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Background: Thoracic aortic aneurysm and dissection (TAAD) is a life‐threatening pathology that remains a challenge worldwide. Up to 40% of TAAD cases are hereditary with complex heterogeneous genetic backgrounds. The purposes of this study were to determine the diagnostic rate of patients with TAAD, investigate the molecular pathologic spectrum of TAAD by next‐generation sequencing (NGS), and explore the future preclinical prospects of genetic diagnosis in patients at high ‐risk of study. Methods: NGS was used to screen 15 genes associated with genetic TAAD in 212 patients from northwestern China. Clinical data of patients were gathered by electrocardiography, transthoracic echocardiography, and computed tomography. Results: Of the 212 patients, 67 (31.60%) tested positive for a (likely) pathogenic variant, 42 (19.81%) had a variant of uncertain significance (VUS), and 103 (48.58%) had no variant (likely benign/benign/negative). A total of 135 reportable variants were detected in our test, among which 77 (57.04%) are first reported in this paper. A genotype–phenotype correlation of FBN1 was assessed, and the data showed that the patients with truncating and splicing mutations are more prone to developing severe aortic dissection than those with missense mutations, especially frameshift mutations (82.76% vs. 42.86%). In this study, 43 (20.28%) patients had a family history of sudden death or TAAD, whereas 132 (62.26%) did not (the remaining 37 were not available), and the positive rate of genetic testing was higher in TAAD patients with family history than in those without (76.74% vs. 18.94%). Conclusion: Our study concludes that genetic variation is an important consideration in the risk stratification of individualized prediction and disease diagnosis. [ABSTRACT FROM AUTHOR]

The article presents the authors' opinions on the publication of science and technology research by Chinese authors in the English language in American and British scholarly journals. The authors address the outflow of scientific research from Chinese scientists and argue that the flow should be stemmed so that Chinese journals could achieve a higher standing in the field of scholarly research. Topics include academic evaluation methods and internationalization.

This paper analyses the relationship between community attributes and the subway home-price capitalization effect, asking whether the magnitude of the subway proximity premium is affected by neighbourhood economic status and location. Using longitudinal data from Beijing, the paper estimates that decreasing a community's distance to a subway station by 10 per cent increases the housing price per square metre by 0.2 per cent ~ 0.9 per cent. The paper also shows that, subway capitalization effect is around 0.1 per cent ~ 0.2 per cent lower for communities that have higher quality and charge a 1 Yuan higher property management fee. Moreover, the analysis also reveals that the subway capitalization will decrease by around 0.08 per cent as a community's distance to the central business district (CBD) increases by 1 km. [ABSTRACT FROM AUTHOR]

Cone‐producing gymnosperms are important elements of the Mesozoic floras. Studying their cone organizations can potentially help us understand the evolutionary trends of seed plants through time and the origin of angiosperms. In this paper, we present a new and an undetermined species of Ixostrobus Raciborski, a fossil genus representing male cones of the Czekanowskiales from the Middle Jurassic Daohugou locality in Inner Mongolia, China. The holotype specimen of the new species was studied using the neutron tomography (NT) technique. The cone shows higher neutron attenuation than the surrounding matrix. To detect the different organic compounds, a volume rendering of tomographic reconstruction with false colour spectrum of relative neutron attenuation is presented. The highest concentration of organic material is in the axis and some parts of the sacs, the rest of the cone has lower concentration, and the surrounding matrix has the lowest concentration. It seems that the remnant organic materials are regularly differentiated in different parts of the cone probably because of the preservation and different taphonomic process of different type of cells. In addition to revealing more detailed morphological features of the cone by NT reconstruction, the application of NT is potentially important for detecting remnant organic materials preserved in fossil plants. [ABSTRACT FROM AUTHOR]

The Central Asian Orogenic Belt (CAOB) is one of the largest accretionary orogenic collages in the world with prominent juvenile crust addition, where the southernmost margin of the CAOB located is one hot topic in the international studies. The Dunhuang Block located to the south of the Beishan Orogen is a key position for outlining the tectonic framework of the south margin of the CAOB. However, at present, the tectonic attribution of the Dunhuang Block is still controversial. In this paper, we focus on the origins and protoliths of the meta‐mafic rocks from the Hongliuxia complex in the southern Dunhuang Block for determining the tectonic attribution of the Dunhuang Block. In the field, the meta‐mafic rocks are mainly exposed as tectonic blocks within the metasedimentary rocks displaying the "block‐in‐matrix" fabrics or as tectonic slices juxtaposed by faults. Geochemically, the meta‐mafic rocks could be divided into three groups based on the rare earth elements (REE) and trace elements: the group 1 samples are depleted in the LREE relative to HREE and show flat HREE patterns, similar to the mid‐oceanic ridge basalt; the group 2 samples show flat REE patterns without obvious differentiation between the LREE and HREE, like the oceanic plateau basalt; the group 3 samples are enriched in LREE relative to LREE, and have negative Nb, Ta, and Ti anomalies, similar to the island arc basalt. Conclusively, the protoliths of the meta‐mafic rocks dominantly belong to the oceanic plate components. They were metamorphosed during Early Silurian to Middle Devonian in different depths of the subduction zone documented in previous studies. So, we suggest the Hongliuxia complex is an exhumed Palaeozoic subduction–accretion complex (SAC) formed during the oceanic plate subduction. This result confirms the Palaeozoic subduction event occurred in the Dunhuang region and indicates that the Dunhuang Block is a Palaeozoic Orogen rather than a part of Precambrian continent block. Considering the regional geology context, we speculate the Dunhuang Orogen belongs to the southernmost margin of the CAOB. [ABSTRACT FROM AUTHOR]

The terrestrial sequence stratigraphy in proximal terrestrial environments is different from its counterpart in distal terrestrial and marine environments. The Southern Junggar Basin in NW China has preserved well‐exposed proximal terrestrial outcrops and its Jurassic–Cretaceous sequence boundary remains contentious. The goal of this paper is to (a) establish a model of allogenic‐controlling mechanisms of a proximal terrestrial sequence, (b) investigate the Jurassic–Cretaceous sequence boundary, (c) the Jurassic climate, and (d) tectonic movements in Central Asia. The sequence stratigraphic framework was established assisted by the determination of the accommodation space/sediment supply (A/S) ratio, including two second‐order sequences (SS) and six third‐order sequences (SQ) in the Jurassic, as well as a second‐order sequence in the Cretaceous. SS1 was mainly controlled by a warm and humid climate and lake level fluctuations in a weak extensional tectonic setting; SS2 was mainly controlled by an arid climate and compressional tectonic movements; SS3 was mainly controlled by a semi‐humid climate and lake transgression in a stable tectonic setting. Additionally, the Jurassic–Cretaceous sequence boundary was distinguished within the Kalazha Formation based on its sedimentary characteristics, sedimentary evolution, and different allogenic controls. It is concluded that the proximal terrestrial sequences exhibit rapid sedimentary facies change, thick coarse‐grained sediments, and multiple provenances. Climate, tectonic movements, and lake level fluctuation dominate in different stages of basin evolution. Moreover, the sediment supply is more emphasized, and the accommodation space/sediment supply ratio, which corresponds to different channel geometry types, plays a critical role in identifying system tracts and sequence stratigraphic surfaces. [ABSTRACT FROM AUTHOR]

This paper considers the pattens of international collaboration by analysing publications on COVID‐19 published in the first 6 months of the pandemic. The data set comprised articles on COVID‐19 indexed in the Web of Science Core Collection (WoS CC) downloaded four times between 1 April 2020 and 1 June 2020. The analysis of 5,827 documents revealed that 128 countries, 23,127 authors, and 6,349 institutes published on the pandemic. The data reveal that the three main publishing countries were the USA, China, and England with Italy closely following. Although publication was widely spread, most of the institutions with the highest volume of output were in China. Network analysis showed growth in international cooperation with an average degree of country/region cooperation rising to 23.06 by 1 June. There was also a clear core‐periphery structure to international collaboration. Institutional collaboration was shown to be highly regionalized. The data reveal a high and growing incidence of international collaboration on the pandemic. [ABSTRACT FROM AUTHOR]

The marginal area of a sedimentary basin is closer to the provenance, so the sand body is generally more developed. For the Western Margin Thrust Belt of the Ordos Basin, the quality of the Jurassic sandstone reservoirs is still less studied. Diagenesis and reservoir evaluation are important research contents and hotspots in sedimentary geology. Therefore, in this paper, the diagenesis and reservoir properties of the Jurassic Yan 6 to Yan 10 members (Yan'an Formation) have been systematically studied based on the latest 3D seismic, well logging, cast thin section, scanning electron microscope and petrophysical property tests in this area. Furthermore, the vertical heterogeneity of petrophysical properties of the Jurassic reservoir has been discussed in detail, and the diagenetic evolution sequence and classification criteria of Jurassic sandstone reservoir have been proposed. The research results show that the lithologies of the Yan 6 to Yan 10 members are mainly lithic quartz sandstone, lithic feldspar sandstone and feldspar lithic sandstone. The pore types of sandstone are mainly intergranular pores, followed by dissolution pores, intercrystalline pores and a few microfractures. There are two high‐value porosity zones in the buried depths of 1,950–2,050 m and 2,150–2,250 m, which are the coupling results of dissolution and palaeo‐overpressure. Based on the comprehensive study of petrology, petrophysical properties and diagenesis, the diagenetic evolution sequence of the Jurassic sandstone was restored and a comprehensive classification standard for the Jurassic sandstone reservoirs is proposed. The Jurassic reservoir in the study area is a structural‐lithological reservoir, which has a unified oil–water interface, the Type I and Type II reservoir areas in the structural high positions are conducive to the large‐scale accumulation of hydrocarbons. [ABSTRACT FROM AUTHOR]

When many cities need quantitative forecasts of air quality to adjust industrial production plans and urbanization development, how to build an efficient forecast model remain a challenge. Methodology for quantitative prediction of air quality can no longer rely on single‐site observations, and thus approaches that require fewer input data and are more efficient and more reliable need to be explored. This paper proposes the principles and steps of a new model using the empirical orthogonal function (EOF) and principal component regression (PCR), which is a hybrid EOF‐PCR approach that decomposes the panel data of PM2.5 and predictors into spatial structures (EOFs) and time expansion coefficients (ECs) by EOF analysis, establishes the PCR of the ECs of PM2.5, and simulates the PM2.5 concentrations in each city by projecting the fitted ECs through EOFs. The very heart of the new model is the PCR modeling and projection. The results are presented for PM2.5 concentrations over Jiangsu Province in eastern China. The results show that this EOF‐PCR model, which is based on EC1s with a cumulative variance contribution rate above 90%, has an average prediction accuracy of 65%. The model performs best in spring and autumn, better in summer and worst in winter. Most predictors have a maximum lag of a week, and they are quite different among seasons. Considering the influence of the spatial distributions of predictors, rather than covariates at a single site, this model can reflect regional influences and effectively improve the simulation effect. Plain Language Summary: This study aims to develop a hybrid statistical model for regional forecasting of PM2.5 concentrations using EOF analysis and principal component regression, based on daily observations of PM2.5 concentrations and meteorological predictors. In the study area, the emission sources are relatively fixed, and meteorological conditions represent the main factor affecting short‐term air quality. The panel data of PM2.5 concentration and predictors are decomposed into spatial structures (EOFs) and temporal expansion coefficients (ECs) by EOF analysis. A principal component regression model was built to simulate the ECs of the PM2.5 concentrations, with the ECs of the predictors. Finally, through the inverse operation of the EOF analysis, the fitting values of the PM2.5 ECs are projected as PM2.5 concentrations at each site. The proposed model can reduce input requirements, improve computational efficiency, and emphasize the synergistic effect of meteorological factor distributional modes, rather than a point influence. Key Points: Proposed new regional forecast approach has less demand for input data, especially emissions dataForecasting accuracy was improved and reached nearly 70%, and computational efficiency and speed also increasedPM2.5 concentrations are sensitive to regional distributions of different meteorological predictors, that is, EOFs [ABSTRACT FROM AUTHOR]

Genetic engineering has been a topic of discussion for over 50 years, but it is only recently that gene editing has become a reality. CRISPR biotechnologies have made gene editing much safer, precise and feasible. We have witnessed the first cases of human germline genetic modification resulting in live births, conducted by He Jiankui. In this paper, we will analyse He Jiankui's case in relation to one of the most difficult problems in procreative ethics (or the ethics of future generations): the non‐identity problem. We believe that this analysis will help us to understand the ethics involved in gene editing and hopefully allow for a better, more philosophically grounded legislation on CRISPR and other gene‐editing technologies. [ABSTRACT FROM AUTHOR]

Extreme summer precipitation often associated with flash floods has devastating impact on the local economies and livelihood of millions of people over East China. Tracking down the drivers of those extreme events will help to understand their formation mechanisms and to improve forecasts. Here the synoptic patterns associated with summer extreme precipitation events over East China during 1961-2018 have been identified systematically and quantitatively using a circulation clustering method. The results show that regional events over East China are dominated by the Eastern Asian summer monsoon associated Meiyu front, landfalling tropical cyclones and low-pressure vortices. Most sub-regions have seen increasing trends of extreme rainfall events during the past 6 decades with comparable contributions from the two main drivers. There was a decreasing trend over the North China Plain driven by the lowlevel southeasterly winds. Plain Language Summary Closely linked to flash floods, extreme precipitation is one of the high impacts but low probability weather phenomena that challenge modern numerical predictions. However, models are generally more skillful in predicting synoptic weather systems than precipitation itself. Taking East China as an example, this paper demonstrates the links between extreme precipitation events and synoptic weather systems using circulation clustering. Two major weather systems, the Eastern Asian Summer Monsoon and landfalling tropical cyclones are responsible for most extreme precipitation events (about 70%) over East China during the summer season. If models can accurately predict the strength and position of these weather systems, there may be enhanced potential of predicting regional precipitation extremes. Such implications are not regionally limited. [ABSTRACT FROM AUTHOR]

China is developing its BeiDou Satellite‐Based Augmentation System (BDSBAS) in accordance with international standards, and it has provided initial Single Frequency (SF) and Dual‐Frequency Multi‐Constellation (DFMC) services since July 2020. This paper gives a comprehensive introduction to BDSBAS from the aspects of its general design, system time datum, coordinate reference system and signal characteristics. The performance requirements and internationalization endeavors of BDSBAS also are presented. Additionally, the initial performance tests of BDSBAS SF service had been carried out based on the first two BDSBAS Geosynchronous Earth Orbit (GEO) satellites, including the quality of signal‐in‐space, and initial accuracy, integrity and availability. The results show that the characteristics of BDSBAS signal‐in‐space can well meet the requirements of the International Civil Aviation Organization (ICAO), and the initial performance of BDSBAS SF service can basically meet the requirements of Approach with Vertical guidance I (APV‐I). Finally, before the application of BDSBAS services into civil aviation uses, testing and certification will be organized by the Civil Aviation Administration of China (CAAC) and carried out in three steps. In the future, China will continue to promote the development of BDSBAS in a steady manner in order to provide aviation integrity services compatible with the ICAO standards in China and the surrounding areas as soon as possible. [ABSTRACT FROM AUTHOR]

This paper presents our efforts to characterize the candidate landing region (109°–133°E, 23°–30°N) for Tianwen‐1, China's first mission to Mars, in terms of engineering safety and scientific significance. Topographic analysis reveals that the region has a low elevation around −4,230 m, and 98% of the region have slopes smaller than 8°. The geomorphological mapping and analysis show that the region has an average crater density of about 28 craters (≥200 m in diameter) per 100 square kilometers, with several clusters of high crater densities distributed around the center of the region. There are also pitted cones distributed mainly in the southern part of the region, with a density of approximately 6.6 cones per 100 square kilometers in specific local areas. The region has rock abundances ranging from 1% to 23%, with local clusters of low and high rock abundances. The region comprises four main geological units, including a lowland unit formed in the Late Hesperian and a volcanic unit formed in the Amazonian and Hesperian period. Their specific surface ages are estimated through the analysis of crater size‐frequency distribution. Combining the engineering constraints on surface slopes, crater density, cone density, and rock abundance, a hazard map of the candidate landing region is generated for landing site evaluation and safety assessment. Based on the results, we further discuss the potential scientific outcomes from the exploration in this region. The findings will be helpful for the mission planning and maximization of the scientific return from Tianwen‐1, and complement existing Martian scientific research. Key Points: Topographic, geomorphological, and geologic characterization of the candidate landing region of Tianwen‐1A hazard map of the region combining engineering constraints on slopes, crater density, cone density, and rock abundanceTwo local areas in the region are highlighted as potential landing sites for their low hazard and scientific significance [ABSTRACT FROM AUTHOR]

China has lots of funds, materials, and human resources in cloud seeding operations to help with water shortage problems across the country. But there is little guide about when and where the operations would obtain better benefits. To fill this gap, the modified Water Utilization Level (WUL) map of China mainland was plotted with the acquirable water utilization data on sub‐watershed scales in this study. Then the agricultural drought levels map of different counties were integrated with the modified WUL Map under preset rules to generate an integrated water scarcity map. Lastly, the cloud seeding demand maps of different seasons were drawn by integrating the agricultural drought seasons map of different counties with the integrated water scarcity map and the modified WUL map. Results showed that the middle north of China should have the highest priorities for cloud seeding operations during spring and summer, and some regions at the south during winter and spring, a few scattered regions at the northwest during spring and summer and a few regions at the middle of southeast China during summer and autumn should also have high priorities of cloud seeding operations. This research can help rain enhancement operations to obtain better effects on easing water scarcity problems and deepen the cooperation of water resources department and weather modification department in China. The designed intersecting rules of different maps in this paper also might inspire other relevant researches. Key Points: The results gave a clear demand from water resources field to weather modification department in China mainlandThe middle north areas of China have the severest water scarcity problems, especially during spring and summerSome less developed regions at the south, the northwest and the southeast have high water scarcity levels in different seasons [ABSTRACT FROM AUTHOR]

Several experiments and field observations have demonstrated seismic waves‐induced permeability increases. However, a few experiments have revealed significant decreases in the permeability of fractured sandstone after shaking produced by dynamic stresses. In this paper, we analyze the tidal responses of the water level in two wells (Junan and Dingyuan) situated on and near, respectively, the Tan‐Lu fault in China. The results sampled by a single well indicate that seismic waves could both increase and decrease the permeability. In addition, our results indicate that the earthquakes that decreased the permeability in a single well were distributed in certain azimuthal zones. Given the azimuthal distribution of distant earthquakes, the observed permeability decrease could be attributed to the seismic wave‐induced clogging of fractures that compose the flow paths in the shallow crust. Our research contributes to an enhanced overall understanding of the effects of earthquakes on the permeability of the shallow crust. Plain Language Summary: Most hydrological phenomena caused by earthquakes can be explained by permeability changes. Many experiments and field observations have demonstrated coseismic increases in permeability. However, coseismic decreases in permeability have seldom been reported. In this paper, we analyze the tidal responses of the water level in two wells. The results indicate that seismic waves could both increase and decrease the permeability. In addition, we find that the earthquakes that decreased the permeability in a single well were distributed in certain azimuthal zones. Given the azimuthal distribution of distant earthquakes, the observed permeability decrease could be attributed to the seismic wave‐induced clogging of fractures that compose the flow paths in the shallow crust. Furthermore, we discuss the possible process of particle remobilization in a natural fracture network caused by seismic waves, as this process may be used to explain the azimuthal distribution of earthquakes that decreased the permeability. Our research contributes to an enhanced overall understanding of the effects of earthquakes on the crustal permeability. In the future, earthquake‐induced increases and decreases in permeability should be considered when discussing controls on permeability for exploring underground resources of groundwater, geothermal energy, oil and gas, and for safely storing nuclear and toxic waste underground. Key Points: Seismic waves could decrease besides increase the crustal permeabilityDecreases in permeability may depend on the earthquake azimuthThe decrease in the permeability could be attributed to the clogging of fractures [ABSTRACT FROM AUTHOR]

Drawing upon a panel dataset on China's state‐owned construction land supply at the prefecture level, this paper adopts the spatial panel data model to investigate the existence of spatial dependence in the mechanisms behind China's urban land expansion from 2004 to 2014. The empirical results show that China's urban land expansion has been mainly influenced by a quadruple process of urbanization, industrialization, globalization and decentralization. The strong existence of spatial dependence in China's urban land expansion can be reflected by the significant coefficient estimates of the spatial lags of both the dependent variable and independent variables. [ABSTRACT FROM AUTHOR]

Government-funded urban amenities provide significant values to land markets. This paper uses spatial econometric techniques to recover the puzzling heterogeneity in capitalized values of local amenities such as higher education facilities, transport and environmental amenities. On top of its policy implications, this paper differentiates between non-spatial models and spatial models to allow spatially varying marginal-price estimates and reflect the subtle ways that land markets capitalize local amenities. Our results provide heterogeneous estimates of capitalized amenity values that would affect land development, illustrating the linkage between government-funded amenities and the intensity of land development. [ABSTRACT FROM AUTHOR]

The full deployment of China's BeiDou navigation satellite system (BDS) was finalized in June 2020. To support safety‐critical applications, the system must provide assured signal‐in‐space (SIS) performance. As one of the key steps forward for BDS, this paper characterizes the SIS range errors (SISREs) for both the regional (BDS‐2) and the global (BDS‐3) systems from the integrity perspective. Following the safety standards in aviation, a data‐driven SISRE evaluation scheme is presented in this work. This scheme evaluates the overbounding user range accuracy (URA) and the prior fault probability to respectively capture the nominal and anomalous SIS behaviors. By processing the 4.5‐year ephemerides starting from 2016 for BDS‐2 and the recent 1.5‐year data from 2019 for BDS‐3, we preliminarily provide an overall picture of the BDS SIS characteristics and reveal the significant performance variation among different satellites. [ABSTRACT FROM AUTHOR]

While the relationship between crop yields and the environmental impacts of crop agriculture has been well‐documented, research on the relationship between farm size and the sustainability of cereal production is limited. Using survey data on 120 farms with both small‐ and large‐scale fields in Northeast China, this paper combines a life cycle assessment and the carbon‐based sustainability index (SI) algorithm to examine how maize productivity and agricultural inputs vary with farm size and to clarify how increasing farm size is correlated with energy use efficiency (EUE) and the SI. The results indicate that maize grain yield did not vary with farm size. Increasing farm size was shown to lead to reductions in the areal (per ha) rates of agro‐chemical inputs, energy depletion, and greenhouse gas emissions and increased in EUE and SI. Fertilizer‐ and fuel‐related agricultural inputs dominated the variations of EUE and SI. A scenario analysis indicates that, if farmers adopt a comprehensive management strategy (i.e., machines appropriate to farm size and recommended fertilizer application rates and crop management strategies), EUE and SI would increase by 68.5% (from 4.45 to 7.50) and 74.3% (from 10.1 to 17.6), respectively. Although increasing farm size could benefit maize sustainable production when matched with technical innovation and machinery coordination, supporting smallholder farmers to increase their resource use efficiency and sustainability is also key in China and other regions where smallholder farms comprise a large portion of the cropland area. [ABSTRACT FROM AUTHOR]

Energy consumption and CO2 emissions have been increasing continuously over the past few decades in China and there is a pressing need to replace the fossil fuel‐based economy with an efficient low‐carbon system, tailor‐made to future requirements. China is starting an energy transition with the aim of building an energy system for the future. China has made tremendous progress in increasing the amount of renewable energy and reducing the cost of renewable energy over the last 20 years. According to the 14th 5 year plan, China aims to incorporate 20% of renewable energy to the primary energy mix and attain 27% reduction in CO2 emissions. Bioenergy crops constitute a significant proportion of biomass‐based bioenergy and have recently been promoted by the Chinese Government to help overcome food and fuel conflict. Steps are being taken to promote bioenergy crops on marginal lands in China, and various regions across the country with soil marginality have been evaluated for bioenergy crop cultivation. The present paper reviews the status of bioenergy in China and the potential status of marginal lands from different regions of China. It also elaborates on some of the policies, subsidies and incentives allocated by the Chinese Government for the promotion of biomass‐based energy. Land management and plant improvement strategies were discussed, which are effective in making marginal lands suitable for bioenergy crop cultivation. Managing planting strategies, intercropping and crop rotation are effective management practices used in China for the utilization of marginal lands. A national investigation is desirable for creating an inventory of technical and economic potential of biomass feedstocks that could be planted on marginal lands. This would assist with highlighting the pros and cons of using marginal lands for bioenergy production and effective policy making. [ABSTRACT FROM AUTHOR]

The targets of limiting global warming levels below 2°C or even 1.5°C set by Paris Agreement heavily rely on bioenergy with carbon capture and storage (BECCS), which can remove carbon dioxide in the atmosphere and achieve net zero greenhouse gas (GHG) emission. Biomass and coal co‐firing with CCS is one of BECCS technologies, as well as a pathway to achieve low carbon transformation and upgrading through retrofitting coal power plants. However, few studies have considered co‐firing ratio of biomass to coal based on each specific coal power plant's characteristic information such as location, installed capacity, resources allocation, and logistic transportation. Therefore, there is a need to understand whether it is worth retrofitting any individual coal power plant for the benefit of GHG emission reduction. It is also important to understand which power plant is suitable for retrofit and the associated co‐firing ratio. In order to fulfill this gap, this paper develops a framework to solve these questions, which mainly include three steps. First, biomass resources are assessed at 1 km spatial resolution with the help of the Geography Information Science method. Second, by setting biomass collection points and linear program model, resource allocation and supply chain for each power plants are complete. Third, is by assessing the life‐cycle emission for each power plant. In this study, Hubei Province in China is taken as the research area and study case. The main conclusions are as follows: (a) biomass co‐firing ratio for each CCS coal power plant to achieve carbon neutral is between 40% and 50%; (b) lower co‐firing ratio sometimes may obtain better carbon emission reduction benefits; (c) even the same installed capacity power plants should consider differentiated retrofit strategy according to their own characteristic. Based on the results and analysis above, retrofit suggestions for each power plant are made in the discussion. [ABSTRACT FROM AUTHOR]

This paper seeks to unpack China's grand energy policy in the Middle East. It examines the proposed Iran‐China deal, to which China's great game in Iran presents new challenges. Beijing sees Iran as a key potential asset in Western Asia. Regional experts argue that, given Iran's extensive natural resources and human capital, as well as a relatively untapped market, the country is seen by the Chinese ruling class as a potentially valuable ally. Uncertainty, pessimism, and a deeply rooted culture of resistance against foreign influence and intervention help explain why skepticism about this deal is so pervasive in Iran. A closer look at Iran's history also illustrates that the country's interests would likely be more effectively served if it diversified its economic and political relations with both the West and the East, thus allowing the government to balance its relationship with those countries while retaining a degree of political independence. [ABSTRACT FROM AUTHOR]

In order to seek the optimal growth of China's economy under the premise of natural gas supply safety and air pollution emission constraints, this paper builds a multiobjective optimal allocation model of China's natural gas. The model takes 2012 as the base period, and the simulation period is from 2013 to 2025. Four types of policy combinations are set as variables to be introduced into the model. Lingo is used to simulate the policy combinations under considerations by the model to select the optimal scenario. The dynamic scenario simulation results are as follows: (a) Comparing the simulated data with actual data from 2013 to 2018, we find that the relative error between the simulated results and the actual results is less than 3%, indicating that the constructed multiobjective optimization configuration model is reliable and effective. (b) By 2025, China's natural gas production will be 333.4 billion cubic meters, and its consumption will be 217.1 billion cubic meters. The output will gradually exceed the demand; the proportion of natural gas consumption in the total energy consumption will increase from 5.4% to 7.8%. The proportion has increased significantly; the total GDP is 139 trillion yuan, with an average annual growth rate of 7.5%, and the contribution of the tertiary industry to GDP accounts for 55.8%; (c) China's SO2 emissions from 19.54 million tons in 2013 will be reduced to 12.64 million tons in 2025, China's NOx emissions plummeted from 21.92 million tons in 2013 to 12.59 million tons, and the emission intensity of atmospheric pollutants dropped from 34.0 tons/100 million yuan in 2013 to 9.1 tons/100 million yuan in 2025. [ABSTRACT FROM AUTHOR]

The carbon trading market has become a powerful weapon in alleviating carbon emissions in China, and the carbon price is at the core of its operation. Hence, the carbon trading market serves as an indispensable component in forecasting the carbon price accurately in advance. This paper innovatively explores an ensemble‐driven long short‐term memory network (LSTM) model based on complementary ensemble empirical mode decomposition (CEEMD) for carbon price forecasting, applying it to all eight carbon trading pilots in China. The CEEMD was initially implemented for mode transformation in order to decompose the original complicated mode into a set of simple modes. Then, the partial autocorrelation function selected time‐lagged features as inputs for each mode. Subsequently, the LSTM was used to model the mapping between time‐lagged factors as well as each mode's target values, constructing multiple LSTM models for ensemble learning. Finally, the inverse CEEMD computation was introduced to integrate the anticipated results of the multi‐mode into the final results. Its practical application simultaneously embraced all eight carbon pilots in China, covering their corresponding carbon price data over a considerably long period. The obtained results illustrated that the proposed model driven by ensemble learning possessed sufficient accuracy in carbon price forecasting in China compared with the single LSTM model as well as other conventional artificial neural network models. Furthermore, according to the scope of its application, the innovative model exhibited strong stability and universality. [ABSTRACT FROM AUTHOR]

Most of the crude oil produced in China is highly viscous and easy to condense, and the pipeline transportation method is mostly heated. At present, frequency conversion technology is gradually applied to oil pump units. In order to find the best pipeline operation scheme, this paper is based on MATLAB programming software and established a corresponding mathematical model of oil pipeline energy consumption. This model innovatively takes the rotational speed of the variable frequency pump as one of the model optimization variables, calculating the pressure change and temperature change between stations of the pipeline, predicting the energy consumption of the pipeline and can guide the optimized operation of the pipeline, which has a high popularization and application value. An example of Qingtie Fourth‐line crude oil pipeline shows that among the genetic algorithm, particle swarm optimization, and simulated annealing algorithms for solving the optimization model, the particle swarm optimization algorithm has fast convergence speed, short optimization time, obtains the most optimal scheme, and can reduce energy consumption by 7.84%, which proves the practicability and creativity of the optimization model. [ABSTRACT FROM AUTHOR]

Global food trade has become an increasingly crucial element for feeding the world's population. Enhancing bilateral or multilateral trust in food safety in international food trade is not only important for promoting the sustainable development of trade but is also beneficial for cooperation when facing a global food crisis. However, highly credible traceability systems (TSs) for the cross‐border movement of food are still absent in many countries and regions. Blockchain is regarded as a promising technology that can help build trust for transparency and security issues. In this paper, an interconnected conceptual traceability framework based on blockchain is proposed in order to increase trust in food safety during food trade. Taking the food trade between China and the European Union as an example, a conceptual framework is designed in order to take full advantage of existing TSs in these two locations, and the features of logistical flow, data flow, and blockchain flow are analyzed. Considering the data capacity and data privacy level, a hybrid data storage method combining on‐chain and off‐chain is adopted. Smart contracts according to the features of cross‐border food trade—including the recording of exportation data, exporter inspection data, shipment data, importer inspection data, importation data, and tracing queries—are packaged and deployed to a blockchain network. An effective operation mechanism involving the distribution of related rights for different roles is presented. The blockchain‐based TS framework has the advantages of enhancing bilateral trust in cross‐border food trade, providing a flexible and intelligent technical framework, and having effective operability. Future challenges, such as data security, special smart contracts, and consensus mechanisms, and interoperability with other systems, are discussed. [ABSTRACT FROM AUTHOR]

Understanding the contribution of aboveground dry matter (DM) production and harvest index (HI) to maize grain yield is essential to further improve grain yield to ensure future food growing requirements. In this study, we collected 548 sets of data of DM, HI, and grain yield from a multisite (40 sites) and multiyear (2009–2016) experiment conducted in major maize‐growing regions across China and 615 sets of data from 40 published papers distributed from 1988 to 2018 to assess the performance of DM, HI, and their contributions to grain yield. It was found that the average contribution rate of DM was 73.71%, which was much higher than those of HI (26.28%) across China. For the five different modern hybrids, the contribution rates of DM to grain yield (ranged from 71.36% to 89.10%) were also significantly higher than those of HI (ranged from 10.79% to 28.64%) on a large spatial scale. The significant differences in grain yields between cultivars were mainly due to the differences in HI. Among the four maize‐growing regions, the contribution rates of DM in both NW (57.34%) and NM (64.46%) were higher than those of HI (42.66% and 35.54%, respectively). In contrast, the contribution rates of HI in HM (52.67%) and SW (50.92%) were slightly higher than those of DM (47.33% and 49.08%, respectively). The interregional differences in grain yield were mainly attributed to the differences in DM between regions. Additionally, combining the data of this study and data collected from previous studies, we found that the increase in maize grain yield under lower yield levels (<15 Mg/ha) was mainly attributed to the increase in both DM and HI, while that under higher yield levels (>15 Mg/ha) was mainly dependent on the increase in DM. [ABSTRACT FROM AUTHOR]

Sustainable goals for contemporary world seek viable solutions for interconnected challenges, particularly in the fields of food and energy security and climate change. We present bamboo, one of the versatile plant species on earth, as an ideal candidate for bioeconomy for meeting some of these challenges. With its potential realized, particularly in the industrial sector, countries such as China are going extensive with bamboo development and cultivation to support a myriad of industrial uses. These include timber, fiber, biofuel, paper, food, and medicinal industries. Bamboo is an ecologically viable choice, having better adaptation to wider environments than do other grasses, and can help to restore degraded lands and mitigate climate change. Bamboo, as a crop species, has not become amenable to genetic improvement, due to its long breeding cycle, perennial nature, and monocarpic behavior. One of the commonly used species, moso bamboo (Phyllostachys edulis) is a potential candidate that qualifies as industrial bamboo. With its whole‐genome information released, genetic manipulations of moso bamboo offer tremendous potential to meet the industrial expectations either in quality or in quantity. Further, bamboo cultivation can expect several natural hindrances through biotic and abiotic stresses, which needs viable solutions such as genetic resistance. Taking a pragmatic view of these future requirements, we have compiled the present status of bamboo physiology, genetics, genomics, and biotechnology, particularly of moso bamboo, to drive various implications in meeting industrial and cultivation requirements. We also discuss challenges underway, caveats, and contextual opportunities concerning sustainable development. [ABSTRACT FROM AUTHOR]

Microseisms generated by storms primarily propagate as surface and P waves. However, there has been only one report of S wave microseisms excited by strong storms in the North Atlantic, not from typhoons in the Pacific. In this paper, we present the first observations for S wave microseisms caused by typhoons in Western Pacific, via analyzing ambient seismic waveform recorded by a large‐aperture seismic array in China. The results show that three super typhoons clearly generated S wave microseisms at periods of 5–10 s. The strength of S wave microseism is found to be correlated with P wave. The excitation mechanism for S wave microseism observed in regions with flat seafloor may be related to the interaction between P waves and sub‐ocean sedimentary structure. Plain Language Summary: Besides causing property damages and life losses, ocean storms can also generate seismic waves named as microseisms, which could also be used as signals for studying interior of the Earth. Microseisms mostly propagate as surface waves and P waves. Yet S waves from storms are only detected in the North Atlantic Ocean shown by previous studies. However, there are no reports of S wave microseism by storms in the Pacific Ocean, though the typhoons there are strong and frequent. In this study, we observe and locate S wave microseisms generated by three super typhoons in Western Pacific by processing continuous ambient seismic waveforms recorded in China. The source regions of P and S waves are located very close to each other in the deep ocean near typhoons. Our results show that observability of S wave microseisms depends on P wave energy, which is controlled by strength of typhoons. It is demonstrated that S wave microseisms not only can be generated in the regions with steep topography but also can be excited in the flat seafloor regions. This work is helpful for understanding the excitation mechanism of the S waves. Key Points: We observed body‐wave (P, SV, and probable SH) microseisms from typhoons in the Western PacificWe found that S wave strength is related to P wave power, which in turn relies on typhoon intensityS wave microseisms could be generated in the regions with flat seafloor or bathymetric gradients [ABSTRACT FROM AUTHOR]

With the rapid development of hydraulic fracturing technology, shale gas has become a significant natural gas resource in China. At present, SRV (stimulated reservoir volume) fracturing technology is widely used to exploit shale gas reservoirs. To evaluate the shale gas reserves and design a development plan, a simple and rapid method is needed to predict the production and performance of the multistage fractured horizontal wells with stimulated reservoir volume in shale gas reservoirs. Network fractures with different lengths and widths are not symmetrical to the horizontal well. To account for the complexity of the fracture system and desorption characteristics of shale gas, a semianalytical multiregion seepage model has been established to analyze the performance of multiple fractured horizontal wells. In this paper, a triple‐porosity dual‐permeability model is developed for simulating the flow mechanism of shale gas. Different lengths and widths of network fractures, different fracture intervals, and asymmetry distribution are considered in this model. By employing the principle of Poisson's superposition and Bessel transformation, the fundamental solution of instantaneous point source function has been derived to calculate the pressure response of each hydraulic fracture. Then, the mathematical model for unsteady performance evaluation in multiple fractured horizontal wells has been obtained to simultaneously solve the pressure response of every hydraulic fracture. The sensitivity analysis in terms of the lengths and widths of network fractures, fracture intervals, and the asymmetry distribution of a complex fracture system is presented. The research results show that the SRV morphology will exert a great influence on the performance of multiple fractured horizontal wells. [ABSTRACT FROM AUTHOR]

In traditional opportunistic group replacement maintenance (OGRM) strategy for wind turbines, the reliability thresholds of different subassemblies are set the same and its two‐step optimization for maintenance cost is diseconomy. In this paper, an improved OGRM strategy for wind turbines is proposed. A uniform formulation on maintenance cost concerning different maintenance activities is presented. On the basis of this, an integrated objective function minimizing the maintenance cost is established, and the reliability thresholds of each subassembly of wind turbines are individually severed as the optimization variables of the objective function. The coordinate rotation method is utilized for solving this optimization problem. A maintenance case based on the proposed strategy from a wind farm in North China is implemented, which verifies its superior performance than the traditional opportunistic group maintenance strategy. [ABSTRACT FROM AUTHOR]

Based on daily temperature observation dataset with high quality and spatial resolution, this paper revealed the dominant invading paths of the extreme cold surges (ECSs) within China by using the fifth percentile of temperature drops instead of the traditional unified threshold in the operation. The maximal probabilities of the ECSs from the upstream regions to the down‐stream regions along the invading paths are also provided. Results indicate the distribution of the fifth percentile is quite different in various regions, with the highest value centers of more than 8°C in northern China, and a secondary center of 6–7°C in southern China. While in the areas between the Yellow River basin and the Yangtze River basin, the two longest rivers in China, the values are below 5°C. This result explains the unreasonable frequency gap between the two rivers in previous unified threshold. Based on the distribution, the whole country is roughly divided into 18 regions at an approximate box of 5°N × 10°E to acquire clear and objective invading paths by the lead–lag correlation analysis and an objective identification of the paths. Results show the ECS invading path in northern China has a dominant west or northwest track. But in southern China, the invading paths are more complex, generally from north to south. In China, about 30–40% ECS cases in the upstream regions can lead to the ECSs in the down‐stream regions along the dominant paths. By the identification and the lead–lag correlation, northwestern China could be regarded as the source of ECSs invading other regions. [ABSTRACT FROM AUTHOR]

The solar radiation or insolation at a specific locality on the Earth's surface is determined by the distance of this point from the sun and by the angle with which the radiation hits the earth's surface. The theory that variations in the earth's orbit determine the amount of radiation and therefore the climate which is the Milankovitch Cycle. In non‐marine lacustrine rift basin, the changes of climate can be recorded by the palaeontology, and it also plays an important role in controlling lacustrine fluctuations. The lacustrine fluctuations are indicated by coastal onlap, which is the landward or lake‐ward onlap of non‐marine coastal deposits. In this paper, based on borehole data, wireline logs, seismic datasets, biostratigraphic data and palaeontology, the lacustrine fluctuation curve can be reconstructed from the onlap of lacustrine deposits in non‐marine sequences. The durations and magnitudes of these changes can be used to construct charts showing cycles of the relative rising and falling of lake level. In addition, the changes of lake level can also be reflected by the palaeontology such as pollen. The living conditions and distributions of pollen can be a good indicator for climate changes and lacustrine fluctuations in an a non‐marine setting. The calculation of the Milankovitch Cycle can be determined by the GR log in the study area which keeps a record of cycle changes. All climatic changes and lacustrine fluctuations are mainly resulted from the Milankovitch Cycles, and therefore, through the reconstruction of lacustrine fluctuations, climate changes and the Milankovitch Cycle, the correspondences among them can be clearly addressed. All the results can contribute a lot in theory research in the study area and lead to a new focus in practical hydrocarbon exploration and exploitation. [ABSTRACT FROM AUTHOR]

Devonian is a critical period for reversal of arc polarity and transition of continental margins from passive to active settings in the northern margin of the North China Block (NCB). However, the evolution processes during this period are still poorly constrained due to limited distributions of Devonian magmatism and sedimentary records in the NCB. In this paper, we present new zircon U–Pb geochronological, whole‐rock geochemical and Sr–Nd–Hf isotopic data of some recently identified Devonian volcanic rocks from the Jiefangyingzi area in the northeastern margin of the NCB. The Jiefangyingzi volcanic rocks display a bimodal composition and consist predominantly of amphibolite (meta‐basaltic andesite) and meta‐rhyolite and rhyolitic tuff with minor meta‐andesite. New SHRIMP and LA‐ICP‐MS zircon U–Pb dating results show that the volcanic rocks erupted during the early‐middle Devonian period (397–389 Ma). Geochemical and Sr–Nd–Hf isotopic data indicate that the mafic‐intermediate components were mainly derived from an enriched lithospheric mantle source, and the parental magma experienced fractional crystallization during magma ascent. The felsic rocks were mainly originated by partial melting of ancient lower continental crust, with mixing of some mantle‐derived mafic magmas. The occurrence of Devonian bimodal volcanic rocks, combined with the Devonian alkaline magmatic belt, suggesting that the northern margin of the NCB was a post‐collisional extension environment during the early‐middle Devonian period. In addition, the Sr–Nd–Hf isotopic results of the Devonian felsic volcanic rocks suggest that the Jiefangyingzi area is located in the North China Craton (NCC) rather than the Bainaimiao arc belt, and the orogen‐craton boundary between the northern NCC and Central Asian Orogenic Belt (CAOB) is located in some areas north to the Jiefangyingzi area. [ABSTRACT FROM AUTHOR]

China's first Mars exploration mission (Tianwen‐1), launched on July 23, 2020 with the goal of "orbiting, landing, and roving," and its tentative landing areas (TLAs) are Chryse Planitia (TLA 1) and Isidis‐Elysium Planitia (TLA 2). Dust storm is a typical activity on Mars; it has strong interaction with atmospheric circulation and will influence the visibility of the Martian surface. To ensure the safety and accuracy for landing, it is meaningful to analyze the probability of dust storm activity during Entry‐Descent‐Landing (EDL) season in TLAs. First, based on Mars Orbiter Camera (MOC) and Mars Color Imager (MARCI) Daily Global Maps (MDGMs) from Mars Years 24–31, we identified 882 dust storms within the 2,000 km radius monitor circle of TLA 2 (short for TLA 2‐C). Second, the average daily probability of dust storm activity (Adp_ds) in TLA 2‐C was calculated, with a range of 0% to 14.13% showing obvious seasonality and discontinuity. Third, we divided TLA 2‐C into 0.5° longitude × 0.5° latitude square grids and calculated their spatial probability of dust storm activity. The spatial probability of dust storm in TLA 2‐C ranged from 0% to 11.87% and generally reduced from north to south. Finally, according to the temporal and spatial dust storm probability in TLA 2 during EDL season, we suggested the optimal landing time of China's Tianwen‐1 mission was in Ls = 20–41° and selected five preferred landing areas with the spatial probability of dust storm <3% for this mission. Plain Language Summary: The first China's Mars exploration mission (Tianwen‐1), will achieve the targets of "orbiting, landing, and roving." There are two tentative landing areas (TLAs) in the latitude range of 5–30°, Chryse Planitia (TLA 1) and Isidis‐Elysium Planitia (TLA 2). TLA 2 is on the south of Utopia which is an important origination area of dust storm sequences in the northern hemisphere. The probability of dust storm activity is an important criterion of atmospheric risk assessment for a Martian surface mission. Thus, it is crucial to evaluate the probabilities and characteristics of dust storm activity in and around TLA 2. In this paper, we used Mars Daily Global Maps (MDGMs) of Mars Orbiter Camera (MOC) and Mars Color Imager (MARCI) to (1) identify and catalog the dust storms in and around TLA 2; (2) calculate and analyze the temporal and spatial probability of dust storms in and around TLA 2; and (3) select the preferred landing time and areas for Tianwen‐1 mission based on the temporal and spatial probability of dust storm activity in TLA 2. Key Points: The temporal probability of dust storm activity in Isidis‐Elysium Planitia shows obvious seasonal and inconsecutive activityThe spatial probability of dust storm activity in Isidis‐Elysium Planitia is generally reduced from north to southThe optimal landing time was in Ls = 20–41°, and five preferred landing areas were selected for Tianwen‐1 [ABSTRACT FROM AUTHOR]

Because of China's rapid economic development, its freight transportation system has grown to become one of China's high‐pollution‐emission sectors. However, there are few studies that pay close attention to measuring and improving the environmental performance of China's freight transportation system, especially in regard to seaports. In this paper, data envelopment analysis (DEA) is applied to measure the environmental performance of freight transportation seaports. In addition, we also provide benchmarking information to point the way to improving environmental performance effectively. Our proposed DEA model is based on the closest targets, which satisfies the strong monotonicity and can yield the most relevant solution for the inefficient seaports. An empirical study of 21 of China's primary freight transportation seaports shows that most of them have relatively good environmental performance. Among the five coastal port groups, the Bohai‐rim port group had the best environmental performance, whereas the Pearl River port group had the worst. Our data show significant differences between the best and worst performances, indicating that more measures should be taken to balance and coordinate the development between the five coastal port groups. [ABSTRACT FROM AUTHOR]

A government acts as the main supervisor of food quality and safety. How to quantify and improve the performance and efficiency of government supervision, respectively, is an urgent problem. This study constructs a food safety supervision performance index and utilizes an analytic network process‐fuzzy comprehensive evaluation model to precisely quantify the performance of government supervision. The evaluation results show that, (a) although the overall situation of food quality and safety in China is controllable, the government does not do well in food safety risk supervision, food recall supervision, and accident summary supervision. (b) Internal supervision is the weakest link in food quality and safety supervision. (c) Grassroots supervision is weak especially in prefecture and county levels. (d) There is no positive correlation between the economy level and supervision level in one region. This paper contributes to accurately reflecting the status quo of China's food safety supervision and realizing the transparency of government regulatory information, which ultimately boosts the government's efficiency in food safety supervision and improves the regulatory situation. [ABSTRACT FROM AUTHOR]

Many mines often passively select supports with a higher yield load to avoid the occurrence of support crushing and roof falling during periodic weighting. This method is not conducive to improving production efficiency or reducing mining costs, but it can ensure safe mining. An effective method for overcoming these problems is to determine the reasonable working resistance of the support according to the structural forms of the key strata in the overburden of the stope during periodic weighting. In this paper, comprehensive theoretical analysis, numerical simulation, and field observation were applied to study the discrimination of the key stratum structure (KSS) during periodic weighting and the calculation method of the support load. First, the KSS that affects the periodic weighting of the stope was classified. The "twice discrimination method" was proposed for determining the breaking form of the key strata and the articulated form of the broken blocks. On this basis, the spacing condition that determines whether adjacent key strata interact was analyzed. The discriminant conditions for synergistic breaking between the first subordinate key stratum (SKS1) and the upper key stratum were derived for the cases in which the SKS1 periodically breaks in the form of a cantilever beam, a voussoir beam, and a step beam. These conditions provide the basis for distinguishing the KSS in the overburden of the stope. In addition, mechanical models of the roof structure during periodic weighting were established, and general formulas for calculating the support loads of stopes with a single‐key‐stratum influence structure and a multikey‐stratum influence structure were presented. Finally, five fully mechanized coal faces with various mining conditions in China were considered for engineering verification. The results of this study demonstrate that the proposed method for determining the reasonable working resistance of the support is consistent with the field practice. The research results can provide a reference for roof control and support selection of stopes. [ABSTRACT FROM AUTHOR]

Understanding existing fractures is critical to achieving high and stable yields in low‐permeability reservoirs, tight sandstones, and shale reservoirs. When multiple fracture sets are present in a reservoir, accurately determining the seepage direction of fluids is critical for the deployment of the well network, fracture reformation, and the design of horizontal wells. In this paper, based on conventional logging data calculations and rock triaxial mechanical experiments, a heterogeneous finite element model was established using the finite element software. The densities and the occurrence of the natural fractures were calculated by numerical simulation of the paleostress field; the fracture apertures were calculated numerically by a current in situ stress simulation. Using a combined static coordinate system and dynamic coordinate system approach, a model suitable for determining the 3D permeability tensor of multiple fractures is established, and the formula of the permeability tensor is given. In addition, by adjusting the rotation angle and flip angle in the dynamic coordinate system, the permeability of elements is predicted for different directions. The results show that fractures mainly trend in the NE (45°) and ESE (120°) directions. Additionally, the results of differential strain, microseismic monitoring, stress relief, and regional borehole collapse observations indicate that the dominant direction of the in situ stress field is ENE (70°). The principal values of maximum permeability in the reservoirs in the Chang 71 layer mainly range from 0.05 to 2 × 10−3 μm2, and in the horizontal plane, the direction of maximum principal permeability ranges from 56 to 124°. [ABSTRACT FROM AUTHOR]

Yang et al., Acta Geologica Sinica‐English Edition, 91(2), pp. 749–750 claim that they discovered supercritical hyperpycnal flow deposits in the Early Cretaceous strata on Lingshan Island, East China. We would like to discuss this paper under the following topics: (a) the terminology of "supercritical hyperpycnal flow," (b) hyperpycnal flow deposition, and (c) supercritical flow deposition. Our aim is twofold in that the following debate will help unravel the complexities associated with the controversy around the paleosedimentary environment and sediment dynamic processes of the early Cretaceous deposits on Lingshan Island, in addition to providing an understanding of hyperpycnal flow and supercritical flow deposits. The Beilaishi section deposits on Lingshan Island are more likely storm‐induced tempestites within the lacustrine basin delta front and associated deep lacustrine turbidites. Frequent earthquakes due to tectonic‐magmatic activity are the most likely triggers for lacustrine storms. [ABSTRACT FROM AUTHOR]

The Yinggen‐Ejinaqi Basin (YEB) is located in the central‐southern part of the Central Asian Orogenic Belt (CAOB). Tectonically, the basin is situated at the intersection between the eastern and western CAOB, where Late Palaeozoic strata were well exposed. Hence, it offers a great opportunity to study the deep strata of the eastern CAOB. In this paper, based on extensive studies of Upper Palaeozoic field outcrops and reanalysis of associated geochemical and geochronological data in previous research, the local stratigraphic correlation is established, and the tectonic evolution, sedimentary filling, sedimentary characteristics, and petroleum system of the YEB are discussed. It is revealed that: (a) The filling characteristics of the Upper Palaeozoic strata in YEB are closely related to the closure of the Paleo‐Asian Ocean (PAO). YEB underwent subduction‐related compression during the initial extensional phase of the fore‐arc basin from the Viséan to the Serpukhovian (late Early Carboniferous). During the Bashkirian–Sakmarian interval (Late Carboniferous to Early Permian), it was in subduction‐related fore‐arc and postarc rifting phases. During the Artinskian–Capitanian (Early‐Middle Permian) times, it was in an intracontinental rifting‐depression phase. During the Wuchapingian (Late Permian), it was in an intracontinental compressional phase. Tectonostratigraphy, tectonic evolution, and hydrocarbon potential assessments of the study area show that the Zhusileng Hangwula‐Tost Ul tectonic zone (ZHTUTZ) and southwestern part of Querrshan‐Atasbogd tectonic zone (QATZ) are identified as the main prospective areas for the exploration in the YEB. (b) According to the tectonostratigraphic analysis, tectonic evolution and hydrocarbon system of Carboniferous–Permian in the YEB, the YEB has similar attributes to the basin province in western CAOB (e.g., Santanghu and Junggar basins) and eastern CAOB (Erlian, Songliao Basin). To explore commercial oil and gas in the deeper strata (Carboniferous–Permian) of the eastern CAOB basins, further tectonostratigraphic analyses and comprehensive assessment on hydrocarbon potentials are necessitated in the near future. [ABSTRACT FROM AUTHOR]

Abstract: ‘Community of common destiny’, a new concept in China's diplomacy, has been increasingly used by the Chinese government, especially President Xi Jinping, on international occasions. Given the paucity of academic research on the concept, this paper aims to fill the gap and examine three aspects: meaning, motives and implications. Building upon the author's long observation of China's foreign policy, the paper argues that this concept of ‘community of common destiny’ is vague in meaning and loosely used by China. While initially proposed by China to mend ties with neighbouring states in the context of escalating territorial disputes, the concept constitutes part of China's long‐term strategy to maintain a peaceful ‘period of strategic opportunity’ in the first two to three decades of the 21st century to further develop itself. However, the ambiguity of the concept poses a main challenge for China to promote the acceptance of this concept by the developing world, let alone developed countries. This process demands more transparency, commitment and concrete actions from China. [ABSTRACT FROM AUTHOR]

To study the status quo of research on geological hazards in the Central China Orogen and its geological distribution quantitatively, we used bibliometric methods and deeply analysed the numbers, the authors and research institutions involved, and the distribution and changes of the research contents of papers on geological hazards published from 1962 to 2016. This review involved 26,677 documents, 26,339 authors, and 11,095 research institutions. The results showed that the study of geological hazards has significant time‐domain characteristics. In this field, the greatest number of papers was published in Recent Developments in World Seismology and the Chinese Journal of Geophysics–Chinese Edition, with 456 and 159 papers, respectively. As shown by an analysis of keywords, the current research focuses mainly on the evaluation, distribution characteristics, development regularity, detection and prediction, and prevention and control of geological hazards. The conclusions find that the authors of foreign‐published papers are mostly Chinese researchers, which cannot reflect the status quo of foreign research in this field to a certain extent. Differentiation between domestic and foreign research approaches and objectives through comparative analysis should be further explored. [ABSTRACT FROM AUTHOR]

Solar energy is a clean energy resource, so the large-scale deployment of photovoltaic ( PV) power generation is of great significance for achieving carbon emission reductions in the electric power industry. This paper proposes models and methods for evaluation of the low-carbon benefits of grid-connected PV power generation projects. The carbon emission (or emission reduction) characteristics and the economic benefits of PV generation are analyzed using the following four metrics: generation capacity revenue, PV cost, loss efficiency improvement, and reserve capacity cost. The corresponding low-carbon benefit models and economic benefit models are then established. By combining the low-carbon and economic characteristics of photovoltaic power generation, a model is proposed for evaluating the low-carbon comprehensive benefits ( LCBs) of photovoltaic power generation and the concept of a carbon emission payback period ( CPP) is put forward. Examples with typical operating data from real-world applications are used to verify the validity of the models and methods proposed in this paper. The analysis results show that photovoltaic power generation has great potential in terms of low-carbon comprehensive benefits compared with conventional power generation. [ABSTRACT FROM AUTHOR]

Drawing upon township-level data on high-tech firms of Nanjing, China, this paper adopts a spatial econometric approach to examining the existence of spatial dependence and heterogeneity in the location processes of high-tech firms. The results show that some locational determinants of neighbouring townships exert significant impacts on the attractiveness of a certain township for high-tech firms. Besides, the marginal effects of some locational determinants are found to vary across space. In general, these results point to the need to account for both inter-territorial spillovers and cross-spatial variance in the investigation of factors that influence high-tech firm location. [ABSTRACT FROM AUTHOR]

Abnormal pressure is considered significant for the migration and accumulation of oil and gas. The purpose of this study is to present the lateral and vertical distribution of underpressure conditions in the Huimin Depression determined using the drill stem tests (DSTs) and the well log data. This paper also provides the origins of the underpressure both qualitatively and quantitatively, as well as the effects of the underpressure on the distribution of hydrocarbons. The results show two vertical underpressure units at depths of 1,500–2,500 m and 3,000–4,000 m with a pressure coefficient of 0.8–0.95. Laterally, the underpressure is mainly distributed in the Northern Tectonic Uplift Belt (NTUB) and Southern Slope Belt (SSB). The rock dilation and temperature reduction caused the pressure reductions of 3–4 and 1–3 MPa, respectively. The diffusion of natural gas plays a limited role on the underpressure. An analysis of the lateral seals of faults indicates that the underpressured regions developed in areas with faults with shale gouge ratio (SGR) values larger than 0.6. We propose that the widely distributed underpressure in the Huimin Depression is related to rock dilation, temperature reduction, and fault sealing. An analysis of hydrocarbon migration and reservoirs showed the pumping effect provided by the deficient pressure could make underpressured regions the primary targets for hydrocarbon accumulation, and in the Huimin Depression, underpressure might be more important than overpressure. [ABSTRACT FROM AUTHOR]

The Junggar Basin is one of the main oil basins in Northwest China, and the north‐west part of the basin is a significant petroleum exploration target. Mesozoic structural activity had an important influence on the present structural characteristics of the north‐west Junggar Basin. In this paper, we discuss the tectonic evolution of the Junggar Basin by studying the structural characteristics of the Ke‐Bai Fault. Our results suggest that the Ke‐Bai Fault has obvious strike‐slip characteristics and that it is an important basin‐controlling fault that has controlled the tectonic evolution of the north‐west Junggar Basin. The Junggar Basin was a rift basin in the Early Permian, but it experienced a tectonic reversal during the Middle Permian to the Triassic. The Ke‐Bai Fault changed from a normal fault into a thrust fault from the Early Permian to the Triassic. During the Jurassic, dextral strike‐slip structures developed along the Ke‐Bai Fault, horsetail splay faults developed in its north segment, and there is evidence that it was under WNW–ESE compression. The dextral strike‐slip faulting of the Ke‐Bai Fault is consistent with tectonic movement along the Kelameili, Sangequan, Wu‐Xia, Hong‐Che, and North Tianshan fault systems in the Junggar Basin. We therefore infer that counterclockwise rotation occurred in the Junggar Basin in the Jurassic. [ABSTRACT FROM AUTHOR]

Environmental regulation has been recognized as an important way to directly improve environmental performance or indirectly impact environmental performance through increasing environmental innovation. The present paper constructs an energy and carbon emission total factor productivity index using the Malmquist–Luenberger productivity index and data envelopment analysis. The proposed technique is used to measure the environmental performance of 30 Chinese provinces during the period 2010–2015. The energy and carbon emission total factor productivity measure is divided into a pure technical efficiency index and a technical progress index to provide detailed environmental performance information. Then an ordinary least squares model is adopted to analyse the impact of environmental regulation on environmental innovation operation and environmental performance by hypothesis testing. The empirical results show that environmental regulation and environmental innovation have positive direct effects on environmental performance and that market‐based environmental regulation has a positive indirect effect on environmental performance by increasing environmental innovation. [ABSTRACT FROM AUTHOR]

It is important to evaluate the efficiency of business incubators for their performance improvement. Because few enterprises can successfully graduate from the incubation process in one incubation period, the incubating enterprises will be carried over to the successive periods. In this context, the number of incubating enterprises can be regarded as a carry‐over variable linking different incubation periods, which can also be treated as an undesirable output in the current period. This paper proposes a dynamic slacks‐based measure model to evaluate the efficiency of China's state‐level business incubators during 2010–2012. The empirical results show that neglecting new entrants and the typical carry‐over variable may underestimate the incubation system's efficiency. Moreover, the operational efficiency of China's state‐level business incubators is relatively low, which is largely caused by the lower pure technical efficiency. There exist great disparities between pure technical efficiency and scale efficiency for all considered incubators in China. Some important insights and policy suggestions are presented. [ABSTRACT FROM AUTHOR]

This paper documents the existence of a type of local spillovers—free riding among neighbors—in the diffusion of color television sets (CTVs) in rural China. Consistent with the free‐riding hypothesis, we find that households with no TV (non‐BWTV [black and white television set] households) are less likely to buy their first CTV in villages where a higher fraction of households already own BWTVs. Consistent with the free‐riding hypothesis, we further find that this negative relationship is more pronounced for those non‐BWTV households with lower income, facing lower BWTV ownership rates, and living closer to their neighbors. [ABSTRACT FROM AUTHOR]