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For acquisition of accurate aerodynamic parameters of the pipeline suspension bridge, the numerical wind tunnel model for the typical girder section of the oil and gas pipeline suspension bridge was built, and SST k-ε model was used as the numerical wind tunnel turbulence model. The bypass flow pressure field distribution acquired from the numerical wind tunnel shows that the negative pressure area on the upper and lower surfaces of the pipeline is obvious, the largest positive pressure area appears on the windward side of the pipeline, and the pressure difference between the windward side and the leeward side of the truss girder in the inflow direction is particularly obvious. The bypass flow velocity field distribution shows that the pipeline and truss girder exert significant blocking effect on the wind speed, and the flow separation and vortex shedding phenomena occur apparently on the pipeline, windward railings and truss girder. According to the root mean square pressure of the flow field, vortex vibration is most likely to occur in the inflow side truss. Through the analysis of the three component coefficients of different pipeline diameters and different girder widths at the wind attack angles of －3°, 0° and 3°, it is concluded that the girder width has little influence on resistance coefficient and lift coefficient, and the torsion coefficient decreases with the increase of the girder width at －3° wind attack angle. The pipeline diameter definitively influences the three component coefficients, that is, with the increase of pipeline diameter, the resistance coefficient increases gradually, while the lift coefficient and torsion coefficient decrease gradually. The research results are expected to provide wind-resistant data support for the design of suspension bridge deck structure and the piping layout.

PURPOSE: To investigate the prevalence and distribution of temporomandibular disorders (TMD) and the related factors to TMD in Uigur and Han young people (17-28 years) from Xinjiang Medical University. METHODS: A sample of 812 persons was randomly selected from Xinjiang Medical University. Subjective disorders were assessed using questionnaire, and objective symptoms were determined by clinical examination. The Anamnestic and Clinical Dysfunction Indices (Ai and Di) according to Helkimo were employed. SPSS13.0 software package was used for data analysis. RESULTS: The percentage distribution of the sample was as follows :AiO=73.40 %, Ai I+ II = 26.60%, Dio=60.50%, Di I - III = 39.50 %. CONCLUSIONS: The prevalence of temporomandibular joint disorders was 39.50%. In anamnestic symptoms and clinical symptoms, there was no significant different between the males and females. ③The incidence of TMD in malocclusion group was higher than that in group without malocclusion. TMD is associated with some factors as bruxism, lateral biting. [ABSTRACT FROM AUTHOR]

Objective To delineate the cerebral metabolic patterns presented in 18F-FDG PET images in various types of dementia with SPM analysis. Methods Patients who underwent 18F-FDG PET scanning with a retrospectively confirmed diagnosis according to strictly defined clinical research criteria were studied. Clinical follow-up enabled appropriate patient inclusion. A total of 62 patients were included, of which 20 patients were diagnosed as Alzheimer's disease (AD), 20 frontotemporal dementia (FTD), 10 dementia with Lewy body (DLB), 7 progressive supranuclear palsy (PSP), 3 primary progressive aphasia (PPA), 1 corticobasal ganglionic degeneration (CBD), 1 multiple system atrophy (MSA). 18F-FDG PET images of each group were analyzed and compared to 20 healthy controls using SPM5. Results Disease-specific patterns of relatively decreased metabolic activity were found in AD (bilateral parietotemporal regions and frontal regions sparing sensorimotor cortex), FTD (asymmetric frontotemporal regions), DLB (occipital lobe, visual cortex and bilateral superior temporal gyrus), PSP (bilateral dorsolateral prefrontal cortex, anterolateral temporal regions, caudate nucleus and mesencephalon), PPA (Broca's area in left frontal lobe, left temporal cortex excepting posterior superior temporal gyrus, CBD (asymmetricly involved cortical regions, prodominately on right side, around bilateral central sulcus and right basal ganglia), MSA (bilateral cerebellum dorsolateral cortex and left putamen), and right medial temporal cortex). Conclusions Specific dementia related cerebral metabolic patterns in 18F-FDG PET might assist in early differential diagnosis of neurodegenerative diseases. doi: 10.3969/j.issn.1672-6731.2014.04.008

Objective To delineate the pattern of reduction of cerebral glucose metabolism in patients with Alzheimer's disease (AD) and frontotemporal dementia (FTD) and investigate the value of 18F-FDG PET in the differential diagnosis. Methods Twenty patients with FTD (behavioral variant) and 20 AD patients underwent 18F-FDG PET scanning. All the images were compared with that from 20 healthy age-matched control subjects on a voxel-based analysis (VBA) using SPM5. Visual analyses of 18F-FDG PET were performed by 2 independent nuclear medicine specialists who were blinded to the clinical background. Results 1) The PET scans of all the patients in 2 groups presented impairment of cortical metabolism. 2) Subjects with AD showed hypometabolism in the bilateral temporoparietal association cortex and posterior cingulate cortex, and hypometabolim in part of bilateral frontal lobes was observed in patients with progression. The metabolic activity was relatively kept in the primary motor-sensor cortex, occipital lobes and subcortical structures (basal ganglia and thalamus). The asymmetric hemispheric hypometabolic involvement was rare and observed in only 2 of 20 cases. 3) Subjects with FTD showed a significant hypometabolism of the frontal lobes and anterior temporal lobes, accompanied by mild to moderate reductions in glucose metabolism in parietal cortices and subcortical structures. The asymmetric hemispheric hypometabolic involvement was commonly observed in 16 of 20 cases with right-dominant type in 4 of 16 cases and left-dominant type in 12 cases. Conclusions 18F-FDG PET is a reliable diagnostic test in distinguishing FTD from AD due to the sharp contrast pattern of cerebral glucose hypometabolism. doi: 10.3969/j.issn.1672-6731.2014.03.012

Alzheimer's disease is the most common cause of dementia in the current elderly population. PET can detect pathophysiological changes in Alzheimer's disease with different radiotracers. This paper will focus on evaluating the value of 18F-FDG, amyloid and tau protein PET imaging in Alzheimer's disease. PET has been demonstrated to play an important role in the research of etiology, early diagnosis, differential dignosis, prognosis and medical treatment of Alzheimer's disease. doi: 10.3969/j.issn.1672-6731.2014.03.007

Objective: To optimize and determine the artificial cultivated conditions of Phellinus igniarius by Response Surface Method., Methods: With the index for the content of hypholomine B which was the main component of alcohol extract of Phellinus igniarius, the effect factors such as cultivated temperature, humidity, substrate types and illumination time were investigated respectively. By univariate analysis of variance, three most influential factors designed by BBD ( Box-Behnken Design) response surface optimization were selected to determine the optimal combination of them., Results: Cultivated temperature, humidity and substrate types were the most significant factors, the influence order was as follows: cultivated temperature > humidity > substrate types. The optimal artificial cultivated conditions of Phellinus igniarius were as follows: cultivated temperature 35 degress C, humidity 95%, and substrates for wheat. Under the conditions, the average content of hypholomine B was 1.046%., Conclusion: Response Surface Method can be used for optimization of artificial cultivated conditions of Phellinus igniarius,which provides an experimental method for the optimization of cultivated conditions of medicinal resources.