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SUMMARY The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase that is involved in regulating cell-cycle progression. It has been widely studied in yeast and animal cells, but the function and regulation of the APC/C in plant cells are largely unknown. The Arabidopsis APC/C comprises at least 11 subunits, only a few of which have been studied in detail. APC4 is proposed to be a connector in the APC/C in yeast and animals. Here, we report the functional characterization of the Arabidopsis APC4 protein. We examined three heterozygous plant lines carrying apc4 alleles. These plants showed pleiotropic developmental defects in reproductive processes, including abnormal nuclear behavior in the developing embryo sac and aberrant cell division in embryos; these phenotypes differ from those reported for mutants of other subunits. Some ovules and embryos of apc4/+ plants also accumulated cyclin B protein, a known substrate of APC/C, suggesting a compromised function of APC/C. Arabidopsis APC4 was expressed in meristematic cells of seedlings, ovules in pistils and embryos in siliques, and was mainly localized in the nucleus. Additionally, the distribution of auxin was distorted in some embryos of apc4/+ plants. Our results indicate that Arabidopsis APC4 plays critical roles in female gametogenesis and embryogenesis, possibly as a connector in APC/C, and that regulation of auxin distribution may be involved in these processes.

With the rapid development of rural socio-economic in China, multi-source statistical information is one kind important data to enhance decision-making for government. The rural has become a major problem. In this paper, a set of GIS spatial analysis methods of rural social-economic data were proposed and researched on, spatial data and statistical data were integrated to create a comprehensive spatial database to realize data sharing with existent e-government system. On this basis, a GIS based rural socio-economic statistical system is constructed using COM pattern and put into effect in National Bureau of Statistics of China. It is proved that GIS technology applied in rural statistics department, which provides an information platform that manage and analyze statistical data and spatial data, is feasible and efficient.

A new method based kernel principal component analysis (KPCA) is used to extract interesting misalignment features from a dynamical system. In this method, the projections (PCs) of the image of a test point with misalignment onto the nonlinear principal components in normal condition in featured space F are computed to represent the misalignment characteristics. It is shown in this work that the exploitation of the projections combination can improve the detection results. Even the varying trends of misalignment fault could be identified by use of this detection method. The method is illustrated on an experimental example of an auxiliary magnetic bearing rotor system.

Sediment amendments provide promising strategies of enhancing sequestration of heavy metals and degradation of organic contaminants. The impacts of sediment amendments for metal and organic remediation including apatite, organoclay (and apatite and organoclay in geotextile mats), acetate, and chitin on environmental microbial communities in overlying water and sediment profiles are reported here. These experiments were performed concurrent with an ecotoxicity evaluation (data submitted in companion paper) and X-ray absorption spectroscopy of zinc speciation post apatite amendments. X-ray absorption spectra showed that a modest modification of zinc speciation occurred in amended treatments. Significant changes in both bacterial cell densities and populations were observed in response to amendments of apatite+organoclay, chitin, and acetate. The enriched bacteria and breakdown of these amendments were likely attributed to water quality degradation (e.g. ammonia and dissolved oxygen). Molecular fingerprints of bacterial communities by denaturant gradient gel electrophoresis (DGGE) showed that distinct bacterial populations occurred in overlying waters from different amendments: apatite+organoclay led to the dominance of Gammaproteobacteria, acetate enriched Alphaproteobacteria, and chitin treatment led to a dominance of Bacteroidetes and Alphaproteobacteria. In amended sediments, Firmicutes, Bacteroidetes, and Deltaproteobacteria (Desulfovibrio) were commonly found with chitin and apatite+chitin treatments. Finally, sulfate-reducing bacteria (e.g. Desulfovibrio) and metal-reducing bacteria were also recovered with most probable number (MPN) analyses in treatments with acetate, chitin, and apatite+chitin. These geochemically important bacteria were stimulated by amendments and may play critical functional roles in the metal and organic contaminant remediation process for future investigations of contaminated sediments.

A novel high efficiency nanocomposite sorbent for CO2 capture has been developed based on oligomeric amine (polyethylenimine, PEI, and tetraethylenepentamine, TEPA) functionalized mesoporous silica capsules. The newly synthesized sorbents exhibit extraordinary capture capacity up to 7.9 mmol g−1 under simulated flue gas conditions (pre-humidified 10% CO2). The CO2 capture kinetics were found to be fast and reached 90% of the total capacities within the first few minutes. The effects of the mesoporous capsule features such as particle size and shell thickness on CO2 capture capacity were investigated. Larger particle size, higher interior void volume and thinner mesoporous shell thickness all improved the CO2 capacity of the sorbents. PEI impregnated sorbents showed good reversibility and stability during cyclic adsorption–regeneration tests (50 cycles).

Background Carbohydrates are a primary source of carbon and energy for many bacteria. Accurate projection of known carbohydrate catabolic pathways across diverse bacteria with complete genomes constitutes a substantial challenge due to frequent variations in components of these pathways. To address a practically and fundamentally important challenge of reconstruction of carbohydrate utilization machinery in any microorganism directly from its genomic sequence, we combined a subsystems-based comparative genomic approach with experimental validation of selected bioinformatic predictions by a combination of biochemical, genetic and physiological experiments. Results We applied this integrated approach to systematically map carbohydrate utilization pathways in 19 genomes from the Shewanella genus. The obtained genomic encyclopedia of sugar utilization includes ~170 protein families (mostly metabolic enzymes, transporters and transcriptional regulators) spanning 17 distinct pathways with a mosaic distribution across Shewanella species providing insights into their ecophysiology and adaptive evolution. Phenotypic assays revealed a remarkable consistency between predicted and observed phenotype, an ability to utilize an individual sugar as a sole source of carbon and energy, over the entire matrix of tested strains and sugars. Comparison of the reconstructed catabolic pathways with E. coli identified multiple differences that are manifested at various levels, from the presence or absence of certain sugar catabolic pathways, nonorthologous gene replacements and alternative biochemical routes to a different organization of transcription regulatory networks. Conclusions The reconstructed sugar catabolome in Shewanella spp includes 62 novel isofunctional families of enzymes, transporters, and regulators. In addition to improving our knowledge of genomics and functional organization of carbohydrate utilization in Shewanella, this study led to a substantial expansion of our current version of the Genomic Encyclopedia of Carbohydrate Utilization. A systematic and iterative application of this approach to multiple taxonomic groups of bacteria will further enhance it, creating a knowledge base adequate for the efficient analysis of any newly sequenced genome as well as of the emerging metagenomic data.

The growth of the Semantic Web has seen a rapid increase in the amount of Semantic Web data. Meanwhile, the demand for access to Semantic Web data without detailed knowledge of RDF query languages is increasing. In this paper, an approach which can return ranked answers to keyword query without the help of data schema is proposed. With the proposed approach, Semantic Web data is modeled as RDF sentence graph, and an answer to a query is modeled as an RDF sentence tree containing all query keywords. We present an algorithm for searching top-k answers based on an indexing scheme, and employ IR-style scores in re-ranking answers. The experimental results show our approach is feasible and effective.

Various phthalates are used extensively as plasticizers in kinds of consumer products. They are harmful for human reproduction and fertility. Mono-(2-ethylhexyl) phthalate (MEHP) is the active metabolite of di-(2-ethylhexyl) phthalate(DEHP),which is most commonly used as a plasticizer and solvent in numerous consumer products. MEHP has been demonstrated to be a reproductive toxicant in rodents, but the evidences of using human cells are rare. In present study, we examined the effect of MEHP on viability and steroid production of human granulosa cells. Human granulosa cells obtained from nine patients undergoing in vitro fertilization were cultured in medium with various concentrations of MEHP (100,300,500 µmol L− 1). After culture for 48 hours, granulosa cells viability was determined. Estradiol, progesterone and testosterone were assayed in the spent culture medium. We found that the viability of granulosa cells was reduced obviously at 100, 300 and 500µmol L− 1 of MEHP. High concentration of MEHP(500uM) was harmfull to steriod hormone synthesis, such as estradiol and progestorone. These findings will provide favorable evidence for adverse effect of MEHP on women's reproductive system.

The regional economic disparity is always a research hot spot to domestic and foreign scholars. In this paper, the Beijing-Tianjin-Hebei metropolitan region was taken as research object; methods of exploratory spatial data analysis and spatial autocorrelation model provide new insights to explore spatial dependence relation of JingJinJi Metropolitan Region over the 2001–2006 periods. Through spatial trend and character analysis, the Trend Info TuPu of GDP and population in this region was created. Furthermore, the certificated spatial data analysis method was introduced to construct the fit spatial relation model for the economic growth process, including spatial error model (SRM), spatial lag model (SLM), to further confirmed the spatial relation effect in the regional economic growth.

The spatio-temoral characteristics of statistical data was research challenges in Statistical GIS. In this paper, give an effective method to implement spatio-temporal organization and query of statistical data. First, introducing the research situation of spatio-temporal data model and analyzing the spatio-temporal feature of statistical data. Then proposing a data model using object-oriented method and introduce how to realize it in the database. At last, introducing t some of the most common query algorithm in the Statistical GIS. Proved by programming realization, long-term statistical data can be effectively organized and stored in the database, spatio-temporal snapshot query and sequences query can be well executed in this way.

Bacteria of the genus Shewanella can thrive in different environments and demonstrate significant variability in their metabolic and ecophysiological capabilities including cold and salt tolerance. Genomic characteristics underlying this variability across species are largely unknown. In this study, we address the problem by a comparison of the physiological, metabolic, and genomic characteristics of 19 sequenced Shewanella species. We have employed two novel approaches based on association of a phenotypic trait with the number of the trait-specific protein families (Pfam domains) and on the conservation of synteny (order in the genome) of the trait-related genes. Our first approach is top-down and involves experimental evaluation and quantification of the species’ cold tolerance followed by identification of the correlated Pfam domains and genes with a conserved synteny. The second, a bottom-up approach, predicts novel phenotypes of the species by calculating profiles of each Pfam domain among their genomes and following pair-wise correlation of the profiles and their network clustering. Using the first approach, we find a link between cold and salt tolerance of the species and the presence in the genome of a Na+/H+ antiporter gene cluster. Other cold-tolerance-related genes include peptidases, chemotaxis sensory transducer proteins, a cysteine exporter, and helicases. Using the bottom-up approach, we found several novel phenotypes in the newly sequenced Shewanella species, including degradation of aromatic compounds by an aerobic hybrid pathway in Shewanella woodyi, degradation of ethanolamine by Shewanella benthica, and propanediol degradation by Shewanella putrefaciens CN32 and Shewanella sp. W3-18-1. Electronic supplementary material The online version of this article (doi:10.1007/s10142-009-0142-y) contains supplementary material, which is available to authorized users.

Resource conflict is an outstanding problem in concurrent multiple projects with sharing a common and limited resource pool, and it often results in lower performance of these projects. Therefore, it is important and urgent to find an effective method for scheduling multiple projects with limited resources. A mathematical model for the multi-project scheduling problem with resource-constrained is proposed, and a scheduling algorithm based on greedy strategy for the problem is analyzed. Its application in real projects and comparison with other scheduling schemes proves that the algorithm is feasible.

With the rapid development of urban, city space extended from surface to subsurface. As the important data source for the representation of city spatial information, 3D city spatial data have the characteristics of multi-object, heterogeneity and multi-structure. It could be classified referring to the geo-surface into three kinds: above-surface data, surface data and subsurface data. The current research on 3D city spatial information system is divided naturally into two different branch, 3D City GIS (3D CGIS) and 3D Geological Modeling (3DGM). The former emphasizes on the 3D visualization of buildings and the terrain of city, while the latter emphasizes on the visualization of geological bodies and structures. Although, it is extremely important for city planning and construction to integrate all the city spatial information including above-surface, surface and subsurface objects to conduct integral analysis and spatial manipulation.

pD* semantics extends the ‘if-semantics' of RDFS to a subset of the OWL vocabulary It leads to simple entailment rules and relatively low computational complexity for reasoning In this paper, we propose a forward-chaining reasoning algorithm to support RDFS entailments under the pD* semantics This algorithm extends the Sesame algorithm to cope with the pD* entailments In particular, an optimization to the dependent table between entailment rules is presented to eliminate much redundant inferring steps Finally, some test results are given to illustrate the correctness and performance of this algorithm.

With the rapid development of urban, city space extended from surface to subsurface. As the important data source for the representation of city spatial information, 3D city spatial data have the characteristics of multi-object, heterogeneity and multi-structure. It could be classified referring to the geo-surface into three kinds: above-surface data, surface data and subsurface data. The current research on 3D city spatial information system is divided naturally into two different branch, 3D City GIS (3D CGIS) and 3D Geological Modeling (3DGM). The former emphasizes on the 3D visualization of buildings and the terrain of city, while the latter emphasizes on the visualization of geological bodies and structures. Although, it is extremely important for city planning and construction to integrate all the city spatial information including above-surface, surface and subsurface objects to conduct integral analysis and spatial manipulation. However, either 3D CGIS or 3DGM is currently difficult to realize the information integration, integral analysis and spatial manipulation. Considering 3D spatial modeling theory and methodologies, an object-oriented 3D integral spatial data model (OO3D-ISDM) is presented and software realized. The model integrates geographical objects, surface buildings and geological objects together seamlessly with TIN being its coupling interface. This paper introduced the conceptual model of OO3D-ISDM, which is comprised of 4 spatial elements, i.e. point, line, face and body, and 4 geometric primitives, i.e. vertex, segment, triangle and generalized tri-prism (GTP). The spatial model represents the geometry of surface buildings and geographical objects with triangles, and geological objects with GTP. Any of the represented objects, no mater surface buildings, terrain or subsurface objects, could be described with the basic geometry element, i.e. triangle. So the 3D spatial objects, surface buildings, terrain and geological objects can be integrated together with the TIN being its coupling interface. The software system, Geomo 3D , based on OO3D-ISDM and an application case in the central business district (CBD) of municipal Beijing are introduced. The case shows that the potential applications of OO3D-ISDM and Geomo 3D in the domains of digital city, digital geotechnical engineering and digital mine.

A novel approach is reported for cell patterning based on addressable microheaters and a poly(N-isopropyl acrylamide) (pNIPAM) themoresponsive coating. This thermoresponsive coating is created by a radio frequency NIPAM plasma and is denoted as plasma polymerized NIPAM (ppNIPAM). Films of ppNIPAM with a good retention of monomer side-chain functionality are produced using low-power continuous plasma deposition. Cell adhesion and cell detachment tests indicate that the surface switches between adhesive and nonadhesive behaviors as a function of temperature. The use of a photolithographically fabricated microheater array allows the ppNIPAM transition to occur spatially under the control of individual heaters. This localized change in the surface adhesive behavior is used to direct site-specific cell attachment. Patterned adhesion of two types of cells has been visualized on the array through fluorescent markers. Applications for diagnostic devices, cell-based sensors, tissue engineering, and cell transfection are envisioned.

Programmable surface chemistry has been achieved by depositing a temperature sensitive polymer onto arrays of micro-fabricated metallic heaters. Activating a single heater causes a localized change in the device surface chemistry from non-fouling to fouling in an aqueous environment. Two types of proteins and two types of cells were used to demonstrate localized immobilization of proteins and cells on such surface. These experiments show, for the first time, selective cell attachments on thermally responsive polymer controlled by a micro heater array. It suggests a new approach to realize proteomic chips and cell chips.

Programmable surface chemistry has been achieved by depositing thermally responsive polymer (plasma polymerized N-isopropylacrylamide, ppNIPAM) onto arrays ofmicro-fabricated metallic heaters. Activating a single heater causes a localized change in the device surface chemistry from non-fouling to fouling in aqueous environment. Various proteins were used to demonstrate localized immobilization of proteins on the surface ofcoated micro-heater arrays. Additional uses ofthis technique include applications such as cell patterning, tissue engineering, self-assembly, etc.