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Definition based on the incremental theory of plasticity of J integral, combining the method of experiment and computer simulation, the method of crack propagation rate based on elastic-plastic mechanics is studied, the research shows that the crack growth rate curve obtained by the incremental plastic J integral is well described the material fracture mechanics performance characteristics, ΔJ integral as the crack growth driving force is verified the rationality of the parameters, in order to further research to explore mechanism of crack extension provides research foundation, a new model is proposed based on the 7N01 aluminum alloy test data, it takes into account the effect of stress ratio on crack propagation, and it is suitable for estimating fatigue life of materials in engineering practice.

In order to obtain the novel poly(ε-caprolactone) (PCL) cross-linked networks with good shape memory properties, the cross-linked networks of PCL with different molecular weights were prepared by thiol-ene click chemistry method, and its microstructure, thermal properties, mechanical properties and shape memory properties were characterized. The results show that the hydroxyl end of PCL was successfully converted to acrylate-terminated PCL, and almost all the samples show perfect cross-linked network, and the cross-linked polymer has a thermally induced shape memory effect; with the increase of the molecular weight of PCL diol, the melting temperature and crystallinity of the cross-linked network also show an upward trend; the molecular weight of PCL diol has a certain influence on its fixation ability, but regardless of the length of PCL diol, the shape recovery rate of all samples can reach more than 90%. The efficient thiol-ene click chemistry reaction ensures the uniform distribution of PCL chains between cross-linked nodes, the cross-linked network has good network structure, good mechanical and shape memory properties. The exploration of new PCL cross-linked network provides a feasible way for the end functionalization of polymers.

High-resolution synthetic aperture radar presents a significant challenge to imaging algorithms and computing power. Slide spotlight is an important mode that has both high resolution and wide azimuth swath. Generally, in the slide spotlight mode, the performance of conventional frequency domain imaging algorithms degrades because of orbit curvature, the time-variant azimuth chirp rate, and other factors. We adopt the Back-Projection (BP) algorithm in this study to counteract this limitation. We also propose a CPU/GPU heterogeneous BP algorithm to deal with the high computing complexity O(N3) of the BP algorithm. This heterogeneous BP algorithm makes full use of computing resources and accelerates imaging progress, and the design of a scheduling thread improves the flexibility of the algorithm.

Bistatic Synthetic Aperture Radar (BiSAR) in one-stationary mode has many advantages over the traditional monostatic SAR. Its echo, however, shows serious space variance in both range and azimuth directions due to its complex imaging geometry, making it hard to be processed by the frequency methods used in the monostatic SAR. To solve that problem, a method based on blocks and interpolation has been proposed by Wang Yu et al.. With this method, points can be well focused except for those located on the edge of each block. In this paper, a modified method is put forward, which adopts new block-dividing strategy and new mapping relationship in the interpolation. With the proposed method, points on the edge can also be well focused, making the quality of the final image greatly improved.

To solve the load imbalance and network reliability problems faced by multi-controller deployment in software-defined flying ad-hoc network, an intelligent deployment method based on label segmentation for controller is presented. This method can output the optimal number of controllers and the deployment location according to the capacity constraints and network structure of controllers without preset number of controllers. Based on the node's own characteristics and the related features, the node labels are given. The control domain is divided according to the labels, and the partitioning process is optimized through the cuckoo search algorithm. On this basis, the controller deployment location is determined considering the effects of controller average latency, load difference and control domain latency fluctuations. The simulation results show that the proposed algorithm can effectively reduce the number of controllers and deployment costs while guaranteeing network reliability. At the same time, it reduces the average controller latency and load difference, and ensures the relative balance of the average latency among the control domains, so as to achieve network balance. [ABSTRACT FROM AUTHOR]

Because of safety and minimally invasion, hysteroscopic surgery has gotten popularity and has become the routine for diagnostic and therapeutic interventions of intrauterine pathology. Advantages consist of short operating time, rapid postoperative recovery and low morbidity. However, during hysteroscopic surgery there are concerns about potential complications such as venous air and gas embolism. These are rare but hazardous complications, which can occur in all surgical procedures. In hysteroscopic surgery, large uterine veins may be exposed and are, therefore, entries for gas or air. A number of fatal cases have been described as case reports. Although awareness for air and gas embolism is raised this way, proper guidelines how to reduce the risk of venous gas or air embolism are lacking. The pathophysiologic difference between gas and air embolism is described herein because composition of the gases differs with their different physiologic effects. Signs and symptoms of patients are described, as early detection and intervention are crucial for survival. Furthermore, we provide guidelines for operating department personnel, surgeons, and anesthesiologists to reduce the risk of venous gas or air embolism during hysteroscopic procedures. Potential complications of these procedures may be prevented by this way. [ABSTRACT FROM AUTHOR]

The Guidelines for prevention and treatment of colorectal adenoma with integrated Chinese and western medicine are put forward by Nanjing University of Chinese Medicine and approved by China Association of Chinese Medicine. According to the formulation processes and methods of relevant clinical practice guidelines, the experts in clinical medicine and methodology were organized to discuss the key problems to be addressed in the clinical prevention and treatment of colorectal adenoma(CRA) and provided answers following the evidence-based medicine method, so as to provide guidance for clinical decision-making. CRA is the major precancerous disease of colorectal cancer. Although the prevention and treatment with integrated Chinese and western medicine have been applied to the clinical practice of CRA, there is still a lack of high-quality guidelines. Four basic questions, 15 clinical questions, and 10 outcome indicators were determined by literature research and Delphi questionnaire. The relevant randomized controlled trial(RCT) was retrieved from CNKI, Wanfang, VIP, SinoMed, PubMed, EMbase, Cochrane Library, Web of Science, and 2 clinical trial registries, and finally several RCTs meeting the inclusion criteria were included. The data extracted from the RCT was imported into RevMan 5.3 for evidence synthesis, and the evidence was evaluated based on the Grading of Recommendations, Assessment, Development, and Evaluations(GRADE). The final recommendations were formed by the nominal group method based on the evidence summary table. The guidelines involve the diagnosis, screening, treatment with integrated Chinese and western medicine, prevention, and follow-up of colorectal adenoma, providing options for the clinical prevention and treatment of CRA.

Objective: To observe the changes of the skeletal muscle fibrosis and changes of transforming growth factor-β1(TGF-β1)/ extracellular signal-regulated kinase (ERK) / connective tissue growth factor (CTGF)pathway in rats after long-term eccentric exercise and acupuncture intervention, so as to explore the mechanism of acupuncture in regulating exercise-induced skeletal muscle fibrosis., Methods: A total of 30 male SD rats were randomly divided into normal control, exercise and acupuncture group, with 10 rats in each group. The rat model of skeletal muscle fibrosis was established by eccentric exercise for 3 weeks. After exercise trained every time, the rats of the acupuncture group received acupuncture stimulation by holding the acupuncture needle to obliquely and longitudinally penetrate the ventral part of triceps of the lower leg along its lateral side, followed by retaining the needle for 2 min. Changes of the collagen fibers in each group was observed by scanning electron microscope. The expressions of Collagen Ⅰ, TGF-β1, phosphated (p)-ERK/ERK and CTGF proteins were detected by Western blot., Results: After 3 weeks of eccentric exercise and acupuncture, the fibrosis and deposition of collagen fibers in the exercise group were significantly higher than that in the normal control group,the degree of fibrosis in the acupuncture group was significantly lower than that in the exercise group. Compared with the normal control group, the expression levels of Collagen Ⅰ, TGF-β1, CTGF and p-ERK/ERK in the exercise group was significantly higher ( P <0.01， P <0.05). After EA interventions, the increased levels of the above indicators were significantly reversed ( P <0.05， P <0.01) apart from p-ERK/ERK which had a downward trend, but the difference was not statistically significant., Conclusion: The accumulation of chronic sports injury can lead to the deposition of collagen fibers in skeletal muscle, which leads to the fibrosis of skeletal muscle. Acupuncture can inhibit skeletal muscle fibrosis via down-regulating TGF-β1/ERK/CTGF signaling pathway.

Objective: To try to re-map an acupoint atlas in vector mode in the experimental rat by using a new-generation drawing tool., Methods: A total of 5 SD rats were used in the present study. In reference to the current acupoint locations and anatomical structure of rats as well as those of the human body, an acupoint atlas having a stereoscopic mode was re-mapped by using Adobe photoshop/illustrator CS6 imaging processing and drawing system., Results: According to the skeletal structure and body surface landmarks, an acupoint atlas consisting of Shuigou (GV26), Baihui (GV20), Tianmen (i.e. Cuanzhu, BL2), Erjian (MA-H6), Dazhui (GV14), Feishu (BL13), Xinshu (BL15), Geshu (BL17), Jizhong (GV6), Pishu (BL20), Shenshu (BL23), Houhui (SI3), Huantiao (GB30), Houhai, Yanglingquan (GB34), Housanli (ST36), Zhaohai (KI6), Sanyinjiao (SP6), Genduan point, Shenmai (BL62), Taichong (LR3), Zhijian (foot), Yongquan (KI1), Guanyuan (CV4), Xiqian, Weijian, Shenque (CV8), Zhongwan (CV12), Qiansanli (LI10), Waiguan (SJ5), Neiguan (PC6), Quchi (CV6), Zhoujie (EX-UE1), Hegu (LI4), Zhijian (hand), Houxi (SI3), Shenmen (HT7), Taiyuan (LU9), Shaohai (HT3), Chize (LU5), Danzhong (CV17), and Chengjiang (CV24) which have been positioned in plane graph mode by Professor HUA Xing-bang and colleagues in 1991. The newly re-mapped acupoint atlas displayed more clearly in the anatomic locations relevant to the traditional one., Conclusion: A new acupoint atlas with 3 dimension image mode is accomplished in the rat, being more convenient and applicable for researchers to edit the relevant graph materials in paper writing, and playing a possibly useful guidance for the standardization of acupoint selection in experimental acupuncture researches.

Ethanol concentration quantitative analysis of ethanol-water solution can be realized by measuring the ratio of Raman characteristic peak heights. The content of ethanol can be determined by linear relation between relative intensity ratio and ethanol concentration. However, this analytical method only applies to the ethanol solution at low concentration. Concerning this issue, relative intensity of characteristic peak of ethanol (asymmetric stretching vibration of CH2 2 924.0 cm-1) and peak background of water (3 350 cm-1) at different ethanol concentration is experimentally measured by using a self-developed laser Raman ethanol content detection system. According to the relationship between relative ratio of characteristic peak heights and ethanol concentration, the nonlinear regression analysis methods are proposed to apply in the measurement of ethanol concentration in a wide range. Adjacent region average method is utilized to remove mutational random noise in Raman spectra of ethanol solution. Combined with multi-point interpolation processing, the baseline of Raman spectra can be calibrated. The influences of mutational random noise and the strong fluorescence background can be effectively eliminated with baseline correction and normalization methods. Polynomial and exponential mathematical models are adopted for nonlinear regression analyses by the relation between ratio of characteristic peak heights and concentration of ethanol solution. The analysis results show that the correlation coefficient of linear fitting and nonlinear fitting is about 0.991 and higher than 0.997 respectively. The linear analytical method can be effectively applied when ethanol concentration range is 15%～60%. The nonlinear analytical method has higher measurement accuracy in a wider ethanol concentration range of 3%～97%. Nonlinear mathematical model will provide theoretical basis for analysis of ethanol concentration, which can be applied in laser Raman ethanol content detection system to calculate the relatively accurate ethanol concentration of ethanol-water solution. Rapid, real-time and accurate quantitative analysis of wide concentration range ethanol solution, which has mutational random noise and strong fluorescence background interference, can be achieved by these analytical methods.

Neuromyelitis optica (NMO) is a kind of demyelinating disorder that preferentially affects the optic nerves and spinal cord and results in permanent vision loss. There is no effective treatment so far. In recent years, monoclonal antibodies (mAbs) have been applied in a number of clinical drug trials and basic researches in NMO therapy due to its specificity and uniformity. Phase I clinical study found that, symptoms significantly improved in some patients after mAbs treatment. This review will expound the therapy classification, mechanism of action and clinical results involving mAbs, and provide reference for the clinical treatments of NMO.

Objective: To evaluate the clinical characteristics and reoperation of symptomatic adjacent segment degeneration postoperation of lumbar fusion., Methods: In the study, 28 cases of symptomatic adjacent segment degeneration postoperation of lumbar fusion from May 2007 to April 2012 were retrospectively reviewed,with an average age of (64.3±8.7) years. The mean period between reoperation and primary fusion surgery was (47.5±30.8) months. Symptomatic adjacent segment degeneration located in cephalic segments in 12 cases, in caudal segments in 14 cases and in both segments in 2 cases. Of all the 28 patients, 12 suffered from lumbar stenosis, other 13 from lumbar disc herniation and still other 3 from both lumbar stenosis and disc herniation, of whom 11 were together with segment instability. Localization diagnoses of 19 cases were clear and other 9 received diagnostic nerve root block. The cases were divided into two groups by the type of reoperation,of which 8 cases were in adjacent degenerative segment nonfusion group and the other 20 cases in adjacent degenerative segment fusion group. The clinical results were assessed by lumbar pain visual analog score (VAS) and lower limber pain VAS,lumbar Japanese Orthopedic Association (JOA) score and Prolo functional score before operation and in the final follow-up., Results: In adjacent degenerative segment nonfusion group, the average operation time was (86.3±17.1) min and average blood volume was (125.0 ±37.8) mL of reoperation and 1 case with dural injury; and in adjacent degenerative segment fusion group, the average operation time was (201.6 ±71.0) min and average blood volume was (313.6±218.9) mL of revision surgery and 4 cases with dural injury. The average follow-up period was 25.5 months. In the final follow-up,lumbar pain VAS,lower limber pain VAS,lumbar JOA score and Prolo functional score of adjacent degenerative segment nonfusion group were 2.4±1.2, 2.8±1.4,23.5±4.2 and 8.2±1.5,which were better than preoperation 5.5±2.9, 6.8±2.5, 13.7±5.2 and 4.3±2.1, P<0.001; lumbar pain VAS, lower limber pain VAS,lumbar JOA score and Prolo functional score of adjacent degenerative segment nonfusion group were 3.3±1.9, 3.1±1.2, 22.2±4.4 and 7.7±1.6, which were better than preoperation 5.4±2.7, 7.0±2.4, 13.0±5.6 and 3.9±1.9, P<0.001.In the final follow up, lumbar pain VAS of adjacent degenerative segment nonfusion group was better than that adjacent degenerative segment fusion group(P=0.028)., Conclusion: Symptomatic adjacent segment degeneration postoperation of lumbar fusion is difficult for diagnosis and treatment. Appropriate reoperation could get the good results.

Objective: To investigate the occupational stress status and influential factors of the peasant-workers in factory., Methods: 410 peasant-workers in factory were tested by revised work requirement-control table and occupational stress measurement tools, and data were statistically analyzed by analysis of covariance., Results: The scores of work requirement, mental health in male peasant-workers were higher than those in female workers. The scores of everyday sense of stress in female workers were higher than those in male peasant-workers (P < 0.05). Workers with higher education level scored more in decision making and less in mental health than ones with lower education levels (P < 0.05). The workers divorced scored more in occupational stress factors, everyday nervous sense of stress and work future prospects than other marriage status workers (P < 0.05). Living with the family scored more in self-respect sense, mental health than other living styles (P < 0.05). The workers exposed to higher levels of noises have more scores in occupational stress factors, everyday sense of stress, and have less scores in decision making and work requirement than those exposed to lever levels of noises (P < 0.05 or P < 0.01). The workers exposed to higher level of powder or chemical toxin had more scores in occupational stress factors, work requirements and less scores in mental heath than those exposed to lever of powder or chemical toxin (P < 0.05 or P < 0.01)., Conclusions: Gender, educational level, marriage status, living styles and work environment have some influence on occupational stressors and strains. Self-respect sense and occupational stress factors can impact mental health and depression symptoms.