Derailleur gears several standards in use, and in each the product of the derailleur's actuation ratio and the length of cable pulled must equal the pitch of the rear sprockets. The following standards exist. Some rear derailleurs, especially for mountain bikes, incorporate a clutch to keep the lower length of chain in sufficient tension to prevent the chain from striking the bottom of the chain stay, called "chain slap", and which can damage the chain stay. Clutches are also helpful in preventing the chain from derailing from the chain ring on systems without a front derailleur. The front derailleur only has to
On the Origin of the "Influencing Machine" in Schizophrenia On the Origin of the "Influencing Machine" in Schizophrenia "On the Origin of the 'Influencing Machine' in Schizophrenia" is an article written by psychoanalyst Viktor Tausk. It was first published in 1919 in the journal "Internationale Zeitschrift für Psychoanalyse" and then, after translation into English by Dorian Feigenbaum, in the "Psychoanalytic Quarterly" in 1933. The paper describes Tausk's observations and psychoanalytic interpretation of paranoid delusion that occurs in patients diagnosed with schizophrenia. The delusion often involves their being influenced by a "diabolical machine", just outside the technical understanding of the victim, that influences them from afar. It is typically believed