animales , Golfo de México , Louisiana , Petróleo/análisis , Contaminación por Petróleo/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , República de Corea , Contaminantes Químicos del Agua/análisis
15.
Prev Chronic Dis ; 17: E12, 2020 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-32027813

RESUMEN

PURPOSE AND OBJECTIVES: The purpose of the Traditional Foods Project (TFP) was to implement and evaluate a community-defined set of strategies to address type 2 diabetes by focusing on traditional foods, physical activity, and social support. The TFP sought to answer 2 questions: first, how do we increase and sustain community access to traditional foods and related activities to promote health and help prevent type 2 diabetes? Second, how do we evaluate interventions across culturally and geographically diverse communities to demonstrate success? INTERVENTION APPROACH: Public health interventions are most effective when communities integrate their own cultures and history into local programs. The food sovereignty movement among American Indians/Alaska Natives and indigenous populations globally offers ways to address public health issues such as chronic diseases like type 2 diabetes. Historical, economic, social, and environmental determinants of health are critical to understanding the disease. EVALUATION METHODS: During 2008-2014, seventeen tribal TFP partners implemented locally designed interventions and collected quantitative and qualitative data in 3 domains: traditional foods, physical activity, and social support. Partners entered data into a jointly developed evaluation tool and presented additional program data at TFP meetings. Partner observations about the effect of the TFP were gathered in planned discussions. RESULTS: Quantitative results indicate collaborative community engagement and sustained interventions such as gardening, availability of healthy foods across venues, new health practices, health education, and storytelling. Qualitative results demonstrate the importance of tribally driven programs, underscoring the significance of traditional foods in relation to land, identity, food sovereignty, and food security. IMPLICATIONS FOR PUBLIC HEALTH: Traditional foods and food sovereignty are important areas for American Indian/Alaska Native communities to address the public health issues of chronic disease, specifically type 2 diabetes, locally and nationwide.


Asunto(s)
Diabetes Mellitus Tipo 2/prevención & control , Dieta Saludable/etnología , Promoción de la Salud/organización & administración , Determinantes Sociales de la Salud , Alaska , Cultura , Dieta Saludable/métodos , Dieta Saludable/estadística & datos numéricos , Ejercicio Físico , Conocimientos, Actitudes y Práctica en Salud , Disparidades en el Estado de Salud , Humanos , Evaluación de Programas y Proyectos de Salud , Investigación Cualitativa , Características de la Residencia , Apoyo Social
16.
Mar Pollut Bull ; 153: 110954, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32056858

RESUMEN

The majority of aquatic toxicity data for petroleum products has been limited to a few intensively studied crude oils and Corexit chemical dispersants, and acute toxicity testing in two standard estuarine test species: mysids (Americamysis bahia) and inland silversides (Menidia beryllina). This study compared the toxicity of two chemical dispersants commonly stock piled for spill response (Corexit EC9500A®, Finasol®OSR 52), three less studied agents (Accell Clean®DWD dispersant; CytoSol® surface washing agent; Gelco200® solidifier), and three crude oils differing in hydrocarbon composition (Dorado, Endicott, Alaska North Slope). Consistent with listings on the U.S. National Contingency Plan Product Schedule, general rank order toxicity was greatest for dispersants and lowest for the solidifier. The results indicate that freshwater species can have similar sensitivity as the conventionally tested mysids and silversides, and that the sea urchin (Arbacia punctulata) appears to be a reasonable addition to increase taxa diversity in standardized oil agent testing.


Asunto(s)
Contaminación por Petróleo , Petróleo/toxicidad , Contaminantes Químicos del Agua/toxicidad , Alaska , Animales , Organismos Acuáticos/efectos de los fármacos , Tensoactivos/toxicidad , Pruebas de Toxicidad Aguda
17.
Nutrients ; 12(1)2020 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-31963802

RESUMEN

Excess alcohol consumption is a top risk factor for death and disability. Fatty liver will likely develop and the risk of liver disease increases. We have previously demonstrated that an essential amino acid supplement (EAAS) improved protein synthesis and reduced intrahepatic lipid in the elderly. The purpose of this exploratory pilot study was to initiate the evaluation of EAAS on intrahepatic lipid (IHL), body composition, and blood lipids in individuals with mild to moderate alcohol use disorder (AUD). Following consent, determination of eligibility, and medical screening, 25 participants (18 males at 38 ± 15 years/age and 7 females at 34 ± 18 years/age) were enrolled and randomly assigned to one of two dosages: a low dose (LD: 8 g of EAAS twice/day (BID)) or high dose (HD: 13 g of EAAS BID). Five of the twenty-five enrolled participants dropped out of the intervention. Both groups consumed the supplement BID for 4 weeks. Pre- and post-EAAS administration, IHL was determined using magnetic resonance imaging/spectroscopy, body composition was analyzed using dual-energy X-ray absorptiometry, and blood parameters were measured by LabCorp. T-tests were used for statistical analysis and considered significant at p < 0.05. While there was no significant change in IHL in the LD group, there was a significant 23% reduction in IHL in the HD group (p = 0.02). Fat mass, lean tissue mass, bone mineral content, and blood lipids were not altered. Post-EAAS phosphatidylethanol was elevated and remained unchanged in LD at 407 ± 141 ng/mL and HD at 429 ± 196 ng/mL, indicating chronic and excess alcohol consumption. The HD of the proprietary EAAS formulation consumed BID seemed to lower IHL in individuals with mild to moderate AUD. We suggest that further studies in a larger cohort be conducted to more completely address this important area of investigation.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Aminoácidos Esenciales/administración & dosificación , Suplementos Dietéticos , Hígado Graso Alcohólico/tratamiento farmacológico , Lípidos/sangre , Hígado/efectos de los fármacos , Adulto , Alaska , Aminoácidos Esenciales/efectos adversos , Biomarcadores/sangre , Composición Corporal/efectos de los fármacos , Suplementos Dietéticos/efectos adversos , Hígado Graso Alcohólico/etiología , Hígado Graso Alcohólico/metabolismo , Femenino , Humanos , Hígado/metabolismo , Masculino , Persona de Mediana Edad , Proyectos Piloto , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
18.
Glob Chang Biol ; 26(2): 682-696, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31596019

RESUMEN

Arctic and boreal ecosystems play an important role in the global carbon (C) budget, and whether they act as a future net C sink or source depends on climate and environmental change. Here, we used complementary in situ measurements, model simulations, and satellite observations to investigate the net carbon dioxide (CO2 ) seasonal cycle and its climatic and environmental controls across Alaska and northwestern Canada during the anomalously warm winter to spring conditions of 2015 and 2016 (relative to 2010-2014). In the warm spring, we found that photosynthesis was enhanced more than respiration, leading to greater CO2 uptake. However, photosynthetic enhancement from spring warming was partially offset by greater ecosystem respiration during the preceding anomalously warm winter, resulting in nearly neutral effects on the annual net CO2 balance. Eddy covariance CO2 flux measurements showed that air temperature has a primary influence on net CO2 exchange in winter and spring, while soil moisture has a primary control on net CO2 exchange in the fall. The net CO2 exchange was generally more moisture limited in the boreal region than in the Arctic tundra. Our analysis indicates complex seasonal interactions of underlying C cycle processes in response to changing climate and hydrology that may not manifest in changes in net annual CO2 exchange. Therefore, a better understanding of the seasonal response of C cycle processes may provide important insights for predicting future carbon-climate feedbacks and their consequences on atmospheric CO2 dynamics in the northern high latitudes.


Asunto(s)
Ecosistema , Fotosíntesis , Alaska , Regiones Árticas , Canadá , Ciclo del Carbono , Dióxido de Carbono , Cambio Climático , Estaciones del Año
19.
Chemosphere ; 239: 124783, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31726517

RESUMEN

This research concerned radioactivity of lichens and mosses from coastal zones of the Canadian Arctic and Alaska. Over 50 samples were collected from 7 positions during two scientific expeditions in 2012 and 2013. The tundra contamination caused by anthropogenic radionuclides was relatively low, reaching mean values with SD's of: 17.4 ±â€¯3.5 Bq/kg for 90Sr, 14.0 ±â€¯2.9 Bq/kg for 134Cs, 38.4 ±â€¯7.5 Bq/kg for 137Cs, 0.86 ±â€¯0.24 Bq/kg for 239+240Pu, 0.065 ±â€¯0.017 Bq/kg for 238Pu and 0.50 ±â€¯0.13 Bq/kg for 241Am. The increase of activity concentration with increasing latitudes was noticed mostly in regard to 90Sr, Pu isotopes and 241Am. The analysis of isotopic ratios exhibited dominant contribution of the global fallout (+SNAP 9A satellite re-entry fallout) for the presence of plutonium isotopes and 241Am. The Fukushima fallout signature was identified in a few lichens from Alaska. However, the influence of additional unknown factor on the occurrence of 90Sr and 137Cs has been detected in western part of Canadian Arctic. Natural radioisotopes of thorium and uranium were found throughout the entire investigated region and the average values of activity concentration with SD's were as follows: 2.92 ±â€¯0.47 Bq/kg for 230Th, 2.61 ±â€¯0.48 Bq/kg for 232Th, 4.32 ±â€¯0.80 Bq/kg for 234U and 3.97 ±â€¯0.71 Bq/kg for 238U. Examined Western Arctic tundra was not affected with any technically enhanced natural radioactivity.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Briófitas/química , Líquenes/química , Ceniza Radiactiva/análisis , Contaminantes Radiactivos del Suelo/análisis , Contaminantes Radiactivos del Agua/análisis , Alaska , Regiones Árticas , Canadá , Radioisótopos de Cesio/análisis , Accidente Nuclear de Fukushima , Plutonio/análisis , Monitoreo de Radiación/métodos , Torio/análisis , Uranio/análisis
20.
PLoS One ; 14(11): e0225271, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31747438

RESUMEN

Understanding the entirety of basin-scale C cycling (DOC fluxes and CO2 exchanges) are central to a holistic perspective of boreal forest biogeochemistry today. Shifts in the timing and magnitude of dissolved organic carbon (DOC) delivery in streams and eventually into oceans can be expected, while simultaneously CO2 emission may exceed CO2 fixation, leading to forests becoming stronger CO2 sources than sinks amplifying rising trace gases in the atmosphere. At May Creek, a representative late-successional boreal forest watershed at the headwaters of the Copper River Basin, Alaska, we quantified the seasonality of DOC flux and landscape-scale CO2 exchange (eddy covariance) over two seasonal cycles. We deployed in situ fDOM and conductivity sensors, performed campaign sampling for water quality (DOC and water isotopes), and used fluorescence spectroscopy to ascertain DOC character. Simultaneously, we quantified net CO2 exchange using a 100 ft eddy covariance tower. Results indicate DOC exports were pulse-driven and mediated by precipitation events. Both frequency and magnitude of pulse-driven DOC events diminished as the seasonal thaw depth deepened, with inputs from terrestrial sources becoming major contributors to the DOC pool with decreasing snowmelt contribution to the hydrograph. A three-component parallel factorial analysis (PARAFAC) model indicated DOC liberated in late-season may be bioavailable (tyrosine-like). Combining Net Ecosystem Exchange (NEE) measurements indicate that the May Creek watershed fixes 142-220 g C m-2 yr-1 and only 0.40-0.57 g C m-2 yr-1 is leached out as DOC. Thus, the May Creek watershed and similar mature spruce forest dominated watersheds in the Copper River Basin are currently large ecosystem C sinks and exceeding C conservative. An understanding of DOC fluxes from Gulf of Alaska watersheds is important for characterizing future climate change-induced seasonal shifts.


Asunto(s)
Ciclo del Carbono , Alaska , Simulación por Computador , Bosques , Ríos , Estaciones del Año , Tiempo (Meteorología)
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