Physics of Neutron Star Crusts

The physics of neutron star crusts is vast, involving many different research fields, from nuclear and condensed matter physics to general relativity. This review summarizes the progress, which has been achieved over the last few years, in modeling neutron star crusts, both at the microscopic and macroscopic levels. The confrontation of these theoretical models with observations is also briefly discussed.Comment: 182 pages, published version available at <http://www.livingreviews.org/lrr-2008-10

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Polineuropatia do paciente crítico: registro de caso Critical illness polyneuropathy: case report

A polineuropatia do paciente crítico é de natureza axonal, aguda e de predomínio motor, desenvolvendo-se em pacientes sépticos ou com falência de múltiplos órgãos que geralmente necessitam de ventilação mecânica em unidade de tratamento intensivo. Seu diagnóstico é corroborado por achados eletroneuromiográficos e, geralmente, a evolução é satisfatória e rápida. Relatamos o caso de uma paciente de 35 anos que, após internação em unidade de tratamento intensivo devido a septicemia e retirada de feto morto, desenvolveu tetraparesia com melhora importante em quatro meses. A eletroneuromiografia mostrou diminuição de amplitudes de potenciais sensitivos e motores, ondas positivas e fibrilações. A biópsia de nervo sural evidenciou neuropatia axono-mielínica em atividade. Estando esses achados condizentes com os da literatura, acreditamos tratar-se de caso de polineuropatia do paciente crítico.<br>The critical illness polyneuropathy has an acute onset and an axonal predominantly motor nature. It occurs in sepsis or in multiple organ failure usually requiring mechanical ventilation in critical care units. Electroneuromyography corroborates the diagnosis. Usually it courses satisfactorily. We report on a 35-year-old female patient who, after a permanence in a critical care unit due to sepsis and removal of a dead phetus, developed tetraparesis. She had an important improvement in four months. Electromyography showed reduction of amplitude of motor and sensory action potentials, positive waves and fibrillations. The sural nerve biopsy showed axon-myelinic neuropathy. These findings are consistent with those in literature and we believe they support the diagnosis of critical illness neuropathy