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Anorexia nervosa (AN) is a mental disorder characterized by a preoccupation with thinness and may be associated with brain structural alteration. The aim of the study was to examine the brain structural alteration in AN patients, including subcortical structure volume and cortical thickness. Thirty-five un-medicated AN patients and 20 matched healthy controls underwent structural magnetic resonance imaging brain scans. High resolution structural images were acquired on a SIEMENS 3T scanner and preprocessed using FreeSurfer software. Subcortical structure volume and cortical thickness were compared between the two groups. We found larger percentage of caudate volume relative to total grey matter (GM) volume in the AN group. Reduced cortical thickness at the left precuneus was also observed in AN patients. Moreover, an interaction between group and hemisphere was found, suggesting that cortical thinning was more prominent in the left hemisphere in AN patients. These findings provide further evidence for structural brain abnormalities in patients with AN.

Based on Boltzmann’s viscoelastic theory, the confined buckling behavior of a viscoelastic ring subjected to constant temperature difference is investigated by assumed modes method, Galerkin method and numeric method. The critical load and the stability of the solution are investigated. The evolutionary trend of the system is also analyzed.

It is difficult in finite element model(FEM) updating, because the essence is a mechanical anti-question solving. In the paper, the suppositional material method is utilized to model the FEM of a mirror frame system, and the required updating parameters are defined. The functions between the natural frequency and the updating parameters are established based on the response surface method. Based on the response surface model and the modal experiment results, the sum of absolute value of relative errors between the results of experiments and simulations is defined as the optimization objective, four required updating are identified automatically. The first three natural frequencies of updated mirror frame system are better accordant with the experiment results, which proves the method correct and reliable.

All measurements have error that obscures the true value. The error creates uncertainty about the quality of the measured value, which is requiring testing and calibration laboratories to provide estimates of uncertainty with their measurements. Measurement uncertainties include input uncertainty, the propagation of input uncertainty, the output uncertainty and the systematic error uncertainty. Several methods for estimating the uncertainty of measurements have been introduced for different kinds of uncertainty quantification, and two data mining methodologies-Artificial Neural Network (ANN) and Support Vector Machine (SVM) are used to build the unknown propagation model. This paper will discuss the quantification of measurement uncertainty (MU) and the separation of various uncertainty sources to MU and will discuss the advantages and limitations of SVM and ANN for building the propagation model of MU.

Based on the dynamic theory of flexible multi-body systems, a nonlinear dynamic model is established of a long shaft rotor system with a stabilized elastic bearing located along the shaft at an arbitrary position by the generalized Hamilton’s principle. Lower-order polynomials are adopted to construct the Ritz basis for investigating the first two vibration frequencies and the critical rotational velocity, as well as the optimal stabilized position of the elastic bearing. The critical rotational velocity and optimal stabilized position of the elastic bearing are also verified by the finite element method. The results obtained by the two methods agree well. Then, the post-buckling and the nonlinear vibration responses of the system fluctuating at the rotational velocity are investigated. The present study indicates that critical rotational velocity exists for the long shaft rotor system with stabilized elastic bearing. Once the rotational velocity exceeds the critical value, the system’s trivial equilibrium state losses its stability by pitchfork bifurcation. The optimal stabilized position of the elastic bearing for the long shaft rotor system is located at 73% length of the shaft from the pinned end. When in the supercritical state, the system changes to different vibration modes with local period-1 solutions and global period-2 solutions around the post-buckling position due to fluctuation of the rotational velocity. Furthermore, the global period-2 vibration may evolve to the almost periodic motion as the fluctuation frequency varies. This study provides a theoretical basis for understanding the geometrical nonlinear effect and vibration modes of the long shaft rotor system working in the supercritical state.

The incidence of dementia based on DSM-III criteria and the impact of age and education on the development of dementia using the data of a longitudinal community population survey is discussed. Study subjects were randomly sampled from the community and were assessed by a two-stage procedure twice during a 5-year period. The screening instrument was the Mini-Mental State Examination and the second stage measures include a medical history and physical examination, a neurological examination and an intensive neuropsychiatric interview and testings (i.e. Blessed Dementia Scale, Activity of Daily Living, Fuld Object Memory Test and Block Design Test. All identified cases from the second stage interview were further verified by computed tomographic scan and laboratory tests. A total of 1970 subjects of non-dementia aged 65 or older in 1987 were re-surveyed after 5 years, of whom 114 new cases of dementia were identified. The incidence of dementia in total was 1.15% annually, 0.98% for males and 1.27% for females. The incidence for Alzheimer's disease, vascular dementia and dementia by other causes was 0.74, 0.33 and 0.08%, respectively. The highest rate (2.02%) was found in illiterate individuals. The incidence of dementia in the Shanghai cohort is similar to that from other countries. Age and education are closely related to the occurrence of dementia. While age increases by each 5 years for those aged 65 and over the likelihood of developing dementia increases nearly one-fold (74%). Education shows great protective effect on the development of dementia. The non-educated has a higher risk of suffering from dementia than does the educated.

MicroRNA are a group of non-coding RNA which, through regulating expression of proteins at post-transcription level, plays an important role in modulating growth and development of nervous system, cell differentiation and functions. Altered expression of microRNA in the brain may influence development and advance of Alzheimer's disease from multiple perspectives. Research on microRNA will facilitate in depth understanding of the pathogenesis of Alzheimer's disease.

The analysis of parametric probabilistic sensitivity analysis is important for reliability-based design, which shows changes of system reliability caused by the change of basic variances. In this paper, a fast approximate method of reliability analysis based on the commercial FE simulation-artificial neural network-Monte Carlo simulation is proposed, which can save the calculation cost with efficient precision. With this quick-response model, a new scaling parameter is presented here considering the global dispersity of stochastic parameters, and the parametric probabilistic sensitivity is analyzed too. The sensitivity indices can be computed by the simple and approximate formula in engineering. A numerical example is presented to validate the accuracy and efficiency in reliability and parametric probabilistic sensitivity by comparing with the analysis of ANSYS.

To investigate the characteristics of hydrogen proton magnetic resonance spectroscopy (H-MRS) in posterior portion cingulate gyrus and the correlations thereof with the results of mini-mental state examination (MMSE), Alzheimer disease assessment scale-cognitive (ADAS-cog) in patients with mild-moderate Alzheimer's disease (AD).H-MRS in posterior portion cingulate gyrus was conducted in gender, age, and educational background-matched 24 patients with AD, 8 patients with vascular dementia (VD), and 11 normal controls (NC group) to measure the values of NAA (N-acetyl aspartate)myo-inositol (mI), and creatine and phosphocreatine (Cr). All the 4 subjects underwent MMSE and assessment with ADAS-cog as well. The correlations among these results were assessed.The NAA/Cr ratios in posterior portion cingulate gyrus of the AD and VD groups were (1.24 +/- 0.12) and (1.25 +/- 0.15) respectively, both significantly lower than that of the NC group [(1.46 +/- 0.19), P = 0.003, P = 0.017] without significant difference between the AD and VD groups (P = 0.800). The mI/Cr value of the AD group was (0.74 +/- 0.15), not significantly different from that of the VD group [(0.65 +/- 0.15), P = 0.153], and significantly higher than that of the NC group [(0.62 +/- 0.09), P = 0.007], however, the mI/Cr value of the VD group was not significantly different from that of the NC group (P = 0.662). If the NAA/Cr ratio1.31 was used as criteria of AD, the positive predictive value of AD was 73% and negative predictive value was 71%. The NAA/Cr ratio was positively correlated with the MMSE score (r = 0.731, P = 0.000), and negatively correlated with the ADAS-cog score (r = -0.541, P = 0.011).The NAA/Cr ratio decreases in the posterior portion cingulate gyrus of AD patients, and has statistical significant correlations with the score of MMSE and ADAS-cog. The H-MRS characteristics of posterior portion cingulate gyrus cannot effectively differentiate the early AD from early VD.

To study the brain volume changes of patients with Alzheimer's disease (AD).23 patients with (AD and 23 sex, age, and educational background-matched normal controls (NC group) underwent three-dimensional MRI to measure the hippocampus, amygdala, entorhinal cortex (EC), perirhinal cortex (PC), cornu temporale, and uncus distance in the baseline survey. Two years later 10 AD patients and 11 normal controls underwent 3-D MRI once again in the follow-up survey.The baseline survey showed that the levels of uncus distance and total temporal horn volume of the ADS patients were 11 +/- 4 and 1.21 +/- 1.00 respectively, both significantly higher than those of the NC group (7 +/- 3 and 0.59 +/- 0.54 respectively, P0.01, P0.05), and the levels of total entorhinal cortex volume, total perirhinal cortex volume, and total hippocampus volume were 2.52 +/- 0.86, 2.19 +/- 0.62, and 3.23 +/- 0.75 respectively, all significantly lower than those of the BC group (3.67 +/- 0.54, 3.39 +/- 0.51, and 3.98 0.38, all P0.01). The levels of uncus distance and total temporal horn volume of the AD patients during the follow-up survey were 11 +/- 4 and 1.21 +/- 1.00 respectively, both significantly higher than those of the NC group (7 +/- 3 and 0.59 +/- 0.54 respectively, both P0.05); and the total entorhinal cortex volume, total perirhinal cortex volume, and total hippocampus volume of the AD patients during the followup survey were. 1.79 +/- 0.56, 1.77 +/- 0.59, and 2.80 +/- 0.80 respectively, all significantly lower than those of the NC group (2.76 +/- 0.50, 2.76 +/- 0.41, and 3.59 +/- 0.38 respectively, all P0.01).The AD patients have more remarkable atrophy of entorhinal cortex, perirhinal cortex, and have obvious extension of cornu temporale and uncus distance in comparison with the normal controls. The shrinkage rate of hippocampus can be used as a marker for the diagnosis and progress of AD.

To study the change of cerebral metabolism rate of glucose (CMRglc) of cerebral white matter in Alzheimer's Disease.Positron emission tomography (PET) was performed on 13 AD patients, 6 with behavioral and psychological symptoms of dementia (BPSD) and 7 without BPSD, and 10 healthy controls. The regional cerebral metabolism of glucose (rCMRglc) of some brain regions and nuclei were detected.(1) The rCMRglc of the cerebral white matter decreased extensively in the AD patients, especially in the right frontal lobe, superior gyrus of the left frontal lobe (P = 0.001). (2) The rCMRglc of subcortical white matter of the left medial prefrontal lobe and the left cuneus of occipital lobe increased in the AD patients. (3) The levels of rCMRglc of the subcortical white matter of both side middle occipital lobe, left cuneus of occipital lobe, right inferior parietal lobule, left fusiform gyrus of temporal lobe and the left medial prefrontal lobe were all significantly higher in the AD patients with BPSD than in those without BPSD (P = 0.001). While the levels of rCMRglc of the subcortical white matter of both side paracentral lobule, right superior and middle frontal lobe, and left superior temporal lobe were all significantly lower in the AD patients with BPSD than in those without BPSD (all P = 0.001).There is diffuse abnormal rCMRglc in the cerebral white matter in the AD patients: the rCMRglc decreases in the frontal-temporal-occipital association area, and the rCMRglc of the medial prefrontal lobe and cuneus of occipital lobe increases. BPSD is correlated with the abnormal metabolism of related cerebral regions.

To establish a Chinese T-score norm of neuropsychological test battery for the elderly (NTBE).903 normal elderly people over 60 years old from Shanghai, Beijing, Hebei, Jiangsu, Hubei, Hunan, Zhejiang, Shandong and Liaoning were evaluated by using NTBE which includes tests of auditory verbal learning, sorting, cancellation, language, motor, visual function, construction, trail making 1 and 2, etc.Age and education greatly affected the score of NTBE, but gender did not. Based on these facts, the 903 normal subjects were divided into 12 subgroups, according to the age and the years of education they had received. The raw scores of NTBE were transformed to standard score and normalized standard score, and then these scores were transformed to a total T score (Mean = 100, SD = 10). Using another normal elderly sample (n = 474) to analysis, the correlation between the raw scores and the total T score was significant. Using NTBE to diagnose 110 mild cognitive impairment (MCI) and 63 Alzheimer's disease (AD) patients, the sensitivity and specificity were 66% and 91% for MCI, and 79% and 96% for AD.The T norm of the NTBE is suitable for Chinese elderly, and can be a useful instrument for diagnosing mild cognitive impairment and Alzheimer's disease.

To measure the changes of regional cerebral metabolism rate of glucose (rCMRglc) in patients with Alzheimer's disease (AD) and explore their value to diagnosis of AD.10 patients with AD who met the diagnostic criteria of DSM-IV and 10 normal controls (NC) were assessed with (18)F-2-fluoro-deoxy-D-glucose positron emission tomography (PET).The two groups were matched in age, gender and education. The mean total scores of the mini-mental status examination (MMSE) were 16.5 +/- 6.1 for AD and 28.7 +/- 1.6 for NC. The mean total memory quotient of Wechsler Memory Scales (MQ) were 32.3 +/- 19.6 for AD and 93.1 +/- 9.0 for NC. Comparing to NC, the AD groups showed statistically significant decline of rCMRglc in frontal lobe, temporal lobe and the hippocampal formation with decreased rates ranged from 3.3% to 28.4% (P0.05, P0.01). The hypo-metabolism was more salient in the regions of upper and middle frontal gyri, middle temporal gyrus, orbital gyrus and anterior cingulate gyrus, in which areas the metabolism decreased over 20% compared to NC. The hypo-metabolism was correlated to the severity of dementia. Discriminant analysis demonstrated that the variables of right inferior temporal gyrus, left upper temporal gyrus, left hippocampus and right insular lobe were entered into the discriminant functions and the total discriminant accuracy reached 100%.(18)F-FDG PET is a very sensitive tool in measurement of the changes of rCMRglc in patients with AD. The findings show a frontal-temporal type of metabolism in AD patients and suggest that hypo-metabolism in hippocampal formation and temporal lobe is helpful in early detection of AD.

Objective There are few studies of successful aging in China. This study was designed to investigate the distribution, and related factors, of successful aging in an elderly Chinese population. Methods A cross-sectional, community-dwelling elderly population was surveyed in Shanghai, China. We defined successful aging based on a multi-dimensional model. Correlates of successful aging were explored through the Shanghai Successful Aging Project Questionnaire, which includes sociodemographic questions, and a battery of standardized instruments, including the Chinese version of the Mini-mental State Examination, activities of daily living, and the Life Satisfaction Index A (LSIA). Results The rate of successful aging was 46.2% [95% confidence interval (CI) 43.6-48.7] among people aged 65 or above, and the rate for males was higher than that for females. The rate was much lower for those aged 85 years or over (9.4%). Logistic regression analysis suggested that female gender and older age were unfavorable factors for successful aging. A higher score on the LSIA, more leisure activities and being currently married related to successful aging. Conclusion The rate of successful aging in Shanghai, China is similar to that found in studies from western countries. There are some potentially modifiable factors that may relate to successful aging.

It is difficult to get large numbers of data in the process of measurement and performance analysis for material and structure, while many situations in complex systems require quantitative estimates of the lack of information in one probability distribution. Considering unknown probability distribution and very small sample data, based on the original fuzzy norm method, two improved methods are presented. Using membership function and theory of minimization of maximum module norm, the probability distribution function and the interval evaluation under the given confidence level can be obtained for the data series with poor information by solving the optimization problem. Finally, all the given methods and the traditional statistical method are compared and analyzed.