2 research outputs found
Microwave Heating of Water, Ice and Saline Solution: Molecular Dynamics Study
In order to study the heating process of water by the microwaves of 2.5-20GHz
frequencies, we have performed molecular dynamics simulations by adopting a
non-polarized water model that have fixed point charges on rigid-body
molecules. All runs are started from the equilibrated states derived from the
I ice with given density and temperature. In the presence of microwaves,
the molecules of liquid water exhibit rotational motion whose average phase is
delayed from the microwave electric field. Microwave energy is transferred to
the kinetic and inter-molecular energies of water, where one third of the
absorbed microwave energy is stored as the latter energy. The water in ice
phase is scarcely heated by microwaves because of the tight hydrogen-bonded
network of water molecules. Addition of small amount of salt to pure water
substantially increases the heating rate because of the weakening by defects in
the water network due to sloshing large-size negative ions.Comment: 21 pages, 13 figure
Molecular Chaperones and Protein Quality Control System in the Canine Model of Brain Aging and Neurodegenerative Diseases
Aged dogs naturally develop cognitive dysfunction and represent a valuable
spontaneous animal model for studying normal aging and neurodegeneration.
Elderly canines also share neuropathological hallmarks similar to those observed
in humans, especially Alzheimer’s disease-like pathology or amyotrophic
lateral sclerosis. In addition, pet dogs share similar living conditions and
diets to humans. Increasing oxidative damage, as well as alterations of the
intracellular protein quality control system, including ubiquitin-proteasome
system (UPS) and Heat shock proteins (Hsp), have been observed in the brain
of aged dogs. Thus, future researches carried out on the canine spontaneous
model may be useful to define the involvement of age-related alterations in
Hsp expression and UPS activity in the pathogenesis of neurodegenerative
diseases, as well as to perform translational antioxidant treatment/prevention
studies. The possibility to design novel therapeutic approaches, including Hspbased
therapies, may help to increase chaperone protection against proteotoxic
stress occurring in human and canine brain during aging