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Objective: The study aimed to investigate the relationship between the corpus callosum area (CCa) and the degree of cerebral atrophy in patients with cerebral atrophy. Methods: 119 patients with brain atrophy were grouped according to the degree of brain atrophy. Median sagittal CCa and intracranial area (ICa) were measured, and the ratio of corpus callosum to the intracranial area (CCa-ICa ratio) was calculated. The data were analyzed using ANOVA. Results: CCa significantly reduced in patients with cerebral atrophy, and the degree of cerebral atrophy was found to be positively correlated with the degree of reduction in the CCa. Conclusion: The reduction in the CCa and the CCa-ICa ratio in the median sagittal can be used as a reference indicator for the diagnosis and grading of brain atrophy in clinical practice.

Geomorphometry, the science of digital terrain analysis (DTA), is an important focus of research in both geomorphology and geographical information science (GIS). Given that 70% of China is mountainous, geomorphological research is popular among Chinese scholars, and the development of GIS over the last 30 years has led to significant advances in geomorphometric research. In this paper, we review Chinese progress in geomorphometry based on the published literature. There are three major areas of progress: digital terrain modelling methods, DTA methods, and applications of digital terrain models (DTMs). First, traditional vector- and raster-based terrain modelling methods, including the assessment of uncertainty, have received widespread attention. New terrain modelling methods such as unified raster and vector, high-fidelity, and real-time dynamic geographical scene modelling have also attracted research attention and are now a major focus of digital terrain modelling research. Second, in addition to the popular DTA methods based on topographical derivatives, geomorphological features, and hydrological factors extracted from DTMs, DTA methods have been extended to include analyses of the structure of underlying strata, ocean surface features and even socioeconomic spatial structures. Third, DTMs have been applied to fields including global climate change, analysis of various typical regions, lunar surface and other related fields. Clearly, Chinese scholars have made significant progress in geomorphometry. Chinese scholars have had the greatest international impact in areas including high-fidelity digital terrain modelling and DTM-based regional geomorphological analysis, particularly in the Loess Plateau and the Tibetan Plateau regions.

We presented a rare case with giant ureteral polyp that mimics bladder tumor in adult women, originating from the middle segment of the left ureter. The patient was a 42-year-old woman, with a 2.1×1.3 cm bladder mass detected incidentally on a health screening ultrasound. Computerized tomography (CT) of the pelvis revealed a solid tumor situated near to trigon. Cystoscopy demonstrated a tumor that periodically prolapsed into the bladder. After the tumor was identified as a ureteral polyp by ureteroscopy, an ureteroscopic resection by diode laser was performed. The tumor measured 9.0×0.5 cm, and the final pathological diagnosis was ureteral fibroepithelial polyp. No recurrence was observed at the 5-month follow-up.

Neuronal apoptosis is one of the prominent features involved in spinal cord injury (SCI). MicroRNAs (miRNAs) are small non-coding RNAs that functions in a variety of cellular processes including apoptosis. MiRNAs have been implicated as effectors of SCI. However, role of miRNAs in SCI-associated neuronal apoptosis remains to be investigated. A number of bioinformatics approaches have suggested Mcl-1 and BH3-only family genes as potential downstream targets regulated by miR-20a and miR-29b, respectively. To determine whether miR-20a and miR-29b play a role in neuronal apoptosis of SCI by regulating those genes, we transfected Neuro-2A neuroblastoma cells with mimic and inhibitor for the two miRNAs. The miR-20a mimic decreased Mcl-1 expression and the miR-29b mimic reduced the expression of Bad, Bim, Noxa and Puma. The repressor role of miR-20a and miR-29b is confirmed by the transfection of Neuro-2A cells with their inhibitor. Moreover, miR-20a mimic or miR-29b inhibitor attenuated Neuro-2A cell viability and co-transfection of both further diminished the viability of these cells. The in vitro effects of miR-20a and miR-29b on neuronal apoptosis were corroborated by the in vivo studies. Injection of miR-20a mimic or miR-29b inhibitor into the lesion of the injured spinal cord rescued the neuronal death and co-injection of both completely abolished SCI-induced apoptosis. In conclusion, altered expression of miR-20a and miR-29b may cooperatively contribute to the neuronal cell death of SCI through down-regulating anti-apoptotic myeloid cell leukemia sequence-1 (Mcl-1) and up-regulating pro-apoptotic BH3-only proteins.

Concentrations of dissolved and particulate organic carbon (DOC and POC) were documented in 1996–1997 at 4 different trophic state stations in Donghu Lake, a typical shallow eutrophic lake along the Changjiang River's middle reaches. The mean concentrations of DOC were 15.11±3.26, 15.19±4.24, 14.27±3.43, and 13.31±3.30 mg/L in Station I, II, III, and IV, respectively. The DOC concentrations of the studied area were very similar to that in other lakes along the Changjiang River's middle reaches. The POC mean of the whole lake was 5.01 mg/L due to the large amount of organic detritus of both allochthonous and autochthonous origin. Significant linear relationship was found between POC and chlorophyll a at all 4 stations, which presumably reflect that phytoplankton, its exudates and its metabolic products were the main contributors to the POC pool in the water column. The slope of such linear relationship at Station IV was significantly steeper than that at Station I, II and III. In addition, the DOC/POC ratios (mean value: 4.40) indicated that the organic detritus was the most important component of the particulate organic matter; in other works, next to organic detritus, phytoplankton dominated the particulate organic matter in Donghu Lake.

TheMicrocystis bloom that once disappeared from Donghu Lake, a shallow, eutrophic Chinese lake, was successfully resumed with the use of the enclosure method. Seston and dissolved organic carbon (DOC) dynamics during theMicrocystis bloom were investigated with particular emphasis on the effect of three Chinese domestic fishes (silver carp, bighead carp and grass carp). The results showed that the change of chlorophyll a obviously related to the fish species and its stocking density. Due to the release of extracellular ogranic carbon and increased bacterial activity, DOC increased apparently after silver and bighead carps were introduced. POC/DOC dropped considerably in the enclosures containing silver and bighead carps and in the surrounding lake water, which implied that the bacterial activity was more pronounced in such ecosystems. Statistical analysis indicated that the linear relationship between POC and chlorophyll a could reflect the state of algal growth and nutrient metabolism. It was expected that this study would provide some information on biomanipulation in the shallow, eutrophic lakes.

We have studied the light induced rapid thermal diffusion of boron atom in silicon. The samples were heated by the rapid thermal processor. We have carried out spreading resistance and deep level transient spectroscopy (DLTS) measurements. The impurity distribution profile is much shallower and steeper than that of conventional thermal diffusion and the diffusion depth can be controlled to 0.1 μm. Several peaks in the deep level transient spectra were detected and the density of these defects ranges from 0.5×1012 to 5.6×1012 /cm3. The passivation and annihilation of these defects have been studied. We have also made the planar diode whose diameter is 500 μm. The reverse current and the back breakdown voltage of the planar diode are 10-9 A and 80 V respectively.

In the electricity market, the initial problem considered by the power companies is the security and economics of power system. Before the electrical transaction, the power companies not only consider the power plants' competitive bidding spot price and volume, but also pay attention to the original purchase contract with the original power plants and the spinning reserve of power system. Therefore, it is necessary to coordinate the volumes among the contract bid, the competitive bids and the spinning reserve for the predicted generation volumes. Only in this way could protect the benefit of power plants, maximize the profit of power companies, make the power market steadily and power system securely, and carry out the purpose of power system restructuring and deregulation. Aiming at this, the paper puts forward a new model for the economically apportioning strategies among the competitive bids, the purchase contracts and the spinning reserve volumes. At the same time, a simplified model is taken for the seeking process. Linear programming and approach based on phase-out were used to solve the model, and the process became simple and credible. The analysis of case based on Matlab6.1 proves this approach is simpler and more reasonable

The static shortest path problem has been solved well. However, in reality, more networks are dynamic and stochastic. The states and costs of network arcs and nodes are not only uncertain but also correlated with each other, and the costs of the arcs and nodes are subject to a certain probability distribution. Therefore, it is more general to model the shortest path problem as a dynamic and stochastic optimization problem. In this paper, the dynamic and stochastic characteristics of network nodes and arcs and the correlation between the nodes and arcs are analyzed. The dynamic stochastic shortest path is determined. The dynamic stochastic optimization model of shortest path is provided, and a shortest path genetic algorithm is proposed to solve dynamic and stochastic shortest path problem. The effective and reasonable genetic operators are designed according to the topological characteristics of the network. The experimental results show that this algorithm can be used to effectively solve the dynamic stochastic shortest path problem. The proposed model and algorithm can be applied to the network flow optimization problem in transportation, communication networks, etc.

This paper introduces a joint nonlinearity and chromatic dispersion pre-compensation method for coherent optical orthogonal frequency-division multiplexing systems. The research results show that this method can reduce the walk-off effect and can therefore equalize the nonlinear impairments effectively. Compared with the only other existing nonlinearity pre-compensation method, the joint nonlinearity and chromatic dispersion pre-compensation method is not only suitable for low-dispersion optical orthogonal frequency-division multiplexing system, but also effective for high-dispersion optical orthogonal frequency-division multiplexing transmission system with higher input power but without optical dispersion compensation. The suggested solution does not increase computation complexity compared with only nonlinearity pre-compensation method. For 40 Gbit/s coherent optical orthogonal frequency-division multiplexing 20×80 km standard single-mode fibre system, the suggested method can improve the nonlinear threshold (for Q > 10 dB) about 2.7, 1.2 and 1.0 dB, and the maximum Q factor about 1.2, 0.4 and 0.3 dB, for 2, 8 and 16 ps/(nm·km) dispersion coefficients.

Fiber nonlinearity impairments in a 40-Gb/s coherent optical orthogonal frequency division multiplexing (COOFDM) system are post-compensated for by a new method of fiber nonlinearity post-compensation (FNPC). The FNPC located before the CO-OFDM receiver includes an optical phase conjugation (OPC) unit and a subsequent 80-km-high nonlinear fiber (HNLF) as a fiber nonlinearity compensator. The OPC unit is based on a four wave mixing effect in a semiconductor optical amplifier. The fiber nonlinearity impairments in the transmission link are post-compensated for after OPC by transmission through the HNLF with a large nonlinearity coefficient. Simulation results show that the nonlinear threshold (NLT) (for Q > 10 dB) can be increased by about 2.5 dB and the maximum Q factor is increased by about 1.2 dB for the single-channel 40-Gb/s CO-OFDM system with periodic dispersion maps. In the 50-GHz channel spacing wavelength-division-multiplexing system, the NLT increases by 1.1 dB, equating to a 0.7 dB improvement for the maximum Q factor.

When developing aero-engines, problems with respect to reliability maybe come because of designs, but the manufacture process causes a lot. The purpose to study the process reliability is to cut down and eliminate the process defects/failures, which will improve the pass rate. This paper puts forward the concept, evaluations, and the contents of process reliability, and method to analyze process reliability. In addition, a case will be used to certificate this analysis.