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Wind power is a promising electricity source. Nevertheless, wind turbine blade icing can cause severe problems in turbine operation. In this study, SiO

When the viewers sitting around the table observe 3D images, the viewing direction is generally oblique and the viewpoints should be distributed as annular. In this paper, a tabletop integral imaging (II) three-dimensional (3D) display system based on annular point light sources is demonstrated, which can present 3D images to multiple viewers in a standard annular viewing area with oblique viewing direction. The proposed system consists of annular point light sources, a Fresnel lens, a lens array, a two-dimensional (2D) display panel, and a diffuser screen. Each point light source illuminates the Fresnel lens to form parallel light and then illuminates the lens array and the display panel. A viewing sub-area is generated at the position of the diffuser screen, in which the 3D images can be viewed. Multiple viewing sub-areas are created in a way of time-division multiplexing to form a 360° annular viewing area. Compared with the previous tabletop 3D display, the viewing area can be concentrated at an oblique angle near the tabletop. The experimental results demonstrate the feasibility of the tabletop II 3D display system.

Influenced by social progress, voluntary work has become a trend of social development. As an important human resource of the community, the role of volunteers merits closer attention. Human resource management of voluntary service is emphasized heavily by both public and private sectors. For voluntary organizations and managers, understanding the participation motivation and characteristics of volunteers would surely help to better understand volunteers. Due to the declining passion for participation in social service of the Macau youth, this study tried to understand the motivations of the Macau employed youth volunteers. It further classified the types of volunteers to provide references for volunteer recruitment, as well as improve the operation and management of relevant volunteer departments and organizations.

The paper introduces the application of hydraulic model in environmental problems, discusses several examples using hydraulic model in environmental problems and several important factors in the process of the use of hydraulic model to study the water environment pollution simulation, which involves abnormal model, the transverse diffusion coefficient, pollutant simulation and so on. The applicable conditions, constraints and their possible solutions of this technology are also discussed.

This paper is to propose a method of ecological carbon sink regionalization in the view of GHG (greenhouse gas) emission reduction, which could provide scientific theory basis for development and utilization of urban land resources, ecological environment construction, biodiversity conservation, the industry layout and formulation of the regional sustainable development strategy. Based on the existing researches foundation, this study takes Shenzhen as a typical case to put forward a method for carbon sink regionalization of urban land use with further quantitative evaluation of ecosystem carbon storage (density), carbon sources/sinks function and carbon sink potential of Shenzhen city. The results show that: Shenzhen ecological carbon sink is regionalized into six categories 55 regions, including 15 intensive carbon sink regions, 17 medium carbon sink regions, 10 weak carbon sink regions, 4 carbon neutral regions, 5 medium carbon source regions and 4 intensive carbon source regions.

The carbon emission caused by land use change is a human carbon source only second to fossil fuel combustion, the urbanization process in China is extremely intensified, which carbon emissions effect caused by land use change becomes a key factor to influence China's target of carbon emission reduction. Taken Shenzhen city as a typical case, this study utilizes unit root and co-integration test method to research existence of carbon emissions EKC (Environmental Kuznets Curve) in Shenzhen on the basis of the carbon emissions EKC theory and land-use carbon emissions data of 1979-2010 years, in combination with the existing research foundation. The result proves that, the carbon emission EKC per capita exists in Shenzhen, and the inflection point time of carbon emissions per capita is also calculated for Shenzhen city, which provides new research ideas and scientific guidance for urban carbon emission reduction in China.

IBIS (Integrated Biosphere Simulator) model is an ecosystem process model, which represents the research direction of a global carbon cycle simulation. Based on the existing research achievements, the regional ecological carbon sink potential is simulated from point to surface with a long time serie of meteorological data (1954-2010), data on different ecosystem vegetation types, soil texture data, terrain data and remote sensing data. The results are listed as follows: there is no significant variation of potential carbon sink of Shenzhen vegetation over the past 30 years, carbon sequestration caapcity ranges within 43.52-55.82×104Mg C/a, and the potential carbon sink intensity value within 0-624 C/m2/a. Precipitation is a main factor which influnces the ecosystem carbon sink intensity in Shenzhen City. The carbon sink intensity of ecosystem is increased with more annual precipitation.

This study combines the sampling technique, geographic information system and remote sensing technique to conduct a sampling survey on forest cover area of Jinggangshan National Nature Reserve in China on the basis of TM remote sensing image. The spatial simple random sampling, spatial stratified sampling and sandwich sampling model are respectively utilized to establish the sampling design. For the spatial simple random sampling model, the spatial autocorrelation analysis method is adopted to determine the spatial autocorrelation coefficient through calculating Moran's I index, while in the spatial stratified sampling and sandwich sampling model, the yearly maximum NDVI (Normalized Difference Vegetation Index) is utilized to conduct the spatial stratification. Through comparison of the sampling accuracy of three sampling models, a higher precision and more reasonable sampling method and sampling model is provided for remote sensing monitoring of forest cover area. The study results show that: sandwich sampling model is featured as the highest sampling accuracy, followed by the spatial stratified sampling and simple random sampling. Under the requirement of same precision, sandwich spatial sampling model can reduce quantity of the sampling points, and create all kinds of report units according to demands of different spatial area, so it is featured as the better suitability.

The construction of a normalized cDNA library is a popular tool for identifying novel biomarkers for monitoring environmental pollution. In the present study, a normalized cDNA library was constructed from the river snail Bellamya aeruginosa after exposure to Cu(2+) by using the SMART technique. The titer of the cDNA library was 1.78 × 10(6) pfu/ml, with a recombinant efficiency of 95.8%. In addition, from 6,000 randomly selected and sequenced clones, 5,473 high-quality ESTs were identified. After processing the sequences, 3,961 unigenes representing 897 contigs and 3,064 singlets were obtained with 27.6% redundancy. Analysis of expressed sequenced tags using COG and GO annotation and KEGG pathway data showed that a large group of genes related to growth and development, signal transduction, and defense mechanisms were present in the cDNA library. Based on our findings, this normalized cDNA library will provide a valuable resource for further research on functional genes and ecotoxicology in B. aeruginosa.

The effects of terrestrial carbon cycle caused by Land use change on are obvious. Urbanization is an important reason of land use change. Based on the soil and plant data that field sampled, five remote sensing data of 1979, 1989, 1995, 2000 and 2003, the effects on ecosystem organic carbon pool from1979 to 2003 caused by land use change in Shenzhen city are analyzed. The land use changes are mainly occurred between the following 8 land types, farmland, wood land, grass land and construction land. The results show that form 1979 to 2003 carbon emissions caused by land use change in Shenzhen City totally reduced by 337.24 × 104Mg C (1Mg C = 1 × 106g C). The average annual carbon emissions arrive up to 24.09 × 104Mg C. Among them, the emissions caused by the reductions of farmland and forest area are respectively 252.26 × 104Mg C and 111.73 × 104Mg C. The organic carbon increment caused by garden land increase is 47.37 × 104Mg C. The results show that Urbanization process totally is a carbon sink process. The study is valuable for assessing the relations between carbon effects and land development and ecological restoration planning in the process of rapid urbanization.

Land-use and land-cover change (LUCC) is an important factor of global change. In this study, the LUCC of Liaoning Coastal Economic Zone, the typical area of urbanization in China, was simulated by applying CLUE-S model under the historical trend scenario and policy scenario two scenarios. Transfer matrix and landscape index were also applied to analyze the change of landscape pattern. The results show that, from 1988 to 2007, the area of construction land was considerably increased. However, the area of forest, water and farmland were greatly decreased. The results were mainly caused by the rapid growth of economic, population and accelerated urbanization. These changes have caused landscape fragmentation in this study area. In general, the trends of landscape changes under two scenarios were unsustainable in this area.

We propose self-adaptive finite element methods with error control for solving elliptic and electromagnetic problems with discontinuous coefficients. The meshes in the methods do not need to fit the interfaces. New error indicators are introduced to control the error due to non-body-fitted meshes. Flexible h-adaptive strategies are developed, which can be systematically extended to a large class of interface problems. Extensive numerical experiments are performed to support the theoretical results and to show the competitive behavior of the adaptive algorithm even for interfaces involving corner or tip singularities.

Consistent NDVI time series are basic and prerequisite in long-term monitoring of land surface properties. Advanced very high resolution radiometer (AVHRR) measurements provide the longest records of continuous global satellite measurements sensitive to live green vegetation, and moderate resolution imaging spectroradiometer (MODIS) is more recent typical with high spatial and temporal resolution. Understanding the relationship between the AVHRR-derived NDVI and MODIS NDVI is critical to continued long-term monitoring of ecological resources. NDVI time series acquired by the global inventory modeling and mapping studies (GIMMS) and Terra MODIS were compared over the same time periods from 2000 to 2006 at four scales of Qinghai-Tibet Plateau (whole region, sub-region, biome and pixel) to assess the level of agreement in terms of absolute values and dynamic change by independently assessing the performance of GIMMS and MODIS NDVI and using 495 Landsat samples of 20 km x20 km covering major land cover type. High correlations existed between the two datasets at the four scales, indicating their mostly equal capability of capturing seasonal and monthly phenological variations (mostly at 0. 001 significance level). Simi- larities of the two datasets differed significantly among different vegetation types. The relative low correlation coefficients and large difference of NDVI value between the two datasets were found among dense vegetation types including broadleaf forest and needleleaf forest, yet the correlations were strong and the deviations were small in more homogeneous vegetation types, such as meadow, steppe and crop. 82% of study area was characterized by strong consistency between GIMMS and MODIS NDVI at pixel scale. In the Landsat NDVI vs. GIMMS and MODIS NDVI comparison of absolute values, the MODIS NDVI performed slightly better than GIMMS NDVI, whereas in the comparison of temporal change values, the GIMMS data set performed best. Similar with comparison results of GIMMS and MODIS NDVI, the consistency across the three datasets was clearly different among various vegetation types. In dynamic changes, differences between Landsat and MODIS NDVI were smaller than Landsat NDVI vs. GIMMS NDVI for forest, but Landsat and GIMMS NDVI agreed better for grass and crop. The results suggested that spatial patterns and dynamic trends of GIMMS NDVI were found to be in overall acceptable agreement with MODIS NDVI. It might be feasible to successfully integrate historical GIMMS and more recent MODIS NDVI to provide continuity of NDVI products. The accuracy of merging AVHRR historical data recorded with more modern MODIS NDVI data strongly depends on vegetation type, season and phenological period, and spatial scale. The integration of the two datasets for needleleaf forest, broadleaf forest, and for all vegetation types in the phenological transition periods in spring and autumn should be treated with caution.

Lung cancer is the most dreaded of all cancers because of the higher mortality rates associated with it worldwide. The various subtypes of lung cancer respond differently to a particular treatment regime, which makes the therapeutic interventions all the more complicated. The concept of cancer stem cells (CSCs) is based primarily on the clinical and experimental observations that indicate the existence of a subpopulation of cells with the capacity to self-renew and differentiate as well as show increased resistance to radiation and chemotherapy. They are considered as the factors responsible for the cases of tumor relapse. The CSCs may have significant role in the development of lung tumorigenesis based on the identification of the CSCs which respond during injury. The properties of multi-potency and self-renewal are shared in common by the lung CSCs with the normal pluripotent stem cells which can be isolated using the similar markers. This review deals with the origin and characteristics of the lung cancer stem cells. The role of different markers used to isolate lung CSCs like CD44, ALDH (aldehyde dehydrogenase), CD133 and ABCG2 (ATP binding cassette sub family G member 2) have been discussed in detail. Analysis of the developmental signaling pathways such as Wnt/β-catenin, Notch, hedgehog in the regulation and maintenance of the lung CSCs have been done. Finally, before targeting the lung CSC biomarkers for potential therapeutics, challenges faced in lung cancer stem cell research need to be taken into account. With the accepted notion that the CSCs are to blame for cancer relapse and drug resistance, targeting them can be an important aspect of lung cancer therapy in the future.

In response to ionizing irradiation and certain chemotherapeutic agents, dying tumor cells elicit a potent anticancer immune response. However, the potential effect of wogonin (5,7-dihydroxy-8-methoxyflavone) on cancer immunogenicity has not been studied. Here we demonstrated for the first time that wogonin elicits a potent antitumor immunity effect by inducing the translocation of calreticulin (CRT) and Annexin A1 to cell plasma membrane as well as the release of high-mobility group protein 1 (HMGB1) and ATP. Signal pathways involved in this process were studied. We found that wogonin-induced reactive oxygen species (ROS) production causes an endoplasmic reticulum (ER) stress response, including the phosphorylation of PERK (PKR-like endoplasmic reticulum kinase)/PKR (protein kinase R) and eIF2α (eukaryotic initiation factor 2α), which served as upstream signal for the activation of phosphoinositide 3-kinase (PI3K)/AKT, inducing calreticulin (CRT)/Annexin A1 cell membrane translocation. P22/CHP, a Ca(2+)-binding protein, was associated with CRT and was required for CRT translocation to cell membrane. The releases of HMGB1 and ATP from wogonin treated MFC cells, alone or together with other possible factors, activated dendritic cells and induced cytokine releases. In vivo study confirmed that immunization with wogonin-pretreated tumor cells vaccination significantly inhibited homoplastic grafted gastric tumor growth in mice and a possible inflammatory response was involved. In conclusion, the activation of PI3K pathway elicited by ER stress induced CRT/Annexin A1 translocation ("eat me" signal) and HMGB1 release, mediating wogonin-induced immunity of tumor cell vaccine. This indicated that wogonin is a novel effective candidate of immunotherapy against gastric tumor.

A multigrid solver for the steady incompressible Navier-Stokes equations on a curvilinear grid is constructed. The Cartesian velocity components are used in the discretization of the momentum equations. A staggered, geometrically symmetric distribution of velocity components is adopted which eliminates spurious pressure oscillations and facilitates the transformation between Cartesian and co-or contravariant velocity components. The SCGS (symmetrical collective Gauss-Seidel) relaxation scheme proposed by Vanka on a Cartesian grid is extended to this case to serve as the smoothing procedure of the multigrid solver, in both "box" and "box-line" versions. Due to the symmetric distribution of velocity components of this scheme, the convergence rate and numerical accuracy are not affected by grid orientation, in contrast to a scheme proposed in the literature in which difficulties arise when the grid lines turn 90° from the Cartesian coordinates. Some preliminary numerical experiences with this scheme are presented.

A new synthetic flavonoid DHF-18, synthesized with a piperazine substitution, has been recently found to show potent anti-tumor activities both in vivo and in vitro. In this study, we demonstrated that DHF-18 significantly inhibited tumor growth in mice inoculated with Heps hepatoma cells without evident toxicity. After the treatment of 40mg/kg DHF-18, the inhibitory rate of tumor weight was 53.69%. To investigate whether apoptosis induction contributed to the anti-tumor effects of DHF-18, DAPI (diamidino-phenyl-indole) staining and Annexin V/PI (Propidium iodide) double staining were performed in our tests. The data showed that DHF-18 could induce the apoptosis cell death in HepG2 cells. Moreover, the apparent increase of intracellular reactive oxygen species levels and the reduction of mitochondria ΔΨm were both observed in HepG2 cells after DHF-18 treatment. Meanwhile, the transposition of apoptotic inducing factor (AIF) from mitochondria to nuclei, the release of cytochrome c from mitochondria and the activation of caspase-3, -9 were also detected, indicating that DHF-18 may induce apoptosis through a mitochondrial-mediated pathway. Additionally, DHF-18 decreased the expression of Bcl-2 protein, whereas the levels of Bax and Bak were found to increase after DHF-18 treatment. Moreover, the activation of caspase-8, the increase of TNF-R1 (Tumor necrosis factor receptor) and Bid were found. Taken together, our results suggested that DHF-18 may induce HeG2 cells apoptosis through a mitochondrial-dependent and independent pathway.

In this review of methods for purity assessment of isolated chromosome X- and Y-bearing sperm, we compared the principles, operating procedures, as well as pros and cons for various methods. We conclude that nested PCR of single sperm will become a conventional and popular method with lower costs, and the method will play a very important role in optimizing the X, Y sorting method, if the sensitivity and accuracy of the method can be increased and the testing time decreased, and promote the new progress in other genetic testing techniques on single sperm.

In this paper, a triple-band planar absorber with high-impedance surface (HIS) is designed and fabricated. The absorber structure is composed of polyurethane foam sandwiched between a lossy sheet of frequency selective surfaces (FSS) and a perfect electric conductor. The lossy FSS possesses different resistances in a periodic composite unit as compared with typical HIS absorber. Losses in the FSS are introduced by printing the periodic composite square ring pattern on blank stickers using various resistive inks. Physical mechanism of the HIS absorbers is analyzed by equivalent circuit model and electric field distribution studies. The proposed absorber with periodic composite units offers superimposed triple-band absorption as compared with that of the single units having single- or dual-band absorption characteristics. The reflection loss measurements show that the 90% absorption bandwidth of the HIS absorber is increased by 42% by the proposed composite periodic units.

AIM: To evaluate the effects of self-expanding metal stents (SEMS) in patients with malignant esophageal obstruction and to analyze their prognosis and complications. METHODS: Seventy-four metallic stents were placed under fluoroscopic guidance in 66 patients with esophageal obstruction secondary to carcinoma, of whom, 6 cases were complicated by fistula. RESULTS: After seventy-two stents were successfully used in 66 cases without any severe complications (technical successful rate was 97%), the dysphagia score improved from 3.3±0.6 to 0.8±0.5 (P