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BACKGROUND MicroRNAs (miRNAs) have been proven to be critical players in many different types of tumors including esophageal squamous cell carcinoma (ESCC). OBJECTIVE This study aimed at investigating the correlation of miR-138 expression and clinical outcome of patients with ESCC. METHODS A total of 168 serum samples and 128 fresh cancer tissues as well as their corresponding adjacent non-cancerous tissues were collected. Real-time PCR was performed to evaluate the clinical value of miR-138 in ESCC. RESULTS Our results showed that tissue and serum miR-138 levels were both significantly reduced in ESCC compared to their respective controls. Tissue miR-138 levels were highly correlated with serum miR-138 levels. Serum miR-138 differentiated patients with ESCC from healthy controls with high accuracy. In addition, reduced tissue/serum miR-138 levels were correlated with unfavorable clinicopathological parameters including T stage, lymph node metastasis and TNM stage. ESCC patients with lower tissue/serum miR-138 levels had shorter five year overall survival compared with those with higher tissue/serum miR-138 levels. Finally, downregulation of miR-138 was demonstrated to be an independent prognostic risk factor for ESCC. CONCLUSIONS In conclusion, both tissue and serum miR-138 levels are reduced in ESCC, and might be promising prognostic biomarkers for ESCC.

An efficient parallel Stokes' solver has been developed for complete description of hydrodynamic interactions between Brownian particles in bulk and confined geometries. A Langevin description of the particle dynamics is adopted, where the long-range interactions are included using a Green's function formalism. A scalable parallel computational approach is presented, where the general geometry Stokeslet is calculated following a matrix-free algorithm using the general geometry Ewald-like method. Our approach employs a highly efficient iterative finite-element Stokes' solver for the accurate treatment of long-range hydrodynamic interactions in arbitrary confined geometries. A combination of mid-point time integration of the Brownian stochastic differential equation, the parallel Stokes' solver, and a Chebyshev polynomial approximation for the fluctuation-dissipation theorem leads to an O(N) parallel algorithm. We illustrate the new algorithm in the context of the dynamics of confined polymer solutions under equilibrium and non-equilibrium conditions. The method is then extended to treat suspended finite size particles of arbitrary shape in any geometry using an immersed boundary approach.

Double flowers in cultivated camellias are divergent in floral patterns which present a rich resource for demonstrating molecular modifications influenced by the human demands. Despite the key principle of ABCE model in whorl specification, the underlying mechanism of fine-tuning double flower formation remains largely unclear. Here a comprehensive comparative transcriptomics interrogation of gene expression among floral organs of wild type and “formal double” and “anemone double” is presented. Through a combination of transcriptome, small RNA and “degradome” sequencing, we studied the regulatory gene expression network underlying the double flower formation. We obtained the differentially expressed genes between whorls in wild and cultivated Camellia. We showed that the formation of double flowers tends to demolish gene expression canalization of key functions; the faded whorl specification mechanism was fundamental under the diverse patterns of double flowers. Furthermore, we identified conserved miRNA-targets regulations in the control of double flowers, and we found that miR172-AP2, miR156-SPLs were critical regulatory nodes contributing to the diversity of double flower forms. This work highlights the hierarchical patterning of global gene expression in floral development, and supports the roles of “faded ABC model” mechanism and miRNA-targets regulations underlying the double flower domestication.

Long non-coding RNAs (lncRNAs) have recently been demonstrated to serve crucial roles in various diseases including tumor initiation and progression. However, the role of the lncRNA MIR31HG in non-small cell lung cancer (NSCLC) was not well established. The present study demonstrated that MIR31HG was significantly increased in tumor tissues compared with adjacent normal tissues, and increased MIR31HG expression levels were associated with histological differentiation grade, lymph node metastasis and Tumor-node metastasis (TNM) stage in patients with NSCLC. Patients who had a higher MIR31HG expression level, were predicted a shorter over survival (OS) time. Using in vitro assays, the present study demonstrated that the downregulation of MIR31HG expression significantly inhibited cell proliferation and cell invasion abilities. Furthermore, it was identified that knockdown of MIR31HG expression suppressed the cell epithelial-mesenchymal transition (EMT) phenotype by reducing the expression levels of Twist1 and Vimentin, but also increased the expression level of E-cadherin in NSCLC cells. Furthermore, the results of the present study demonstrated that downregulated MIR31HG inhibited the Wnt/β-catenin signaling pathway by decreasing the expression of glycogen synthase kinase 3β (GSK3β) and β-catenin, but increasing the phosphorylated (p)-GSK3β expression in NSCLC cells. Together, these data demonstrated that MIR31HG could be identified as a poor prognostic biomarker and a novel therapeutic target for patients with NSCLC.

In this paper, a synergist complex of Ni(ii) with naphthalene-2-sulfonic acid (HNS) and n-hexyl 4-pyridinecarboxylate ester (LI), which are corresponding short chain analogues of active synergistic extractants dinonylnaphthalene sulfonic acid (HDNNS) and 2-ethylhexyl 4-pyridinecarboxylate ester (4PC, LII), was prepared and characterized by Nuclear Magnetic Resonance (1H-NMR), elemental analyses, Fourier Transform Infrared Spectroscopy (FT-IR) and Electrospray Ionization Mass Spectrometry (ESI-MS) spectroscopic studies. Single crystals of the nickel synergist complex have been grown from a methanol/water (10/1) solution and analyzed by single crystal X-ray diffraction. The crystal structure of the nickel synergist complex shows that Ni(ii) is coordinated by four water molecules and two monodentate LI ligands and there is no direct interaction of the Ni(ii) with sulfonic oxygen atoms of naphthalene-2-sulfonic acid anions, while hydrogen-bonded interactions of the coordinated water molecules with sulfonic oxygen atoms of naphthalene-2-sulphate anions were observed. In addition, in order to provide parallels to solvent extraction, the extracted Ni(ii) complex with HDNNS and 4PC is also prepared and studied using FT-IR and ESI-MS technology. Compared with their corresponding free ligand, similar shifts assigned to the stretching vibration of the pyridine ring and S[double bond, length as m-dash]O in both the nickel synergist complex and the extracted Ni(ii) complex suggest that in the non-polar organic phase, Ni(ii) is also coordinated by LII ligands, while the sulfonic oxygen atoms of dinonylnaphthalene sulfonate anions not directly bonded to Ni(ii) form hydrogen bonds with water molecules (coordinated with Ni(ii) or/and solubilized in the non-polar organic phase). For the ESI-MS spectrum of the extracted Ni(ii) complex in non-polar organic phase, there exists a peak at m/z values of 1058.76, which indicates that the extracted Ni(ii) complex in the non-polar organic phase may have a coordination structure, [Ni(H2O)4(LII)2](DNNS)2, similar to the coordination structure of the nickel synergist complex.

The system characteristics and economy of UHV power transmission differ from those of other voltage levels. This chapter first discusses the system characteristics of UHV power transmission, mainly including the parameter characteristics of the transmission lines and the main transformer, the transmission characteristics, and transmission capacity of power grid and the reliability and stability of the system as well as the characteristics of the transmission and transformation equipment, such as high-voltage shunt reactors and series capacitors. Then, the analysis on economy is made for UHV power transmission. Finally, the technical characteristics and applicable occasions of UHV power transmission will be discussed.

Ascorbate peroxidase (APX) acts indispensably in synthesizing L-ascorbate (AsA) which is pivotal to plant stress tolerance by detoxifying reactive oxygen species (ROS). Enhanced activity of APX has been shown to be a key step for genetic engineering of improving plant tolerance. However it needs a deeper understanding on the maintenance of cellular ROS homeostasis in response to stress. In this study, we identified and characterized anAPX(CaAPX) gene fromCamellia azalea. Quantitative real-time PCR (qRT-PCR) analysis showed thatCaAPXwas expressed in all tissues and peaked in immature green fruits; the expression levels were significantly upregulated upon cold and hot stresses. Transgenic plants displayed marked enhancements of tolerance under both cold and heat treatments, and plant growth was correlated withCaAPXexpression levels. Furthermore, we monitored the activities of several ROS-scavenging enzymes includingCu/Zn-SOD,CAT,DHAR, andMDHAR, and we showed that stress tolerance was synchronized with elevated activities of ROS-scavenging. Moreover, gene expression analysis of ROS-scavenging enzymes revealed a role ofCaAPXto orchestrate ROS signaling in response to temperature stresses. Overall, this study presents a comprehensive characterization of cellular response related toCaAPXexpression and provides insights to breed crops with high temperature tolerances.

The relay protection of UHVAC system consists of six parts, namely, line protection, circuit breaker protection, busbar protection, transformer protection, HV shunt reactor protection, and LV shunt reactor and LV capacitor protection. This chapter introduces basic requirements and setting principles of UHVAC protection, and analyzes the relay protection characteristics of each piece of main equipment in the UHVAC system. Then, the discussions of the protection principles configuration schemes and setting proposals for each piece of main equipment are made to provide references for designing the relay protection of UHVAC system.

Spatial On-Line Analytical Processing (SOLAP) is a powerful decision support systems tool for exploring the multidimensional perspective of spatial data. In recent years, remotely sensed data have been integrated into SOLAP cubes, and this improvement has advantages in spatio-temporal analysis for environment monitoring. However, the performance of aggregations in SOLAP still faces a considerable challenge from the large-scale dataset generated by Earth observation. From the perspective of data parallelism, a tile-based SOLAP cube model, the so-called Tile Cube, is presented in this paper. The novel model implements Roll-Up/Drill-Across operations in the SOLAP environment based on Map-Reduce, a popular data-intensive computing paradigm, and improves the throughput and scalability of raster aggregation. Therefore, the long time-series, wide-range and multi-view analysis of remotely sensed data can be processed in a short time. The Tile Cube prototype was built on Hadoop/Hbase, and drought monitoring is used as an example to illustrate the aggregations in the model. The performance testing indicated the model can be scaled along with both the data growth and node growth. It is applicable and natural to integrate the SOLAP cube with Map-Reduce. Factors that influence the performance are also discussed, and the balance of them will be considered in future works to make full use of data locality for model optimisation. Remote-sensing data aggregation in Spatial OLAP faces big data challenge.A tile-based SOLAP cube model for raster is presented based on parallel map algebra.The model integrates SOLAP with Map-Reduce for accelerating spatio-temporal aggregations.The model shows good scalability along with both increased data and node number.Complexity of the distribution is encapsulated via transparent SOLAP interface.

Glaze is composed of glassy phase, pores and a small amount of crystal phase. The glazed product is endowed high technological properties such as low water absorption, good cleanability, high bending strength and abrasion resistance, excellent chemical and soil resistance. Nevertheless, surface degradation might lead to opening of closed bubbles in glaze thus diminishing the cleanability. As a result, a study of bubble formation in glaze layer would favor the improvement of mechanical property and cleanability of final products. In this paper, glaze slurry was prepared by milling for 30 min, then applied to green bodies and dried for later use. The same glaze was fired in hot stage microscope to measure melting behavior. Two characteristic points were obtained: start of melting temperature of 1184 °C; half sphere temperature of 1220 °C. The firing curves applied to glaze can be designed according to the characteristic points, and then the dried samples were fired. The bubbles in fired glaze were observed by 3D depth of field microscope. Microhardness was performed using Vickers hardness tester. A solution was proposed to decrease bubbles and increase microhardness via changing firing process. The results showed the formation of bubbles in glaze was determined by firing process.

Glazes have great influence on most of the final properties of sanitary wares, such as color, glossy, and surface roughness. Generally, these properties have been changed by chemical composition and firing parameters. In addition, the selection of particle-size distribution of raw glaze can affect on the surface appearance and cleanability of glazed surface. In this paper, raw glazes were milled in ball mill for different time. Prepared glaze slurry was applied to green bodies, later dried and fired. The same glaze was also uniaxially pressed to form cylindrical sample; the specimen was placed on substrate surface and fired in hot stage microscope. The glaze evolution upon heating was recorded by CCD camera, the contact angle between molten glaze and substrate was measured to determine the wettability. The results showed that particle-size distributions have great influence on the melting behavior of glaze and the surface appearance of glazed ceramics.

The flavonoids metabolic pathway plays central roles in floral coloration, in which anthocyanins and flavonols are derived from common precursors, dihydroflavonols. Flavonol synthase (FLS) catalyses dihydroflavonols into flavonols, which presents a key branch of anthocyanins biosynthesis. The yellow flower of Camellia nitidissima Chi. is a unique feature within the genus Camellia, which makes it a precious resource for breeding yellow camellia varieties. In this work, we characterized the secondary metabolites of pigments during floral development of C. nitidissima and revealed that accumulation of flavonols correlates with floral coloration. We first isolated CnFLS1 and showed that it is a FLS of C. nitidissima by gene family analysis. Second, expression analysis during floral development and different floral organs indicated that the expression level of CnFLS1 was regulated by developmental cues, which was in agreement with the accumulating pattern of flavonols. Furthermore, over-expression of CnFLS1 in Nicotiana tabacum altered floral colour into white or light yellow, and metabolic analysis showed significant increasing of flavonols and reducing of anthocyanins in transgenic plants. Our work suggested CnFLS1 plays critical roles in yellow colour pigmentation and is potentially a key point of genetic engineering toward colour modification in Camellia.

Jatropha curcas L. is an excellent biofuel crop, which displays a high efficiency of carbon absorption, and seed oil of Jatropha can be efficiently processed to produce high-quality biodiesel. Plant phosphoenolpyruvate carboxylases (PEPCs) play important roles not only in initial fixation of atmospheric CO2 in C4 and Crassulacean acid metabolism (CAM) plants, but also in fatty acid biosynthesis in seeds of oil plants by regulating carbon partitioning. Here, we identified JcPEPC1 from J. curcas L. by homology cloning, and alignment analysis of protein sequence revealed JcPEPC1 was a plant C3-type PEPC, and shared high similarity to PEPC of castor oil plant Ricinus communis. We implemented detailed functional characterization of JcPEPC1 by expression analysis and transgenic tobacco. JcPEPC1 gene expressed in the leaves and seeds of J. curcas L., and remarkable increase of expression level was also detected at seed oil-accumulating stages. We overexpressed JcPEPC1 in tobacco, and showed the enzymatic activity of PEPC in transgenic plants was notably higher than wild type. Gas chromatography (GC) analysis elucidated the composition and total content of fatty acids were also altered. This study indicated JcPEPC1 played a fundamental role in fatty acid biosynthesis in Jatropha seeds. Our results proposed enhanced PEPC activity of Jatropha could improve biosynthesis of fatty acid, which implied critical functions in primary metabolism of non-photosynthetic PEPC.

Ascorbate peroxidase (APX) acts indispensably in synthesizing L-ascorbate (AsA) which is pivotal to plant stress tolerance by detoxifying reactive oxygen species (ROS). Enhanced activity of APX has been shown to be a key step for genetic engineering of improving plant tolerance. However it needs a deeper understanding on the maintenance of cellular ROS homeostasis in response to stress. In this study, we identified and characterized an APX (CaAPX) gene from Camellia azalea. Quantitative real-time PCR (qRT-PCR) analysis showed that CaAPX was expressed in all tissues and peaked in immature green fruits; the expression levels were significantly upregulated upon cold and hot stresses. Transgenic plants displayed marked enhancements of tolerance under both cold and heat treatments, and plant growth was correlated with CaAPX expression levels. Furthermore, we monitored the activities of several ROS-scavenging enzymes including Cu/Zn-SOD, CAT, DHAR, and MDHAR, and we showed that stress tolerance was synchronized with elevated activities of ROS-scavenging. Moreover, gene expression analysis of ROS-scavenging enzymes revealed a role of CaAPX to orchestrate ROS signaling in response to temperature stresses. Overall, this study presents a comprehensive characterization of cellular response related to CaAPX expression and provides insights to breed crops with high temperature tolerances.

In plants, miRNAs are endogenous small RNAs derived from single-stranded precursors with hairpin structures. The evolution of miRNAs and their targets represents one of the most dynamic circuits directing gene expression, which may play fundamental roles in shaping the development of distinct plant organs. Here we performed high-throughput small RNA sequencing in five organ types of Camellia azalea to capture the spatial profile of small non-coding RNA. In total we obtained >227 million high-quality reads and identified 175 miRNAs with mature and precursor sequences. We aligned the miRNAs to known miRNA databases and revealed some conserved as well as 'newly evolved' miRNA genes. Twelve miRNAs were identified to be specific in the genus Camellia, supporting the lineage-specific manner of expansion of 'young' miRNAs. Through differential expression analysis, we showed that many miRNAs were preferentially abundant in certain organ types. Moreover, hierarchical clustering analysis revealed distinctive expression patterns of tissue-specific miRNAs. Gene Ontology enrichment analysis of targets of stamen- and carpel-specific miRNA subclusters showed that miRNA-target regulatory circuits were involved in many important biological processes, enabling their proper specification and organogenesis, such as 'DNA integration' and 'fruit development'. Further, quantitative PCR of key miRNAs and their target genes revealed anti-correlated patterns, and uncovered the functions of key miRNA-target pairs in different floral organs. Taken together, this work yielded valuable information on miRNA-target regulation in the control of floral organ development and sheds light on the evolution of lineage-specific miRNAs in Camellia.

Surface charging or polarization can strongly affect the nature of interactions between charged dielectric objects, particularly when sharp dielectric discontinuities are involved. By relying on a generalized image method, we derive an analytical, perturbative theory of the polarization and the interactions between charged particles in many-body systems. The validity and accuracy of the theory are established by comparing its predictions to full-blown numerical solutions. The importance of polarizability is then demonstrated for clusters of dielectric spheres, as well as a periodic crystal of charged dielectric spheres arranged into a NaCl-type lattice. The analytical framework for understanding the consequences of polarization will enable molecular simulations of large systems of polarizable particles.

Large classes of materials systems in physics and engineering are governed by magnetic and electrostatic interactions. Continuum or mesoscale descriptions of such systems can be cast in terms of integral equations, whose direct computational evaluation requires O(N^2) operations, where N is the number of unknowns. Such a scaling, which arises from the many-body nature of the relevant Green's function, has precluded wide-spread adoption of integral methods for solution of large-scale scientific and engineering problems. In this work, a parallel computational approach is presented that relies on using scalable open source libraries and utilizes a kernel-independent Fast Multipole Method to evaluate the integrals in O(N) operations, with O(N) memory cost, thereby substantially improving the scalability and efficiency of computational integral methods. We demonstrate the accuracy, efficiency, and scalability of our approach in the contest of two examples. In the first, we solve a boundary value problem for a ferroelectric/ferromagnetic volume in free space. In the second, we solve an electrostatic problem involving polarizable dielectric bodies in an unbounded dielectric medium. The results from these test cases show that our parallel approach, which is built on a kernel-independent FMM, can enable highly efficient and accurate simulations and allow for considerable flexibility in a broad range of applications., Comment: 29 pages, 8 figures

The interactions of lanthanide ions (Ln3+) with bovine serum albumin (BSA) under mimetic physiological conditions (310.15 K, pH 6.7, 0.1MNaCl) were studied by microcalorimetry. For the first time, based on Two Sets of Independent Sites Model, molar enthalpies (Δr H m1, Δr H m2) and coordination number (n 1, n 2) of the two sets of binding sites with different affinity were obtained directly from the microcalorimetric results. It was shown that the interactions are endothermic and entropy-driving processes. By combining with fluorescence spectroscopy, other thermodynamic parameters (Δr G m1, Δr S m1) were determined for high-affinity specific sites.

We characterized transmission from the pedunculopotine tegmental nucleus (PPTg), which contains cholinergic and glutamatergic neurons, at synapses with noradrenergic (NAergic) A7 neurons. Injection of an anterograde neuronal tracer, biotinylated-dextran amine, into the PPTg resulted in labeling of axonal terminals making synaptic connection with NAergic A7 neurons. Consistent with this, extracellular stimulation using a train of 10 pulses at 100 Hz evoked both fast and slow excitatory synaptic currents (EPSCs) that were blocked, respectively, by DNQX, a non-N-methyl-d-aspartate receptor blocker, or atropine, a cholinergic muscarinic receptor (mAChR) blocker. Interestingly, many spontaneous-like, but stimulation-dependent, EPSCs, were seen for up to one second after the end of stimulation and were blocked by DNQX and decreased by EGTA-AM, a membrane permeable form of EGTA, showing they are glutamatergic EPSCs causing by asynchronous release of vesicular quanta. Moreover, application of atropine or carbachol, an mAChR agonist, caused, respectively, an increase in the number of asynchronous EPSCs or a decrease in the frequency of miniature EPSCs, showing that mAChRs mediated presynaptic inhibition of glutamatergic transmission of the PPTg onto NAergic A7 neurons. In conclusion, our data show direct synaptic transmission of PPTg afferents onto pontine NAergic neurons that involves cooperation of cholinergic and glutamatergic transmission. This dual-transmitter transmission drives the firing rate of NAergic neurons, which may correlate with axonal and somatic/dendritic release of NA.

Soluble leptin receptor (sLepR) is the main leptin-binding protein in plasma and contributes to activation of circulating leptin. In this study, we identified a sLepR in plasma of crucian carp (Carassius carassius) using a pull-down assay, and the interaction of sLepR with its ligand is confirmed by a cross-linking study. In addition, we found that leptin-a has higher affinity than leptin-b for sLepR. According to our knowledge, this is the first experimental report about the main ligand of sLepR in teleost.

The transition from vegetative to reproductive growth in woody perennials involves pathways controlling flowering timing, bud dormancy and outgrowth in responses to seasonal cues. However little is known about the mechanism governing the adaptation of signaling pathways to environmental conditions in trees. Camellia azalea is a rare species in this genus flowering during summer, which provides a unique resource for floral timing breeding. Here we reported a comprehensive transcriptomics study to capture the global gene profiles during floral bud development in C. azalea. We examined the genome-wide gene expression between three developmental stages including floral bud initiation, floral organ differentiation and bud outgrowth and identified nine co-expression clusters with distinctive patterns. Further, we identified the differential expressed genes (DEGs) during development and characterized the functional properties of DEGs by Gene Ontology analysis. We showed that transition from floral bud initiation to floral organ differentiation required changes of genes in flowering timing regulation, while transition to floral bud outgrowth was regulated by various pathways such as cold and light signaling, phytohormone pathways and plant metabolisms. Further analyses of dormancy associated MADS-box genes revealed that SVP- and AGL24- like genes displayed distinct expression patterns suggesting divergent roles during floral bud development.

Plasma jet can generate a remote non-equilibrium plasma out of its intra-electrode region, which has application potentials in a large variety of fields. Now, it has become a key issue in low-temperature plasma research. It is important to decrease the gas temperature of the plasma plume for industrial applications, especially for biomedical application. In this paper, with ambient air used as working gas, an atmospheric pressure plasma jet in a needle-to-ring electrode geometry is developed to generate a non-thermal plasma plume excited by a direct current voltage, which has a so low temperature that can be touched directly by human body. Through electrical and optical methods, it is found that the discharge can operate in two distinct modes: a pulsed mode or a continuous mode. For the pulsed mode, the discharge frequency increases with increasing the gas flow rate or the power output voltage. For the continuous mode, the voltage-ampere characteristics are investigated for different gas flow rates, which indicate that the discharge is in an abnormal glow regime. Moreover, the gas temperature of the plasma plume is investigated through an optical fiber thermometer. It is found that the gas temperature of the plasma plume increases with increasing the power voltage or decreasing the gas flow rate. Compared with the continuous mode, the pulse mode has a lower gas temperature, so that its plume can be touched directly by a human finger. Therefore, the plasma jet in the pulsed mode is more important for the application in biomedical field. The optical emission spectrum from the two discharge modes is detected to calculate the molecular vibrational temperature. Result indicates that the vibrational temperature as a function of the experimental parameters is similar to the variance of the gas temperature. The physical phenomena mentioned above are discussed and qualitative explanations are given. These results are important for the further investigation of discharge mode and application of direct-current voltage excited plasma jet.

In Rhodobacter sphaeroides, transfer of the first electron in quinol oxidation by the bc(1) complex shows kinetic features (a slow rate (approx. 1.5 x 10(3)/s), high activation energy (approx. 65 kJ/mol) and reorganization energy, lambda (2.5 V)) that are unexpected from Marcus theory and the distances shown by the structures. Reduction of the oxidized iron-sulfur protein occurs after formation of the enzyme-substrate complex, and involves a H-transfer in which the electron transfer occurs through the approx. 7 A of a bridging histidine forming a H-bond with quinol and a ligand to 2Fe-2S. The anomalous kinetic features can be explained by a mechanism in which the electron transfer is constrained by coupled transfer of the proton. We discuss this in the context of mutant strains with modified E(m,7) and pK for the iron-sulfur protein, and Marcus theory for proton-coupled electron transfer. We suggest that transfer of the second proton and electron involve movement of semiquinone in the Q(o) site, and rotation of the Glu of the conserved -PEWY- sequence. Mutational studies show a key role for the domain proximal to heme b(L). The effects of mutation at Tyr-302 (Tyr-279 in bovine sequence) point to a possible linkage between conformational changes in the proximal domain, and changes leading to closure of the iron-sulfur protein access channel at the distal domain.

Ammopiptanthus mongolicus shows very strong resistance to severe environments. To isolate drought-resistant genes and elucidate drought-resistant molecular mechanisms of the plant, we constructed a drought-induced full-length cDNA library using SMART (Switching mechanism at 5'-end of RNA transcript) technique. The phage titer of the unamplified library was 1.6 x 10(7) PFU/mL; the recombination percentage was 97.7%; and the sizes of most cloned cDNA fragments were around 1 kb. Three thousand positive clones were randomly selected and sequenced from their 5' ends, and a total of 1 450 Unigenes were identified. By Blast searches against the Nt, Nr and Swissprot databases, we found that 919 Unigenes (amount to 63.4%) showed significant similarity to the annotated genes, and the remaining 531 Unigenes (amount to 36.6%) represented novel genes without any annotation. Among the functional categories of the GO (Gene Ontology) classification, the terms related to physiological process, cellular process, binding, catalytic activity and cellular components were dominant. The next abundant terms were for organelle, protein complex, transporter activity and structural molecule activity. In addition, there were a significant proportion of the terms involved in stimulus response, gene expression regulation, regulation of physiological and biochemical processes and signal transduction. Many of the annotated Unigenes were found to be related to plant resistance to abiotic stresses, and expression analyses of 6 out of these genes by semi-quantitive RT-PCR confirmed their involvements in the response of A. mongolicus to drought stress. These results laid a foundation for the expression profile analysis and the cloning and characterization of drought-resistant genes from the plant in the future.

How environmental cues regulate adult stem cell and cancer cell activity through surface receptors is poorly understood. Angiopoietin-like proteins (ANGPTLs), a family of seven secreted glycoproteins, are known to support the activity of haematopoietic stem cells (HSCs) in vitro and in vivo. ANGPTLs also have important roles in lipid metabolism, angiogenesis and inflammation, but were considered 'orphan ligands' because no receptors were identified. Here we show that the immune-inhibitory receptor human leukocyte immunoglobulin-like receptor B2 (LILRB2) and its mouse orthologue paired immunoglobulin-like receptor (PIRB) are receptors for several ANGPTLs. LILRB2 and PIRB are expressed on human and mouse HSCs, respectively, and the binding of ANGPTLs to these receptors supported ex vivo expansion of HSCs. In mouse transplantation acute myeloid leukaemia models, a deficiency in intracellular signalling of PIRB resulted in increased differentiation of leukaemia cells, revealing that PIRB supports leukaemia development. Our study indicates an unexpected functional significance of classical immune-inhibitory receptors in maintenance of stemness of normal adult stem cells and in support of cancer development.

China Train Control System level 3 (CTCS-3) transmits bi-directional track-train data via Global System Mobile for Railway (GSM-R) network, and GSM-R network should provide secure wireless environment to ensure train operation safety. GSM-R network handoff will cause a brief interruption of communication. If a train control message is on transmission during this interruption time, some message data units may be erroneously transmitted during the transmission interference and must be corrected by re-transmission. These re-transmissions result in a delay. This paper analysis's the message transfer mechanism, summarizes some factors influence on the message of Movement Authority (MA) transfer delay during a handoff interference, obtains values of transfer delay of MA affected by handoff, and at last verifies that recovery period of GSM-R network required in QoS specification can meet the needs of train control data transmission.

MODIS (Moderate Resolution Imaging Spectroradiometer, Moderate Resolution Imaging Spectroradiometer) is carrying on a major satellite remote sensing sensors of EOS series in the United States. MODIS remote sensing data is the new generation of satellite remote sensing information sources; it has broad application prospects in ecological research, environmental monitoring, global climate change and agricultural resources survey and other studies. MODIS data has featured a large volume of data and dealing with complex. In this paper Grid Computing technology brought to the processing of MODIS L1B Data is in order to improve the efficiency. First of all, this paper gives a brief introduction of MODIS L1B data and its application status, also talks about gird computing. Then the structure of MODIS L1B Data Process Based on Grid Computing (MLDPGRID) on logic is given, also explain the function of three tiers. In the realization section, receiving of MODIS L1B data, Grid Platform, software environment and network architecture, processing of MODIS L1B data and portal of MLDPGRID are all discussed. Finally, the paper gives the evaluation and conclusion of the MLDPGRID, meanwhile the optimization strategy and future work are discussed.

Moderate resolution imaging spectror adiometer (MODIS) remote sensing data is one of the new generation satellite remote sensing information sources. Composition of MODIS data is involved in a large number of complex calculations. In this paper, we present a plan of automatic composition of MODIS data based on grid. First of all, the framework is given which is designed for automatic composite of MODIS data based on grid. It achieves the high efficiency of automatic process through task division, task scheduling, distribute strategies and data communication mode. On the basis of business characteristics of MODIS composition, we divide the tasks and rebuild sub-tasks properly, then take different scheduling and distribute strategies to the grid tasks according to different flows and jobs. Meanwhile, we compare three communication modes, and then realize it in the efficient way. Finally, the paper gives evaluation of the grid and looks forward to the future work.

With the rapid development of Internet / Intranet and computer technology, geographic information system (GIS) has gone through the development process from a single application environment to the network application environment, web GIS has gradually become a mainstream application of GIS. Compared with the Client / Server structure, web GIS has the characteristics of deployment with convenient, simple to use, the low requirement of network bandwidth. This paper introduces web GIS and extensible markup language (XML), explains their research status and advantages. Then we focus on how to design a web GIS framework based on XML with the characteristics of universality and flexibility. First, we give the web GIS framework, and then explain the function of each component of web GIS framework. Meanwhile, we discuss the implementation of the web GIS framework through two application systems. Finally, we look forward to the future work.

A stable plasma plume in brush shape is generated with fairly large area in the ambient air at atmospheric pressure through using argon as the working gas and a direct-current (DC) excited line-plate discharge device. The discharge characteristics of the brush-shaped plume are investigated by optical method. Results show that both the light emission and the current signal are periodically pulsed despite that the discharge is excited by the DC power supply. The light emission frequency is investigated through a photomultiplier tube, and it is found that the discharge frequency increases with increasing the applied voltage or the gas flow rate. Spatially resolved measurements are conducted for the light emission from the plasma plume along the ground electrode and the gas flow, respectively. Results indicate that the uniform plume is composed of micro-discharges, which appear stochastically in time along the line electrode. Along the gas flow direction, the microdischarge propagates in the method of plasma bullets in a high velocity. The optical emission spectrum from the plume is detected by a spectrometer, and the molecular vibrational temperature is calculated based on the discharge spectrum. It is found that the molecular vibrational temperature increases with increasing the voltage or decreasing the gas flow rate.