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While urban growth management has shown varying degrees of success in curbing urban land expansion, their effects over time and across urban land uses remain largely unexplored. We used nationwide longitudinal data and difference-in-difference models to assess the effect of construction land quotas on changes in residential, industrial, commercial, public service, and aggregate land uses in 274 Chinese cities between 2010 and 2019. Results show that more stringent quotas were initially effective in containing urban land expansion but lost their effectiveness later. Over the entire period, however, the quotas had no significant effect. Such ineffective quota led to a higher percentage of residential land at the expense of industrial land, but unaffected commercial and public service land. Our findings highlight that these effects were driven by strong revenue incentives favoring profitable residential construction. This underscores the crucial importance of considering the roles various urban land uses play in local revenue and economic development when enforcing urban growth management.

Abstract Understanding the temporal dynamics of soil microbial biomass is crucial for assessing soil ecosystem functions and services, yet these dynamics are globally uncertain. Here, we compiled a data set of soil microbial biomass carbon (MBC) and nitrogen (MBN) from 1493 studies between 1988 and 2019 to elucidate their temporal trends and potential drivers. Results showed that global MBC and MBN significantly decreased by 0.033 Mg C ha−1 yr−1 and 0.007 Mg N ha−1 yr−1 at 0–30 cm soil depth, between 1988 and 2019, respectively, which might be primarily attributed to the warming of the climate, the increase in global precipitation, and reduction of soil organic carbon (SOC) stock. The rate of decline in MBC and MBN showed a non‐linear trend: following a decline from 1988 to 1999, it slowed down until 2014, likely due to the global warming hiatus. Afterward, the pace of decline increased again from 2015 to 2019. Boreal biomes experienced the largest decrease in soil microbial biomass with the reduction rate of MBC being 4.3 times higher than in temperate biomes, showing a higher sensitivity in boreal biomes to climate change. Grassland ecosystems also exhibited greater reductions, possibly driven by their degradation. These findings shed valuable insights on the long‐term dynamics of soil microbial biomass on a global scale over the last three decades. Furthermore, this study underscores the importance of preserving soil microbial biomass as a key strategy to mitigate the adverse effects of future climate change, thereby sustaining ecosystem health and resilience.

Objective The Gudui-Nanliang spring basin located in southern Shanxi Province is a complex karst water system with the coexistence of deep and shallow circulation, the transformation of cold and hot water, and multistage discharge. Due to long-term unreasonable exploitation and utilization, a series of geological environment problems related to karst groundwater have emerged in the spring basin. The present study aims to propose an ecological restoration and planning scheme for the spring basin by discussing in detail the status of karst groundwater-related environmental problems and their causes. Methods Based on a hydrogeological survey, this paper comprehensively employs a variety of methods, including comparative analysis of groundwater flow field, hydrogeochemical and isotopic analysis, and evaluation of karst water resources. Results The results show that due to the superimposed effects of climate change and human activities, Gudui Spring, Nanliang spring, and Haitou spring cut off the flow in 1999, 1992, and 2002, respectively, and the average decline rate of the regional groundwater level from 2013 to 2021 reaches 2.53 m/a. The results of hydrochemical and isotopic analysis indicate that the recharge to the karst groundwater of porous groundwater from unconsolidated deposits through leakage and surface water from Sanquan Reservoir through seepage cannot be ignored. The proportion of karst water samples worse than the water quality standard of class Ⅲ in the spring basin increased from 62.5% in 2014 to 81.25% in 2021. The range of 0.904 km2 of the spring source area can be subdivided into core protection zone, general protection zone and reservoir storage zone. Ecological protection and restoration planning should be carried out considering the differences between the three zones. Conclusion The results of the study can provide a basis for the comprehensive management of groundwater overexploitation areas in Shanxi Province and the ecological restoration and protection of Gudui spring basin.

Objective Karstic spring water is an important source of water supply for the karst areas of northern China. To rationally evaluate and scientifically exploit karstic water resources, it is important to identify the recharge, runoff and discharge conditions of spring water and to clearly depict the boundary of the spring area. Methods Targeting the issues of ambiguous border and unknown replenishment situations of the Gudui-Nanliang spring groups, this paper investigated and analysed the karst hydrogeological conditions of the spring area and the distribution characteristics of δD, δ18O and 87Sr/86Sr isotopes in the karstic water. The water-rock interactions and the hydraulic connection along the recharge-runoff path of karstic water were systematically examined by using isotope technique. Results The results show relatively large range of δ18O values in the karstic water. This is mainly attributed to the impacts of altitude effect, isotopic shift of oxygen in hot water, evaporation-induced enrichment and mixing of ancient sealed water. The distribution characteristics of δD, δ18O and 87Sr/86Sr in the karstic water provide strong evidence for the identification of the hydraulic connection of karstic groundwater. The formation of the Fenyangling geothermal field may be related to the water-rock interactions of the Mesozoic magmatic rocks that invaded the carbonate rocks. Also, the exploitation of karstic water in the north of the spring area will seize the karstic water resources in the spring area. Conclusion Overall, the investigation outcomes of karstic water isotopes in the Gudui-Nanliang spring area can provide a scientific basis for the management and protection of regional karstic water resources.

Rapid development of urbanization and intense human activities had a profound influence on the ecosystem service functions. As an integrated monetary index for the evaluation of final ecosystem services, the gross ecosystem product (GEP) is widely used in the quantification of ecosystem service value (ESV). This study initially assessed and analyzed the spatial distribution of the GEP at the county-level scale using multisource data spanning 2000, 2005, 2010, 2015, and 2020. Then, the spatial transfer characteristics of the GEP were measured. Finally, the study employed spatial panel econometric models and the geographically weighted regression (GWR) model to investigate the spatial effect of urbanization and ecological construction on the GEP. The results indicated that: (1) In 2020, the GEP in the Yangtze River Delta Region was RMB 15.24 trillion, and the GEP per unit area was RMB 42.58 million per square kilometer. It exhibited a cumulative decrease of RMB 298.72 billion from 2000 to 2020. (2) The spatial transfer efficiency of the GEP in urban agglomerations showed a clear decline trend. During the period of 2000–2020, over 96% of county-level units exhibited a decline with RMB 90,076,103.17/km2, indicating a consistent downward trend from the central regions towards the periphery. (3) Based on the decomposition effects of the spatial Durbin mode, urbanization and the ecological construction indicator showed spatial spillover effects on the GEP, but their impact mechanisms varied substantially. Among them, the urbanization rate (UR), population density (PD), and the proportion of impervious land (ILP) had the largest negative effect on the GEP, and a 1% rise in ILP locally resulted in a 0.044% decline in the local GEP and a 0.078% rise in the GEP of neighboring units. And the area of ecological land had a positive effect on the GEP of both local and neighboring areas. Those conclusions can offer evidence in favor of encouraging ecologically responsible building practices and sustainable growth in urban agglomerations.

Phenological changes caused by urbanization may provide evidence of how vegetation responds to global warming. However, the phenological characteristics of vegetation in metropolitan areas have been poorly studied, especially in terms of spatiotemporal variations. In this study, we explored the applicability of Local Climate Zones (LCZs) to investigate the spatiotemporal variations in urban vegetation phenology by linking MODIS-derived phenology metrics with LCZs in the Austin metropolitan area in Texas, USA. We extracted three vegetation phenology metrics from MODIS data between 2008 and 2018, including the start of growing season, end of growing season, and length of the growing season (i.e. SOS, EOS, and LOS, respectively). The results showed that during the study period, the EOS and SOS gradually advanced, while LOS showed no obvious change. Statistical analysis was conducted to examine the spatiotemporal variations of the phenology metrics among different LCZs and along “Urban-Rural Gradients” (URGs). There were 37.5%, 75.0%, and 74.3% pairs of LCZs, indicating statistically significant phenological differences in terms of SOS, EOS, and LOS in 2012, respectively. In contrast, most pairs of URGs showed almost no differences in phenological metrics, especially in EOS. Geographically, SOS showed a fluctuating change with an advancing tendency, whereas the EOS decreased very slowly with distance from the city center (i.e. along the URGs). LCZs can be used to help identify distinctive phenology metrics with statistically significant differences, especially in EOS and LOS. Compared to URGs, LCZs offer a unique analytical framework for studying urban ecosystem patterns, functions, and dynamics. Lastly, LCZs can enable the identification of sensitive areas for ecological protection in support of sustainable urban development and environmental stewardship.

The change of the impervious surface area (ISA) is an important feature of urban spatial expansion. Understanding the spatial and temporal change characteristics of urban impervious surfaces and their influencing factors is of great significance to the planning, management, and urbanization development of cities. This paper adopts a global artificial impervious surface dataset, with a resolution of 30 m, calculates and processes the data based on the ArcGIS platform, adopts the MK trend test method, introduces the dynamic degree, qualitatively and quantitatively analyses the changing characteristics of the ISA in the Central Plains Urban Agglomeration (CPUA), and analyzes the influencing factors of ISA changes using GeoDetector. The results show that the ISA dynamic degree was significantly enhanced from 2000 to 2018, which increased 1.86 times, indicating the accelerated outward expansion of the CPUA and the rapid level of urban development during that period. The explanatory power of the greenery coverage area on the change of the ISA in the CPUA during 2000–2018 was the strongest; the same factor has different explanatory powers for the ISA in different periods. The influencing factors have an enhanced relationship between two and two, including two-factor enhancement and nonlinear enhancement, in 2000–2009, during which the interaction level of the greenery coverage area and the GDP per capita was strong, while from 2009 to 2018, the interaction between transportation and other factors was significantly strong.

Urban heat islands (UHIs) are a key topic in urban climate studies. However, systematic criteria for UHI comparisons were lacking prior to 2012, when the concept of Local Climate Zones (LCZs) was introduced. By relating remotely sensed land surface temperature (LST) to LCZs, we explored the applicability of LCZs in surface urban heat island (SUHI) investigations and compared the LST variation within and among LCZs for the Austin, San Antonio, and Dallas-Fort Worth metropolitan areas in Texas, United States. Landsat 8 images from one summer and one winter day in 2015 were used to obtain LSTs to measure and model SUHIs. LCZs that were characterized by different land covers had the greatest LST variations, and LCZs that were further characterized by various urban morphological properties (including building density and height of roughness) also showed significant LST differences. Moreover, LCZ 9 (sparsely built), LCZ 10 (heavy industry), LCZ D (low plants), LCZ E (bare rock or paved), and LCZ F (bare soil or sand) tended to contribute to contradictory heating/cooling effects in different metropolitan areas, primarily due to the spatial arrangement and geographic locations of LCZs. The close association between LCZs and LST demonstrates that LCZs are valuable for comparative analysis of the SUHI phenomenon between different cities and can be helpful for examination of the evolution of SUHIs over time. Our findings further suggest that understanding the spatial distribution of LCZs can benefit the development of mitigation strategies for SUHIs.

Accurate urban boundary data can directly reflect the expansion of urban space, help us accurately grasp the scale and form of urban space, and play a vital role in urban land development and policy-making. However, the lack of reliable multiscale and high-precision urban boundary data products and relevant training datasets has become one of the major factors hindering their application. The purpose of this study is to combine Sentinel-2 remote-sensing images and supplementary geographic data to generate a reliable high-precision urban boundary dataset for Henan Province (called HNUB2018). First, this study puts forward a clear definition of “urban boundary”. Using this concept as its basis, it proposes a set of operable urban boundary delimitation rules and technical processes. Then, based on Sentinel-2 remote-sensing images and supplementary geographic data, the urban boundaries of Henan Province are delimited by a visual interpretation method. Finally, the applicability of the dataset is verified by using a classical semantic segmentation deep learning model. The results show that (1) HNUB2018 has clear and rich detailed features as well as a detailed spatial structure of urban boundaries. The overall accuracy of HNUB2018 is 92.82% and the kappa coefficient reaches 0.8553, which is better than GUB (Henan) in overall accuracy. (2) HNUB2018 is well suited for deep learning, with excellent reliability and scientific validity. The research results of this paper can provide data support for studies of urban sprawl monitoring and territorial spatial planning, and will support the development of reliable datasets for fields such as intelligent mapping of urban boundaries, showing prospects and possibilities for wide application in urban research.

This paper estimates global logistic regression and logistic geographically weighted regression (GWR) models of urban growth in the adjacent border cities of Laredo, Texas in the United States and Nuevo Laredo, Tamaulipas in Mexico, for two time periods from 1985 to 2014. Historical land use and land cover patterns were monitored through Landsat imagery from the United States Geological Survey to identify instances of urban growth through land type change. Data on socioeconomic variables related to urban growth were collected from various sources and used as independent variables. In both time periods, the logistic GWR was proven to be a complementary model for the global logistic regression to explore the urban growth effect. In addition, GWR outperformed the global logistic regression model with respect to goodness of fit. These results suggest that local models are complementary to global models to empirically analyze the determinants of urban growth in study areas that contain political borders, presumably because the relationships between socioeconomic factors and urban growth are characterized by spatial heterogeneity in such areas. The spatial variable of the relationship between urban growth and the neighborhood interactions and proximity effect present the idea of complexity and interconnections between the land use change and associated factors.

This study focuses on the potential impacts of large-scale land use and land cover changes (LUCC) on surface temperature from a global perspective. As important types of LUCC, urbanization, deforestation, cultivated land reclamation, and grassland degradation have effects on the climate, the potential changes of the surface temperature caused by these four types of large-scale LUCC from 2010 to 2050 are downscaled, and this issue analyzed worldwide along with Representative Concentration Pathways (RCPs) of the Intergovernmental Panel on Climate Change (IPCC). The first case study presents some evidence of the effects of future urbanization on surface temperature in the Northeast megalopolis of the United States of America (USA). In order to understand the potential climatological variability caused by future forest deforestation and vulnerability, we chose Brazilian Amazon region as the second case study. The third selected region in India as a typical region of cultivated land reclamation where the possible climatic impacts are explored. In the fourth case study, we simulate the surface temperature changes caused by future grassland degradation in Mongolia. Results show that the temperature in built-up area would increase obviously throughout the four land types. In addition, the effects of all four large-scale LUCC on monthly average temperature change would vary from month to month with obviously spatial heterogeneity.

This study investigated how underlying biophysical attributes affect the characterization of the Surface Urban Heat Island (SUHI) phenomenon using (and comparing) two statistical techniques: global regression and geographically weighted regression (GWR). Land surface temperature (LST) was calculated from Landsat 8 imagery for 20 July 2015 for the metropolitan areas of Austin and San Antonio, Texas. We sought to examine SUHI by relating LST to Lidar-derived terrain factors, land cover composition, and landscape pattern metrics developed using the National Land Cover Database (NLCD) 2011. The results indicate that (1) land cover composition is closely related to the SUHI effect for both metropolitan areas, as indicated by the global regression coefficients of building fraction and NDVI, with values of 0.29 and −0.74 for Austin, and 0.19 and −0.38 for San Antonio, respectively. The terrain morphology was also an indicator of the SUHI phenomenon, implied by the elevation (0.20 for Austin and 0.09 for San Antonio) and northness (0.20 for Austin and 0.09 for San Antonio); (2) the SUHI phenomenon of Austin on 20 July 2015 was affected by the spatial pattern of the land use and land cover (LULC), which was not detected for San Antonio; and (3) with a local determination coefficient higher than 0.8, GWR had higher explanatory power of the underlying factors compared to global regression. By accommodating spatial non-stationarity and allowing the model parameters to vary in space, GWR illustrated the spatial heterogeneity of the relationships between different land surface properties and the LST. The GWR analysis of SUHI phenomenon can provide unique information for site-specific land planning and policy implementation for SUHI mitigation.

In ecologically fragile areas with arid climate, such as the Heihe River Basin in northwestern China, sustainable social and economic development depends largely on the availability and sustainable uses of water resource. However, there is more and more serious water resource shortage and decrease of water productivity in Heihe River Basin under the influence of climate change and human activities. This paper attempts to identify the severe water scarcity under climate change and presents possible solutions for sustainable development in Heihe River Basin. Three problems that intervened land use changes, water resource, the relevant policies and institutions in Heihe River basin were identified, including (1) water scarcity along with serious contradiction between water supply and demand, (2) irrational water consumption structure along with low efficiency, and (3) deficient systems and institutions of water resource management along with unreasonable water allocation scheme. In this sense, we focused on reviewing the state of knowledge, institutions, and successful practices to cope with water scarcity at a regional extent. Possible solutions for dealing with water scarcity are explored and presented from three perspectives: (1) scientific researches needed by scientists, (2) management and institution formulation needed by governments, and (3) water resource optimal allocation by the manager at all administrative levels.

There have been tremendous changes in the global land use pattern in the past 50 years, which has directly or indirectly exerted significant influence on the global climate change. Quantitative analysis for the impacts of land use and land cover changes (LUCC) on surface climate is one of the core scientific issues to quantitatively analyze the impacts of LUCC on the climate so as to scientifically understand the influence of human activities on the climate change. This paper comprehensively analyzed the primary scientific issues about the impacts of LUCC on the regional climate and reviewed the progress in relevant researches. Firstly, it introduced the influence mechanism of LUCC on the regional climate and reviewed the progress in the researches on the biogeophysical process and biogeochemical process. Then the model simulation of effects of LUCC on the regional climate was introduced, and the development from the global climate model to the regional climate model and the integration of the improved land surface model and the regional climate model were reviewed in detail. Finally, this paper discussed the application of the regional climate models in the development and management of agricultural land and urban land.

Yunnan province is the core region of the drought in the Southwest China, which makes the region become the hot spot in the meteorological research. However, among the various influencing factors of the drought in Yunnan province, the influence of the land use/cover change (LUCC) on the drought has not been quantitatively analyzed. The LUCC in recent decades was first quantitatively analyzed in this study. Given the fact that severe drought in Yunnan province is mainly due to much-less-than-normal precipitation and much-warmer-than-normal surface temperature, this study focused on the future spatiotemporal heterogeneity of the temperature and precipitation, which have great impacts on the drought. Finally, the influencing factors of drought in Yunnan province were simulated with the Weather Research and Forecasting (WRF) model, and the risk of drought was spatially analyzed with the meteorological drought composite index. The results indicate that the large-area forest plays a more important role in alleviating the risk of drought than other vegetation types do. Besides, the changes of the landscape structure resulting from the urban expansion play a significant role in intensifying the risk of drought.

The climate impacts of future urbanization in the Pearl River Delta (PRD) region in China were simulated with the Dynamics of Land Systems (DLS) model and the Weather Research and Forecasting (WRF) model in this study. The land use and land cover data in 2000 and 2020 were simulated with the DLS model based on the regional development planning. Then the spatial and temporal changes of surface air temperature, ground heat flux, and regional precipitation in 2020 were quantified and analyzed through comparing simulation results by WRF. Results show that the built-up land will become the dominant land use type in the PRD in 2020. Besides, the near-surface air temperature shows an increasing trend on the whole region in both summer and winter, but with some seasonal variation. The urban temperature rise is more apparent in summer than it is in winter. In addition, there is some difference between the spatial pattern of precipitation in summer and winter in 2020; the spatial variation of precipitation is a bit greater in summer than it is in winter. Results can provide significant reference for the land use management to alleviate the climate change.

The design and implementation of teachers' classroom teaching strategies is the key to the success of second language classroom teaching. In order to improve the quality of second-language classroom teaching in universities and enhance the interactivity in the teaching process, the application of virtual reality technology in second-language classroom teaching in universities is studied. Firstly, an integrated ware platform is designed for second language classroom teaching in universities, which consists of an integrated ware library and a database. Then virtual reality technology is used to design an integrated ware library within the platform and collect information such as various teaching media resources designed in the classroom teaching content into the integrated ware library; Utilize 3DS Max software in virtual reality technology to construct three-dimensional models of teaching scenes and entities; Choose to use linear difference method to render 3D model colors; From a visual perspective, enhance the realism of the rendered model through image enhancement technology and color contrast enhancement technology. According to the functions of the physical object, various interactive events are added to the created teaching scene and the three-dimensional model of the entity and stored in the integrable ware library to achieve panoramic roaming of the second language classroom teaching scene in universities. The experimental results show that the teaching platform designed by this method can accurately construct three-dimensional models of teaching scenes and objects with good visual effects, providing users with a more realistic sensory experience and effectively improving students' mastery of teaching content. [ABSTRACT FROM AUTHOR]

Background: The incidence of colorectal cancer (CRC) is on the rise. Furthermore, late-stage diagnoses and limited efficacious treatment options make CRC a complex clinical challenge. Therefore, a new therapeutic regimen with a completely novel therapeutic mechanism is necessary for CRC. In the present study, the therapeutic efficacy of oncolytic herpes simplex virus type 2 (oHSV2) in CRC was assessed in vitro and in vivo. oHSV2 is an oncolytic agent derived from herpes simplex virus type 2 that encodes granulocyte-macrophage colony-stimulating factor. Materials and methods: We investigated the cytopathic effects of oHSV2 in CRC cell lines using the MTT assay. Then, cell cycle progression and apoptosis of oHSV2 were examined by flow cytometry. We generated a model of CRC with mouse CRC cell CT26 in BALB/c mice. The antitumor effects and adaptive immune response of oHSV2 were assessed in tumor-bearing mice. The therapeutic efficacy of oHSV2 was compared with the traditional chemotherapeutic agent, 5-fluorouracil. Results: The in vitro data showed that oHSV2 infected the CRC cell lines successfully and that the tumor cells formed a significant number of syncytiae postinfection. The oHSV2 killed cancer cells independent of the cell cycle and mainly caused tumor cells necrosis. The in vivo results showed that oHSV2 significantly inhibited tumor growth and prolonged survival of tumor-bearing mice without weight loss. With virus replication, oHSV2 not only resulted in a reduction of myeloid-derived suppressor cells and regulatory T cells in the spleen, but also increased the number of mature dendritic cells in tumor-draining lymph nodes and the effective CD4+T and CD8+T-cells in the tumor microenvironment. Conclusion: Our study provides the first evidence that oHSV2 induces cell death in CRC in vitro and in vivo. These findings indicate that oHSV2 is an effective therapeutic cancer candidate that causes an oncolytic effect and recruits adaptive immune responses for an enhanced therapeutic impact, thus providing a potential therapeutic tool for treatment of CRC. [ABSTRACT FROM AUTHOR]

Ecological base flow is a basic requirement of water flow for a healthy river ecosystem. But in Weihe River the ecological flow is not guaranteed because of the water shortage, high sediment concentration and considerable agricultural water use along the river. In this study, Baojixia under-tableland irrigation area was selected as a representative area to which a mathematical model of one-dimensional steady water non-uniform sediment regulation was applied, to analyse the impact of channel desilting on guaranteeing the ecological base flow of Weihe River. The results indicated that scouring and silting of the channel was significantly correlated with the channel water capacity and sediment content in water flows. In addition, channel desilting contributed to 55.9x104m3 and 79.2x104m3 water saving in the irrigation area in January and December which belonged to the dry season. Their contribution rates to basic flow were 3.5% and 4.9%, respectively. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the effectiveness and safety of rivaroxaban for preventing venous thromboembolism (VTE) after lumbar spine surgery. Methods: In this randomized, controlled study, 665 patients who underwent lumbar surgery were randomly assigned to receive either rivaroxaban or parnaparin. Rivaroxaban and parnaparin were used for preventing postoperative venous thrombosis. The occurrence of postoperative efficacy endpoint events (venous thrombosis) and safety endpoint events (hemorrhage) was compared for each group. Results: Efficacy endpoint results: in the rivaroxaban group, there were 6 thrombotic events (1.7 %), 2 cases with severe VTE (0.6 %), and 3 cases with symptomatic VTE (0.9 %). In the parnaparin group, there were 10 thrombotic events (3.1 %), 4 cases with severe VTE (1.2 %), and 6 cases with symptomatic VTE (1.9 %). Safety endpoint results: in the rivaroxaban group, there were 21 cases with bleeding events (6.2 %), 2 cases with severe bleeding (0.6 %), and 19 cases with non-severe bleeding (5.6 %). In the parnaparin group, there were 21 bleeding events (6.2 %), 1 case with severe bleeding (0.3 %), and 16 cases with non-severe bleeding (4.9 %). The incidences of thromboembolic events, including severe and symptomatic VTE, were not significantly different between the two groups (P > 0.05). Bleeding event rates, including severe and non-severe bleeding, were also not significantly different. Conclusions: Rivaroxaban proved to be equally effective as parnaparin for anticoagulation therapy, with both drugs exhibiting a similar prevention effect against postoperative VTE after lumbar spine surgery, without increasing the risk of postoperative bleeding. [ABSTRACT FROM AUTHOR]

English becomes an important tool of academic research and international communication with the rapid development of global economy. Producing a piece of EAP writing with completeness, clarity and coherence has become a pursuit of both college students and academic staff. The coherence and completeness of EAP writing is realized mainly by lexical cohesion. However, it has long been ignored by Chinese EFL learners and teachers. Using the corpora of BAWE and EAP writing by British and Chinese learners, this research compares and contrasts the indices of lexical cohesion generated by computational linguistics tool, Coh-Metrix, across different levels and between English native speakers and Chinese EFL learners. It is found that both native speakers and Chinese EFL learners tends to use less simple repetition and more complicated cohesion with the improving of English language proficiency while the average frequency of lexical cohesion employed by Chinese EFL learners is less than native speakers. Therefore lexical cohesion teaching and learning should be given more consideration for successful EAP writing for Chinese EFL learners. [ABSTRACT FROM AUTHOR]

The terraced field widely distributed in Loess Plateau where serious soil and water loss happens, has a significant influence on watershed hydrological environment. At present, for the deficiency of watershed scale terraced fields hydrological environment impact assessment model and lacking of measured data, the terraced fields environmental impact assessment has attracted many attentions of the researchers. This paper adopts the hydrologic analogy combined with a scale physical model method, to infer the runoff and sediments in data-scarce area. Using the embedded terraced module SWAT model to assessment of terraced fields environmental impact, the results show that was a new way to conjecture the hydrologic data in data-scarce area. And the terraced field module can meet the accuracy requirement, the NS sufficient were both above 0.5 in calibration and verifying period. The soil erosion modulus of terraced fields contained in and removed from the watershed, was respectively 5.3% and 16.2% greater than the real. This indicates that the embedded terraced module SWAT model could be used in terraced fields environmental impact assessment in Loess Plateau small watershed. [ABSTRACT FROM AUTHOR]

Bilingual Education of Higher Education Institution in China (BEHIC) has been developed quickly in the last 10 years. However the lack of systematic theoretical and practical research hinders the development of BEHIC. In order to maintain multicultural feature in economy and politics, the strategies of developing BEHIC are to be studied in the research. [ABSTRACT FROM AUTHOR]

The data on polarization of the immune system towards T helper 1 (Th1) or T helper 2 (Th2) cells in immune thrombocytopenic purpura (ITP) are limited and contradictory. Th17 characterized by the production of Interleukin 17 (IL-17) has been shown to play a crucial part in the induction of autoimmune diseases. To further investigate the role of Th cytokines in the pathogenesis of ITP, we measured the plasma concentration of three Th17-associated cytokines [IL-17, transforming growth factor-ß (TGF-ß), IL-6] and Th1 cytokine interferon-γ (IFN-γ) in ITP patients, and evaluated their clinical relevance. The concentration of IL-17, TGF-ß, IL-6, and IFN-γ in plasma specimens from 29 adults with chronic ITP and 38 controls was analyzed by enzyme-linked immunosorbent assay method. No significant differences of Th17 cytokines (IL-17, TGF-ß, and IL-6) and Th1 cytokine (IFN-γ) concentration were observed between patients with active ITP and the control group. And the IFN-γ/IL-17 ratio representing Th1/Th17 cytokine profile was not significantly different between ITP patients and control, either. However, significantly positive correlation between IL-6 and IFN-γ in ITP patients was observed ( r = 0.48, P = 0.01). Among the ITP patients, Plasma IL-17 levels in male were marginally higher than those in female, while similar for TGF-ß, IL-6 or IFN-γ. There was a significantly positive correlation between age and IL-6 concentration in ITP patients ( r = 0.56, P = 0.0002), while no statistical significance between age and the other three cytokines. No significant correlation between cytokine concentrations and platelets or megakaryocytes number was found in ITP patients. In summary, ITP may not be associated with changes of plasma Th17 and Th1 cytokine concentrations relative to control population. [ABSTRACT FROM AUTHOR]

To investigate the effect and mechanism of the CD8+ T cells in bone marrow on autologous megakaryocytopoiesis in idiopathic thrombocytopenic purpura (ITP) patients, we prepared bone marrow mononuclear cells (MNCs) from 15 chronic ITP patients and 13 controls. MNCs were cultured in vitro directly (MNC group) or after depleting CD8+ T cells (CD8+ T-dep group) or adding purified autologous CD8+ T cells to CD8+ T-dep MNCs (Coculture group) or adding dexamethasone to the coculture (DEX group) all in semi-solid and liquid culture systems. The quantity and quality of megakaryocytes were measured. The megakaryocyte count was increased in the presence of autologous CD8+ T cells of patients with chronic ITP, while platelet production was reduced. In addition, lower percentages of polyploidy and apoptotic megakaryocytes, and higher levels of soluble Fas (sFas) in supernatant were observed. Dexamethasone successfully corrected this effect of CD8+ T cells on autologous megakaryocytopoiesis. These studies provide evidence that activated CD8+ T cells in bone marrow of patients with chronic ITP might suppress megakaryocyte apoptosis, leading to impaired platelet production. Megakaryocyte apoptosis would be a novel target for the management of ITP. [ABSTRACT FROM AUTHOR]

Chiral N,N′-dialkyl-1,2-cyclohexanediamine derivatives are developed and the products are utilized in combination with Cu(OAc)2 and iPr2NEt as catalysts for the asymmetric Henry reaction. [ABSTRACT FROM AUTHOR]