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This paper presents three strategies for modeling the regional empirical T m (the weighted mean temperature of the atmosphere) to obtain more accurate determinations in a regional empirical model that is better adapted to the geographical and climatic characteristics of the applied area. The proposed models utilize data from four radiosonde stations in Guangxi, at Nanning, Guilin, Wuzhou and Baise, over an 11 month period (from Jan. to Nov. of 2011). The experimental results demonstrated the following: (1) there is no significant difference between monthly and annual regression results at each site; (2) it is more reasonable and feasible to use the proposed regional Hybrid model for the area far away from the radiosonde site; (3) from the analysis of the possible temperature conditions, the precision of the proposed regional Hybrid model is higher than that of the well-known Bevis formula and of some other existing models and can reach an accuracy within 1 mm for the GPS-derived PWV estimates for the applied region.

Focal adhesion kinase (FAK) is known to promote the proliferation, migration and survival of synovial cells and plays an important role in the occurrence, development and pathological process of rheumatoid arthritis (RA). The aim of the present study was to observe FAK changes in synovial cells of rats with collagen-induced arthritis (CIA) and after intervention with disease modifying anti-rheumatic drugs (DMARDs) alone or in combination in a CIA female SD rat model induced by collagen type II. The rats were randomized to 8 groups: normal control group, CIA model control group, methotrexate (MTX, 0.9 mg/kg/w) group, cyclophosphamide (CTX, 24 mg/kg/3 w) group, leflunomide (LEF, 1.2 mg/kg/d) group, MTX + CTX group, LEF + CTX group, and MTX + LEF group. They were intervened with DMARDs alone or in combination for six weeks. The experiment lasted a total of 9 weeks in vivo. Articular inflammation was measured during the process of drug intervention in terms of the degree of swelling degree in the right hind foot using a venire caliper. All animals were sacrificed by breaking the neck after 9 weeks. Then, the ankle was fixed, decalcified, embedded, and HE stained, and prepared into slices to observe pathological changes in the synovial tissue. FAK expression in synovial cells was assayed by immunohistochemistry and the mean optical density (OD) value was measured using the HPIAS-2000 image analysis system. It was found that FAK expression was negative in normal control group, positive in CIA model control group, and decreased in the three DMARD combination treatment groups significantly as compared with that in the three single-drug groups (P < 0.05). FAK expression in LEF + CTX group or MTX + CTX group decreased more significantly than that in MTX + LEF group (P < 0.05), and there was no statistically significant difference between LEF + CTX and MTX + CTX groups. The arthritis index and pathological change in the synovial tissue in LEF + CTX group or MTX + CTX group were improved more significantly than those in MTX + LEF group or single-drug groups. Our results showed that FAK expression was positive in CIA rats, indicating that it played an important role in the pathogenesis of RA, and that intervention with DMARDs could reduce the FAK expression in synovial cells of CIA rats. We hope these findings would contribute to the treatment of RA and other rheumatic diseases by reducing adhesion, proliferation and migration of synovial cells and inhibiting the over-expression of FAK.

Data of LAI(Leaf Area Index) are needed to study characteristics of photosynthesis and evaporation by canopy of plant community. The indirect method—Imaging Digital Canopy, based on “gap-fraction” process, was described in this paper. By study in various communities about 9 measuring spots, it showed characteristics of community such as LAI, radiation transmission, extinction coefficient. LAI of Vatica hainanensis forest was measured according to height of community in different developing stage. The technique to minimize error about the Digital Plant Canopy Imager CI110 was mentioned. It was discussed that LAI of Vatica hainanensis forest was lower than that of typical rainforest. It also certified that LAI of seashore rain forest was lower than that of typical mountain rainforest. And LAI correlation of various vegetations was also mentioned. The result should supply scientific basis to study on air environmental effects of tropical seashore vegetation, especially in O2/CO2exchange, water recycle and water-lose, solar energy utilization efficiency.

Normal mode analyses are made for methyl palmitate molecule having all-trans or conformational disorders around the ester head group, in order to explain characteristic observed frequency shifts in the wagging progressive region between all-trans and disorder chains in triglyceride molecules. It was found that one gauche conformation at C(alpha)-C(beta) position and 90 degrees rotation of the ester head group in an alkyl chain produce frequency shifts for twisting mode as observed. For wagging modes, contamination of the disorders around the head group makes assignments change and apparent frequency shifts occur.

An IR study of the conformational disorder in the part of the hydrocarbon chain nearest the ester group in gel-phase lipid bilayers is presented. The infrared method for determining the conformation of the CH2−CH2 bond attached to the ester group is discussed and applied to a number of representative gel-phase 1,2-diacylphosphatidylcholine fully hydrated dispersions, including symmetric and mixed-chain PCs in their gel and subgel phases. The effect on chain conformation of the headgroups PC, PE, and PA- was explored. Only two conformations of the alkyl chains were found: a planar (all-trans) chain and a nonplanar chain that is all-trans except for the CH2−CH2 bond nearest the ester group. Concentrations of the two conformers were also determined. The overall concentration of the planar form always exceeds 50% but varies significantly depending on the lipid involved. In two cases, the concentration of the planar conformer was estimated for both the SN1 and SN2 chains.

In the paper, the research present situation and development in the wavelet neural network model and a novel learning algorithm for wavelet neural network based on extended Kalman filter are discussed. Based on combining the exceptional property of localization of the wavelet transform and characteristics of self-learning of neural networks, the non-line time series model and network architecture model which combines affine transform with revolving transform is discussed. A novel learning algorithm for wavelet neural network based on extended Kalman filter is proposed to predict the deformation of structure. In comparison with the WNN algorithm, the EKF learning algorithm has improved convergence and can provide much more accuracy learning results.

Systematic errors, such as multipath and residual atmospheric errors in GPS double difference carrier phase observations, are the main error sources for high precision GPS applications. The complicated properties of systematic errors limit the modelling and mitigation of these errors when parametric models are used. In this paper, a new approach based on wavelet analysis is developed to tackle them. Wavelet transform is used as a tool to separate systematic errors from the signal. The signal here is double differential phase observation, which is an input for wavelet transform system. Through multi-step decomposition for original double differential observation, systematic errors identity is exhibited at a certain scale in the decomposition and the double differential observation is then reconstructed by a filtering to the signal with systematic errors eliminated. The newly formed observation is then used as the input for baseline adjustment unit to achieve desired positioning efficiency. Experiment and analysis is conducted to show the applicability of the proposed approach.

A pyramid approach for remote sensing image registration based on mutual information and grey relational analysis is presented. The methodology applies edge information of image extracted using grey relational analysis and combines with mutual information regarding as similarity measure. First, the image pyramid is constructed by wavelet transform, and then coarse-to-fine multi-resolution search approaches have been put forward to increase accuracy and efficiency. An exhaustive search algorithm is applied at the coarsest level of the image pyramid. Registration at higher levels can be performed with the result at the pervious level serving as the initial condition. The effective and exact matching results can be obtained by applying the algorithm to remote sensing image registration.

The characteristics of three GPS kinematical data processing models, Least Square, Kalman filtering, are discussed and their advantages and disadvantages are compared. With observational data and pertinent data processing software, the applicable condition, context and effect of the three models are experimented. Results show that when the mobile platform is in uniform motion, the accuracy of the three models are almost equal; when the mobile platform is in stochastic acceleration, the accuracy of new filtering model is superior to that of LS, and that of Kalman filtering is the worst.

The least-square ambiguity decorrelation adjustment method(LAMBDA)is one of the most appropriate techniques for GNSS carrier phase ambiguity resolution. The LAMBDA method is an algorithm for searching the most likely integer ambiguity combination. Based on a floating least-squares estimation of integer ambiguities, it minimizes the quadratic norm of the residuals. In the paper the use of known base vector length during ambiguity resolution of arrier phase measurements is considered. The comparisons of correct ambiguity resolution probabilities in the cases when the base vector length information is used and unused are given.

To Compare the curative effects between titanium mesh coated with or without silk fibroin and in the treatment of larger trachea circumferential defects. To explore the merits of titanium mesh coated with silk fibroin in promoting mucous healing and decreasing related complications.Twenty-five New Zealand white rabbits were chosen , divided randomly as follows: group one: titanium mesh coated with silk fibroin (n = 12), group two: pure titanium mesh without silk fibroin (n = 12); Titanium mesh coated with silk fibroin and those titanium without silk fibroin were embedded in the anterior of 7-12th tracheal rings respectively, in 2 weeks we removed the anterior and lateral wall of 7-12th tracheal rings about 8 mm x 6mm (more than half ring) and used the two different materials to reconstruct tracheal defects. All these rabbits were euthanized in 4, 8 and 12 weeks and tracheal CT scan, tracheal endoscopy, histopathological examination and scanning electron microscopic examinations were performed. All complications such as death, local inflammation, tracheal stenosis were documented. Group three, leave one normal rabbit as controlled study , removed the anterior and lateral wall of 7-12th tracheal rings, and histopathological examination, scanning electron microscopy were performed as controlled study.The CT scan, tracheal endoscopy of those with silk fibroin showed there was no apparent tracheal stenosis. Histopathological examination showed there was no obvious granulation tissue and scar. The mucous membrane and cilia grow normally. The silk fibroin was not entirely absorbed and the remains showed good biocompatibility. The scanning electron microscopy showed that the cilia grew better and more orderly than that of group two, and in 12 weeks, the cilia became normal. In group two, there were 5 rabbits died in succession from suffocation in 4, 5, 7, 17, 60 days after surgery. All rabbits had local or general subcutaneous emphysema. The CT scan, tracheal endoscopy and pathological examination showed that there were apparent granulation tissue, scar hypertrophy, and tracheal stenosis. The mortality of group two (41.7%) for suffocation compare to that of group one (0), the incidence rate of subcutaneous emphysema in group two (100%) to that of group one (25.0%) and the average cross section stenosis area in group two (18.15 +/- 7.85) mm2 to that of group one (3.15 +/- 1.58) mm2, there are significant statistically differences in these postoperative complications (P0.05) and stenosis degree (P0.05) between the two groups. In addition, there was one rabbit died of diarrhea in each group except group three.Silk fibroin and titanium mesh coated with silk fibroin showed good biocompatibility. Titanium mesh coated with silk fibroin used in tracheal reconstruction of rabbits can promote agglutination of mucous membrane and decrease postoperative complications, such as subcutaneous emphysema, tracheostenosis. It may be a prospective biomaterial which can be used in clinical circumferential trachea defect reconstruction.