Network protocols that use aggressive retransmissions to compensate for packet loss due to congestion can increase congestion, even after the initial load has been reduced to a level that would not normally have induced network congestion. Such networks exhibit two stable states under the same level of load.
Beta blocker. Beta blocker, also written Î²-blocker, is a class of medications that are particularly used to manage cardiac arrhythmias, and to protect the heart from a second heart attack (myocardial infarction) after a first heart attack (secondary prevention).
Beta-blockers are drugs commonly used in the treatment of high blood pressure and congestive heart failure. They work primarily by blocking the neurotransmitters norepinephrine and epinephrine (adrenaline) from binding to beta receptors, thereby dilating blood vessels, which reduces your heart rate and blood pressure.