Search

In this paper, new preconditioned GAOR methods are proposed for solving a class of $ 2 \times 2 $ block structure linear systems arising from the weighted linear least squares problems. Comparison theorems are derived. Comparison results show that the convergence rates of the new preconditioned GAOR methods are better than those of the preconditioned GAOR methods in the previous literatures whenever these methods are convergent. A numerical example is given to confirm our theoretical results.

Background: Although homocysteine (Hcy) and white matter hyperintensities (WMH) have been proven to be correlated with increased risks of ischemic stroke, there have been few studies addressing the association between serum Hcy and WMH in a population with asymptomatic intracranial arterial stenosis (aICAS). Thus, the aim of the present study is to describe the association between Hcy and WMH in rural-dwelling Chinese people with aICAS. Methods: In this study, 150 participants diagnosed as aICAS by magnetic resonance angiography were recruited from the Kongcun Town Study, which was a population-based study aimed to investigate the prevalence of aICAS in general population aged 40 to 90 years old, free of ischemic stroke history, and living in the Kongcun town, Pingyin county, Shandong, China. Data on demographics, risk factors, and serum Hcy levels were collected via interview, clinical examination, and laboratory tests. The WMH volumes were calculated through the lesion segmentation tool system for the Statistical Parametric Mapping package based on magnetic resonance imaging. The association between Hcy and WMH volume was analyzed using both linear and logistic regression analysis. Results: After adjusting for all confounders, high Hcy (HHcy) (serum Hcy ≥15umol/L) was significantly associated with severe WMH (the highest quartile in WMH volume) (OR: 2.972, 95%CI: 1.017-7.979, P

Because of high heterogeneity, a further classification should be made for diagnosis and treatment in gastric cancer. Biomarkers selected in subtypes are important for precision medicine. Based on gene expression level, we constructed genome-wide co-expression networks for invasive, proliferative and metabolic subtype in gastric cancer respectively. The hierarchical clustering was used to get sub-networks, and hub gene sets of subtypes were got by analysis in sub-networks. Unique differential expression genes as candidate targeted genes in subtype were gained by a comparative analysis between subtypes. These genes may be helpful for improving diagnosis and therapy methods and developing new drug in gastric cancer.

For the first time, the current density convolution finite-difference time-domain (JEC-FDTD) method is extended to dispersive media using Crank–Nicolson difference scheme, and derive the one-dimensional JEC-CN-FDTD iterative equation of plasma. The incomplete Cholesky conjugate gradient (ICCG) is proposed to solve the large sparse matrix equation in the Crank–Nicolson finite-difference time-domain (CN-FDTD) method as the ICCG method improves speed of convergence, enhances stability and reduces memory consumption. The high accuracy and efficiency of the JEC-CN-FDTD method are confirmed by computing the characteristic parameters of electromagnetic wave through a collision plasma slab in one dimension, such as the reflection electric field, transmission electric field, magnitudes and phases of reflection coefficient and transmission coefficient. The results prove that the method performs stably, is of accuracy, and has certain advantages.

The Symplectic Finite-Difference Time-Domain (SFDTD) method was applied to simulate the one-dimensional unmagnetized Plasma Photonic Crystal (PPC) with a sandwich structure. Compared with the traditional Finite-difference Time-Domain (FDTD) method, the results from the SFDTD method are reliable and accurate. Also the SFDTD method has better numerical dispersion characteristics than the traditional FDTD method and the Multi-Resolution Time-Domain (MRTD) method too. Electromagnetic propagation process by differential Gaussian pulse is given in the PPC band gap with the SFDTD method used. The influence of the plasma frequency and the thickness ratio of plasma and medium to PPC on the band gap structure is analyzed. The plasma frequency most affects the PPC in low-frequency range. Also the propagation of an electromagnetic wave can be controlled by the thickness ratio of plasma and medium. The results above prove that the SFDTD method can give the right and better results on the research of PPC.

Osteoporosis is characterized by the progressive loss of bone mass and the micro‑architectural deterioration of bone tissue, leading to bone fragility and an increased risk of fracture. Gallium has demonstrated efficacy in the treatment of several diverse disorders that are characterized by accelerated bone loss. Osteoblasts orchestrate bone degradation by expressing the receptor activator of NF‑κB ligand (RANKL), however they additionally protect the skeleton by secreting osteoprotegerin (OPG). Therefore, the relative concentration of RANKL and OPG in bone is a key determinant of bone mass and strength. The current study demonstrated that gallium nitrate (GaN) is able to counteract bone loss in an experimental model of established osteoporosis. Ovariectomized (OVX) rats exhibited significantly increased bone mineral density following GaN treatment for 4 and 8 weeks by 19.3 and 37.3%, respectively (P

Concrete-polymer composites (CPC) pose a major concern of construction industry in recent years. The use of polymer in concrete has long been proven successful due to its good compatibility and the improvement it makes to the concrete. This overview summarizes status of research and applications of CPC in China within the past 3 years, i.e. the influence of polymer on early hydration of cement, the interaction between polymer and cement, and the applications of CPC in waterproofing materials, pavement, repairing materials and so on.

Malignant gliomas are a common type of primary tumor of the central nervous system. In spite of current intensive therapy, the prognosis of patients with malignant glioma remains poor, hence the development of novel therapeutic modalities is necessary. Cell apoptosis is a frequent target in the development of anti‑cancer drugs. Fatsioside A, a novel baccharane‑type triterpenoid glycoside, is extracted from the fruits of Fatsia japonica. Previous studies have shown that Fatsioside A induces growth inhibition, cell cycle arrest and apoptosis in C6 rat glioma cells and U251 human glioma cells. However, to the best of our knowledge, no detailed studies have reported its effect on U87MG glioma cells and its exact mechanisms remain unknown. In the current study, the growth inhibitory effect of Fatsioside A on U87MG cells was evaluated and the underlying molecular mechanisms were explored. Through the use of flow cytometry and a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, it was determined that Fatsioside A markedly inhibits the growth of U87MG cells. Mechanistic studies demonstrated that Fatsioside A induces growth inhibition of U87MG cells via the induction of endoplasmic reticulum (ER) stress, which was supported by the upregulation of ER stress markers, including elevated levels of phosphorylation of PERK and eIF2α, the increased expression levels of CHOP and the accelerated cleavage of caspase‑4. The downregulation of CHOP via CHOP‑specific siRNA reduced the growth‑inhibitive effect of Fatsioside A on U87MG cells, further confirming the role of the ER stress response in mediating Fatsioside A‑induced growth inhibition. In conclusion, Fatsioside A inhibits glioma cell growth via the induction of ER stress‑mediated apoptosis. This may provide a molecular basis for the development of Fatsioside A into a drug candidate for the treatment of malignant glioma.

Pial arteriovenous fistula (AVF) is an extremely rare intracranial vascular lesion. The pediatric type of AVF has a high percentage of varix, leading to mass effect with symptoms. We report a 12-year-old boy who was admitted due to sudden confusion and urinary incontinence. Computed tomography, magnetic resonance imaging, and magnetic resonance angiography (MRA) confirmed the diagnosis of congenital pial AVF. Digital subtraction angiography (DSA) revealed the lesion originating from the left middle cerebral artery and draining into the superior sagittal sinus. The AVF was successfully obliterated with six microcoils and 2.5-mL ethylene vinyl alcohol copolymer using a middle cerebral artery approach. This patient was discharged without neurologic deficits. The AVF became smaller and ultimately disappeared on the DSA and MRA at follow-up.

By multiple realignments of density matrices, we present a new separability criterion for the multipartite quantum state, which includes the computable cross-norm or realignment criterion and the multipartite partial realignment criterion as special cases. An example is used to show that the new criterion can be more efficient than the corresponding multipartite realignment criteria given in Horodecki et al. (Open Syst Inf Dyn 13:103---111, 2006) and Shen et al. (Phys Rev A 92:042332, 2015).

From the Maxwell equation, the method of symplectic finite-difference time-domain is applied in analyzing one-dimensional plasma photonic crystal. The propagation process of electromagnetic pulse in one-dimensional vacuum plasma photonic crystal structure is simulated by symplectic algorithm discrete in 2nd order time 2nd order space (T2S2), and 2nd order time 4th order space (T2S4) respectively. Then, from the perspective of frequency domain, the reflection coefficient of the plasma–vacuum photonic crystals is analyzed. The results show that the symplectic finite-difference time-domain method is accuracy and correctness. In the end, the filter characteristics of the plasma photonic crystals (PPCs) are analyzed in different thickness of plasma.

The development of BIM in China is still at the primary stage. The scope of application is mainly limited within the design phase and building a three-dimension model (3D), which is far away from what is expected. Based on the present situation, the paper analyzes the application process of BIM at the design phase, and puts forward the reason for optimizing the design process, then builds the new design process.

There are many participants in one construction project, however there is no direct contractual relationship between some of them and lots of disputes, claims, problems occur on organization interface, which result in great waste and low efficiency. BIM (Building information modeling) is an innovation idea and benchmarking technology which has great impact on organization and can improve the collaborative efficiency of all construction organizations. The present problems in traditional construction project organization interface management are analyzed firstly. And then, value of BIM which is applied to solve the present problems in organization interface management is analyzed and summarized. Finally, project collaborative environment logic structure at the base of BIM is constructed to achieve maximum performance of project management.

This thesis constructs the dynamical model of the imbalance-misalignment coupling faults and the finite element model of the rotor system which are supported by rolling element bearing. It analyses the impacts from the coupling faults to the system on the basis of nonlinear finite element method, dynamic theory and Newmark-beta numerical integration method. It also studies the influence of the unbalance, misalignment and coupling faults to the system by applying the dynamic response chart and time-frequency properties. The study shows that there exist unstable high and low harmonic components, the unbalanced signal overshadowed by misalignment. It also discovers that besides the working frequency, there also exist tow times frequency and other high doubling components on the response spectra with two times frequency for the most. All those study results provide some theoretical reference for the fault diagnosing of the rotor bearing system, the vibration control and the stability research.

Characteristic signals in rotating machinery fault diagnosis with the issues of complex and difficult to deal with, while the use of non-linear manifold learning method can effectively extract low-dimensional manifold characteristics embedded in the high-dimensional non-linear data. It greatly maintains the overall geometric structure of the signals and improves the efficiency and reliability of the rotating machinery fault diagnosis. According to the development prospects of manifold learning, this paper describes four classical manifold learning methods and each advantages and disadvantages. It reviews the research status and application of fault diagnosis based on manifold learning, as well as future direction of researches in the field of manifold learning fault diagnosis.

In modern times, information technology developes very quickly. Architecture engineering construction industry has gradually been revolutionized from traditional ways to technology-based methods. As the engineering construction project is very complex ,advanced tools are required to assist finishing a project. Building information modeling is disseminated to construction industry ,as an instrument to help collaboration and co-working. The practical effectiveness of BIM is mainly in architecture design, while BIM can be used as a tool in other parts of construction industry such as virtual construction ,time-dependent control and maintainance management and even the lifecycle management.This paper mainly presents five main parts and functions designed of information system based on BIM, and analyses the strengths of the system .It aims to demonstrate how engineering project overcome traditional barriers and physical distribution with the development of information technology across the whole construction lifecycle.

In this paper, we present some lower bounds for the Perron root of a symmetric nonnegative matrix, which are then applied to give the lower bounds of the Perron root of a general nonnegative matrix. These bounds improve the corresponding ones in [3] and [5]. Numerical examples are supplemented to illustrate the effectiveness of the presented bounds. Mathematics subject classification (2010): 15A18, 15A57, 65F15.

In strip tandem rolling process, there is always deviation between the center line of the strip and the assumed center line, which is called running deviation. In this thesis, based on the actual running deviation data of some aluminum strip rolling industry, we analyzed their chaos and fractal character, proposed one improved pattern classification based on the fuzzy c-average clustering, on basis of this method classified running deviation pattern, constructed adding weight zero-order local prediction method of strip truning deviation signal. After the s actual data test, the forecasting result achieves the desired accuracy.

It is common for the imbalance-crack coupling fault in rotating machinery, while the crack information is often overshadowed by unbalanced fault information, which is difficult to extract the crack signal. In order to extract the crack signal of the imbalance-crack coupling fault, and realize the fault diagnosis, the paper mainly analyzes its mechanical properties, and then use wavelet packet to de-nosing, decomposing and reconstructing the acquisition of vibration acceleration signal, and then analyzing the characteristics of frequency domain of the fault signal by using the energy spectrum. So the experiment proved that analyze and dispose the acquisition of the fault signal by using the method of the energy spectrum and the wavelet packet, which can effectively distinguish between the crack signal and unbalanced signals in imbalance-crack coupling faults .It also can provide some reference for the diagnosis and prevention for such fault.

Vibration signals of rotating machinery on the base are very weak and always buried in noisy noise; the common denoising methods have become powerless. It presents an ensemble empirical mode decomposition method (EEMD) that is used to denoise for the base vibration signal, which not only to overcome the problem of mode mixing, but also to avoid the selection of wavelet basis function and decomposition level of the problem. Experimental results of simulation and measured data show that EEMD method can effectively reduce the base vibration signal noise, which is better than the wavelet and EMD denoising method.

In signal denoise method to nonlinear time series based on principle manifold learning, reduction target dimension is chosen at random, which cause low efficiency. Local low dimensional manifold is obtained by the eigenvalue decomposition to the covariance matrix, but covariance belongs to the second order statistics and cannot reflect the nonlinear essential structure of signal, these reduce denoise efficiency and effect. In order to solve these problem, a new denoise algorithm based on the higher order cumulant and local tangent space mean reconstruction is proposed in this reserch. First, the signal's intrinsic dimension is obtained as dimension of reduction targets by maximum likelihood estimation. And then making use of restraining character to colored noise of high order cumulan,covariance matrix is constructed by high order cumulant function instead of second order moment function. The data outside intrinsic dimension space will be regarded as noise signal to be eliminated. Finanly the process of global array by affine transformation will be replaced by mean reconstruction,the data after denoise may be obtained in the inverse process of the phase space reconstruction. The effectiveness of the algorithm is verified through the denoise experiment in fan vibration signal with noise.

More and more attention has been paid to hospital facilities since modern pandemics have emerged such as SARS and avian influenza. Energy consumption by buildings accounts for 20-40% of energy use in developed countries, so many global organizations make efforts to develop sustainable technologies or materials to create a sustainable environment, and to reduce energy consumption when renovating building. Therefore, maintaining high standards of hygiene and reducing energy consumption has become the major task for hospital buildings. This study develops an integrated decision support system to assess existing hospital building conditions and to recommend an optimal scheme of sustainable renovation actions, considering trade-offs between renovation cost, improved building quality, and environmental impacts. A hybrid approach that combines the A* graph search algorithm with genetic algorithms (GA) is used to analyze all possible renovation actions and their trade-offs to develop the optimal solution. A simulated hospital renovation project is established to demonstrate the system. The result reveals the system can solve complicated and large-scale combinational, discrete and determinate problems such as the hospital renovation project, and also improve traditional building condition assessment to be more effective and efficient.

In the rolling process, deviation is the phenomenon that the strap width direction's centerline deviates from rolling system setting centerline,serious deviation will cause product quality drop and rolling equipment fault. This paper has established the finite element model to the hot tandem rolling aluminum strap, analyzed the strap’s deviation rule under four kinds of incentives,obtained the neural network predictive model and the control policy of the tail deviation.The result to analyze a set of fact deviation data shows this method may control tail deviation in preconcerted permission range.

Due to the great negative impact, the construction industry needs to undergo a paradigm shift from traditional construction to sustainable construction. To reach the goal of sustainable development, the construction industry needs to intensify its efforts to move to a knowledge intensive mode. Based on the analysis of e-Cognos and the concept of ontology, this paper proposes that e-Cognos ontology can be applied in the development of sustainable construction process ontology, which is a key part of knowledge management system (KMS). Following this, the application process of ontology-based KMS is analyzed using IDEF0 modeling method. Finally, this paper analyzes interorganizational collaboration model in sustainable project.

The construction, operation and demolition of building have tremendous impacts on the global energy and environment. However, initial construction costs are overly concerned in traditional construction projects and the economic, social and environmental impacts are neglected, which is a crucial barrier to the promotion of the sustainable construction. Through borrowing the theory from manufacturing industry, this paper analyzed the concept of lean construction, and combined the advantage of lean thinking with the sustainable development, promoting the sustainability and maximum value of construction projects besides the realization of three main objectives - the quality, schedule, cost of the construction project. Then, this article introduced the implementation of lean construction in the sustainable construction projects based on the view of transfer, flow, and value, and finally constructed the building objectives system which is composed of the minimum cost, the condensed duration, the superior quality and the sustainability of the construction.

In order to better identify the fault of bearing,one new fualt diagnosis method based on supervised Linear local tangent space alignment (SLLTSA) and support vector machine (SVM) is proposed..In this methd, the supervised learning is embedded into the linear local tangent space alignment algorithm,making full use of experience category information for fault feature extraction, and then using linear transformation matrix to fast process the new monitoring data, finally distinguishing fault status of the incremental data by nonlinear SVM algorithm. The experiment result for roller bearing fault diagnosis shows that SLLTSA-SVM method has better diagnosis effect than related unsupervised methods.

To enhance the effect of fault diagnosis, a new fualt diagnosis method based on supervised incremental local tangent space alignment (SILTSA) and support vector machine (SVM) is proposed. The supervised learning approach is embedded into the incremental local tangent space alignment algorithm, to realize fault feature extraction and new data processing for equipment fault signal, and then correctly classify the faults by non-linear support vector machines. The experiment result for roller bearing fault diagnosis shows that SILTSA-SVM method has better diagnosis effect to related methods

In the noise reduction algorithm based on manifold learning, phase space data may be distorted and reduction targets are chosen at random, it made efficiency and effect of noise reduction lower.To solve this problem, a improved noise reducation method (local tangent space mean reconstruction) was proposed.The process of global array by affine transformation will be replaced with mean reconstruction,and the intrinsic dimension was estimate as dimension of reduction targets by using maximum likehood estimation method, the data in addition to intrinsic dimension space will be eliminated.Noise reduction experiment to fan vibration signal with noise shows this method had better noise reduction effect.

Locally linear embedding (LLE) algorithm is an unsupervised technique recently proposed for nonlinear dimension reduction. In this paper,LLE manifold learning algorithm is introduced into the field of equipment fault diagnosis firstly, a method of the fault diagnosis based on LLE_KFDA is proposed. By LLE algorithm, original sample data is directly mapped to its’ intrinsical dimension space,which data still keep primary nonlinear form. then via kernel fisher discriminant analysis(KFDA), the characteristics data in intrinsical dimension space are mapped into knernel high-dimensional linear space,and then different fault data are discriminated based on a criterion of between-class and insid-class deviatione ratio maximum. LLE_KFDA algorithm is based on original data, avoided from fall of pattern recognition ability which caused by inappropriate or blind choice of the feature parameters in the traditional fault diagnosis method.The experiment to fault diagnosis of rolling bearing shows this method can effectively identify the equipment fault pattern, diagnostic result is good.

Background Evaluation of fetal central nervous system (CNS) agenesis by ultrasonography (US) is frequently limited, but magnetic resonance imaging (MRI) has its own advantages and is gaining popularity in displaying suspected fetal anomalies. The purpose of this study was to explore the value of MRI in detecting fetal CNS agenesis. Methods Thirty-four women (aged from 22 to 35 years, average 27 years) with complicated pregnancies (16- 39 weeks of gestation, average 30 weeks) were examined with a 1.5 T superconductive MR unit within 24 hours after ultrasonography. Half-Fourier acquisition single-shot turbo spin-echo (HASTE) T2-weighted imaging (T2WI) sequence were performed in all patients, and fast low angle shot (FLASH) T1-weighted imaging (T1WI) sequence were applied sequentially in seven of them. Comparison of the results was made between the MRI and US findings as well as autopsy or postnatal follow-up MRI findings. Results The gyrus, sulcus, corpus callosum, thalamus, cerebellum, brainstem, and spinal cord of fetus were shown more clearly on T2-weighted MR images than on T1weighted MR images. MRI corrected the diagnosis of US in 10 cases (10/34, 29.41%) and the diagnosis was missed only in 1 case (1/34, 2.94%). Conclusion MRI has advantages to US in detecting fetal CNS anomalies and is a supplement to US in complicated pregnancies. Chin Med J 2006; 119(15): 1272-1277

Objective The aim of this study was to determine differences in diameter of cochlear nerves (CN) among three measurement points at the midpoint of the internal auditory canal (IAC), IAC fundus and cochlear aperture, and to evaluate whether nerve size varies with age. Methods A total of 336 normal-hearing ears of 201 children were assessed, who were underwent 3D-Fiesta sequence scanning of inner ear. All subjects were divided into 12 groups at one year interval. The diameter measurements of CN were obtained in the midpoint of the IAC, IAC fundus and cochlear aperture respectively on the axial and oblique sagittal images of 3.0-T MRI. SPSS 18.0 statistics software was applied for data analysis, and all of the data showed a normal distribution and expressed in x ¯ ± s . Results The diameters of normal-hearing children's CN at the midpoint of the IAC, IAC fundus and cochlear aperture were respectively: 1.12 ± 0.08 mm, 1.05 ± 0.06 mm, 0.87 ± 0.14 mm, and there were significant differences among the three measuring points ( F = 527.57, p p > 0.05) in age groups, gender and sides ( p > 0.05), and there was no correlation between the diameters of normal children's CN and age ( r is −0.129, 0.128 and −0.113, respectively). Conclusion The diameters of normal-hearing children's CN change with different points of the internal auditory canal, of which the maximum value is in the midpoint of the IAC, followed by the IAC fundus, and the cochlear aperture is at the minimum; moreover the normal size doesn’t change with age.

To study the feasibility of endolymphatic visualization and the diagnosis of Meniere's disease by applying intratympanic gadolinium administration through the tympanic membrance and three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI). To study the relationship between the endolymphatic hydrops visualized by MRI and audio-vestibular functional tests, such as pure tone audiometry (PTA), electrocochleography (EcoG), caloric test and vestibular evoked myogenic potential (VEMP).With a three Tesla magnetic resonance imaging (MRI) unit, 3D-FLAIR imaging was performed 24 hours after intratympanic gadolinium through the tympanic membrance in 32 patients with clinically diagnosed unilateral Meniere's Disease. We visualized the enhanced imaging of perilymphatic space in bilateral cochlea, vestibular and (or) canal, scoring scala tympani and scala vestibule of bilateral cochlear basal turn respectively and measuring the developing area of bilateral vestibule and the signal intensity ratio (SIR) between the vestibule and the brain stem subjectively. PTA, EcoG, caloric test and VEMP were performed. The relationship between the endolymphatic hydrops visualized by MRI and audio-vestibular functional tests were studied.The gadolinium appeared in almost all parts of the perilymph in cochlea, vestibular and (or) canals in all 32 patients' inner ears, so the endolymphatic space was clearly shown on 3D-FLAIR imaging. The scala vestibuli score value between the affected side and the healthy side were statistically significant (Z = 4.309, P0.05) . The developing vestibular area between the affected side and the healthy side [(6.04 ± 2.89) mm(2), (8.28 ± 3.04)mm(2)] were statistically significant (t = 3.322, P0.05) . Abnormal vestibular evoked myogenic potentials were significantly correlated with the developing vestibular area of the affected side (F = 11.96, P0.05) . Abnormal electrocochleography were significantly correlated with scala vestibuli score value of cochlear basal turn in the affected side (Z = 3.17, P0.05) . No significant correlation was found between the scala vestibuli score value or the developing vestibular area and caloric test or PTA findings.3D-FLAIR MRI with intratympanic gadolinium injection through the tympanic membrance can discriminate the border between the perilymph and the endolymph and show endolymphatic hydrops. This method may provide radiographic reference for the diagnosis of Meniere's disease. The results of VEMP and electrocochleography might have appropriate correlation with degree of vestibular and cochlear hydrops.

HIV is a neurotropic virus which can cause brain white matter demyelination, gliosis, and other pathological changes that appear as HIV encephalitis or AIDS dementia. The purpose of this study was to investigate the change of the diffused condition of water molecules in brain white matter in early acquired immune deficiency syndrome (AIDS) patients using MR diffusion tensor imaging (DTI).DTI examinations were performed on a Siemens 3.0T MR scanner in 23 AIDS patients with normal brain appearance by conventional MRI and 20 healthy volunteers as the control group. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were measured in nine regions; corpus callosum (CC) knee, CC body, CC splenium, periventricular white matter, frontal lobe white matter, parietal lobe white matter, occipital lobe white matter, and the anterior and posterior limbs of the internal capsule. The mean FA and ADC values from each region were compared in three groups: the symptomatic, asymptomatic and the control.The mean FA values were significantly lower and the mean ADC values were significantly higher in all nine regions in patients in the symptomatic group than in the asymptomatic and control group patients. In the asymptomatic group, the mean FA values were significantly lower and the mean ADC values were significantly higher at the CC knee, CC body, CC splenium, periventricular white matter, frontal lobe white matter and parietal lobe white matter, than in the control group. There were no significant differences at other regions between the two groups.The diffused changes of water molecules in brain white matter in AIDS patients are related to brain white matter regions. DTI examination can detect the brain white matter lesions early in AIDS patients.

This paper proposed a complete solution of UHF RFID reader system based on S3C2440 microprocessor and AS3992 UHF Reader chip. By designing the automatic gain control(AGC) circuit and the antenna impedance automatic matching circuit, the transmit power is up to 33dBm and the receiver SNR is improved at the same time. The reader system is transplanted into the embedded Linux OS which greatly facilitates the system development and maintenance. Practice shows the RFID reader implemented in this paper has achieved high-speed identification of ISO18000-6C RFID tags and stable reading range up to 10 meters.

To evaluate the preoperative pain degree of lumbar intervertebral disc herniation and analyzed its reason.From January 2002 to December 2008,265 patients with lumbar intervertebral disc herniation were operated by single segment, of which site in L4,5 was 128 cases and in L5S1 was 137 cases. There were 162 males and 103 female, ranging in age from 21 to 78 years, with an average of 46.3 years. Oswestry index of all patients was observed before operation. The patients were divided into five groups based on Carragee system (according to degree of nucleus pulposus herniation and degree of fibrous ring cleavage to group, prolapse and liberation of nucleus pulposus with small ring cleavage was group I; prolapse and liberation with large ring cleavage was group II; contained fragment with integrated fibrous ring was group III; no contained fragment with integrated fibrous ring was group IV; calcified nucleus pulposus with degenerative fibrous ring was group V). The associativity between five types of lumbar intervertebral disc herniation and preoperative pain degree was analyzed.The preoperative pain in group I and group II was more severe than that of other groups (P0.01). The preoperative pain in group II was more severe than that of group I (P0.01).Nucleus pulposus can migrated into the spinal canal and will aggravate the nerve root pain if lumbar intervertebral disc herniation accompanies with fibrous ring cleavage; and freed materials can aggravate the nerve root pain by the chemical factor.