The smallest storm on record is Tropical Storm Marco (2008), which generated tropical storm-force winds only 37 km (23 mi) in diameter. Movement
The movement of a tropical cyclone (i.e. its "track") is typically approximated as the sum of two terms: "steering" by the background environmental wind and "beta drift". Some tropical cyclones can move across large distances, such as Hurricane John, the longest-lasting tropical cyclone on record, which traveled 13,280 km (8,250 mi), the longest track of any Northern Hemisphere tropical cyclone, over its 31-day lifespan in 1994. Environmental steering
Environmental steering is the primary influence on the motion of tropical cyclones. It represents the movement of the storm due to prevailing winds and other wider environmental conditions, similar to "leaves carried along by a stream".Physically, the winds, or flow field, in the vicinity of a tropical cyclone may be treated as having two parts: the flow associated with the storm itself, and the large-scale background flow of the environment. Tropical cyclones can be treated as local maxima of vorticity suspended within the large-scale background flow of the environment. In this way, tropical cyclone motion may be represented to first-order as advection of the storm by the local environmental flow. This environmental flow is termed the "steering flow" and is the dominant influence on tropical cyclone motion. The strength and direction of the steering flow can be approximated as a vertical integration of the winds blowing horizontally in the cyclones vicinity, weighted by the altitude at which those winds are occurring.
Clofazimine, sold under the brand name Lamprene, is a medication used together with rifampicin and dapsone to treat leprosy. It is specifically used for multibacillary (MB) leprosy and erythema nodosum leprosum. Evidence is insufficient to support its use in other conditions though a retrospective study found it 95% effective in the treatment of Mycobacterium avium complex (MAC) when administered with a macrolide and ethambutol, as well as the drugs amikacin and clarithromycin. However, in the United States, clofazimine is considered an orphan drug, is unavailable in pharmacies, and its use in the treatment of MAC is overseen by the Food and Drug Administration. It is taken orally.Common side effects include abdominal pain, diarrhea, itchiness, dry skin, and change in skin color. It can also cause swelling of the lining of the gastrointestinal tract, increased blood sugar, and sensitivity to the sun. It is unclear if use during pregnancy is safe. Clofazimine is a phenazine dye and is believed to work by interfering with DNA.Clofazimine was discovered in the 1950s at Trinity College, Dublin, and approved for medical use in the United States in 1986. It is on the World Health Organizations List of Essential Medicines. In the United States it is not available commercially but can be obtained from the US Department of Health and Human Services. Medical uses
The primary use of clofazimine is for the treatment of leprosy.