Trauma and BMI Mortality.

PURPOSE OF REVIEW: Obesity has been recognized as an impactful comorbid condition. It has been demonstrated to be an independent risk factor for morbidity and mortality following trauma. RECENT FINDINGS: Multiple studies and reviews have strongly suggested obesity to be associated with increased risk for post-injury morbidity and mortality. As obesity is associated with a pro-inflammatory state, it has been suggested to negatively affect the respiratory, cardiovascular, coagulation, and renal systems and the ability and manner in which an obese patient heals. As obesity continues to rise at alarming rates in the USA, this population of patients requires special consideration and continued research is underway to delineate relationships between obesity, trauma, and outcomes in an effort to improve overall care.

Temperature-dependent phase behavior of polyelectrolyte-mixed micelle systems.

The effect of temperature on the phase behavior of a polycation-anionic/nonionic mixed micelle system, poly(dimethyldiallylammonium chloride)-sodium dodecylsulfate/Triton X-100, was studied over a wide range of surfactant compositions, ionic strengths, and polycation molecular weights using turbidimetry and dynamic light scattering. Soluble complexes become biphasic upon heating through either liquid-liquid (coacervation) or liquid-solid (precipitation) separation. The biphasic boundary comprises two regions: a coacervate domain exhibiting a lower critical solution temperature and a second superimposed domain in which either solids or very dense and viscous fluids are formed upon heating. The position of the first region is symmetrically centered around conditions corresponding to charge neutralization of complexes and their aggregates at incipient phase separation. The second region, observed at high micelle charge, corresponds to the collapse of polycation onto micelle surfaces and expulsion of counterions and can produce either dense coacervate or precipitate. The two regions exhibit different dependences on ionic strength, polyelectrolyte molecular weight, and concentration, from which inferences about the mechanisms of phase separation may be drawn. Preliminary observations of the dense liquid phases isolated after coacervation disclose a number of interesting optical and rheological properties, possibly arising from shear-induced phase separation.