Results 51 to 60 of about 2,031,622 (237)

Stable isotope dilution techniques for assessing vitamin A status and bioefficacy of provitamin A carotenoids in humans. [PDF]

, 2005
Vitamin A deficiency is a major global public health problem. Among the variety of techniques that are available for assessing human vitamin A status, evaluating the provitamin A nutritional values of foodstuffs and estimating human vitamin A ...
Judy D Ribaya-Mercado, Emorn Wasantwisut, Marjorie Haskell, Sherry Tanumihardjo, Harold C Furr, Wasantwisut, Emorn, Tang, Guangwen, Penelope Nestel, Sam Newton, Guangwen Tang, Haskell, Marjorie, Ribaya-Mercado, Judy D, Najat Mokhtar, Furr, Harold C, Nestel, Penelope, Newton, Sam, Tanumihardjo, Sherry, Green, Michael H, Michael H Green, Mokhtar, Najat   +19 more
core   +1 more source

Monodeuterated Methane, an Isotopic Tool To Assess Biological Methane Metabolism Rates

mSphere, 2017
Biological methane oxidation is a globally relevant process that mediates the flux of an important greenhouse gas through both aerobic and anaerobic metabolic pathways.
Jeffrey J. Marlow, Joshua A. Steele, Wiebke Ziebis, Silvan Scheller, David Case, Linda M. Reynard, Victoria J. Orphan   +6 more
doaj   +1 more source

Burkholderiaceae Are Key Acetate Assimilators During Complete Denitrification in Acidic Cryoturbated Peat Circles of the Arctic Tundra

Frontiers in Microbiology, 2021
Cryoturbated peat circles (pH 4) in the Eastern European Tundra harbor up to 2 mM pore water nitrate and emit the greenhouse gas N2O like heavily fertilized agricultural soils in temperate regions.
Stefanie A. Hetz, Marcus A. Horn
doaj   +1 more source

Cryogenic Deformation Behavior of TiAl and Insights Into Embrittlement After High‐Temperature Exposure Combined With Secondary Ion Mass Spectroscopy of Near Surface Chemistry

Advanced Engineering Materials, EarlyView.
Near‐surface deuterium enrichment profiles for different microstructural types of TiAl after exposure at 700 °C in a heavy water‐containing environment. The deuterium levels are significantly higher than expected from natural occurrence, indicating that the heavy water dissociated during the exposure treatment and entered the specimens.
Jonathan D. H. Paul, Alexander Welle, Dirk Matthiessen, Michael Oehring, Fritz Appel, Florian Pyczak   +5 more
wiley   +1 more source

Atom Probe Tomography as an Emerging Tool for Understanding Defect‑Driven Mechanisms in HfO2‑Based Ferroelectrics

Advanced Functional Materials, EarlyView.
This Perspective highlights atom probe tomography as a powerful tool for understanding the atomic‐scale defect chemistry in HfO2‐based ferroelectrics. 3D mapping of dopants, point defects, and interface chemistry can provide new insight into defect‐driven mechanisms underpinning the ferroelectricity in the system and guide the design of more reliable ...
Kasper Hunnestad, Catherine Dubourdieu, Alexei Gruverman, Dennis Meier   +3 more
wiley   +1 more source

Comparative assessment of a restored and natural wetland using 13C-DNA SIP reveals a higher potential for methane production in the restored wetland

Applied and Environmental Microbiology
Wetlands are the largest natural source of methane (CH4), a potent greenhouse gas produced by methanogens. Methanogenesis rates are controlled by environmental factors such as redox potential, temperature, and carbon and electron acceptor availability ...
Nora Hamovit, Taniya RoyChowdhury, Denise M. Akob, Xuesong Zhang, Gregory McCarty, Stephanie Yarwood   +5 more
doaj   +1 more source

Bacterial and Archaeal Specific-Predation in the North Atlantic Basin

Frontiers in Marine Science, 2019
Stable isotope probing (SIP) was used to track prokaryotic and eukaryotic carbon uptake along a meridional transect (Long. 52°W) in the North Atlantic to assess if 13C-resource partitioning between bacteria and archaea and 13C-labeled eukaryotic ...
Lauren M. Seyler, Lauren M. Seyler, Steve Tuorto, Lora R. McGuinness, Donglai Gong, Lee J. Kerkhof   +5 more
doaj   +1 more source

Availability of Nitrite and Nitrate as Electron Acceptors Modulates Anaerobic Toluene-Degrading Communities in Aquifer Sediments

Frontiers in Microbiology, 2020
Microorganisms are essential in the degradation of environmental pollutants. Aromatic hydrocarbons, e.g., benzene, toluene, ethylbenzene, and xylene (BTEX), are common aquifer contaminants, whose degradation in situ is often limited by the availability ...
Baoli Zhu, Sebastian Friedrich, Zhe Wang, András Táncsics, Tillmann Lueders   +4 more
doaj   +1 more source

Electrochemical Pathways for Nitrate Conversion to Ammonia: From Environmental Challenges to Ammonia Economy

Advanced Functional Materials, EarlyView.
This perspective presents recent advances in electrocatalytic nitrate reduction, focusing on reaction mechanisms, catalyst design, and electrolyzer configurations. Key challenges in selectivity, stability, and practical wastewater treatment are highlighted, while future directions for advancing sustainable ammonia synthesis and nitrate remediation are ...
Xintong Li, Yunpeng Zuo, Xiaoran Zhang, Jieqiong Shan, Kenneth Mei Yee Leung, Bin Liu, Peter Strasser, Adrian Fisher, Zonglong Zhu, Xin Wang   +9 more
wiley   +1 more source

Elevated and atmospheric‐level methane consumption by soil methanotrophs of three grasslands in China

Grassland Research, 2023
Background Methane (CH4) oxidation driven by soil aerobic methanotrophs demonstrates the capacity of grassland as a CH4 sink. Methods In this study, we compared the oxidation characteristics of atmospheric‐level and elevated concentration (10%) CH4 in a ...
Yufang Wang, Yuanfeng Cai, Fujiang Hou, Saman Bowatte, Zhongjun Jia   +4 more
doaj   +1 more source