One year later, in an article in Brain, Dib-Hajj et al., demonstrated that NaV1.7 mutants channels, from families with inherited erythromelalgia (IEM), make dorsal root ganglion (DRG, peripheral and sensory), neurons hyper excitable, thereby demonstrating the mechanistic link between these mutations and pain, thereby firmly establishing NaV1.7 gain-of-function mutations as the molecular basis for IEM. Conversely, in December 2006 a University of Cambridge team reported an SCN9A mutation that resulted in a complete lack of pain sensation in a Pakistani street performer and some of his family members. He felt no pain, walked on hot coals and stabbed himself to entertain crowds. By 2013, nearly a dozen gain-of-function mutations of NaV1.7 had been linked to IEM. The multi-decades search which identified gene SCN9A as the cause of inherited erythomelalgia is documented in a book by Stephen Waxman, Chasing Men on Fire: The Story of the Search for a Pain Gene. Classification
Primary erythromelalgia may be classified as either familial or sporadic, with the familial form inherited in an autosomal dominant manner. Both of these may be further classified as either juvenile or adult onset. The juvenile onset form occurs prior to age 20 and frequently prior to age 10. While the genetic cause of the juvenile and sporadic adult onset forms is often known, this is not the case for the adult onset familial form.In rural areas of southern China, outbreaks of erythromelalgia have occurred during winter and spring at 3-5 year intervals among secondary school students.
During British mandate over Palestine, the Irgun were among the Zionist groups labelled as terrorist organisations by the British authorities and United Nations, for violent terror attacks against Britons and Arabs. Another extremist group, the Lehi, openly declared its members as "terrorists". Historian William Cleveland stated many Jews justified any action, even terrorism, taken in the cause of the creation of a Jewish state. In 1995, Yigal Amir assassinated Israeli Prime Minister Yitzhak Rabin. For Amir, killing Rabin was an exemplary act that symbolized the fight against an illegitimate government that was prepared to cede Jewish Holy Land to the Palestinians. Perpetrators
The perpetrators of acts of terrorism can be individuals, groups, or states. According to some definitions, clandestine or semi-clandestine state actors may carry out terrorist acts outside the framework of a state of war. The most common image of terrorism is that it is carried out by small and secretive cells, highly motivated to serve a particular cause and many of the most deadly operations in recent times, such as the September 11 attacks, the London underground bombing, 2008 Mumbai attacks and the 2002 Bali bombing were planned and carried out by a close clique, composed of close friends, family members and other strong social networks. These groups benefited from the free flow of information and efficient telecommunications to succeed where others had failed.Over the years, much research has been conducted to distill a terrorist profile to explain these individuals actions through their psychology and socio-economic circumstances.