In order to improve the wearing comfort and bearing effectiveness of the exoskeleton, based on the prototype and working mechanism analysis of a relaxation wearable system for knee exoskeleton robot, the static optimization synthesis and its method are studied. Firstly, based on the construction of the virtual prototype model of the system, a comprehensive wearable comfort evaluation index considering the factors such as stress, deformation and the proportion of stress nodes was constructed. Secondly, based on the static simulation and evaluation index of system virtual prototype, multi-objective genetic optimization and local optimization synthesis of armor layer topology were carried out. Finally, the model reconstruction simulation data confirmed that the system had good wearing comfort. Our study provides a theoretical basis for the bearing performance and prototype construction of the subsequent wearable system.
ObjectiveTo evaluate the screening performance of commonly used renal function indicators for chronic kidney disease (CKD) in subjects of different ages, so as to explore the appropriate screening regimen for Chinese population.MethodsA total of 2 131 adult subjects in Sichuan Orthopaedic Hospital or Mianyang Central Hospital from May 2016 to October 2017 were selected. They were divided into three groups according to age: group A (18–39 years, n=278), group B (40–64 years, n=1 167), and group C (≥65 years, n=686). Serum levels of creatinine (SCr), urea, and cystatin C [CysC; to calculate estimated glomerular filtration rate (eGFR) based on this index], as well as urine levels of albumin, total protein and creatinine were measured, and urine albumin to creatinine ratio (ACR) and urine protein to creatinine ratio (PCR) were calculated respectively. CKD was diagnosed according to the Kidney Disease: Improving Global Outcomes (KDIGO) Guideline (2012 Edition). The receiver-operating characteristic (ROC) curve analysis was finally performed to investigate the diagnostic performance of each indicator for CKD.ResultsThe prevalences of CKD in group A, B, and C were 10.8% (30/278), 16.4% (191/1 167), and 45.8% (314/686), respectively, and the difference among these groups was statistically significant (χ2=233.525, P<0.001). In addition, the levels of the six renal function indicators between CKD and non-CKD subjects also had statistically significant differences in different age groups (P<0 05="" otherwise="" roc="" curve="" analysis="" revealed="" that="" the="" diagnostic="" values="" of="" these="" indicators="" were:="" acr="" or="" pcr=""> eGFR or CysC > serum urea or SCr (AllP<0 05="" except="" that="" egfr="" cysc="" serum="" urea="" and="" scr="" in="" group="" a="" assessed="" the="" similar="" diagnostic="" performance="" among="" the="" three="" indicators="" recommended="" by="" kdigo="" guideline="" the="" diagnostic="" performances="" of="" acr="" and="" pcr="" in="" different="" age="" groups="" were:="" group="" b="" 0="" 915="" 0="" 914=""> group A (0.885, 0.890) > group C (0.841, 0.846), while the diagnostic performance of eGFR was group C (0.807) > group B (0.728) > group A (0.696). The best boundary values of ACR and PCR were lower while the value of eGFR was higher than the corresponding KDIGO recommended medical decision levels.ConclusionsACR is the first choice for screening CKD when the renal function index creatinine is normal. Moreover, eGFR can further improve the diagnostic value, especially in subjects over 65 years old.