Nutrient intake related to one-carbon metabolism, including folate, vitamin B2, and vitamin B12, was assessed using a food frequency questionnaire developed for Mexican populations. Multivariable linear regression was used to estimate the association between BMI and the distribution of urinary arsenic ...
The nature of the mass (e.g. nominal mass or monoisotopic mass) recorded by a mass spectrometer depends on the characteristics of the used instrument, especially on the mass resolution and mass resolving power. With low mass resolving power, only peaks differing by one mass unit can be separa...
FA cross-linking of proteins is assumed to involve the formation of a methylene bridge between two proximal amino acids (R1-CH2-R2)7,8. However, direct evidence to support this mechanism is sparse. In terms of mass, the methylene bridge adds 12 Da (one carbon atom) to the total mass...
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and it is the number and arrangement of the electrons in their orbiting shells that determines how one atom interacts with another. The key shell is the outermost one, called thevalenceshell. If this outermost shell is complete, or filled with the maximum number of electrons for that shell, ...
(Figure 2) that are connected by flows of material and energy. Any compartment could represent a biotic or abiotic component: a fish, a school of fish, a forest, or a pool of carbon. Because of mass balance, over time the amount of any element in any one of these compartments could ...
Structural Design of Cathodes for Li‐S Batteries Battery technologies involving Li-S chemistries have been touted as one of the most promising next generation systems. The theoretical capacity of sulfur i... MA Pope,IA Aksay - 《Advanced Energy Materials》 被引量: 67发表: 2015年 Three-Dimensi...
and sampled after thawing in April and October 2007.Rates of litter decomposition and releases of carbon and nutrients were measured in different soil depths and forest stands during a freezing and following season.Over one freeze-thaw season,(19.4±2.0)% and(21.5±3.5)% leaf litters were ...
“reverse phase,” a hydrophobic carbon chain column with progressively less polar aqueous-organic solvent mixtures. Innormal phase chromatography, the more polar compounds elute last as the polarity of the solvent (“mobile phase”) increases, whereas inreverse phase HPLCthe more polar com...
This indicates that one of the first fragmentation events in the case of NTPs is the loss of the γ-phosphate, which is consistent with the chemical lability of the β,γ-pyrophosphate bond33. Consequently, the fragmentation of NTPs is expected to occur through the same pathways as those ...