Clinical predictors of abnormal chest CT scan findings following blunt chest trauma: A cross-sectional study

Purpose:Some surgeons believe that chest computed tomography(CT)scan should be used more prudently in management of blunt chest trauma patients.This study aimed to evaluate the clinical predictors of abnormal chest CT scan findings in trauma patients.Methods:This cross-sectional study was conducted on blunt chest trauma patients aged18 years who were referred to the emergency departments of two educational hospitals and underwent chest CT scan.These patients were enrolled in the study using a non-probability sampling method.The exclusion criteria included:class III or IV hemodynamic shock,need for immediate surgical or neurosurgical interventions,penetrating trauma,lack of required information,and pregnancy.Demographic factors,accident details,trauma mechanism,vital signs,and level of consciousness in predicting abnormal chest CT scan findings were evaluated.Analysis was performed using IBM SPSS statistics 21.Results:A total of 977 patients(male 51.5%,female 48.5%)with the mean age of(41.71±14.24)years,range 18e88 years were studied;34.2% of them with high energy trauma mechanism.With 334(34.2%)patients had abnormal findings on chest X-ray(CXR)and 332(34.0%)cases had an abnormal findings on chest CT scan(agreement rate was 99.4%).There was a significant correlation between male gender(p<0.0001),GCS<15(p<0.0001),high energy trauma mechanism(p<0.0001),unstable hemodynamics(p<0.01),and clinical signs and symptoms(p<0.0001)with chest CT findings.Chest wall deformity(odds=8;p<0.0001),generalized tenderness(odds=6.6,p<0.0001),and decreased cardiac sound(odds=3.8,p<0.0001)were the important and independent clinical predictors of abnormal chest CT scan findings.Conclusion:Based on the findings,chest wall deformity,generalized tenderness,decreased cardiac sound,distracting pain,chest wall tenderness,high energy trauma mechanism,male gender,respiratory rate>20 breathes/min,decreased pulmonary sound,and chest wall crepitation were independent clinical predictors of abnormal chest CT scan findings following blunt trauma.

Reliability assessment of networks-on-chip based on analytical models

As technology scales down, the reliability issues are becoming more crucial, especially for networks-on-chip (NoCs) that provide the communication requirements of multi-processor systems-on-chip. Reliability evaluation based on analytical models is a precise method for dependability analysis before and after designing the fault-tolerant systems. In this paper, we accurately formulate the inherent reliability and vulnerability of some popular NoC architectures against permanent faults, also depending on the employed routing algorithm and traffic model. Based on this analysis, effects of failures in the links, switches and network interfaces on the packet delivery of NoCs are determined. Besides, some extensions to evaluate a fault-tolerant method and some routing algorithms are described. The analyses are validated through appropriate simulations. The results thus obtained are exactly the same as or very close to the analytical ones.