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).
1 Beta-blockers-can be used to slow down your heart rate, and improve blood flow through your body. 2  You may take this drug if you have been diagnosed with irregular heartbeats, or high blood pressure. 3  Some examples of this medication may include: Metoprolol (Lopressor), propanolol (Inderal), and atenolol (Tenormin).