"It's more than just a giant bag of serotonin or dopamine whose concentrations sometimes are too low or too high.
A combined gas chromatograph mass spectrometer can rapidly identify the individual components of a chemical mixture whose concentrations may be no greater than a few parts per billion.
With this year's record following records in 1996 and 1998, some atmospheric scientists are beginning to express surprise at the persistence of the phenomenon, which is caused largely by reactions between ozone and a group of synthetic chemicals that have been banned and whose concentrations are starting to decline in the air.
The title of his new book, "Ordinary Resurrections: Children in the Years of Hope," has the same evocation of faith as "Amazing Grace" and the same narrative focus, Mott Haven, an area whose concentrations of pediatric and maternal AIDS are among the nation's highest.
Fortunately, then, evolution has equipped mammals with the ability to detect by smell chemicals whose concentrations vary with differences in the MHC of the producer.That means people are able to sniff out suitable MHC genomes in prospective partners.
Glycerol, furfural and HMF, whose concentrations were below the detection limit, are not discussed.
Some inorganic compounds are dissolved, among which manganese, whose concentrations can reach 1 μg L−1.
Shown are 9 of 18 cytokines and chemokines whose concentrations in the muscles changed after injury in RNF13-/ mice.
Effects of these three factors and identity of the metabolites whose concentrations changed because of them were investigated.
The ions that were analysed for, and whose concentrations are not very sensitive to, pyrite oxidation reactions include Na+ and Ca 2+.
Here, known measure of adsorbent was completely mixed with 50 mL of individual Pb2+ solutions, whose concentrations and pHs were beforehand known.
