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Due to the complexity of geological structures, the uncertainty of geological phenomena, the massive amount of geological data, and the diversity of geological models, local dynamic updates of 3D geological body models are very difficult. Based on the analysis of the current research status of 3D geological modeling and local dynamic update of 3D geological body model, the local dynamic update methods of geological body models considering geometric, topological, semantic relationships, and geological feature features for different data sources based on the B-Rep (boundary representation) structure model and the CPG (corner-point grid) voxel model are studied in this paper. The local dynamic update methods for the 3D geological bodies based on the B-Rep structure model for new local drilling and profile data are proposed and implemented. There are two local dynamic update methods. The Dynamic update method of B-Rep structure model for local new borehole data is used to update the 3D geological body structure model to comply with the new borehole constraints. The dynamic update method of B-Rep structure model for local new profile data is used to update to the 3D geological body structure model to comply with the new profile constraints. Also the local dynamic update methods for 3D geological bodies based on the CPG voxel model for local new drilling data, new profile data, and new multi-source mixed data are proposed and implemented. There are three local dynamic update methods. The dynamic update method of CPG voxel model for local new borehole data is used to update the 3D geological body CPG voxel model to comply with the new borehole without considering the special topological changes between the strata. The dynamic update method of CPG voxel model for local new profile data is used to update the 3D geological body CPG voxel model to comply with the new profile without considering the fault information. The dynamic update method of CPG voxel model for multi-source mixed data is used to update the 3D geological body CPG voxel model to comply with the new local data through the idea of local voxel replacement with considering the faults information and special topological changes. Finally, dynamic updates for different algorithms and comparative analysis were completed through experiments. [ABSTRACT FROM AUTHOR]

Integrating a 3D geological model into the virtual Earth environment enables the display of the geological model on a larger scale, making the surrounding terrain and landform more intuitive, and improving the accuracy of geological research. Because the section analysis of 3D geological model can clearly show the geological structure and attribute information on a section, it is a popular analysis method for geologists. However, the existing methods based on Boolean operations have high requirements on the topological relationship of the model, and their efficiency and accuracy are not ideal when faced with complex 3D geological models. Meanwhile, traditional rendering-based methods can only obtain pixel-level sectional results, making measurement difficult. This paper proposes a cutting analysis algorithm for 3D geological model in virtual earth environment. This method utilizes hierarchical bounding volume (BVH) and ray intersection algorithm to extract formation boundary data, avoiding complex Boolean operations and improving the efficiency of section analysis. Furthermore, using these data to draw measurable geological section maps effectively solves the problem that the section results cannot be measured. This method can be used to quickly and effectively obtain a section diagram the conforms to the standard diagram legend, which can be directly used in the preparation of geological analysis reports. The feasibility of this method is verified by taking the section analysis of a complex 3D geological model in a certain area as an example. [ABSTRACT FROM AUTHOR]

As selection of landslide-causing indicators and training samples in landslide susceptibility assessment are the key factors in determining a model's accuracy, the purpose of this research is to improve the accuracy of the landslide susceptibility assessment model by streamlining landslide-causing indicators and expanding training samples. To this end, rough set (RS) theory and genetic reduction method are adopted to reduce the initial 15 landslide-related indicators to 8 indicators highly correlated to landslide occurrence. Then, to tackle the problem of insufficient training samples, a semi-supervised classification method is employed to train the model classifier using labeled data and unlabeled data as mixed samples. Upon these, the landslide susceptibility assessment model of RS-SSVM is set up, with landslide susceptibility grades divided into high, medium, low, and non-prone zones in Qinzhou. Finally, the area under curve (AUC) values are used to compare and validate performances for different models. Analysis and comparison of the results denotes that the RS-SSVM method performed well as indicated by the AUC values of training datasets and verification datasets being 0.9308 and 0.9116. Meanwhile, the AUC values of RS-SSVM and SSVM are 0.9116 and 0.8522, respectively. This indicates that selecting more landslide-causing indicators does not necessarily bring better accuracy; instead, only the key impact indicators should be selected. Furthermore, overlay statistical analysis using historical landslide inventory data and assessment results shows that 71.27% of the historical landslides sites are in the high susceptibility areas accounting for 2.96% of the total area of the study area, which agrees well with the distribution features of historical landslides. Therefore, the proposed RS-SSVM method can improve the spatial cognition of the complex landslide systems aside from being applied to landslide susceptibility assessment in other places with similar regional geo-environmental conditions. [ABSTRACT FROM AUTHOR]

How to reconstruct a credible three-dimensional (3D) geological model from very limited survey data, e.g. boreholes, outcrop, and two-dimensional (2D) images, is challenging in the field of 3D geological modeling. Against the limitations of the huge computational consumption and complex parameterization of geostatistics-based stochastic simulation methods, we propose an automatic reconstruction method of 3D geological models based on deep convolutional generative adversarial network (DCGAN). In this work, 2D geological sections are used as conditioning data to generate 3D geological models automatically. Various realizations can be reproduced under a same DCGAN model established through deep network training. A U-Net structure is used to enhance the fitting effect of the DCGAN model. In addition, joint loss functions are exploited to increase the similarity between 3D realizations and reference models. Three synthetic datasets were used to verify the capability of the method presented in this paper. Experimental results show that the proposed 3D automatic reconstruction method based on DCGAN can capture the features, trends and spatial patterns of geological structures well. The output models obey the used conditioning data. The complex heterogeneous structures are reconstructed more accurately and quickly by using the proposed method. [ABSTRACT FROM AUTHOR]

Albino tea plants generally have higher theanine, which causes their tea leaves to taste fresher, and they are an important mutant for the breeding of tea plant varieties. Earlier, we reported an albino germplasm, 'Menghai Huangye' (MHHY), from Yunnan Province and found that it has a lower chlorophyll content during the yellowing stage, but the mechanism underlying low chlorophyll and the yellowing phenotype is still unclear. In this study, the pigment contents of MHHY_May (yellowing, low chlorophyll), MHHY_July (regreening, normal chlorophyll), and YK10_May (green leaves, normal chlorophyll) were determined, and the results showed that the lower chlorophyll content might be an important reason for the formation of the yellowing phenotype of MHHY. Through transcriptome sequencing, we obtained 654 candidates for differentially expressed genes (DEGs), among which 4 genes were related to chlorophyll synthesis, 10 were photosynthesis-related, 34 were HSP family genes, and 19 were transcription factor genes. In addition, we analysed the transcription levels of the key candidate genes in MHHY_May and MHHY_July and found that they are consistent with the expression trends in MHHY_May and YK10_May, which further indicates that the candidate differential genes we identified are likely to be key candidate factors involved in the low chlorophyll content and yellowing of MHHY. In summary, our findings will assist in revealing the low chlorophyll content of MHHY and the formation mechanism of yellowing tea plants and will be applied to the selection and breeding of albino tea cultivars in the future. [ABSTRACT FROM AUTHOR]

Geo-environmental information is an important basis for geohazard analysis and the integration of geo-environmental data is crucial in the construction of urban emergency management systems. In existing urban spatial information systems, the integration of geo-environmental data is neither intuitive nor efficient enough to support the analysis of geohazards well. On the basis of Web virtual globe, this paper proposes a comprehensive framework for the integration and analysis of geo-environmental data. This framework can effectively integrate geological data with a 3D geological model as a carrier, seamlessly connect geographic data, dynamically load real-time monitoring data, and build 3D visualisation and analysis scenes of urban full-space temporal information in the browser. The application example shows that the proposed framework can provide good geo-environmental data and practical data analysis functions for geohazard early warning and decision making, and improve the efficiency of government departments' response to geohazards. [ABSTRACT FROM AUTHOR]

The construction of a large-scale integrated information system has been a hot issue in the field of geoinformatics. It aims to integrate aboveground and underground spatial information and objects in a unified visual environment. Virtual globe, as the most commonly used technology in the construction of Digital Earth, can provide a platform and framework for the integration and visualization of worldwide spatial objects and models. However, the existing works mainly focused on terrains and aboveground spatial entities, and there is still little research on the integration and visualization of large-scale underground geological models and entities in a virtual globe. In this work, the data organizations of aboveground and underground 3D spatial objects were analyzed in detail according to the technical characteristics of the virtual globe. Improved strategies were proposed to achieve the integrated visualization of aboveground and underground 3D spatial objects in a virtual globe-based spherical coordinate. In this process, the terrain surface based on Triangulated Irregular Network (TIN) was used as an intermediate layer to unify the spatial coordinate system. An improved scene cutting approach was used to overcome the challenge that underground geological structures cannot be integrated and visualized with aboveground spatial entities, terrains and landforms. Finally, we developed a virtual globe-based prototype system using OpenSceneGraph (OSG) and osgEarth as the 3D visualization engine. The aboveground and underground spatial models of Fuzhou, a coastal city of eastern China, were applied in this system to verify the validity of the strategies proposed in this paper. In addition, the efficiency of this system in terms of scheduling and visualizing was tested by using the massive models of Fuzhou. [ABSTRACT FROM AUTHOR]

The performance of reactive oxygen species generator is low in the large-scale application because of the lower operating frequency determined by geometrical scale amplification effect. This paper proposes a method named partitioned operation method whereby the resonance frequency can be kept even if the number of reactor modules increases. The idea is to use n number of low-power high-frequency transformers instead of conventional high-power transformer. One low-power high-frequency transformer and one reactor module constitute a partitioned operation unit, then n number of the partitioned operation units are connected to an inverter, with each unit designed to operate at its optimum operating frequency. The main advantage of the proposed method is to keep the resonance frequency when the number of reactor modules is increased. In addition, the discharge system is very flexible because the number of partitioned operation units can be added or removed as demanded by the ROS generation. In this study, a ROS generator included twenty-four reactor modules was designed and implemented for confirming the feasibility of partitioned operation method. Results show that the efficiency of ROS generation did not decline with the increase of reactor module number. [ABSTRACT FROM AUTHOR]

Movement is a complex process that evolves through both space and time. Movement data generated by moving objects is a kind of big data, which has been a focus of research in science, technology, economics, and social studies. Movement database is also at the forefront of geographic information science research. Developing efficient access methods for movement data stored in movement databases is of critical importance. Tree-like indexing structures such as the R-tree, Quadtree, Octree are not suitable for indexing multi-dimensional movement data because they all have high space cost of their inner nodes. In addition, it is difficult to use them for parallel access to multi-dimensional movement data because they thereof, are in hierarchical structures, which have severe overlapping problems in high dimensional space. In this paper, we propose a novel access method, the Decomposition Tree (D-tree), for indexing multi-dimensional movement data. The D-tree is a virtual tree without inner nodes, instead, through an encoding method based on integer bit-shifting operation, and can efficiently answer a wide range of queries. Experimental results show that the space cost and query performance of D-tree are superior to its best known competitors. [ABSTRACT FROM AUTHOR]

An innovative and removable water treatment system consisted of strong electric field discharge and hydrodynamic cavitation based on advanced oxidation technologies was developed for reactive free radicals producing and waterborne pathogens eliminating in the present study. The biological efficacy and toxic effects of this advanced oxidation system were evaluated during water disinfection treatments. Bench tests were carried out with synthetic microbial-contaminated water, as well as source water in rainy season from a reservoir of Dalian city (Liaoning Province, China). Results showed that high inactivation efficiency of Escherichia coli (>5 log) could be obtained for synthetic contaminated water at a low concentration (0.5-0.7 mg L) of total oxidants in 3-10 s. The numbers of wild total bacteria (108 × 10 CFU mL) and total coliforms (260 × 10 MPN 100 mL) in source water greatly reduced to 50 and 0 CFU mL respectively after treated by the advanced oxidation system, which meet the microbiological standards of drinking water, and especially that the inactivation efficiency of total coliforms could reach 100 %. Meanwhile, source water qualities were greatly improved during the disinfection processes. The values of UV in particular were significantly reduced (60-80 %) by reactive free radicals. Moreover, the concentrations of possible disinfection by-products (formaldehyde and bromide) in treated water were lower than detection limits, indicating that there was no harmful effect on water after the treatments. These investigations are helpful for the ecotoxicological studies of advanced oxidation system in the treatments of chemical polluted water or waste water. The findings of this work suggest that the developed water treatment system is ideal in the acute phases of emergencies, which also could offer additional advantages over a wide range of applications in water pollution control. [ABSTRACT FROM AUTHOR]

Dual specificity phosphatase 22 (DUSP22) is a novel dual specificity phosphatase that has been demonstrated to be a cancer suppressor gene associated with numerous biological and pathological processes. However, little is known of DUSP22 expression profiling in colorectal cancer and its prognostic value. Our study aims to investigate the role of DUSP22 expression in the prognosis of colorectal cancer. We detected the mRNA expression in 92 paired primary colorectal cancer tissues and the corresponding adjacent normal tissues by using QuantiGenePlex assay. The Friedman test was used to determine the statistical difference of gene expression. Kaplan-Meier survival analysis was performed. Mann-Whitney test and Kruskal-Wallis test were used to conduct data analyses to determine the prognostic value. Statistical significance was set at P < 0.05. In 74 of 92 cases, DUSP22 mRNA was reduced in primary colorectal cancer tissues, compared to the adjacent normal tissues. The mRNA levels of DUSP22 were significantly lower in colorectal cancer tissues than in adjacent normal tissues (0.0290 vs. 0.0658; P < 0.001). Low expression of DUSP22 correlated significantly with large tumor size ( P = 0.013). No association was observed between DUSP22 mRNA expression and differentiation, histopathological type, tumor invasion, lymph node metastases, metastases, TNM stage, and Duke's phase (all P > 0.05). Kaplan-Meier analysis indicated that DUSP22 expression had no significant relationship with overall survival in all patients ( P > 0.05). Interestingly, low expression level of DUSP22 in stage IV patients had a poor survival measures with a marginal P value ( P = 0.07). Reduced DUSP22 expression was found in colorectal cancer specimens. Low expression level of DUSP22 in stage IV patients had a poor survival outcome. Further study is required for the investigation of the role of DUSP22 in colorectal cancer. [ABSTRACT FROM AUTHOR]

A novel discharge mode consisting of alternate discharge of a micro-streamer and micro-glow was developed to induce the formation of ·OH radicals in ballast water. A series of ·OH killing experiments were then conducted using medium salinity ballast water. Five species of algae from three different phyla and three kinds of bacteria were killed by ·OH radicals in compliance with the D-2 ballast water standard of International Maritime Organization. Moreover, the chlorophyll- a was fully discolored when the total reactive oxidants was 2.5 mg/L, indicating that the algae had died. Overall, the quality of medium salinity ballast water with heavy pollution was greatly improved. These results indicate that the use of ·OH radicals is an effective method for the treatment of ship's ballast water. [ABSTRACT FROM AUTHOR]

The ballast water of oceanic ships is the main cause for worldwide transfer of non-indigenous aquatic species. The use of hydroxyl radicals is an efficient method for killing the aquatic species in ballast water. For practical application, a 250 t/h ·OH ballast water-treatment system was designed and installed on the ship Yulong (ten thousand tons) in Dalian harbor. On this ship, a series of experiments were carried out. As a result, the concentration of total oxidants declined over time. Harmful aquatic organisms and pathogens in the ballast water were rapidly killed after ·OH treatment and no re-growth was observed during a storage time of 5 days. The quality of the ballast water was considerably improved. Therefore, the D-2 ballast water discharge standard of the International Maritime Organization was satisfied. Compared with current methods, ·OH treatment is a potentially effective technology which can be practically applied in the ballast water-treatment of oceanic ships in the future. [ABSTRACT FROM AUTHOR]