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Abstract In order to construct virtual land environment for virtual test, we propose a construction method of virtual land environment using multi-satellite remote sensing data, the key step of which is accurate recognition of ground object. In this paper, a method of ground object recognition based on hyperspectral image (HSI) was proposed, i.e., a HSI classification method based on information measure and convolutional neural networks (CNN) combined with spatial-spectral information. Firstly, the most important three spectra of the hyperspectral image was selected based on information measure. Specifically, the entropy and color-matching functions were applied to determine the candidate spectra sets from all the spectra of the hyperspectral image. Then three spectra with the largest amount of information were selected through the minimum mutual information. Through the above two steps, the dimensionality reduction for hyperspectral images was effectively achieved. Based on the three selected spectra, the CNN network input combined with the spatial-spectral information was designed. Two input strategies were designed: (1) The patch surrounding the pixel to be classified was directly intercepted from the grayscale images of the three selected spectra. (2) In order to highlight the effect of the spectrum of the pixel to be classified, all the spectral components of this pixel were superimposed on the patch obtained by the previous strategy. As a result, a new patch with more prominent spectral components of the pixel to be classified was obtained. Using the two public hyperspectral datasets, Salinas and Pavia Center, the experiments of on both parameter selection and classification performance were performed to verify that the proposed methods had better classification performance.

The nuclear data processing code NECP-Atlas, developed at Xi’an Jiaotong University, has various functions to process the evaluated nuclear data to generate the applied nuclear data library for the nuclear reactor designs. In this paper, the photonrelated data generation capacities were developed in NECPAtlas, including the photon production cross sections and photon irradiation cross sections. In the conventional nuclear data processing code such as NJOY, only the production cross section for the prompt photon released with the neutroninduced reactions, and the photonatom reaction cross section can be produced, while the delayed photon released by the fission products is ignored regardless of its large contribution for the heating of the regions without fissionable materials such as control and reflector assemblies in fast neuron reactors. In this paper, the capacity for the generation of the production cross section for the delayed photon was developed in NECPAtlas. Besides, in the conventional nuclear data processing code, only the neutron irradiation damage cross section can be generated, while in the practical reactors, electron and positron also cause significant irradiation damage. The photonatom reactions, including Compton scattering, pair production and photoelectric effect, emit electron and positron. Therefore, the photon can also cause irradiation damage. To satisfy the demands from various application aspects, the capacity for the calculation of the photon irradiation damage cross sections was also developed in NECPAtlas. Meanwhile, the electron and positron irradiation damage cross section can also be produced, because it is the basis for the calculation of photon irradiation damage cross section. The delayed photon production cross sections were tested on the EBRⅡ fast reactor, and the results were compared with the library of the ERANOS which includes the production cross section of delayed photon. The difference of photon heating calculated based on the two libraries respectively from NECPAtlas and ERANOS is less than 0.93%, which means the correctness of the delayed photon data produced by NECPAtlas. Besides, the numerical results show that if the delayed photon is ignored, the difference of photon heating for the control assembly and reflector assembly can reach 3258% and 2041%, compared with the results of considering the delayed photon. The electron and positron displacement damage cross sections of Fe and Au calculated by NECPAtlas were verified with the results published by Oka Ridge National Laboratory, and the photon displacement cross sections calculated by NECPAtlas were verified with results reported by other researches. The numerical results show good agreement with the reference results.

This paper mainly contributes to the estimation of 2-D current-density distribution in a moving arc root. For this purpose, the multiple-split-cathode-with-different-slit-angle method is used to perform measurements of the linear current distribution of the arc root in seven different directions. On the basis of the measurement results, a large system of linear algebraic equations is treated with the algebraic-reconstruction-technique algorithm to obtain the 2-D current density. The calculation results indicate that the transverse profile of current density in a moving arc root can be characterized by a high-current core with two low-current hysteretic wings and that the maximum current density tends to the fore part of it. Index Terms--Algebraic-reconstruction-technique (ART) algorithm, arc root, current-density distribution, split-electrode method.

The influence of electrode erosion on the arc behavior during opening process of low-voltage circuit breakers is analyzed. The results have shown that the immobility time of both moving contact and stationary contact is longer considering electrodes erosion.

The article describes the subcellular allocation of N-methyl-D-aspartic acid receptor subunit 1 in neural stem cells located at the subventricular portion of adult rats. The study was conducted through electron microscopy, immunohistochemistry, and immunogold-silver double staining. Results of the study showed that neural stem cells exist in the subventricular zone, where the receptor is allocated in the membrane, cytoplasm, and Golgi complex of the stem cells.

This paper focuses on the numerical research of the influence of polymer (polyoxymethylene) on the arc behavior during arc-motion process. The mathematical model of 3-D air-arc plasma considering the ablation of sidewalls is built based on magnetic hydrodynamics. The mass-fraction equation is introduced to the model on the basis of traditional mass, momentum, and energy-balance equations. The influence of wall ablation on the thermodynamic and transport properties of air-polymer mixtures is considered in this paper. The distributions of temperature field, pressure field, and mass fraction in the arc chamber are calculated. The simulation results indicate that the vapor concentration behind the arc column is higher than that in front of the arc column because of the existence of "vortex" in the arc chamber. The use of polymers could accelerate arc movement and reduce the probability of occurrence of back-striking. Using polymers can also increase arc voltage, which can be explained by the change of electrical conductivity for air-polymer vapor mixtures. [ABSTRACT FROM AUTHOR]

The immediate early gene, activity-regulated cytoskeleton-associated protein (Arc), has been implicated in synaptic plasticity. However, the role of Arc in alcoholism is unknown. Here, we report that the anxiolytic effects of acute ethanol were associated with increased brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (trkB) expression, increased phosphorylation of extracellular signal-regulated kinases 1/2 (Erk1/2), Elk-1, and cAMP responsive element-binding protein (CREB), increased Arc expression, and increased dendritic spine density (DSD) in both the central amygdala (CeA) and medial amygdala (MeA) but not in the basolateral amygdala (BLA) of rats. Conversely, the anxiogenic effects of withdrawal after long-term ethanol exposure were associated with decreased BDNF and trkB expression, decreased phosphorylation of Erk1/2, Elk-1, and CREB, decreased Arc expression, and decreased DSD in both the CeA and MeA but not in the BLA of rats. We also showed that BDNF infusion into the CeA normalized phosphorylation of Erk1/2, Elk-1, and CREB, and normalized Arc expression, thereby protecting against the onset of ethanol withdrawal-related anxiety. We further demonstrated that arresting Arc expression in the CeA decreased DSD, thereby increasing anxiety-like and alcohol-drinking behaviors in control rats. These results revealed that BDNF-Arc signaling and the associated DSD in the CeA, and possibly in the MeA, may be involved in the molecular processes of alcohol dependence and comorbidity of anxiety and alcohol-drinking behaviors. [ABSTRACT FROM AUTHOR]

The cAMP response element-binding protein (CREB) gene transcription factor has been shown to play a role in the synaptic plasticity associated with drug addictive behaviors; however, the causal role of the CREB gene in alcohol-drinking behaviors is unknown. The present investigation evaluated alcohol-drinking behaviors in mice that are haplodeficient in CREB as a result of targeted CREB (α and Δ) gene disruption. It was found that CREB-haplodeficient (+/-) mice have higher preference for ethanol but not for sucrose solution than wild-type (+/+) littermates. The functional aspects of the CREB gene transcription factor were also investigated by measuring the protein levels of phosphorylated CREB (p-CREB) and the expression of cAMP- inducible genes such as neuropeptide Y (NPY) and brain-derived neurotrophic factor (BDNF). Deletion of the CREB (α and Δ) gene significantly decreases total CREB, p-CREB levels and the expression of NPY and BDNF in the brain structures of CREB-deficient (+/-) mice. It was also found that CREB-deficient (+/-) mice displayed more anxiety-like behaviors and that acute ethanol exposure produced anxiolytic effects and significantly increased protein levels of p-CREB and NPY in the central and medial but not in the basolateral amygdala of wild-type mice, but these effects are attenuated in CREB-deficient mice compared with wild-type mice. These results provide the first direct evidence that a haplodeficiency of the CREB gene is associated with increased alcohol-drinking behaviors. Furthermore, alcohol drinking and anxiety-like behaviors in CREB-haplodeficient mice may possibly be related to decreased expression of NPY and BDNF in the brains of these mice. [ABSTRACT FROM AUTHOR]

The stromal cell-derived factor 1/C-X-C chemokine receptor type 4 (SDF-1/CXCR-4) axis plays an important role during stem cell recruitment. SDF-1 can also bind the more recently described CXCR-7 receptor, but effects of SDF-1/CXCR-7 signaling on stem cell migrating to ischemic brain injury area are little known. In the present study, we investigated the effect of CXCR-7 on bone marrow mesenchymal stem cell (BMSC) migration toward SDF-1a in the cerebral ischemia/reperfusion (I/R) rat hippocampus. We cultured BMSCs from rats and characterized them using flow cytometry, immunocytochemistry, western blotting, and immunofluorescence to detect SDF-1a, CXCR-4, and CXCR-7 expression in third passage BMSCs (P3-BMSCs). We also prepared the model of transient cerebral I/R by four-vessel occlusion (4-VO), and BMSCs were transplanted into I/R rat brain via lateral ventricle (LV) injection (20 µl, 1 x 106/ml). After that, we examined the effect of BMSCs migration in the cerebral I/R rat hippocampus through Transwell chamber assay. Our results show that SDF-1a, CXCR-4, and CXCR-7 were expressed in P3-BMSCs. Moreover, SDF-1a expression was increased in I/R hippocampus. At 48 h after transplant, green fluorescent BrdU-BMSCs were observed in transplant groups, but no green fluorescent BrdU-BMSCs were seen in medium group. Among BMSCs transplant groups, the number of BrdU-BMSCs positive cell was the highest in BMSC group. Treatment with AMD3100 and/or CXCR-7 neutralizing antibody decreased the number of BMSC migration. Collectively, these findings indicate that CXCR-4 and -7 receptors were co-expressed in BMSCs and synergistically promoted BMSC migration. The effect of CXCR-7 was stronger than that of CXCR-4. Moreover, BMSCs that migrated to hippocampus promoted the autocrine and paracrine signaling of SDF-1a. [ABSTRACT FROM AUTHOR]

The common inhalation anesthetic isoflurane has been shown to induce apoptosis, which then leads to accumulation of β-amyloid protein, the hallmark feature of Alzheimer disease neuropathogenesis. The underlying molecular mechanism of the isoflurane-induced apoptosis is largely unknown. We, therefore, set out to assess whether isoflurane can induce apoptosis by regulating Bcl-2 family proteins, enhancing reactive oxygen species (ROS) accumulation, and activating the mitochondrial pathway of apoptosis. We performed these studies in cultured cells, primary neurons, and mice. Here we show for the first time that treatment with 2% isoflurane for 6 h can increase pro-apoptotic factor Bax levels, decrease anti-apoptotic factor Bcl-2 levels, increase ROS accumulation, facilitate cytochrome c release from the mitochondria to the cytosol, induce activation of caspase-9 and caspase-3, and finally cause apoptosis as compared with the control condition. We have further found that isoflurane can increase the mRNA levels of Bax and reduce the mRNA levels of Bcl-2. The isoflurane-induced ROS accumulation can be attenuated by the intracellular calcium chelator BAPTA. Finally, the anesthetic desfiurane does not induce activation of mitochondrial pathway of apoptosis. These results suggest that isoflurane may induce apoptosis through Bcl-2 family proteins- and ROS-associated mitochondrial pathway of apoptosis. These findings, which have identified at least partially the molecular mechanism by which isoflurane induces apoptosis, will promote more studies aimed at studying the potential neurotoxic effects of anesthetics. [ABSTRACT FROM AUTHOR]

We investigated the role of cAMP-responsive element-binding protein (CREB) in genetic predisposition to anxiety and alcohol-drinking behaviors using alcohol-preferring (P) and -nonpreferring (NP) rats. The levels of CREB, phosphorylated CREB, and neuropeptide Y (NPY) were innately lower in the central amygdala (CeA) and medial amygdala (MeA), but not in the basolateral amygdala (BLA), of P rats compared with NP rats. P rats displayed higher baseline anxiety-like behaviors and consumed higher amounts of alcohol compared with NP rats. Ethanol injection or voluntary intake reduced the higher anxiety levels in P rats. Ethanol also increased CREB function in the CeA and MeA, but not in the BLA, of P rats. Infusion of the PKA activator Sp-cAMP or NPY into the CeA decreased the alcohol intake and anxiety-like behaviors of P rats. PKA activator infusion also increased CREB function in the CeA of P rats. On the other hand, ethanol injection or voluntary intake did not produce any changes either in anxiety levels or on CREB function in the amygdaloid structures of NP rats. Interestingly, infusion of the PKA inhibitor Rp-cAMP into the CeA provoked anxiety-like behaviors and increased alcohol intake in NP rats. PKA inhibitor decreased CREB function in the CeA of NP rats. These novel results provide the first evidence to our knowledge that decreased CREB function in the CeA may be operative in maintaining the high anxiety and excessive alcohol-drinking behaviors of P rats. [ABSTRACT FROM AUTHOR]