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https://www.readbyqxmd.com/read/28531951/identifying-and-quantifying-geochemical-and-mixing-processes-in-the-matanza-riachuelo-aquifer-system-argentina
#1
S Armengol, M Manzano, S A Bea, S Martínez
The Matanza-Riachuelo River Basin, in the Northeast of the Buenos Aires Province, is one of the most industrialized and populated region in Argentina and it is worldwide known for its alarming environmental degradation. In order to prevent further damages, the aquifer system, which consists of two overlaid aquifers, is being monitored from 2008 by the river basin authority, Autoridad de la Cuenca Matanza-Riachuelo. The groundwater chemical baseline has been established in a previous paper (Zabala et al., 2016), and this one is devoted to the identification of the main physical and hydrogeochemical processes that control groundwater chemistry and its areal distribution...
May 17, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28531830/isotope-coded-derivatization-based-lc-esi-ms-ms-methods-using-a-pair-of-novel-reagents-for-quantification-of-hydroxycinnamic-acids-and-hydroxybenzoic-acids-in-fermented-brown-rice-product
#2
Shoujiro Ogawa, Kiriko Takafuji, Sumi Tsubuku, Yukiko Horie, Shigeo Ikegawa, Tatsuya Higashi
Hydroxycinnamic acids (HCAs) and hydroxybenzoic acids (HBAs) are antioxidant phytochemicals found in rice and effective for the prevention of human diseases including cancer. FBRA, which is a functional food manufactured by fermenting brown rice and rice bran with Aspergillus oryzae, has been demonstrated to have chemopreventive effects against carcinogenesis in various organs. In this study, we developed methods for the relative and absolute quantification of ferulic acid, sinapic acid, caffeic acid, protocatechuic acid and syringic acid in the FBRA and raw material (RM; unfermented brown rice and rice bran) samples by LC/ESI-MS/MS combined with derivatization using a newly developed reagent, N-(2-aminoethyl)-4-(diethylamino)benzamide (ADB) and its deuterium-coded analog, d-ADB...
May 2, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28531221/human-paleodiet-and-animal-utilization-strategies-during-the-bronze-age-in-northwest-yunnan-province-southwest-china
#3
Lele Ren, Xin Li, Lihong Kang, Katherine Brunson, Honggao Liu, Weimiao Dong, Haiming Li, Rui Min, Xu Liu, Guanghui Dong
Reconstructing ancient diets and the use of animals and plants augment our understanding of how humans adapted to different environments. Yunnan Province in southwest China is ecologically and environmentally diverse. During the Neolithic and Bronze Age periods, this region was occupied by a variety of local culture groups with diverse subsistence systems and material culture. In this paper, we obtained carbon (δ13C) and nitrogen (δ15N) isotopic ratios from human and faunal remains in order to reconstruct human paleodiets and strategies for animal exploitation at the Bronze Age site of Shilinggang (ca...
2017: PloS One
https://www.readbyqxmd.com/read/28530825/effect-of-wood-aging-on-wine-mineral-composition-and-87sr-86sr-isotopic-ratio
#4
Ayse Deniz Kaya, Raúl Bruno de Sousa, António Sérgio Curvelo-Garcia, Jorge Manuel Ricardo-da-Silva, Sofia Catarino
Evolution of mineral composition and wine strontium isotopic ratio 87Sr/86Sr (Sr IR) during wood aging were investigated. A red wine was aged in stainless steel tanks with French oak staves (Quercus sessiliflora Salisb.), with three industrial scale replicates. Sampling was carried out after 30, 60 and 90 days of aging, and the wines evaluated in terms of general analysis, phenolic composition, total polysaccharides, multi-element composition and Sr IR. Li, Be, Mg, Al, Sc, Ti, V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Sb, Cs, Ba, Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb, Lu, Tl, Pb elements and 87Sr/86Sr were determined by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS), Na, K, Ca and Fe by flame atomic absorption spectrometry (FAAS)...
May 22, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28529500/co-existence-of-methanogenesis-and-sulfate-reduction-with-common-substrates-in-sulfate-rich-estuarine-sediments
#5
Michal Sela-Adler, Zeev Ronen, Barak Herut, Gilad Antler, Hanni Vigderovich, Werner Eckert, Orit Sivan
The competition between sulfate reducing bacteria and methanogens over common substrates has been proposed as a critical control for methane production. In this study, we examined the co-existence of methanogenesis and sulfate reduction with shared substrates over a large range of sulfate concentrations and rates of sulfate reduction in estuarine systems, where these processes are the key terminal sink for organic carbon. Incubation experiments were carried out with sediment samples from the sulfate-methane transition zone of the Yarqon (Israel) estuary with different substrates and inhibitors along a sulfate concentrations gradient from 1 to 10 mM...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28528907/widespread-biological-response-to-rapid-warming-on-the-antarctic-peninsula
#6
Matthew J Amesbury, Thomas P Roland, Jessica Royles, Dominic A Hodgson, Peter Convey, Howard Griffiths, Dan J Charman
Recent climate change on the Antarctic Peninsula is well documented [1-5], with warming, alongside increases in precipitation, wind strength, and melt season length [1, 6, 7], driving environmental change [8, 9]. However, meteorological records mostly began in the 1950s, and paleoenvironmental datasets that provide a longer-term context to recent climate change are limited in number and often from single sites [7] and/or discontinuous in time [10, 11]. Here we use moss bank cores from a 600-km transect from Green Island (65...
May 17, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28528413/dissolved-platinum-concentrations-in-coastal-seawater-boso-to-sanriku-areas-japan
#7
Asami Suzuki Mashio, Hajime Obata, Toshitaka Gamo
Platinum, one of the rarest elements in the earth's crust, is now widely used in a range of products, such as catalytic converters in automobiles and anticancer drugs. Increasing use and dispersal of platinum has the potential to affect aquatic environments. Platinum concentrations in open ocean seawater have been found to be very low (approximately 0.2 pmol/L); however, Pt distributions and biogeochemical cycles in coastal areas are unknown. In this study, we investigated Pt concentrations in coastal waters between the Boso and Sanriku areas, Japan, after the 2011 tsunami...
May 20, 2017: Archives of Environmental Contamination and Toxicology
https://www.readbyqxmd.com/read/28528408/the-glaucous-winged-gull-larus-glaucescens-as-an-indicator-of-chemical-contaminants-in-the-canadian-pacific-marine-environment-evidence-from-stable-isotopes
#8
M L Davis, J E Elliott, T D Williams
The Glaucous-winged gull (Larus glaucescens) has been selected by Environment Canada as a marine indicator species for long-term monitoring of persistent contaminants in the Canadian Pacific. However, the indicator value of this species depends on its trophic level and proportion of marine prey in its diet. Eggs, used as the monitoring medium, are produced entirely from maternal resources and knowledge of adult diet before and during egg production is critical to interpreting contaminant levels. Due to a lack of recent and reliable dietary ecology work, we examined the diet of breeding Glaucous-winged gulls through carbon (δ(13)C) and nitrogen (δ(15)N) stable isotope analysis at three colonies on the Pacific coast...
May 20, 2017: Archives of Environmental Contamination and Toxicology
https://www.readbyqxmd.com/read/28528262/stable-isotope-tracing-of-ni-and-cu-pollution-in-north-east-norway-potentials-and-drawbacks
#9
Hana Šillerová, Vladislav Chrastný, Martina Vítková, Anna Francová, Jan Jehlička, Marissa R Gutsch, Jana Kocourková, Paul E Aspholm, Lars O Nilsson, Tore F Berglen, Henning K B Jensen, Michael Komárek
The use of Ni and Cu isotopes for tracing contamination sources in the environment remains a challenging task due to the limited information about the influence of various biogeochemical processes influencing stable isotope fractionation. This work focuses on a relatively simple system in north-east Norway with two possible endmembers (smelter-bedrock) and various environmental samples (snow, soil, lichens, PM10). In general, the whole area is enriched in heavy Ni and Cu isotopes highlighting the impact of the smelting activity...
May 18, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28528213/optimal-electrostatic-interactions-between-substrate-and-protein-are-essential-for-radical-chemistry-in-ornithine-4-5-aminomutase
#10
Caitlyn Makins, Douglas A Whitelaw, Michael McGregor, Alix Petit, Robert G Mothersole, Kathleen E Prosser, Kirsten R Wolthers
Ornithine 4,5-aminomutase (OAM) from Clostridium sticklandii is an adenosylcobalamin (AdoCbl) and pyridoxal 5'-phosphate (PLP)-dependent enzyme that catalyzes a 1,2-amino shift, interconverting D-ornithine and 2S, 4R-diaminopentanoate. The reaction occurs via a radical-based mechanism whereby a PLP-bound substrate radical undergoes intramolecular isomerization via an azacyclopropylcarbinyl radical intermediate. Herein, we investigated the catalytic role of active site residues that form non-covalent interactions with PLP and/or substrate, D-ornithine...
May 17, 2017: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/28528142/per-and-polyfluoroalkyl-substances-pfas-in-american-red-cross-adult-blood-donors-2000-2015
#11
Geary W Olsen, David C Mair, Cleston C Lange, Laura M Harrington, Timothy R Church, Corinne L Goldberg, Ross M Herron, Hank Hanna, John B Nobiletti, Jorge A Rios, William K Reagen, Carol A Ley
In 2015, thirteen per- and polyfluoroalkyl substances (PFAS), including perfluorohexanesulfonate (PFHxS), perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), and perfluorodecanoate (PFDA) were analyzed in human plasma that was collected from a total of 616 American Red Cross male and female blood donors (ages 20-69) at 6 regional blood collection centers. Plasma samples were analyzed using a validated solvent precipitation-isotope dilution direction-liquid chromatography tandem mass spectrometry method...
May 17, 2017: Environmental Research
https://www.readbyqxmd.com/read/28527806/endogenous-synthesis-of-milk-oleic-acid-in-dairy-ewes-in-vivo-measurement-using-13-c-labeled-stearic-acid
#12
P G Toral, P Frutos, D Carreño, G Hervás
The use of stable isotopes is a reliable and risk-free alternative to radioactive tracers for directly examining in vivo fatty acid (FA) metabolism. However, very limited information is available in ruminants, and none is available in sheep. Therefore, we conducted an experiment in dairy ewes to determine, for the first time in this species, the uptake, Δ(9)-desaturation, and secretion of (13)C-labeled stearic acid (SA) into milk with the aim of measuring in vivo endogenous synthesis of milk oleic acid (OA) and stearoyl-CoA desaturase activity...
May 17, 2017: Journal of Dairy Science
https://www.readbyqxmd.com/read/28527792/3d-cmro2-mapping-in-human-brain-with-direct-17-o-mri-comparison-of-conventional-and-proton-constrained-reconstructions
#13
Dmitry Kurzhunov, Robert Borowiak, Marco Reisert, Axel Joachim Krafft, Ali Caglar Özen, Michael Bock
Oxygen metabolism is altered in brain tumor regions and is quantified by the cerebral metabolic rate of oxygen consumption (CMRO2). Direct dynamic (17)O MRI with inhalation of isotopically enriched (17)O2 gas can be used to quantify CMRO2; however, pixel-wise CMRO2 quantification in human brain is challenging due to low natural abundance of (17)O isotope and, thus, the low signal-to-noise ratio (SNR) of (17)O MR images. To test the feasibility CMRO2 mapping at a clinical 3 T MRI system, a new iterative reconstruction was proposed, which uses the edge information contained in a co-registered (1)H gradient image to construct a non-homogeneous anisotropic diffusion (AD) filter...
May 17, 2017: NeuroImage
https://www.readbyqxmd.com/read/28527743/distribution-and-sources-of-organic-carbon-nitrogen-and-their-isotopes-in-surface-sediments-from-the-largest-mariculture-zone-of-the-eastern-guangdong-coast-south-china
#14
Yang-Guang Gu, Jun Ouyang, Jia-Jia Ning, Zeng-Huan Wang
China is the world's largest mariculture producer. However, there is limited detailed information on organic matter distribution generated by mariculture in China. This study assessed the total organic carbon (TOC), total nitrogen (TN), and isotopic composition (δ(13)C and δ(15)N) in surface sediments from Zhelin Bay in South China. TOC, TN, δ(13)C and δ(15)N ranged from 0.46-1.23%, 0.08-0.20%, -22.07 to -21.13‰ and 5.28-7.14‰, respectively, and followed similar spatial patterns. The C/N ratio coupled with isotopic composition (δ(13)C and δ(15)N), indicates that the TOC originated from both terrestrial and marine sources...
May 17, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28527646/high-dose-amino-acid-administration-achieves-an-anabolic-response-in-type-2-diabetic-patients-that-is-independent-of-glycaemic-control-a-randomized-clinical-trial
#15
Chelsia Gillis, Patricia S Roque, Jürgen Bläss, Albert Urwyler, Harald Schepperle, Guido Kunz, Thomas Peters, Thomas Schricker, Linda Wykes, Andrea Kopp Lugli
BACKGROUND & AIMS: Surgical stress provokes protein catabolism and hyperglycaemia that is enhanced in patients with type 2 diabetes (T2DM), and increases perioperative morbidity. This study hypothesized that perioperative administration of high dose intravenous (IV) amino acids (AA) will augment protein balance in T2DM patients receiving tight plasma glucose control via continuous IV insulin compared to standard plasma glucose control via subcutaneous (SC) insulin sliding scale. METHODS: Eighteen patients with well-controlled T2DM (HbA1C% < 7...
May 3, 2017: Clinical Nutrition: Official Journal of the European Society of Parenteral and Enteral Nutrition
https://www.readbyqxmd.com/read/28527183/analytical-methods-in-tracing-honey-authenticity
#16
Jelena Trifković, Filip Andrić, Petar Ristivojević, Etil Guzelmeric, Erdem Yesilada
Honey is a precious natural product that is marketed with a wide range of nutritional and medicinal properties. However, it is also a product subjected to frequent adulteration through mislabeling and mixing with cheaper and lower-quality honeys and various sugar syrups. In that sense, honey authentication regarding its genuine botanical and geographical origins, as well as the detection of any adulteration, is essential in order to protect consumer health and to avoid competition that could create a destabilized market...
May 19, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28527001/the-relative-abundance-of-dimethylsulfoniopropionate-dmsp-among-other-zwitterions-in-branching-coral-at-heron-island-southern-great-barrier-reef
#17
Hilton B Swan, Elisabeth S M Deschaseaux, Graham B Jones, Bradley D Eyre
Dimethylsulfoniopropionate (DMSP) and eleven other target zwitterions were quantified in the branch tips of six Acropora species and Stylophora pistillata hard coral growing on the reef flat surrounding Heron Island in the southern Great Barrier Reef (GBR), Australia. Hydrophilic interaction liquid chromatography mass spectrometry (HILIC-MS) was used for sample analysis with isotope dilution MS applied to quantify DMSP. The concentration of DMSP was ten times greater in A. aspera than A. valida, with this difference being maintained throughout the spring, summer and winter seasons...
May 20, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28526853/response-of-coral-calcification-and-calcifying-fluid-composition-to-thermally-induced-bleaching-stress
#18
J P D'Olivo, M T McCulloch
Severe, global-scale thermal stress events like those of 1998 and 2016, are becoming more frequent and intense, potentially compromising the future of coral reefs. Here we report the effects of the 1998 bleaching event on coral calcification as well as the composition of the calcifying fluid (cf) from which corals precipitate their calcium carbonate skeletons. This was investigated by using the Sr/Ca, Li/Mg (temperature), and boron isotopes (δ(11)B) and B/Ca (carbonate chemistry) proxies in a Porites sp. coral...
May 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28526526/nuclear-weapons-produced-236-u-239-pu-and-240-pu-archived-in-a-porites-lutea-coral-from-enewetak-atoll
#19
M B Froehlich, S G Tims, S J Fallon, A Wallner, L K Fifield
A slice from a Porites Lutea coral core collected inside the Enewetak Atoll lagoon, within 15 km of all major nuclear tests conducted at the atoll, was analysed for (236)U, (239)Pu and (240)Pu over the time interval 1952-1964 using a higher time resolution than previously reported for a parallel slice from the same core. In addition two sediment samples from the Koa and Oak craters were analysed. The strong peaks in the concentrations of (236)U and (239)Pu in the testing years are confirmed to be considerably wider than the flushing time of the lagoon...
May 16, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28524870/autotrophic-and-heterotrophic-acquisition-of-carbon-and-nitrogen-by-a-mixotrophic-chrysophyte-established-through-stable-isotope-analysis
#20
Ramon Terrado, Alexis L Pasulka, Alle A-Y Lie, Victoria J Orphan, Karla B Heidelberg, David A Caron
Collectively, phagotrophic algae (mixotrophs) form a functional continuum of nutritional modes between autotrophy and heterotrophy, but the specific physiological benefits of mixotrophic nutrition differ among taxa. Ochromonas spp. are ubiquitous chrysophytes that exhibit high nutritional flexibility, although most species generally fall towards the heterotrophic end of the mixotrophy spectrum. We assessed the sources of carbon and nitrogen in Ochromonas sp. strain BG-1 growing mixotrophically via short-term stable isotope probing...
May 19, 2017: ISME Journal
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