Electrochemical impedance spectrum has been used in this work to study the critical chloride concentration for the rebar corrosion in fly ash concrete. The analysis and criteria for the critical corrosion point of rebar have been interpreted, and the surface morphology of the corroded rebar has been studied using SEM. The influences of the wet-dry cycling period and the fly ash content on the impedance spectra and the critical chloride concentration have been discussed respectively. It shows that the critical corrosion point can be precisely manifested by impedance spectra; the resistance of the concrete layer increases with increasing period of wet-dry cycling and increasing content of fly ash, which can be observed as translation of the spectra to the right on the complex plane; the critical chloride concentration tends to increase with increasing period of wet-dry cycling; the critical chloride concentration for rebar corrosion can be increased by a small dosage of fly ash in the concrete.
Objective
To investigate the predictive effects of perspiration-nerve examination on diabetic automomic neuropathy (DAN) in patients with type 2 diabetes mellitus (T2DM).
Methods
A total of 164 T2DM outpatients and inpatients were recruited from August 2008 to December 2009 (male 88, female 76, aged 41 to 70 years, mean (56±11) years). They were divided into non-DAN symptom group (n=98) and DAN symptom positive group (n=66) according to neuropathy symptoms evaluation form, and also divided into cardiovascular reflex test (CRT) positive group (n=92) and CRT negative group (n=72). Another 40 healthy individuals were served as controls. The positive rate of these two assessment methods was calculated. All patients and healthy adult volunteers underwent perspiration-nerve test and Ou Minuo plaster color changing time test. Student's t test and Chi-square test were used for statistic analysis.
Results
DAN symptom positive rate in 164 T2DM patients was 40.2% (66/164), the positive rate of cardiovascular reflex test was 43.9% (72/164), and the perspiration-nerve test had the positive rate of 45.1%(74/164). There was no significant difference between positive rate in perspiration-nerve test, DAN symptom test and cardiovascular reflex test (χ2 values were 3.12 and 1.22, both P> 0.05). The positive rate of cardiovascular reflex test in patients with positive DAN symptoms was 63.6%(42/66), significantly higher than in patients with negative DAN symptoms (30.6% (30/98); χ2 =17.46, P<0.01). And the positive rate of perspiration-nerve test in patients with positive DAN symptoms was 90.9% (60/66), significantly higher than in patients with negative DAN symptoms (14.3% (14/98); χ2=93.51, P<0.01). In DAN symptom positive group, Ou Minuo plaster color changing time of the left and right foot was (18±6) and (18±6) min, significantly longer than that in the non-DAN symptom group (t values were 22.848 and 23.694, both P<0.01). In cardiovascular reflex test positive group, the positive rate of perspiration-nerve test was 94.4% (68/72), significantly higher than that in the cardiovascular reflex test negative group (6.5% (6/92); χ2=126.09, P<0.01). In the cardiovascular reflex test positive group, Ou Minuo plaster color changing time of the left and right foot was (21±6) and (22±6) min, significantly longer than that in the cardiovascular reflex test negative group (t values were 36.841 and 36.126, both P<0.01). Ou Minuo plaster color changing time was positively related to cardiovascular reflex test (r=0.67, P<0.01), and was negatively related with heart rate difference per minute with deep breathing (r=- 0.46), Valsalva index (r=-0.38) and 30/15 ratio (r=-0.32) (all P<0.01).
Conclusion
DAN in patients with T2DM could be detected early by using perspiration-nerve function evaluation.
Key words:
Diabetes mellitus, type 2; Cardiovascular reflex test; Perspiration
We randomly assigned 139 patients with obesity to time-restricted eating (eating only between 8:00 a.m. and 4:00 p.m.) with calorie restriction or daily calorie restriction alone. For 12 months, all the participants were instructed to follow a calorie-restricted diet that consisted of 1500 to 1800 kcal per day for men and 1200 to 1500 kcal per day for women. The primary outcome was the difference between the two groups in the change from baseline in body weight; secondary outcomes included changes in waist circumference, body-mass index (BMI), amount of body fat, and measures of metabolic risk factors.
Urban subway construction inevitably causes disturbances to the rock strata. It can even cause ground collapse accidents when construction encounters a bad geological body in the stratum. To verify the influence of cavities on surface settlement and the mechanism of formation instability, the instability mechanism of cavity‐bearing strata under tunnel excavation disturbance was herein studied by tests using self‐designed indoor models and numerical simulations. This study was based on the concrete project case of Qingdao Metro. Two groups of experiments (with and without cavities) were designed to simulate the four‐step excavation by staged unloading of an airbag. The results show that the settlement value in the cavity state was about twice as much as that in the nonvoid state at the same stage. Besides the first step of excavation, in the numerical simulation, the settlement value of the same stage is about 1.3 times that of the model test. Simulating the deformation process of the surrounding rock in model tests shows that, in the excavation of the tunnel, the collapse surface of the tunnel arch roof will be connected with the sliding surface of the formation cavity. The cavity will gradually change from a regular circle to an ellipse or may even close, resulting in a sudden increase in land subsidence or even ground collapse. This indicates that disturbance during tunnel excavation would cause greater instability in a stratum when bad geological bodies, such as cavities, exist in the stratum.
Abstract Taking the TBM water inrush accident in An-Xue section of Qingdao Metro Line 1 as the engineering background, the research is carried out from two aspects of TBM water inrush emergency measures and grouting reinforcement treatment technology, which can ensure the strength of stratum reinforcement and water shutoff, and at the same time prevent the slurry from damaging the cutter head. For different areas, the grouting construction technology is proposed. After the reinforcement, the water stopping effect is obvious, the water inrush point has no water flow out, the hole drilling effect is good, the core removal rate is 75%∼85%, and the strength meets TBM excavation requirements.
BACKGROUND:At present there are several kinds of medicine for treating acute gout arthritis (AGA). This study compared the efficacy and safety of prednisolone, etoricoxib, and indomethacin in the treatment of AGA. MATERIAL AND METHODS:This was an open-label, randomized, active-comparator study in patients with AGA. Patients were randomized to 4 days of prednisolone 35 mg qd, etoricoxib 120 mg qd, or indomethacin 50 mg tid. The primary efficacy endpoint was the reduction of self-assessed pain in the index joint from baseline. Secondary endpoints included changes in physician's assessment of tenderness, erythema, swelling, and joint activity; patient assessment of response to therapy; and safety. RESULTS:We analyzed 113 patients. Baseline demographics were comparable among treatment groups. Oral prednisolone, etoricoxib, and indomethacin were similarly effective in improving pain, tenderness, and joint activity over 4 days. For inflammation, oral prednisolone, etoricoxib, and indomethacin were similarly effective in reducing erythema, but prednisolone might be more effective in reducing swelling than indomethacin. The patient response to therapy was similar in the 3 groups. There were more total adverse events with indomethacin compared with the other 2 drugs. CONCLUSIONS:Efficacy was comparable among prednisolone, etoricoxib, and indomethacin for the treatment of AGA. Prednisolone might be more effective in reducing inflammation and it had a better safety profile.
Abstract This paper takes Qingdao subway station as an example, considers reducing the cycle of track laying on the whole line, and adds rails and wells under the existing envelope structure. The single-track row of wells and a double-line entrance to the crossing are proposed. The analytical calculations and numerical simulation methods were used to check the mechanical condition of the station envelope and the main structure of the station under the rails. The research results show that the track laying base can be laid out in the enclosed open excavation station, and a series of problems such as land occupation coordination have been solved, and the period benefit is significant. This scheme can ensure the structural safety before the entrance of the rail row well is closed, and the position of the rail side frame below the middle plate of the station satisfies the requirements of the laying limit. This method has a novel design idea, has high application and promotion value, and provides a good reference for the design and construction of open-cut subway stations.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)