Gynecomastia is an increase in the size of the mammary gland in men. The condition can occur in one or both breasts. It starts as a small mass under the nipple, which can be sensitive. One breast can be bigger than the other. Its cause is an imbalance between the stimulatory effects of estrogen (female sex hormones) and the inhibitory effects of androgens (male sex hormones) in the breast tissue, when the first ones increase, or the second ones descend.
Gynecomastia is a problem relatively common in the population, and there are three prevalence peaks throughout life:
Newborns: Between 60 and 90% of newborns have gynecomastia, produced by the passage of maternal estrogens through the placenta. It is a transient gynecomastia that disappears in about 2-3 weeks.
Puberty: Gynecomastia in puberty affects mainly young people aged between 10 and 14 years, and is due to the transient and physiological increase in estrogen that occurs at this age.
Elderly: Is due to an increase in fatty tissue with a greater peripheral aromatization ( a process that occurs in adipose tissue and that involves the conversion of androgens into estrogens), a decrease in the production of testosterone by the testes and the use of drugs.
Any cells of the human body, except the cells of a placenta.
Carbon capture and sequestration
While it's not a power generation technology, carbon capture and sequestration—technologies that allow for the scrubbing of carbon from power plants for storage in underground reservoirs—may finally be coming of age after years of trial and error.
Technology pilot demonstrations at coal-based power plants in places like Australia and the U.S. have sparked new interest in the technology.
The hope is, it could become an enabler for other technologies, such as biomass or algae-based biofuels that produce carbon emissions. That's because organic fuels pull carbon from the atmosphere before converting it to fuel.
Ocean floor is much more denser than the continental crust that's why the oceanic crust subduct rather than the continental crust