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Polyamines are essential for the growth of eukaryotic cells and can be dysregulated in tumors. Here we describe a strategy to deplete polyamines through host–guest encapsulation using a peptide-pillar[5]arene conjugate (P1P5A, P1 = RGDSK(N3)EEEE) as a supramolecular trap. The RGD in the peptide sequence allows the molecule to bind to integrin αvβ3-overexpressing tumor cells. The negative charged glutamic acid residues enhance the inclusion affinities between the pillar[5]arene and cationic polyamines via electrostatic interactions and facilitate the solubility of the conjugate in aqueous media. The trap P1P5A efficiently encapsulates polyamines with association constants of 105–106 M−1. We show that P1P5A has a wide spectrum of antitumor activities, and induces apoptosis via affecting the polyamine biosynthetic pathway. Experiments in vivo show that P1P5A effectively inhibits the growth of breast adenocarcinoma xenografts in female nude mice. This work reveals an approach for suppressing tumor growth by using supramolecular macrocycles to trap polyamines in tumor cells., Polyamines are essential for cell growth and are frequently increased in concentration in cancer cells. Here, the authors use a macrocycle to generate a supramolecular trap, which depletes the polyamines in cells, induces apoptosis and reduces cancer cell growth in mice.

Gossypol was considered a promising male contraceptive but finally failed due to two side effects: hypokalemia and the irreversibility of its contraceptive effect. Here we demonstrate that sustained zero-order release could be a solution for these problems. The in vitro release of gossypol from gossypol/PEG layer-by-layer films follows a perfect zero-order kinetics. In vivo tests indicate that the films can maintain the plasma drug concentration constant in male SD rats for ∼20 days for a 30-bilayer film. The plasma drug concentration is 2 orders of magnitude lower than the peak plasma drug concentration when administered orally and the daily dose is50-fold lower than the commonly used contraceptive oral dose. However, significant antifertility effects were still observed. Furthermore, hypokalemia was not observed, and the antifertility effects can be reversed after a recovery period. The results suggest that zero-order release can significantly improve the desired antifertility effect of gossypol and, meanwhile, significantly reduce its side effects. We envision the drug could be developed to be an effective, safe, and reversible male contraceptive by zero-order release.

A novel hybrid manipulator is proposed and its kinematics and dynamics are analyzed systematically. First, a 3D prototype of the hybrid manipulator is constructed and analyzed. It is composed of a 5-DoF parallel manipulator with two equivalent composite universal joints and three fingers. Second, the kinematics formulae are established for solving the displacement, velocity and acceleration of the parallel manipulator and the finger mechanisms. Third, the dynamics formulae are derived for solving the dynamic active and constrained forces of the parallel manipulator and the finger mechanisms. Finally, a numerical example is given for solving the kinematics and the dynamics of the hybrid manipulator and the analytic solved results are verified by the simulation mechanism.

A responsive drug delivery system (DDS) for oxaliplatin (OX) has been designed with a view to overcoming several common drawbacks associated with this widely used anticancer agent, including fast degradation/deactivation in the blood stream, lack of tumor selectivity, and low bioavailability., A responsive drug delivery system (DDS) for oxaliplatin (OX) has been designed with a view to overcoming several drawbacks associated with this anticancer agent, including fast degradation/deactivation in the blood stream, lack of tumor selectivity, and low bioavailability. The present approach is based on the direct host–guest encapsulation of OX by a pH-responsive receptor, carboxylatopillar[6]arene (CP6A). The binding affinities of CP6A for OX were found to be pH-sensitive at biologically relevant pH. For example, the association constant (K a) at pH 7.4 [K a = (1.02 ± 0.05) × 104 M–1] is 24 times larger than that at pH 5.4 [K a = (4.21 ± 0.06) × 102 M–1]. Encapsulation of OX within the CP6A cavity did not affect its in vitro cytotoxicity as inferred from comparison studies carried out in several cancer cells (e.g., the HepG-2, MCF-7, and A549 cell lines). On the other hand, complexation by CP6A serves to increase the inherent stability of OX in plasma by 2.8-fold over a 24 h incubation period. The formation of a CP6A⊃OX host–guest complex served to enhance in a statistically significant way the ability of OX to inhibit the regrowth of sarcoma 180 (S180) tumors in Kunming (KM) mice xenografts. The improved anticancer activity observed in vivo for CP6A⊃OX is attributed to the combined effects of enhanced stability of the host–guest complex and the pH-responsive release of OX. Specifically, it is proposed that OX is protected as the result of complex formation and then released effectively in the acidic tumor environment.

The synthesis of 2,3-dihydro-pyrazines has been developed by an efficient protocol of annulations of 1,2-diketones and ethylenediamine. A variety of 2,3-dihydro-pyrazines were prepared in high yields in the presence of a catalytic amount of iodine.

The synthesis of 2,3-dihydro-pyrazines has been developed by an efficient protocol of annulations of 1,2-diketones and ethylenediamine. A variety of 2,3-dihydro-pyrazines were prepared in high yiel...

Biomass plays an important role in crop growth and yield formation. The study of biomass has been expanded to remote sensing sphere, which provides more ways to the obtainment of crop biomass. To carry out the study of winter wheat biomass estimation model, the field experiments were conducted at Rougu test area and Wugong test area, Shanxi Province in the cropping season 2013–2014. The biomass estimation model was based on the Time-Integrated Value of NDVI (TINDVI) and Leaf Water Content Index (LWCI), which was used to predict the winter wheat biomass. And the model was validated with the ground measured biomass. The results showed that the determination coefficient (R2) and root mean square error (RMSE) between the measured and the estimated biomass were 0.7949 and 2.689 t/ha, respectively. The estimated biomass was exactly similar to the field measured biomass, therefore this model had a good application prospect.

In this paper, the textural characteristics of the buildings were quantified by using two texture descriptors, namely, Square Root Pair Difference (SRPD) and Gi*. Then, a novel method, based on SRPD and Gi*, to extract building areas in urban areas from very high resolution SAR images is presented. The results showed that this method has the ability to differentiate buildings from the complicated features in urban areas, which can be employed for land mapping and provides support for relief operations.

Production management of winter wheat is more complicated than other crops since its growth period is covered all four seasons and growth environment is very complex with frozen injury, drought, insect or disease injury and others. In traditional irrigation and fertilizer management, agricultural technicians or farmers mainly make decision based on phenology, planting experience to carry out artificial fertilizer and irrigation management. For example, wheat needs more nitrogen fertilizer in jointing and booting stage by experience, then when the wheat grow to the two growth periods, the farmer will fertilize to the wheat whether it needs or not. We developed a spatial decision support system for optimizing irrigation and fertilizer measures based on WebGIS, which monitoring winter wheat growth and soil moisture content by combining a crop model, remote sensing data and wireless sensors data, then reasoning professional management schedule from expert knowledge warehouse. This system is developed by ArcIMS, IDL in server-side and JQuery, Google Maps API, ASP.NET in client-side. All computing tasks are run on server-side, such as computing 11 normal vegetable indexes (NDVI/ NDWI/ NDWI2/ NRI/ NSI/ WI/ G_SWIR/ G_SWIR2/ SPSI/ TVDI/ VSWI) and custom VI of remote sensing image by IDL; while real-time building map configuration file and generating thematic map by ArcIMS.

Recull de les intervencions i lliçons pronunciades en l’acte d'investidura com a doctor Honoris Causa de la Universitat de Lleida a Dong Yansheng, que va tenir lloc a Pequín, el dia 15 d'abril de 2014.

Along with the rapid development of urbanization since 1980s, immense changes of the land use/cover have been caused a series of problems of ecological environment, such as farmland decreasing, natural vegetation damage, construction land expansion, land desertification and salinization, and so on. The research on the changes and driving forces of spatial pattern of land use/cover by remote sensing is conducive to master the influences on ecosystem from natural factors and human factors and accelerate sustainable development of ecological environment. The LandSat MSS/TM/ETM+ images were used in the paper. Taken support vector machine (SVM) as classifier, the supervised classification was carried out to extract the spatial distribution of each land cover types in 1978, 1992, 2000 and 2010. By calculating the transition matrix among four result images, the changes of spatial patterns of land cover in Beijing in recent thirty years was analyzed from numeral and spatial dynamics. Result showed that the land use/cover in Beijing region had changed a great deal from 1978 to 2010. The farmland area and unused land area were decreasing with a range more than 40% in recent 32 years, while the urban area and forest area were increasing with a range more than 35%. Most of the farmland was transformed into urban land and forest, while the grassland was transformed into farmland. The input urban area was mainly originated from farmland, while the output was grassland. It indicated that the urbanization and afforestation were the two primary drivers of land use/cover change in Beijing region in recent thirty years.

It is significant to monitor crop waterlogging range timely and correctly for later field management, agricultural insurance and yield prediction. The change regularity of paddy injured growth was analyzed and the sensitive parameters of growth stress were screened. The model of identifying the paddy waterlogging range based on change vector analysis (CVA) was developed by using the HJ-1/2 CCD images around waterlogging. At last the accuracy of the developed model was evaluated by in-situ sample data. Results showed that the waterlogged paddy mainly scattered around the Huaihe River system. The spatial distribution pattern was in conformity with the occurrence tendency of paddy waterlogging provided by local agricultural department as a whole. By evaluating the accuracy of the model with in-situ samples, the overall accuracy of the model developed in the study reached 87.5%, while the Kappa coefficient reached 0.737. The change vector analysis model could identify the waterlogged paddy and normal paddy correctly and efficient in Huaihe River Basin.

In regional scale, satellite data was gained frequency nearly a day or more shorter, and these satellite data had already been wildly used for drought monitoring. Meanwhile, a variety of information systems of drought monitoring based on client/server architecture were developed and employed. However, these systems were too professional for non-professional workers to use. With the development of WebGIS technology, it was possible to realize online drought monitoring based on satellite data. In the northern of China, the main crop was winter wheat. The quality and yield of winter wheat were affected seriously due to drought. In this study, for the purpose of rapid monitoring winter wheat drought, a web system was developed according to the growth characteristics of winter wheat. First, the design concepts, general structure and function modules of drought monitoring system were introduced. In our system, experience model of monitoring drought using satellite data was embedded in online system to analysis the severity of winter wheat drought. Second, key technologies of system were elaborated. System environment under the Myeclipse platform was set up. The language in presentation layer was linked to that in logic layer by using middleware named blazeDS. BlazeDS software realized the interaction between the client and the server. Satellite imageries was processed by calling IDL program. Finally, an initial testing demonstrated our system can be operated in a simpler way to analysis drought information of winter wheat based on satellite data. It can be concluded that this system is widely useful for providing decision-making support information to agricultural departments in a real-time.

China southwest region has suffered from three years of severe drought in the dry season from 2010 to 2012, with devastating impacts on agricultural productions. Previous agricultural cropping patterns were adjusted to adapt to drought. How to find evidences of agricultural adaption to drought? Here, we showed agriculture adaptation to drought stress according to the changes of vegetation greenness, a proxy for agricultural drought conditions. Based on weather station observation from 1991 to April 2012, we concluded that the study area suffered from extreme drought in the dry reason of both 2010 and 2012. Notably, based on satellite monitoring of agricultural vegetation greenness in ten years, the results showed that drought intensity in 2010 and 2012 was almost equivalent (−66.85% in 2010 and −65.87% in 2012) and drought extension in 2012 was 14.52%, which was less than the half of 36.46% in 2010. Overall, the evidences of agricultural adaption to drought were obvious.

Drought is a main meteorological disaster leading to significant environmental, social and economic consequences due to its high frequency and large influence. Traditional methods of drought monitoring are to simplify drought into drought indices derived from weather station data. With the development of remote sensing, It is necessary to assess the potential of such indices derived from a specific sensor for drought monitoring in a particular region before we apply this remote-sensed measure in large area. This study assesses the SPIs in different time scales and their performance in identifying drought, as well as the potential of MODIS-derived spectral indices in drought monitoring in Hebei, an arid and semi-arid areas of Northern China. Reveal the relationship between different MODIS data and meteorological SPI in different time scales, so as to identify their feasibility for drought monitoring.

Sudden cooling during the crop growing phase seriously impacts crop growth. Crop vulnerability to low temperature stress is affected both by crop growing condition and the lowest environmental temperature. In this study taking winter wheat in Huang-Huai-Hai Plain of China as an example, vulnerability index to low temperature stress was assessed based on time series satellite data in nearly ten years. Growth sensitivity of wheat-frost was quantified by vegetation index change between tillering stage before winter and shooting stage in the next year. Exposure index of wheat-frost was defined as lowest land surface temperature during critical growth period. Cluster analysis of crop mean vulnerability index showed that high vulnerability of wheat-frost located in central and northern of Hebei Province in nearly 10 years. The result will help to prevent frost damage of winter wheat.

Drought and frost are two main natural disasters to winter wheat in China northern plain. Based on MODIS data in the last ten years, sensitive analysis of vegetation indices to these two disasters is presented in this paper. The result showed that EVI, NDIIb6 and NDIIb7 are suite for frost damage assessment. Although the winter wheat suffered serious drought in this region, the stress characteristics of winter wheat responded by both greenness change indices and water content change indices are not obvious.

Part 1: GIS, GPS, RS and Precision Farming; International audience; A yield estimation method by remote sensing was used to estimate the yield of winter wheat in Jiangsu province, China. The first step of this study was to extract the planting area of winter wheat from environmental satellite images and land -use map of Jiangsu province, meanwhile, correlation analyses were performed by using 8-day of composite Leaf Area Index (LAI) data from Moderate Resolution Imaging Spectroradiometer (MODIS) and statistical yield of corresponding counties. Secondly, the average LAI was calculated at the optimal growth period, and the statistical yields of wheat for all counties were collected, in which the former was chosen as the independent variable and the latter was the dependent variable, and the regression model was established. Finally, the accuracy and stability of the regression model were validated using the data of another year. The results indicated that the yield estimation model at provincial level was reliable, the Root Mean Square Error (RMSE) and the Mean Absolute Error (MAE) of the model was 12.1% and 9.7%, respectively. In addition, the yield estimation system of winter wheat in Jiangsu province was constructed and published based on ArcMap and ArcGIS Server.

The fusion method for the wide range resolution images will contribute to take the advantage of high time-resolution of MODIS data and high spatial-resolution of TM data, which will provide the time-series information matching the crop growth. The paper test the wavelet transform model from wavelet basis, decomposition level and fusion rule. By evaluating the quality of fusion images from several indexes, the paper analyzed the impact of fusion quality of MODIS and TM images from the parameter setting of wavelet transform. According to the comparison of many experiments, the study chose decomposition level 4, BIOR 6.8 of wavelet basis and high-replace-low of fusion rule. The study showed that the fusion method of wavelet transform could reserve the spectral feature of time-series information and enhance the spatial resolution from 250 meter to 30 meter. The time-series fusing images could be applied for crop monitoring.

In order to assessment hazard degree of urban earthquake disaster, a method of updating building information in spatial database is proposed based on high-resolution satellite images. With available high-precision geographic data in spatial database, the building information is extracted from high-resolution satellite images by object-based approach, and then used to update spatial database. According to the story number and volume of building, a preliminary evaluation of hazard degree for urban earthquake disaster is implemented in an experimental region.