operates in classical or helium-free mode. vacuum pump supplied separately. more... autosorb- isa the new autosorb- isa provides six ports for independent analysis of to samples. dedicated pressure transducers, dewar flasks, coolant level sensors, and po cells allow independent and simultaneous operation...
. many biological structures, such as skin, eyes, fur and hair contain pigments (such as melanin). animal skin coloration is often achieved with specialized cells called chromatophores, which in animals such as the octopus and chameleon can be controlled to vary the animal's colour. many conditions affect...
likely to experience premature graying (before age ) than nonsmokers. another study , in the journal of the american academy of dermatology, linked smoking to premature graying in young men. the mechanism, similar to one proposed for stress, is that free radicals (produced by smoking) may damage the cells...
or exhaustive exercise, such as running a marathon, significantly increases oxidative damage. the body adapts to exercise over time by boosting its own antioxidant activity, thus decreasing oxidative damage. free radicals are good in some ways. some are involved in immunity, communication between cells...
this essential micronutrient affects the development and maintenance of red blood cells, nerve cells, and normal myelination (covering) of nerve cells. it also aids in the production of dna, rna, and neurotransmitters. what are the signs of a vitamin b deficiency?...