These are also the first five sporadic groups to have been described, defined as 
  
    
      
        
          
            M
          
          
            n
          
        
      
    
    {\displaystyle \mathrm {M} _{n}}
   multiply transitive permutation groups on 
  
    
      
        n
      
    
    {\displaystyle n}
   objects, with 
  
    
      
        n
      
    
    {\displaystyle n}
   ∈ {11, 12, 22, 23, 24}.
Dexmedetomidine, sold under the trade name Precedex among others, is a medication used for sedation. It is also used to treat acute agitation associated with schizophrenia or bipolar I or II disorder.Similar to clonidine, it is a sympatholytic drug that acts as an agonist of α2-adrenergic receptors in certain parts of the brain. Veterinarians use dexmedetomidine for similar purposes in treating cats, dogs, and horses. It was developed by Orion Pharma. Medical uses
Intensive care unit sedation
Studies suggest dexmedetomidine for sedation in mechanically ventilated adults may reduce time to extubation and ICU stay.Compared with other sedatives, some studies suggest dexmedetomidine may be associated with less delirium. However, this finding is not consistent across multiple studies. At the very least, when aggregating many study results together, use of dexmedetomidine appears to be associated with less neurocognitive dysfunction compared to other sedatives. Whether this observation has a beneficial psychological impact is unclear. From an economic perspective, dexmedetomidine is associated with lower ICU costs, largely due to a shorter time to extubation. Procedural sedation
Dexmedetomidine can also be used for procedural sedation such as during colonoscopy. It can be used as an adjunct with other sedatives like benzodiazepines, opioids, and propofol to enhance sedation and help maintain hemodynamic stability by decreasing the requirement of other sedatives. Dexmedetomidine is also used for procedural sedation in children.It can be used for sedation required for awake fibreoptic nasal intubation in patients with a difficult airway.