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In this study, a total of 177 flexural experimental tests of corroded reinforced concrete (CRC) beams were collected from the published literature. The database of flexural capacity of CRC beam was established by using unified and standardized experimental data. Through this database, the effects of various parameters on the flexural capacity of CRC beams were discussed, including beam width, the effective height of beam section, ratio of strength between longitudinal reinforcement and concrete, concrete compressive strength, and longitudinal reinforcement corrosion ratio. The results indicate that the corrosion of longitudinal reinforcement has the greatest effect on the residual flexural capacity of CRC beams, while other parameters have much less effect. In addition, six available empirical models for calculating the residual flexural strength of CRC beams were also collected and compared with each other based on the established database. It indicates that though five of six existing empirical models underestimate the flexural capacity of CRC beams, there is one model overestimating the flexural capacity. Finally, a newly developed empirical model is proposed to provide accurate and effective predictions in a large range of corrosion ratio for safety assessment of flexural failure of CRC beams confirmed by the comparisons.

Using a hybrid simulation approach that combines a finite difference method with a Brownian dynamics, we investigated the motion of charged polymers. Owing to the fact that polymer-solution systems often contain a large number of particles and the charged polymer chains are in a state of random motion, it is a time-consuming task to calculate the electrostatic interaction of the system. Accordingly, we propose a new strategy to shorten the CPU time by reducing the iteration area. Our simulation results illustrate the effect of preset parameters on CPU time and accuracy, and demonstrate the feasibility of the “local iteration” method. Importantly, we find that the increase in the number of charged beads has no significant influence on the time of global iterations and local iterations. For a number of 80 × 80 × 80 grids, when the relative error is controlled below 1.5%, the computational efficiency is increased by 8.7 times in the case that contains 500 charged beads. In addition, for a number of 100 × 100 × 100 grids with 100 charged beads, the computational efficiency can be increased up to 12 times. Our work provides new insights for the optimization of iterative algorithms in special problems.

Based on the empirical electronic theory of solids and molecules (EET), the actual model for unit cell of cementite (θ-Fe3C) was built and the valence electron structures (VES) of cementite with specified site and a number of Fe atoms substituted by alloying atoms of M ( M=Cr, V, W, Mo, Mn ) were computed by statistical method. By defining P as the stability factor, the stability of alloyed cementite with different numbers and sites of Fe atoms substituted by M was calculated. Calculation results show that the density of lattice electrons, the symmetry of distribution of covalent electron pairs and bond energy have huge influence on the stability of alloyed cementite. It is more stable as M substitutes for Fe2 than for Fe1. The alloyed cementite is the most stable when Cr, Mo, W and V substitute for 2 atoms of Fe2 at the sites of Nos. 2 and 3 (or No. 6 and No. 7). The stability of alloyed cementite decreases gradually as being substitutional doped by W, Cr, V, Mo and Mn.

In this study, we used the multi-resolution graph-based clustering (MRGC) method for determining the electrofacies (EF) and lithofacies (LF) from well log data obtained from the intraplatform bank gas fields located in the Amu Darya Basin. The MRGC could automatically determine the optimal number of clusters without prior knowledge about the structure or cluster numbers of the analyzed data set and allowed the users to control the level of detail actually needed to define the EF. Based on the LF identification and successful EF calibration using core data, an MRGC EF partition model including five clusters and a quantitative LF interpretation chart were constructed. The EF clusters 1 to 5 were interpreted as lagoon, anhydrite flat, interbank, low-energy bank, and high-energy bank, and the coincidence rate in the cored interval could reach 85%. We concluded that the MRGC could be accurately applied to predict the LF in non-cored but logged wells. Therefore, continuous EF clusters were partitioned and corresponding LF were interpreted, and the distribution and petrophysical characteristics of different LF were analyzed in the framework of sequence stratigraphy.

Wave velocities in haloanhydrites are difficult to determine and significantly depend on the mineralogy. We used petrophysical parameters to study the wave velocity in haloanhydrites in the Amur Darya Basin and constructed a template of the relation between haloanhydrite mineralogy (anhydrite, salt, mudstone, and pore water) and wave velocities. We used the relation between the P-wave moduli ratio and porosity as constraint and constructed a graphical model (petrophysical template) for the relation between wave velocity, mineral content and porosity. We tested the graphical model using rock core and well logging data.

Commercial grade-70 tire cord steel was microalloyed with V and N to explore the possibility of substituting V for C and the effect of V and N on cementite dissolution during cold drawing process. Tensile strength, elongation and torsion laps of cold-drawn wires were determined. Microstructures of secondary phases were studied by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). Saturation magnetization was measured by using a vibrating sample magnetometer (VSM) to evaluate cementite dissolution during cold drawing process. Experimental results showed that with the increase of V content, tensile strength increased, elongation slightly decreased, and the torsion laps of the cold-drawn wires decreased. Results also showed that with the increase of N content, a peak (increasing first and then decreasing) appeared in the tensile strength graph, and an increase of elongation and a decrease of torsion laps of the cold-drawn wires occured. N is soluble in ferrite when its content is low. The increase in the content of N to 82 × 10 −6 will result in the precipitation of the V-containing secondary phases. Also, cementite tended to be stable during cold drawing process with the increase of V and N contents. Grade-80 tire cord steel can be replaced by grade-70 tire cord steel microalloyed with 0.086 mass% V.

Heading date is a key determinant of regional and seasonal adaptation in rice (Oryza sativa L.). A minor-effect quantitative trait locus (QTL), QTL for D ays t o h eading 12a (qDTH-12a), with unknown genetic action was previously coarsely detected in a recombinant inbred line population. The study reported here was designed to better define the qDTH-12a locus (designated as DTH12) in advanced segregating populations. DTH12 was initially verified in chromosome segment substitution line CSSL84. A CSSL84/Asominori//Asominori BC4F2 population was then developed, and a near-isogenic line (NIL), NIL(DTH12), was subsequently selected from this population using marker-assisted tracking that headed 8 days later than Asominori under long-day (LD) conditions but which was not significantly different in heading date in short-day environments. Using 358 Asominori/NIL(DTH12) F2:3 families grown under LD conditions, we were able to initially map DTH12 to a 26-cM interval between markers InDel12-1 and RM6296. F3 individuals heterozygous for the DTH12 regions were then chosen, and 2,388 F4:5 families were used for fine mapping. DTH12 was finally dissected as a single gene and delimited to a 153-kb genomic region with 32 open reading frames. Compared with Asominori, NIL(DTH12) showed reduced transcription of the florigen genes Heading date 3a and RICE FLOWERING LOCUS T 1, suggesting that DTH12 functions as an up-regulator of florigen genes during floral induction under LD conditions. DTH12 was also found to have an important role in rice adaptation and breeding for precise control of seed maturity. These findings provide a firm basis for cloning this minor-effect QTL involved in rice flowering.

Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor for midbrain dopamine (DA) neurons, while the DA neurons in the ventral tegmental area (VTA) is a crucial part of the neural circuits associated with drug addiction. Recently, more and more evidence suggests that GDNF plays an important role in negatively regulating the neuroadaptations induced by chronic exposure to drugs, which was thought to be the neurobiological basis of drug addiction, but the underlying mechanism is still unknown. More recently, the neural cell adhesion molecule (NCAM), which plays an important role in the process of neural plasticity, has been identified as an alternative signaling receptor for GDNF. The purpose of this study was to investigate whether NCAM was involved in the effects of GDNF on the neuroadaptations induced by chronic morphine exposure. Immunostaining results showed that NCAM was widely expressed in the VTA of rats, including all the DA neurons. The results also showed that the phosphorylation of NCAM-associated FAK, but not the total NCAM, was upregulated by GDNF, and this upregulation was inhibited by pre-treatment with the NCAM function-blocking antibody. Moreover, pre-treatment with the antibody could antagonize the effect of GDNF on inhibiting the neuroadaptations induced by chronic morphine exposure, including the decreases of the number and length of neurites and the size of cell bodies of VTA dopamine neurons, as well as the increase of tyrosine hydroxylase in the VTA dopamine neurons. These results suggest that NCAM signaling is involved in the negative regulatory effects of GDNF on chronic morphine-induced neuroadaptations.

We investigated the survival and the possible differentiation fate of the progenitors and immature neurons in the pars compacta of the substantia nigra (SNc) by intranigral injection of a glial cell line-derived neurotropic factor (GDNF) or glial cell line-derived neurotropic factor plus epidermal growth factor (EGF + GDNF) in 6-hydroxydopamine (6-OHDA)-lesioned rats. First, we performed behavioral tests by postural asymmetry and forelimb akinesia on the rats injected with 6-OHDA in striatum at day 7, and selected the qualified model according to the results. Then, intranigral GDNF or EGF + GDNF treatment was administered in the qualified PD model rats. On day 21, behavioral tests were performed with these rats; and then the rats were sacrificed for analyses of β-tubulin isotype-III (Tuj1), nestin, glial fibrillary acidic protein (GFAP), and tyrosine hydroxylase (TH) by immunohistochemistry and Western blotting. The results indicated that GDNF could promote the survival of the progenitor cells and immature neurons in rat SNc following 6-OHDA lesion. Moreover, EGF is capable of enhancing the survival effect of GDNF on the progenitor cells and immature neurons in SNc. On day 21, rapid functional recovery from the lesion-induced behavioral asymmetries was observed in the GDNF or EGF + GDNF-treated rats, and the numbers of TH-positive neurons increased in SNc, suggesting that the rats might generate new dopaminergic neurons. Thus, our study provides the new insight that the progenitors and immature neurons in SNc of 6-OHDA-lesioned rats might be able to differentiate toward the dopaminergic neurons fate subsequent to treatment with GDNF or EGF + GDNF.

Aim: To explore the intracellular mechanisms underlying the survival/differentiation effect of the glial cell line-derived neurotrophic factor (GDNF) on dopamine (DA) cells. Methods: Midbrain slice culture and primary cell culture were established, and the cultures were divided into 3 groups: control group, GDNF group, and the phosphatidylinositol 3-kinase/Akt (PI3-K/Akt) pathway-inhibited group. Then the expression of tyrosine hydroxylase (TH) was detected by immunostaining as well as Western blotting. Results: GDNF treatment induced an increase in the number of TH-immunoreactive (ir) cells and the neurite number of TH-ir cells, as well as in the level of TH expression in cultures (Number of TH-ir cells in the slice culture: control group, 8.76±0.75; GDNF group, 18.63±0.95. Number of TH-ir cells and neurite number of TH-ir cells in cell culture: control group, 3.65±0.88 and 2.49±0.42; GDNF group, 6.01±0.43 and 4.89±0.46). Meanwhile, the stimulation of cultured cells with GDNF increased the phosphorylation of Akt, which is a downstream effector of PI3-K/Akt. The effects of GDNF were specifically blocked by the inhibitor of the PI3-K/Akt pathway, wortmannin (Number of TH-ir cells in slice culture: PI3-K/Akt pathway-inhibited group, 6.98±0.58. Number of TH-ir cells and neurite number of TH-ir cells in cell culture: PI3-K/Akt pathway-inhibited group, 3.79±0.62 and 2.50±0.25, respectively). Conclusion: The PI3-K/Akt pathway mediates the survival/differentiation effect of GDNF on DA cells.

In recent years, the wireless mobile markets are witnessing an unprecedented growth. High-quality video service will be greatly needed as one of the hottest wireless multimedia services in the future generation wireless networks. In this paper, a novel content-based distortion control scheme is proposed to provide higher quality of the wireless video services. Our scheme adopts rate-distortion optimization techniques in state-of-the-art video coding standard H.264/AVC. In order to improve the subjective video quality in the process of encode, we create three visual distortion sensitivity models to minimize the perceptual distortion. We arrange more bits to visual distortion sensitive macroblocks during rate-distortion optimization process. The perceptual distortion in these regions is thus efficiently controlled with a relatively higher rate. Meanwhile, rate balance is achieved by allotting fewer bits to macroblocks that are perceptually less sensitive to distortion. Experiments results show that the subjective qualities of encoded video are improved without compromising PSNR.