Seismic behavior of bifurcated concrete filled steel tube columns with a multi-cavity structure

In order to meet the architecture and construction needs of high rise buildings, the special-shaped columns are becoming more and more widely used. In this study, cyclic tests on seven special-shaped bifurcated Concrete Filled Steel Tube (CFST) columns are carried out. Test variables are the column cross section types and the loading directions. The strength, ductility, hysteretic behavior, energy dissipation ability, failure modes and seismic mechanisms are analyzed. Test results show that: the cross-section type of the column is the main factor influencing the seismic behavior of the specimens. Compared with the basic cross section type, the strength, ductility and energy dissipation capacity of the strengthened cross section type all significantly increased. The cross sections with the inserted angle steel or circular steel tube have the best comprehensive seismic behavior. Also, the loading direction has a considerable influence on the seismic behavior. Compares with the short axis loading specimen C1-Y, the strength of the long axis specimen C1-X and 45° axis C1-Z increase by 92.5 % and 44.0 %, respectively, indicating that the differences in loading direction should be taken into consideration in the seismic design. Based on the test results, the FEM analysis are also carried out. The FEM results show a satisfactory agreement with experimental results. The concrete constitutive relationship and modelling method proposed is suitable for the simulation of special-shaped bifurcated CFST columns with multiple cavities

Uncoupling neurotrophic function from nociception of nerve growth factor: what can be learned from a rare human disease?

Nerve growth factor (NGF) is a powerful trophic factor that provides essential support for the survival and differentiation of sympathetic and sensory neurons during development. However, NGF also activates nociceptors contributing significantly to inflammatory pain and neuropathic pain after tissue injury. As such anti-NGF based therapies represent a promising strategy for pain management. Because of dose-dependent serious side effects such as back pain, injection site hyperalgesia, clinical trials of using NGF to treat various disorders such as diabetic neuropathies, chemotherapy-induced and human immunodeficiency virus-associated peripheral neuropathies were all discontinued. Thus far, worldwide clinical applications of NGF in treating patients are very limited except in China. Hereditary sensory autonomic neuropathy type V (HSAN V) is an extremely rare disease. Genetic analyses have revealed that HSAN V is associated with autosomal recessive mutations in NGF. One of the mutations occurred at the 100th position of mature NGF resulting in a change of residue from arginine to tryptophan (R100W). Although those HSAN V patients associated with the NGFR100W mutation suffer from severe loss of deep pain, bone fractures and joint destruction, interestingly patients with the NGFR100W mutation do not show apparent cognitive deficits, suggesting important trophic support function is preserved. We believe that NGFR100W provides an ideal tool to uncouple the two important functions of NGF: trophic versus nociceptive. Studies from investigators including ourselves have indeed confirmed in animal testing that the NGFR100W no longer induced pain. More importantly, the trophic function seemed to be largely preserved in NGF harboring the R100W mutation. On the mechanistic level, we found that the NGFR100W mutation was capable of binding to and signaling through the tyrosine receptor kinase A receptor. But its ability to bind to and activate the 75 kDa neurotrophic factor was significantly diminished. The significance of these findings is at least two folds: 1) the NGFR100W mutation can be used as an alternative to the wildtype NGF to treat human conditions without eliciting pain; and 2) the 75 kDa neurotrophic factor may serve as a novel target for pain management. We will discuss all the details in this mini-review

Values of Different Obesity Indicators in Predicting the Risk of Hyperuricemia：a Comparative Study

BackgroundIn China, hyperuricemia (HUA) is increasingly prevalent, which is often accompanied by multi-system diseases, and has become the second leading metabolic disease after diabetes mellitus. How to effectively contain its prevalence has become an important public health issue that needs to be solved urgently.ObjectiveTo examine relationships of different obesity indices〔waist circumference (WC) , body mass index (BMI) , waist-to-height ratio (WHtR) , body shape index (ABSI) , body roundness index (BRI) , visceral adiposity index (VAI) and lipid aggregation index (LAP) 〕with HUA, and compare their predictive values for HUA, providing a reference basis for early HUA screening and prevention.MethodsCluster sampling was used to recruit physical examinees from the health management center of a grade A tertiary hospital from January to December 2020. Anthropometric indices included in the analysis included WC, BMI, WHtR, ABSI, BRI, VAI and LAP. Binary Logistic regression was used to assess the correlation of HUA with different obesity indices. Receiver operating characteristic (ROC) curve analysis was performed to estimate the predictive values of these indices for HUA with suggested optimal cut-off points presented.ResultsOf the 32 344 physical examinees in total, 13 546 (41.84%) were found with HUA. Men had higher detection rate of HUA than women〔54.11% (10 026/18 530) vs 25.43% (3 520/13 844) 〕 (P<0.001) . The values of all these obesity indices were higher in male HUA patients than in female HUA patients, with statistically significant differences (P<0.001) . Binary Logistic regression showed that after correcting for confounding variables, WC, BMI, WHtR, ABSI, BRI, VAI, and LAP were all statistically associated with HUA occurrence in both men and women (P<0.001) . In men, the area under the ROC curve (AUC) of WC, BMI, WHtR, ABSI, BRI, VAI and LAP in predicting HUA was 0.612, 0.626, 0.602, 0.512, 0.602, 0.617 and 0.642, respectively, with corresponding optimal cut-off points of 80.5 cm, 24.3 kg/m2, 0.48, 0.072, 3.8, 1.4 and 26.7. In women, the AUC for WC, BMI, WHtR, ABSI, BRI, VAI and LAP in predicting HUA was 0.637, 0.636, 0.637, 0.555, 0.638, 0.583, and 0.660, respectively, with corresponding optimal cut-off points of 72.5 cm, 22.7 kg/m2, 0.47, 0.074, 4.2, 1.3 and 15.3. In both male and female physical examinees, the AUC of LAP predicting HUA was higher than the other six obesity indicators (P<0.05) , and the AUC of ABSI predicting HUA was lower than the other six obesity indicators (P<0.05) .ConclusionThese seven obesity indices were all significantly associated with the occurrence of HUA in men and women. The predictive values of them for HUA were different, and LAP may be the best indicator for predicting the risk of HUA in either men or women