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https://www.readbyqxmd.com/read/28095073/preclinical-and-potential-applications-of-common-western-herbal-supplements-as-complementary-treatment-in-parkinson-s-disease
#1
Luke A Morgan, Oliver Grundmann
Parkinson's disease (PD) is a neurological disorder with a complex pathological etiology, which is not fully understood. Progression of PD may be the result of a buildup of iron in the substantia nigra, microglia-mediated neuroinflammation, dysfunctional mitochondria, or abnormal protein handling. Dopamine is the main neurotransmitter affected, but as the disease progresses, a decrease in all the brain's biogenic amines occurs. Current medication used in the treatment of PD aims to prevent the breakdown of dopamine or increase dopaminergic neurotransmission in the central nervous system...
January 17, 2017: Journal of Dietary Supplements
https://www.readbyqxmd.com/read/28092384/emerging-investigator-series-a-14-year-depositional-ice-record-of-perfluoroalkyl-substances-in-the-high-arctic
#2
John J MacInnis, Katherine French, Derek C G Muir, Christine Spencer, Alison Criscitiello, Amila O De Silva, Cora J Young
To improve understanding of long-range transport of perfluoroalkyl substances to the High Arctic, samples were collected from a snow pit on the Devon Ice Cap in spring 2008. Snow was analyzed for perfluoroalkyl acids (PFAAs), including perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs), as well as perfluorooctane sulfonamide (FOSA). PFAAs were detected in all samples dated from 1993 to 2007. PFAA fluxes ranged from <1 to hundreds of ng per m(2) per year. Flux ratios of even-odd PFCA homologues were mostly between 0...
January 16, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28088543/transformation-of-terrestrial-organic-matter-along-thermokarst-affected-permafrost-coasts-in-the-arctic
#3
George Tanski, Hugues Lantuit, Saskia Ruttor, Christian Knoblauch, Boris Radosavljevic, Jens Strauss, Juliane Wolter, Anna M Irrgang, Justine Ramage, Michael Fritz
The changing climate in the Arctic has a profound impact on permafrost coasts, which are subject to intensified thermokarst formation and erosion. Consequently, terrestrial organic matter (OM) is mobilized and transported into the nearshore zone. Yet, little is known about the fate of mobilized OM before and after entering the ocean. In this study we investigated a retrogressive thaw slump (RTS) on Qikiqtaruk - Herschel Island (Yukon coast, Canada). The RTS was classified into an undisturbed, a disturbed (thermokarst-affected) and a nearshore zone and sampled systematically along transects...
January 11, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28079014/predicting-cognitive-decline-across-four-decades-in-mutation-carriers-and-non-carriers-in-autosomal-dominant-alzheimer-s-disease
#4
Ove Almkvist, Elena Rodriguez-Vieitez, Steinunn Thordardottir, Kaarina Amberla, Karin Axelman, Hans Basun, Anne Kinhult-Ståhlbom, Lena Lilius, Anne Remes, Lars-Olof Wahlund, Matti Viitanen, Lars Lannfelt, Caroline Graff
OBJECTIVES: The aim of this study was to investigate cognitive performance including preclinical and clinical disease course in carriers and non-carriers of autosomal-dominant Alzheimer's disease (adAD) in relation to multiple predictors, that is, linear and non-linear estimates of years to expected clinical onset of disease, years of education and age. METHODS: Participants from five families with early-onset autosomal-dominant mutations (Swedish and Arctic APP, PSEN1 M146V, H163Y, and I143T) included 35 carriers (28 without dementia and 7 with) and 44 non-carriers...
January 12, 2017: Journal of the International Neuropsychological Society: JINS
https://www.readbyqxmd.com/read/28078050/complete-genome-sequence-of-lutibacter-profundi-lp1-t-isolated-from-an-arctic-deep-sea-hydrothermal-vent-system
#5
Juliane Wissuwa, Sven Le Moine Bauer, Ida Helene Steen, Runar Stokke
Lutibacter profundi LP1(T) within the family Flavobacteriaceae was isolated from a biofilm growing on the surface of a black smoker chimney at the Loki's Castle vent field, located on the Arctic Mid-Ocean Ridge. The complete genome of L. profundi LP1(T) is the first genome to be published within the genus Lutibacter. L. profundi LP1(T) consists of a single 2,966,978 bp circular chromosome with a GC content of 29.8%. The genome comprises 2,537 protein-coding genes, 40 tRNA species and 2 rRNA operons. The microaerophilic, organotrophic isolate contains genes for all central carbohydrate metabolic pathways...
2017: Standards in Genomic Sciences
https://www.readbyqxmd.com/read/28075353/biochemical-and-structural-insights-into-a-novel-thermostable-%C3%AE-1-3-galactosidase-from-marinomonas-sp-bsi20414
#6
Haitao Ding, Qian Zeng, Lili Zhou, Yong Yu, Bo Chen
A novel β-1,3-galactosidase, designated as MaBGA (β-galactosidase from Marinomonas sp. BSi20414), was successfully purified to homogeneity from Marinomonas sp. BSi20414 isolated from Arctic sea ice by ammonium sulfate precipitation and anion exchange chromatography, resulting in an 8.12-fold increase in specific activity and 9.9% recovery in total activity. MaBGA displayed its maximum activity at pH 6.0 and 60 °C, and maintained at least 90% of its initial activity over the pH range of 5.0-8.0 after incubating for 1 h...
January 8, 2017: Marine Drugs
https://www.readbyqxmd.com/read/28075009/the-physiological-costs-of-prey-switching-reinforce-foraging-specialization
#7
Oliver E Hooker, Travis E Van Leeuwen, Colin E Adams
Sympatric speciation is thought to be strongly linked to resource specialization with alternative resource use acting as a fundamental agent driving divergence. However, sympatric speciation through niche expansion is dependent on foraging specialization being consistent over space and time. Standard metabolic rate is the minimal maintenance metabolic rate of an ectotherm in a post-absorptive and inactive state and can constitute a significant portion of an animal's energy budget; thus standard metabolic rate and growth rate are two measures frequently used as an indication of the physiological performance of individuals...
January 11, 2017: Journal of Animal Ecology
https://www.readbyqxmd.com/read/28073550/growth-and-bioactive-secondary-metabolites-of-arctic-protoceratium-reticulatum-dinophyceae
#8
Manuel Sala-Pérez, Tilman J Alpermann, Bernd Krock, Urban Tillmann
Harmful algal blooms are mainly caused by marine dinoflagellates and are known to produce potent toxins that may affect the ecosystem, human activities and health. Such events have increased in frequency and intensity worldwide in the past decades. Numerous processes involved in Global Change are amplified in the Arctic, but little is known about species specific responses of arctic dinoflagellates. The aim of this work was to perform an exhaustive morphological, phylogenetical and toxinological characterization of Greenland Protoceratium reticulatum and, in addition, to test the effect of temperature on growth and production of bioactive secondary metabolites...
May 2016: Harmful Algae
https://www.readbyqxmd.com/read/28073526/prevalence-of-algal-toxins-in-alaskan-marine-mammals-foraging-in-a-changing-arctic-and-subarctic-environment
#9
Kathi A Lefebvre, Lori Quakenbush, Elizabeth Frame, Kathy Burek Huntington, Gay Sheffield, Raphaela Stimmelmayr, Anna Bryan, Preston Kendrick, Heather Ziel, Tracey Goldstein, Jonathan A Snyder, Tom Gelatt, Frances Gulland, Bobette Dickerson, Verena Gill
Current climate trends resulting in rapid declines in sea ice and increasing water temperatures are likely to expand the northern geographic range and duration of favorable conditions for harmful algal blooms (HABs), making algal toxins a growing concern in Alaskan marine food webs. Two of the most common HAB toxins along the west coast of North America are the neurotoxins domoic acid (DA) and saxitoxin (STX). Over the last 20 years, DA toxicosis has caused significant illness and mortality in marine mammals along the west coast of the USA, but has not been reported to impact marine mammals foraging in Alaskan waters...
May 2016: Harmful Algae
https://www.readbyqxmd.com/read/28072819/testing-the-efficacy-of-dna-barcodes-for-identifying-the-vascular-plants-of-canada
#10
Thomas W A Braukmann, Maria L Kuzmina, Jesse Sills, Evgeny V Zakharov, Paul D N Hebert
Their relatively slow rates of molecular evolution, as well as frequent exposure to hybridization and introgression, often make it difficult to discriminate species of vascular plants with the standard barcode markers (rbcL, matK, ITS2). Previous studies have examined these constraints in narrow geographic or taxonomic contexts, but the present investigation expands analysis to consider the performance of these gene regions in discriminating the species in local floras at sites across Canada. To test identification success, we employed a DNA barcode reference library with sequence records for 96% of the 5108 vascular plant species known from Canada, but coverage varied from 94% for rbcL to 60% for ITS2 and 39% for matK...
2017: PloS One
https://www.readbyqxmd.com/read/28070563/gut-microbiome-of-the-canadian-arctic-inuit
#11
Catherine Girard, Nicolas Tromas, Marc Amyot, B Jesse Shapiro
Diet is a major determinant of community composition in the human gut microbiome, and "traditional" diets have been associated with distinct and highly diverse communities, compared to Western diets. However, most traditional diets studied have been those of agrarians and hunter-gatherers consuming fiber-rich diets. In contrast, the Inuit of the Canadian Arctic have been consuming a traditional diet low in carbohydrates and rich in animal fats and protein for thousands of years. We hypothesized that the Inuit diet and lifestyle would be associated with a distinct microbiome...
January 2017: MSphere
https://www.readbyqxmd.com/read/28070298/community-structure-affects-trophic-ontogeny-in-a-predatory-fish
#12
Javier Sánchez-Hernández, Antti P Eloranta, Anders G Finstad, Per-Arne Amundsen
While most studies have focused on the timing and nature of ontogenetic niche shifts, information is scarce about the effects of community structure on trophic ontogeny of top predators. We investigated how community structure affects ontogenetic niche shifts (i.e., relationships between body length, trophic position, and individual dietary specialization) of a predatory fish, brown trout (Salmo trutta). We used stable isotope and stomach content analyses to test how functional characteristics of lake fish community compositions (competition and prey availability) modulate niche shifts in terms of (i) piscivorous behavior, (ii) trophic position, and (iii) individual dietary specialization...
January 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28070270/size-differences-of-arctic-marine-protists-between-two-climate-periods-using-the-paleoecological-record-to-assess-the-importance-of-within-species-trait-variation
#13
Erik A Mousing, Sofia Ribeiro, Chelsea Chisholm, Antoon Kuijpers, Matthias Moros, Marianne Ellegaard
Mean body size decreases with increasing temperature in a variety of organisms. This size-temperature relationship has generally been tested through space but rarely through time. We analyzed the sedimentary archive of dinoflagellate cysts in a sediment record taken from the West Greenland shelf and show that mean cell size decreased at both intra- and interspecific scales in a period of relatively warm temperatures, compared with a period of relatively cold temperatures. We further show that intraspecific changes accounted for more than 70% of the change in community mean size, whereas shifts in species composition only accounted for about 30% of the observed change...
January 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28069371/distribution-and-enantiomeric-profiles-of-organochlorine-pesticides-in-surface-sediments-from-the-bering-sea-chukchi-sea-and-adjacent-arctic-areas
#14
Meiqing Jin, Jie Fu, Bin Xue, Shanshan Zhou, Lina Zhang, An Li
The spatial distribution, compositional profiles, and enantiomer fractions (EFs) of organochlorine pesticides (OCPs), including hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs), and chlordanes (CHLs), in the surface sediments in the Bering Sea, Chukchi Sea and adjacent areas were investigated. The total concentrations of DDTs, HCHs and CHLs varied from 0.64 to 3.17 ng/g dw, 0.19-0.65 ng/g dw, and 0.03-0.16 ng/g dw, respectively. No significant difference was observed between the Bering Sea and Chukchi Sea for most pollutants except for trans-CHL, ΣCHLs (sum of trans- and cis-chlordane) and p,p'-DDD...
January 6, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28069276/levels-of-ingested-debris-vary-across-species-in-canadian-arctic-seabirds
#15
Florence E Poon, Jennifer F Provencher, Mark L Mallory, Birgit M Braune, Paul A Smith
Plastic debris has become a major pollutant in the world's oceans and is found in many seabird species from low to high latitudes. Here we compare levels of plastic ingestion from two surface feeders, northern fulmars (Fulmarus glacialis) and black-legged kittiwakes (Rissa tridactyla), and two pursuit diving species, thick-billed murres (Uria lomvia) and black guillemots (Cepphus grylle) in the Canadian high Arctic. This is the first report quantifying plastic ingestion in kittiwakes in this region, and as predicted, kittiwakes and fulmars had higher frequency of plastic ingestion than guillemots and murres...
January 7, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28068667/breeding-site-sampling-across-the-arctic-by-individual-males-of-a-polygynous-shorebird
#16
Bart Kempenaers, Mihai Valcu
Males of many polygynous species compete for access to fertile females without providing them with resources other than sperm and without investing in care for the offspring (male dominance polygyny). In such systems, local competition for access to females is intense and typically only a few males obtain matings, leading to strong sexual selection. Sampling multiple breeding areas could then provide a mechanism for males to increase their chances to reproduce. However, little is known about such sampling behaviour and about the spatial scale at which males compete...
January 9, 2017: Nature
https://www.readbyqxmd.com/read/28068555/activity-concentration-measurements-of-selected-radionuclides-in-seals-from-canadian-arctic
#17
Jing Chen, Weihua Zhang, Baki Sadi, Xiaowa Wang, Derek C G Muir
The activity concentrations of naturally occurring radionuclides (such as (226)Ra, (210)Pb and (210)Po) and long lived (137)Cs were measured in a total of 119 tissue samples (43 blubber, 43 liver, and 33 muscle samples) from 40 ringed seals and 4 bearded seals collected in the Arviat area of Canada during the fall of 2014. Activity concentration of (210)Po was measured in all seal liver and muscle samples individually. The average (210)Po activity concentrations were 25 ± 7.6 Bq/kg fresh weight (fw) in muscle and 211 ± 58 Bq/kg fw in liver for ringed seals, and 20 ± 6...
January 6, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28066129/a-multi-year-estimate-of-methane-fluxes-in-alaska-from-carve-atmospheric-observations
#18
Scot M Miller, Charles E Miller, Roisin Commane, Rachel Y-W Chang, Steven J Dinardo, John M Henderson, Anna Karion, Jakob Lindaas, Joe R Melton, John B Miller, Colm Sweeney, Steven C Wofsy, Anna M Michalak
Methane (CH4) fluxes from Alaska and other arctic regions may be sensitive to thawing permafrost and future climate change, but estimates of both current and future fluxes from the region are uncertain. This study estimates CH4 fluxes across Alaska for 2012-2014 using aircraft observations from the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) and a geostatistical inverse model (GIM). We find that a simple flux model based on a daily soil temperature map and a static map of wetland extent reproduces the atmospheric CH4 observations at the state-wide, multi-year scale more effectively than global-scale, state-of-the-art process-based models...
October 2016: Global Biogeochemical Cycles
https://www.readbyqxmd.com/read/28064192/leaf-anatomy-bvoc-emission-and-co2-exchange-of-arctic-plants-following-snow-addition-and-summer-warming
#19
Michelle Schollert, Minna Kivimäenpää, Anders Michelsen, Daan Blok, Riikka Rinnan
BACKGROUND AND AIMS: Climate change in the Arctic is projected to increase temperature, precipitation and snowfall. This may alter leaf anatomy and gas exchange either directly or indirectly. Our aim was to assess whether increased snow depth and warming modify leaf anatomy and affect biogenic volatile organic compound (BVOC) emissions and CO2 exchange of the widespread arctic shrubs Betula nana and Empetrum nigrum ssp. hermaphroditum METHODS: Measurements were conducted in a full-factorial field experiment in Central West Greenland, with passive summer warming by open-top chambers and snow addition using snow fences...
January 7, 2017: Annals of Botany
https://www.readbyqxmd.com/read/28063292/scale-up-considerations-for-surface-collecting-agent-assisted-in-situ-burn-crude-oil-spill-response-experiments-in-the-arctic-laboratory-to-field-scale-investigations
#20
Robin J Bullock, Srijan Aggarwal, Robert A Perkins, William Schnabel
In the event of a marine oil spill in the Arctic, government agencies, industry, and the public have a stake in the successful implementation of oil spill response. Because large spills are rare events, oil spill response techniques are often evaluated with laboratory and meso-scale experiments. The experiments must yield scalable information sufficient to understand the operability and effectiveness of a response technique under actual field conditions. Since in-situ burning augmented with surface collecting agents ("herders") is one of the few viable response options in ice infested waters, a series of oil spill response experiments were conducted in Fairbanks, Alaska, in 2014 and 2015 to evaluate the use of herders to assist in-situ burning and the role of experimental scale...
January 4, 2017: Journal of Environmental Management
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