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The problem which is concerned with filter-based neural control for switched uncertain nonlinear systems with incomplete measurement is studied in this paper. Filters are used to estimate unknown states, while neural networks approximate unknown functions. Data loss, saturation and other problems often occur during data transmission. An appropriate control law is designed by a backstepping method to solve this problem. Through using the average dwell time, it is proved that the switching system tends to be stable in a certain time. The analysis of probabilistic stability is also carried out to ensure that the system can achieve uniformly ultimately boundedness. Finally, the effectiveness of the previous design is proved by simulation. [ABSTRACT FROM AUTHOR]

Background: Typically developing (TD) siblings play a crucial role in promoting the health and well-being of adults with intellectual disabilities. Their involvement in the sibling relationship during adulthood may predict their likelihood of providing care to the sibling with intellectual disabilities (ID). However, different types of motivations (discretionary and obligatory) related to the contact frequency of TD siblings have not been fully explored. Little is known about how their negative experiences, such as affiliated stigma, influences relational motivations, which consequently affect contact frequency. This study examined these links in a Chinese context. Method: In total, 1,298 Chinese siblings were surveyed using questionnaires, and structural equation modelling was used to test the mediation effect. Results: Contact frequencies of TD siblings were significantly affected by discretionary motivation, obligatory motivation, and stigma experiences. The findings supported the mediating effect of obligatory motivation in the relationship between affiliated stigma and contact frequency. Conclusion: This study is among the first to examine whether the relational motivation of TD siblings predicts their contact frequency within their relationships with adult siblings with ID. We found that both types of relational motivations of TD siblings positively predicted contact behavior. [ABSTRACT FROM AUTHOR]

Objective: This cross-sectional study examined the levels of self-stigma, hope, and family functioning among Chinese people with mental illness (MI). We also investigated the mediating role of family functioning in the relationship between self-stigma and hope. Method: Three-hundred thirty participants with MI (Mage = 42.73, SD = 14.11, 52.09% female, 61.74% schizophrenia) were surveyed. Hayes' PROCESS macro analysis (Model 4) was performed to verify the mediating effect. Results: The analysis revealed that 43.1% of the respondents had a high level of self-stigma, 68.5% indicated a low/moderate level of hope, and 54% had moderate/severe impairment in family functioning. This supports the partial mediating effect of family functioning on the relationship between self-stigma and hope. Conclusions: The self-stigmatizing experiences of Chinese people with MI adversely impair normal family functioning and reduce hope, limiting recovery prospects. Relevant results highlight the influence of the family environment on the psychological mechanisms of PMI. Limitations and future research directions are addressed. [ABSTRACT FROM AUTHOR]

In order to study the response of fine root production (FRP), mortality (FRM) and turnover (FRT) to nitrogen (N) addition, we have conducted 12 years of continuous N addition experiments in the natural secondary forest in Northeast China. According to the local N deposition, three N treatments were set up. The response of FRP, FRM and FRT to N addition during the growing season was studied. The results showed that N addition would lead to phosphorus (P) limitation, and fine roots could increase the absorption of N and P by increasing their diameter. The increase in the diameter of fine roots led to a decrease in the FRT, and the soil layer also affected the FRT. Nitrogen addition increased the FRP and FRM in all soil layers. Nitrogen addition did not change the seasonal variation of FRP and FRM. The highest value of FRP occurred in May, and the lowest value of FRM occurred in August. Nitrogen addition increased the total number (TNLR) and surface area (TSALR) of live fine root in all soil layers. The TNLR and TSALR decreased with the deepening of soil layer. Collectively, fine roots may respond to environmental stress through self-regulation and changing growth strategies. [ABSTRACT FROM AUTHOR]

In the era of big data, there are numerous duplicate code snippets on the Internet, it is especially necessary to make use of them to build new software projects. In this paper, we present a toolkit (KG4Py) for generating a knowledge graph of Python files in GitHub repositories and conducting semantic search with the knowledge graph. In KG4Py, we remove all duplicate files in 317 K Python files and perform static code analyses of these files by using a concrete syntax tree (CST) to build a code knowledge graph of Python functions. We integrate a pre-trained model with an unsupervised model to generate a new model, and combine this new model with a code knowledge graph for the purpose of searching code snippets with natural language descriptions. The experimental results show that KG4Py achieves good performance in both the construction of the code knowledge graph and the semantic search of code snippets. [ABSTRACT FROM AUTHOR]

To better understand how contour-levee irrigation practice impacts water resources for formulating effective water management policies, it is important to obtain its application on large-scale data sets, e.g. state-wide. Automatic classification of contour levee croplands from high-resolution aerial images is of great potential given the success of deep neural networks and the availability of high-resolution remote sensing imagery. This paper proposes a gradient CNN model to classify fields with contour levees from remote sensing images. Our model produces high-quality segmentation masks that are refined with superpixel-based segmentation post-processing. Our method is evaluated using images by the National Agriculture Imagery Program (NAIP) for the counties in Arkansas. A comparison with the state-of-the-art methods demonstrates the improved performance of our proposed method. Our method demonstrates superior performance in the classification of challenging cases and achieves an overall 3.08% of accuracy improvement and 28.57% BER error reduction, compared to the second-best method. The p-value with respect to the second-best method is 0.005, which indicates great statistical significance. In addition, the results for data of different counties demonstrate the exceptional generalization ability of our method. [ABSTRACT FROM AUTHOR]

Rice agriculture is of great ecological, environmental, and socioeconomic importance in the Lower Mississippi Alluvial Valley, as its distribution and size heavily impact food production and a number of ecosystem services. Long-term rice mapping is challenging as a result of insufficient training data – both in spatial amount and in temporal coverage, the high cost of powerful geospatial data processing platforms, and incomplete image coverage during the critical window to capture the unique rice signals. Here, we developed a simple yet effective method for rice field extraction without heavy reliance on the complete profiles of Landsat time series or repeated training data. The core is a multiple-year training sample normalization that extends the samples obtained in one year for classification in another year. Pseudo-invariant objects and a set of linear regressions were used to predict what the given vegetation index values of training samples would be if they had been acquired under the same conditions in a different mapping year. The generated pseudo training samples were further utilized to classify the mapping image. We experimented with four years' Landsat Thematic Mapper and Operational Land Imager data and achieved comparable accuracies as the single-year classification. Because of its simplicity and low computational requirements, it can be efficiently implemented on cloud computing platforms, such as Google Earth Engine platform. This technique provides an affordable and effective solution to derive crop distribution information on a large-scale basis. [ABSTRACT FROM AUTHOR]

Objective: Weight gain is one of the most challenging issues in patients with schizophrenia treated with antipsychotics. Several meta-analyses have been conducted to review the efficacy of topiramate in reducing weight, however, several issues regarding the methodology had arisen of which make the results remain ambiguous. Methods: We conducted a meta-analysis of randomised controlled trials about the use of topiramate in patients with schizophrenia for weight reduction. Ten double-blinded randomised placebo-controlled trials and seven open-label randomised controlled trials included 905 patients. Results: Patients treated with topiramate experienced a greater reduction in body weight and BMI. Patients in countries of the lower overweight population showed more significant BMI reduction. Besides, studies from the Middle East and South Asia showed the greatest effect in body weight change, followed by East Asia, then Europe=America. Topiramate group was outperformed control group with significant psychopathology improvement. No difference between two groups regarding the overall side effects. Conclusions: Topiramate was significantly superior to control group in mitigating weight gain and psychopathology in antipsychotic-treated patients with schizophrenia. The effects of topiramate augmentation need further investigations in larger definitive studies using methodological rigor and thorough assessments. [ABSTRACT FROM AUTHOR]

The distribution of leafless and full-canopy trees in fall is essential in understanding the phenological and morphological characteristics of forests and those are critical baseline information for several scientific questions and management scenarios. The rapid progress of very high-resolution satellite-borne sensors provides a feasible solution to fast and accurately map tree coverage during the growing season. However, less attention has been paid to the leaf-off seasons. One biggest challenge with classification on fall imagery is the potential confusion among different land features, as evidenced by the no significant difference between bare land and leafless trees from t-test and transformed divergence (TD) analysis results. We proposed an integrative approach to classifying leafless and full-canopy trees on fall imagery of 0.46-m WorldView-2 (WV-2). We adopted a two-step classification approach by first removing the non-forest area from the WV-2 imagery with the mask layer generated from the publicly available summer imagery of 1-m National Agriculture Imagery Program imagery via object-based image analysis. Two classification methods, namely decision tree (DT) and nearest neighborhood (NN), were employed to classify full canopy and leafless trees in the masked WV-2 imagery. DT performed slightly better than NN regarding higher overall accuracy and fewer feature requirements. [ABSTRACT FROM AUTHOR]

Urban cellular automata (CA) models propagate and accumulate errors during the modeling process due to the model structure or stochastic processes involved. It is feasible to assimilate real-time observations into an urban CA model to reduce model uncertainties. However, the assimilation performance is sensitive to the spatio-temporal units in the assimilation algorithm, that is, spatial block size and window length (temporal interval). In this study, we coupled an assimilation model, an ensemble Kalman filter (EnKF) and a Logistic-CA model to simulate the urban dynamic in Beijing over a period of two decades. Our results indicate that the coupled EnKF-CA model outperforms the CA-alone counterpart by about 10% in terms of the figure of merit, which reflects the agreement of modeled pixels. We also find that the assimilation performance using a finer block (1 km) is better than that using a coarser block (5 km and 10 km) because of the better depiction of spatial heterogeneity using a finer block. Moreover, the improvement of intermediate outputs using the coupled EnKF-CA model is effective for a certain period (e.g. 5 years). This implies that a high-frequency assimilation may not significantly improve the model performance. The sensitivity analyses of spatio-temporal assimilation in the EnKF-CA model provide a better understanding of the assimilation mechanism that couples with land-use change models. [ABSTRACT FROM PUBLISHER]

In this paper, we introduced major challenges in mapping croplands, settlements, water and wetlands, and discussed challenges in the use of multi-temporal and multi-sensor data. We then summarized some of the on-going efforts in improving qualities of global land cover maps. Existing technologies provide sufficient data for better map making if extra efforts can be made instead of harmonizing and integrating various global land cover products. Developing and selecting better algorithms, including more input variables (new types of data or features) for classification, having representative training samples are among conventional measures generally believed effective in improving mapping accuracies at local scales. We pointed out that data were more important in improving mapping accuracies than algorithms. Finally, we proposed a new paradigm for global land cover mapping, which included a view of vegetation classes based on their types and form, canopy cover and height. The new paradigm suggests that a universally applicable training sample set is not only possible but also effective in improving land cover classification at the continental and global scales. To ensure an easy transition from traditional land cover mapping to the new paradigm, we recommended that an all-in-one data management and analysis system be constructed. [ABSTRACT FROM AUTHOR]

Global land cover data could provide continuously updated cropland acreage and distribution information, which is essential to a wide range of applications over large geographical regions. Cropland area estimates were evaluated in the conterminous USA from four recent global land cover products: MODIS land cover (MODISLC) at 500-m resolution in 2010, GlobCover at 300-m resolution in 2009, FROM-GLC and FROM-GLC-agg at 30-m resolution based on Landsat imagery circa 2010 against the US Department of Agriculture survey data. Ratio estimators derived from the 30-m resolution Cropland Data Layer were applied to MODIS and GlobCover land cover products, which greatly improved the estimation accuracy of MODISLC by enhancing the correlation and decreasing mean deviation (MDev) and RMSE, but were less effective on GlobCover product. We found that, in the USA, the CDL adjusted MODISLC was more suitable for applications that concern about the aggregated county cropland acreage, while FROM-GLC-agg gave the least deviation from the survey at the state level. Correlation between land cover map estimates and survey estimates is significant, but stronger at the state level than at the county level. In regions where most mismatches happen at the county level, MODIS tends to underestimate, whereas MERIS and Landsat images incline to overestimate. Those uncertainties should be taken into consideration in relevant applications. Excluding interannual and seasonal effects,R2of the FROM-GLC regression model increased from 0.1 to 0.4, and the slope is much closer to one. Our analysis shows that images acquired in growing season are most suitable for Landsat-based cropland mapping in the conterminous USA. [ABSTRACT FROM AUTHOR]

Since the launch of the first land-observation satellite (Landsat-1) in 1972, land-cover mapping has accumulated a wide range of knowledge in the peer-reviewed literature. However, this knowledge has never been comprehensively analysed for new discoveries. Here, we developed the first spatialized database of scientific literature in English about land-cover mapping. Using this database, we tried to identify the spatial temporal patterns and spatial hotspots of land-cover mapping research around the world. Among other findings, we observed (1) a significant mismatch between hotspot areas of land-cover mapping and areas that are either hard to map or rich in biodiversity; (2) mapping frequency is positively related to economic conditions; (3) there is no obvious temporal trend showing improvement in mapping accuracy; (4) images with more spectral bands or a combination of data types resulted in increased mapping accuracies; (5) accuracy differences due to algorithm differences are not as large as those due to various types of data used; and (6) the complexity of a classification system decreases its mapping accuracy. We recommend that one way to improve our understanding of the challenges, advances, and applications of previous land-cover mapping is for journals to require area-based information at the time of manuscript submission. In addition, building a standard protocol for systematic assessment of land-cover mapping efforts at the global scale through international collaboration is badly needed. [ABSTRACT FROM PUBLISHER]

We have produced the first 30 m resolution global land-cover maps using Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) data. We have classified over 6600 scenes of Landsat TM data after 2006, and over 2300 scenes of Landsat TM and ETM+ data before 2006, all selected from the green season. These images cover most of the world's land surface except Antarctica and Greenland. Most of these images came from the United States Geological Survey in level L1T (orthorectified). Four classifiers that were freely available were employed, including the conventional maximum likelihood classifier (MLC), J4.8 decision tree classifier, Random Forest (RF) classifier and support vector machine (SVM) classifier. A total of 91,433 training samples were collected by traversing each scene and finding the most representative and homogeneous samples. A total of 38,664 test samples were collected at preset, fixed locations based on a globally systematic unaligned sampling strategy. Two software tools, Global Analyst and Global Mapper developed by extending the functionality of Google Earth, were used in developing the training and test sample databases by referencing the Moderate Resolution Imaging Spectroradiometer enhanced vegetation index (MODIS EVI) time series for 2010 and high resolution images from Google Earth. A unique land-cover classification system was developed that can be crosswalked to the existing United Nations Food and Agriculture Organization (FAO) land-cover classification system as well as the International Geosphere-Biosphere Programme (IGBP) system. Using the four classification algorithms, we obtained the initial set of global land-cover maps. The SVM produced the highest overall classification accuracy (OCA) of 64.9% assessed with our test samples, with RF (59.8%), J4.8 (57.9%), and MLC (53.9%) ranked from the second to the fourth. We also estimated the OCAs using a subset of our test samples (8629) each of which represented a homogeneous area greater than 500 m × 500 m. Using this subset, we found the OCA for the SVM to be 71.5%. As a consistent source for estimating the coverage of global land-cover types in the world, estimation from the test samples shows that only 6.90% of the world is planted for agricultural production. The total area of cropland is 11.51% if unplanted croplands are included. The forests, grasslands, and shrublands cover 28.35%, 13.37%, and 11.49% of the world, respectively. The impervious surface covers only 0.66% of the world. Inland waterbodies, barren lands, and snow and ice cover 3.56%, 16.51%, and 12.81% of the world, respectively. [ABSTRACT FROM PUBLISHER]

The physical environment of myo- cardium, featuring excitation-con- traction coupling, constant and efficient provision of nutrient/oxygen and deli- cate integration of cardiomyocytes and supporting cell population (fibro- blasts, endothelial cells), is one of the most complex systems in human body. Numerous studies have demonstrated the significance of physical stimulation in cardiac cell physiology, including the maintenance of contractile function in cardiomyocytes,1 cell alignment and extracellular matrix secretion in fibro- blasts and endothelial cells.2,3 In effort to reconstruct the physical environment found in the cardiac niche for routine cell culture use, we have devised a biore- actor system to account for three major forms of physical stimuli, namely, cyclic stretch, electrical stimulation and fluid perfusion.4 [ABSTRACT FROM AUTHOR]

In order to evaluate whether mesenchymal stem cells (MSCs) from non-hematopoietic tissues are able to regulate megakaryocytopoiesis, we identified human MSCs from adult bone marrow (ABM), fetal pancreas (FPan) and umbilical cord (UC), and their abilities to support megakaryocyte (MK) differentiation from CD34+ hematopoietic progenitor cells (HPCs) were comparatively studied. First, MSCs were isolated from ABM, FPan and UC then their growth kinetics, molecular characterization and mesodermal differentiation capacity were determined. ABM-MSCs, FPan-MSCs and UC-MSCs were irradiated and cocultured with human umbilical cord blood (UCB) CD34+ cells, and the expansion efficiency of MK progenitor cells and MK formation were analysed and compared. Finally, SCF, IL-6 and GM-CSF expression by the three types of MSCs were also examined. Our results showed that FPan-MSCs and UC-MSCs shared most of the characteristic of ABM-MSCs, including morphology, immunophenotype, adipogenic and osteogenic differentiation potentials. Compared with ABM-MSCs, fetal MSCs had higher proliferative capacity. After 7 days’ coculture, the maximal production of CD34+/CD41a+ cells was obtained in a group of CD34+ HPCs + ABM-MSCs. Furthermore, this group produced more MK colonies than other groups ( p < 0.05). Surface antigen and ploidy analysis morphological observation demonstrated that a proportion of expanded cells in each group differentiated into mature MKs. ABM-MSCs, FPan-MSCs and UC-MSCs were revealed to express SCF, IL-6 and GM-CSF at mRNA level. We conclude that FPan-MSCs and UC-MSCs have the ability to promote megakaryocytopoiesis, while ABM-MSCs expand more MK progenitor cells from CD34+ HPCs than MSCs from non-hematopoietic tissues and CD34+ cells alone. [ABSTRACT FROM AUTHOR]

Google Earth uses aerial and satellite images from various sources as its background. It is designed to enable every person who owns a computer to easily 'fly' to aerial views of any location on the planet. However, just as with ordinary aerial or satellite images, there inevitably exist shadows in Google Earth images, making some ground objects obscured, even unidentifiable. In this paper, we describe a model we have developed for image shadow removal that uses radiative transfer theory in combination with prior knowledge to compensate for the lost information over shadow areas. We arbitrarily selected six images with severe shadows from Beijing, Shanghai, Hong Kong, Tokyo, New York and San Francisco, respectively, for algorithm testing. Our experimental results show that shadows in images can be considerably suppressed. [ABSTRACT FROM AUTHOR]

Wastewater from animal farms in China is threatening the quality and security of the local water environment. A traditional sequencing batch reactor (SBR) and a reformed SBR integrated with two-step feeding and low-intensity aeration at laboratory scale were investigated in this study for biological removal of nutrients and organic matter from swine wastewater. A low efficiency and poor stability were found under the traditional SBR, and the reduction of total nitrogen (TN), total phosphorus (TP) and biochemical oxygen demand (BOD5) reached 89.1, 86.0 and 93.9%, respectively. When the wastewater was treated with the reformed SBR under the running cycle of anaerobic/anoxic-anaerobic/anoxic process, the reductions in TN, TP, and BOD5 reached a maximum of 94.0, 99.3 and 99.9%, respectively. The curves of oxidation reduction potential (ORP) and nutrients over time during operation of the reformed SBR could reflect the activity of denitrifying phosphorus-accumulating organisms (DNPAOs). [ABSTRACT FROM AUTHOR]

Although the etiology underlying scar formation is not well understood, previous studies revealed that endothelial cells play a role in the pathogenesis of scar development. Recently, the authors developed a reliable technique to obtain endothelial cells from hypertrophic scars that involved separation of cells from the scar tissue matrix and isolation from other cell types. Using phase-contract and electron microscopy, the cells were observed to have a characteristic morphology consistent with cells of endothelial origin. The cells were further characterized as endothelial cells by assessment of endothelin (ET)-1 and intercellular adhesion molecule (ICAM) mRNA expression, and the presence of factor VIII antigen, CD34, CD31, and VE-cadherin. This isolation method provides a simple method for culturing endothelial cells from hypertrophic scar tissue and should prove useful for studying the role of endothelial cell involvement in scar formation. [ABSTRACT FROM AUTHOR]

Objective Until now, the epidemiology of functional dyspepsia (FD) and its social impact on Asians have been rarely studied. The aims of this study were to determine the prevalence, social impact, and health-seeking behaviors of FD in an apparently healthy Chinese population in Taiwan. Material and methods Based on the questionnaire provided by the Rome II working team, a survey was administered to a Taiwanese population receiving paid physical check-up (n=2865). Esophagoduodenoscopy was performed in each subject to exclude organic dyspepsia. Finally, diagnoses of functional gastrointestinal disorders were obtained by means of a computer-generated algorithm. Results The FD prevalences were 23.8% and 11.8% according to the Rome I and -II criteria, respectively. Nearly 60% of Rome I-defined FD subjects and 18.9% of Rome II-defined FD subjects had overlapping irritable bowel syndrome (IBS). Irrespective of any Rome definition, FD subjects had excessive physician visits, absenteeism, and sleep disturbances compared to dyspepsia-free controls (p<0.01). Moreover, over half of the Rome II FD subjects were “consulters” showing excessive physician visits, absenteeism, and sleep disturbances than “non-consulters”. The dysmotility-like subgroup (74.5%) comprised the majority of FD subjects and showed no differences to their ulcer-like counterparts in terms of major demographic data and social and health impacts. Conclusions FD is a common complaint in Taiwan and also bears an obvious social and medical burden to society. Over half of our FD subjects sought medical help, which may be due to the readily accessible medical care in Taiwan. The newly defined Rome II criteria diminish the chance of co-existence of FD and IBS. Further FD classification by the main symptoms appears of limited clinical usefulness. [ABSTRACT FROM AUTHOR]