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| 1 | 0.9m薄煤层SH型槽波频散特征及波形模式显示文摘在0.9 m薄煤层中使用放炮方法做微震震源的条件,通过对所采集到的薄煤层槽波信号进行分析,发现薄煤层槽波在频域中存在高频和低频两个独立并且不连续的波段.其中高频区大约以2000 Hz为中心,低频域的中心频率约为490 Hz,并且高频域和低频域的能量差异不显著.通过时频分析,可以清晰地看到高、低两个频域几乎在同一时刻触发,并且其小波相关系数在这两个域中的分布规律表现出一定的相似性.通过对0.9 m薄煤层槽波频散曲线的理论分析可知,现场观测到的Airy震相的频率及速度和其理论值较为接近.震源置于煤层中心,且炸药能量对顶底板的扰动,对第二阶对称波形模式下槽波高频部分的形成起着关键作用.在这一对称高阶波形模式下槽波的波速基本上和煤层顶底板中S波的波速一致.由于这两个触发的波形模式在时间域中具有相似的特征,建议在高频域和低频域同时发育较好的薄煤层槽波勘探中,可以采用在同一时间域中高低频相结合的方法提高利用槽波勘探分析的效果. | 杨真 冯涛 WANG Shugang | 2010 | 地球物理学报2010，53，2： | 62 |
| 2 | Predicting geological hazards during tunnel construction显示文摘The complicated geological conditions and geological hazards are challenging problems during tunnel construction,which will cause great losses of life and property.Therefore,reliable prediction of geological defective features,such as faults,karst caves and groundwater,has important practical significances and theoretical values.In this paper,we presented the criteria for detecting typical geological anomalies using the tunnel seismic prediction(TSP) method.The ground penetrating radar(GPR) signal response to water-bearing structures was used for theoretical derivations.And the 3D tomography of the transient electromagnetic method(TEM) was used to develop an equivalent conductance method.Based on the improvement of a single prediction technique,we developed a technical system for reliable prediction of geological defective features by analyzing the advantages and disadvantages of all prediction methods.The procedure of the application of this system was introduced in detail.For prediction,the selection of prediction methods is an important and challenging work.The analytic hierarchy process(AHP) was developed for prediction optimization.We applied the newly developed prediction system to several important projects in China,including Hurongxi highway,Jinping II hydropower station,and Kiaochow Bay subsea tunnel.The case studies show that the geological defective features can be successfully detected with good precision and efficiency,and the prediction system is proved to be an effective means to minimize the risks of geological hazards during tunnel construction. | Shucai Li Shuchen Li Qingsong Zhang Yiguo Xue Bin Liu Maoxin Su Zhechao Wang Shugang Wang | 2010 | Journal of Rock Mechanics and Geotechnical Engineering2010，2，3： | 25 |
| 3 | Changes in Lignin Content and Activity of Related Enzymes in the Endocarp During the Walnut Shell Development Period显示文摘Lignification was observed using the phloroglucinol–HCl method and the content of lignin,cellulose,and polyphenol and the activity of related enzymes were measured during development with the materials of walnut of ‘Zanmei' and ‘Zhenzhuxiang'.Results showed that lignification occurred at the beginning of June,initially took shape in mid-June and finished in late July.From shell lignification to harvest,the concentrations of lignin,cellulose,and phenolic content increased before harvest,but phenolic content decreased slightly.The activities of both POD and PAL decreased and PPO varied somewhat.Correlation analysis showed lignin content to be significantly positively correlated with the cellulose content.Phenolic content had a significant positive correlation with that of lignin.Phenolic content was positively correlated with cellulose.The activity of POD had a significant negative correlation with lignin,cellulose,and phenolic content,but it was positively correlated with the activity of PAL. | ZHAO Shugang WEN Jing WANG Hongxia ZHANG Zhihua LI Xibo | 2016 | Horticultural Plant Journal2016，2，3： | 11 |
| 4 | Numerical simulation of influence of Langmuir adsorption constant on gas drainage radius of drilling in coal seam显示文摘To determine reasonable distance of gas pre-drainage drillings in coal seams, a solid–gas coupling model that takes gas adsorption effect into account was constructed. In view of different adsorption constants,the paper conducted the numerical simulation of pre-drainage gas in drillings along coal seam, studied the relationship of adsorption constants and permeability, gas pressure, and effective drainage radius of coal seams, and applied the approach to the layout of pre-drainage gas drillings in coal seams. The results show that the permeability of coal seams is on the gradual increase with time, which is divided into three sections according to the increase rate: the drainage time 0–30 d is the sharp increase section;30–220 d is the gradual increase section; and the time above 200 d is the stable section. The permeability of coal seams is in negative linear and positive exponent relation with volume adsorption constant VLand pressure adsorption constant PL, respectively. The effective drainage radius is in negative linear relation with VLand in positive exponent relation with PL. Compared with the former design scheme, the engineering quantity of drilling could be reduced by 25%. | Lin Haifei Huang Meng Li Shugang Zhang Chao Cheng Lianhua | 2016 | International Journal of Mining Science and Technology2016，26，3： | 10 |
| 5 | Rapid decompression and desorption induced energetic failure in coal显示文摘In this study, laboratory experiments are conducted to investigate the rapid decompression and desorption induced energetic failure in coal using a shock tube apparatus. Coal specimens are recovered from Colorado at a depth of 610 m. The coal specimens are saturated with the strong sorbing gas CO2 for a certain period and then the rupture disc is suddenly broken on top of the shock tube to generate a shock wave propagating upwards and a rarefaction wave propagating downwards through the specimen.This rapid decompression and desorption has the potential to cause energetic fragmentation in coal.Three types of behaviors in coal after rapid decompression are found, i.e. degassing without fragmentation, horizontal fragmentation, and vertical fragmentation. We speculate that the characteristics of fracture network(e.g. aperture, spacing, orientation and stiffness) and gas desorption play a role in this dynamic event as coal can be considered as a dual porosity, dual permeability, dual stiffness sorbing medium. This study has important implications in understanding energetic failure process in underground coal mines such as coal gas outbursts. | Shugang Wang Derek Elsworth Jishan Liu | 2015 | Journal of Rock Mechanics and Geotechnical Engineering2015，7，3： | 10 |
| 6 | Catastrophic mechanism of coal and gas outbursts and their prevention and control显示文摘Based on the engineering observations of coal and gas outbursts during mining processes and the experimental results,we built a thin plate mechanical model for layered and spalled coal bodies.We studied the mechanical mechanism of outbursts,due to instability,of thin plates of coal rocks under the action of in-plane load and normal load,by using the catastrophe theory.The total potential function is derived for the layered rock system,the cusp catastrophe model for the system is established,the bifurcation set that makes the system unstable is given,the process in which gradual change of action forces leads to catastrophic change of state is analyzed,and the effect of movement path of point(P,q) in the control space on the stability of rock plate is analyzed.The study results show that during the process of coal mining,the stability of the layered coal bodies depends not only on its physical properties and dimensions but also on the magnitudes and changing paths of the in-plane load and the normal load.When the gas in the coal bodies ahead of the mining face is pre-drained,the gas pressure can be reduced and the normal load q can be lowered.Consequently,disasters such as coal and gas outbursts can be effectively prevented. | LI, Shugang ZHANG, Tianjun | 2010 | Mining Science and Technology2010，20，2： | 10 |
| 7 | Synthesis of a novel ternary HA/Fe-Mn oxides-loaded biochar composite and its application in cadmium(Ⅱ) and arsenic(Ⅴ) adsorption显示文摘Cadmium (Cd) and arsenic (As) are two of the most toxic elements.However,the chemical behaviors of these two elements are different,making it challenging to utilize a single adsorbent with high adsorption capacity for both Cd(Ⅱ) and As(Ⅴ) removal.To solve this problem,we synthesized HA/Fe-Mn oxides-loaded biochar (HFMB),a novel ternary material,to perform this task,wherein scanning electron microscopy (SEM) combined with EDS (SEM-EDS) was used to characterize its morphological and physicochemical properties.The maximum adsorption capacity of HFMB was 67.11 mg/g for Cd(Ⅱ) and 35.59 mg/g for As(Ⅴ),which is much higher compared to pristine biochar (11.06 mg/g,0 mg/g for Cd(Ⅱ) and As(Ⅴ),respectively).The adsorption characteristics were investigated by adsorption kinetics and the effects of the ionic strength and pH of solutions.X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) revealed that chelation and deposition were the adsorption mechanisms that bound Cd(Ⅱ) to HFMB,while ligand exchange was the adsorption mechanism that bound As(Ⅴ). | Jianhua Guo Changzhou Yan Zhuanxi Luo Hongda Fang Shugang Hu Yinglan Cao | 2019 | Journal of Environmental Sciences2019，31，11： | 10 |
| 8 | Late Paleozoic reefs and their significance for tectonics and oil-gas exploration in the Hinggan-Inner Mongolia area显示文摘Many reefs of the Late Paleozoic have been discovered recently in the Hinggan-Inner Mongolia area.These reefs clearly are geographically extensive,and possess distinctive features and well-developed reef-facies.They have been found to contain five reef-building communities and were constructed in four periods.Colonial coral-algal reefs at Aohan and Chifeng represent a warm shallow-sea in the Carboniferous.Different reefs in the Xiwu Banner were formed in three periods:early Late Carboniferous,late Late Carboniferous and Early Permian.These reefs were built in warm sea conditions.Their buildup types include colonial coral frameworks,algae-buildings and lime-mud mounds.Bryozoan reefs in the Zhalaite and Dongwu banners were built in the late Middle Permian and thrived in a cold shallow-sea.All reefs grew independently on two kinds of sedimentary platforms,carbonate and carbonate-clastic mixed platforms.Four reef-forming periods occurred later from south to north,along a collisional course between the North China Plate and the Siberian Plate.These reefs can be arranged into three 'reef-links' or reef zones that extend along plate margins.Among these,the Aohan-Chifeng reef-link indicates a northern margin of the North China Plate,the Zhalaite-Dongwu reef-link marks a southern margin of the Siberian Plate,and the Xiwu-Beishan reef-link reflects the former existence of some inter-plates.The strata of each reef-facies are thick and contain rich asphalt deposits.Overlapping and heteropic layers are very thick and contain dark oil/gas-rich horizons;TOC analyses verify that most of these are good hydrocarbon source rocks.This study shows that the study area is an excellent candidate for oil-gas exploration. | TIAN ShuGang ZHANG YongSheng WANG JunTao NIU ShaoWu | 2011 | Science China Earth Sciences2011，54，2： | 8 |
| 9 | Record Low Sea-Ice Concentration in the Central Arctic during Summer 2010显示文摘The Arctic sea-ice extent has shown a declining trend over the past 30 years. Ice coverage reached historic minima in 2007 and again in 2012. This trend has recently been assessed to be unique over at least the last 1450 years. In the summer of 2010, a very low sea-ice concentration(SIC) appeared at high Arctic latitudes—even lower than that of surrounding pack ice at lower latitudes. This striking low ice concentration—referred to here as a record low ice concentration in the central Arctic(CARLIC)—is unique in our analysis period of 2003–15, and has not been previously reported in the literature. The CARLIC was not the result of ice melt, because sea ice was still quite thick based on in-situ ice thickness measurements.Instead, divergent ice drift appears to have been responsible for the CARLIC. A high correlation between SIC and wind stress curl suggests that the sea ice drift during the summer of 2010 responded strongly to the regional wind forcing. The drift trajectories of ice buoys exhibited a transpolar drift in the Atlantic sector and an eastward drift in the Pacific sector,which appeared to benefit the CARLIC in 2010. Under these conditions, more solar energy can penetrate into the open water,increasing melt through increased heat flux to the ocean. We speculate that this divergence of sea ice could occur more often in the coming decades, and impact on hemispheric SIC and feed back to the climate. | JinpingZHAO David BARBER Shugang ZHANG Qinghua YANG Xiaoyu WANG Hongjie XIE | 2018 | Advances in Atmospheric Sciences2018，35，1： | 7 |
| 10 | Olfactory ensheathing cell transplantation improves sympathetic skin responses in chronic spinal cord injury显示文摘Forty-three patients with chronic spinal cord injury for over 6 months were transplanted with embryonic olfactory ensheathing cells, 2–4 × 106, into multiple sites in the injured area under the surgical microscope. The sympathetic skin response in patients was measured with an electromyography/evoked potential instrument 1 day before transplantation and 3–8 weeks after transplantation.Spinal nerve function of patients was assessed using the American Spinal Injury Association impairment scale. The sympathetic skin response was elicited in 32 cases before olfactory ensheathing cell transplantation, while it was observed in 34 cases after transplantation. Concomitantly,sympathetic skin response latency decreased significantly and amplitude increased significantly after transplantation. Transplantation of olfactory ensheathing cells also improved American Spinal Injury Association scores for movement, pain and light touch. Our findings indicate that olfactory ensheathing cell transplantation improves motor, sensory and autonomic nerve functions in patients with chronic spinal cord injury. | Zuncheng Zheng Guifeng Liu Yuexia Chen Shugang Wei | 2013 | Neural Regeneration Research2013，8，30： | 6 |
| 11 | Infrared measurement of temperature field in coal gas desorption显示文摘In order to reveal the temperature change in coal gas desorption process,the temperature variation in coal gas desorption process under different particle sizes is analyzed with infrared thermal imager.The infrared video signals obtained by the experiment are processed with SAT.Then the infrared radiation signals are processed by EMD with Hilbert–Huang and the infrared radiation noise is effectively removed.The research results show that the desorption process,with the change of the temperature,is an endothermic process.The coal absorbs heat when the gas is desorbed and the temperature drops.The coal body temperature drop range is obviously related to coal particle size.The smaller the particle size is,the bigger the temperature drop becomes.The temperature variation curves in the process of coal gas desorption under different particle sizes are fitted,and they comply with the exponential function.The research results lay the theoretical and experimental foundation for non-contact prediction on working face of coal and gas outburst with infrared thermal image technology. | Liu Jikun Wang Cuixia He Xueqiu Li Shugang | 2014 | International Journal of Mining Science and Technology2014，24，1： | 6 |
| 12 | Discovery of marine fossils in the upper part of the Permian Linxi Formation in Lopingian, Xingmeng area, China显示文摘Two important geological issues have a long history of debate in the Xingmeng area.The first concerns the final closure of the North China plate,Siberia plate and several intermediate massifs in the area,and the other concerns the folding and lifting of the Xingmeng Trough.Disagreements arise because of issues involving the tectonicpalaeogeographical environment of the Upper Permian deposits of the Linxi Formation.The Linxi Formation(Upper Permian)is generally considered to be either an exclusively continental deposit or separated into marineterrigenous facies deposited during the Lower to Middle Linxi Period and continental deposits in the Upper Linxi Period.However,in this study,large numbers of bryozoan and sponge spicule fossils were discovered for this first time in the thick limestone layers and lenses of the upper part of the Linxi Formation found in the Guandi section of Linxi county in eastern Inner Mongolia.At the same time,abundant bryozoan fossils were also found in sedimentary tuff slices that were collected from the upper part of the Taohuayingzi Formation from the Taohuayingzi section in Ar Horqin Banner,and abundant small connecting body crinoid stem fossils were found in the dark shale of the Yangjiagou Formation from the Yangjiagou section of Jiutai county,Jilin Province.These marine fossils provide the first evidence that the Xingmeng area was still a marine or mainly marine environment at the end of the late Permian.This not only provides conclusive evidence for the recognition of the above two major geological issues but also promotes changes in the approach towards research,exploration and development of oil and gas,shale gas(oil),and other mineral resources that are preserved in the late Permian layers of the Northeast-Xingmeng area. | Yongsheng Zhang Shugang Tian Zishun Li Yuexuan Gong Enyuan Xing Zhuozhuo Wang Daxing Zhai Cao Jie Su Kui Wang Meng | 2014 | Chinese Science Bulletin2014，59，1： | 6 |
| 13 | Early-Middle Permian Reef Frameworks and Reef-building Models in the Eastern Kunlun Mountains显示文摘Reef frameworks and building models of the Early-Middle Permian in the eastern Kunlun Mountains have been verified through studies of reef-building communities, palaeoecology and carbonate facies. The eastern Kunlun reefs are built mainly by 6 reef-building communities, which include 11 major categories of frame-building organisms and 6 categories of reef-associated organisms. Eight types of reef-frames have been distinguished and eleven kinds of rocks identified to belong to 6 reef facies. Three sorts of reefs classified by previous researchers, namely mudmounds, knoll reefs and walled reefs, are well developed in the study area. Such reef-facies association and reef distribution show that there are 4 models of reef growth and development, i.e. the tidal-bank knoll-reef model, the plateau-margin wall-reef model, the composite wall-reef model and the deep-water mudmound model. The reefs are mainly constructed by calcareous sponge and calcareous algae, which are similar to all Permian reefs in other areas of South China and the world. Their great scales indicate a secular stable platform-marginal environment. | TIAN Shugang Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037and FAN Jiasong Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 | 2001 | Acta Geologica Sinica(English Edition)2001，75，2： | 5 |
| 14 | Pseudomonas aeruginosa:pathogenesis,virulence factors,antibiotic resistance,interaction with host,technology advances and emerging therapeutics显示文摘Pseudomonas aeruginosa(P.aeruginosa)is a Gram-negative opportunistic pathogen that infects patients with cystic fibrosis,burn wounds,immunodeficiency,chronic obstructive pulmonary disorder(COPD),cancer,and severe infection requiring ventilation,such as COVID-19.P.aeruginosa is also a widely-used model bacterium for all biological areas.In addition to continued,intense efforts in understanding bacterial pathogenesis of P.aeruginosa including virulence factors(LPS,quorum sensing,two-component systems,6 type secretion systems,outer membrane vesicles(OMVs),CRISPR-Cas and their regulation),rapid progress has been made in further studying host-pathogen interaction,particularly host immune networks involving autophagy,inflammasome,noncoding RNAs,cGAS,etc.Furthermore,numerous technologic advances,such as bioinformatics,metabolomics,scRNA-seq,nanoparticles,drug screening,and phage therapy,have been used to improve our understanding of P.aeruginosa pathogenesis and host defense.Nevertheless,much remains to be uncovered about interactions between P.aeruginosa and host immune responses,including mechanisms of drug resistance by known or unannotated bacterial virulence factors as well as mammalian cell signaling pathways.The widespread use of antibiotics and the slow development of effective antimicrobials present daunting challenges and necessitate new theoretical and practical platforms to screen and develop mechanism-tested novel drugs to treat intractable infections,especially those caused by multi-drug resistance strains.Benefited from has advancing in research tools and technology,dissecting this pathogen’s feature has entered into molecular and mechanistic details as well as dynamic and holistic views.Herein,we comprehensively review the progress and discuss the current status of P.aeruginosa biophysical traits,behaviors,virulence factors,invasive regulators,and host defense patterns against its infection,which point out new directions for future investigation and add to the design of novel and/or alternative therapeutics to combat this clinically significant pathogen. | Shugang Qin Wen Xiao Chuanmin Zhou Qinqin Pu Xin Deng Lefu Lan Haihua Liang Xiangrong Song Min Wu | 2022 | Signal Transduction and Targeted Therapy2022，7，7： | 5 |
| 15 | Surface Heat Budget and Solar Radiation Allocation at a Melt Pond During Summer in the Central Arctic Ocean显示文摘The heat budget of a melt pond surface and the solar radiation allocation at the melt pond are studied using the 2010 Chinese National Arctic Research Expedition data collected in the central Arctic. Temperature at a melt pond surface is proportional to the air temperature above it. However, the linear relationship between the two varies, depending on whether the air temperature is higher or lower than 0℃. The melt pond surface temperature is strongly influenced by the air temperature when the latter is lower than 0℃. Both net longwave radiation and turbulent heat flux can cause energy loss in a melt pond, but the loss by the latter is larger than that by the former. The turbulent heat flux is more than twice the net longwave radiation when the air temperature is lower than 0℃. More than 50% of the radiation energy entering the pond surface is absorbed by pond water. Very thin ice sheet on the pond surface(black ice) appears when the air temperature is lower than 0℃; on the other hand, only a small percentage(5.5%) of net longwave in the solar radiation is absorbed by such a thin ice sheet. | ZHANG Shugang ZHAO Jinping SHI Jiuxin JIAO Yutian | 2014 | Journal of Ocean University of China2014，13，1： | 5 |
| 16 | Olfactory ensheathing cell transplantation in 106 patients with old spinal cord injury Differences in ages,sexes,disease courses,injured types and sites显示文摘BACKGROUND: It has been demonstrated that the transplantation of olfactory ensheathing cell (OEC) can promote the recovery of neurological function through ameliorating the local internal environment in spinal cord injury. OBJECTIVE: To evaluate the recent efficacy of OEC transplantation on old spinal cord injury. DESIGN: A self-controlled experiment. SETTING: Department of Neurosurgery,Taian Rongjun Hospital of Shandong Province. PARTICIPANTS: Totally 106 inpatients with old spinal cord injury were selected from the Department of Neurosurgery,Taian Rongjun Hospital of Shandong Province from June 2004 to December 2006,including 97 males and 9 females. Inclusive criteria: ① Complete data; ② Informed with the fact; ③ No further recover neurological function after drug therapy (neurotrophic factor,GM-1),traditional Chinese medicine,physiotherapy and rehabilitative exercises; ④ No obvious compression of the injured spinal cord displayed by MRI examination. METHODS: ① The olfactory bulb was obtained from embryo of induced labor in middle pregnancy above 4 months supplied voluntarily by pregnant women,and the survived cells after purification and culture for 1-2 weeks were collected. Dura mater was incised by posterior approach,then the cultured OEC suspension was transplanted to corresponding regions by means of multi-target injection using microscope. ② The patients were evaluated for twice with the standards suggested by American Spinal Injury Association (ASIA) at admission and 2-4 weeks postoperatively,in order to investigate the efficacy in different age groups,different sites and at different time points after the OEC transplantation. ③ Standards for evaluation: The International Standard for Neurological and Functional Classification of Spinal Cord Injury set by ASIA: The highest score of motor function was 100 points; The highest score of sensory function was 112 points for light touch and 112 for acupuncture sense. Frankel grading modified by ASIA in 1992: grades A,B,C,D and E (grade A for complete injury,and grade E for normal). ④ The data were statistically processed by Professor Cheng from the Department of Statistics,Taishan Medical College. MAIN OUTCOME MEASURES: Changes of motor and sensory functions postoperatively. RESULTS: All the 106 patients with old spinal cord injury were involved in the analysis of results. Grade A (n =72) at admission recovered to grade B in 31 cases and grade C in 7 cases after operation; Grade B (n =9) recovered to grade C in 2 cases; Grade C (n =15) recovered to grade D in 4 cases; Grade D (n =10) recovered to grade E in 1 cases,which referred to normal sensory and motor functions. The scores of motor,tactile sensation and pain sensation postoperatively were all obviously higher than those at admission (t =5.381,7.036,7.775,P < 0.05). The recovery of motor function had obvious difference among patients of different ages (F =5.235,P =0.001). There were no obvious differences in the recovery of motor and sensory functions among patients of different sexes,courses,injured types and sites. CONCLUSION: The neurological function can be ameliorated in a short time after OEC transplantation in patients with old spinal cord injury. The efficacy is generally the same in patients of different sexes,courses,injured types and sites,but there are differences in the effects on motor function of patients of different ages. | Zuncheng Zheng Chao Liu Lin Zhang Rui Gao Shugang Wei Kun Zhang Lei Zhang | 2007 | Neural Regeneration Research2007，2，6： | 5 |
| 17 | Phylogeny and divergence of Chinese Angiopteridaceae based on chloroplast DNA sequence data (rbcL and trnL-F)显示文摘Marattioid ferns are an ancient lineage of primitive vascular plants that first appeared in the middle Carboniferous. Extant members are almost exclusively restricted to tropical regions, and the spe- cies-rich family Angiopteridaceae are limited in their distribution to the eastern hemisphere; relation- ships within the group are currently vague. Here the phylogenetic relationship between Angiopteris Hoffm. and Archangiopteris Christ et Gies. was evaluated based on the sequence analysis of chloro- plast rbcL gene and trnL-F intergenic spacer with MEGA2 and MrBayes v3.0b4. On the basis of the phy- logenetic pattern and fossil record, we further estimated the divergence time for the two genera. The phy- logenetic trees revealed that all species of Angiopteris and Archangiopteris in this study formed a monophyletic group with strong statistical support, but the relationship between the two genera re- mained unresolved based on individual sequence analysis. On the other hand, the sequence analyses of combined data set revealed that Archangiopteris species diverged first, indicating that Archangiop- teris may not be a direct derivative as traditionally assumed. The clade of Angiopteris and Archan- giopteris appears to have diversified in the late Oligocene (≈26 Ma) based on the molecular estimate. Thus, the evolutionary history of extant Angiopteris and Archangiopteris has been characterized by ancient origin and recent diversification, and these groups are not relic and endangered lineages as traditionally considered. | LI ChunXiang LU ShuGang | 2007 | Chinese Science Bulletin2007，52，1： | 4 |
| 18 | Optimal Predictive Control for Path Following of a Full Drive-by-Wire Vehicle at Varying Speeds显示文摘The current research of the global chassis control problem for the full drive-by-wire vehicle focuses on the control allocation(CA) of the four-wheel-distributed traction/braking/steering systems. However, the path following performance and the handling stability of the vehicle can be enhanced a step further by automatically adjusting the vehicle speed to the optimal value. The optimal solution for the combined longitudinal and lateral motion control(MC)problem is given. First, a new variable step-size spatial transformation method is proposed and utilized in the prediction model to derive the dynamics of the vehicle with respect to the road, such that the tracking errors can be explicitly obtained over the prediction horizon at varying speeds. Second, a nonlinear model predictive control(NMPC) algorithm is introduced to handle the nonlinear coupling between any two directions of the vehicular planar motion and computes the sequence of the optimal motion states for following the desired path. Third, a hierarchical control structure is proposed to separate the motion controller into a NMPC based path planner and a terminal sliding mode control(TSMC) based path follower. As revealed through off-line simulations, the hierarchical methodology brings nearly 1700% improvement in computational efficiency without loss of control performance. Finally, the control algorithm is verified through a hardware in-the-loop simulation system. Double-lanechange(DLC) test results show that by using the optimal predictive controller, the root-mean-square(RMS) values of the lateral deviations and the orientation errors can be reduced by 41% and 30%, respectively, comparing to those by the optimal preview acceleration(OPA) driver model with the non-preview speed-tracking method. Additionally,the average vehicle speed is increased by 0.26 km/h with the peak sideslip angle suppressed to 1.9°. This research proposes a novel motion controller, which provides the full drive-by-wire vehicle with better lane-keeping and collision-avoidance capabilities during autonomous driving. | Pan SONG Bolin GAO Shugang XIE Rui FANG | 2017 | Chinese Journal of Mechanical Engineering2017，30，3： | 4 |
| 19 | miR395-regulated sulfate metabolism exploits pathogen sensitivity to sulfate to boost immunity in rice显示文摘MicroRNAs (miRNAs) play important roles in plant physiological activities. However, their roles and molecular mechanisms in boosting plant immunity, especially through the modulation of macronutrient metabolism in response to pathogens, are largely unknown. Here, we report that an evolutionarily conserved miRNA, miR395, promotes resistance to Xanthomonas oryzae pv. oryzae (Xoo) and X. oryzae pv. oryzicola (Xoc), two destructive bacterial pathogens, by regulating sulfate accumulation and distribution in rice. Specifically, miR395 targets and suppresses the expression of the ATP sulfurylase gene OsAPS1, which functions in sulfate assimilation, and two sulfate transporter genes, OsSULTR2;1 and OsSULTR2;2, which function in sulfate translocation, to promote sulfate accumulation, resulting in broad-spectrum resistance to bacterial pathogens in miR395-overexpressing plants. Genetic analysis revealed that miR395-triggered resistance is involved in both pathogen-associated molecular pattern-triggered immunity and R gene-mediated resistance. Moreover, we found that accumulated sulfate but not S-metabolites inhibits proliferation of pathogenic bacteria, revealing a sulfate-mediated antibacterial defense mechanism that differs from sulfur-induced resistance. Furthermore, compared with other bacteria, Xoo and Xoc, which lack the sulfate transporter CysZ, are sensitive to high levels of extracellular sulfate. Accordingly, miR395-regulated sulfate accumulation impaired the virulence of Xoo and Xoc by decreasing extracellular polysaccharide production and biofilm formation. Taken together, these results suggest that rice miR395 modulates sulfate metabolism to exploit pathogen sensitivity to sulfate and thereby promotes broad-spectrum resistance. | Zeyu Yang Shugang Hui Yan Lv Miaojing Zhang Dan Chen Jingjing Tian Haitao Zhang Hongbo Liu Jianbo Cao Wenya Xie Changyin Wu Shiping Wang Meng Yuan | 2022 | Molecular Plant2022，15，4： | 3 |
| 20 | Identification methods for anomalous stress region in coal roadways based on microseismic information and numerical simulation显示文摘It is believed that the microseismicity induced by mining effect and gas gradient disturbance stress is a precursor to the essential characteristics of roadway unstability. In order to effectively identify and evaluate the stability of coal roadways in the process of mine development and extraction, a microseismic monitoring system was deployed for the study of the stress evolution process, damage degree and distribution characteristics in the tailgate and headgate. The mine under study is the 62113 outburst working face of Xin Zhuangzi coalmine in Huainan mining area. The whole process of microfractures initiation,extension, interaction and coalescence mechanisms during the progressive failure processes of the coal rock within the delineated and typical event clusters were investigated by means of a two dimensional realistic failure process analysis code(RFPA2D-Flow). The results show that the microseismic events gradually create different-sized event clusters. The microseismicity of the tailgate is significantly higher than that of the headgate. The study indicates that the greater anomalous stress region matches the area where microfractures continuously develop and finally connect to each other and form a fissure zone.Due to the mine layout and stress concentration, the ruptured area is mainly located on the left shoulder of the tailgate roof. The potential anomalous stress region of the coal roadway obtained by numerical simulation is relatively in good agreement with the trend of spatial macro evolution of coal rock microfractures captured by the microseismic monitoring system. The research results can provide important basis for understanding instability failure mechanism of deep roadway and microseismic activity law in complex geologic conditions, and it ultimately can be used to guide the selection and optimization of reinforcement and protection scheme. | Liu Chao Li Shugang Cheng Cheng Cheng Xiaoyu | 2017 | International Journal of Mining Science and Technology2017，27，3： | 3 |
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