Mechanical Performance Study of Beam-Column Connection with U-Shaped Steel Damper.

The article proposes the use of a semi-rigid energy-dissipation connection combined with a U-shaped metal damper to avoid brittle failure of rigid steel beam-column connections under seismic loading. The U-shaped metal damper connects the H-section column and the H-section beam to form a new energy-dissipation connection as an energy-dissipation member. Compared with the existing research, this connection has a stable energy-dissipation performance and great ductility. To clarify the mechanism of energy dissipation, mechanical models under two U-shaped damping deformation modes are established. The calculation formulas for the yield load and stiffness are derived for the corresponding deformation mode using the unit load method. Taking the T-shaped beam-column connection and the application of U-shaped steel damper in the beam-column connection as an example, the mechanical model of the connection is established and the calculation formulas for the yield load and stiffness are derived. At the same time, the connection is subjected to a quasi-static test under cyclic loading. The results show that the hysteretic curve of the test is complete and that the skeleton curve is accurate compared to the theory. The error range of the initial stiffness and yield load obtained by the test and the theoretical formula is kept within 20%, indicating that the theoretical formula is reasonable and feasible. In addition, the correctness of the finite element model is verified by establishing a finite element model and comparing it with the test. The mechanical responses of purely rigid connections and rigid semi-rigid composite connections are compared and analyzed using a multi-story and multi-span plane frame as an example. The results show that the model with semi-rigid connections, compared to the model with rigid connections, avoids the gradual loss of bearing capacity caused by the failure of the connection area of the second floor of the main structure and improves the seismic performance of the main structure.

Combined Effects of Family History of Cardiovascular Disease and Serum C-reactive Protein Level on the Risk of Stroke: A 9.2-year Prospective Study among Mongolians in China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>We aimed to evaluate the combined effect of a family history of cardiovascular disease (CVD) and high serum C-reactive protein (CRP) on the stroke incidence in an Inner Mongolian population in China.</p><p><b>METHODS</b>A prospective cohort study was conducted from June 2002 to July 2012, with 2,544 participants aged 20 years and over from Inner Mongolia, China. We categorized participants into four groups based on the family history of CVD and CRP levels.</p><p><b>RESULTS</b>We adjusted for age; sex; smoking; drinking; hypertension; body mass index; waist circumference; and blood glucose, triglycerides, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels. Compared with the group with no family history of CVD/low CRP levels, the group with family history of CVD/high CRP levels had a hazard ratio (HR) of 1.78 [95% confidence interval (CI), 1.03-3.07; P = 0.039] of stroke, and an HR of 2.14 (95% CI, 1.09-4.20; P = 0.027) of ischemic stroke. The HRs of hemorrhagic stroke for the other three groups were not statistically significant (all P > 0.05).</p><p><b>CONCLUSION</b>Participants with both a family history of CVD and high CRP levels had the highest stroke incidence, suggesting that high CRP levels may increase stroke risk, especially of ischemic stroke, among individuals with a family history of CVD.</p>

[Randomized controlled trials of needle knife therapy combined with rotation traction manipulation for the treatment of cervical spondylotic radiculopathy].

OBJECTIVE: To compare the therapeutic effects between needle knife therapy combined with rotation traction manipulation and rotation traction manipulation for the treatment of cervical spondylotic radiculopathy. METHODS: From November 2013 to June 2015, 80 patients with cervical spondylotic radiculopathy meeting the inclusion criteria were divided into two groups randomly:the control group in which 39 patients were treated with rotation traction manipulation, and the treatment group in which 41 patients were treated with needle knife combined with rotation traction manipulation. The patients in the control group were treated once dayly for 2 weeks, which was 1 course. The patients in the treatment group were treated with needle knife firstly once a week for 2 weeks, which was 1 course;then were treated with the same methods as the patients in the control group. The symptoms, signs score and the therapeutic effects of the two groups before and after treatment were observed. RESULTS: After treatment, symptoms and signs scores declined in both groups(P<0.05). The results of the treatment group were better than effects in the control group(P<0.05). In the treatment group, 19 patients got an excellent result, 16 good, 5 fair and 1 bad;while in the control group, 10 patients got an excellent result, 10 good, 16 fair and 3 bad;the results of the treatment group were better than the results of the control group(P<0.01). CONCLUSIONS: Needle knife combined with rotation traction manipulation is an effective method for the treatment of cervical spondylotic radiculopathy, which is better than using manipulation method simply. Needle knife therapy has follow advantages:improving local blood circulation, reducing local content of pain substance, increasing production of substances resisting pain, opening channels and collaterals, and make body reaching new static and dynamic balance on the new foundation.

[Effects of moxibustion on expression of hypothalamic POMC mRNA and PDYN mRNA in rats with rheumatoid arthritis].

OBJECTIVE: To explore the central mechanism of moxibustion on analgesic effect. METHODS: Male Wistar rats were screened by pain threshold value before making model, and 48 rats whose pain threshold was (250 +/- 25) g were selected. Twelve male Wistar rats were randomly selected as a normal group. For the rest rats the rheumatoid arthritis (RA) model was duplicated by raising in a windy, cold and wet environment combined with injection of Freund's complete adjuvant (FCA), and then they were randomly divided into a model group, a moxibustion group and a moxa volatile oil group, 12 rats in each group. The moxibustion and the moxa volatile oil igroup were treated with moxibustion and moxa volatile oil at "Shenshu"(BL 23) and "Zusanli"(ST 36), respectively, for 15 days. No interventions were added on the model group and the normal group. The pain threshold in Iinjured foot and the expression of hypothalamic POMC mRNA and PDYN mRNA in rats were observed. RESULTS: Compared with the normal group, the pain threshold and the expression of hypothalamic POMC mRNA and PDYN mRNA in the model group were increased (all P < 0.01). Compared with the model group, the pain threshold and the expression of hypothalamic POMC mRNA and PDYN mRNA in the moxibustion group were increased significantly (all P < 0.01), but no statistically significance in the moxa volatile oil group (P > 0.05). Compared with the moxa volatile oil group, the above-mentioned observative indices in moxibustion group were all increased significantly (all P < 0.01). CONCLUSION: Moxibustion has obvious analgesic effect and its mechanism may be related to the increasing expression of hypothalamic POMC and PDYN mRNA through the warming effect of moxibustion.