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| 1 | Prognostic value of systemic immune.inflammation index in patients with gastric cancer显示文摘Background:Inflammation-based indexes have been used to predict survival and recurrence in cancer patients.Systemic immune-inflammation index(Sll) was reported to be associated with prognosis in some malignant tumors.In the present study,we aimed to explore the association between Sll and the prognosis of patients with gastric cancer.Methods:We retrospectively analyzed data from 444 gastric cancer patients who underwent gastrectomy at the First Affiliated Hospital of Sun Yat-sen University between January 1994 and December 2005.Preoperative Sll was calculated.The Chi square test or Fisher's exact test was used to determine the relationship between preoperative Sll and clinicopathologic characteristics.Overall survival(OS) rates were estimated using the Kaplan-Meier method,and the effect of Sll on OS was analyzed using the Cox proportional hazards model.Receiver operating characteristic(ROC)curves were used to compare the predictive ability of Sll,NLR,and PLR.Results:Sll equal to or higher than 660 was significantly associated with old age,large tumor size,unfavorable Borrmann classification,advanced tumor invasion,lymph node metastasis,distant metastasis,advanced TNM stage,and high carcino-embryonic antigen level,high neutrophil-lymphocyte ratio,and high platelet-lymphocyte ratio(all P<0.05).High Sll was significantly associated with unfavorable prognosis(P<0.001) and Sll was an independent predictor for OS(P=0.015).Subgroups analysis further showed significant associations between high Sll and short OS in stage Ⅰ,Ⅱ,Ⅲ subgroups(all P<0.05).Sll was superior to NLR and PLR for predicting OS in patients with gastric cancer.Conclusion:Preoperative Sll level is an independent prognostic factor for OS in patients with gastric cancer. | Kang Wang Feiyu Diao Zhijun Ye Xinhua Zhang Ertao Zhai Hui Ren Tong Li Hui Wu Yulong He Shirong Cai Jianhui Chen | 2017 | Chinese Journal of Cancer2017，36，9： | 30 |
| 2 | Commelina communis L.: Copper Hyperaccumulator Found in Anhui Province of China显示文摘Commelina communis L. growing over some new copper mining wastelands at Bijiashan, Tongling City of Anhui Province, China, was found to be a copper hyperaccumulator. Its copper concentrations were 2707-6159 (4439±2434) mg kg-1, 369-831 (731±142) mg kg-1, and 429-587 (547±57) mg kg-1, respectively, in the roots, stems, and leaves. The soils supporting the growth of the species had a copper concentration ranging from 4620 to 5020 mg kg-1 and averaging 4835±262 mg kg-1, suggesting that the species could not only grow on heavily copper-contaminated soils but also accumulate extraordinarily high concentration of copper. Thus, it shows great potential in the phytoremediation of copper-contaminated soils,the restoration of mined land, geochemical prospecting, and the study of environmental pollution changes. | TANG SHIRONG HUANG CHANGYONG and ZHU ZUXIANG (Department of Soil Science, College of Environmental Sciences and Natural Resources, Zhejiang Agricultural University, Hangzhou 310029 China) | 1997 | Pedosphere1997，7，3： | 18 |
| 3 | Wavelet neural network based fault diagnosis in nonlinear analog circuits显示文摘The theories of diagnosing nonlinear analog circuits by means of the transient response testing are studied. Wavelet analysis is made to extract the transient response signature of nonlinear circuits and compress the signature dada. The best wavelet function is selected based on the between-category total scatter of signature. The fault dictionary of nonlinear circuits is constructed based on improved back-propagation(BP) neural network. Experimental results demonstrate that the method proposed has high diagnostic sensitivity and fast fault identification and deducibility. | Yin Shirong Chen Guangju Xie Yongle | 2006 | Journal of Systems Engineering and Electronics2006，17，3： | 16 |
| 4 | High-precision relocation of the aftershock sequence of the January 8,2022,M_(S)6.9 Menyuan earthquake显示文摘The 2022 Menyuan M_(S)6.9 earthquake,which occurred on January 8,is the most destructive earthquake to occur near the Lenglongling(LLL)fault since the 2016 Menyuan M_(S)6.4 earthquake.We relocated the mainshock and aftershocks with phase arrival time observations for three days after the mainshock from the Qinghai Seismic Network using the double-difference method.The total length and width of the aftershock sequence are approximately 32 km and 5 km,respectively,and the aftershocks are mainly concentrated at a depth of 7-12 km.The relocated sequence can be divided into 18 km west and 13 km east segments with a boundary approximately 5 km east of the mainshock,where aftershocks are sparse.The east and west fault structures revealed by aftershock locations differ significantly.The west fault strikes EW and inclines to the south at a 71°-90°angle,whereas the east fault strikes 133°and has a smaller dip angle.Elastic strain accumulates at conjunctions of faults with different slip rates where it is prone to large earthquakes.Based on surface traces of faults,the distribution of relocated earthquake sequence and surface ruptures,the mainshock was determined to have occurred at the conjunction of the Tuolaishan(TLS)fault and LLL fault,and the west and east segments of the aftershock sequence were on the TLS fault and LLL fault,respectively.Aftershocks migrate in the early and late stages of the earthquake sequence.In the first 1.5 h after the mainshock,aftershocks expand westward from the mainshock.In the late stage,seismicity on the northeast side of the east fault is higher than that in other regions.The migration rate of the west segment of the aftershock sequence is approximately 4.5 km/decade and the afterslip may exist in the source region. | Liping Fan Boren Li Shirong Liao Ce Jiang Lihua Fang | 2022 | Earthquake Science2022，35，2： | 14 |
| 5 | Application of next-generation sequencing technology to precision medicine in cancer: joint consensus of the Tumor Biomarker Committee of the Chinese Society of Clinical Oncology显示文摘Next-generation sequencing(NGS) technology is capable of sequencing millions or billions of DNA molecules simultaneously.Therefore, it represents a promising tool for the analysis of molecular targets for the initial diagnosis of disease, monitoring of disease progression, and identifying the mechanism of drug resistance. On behalf of the Tumor Biomarker Committee of the Chinese Society of Clinical Oncology(CSCO) and the China Actionable Genome Consortium(CAGC), the present expert group hereby proposes advisory guidelines on clinical applications of NGS technology for the analysis of cancer driver genes for precision cancer therapy. This group comprises an assembly of laboratory cancer geneticists, clinical oncologists, bioinformaticians,pathologists, and other professionals. After multiple rounds of discussions and revisions, the expert group has reached a preliminary consensus on the need of NGS in clinical diagnosis, its regulation, and compliance standards in clinical sample collection. Moreover, it has prepared NGS criteria, the sequencing standard operation procedure(SOP), data analysis, report, and NGS platform certification and validation. | Xuchao Zhang Zhiyong Liang Shengyue Wang Shun Lu Yong Song Ying Cheng Jianming Ying Weiping Liu Yingyong Hou Yangqiu Li Yi Liu Jun Hou Xiufeng Liu Jianyong Shao Yanhong Tai Zheng Wang Li Fu Hui Li Xiaojun Zhou Hua Bai Mengzhao Wang You Lu Jinji Yang Wenzhao Zhong Qing Zhou Xuening Yang Jie Wang Cheng Huang Xiaoqing Liu Xiaoyan Zhou Shirong Zhang Hongxia Tian Yu Chen Ruibao Ren Ning Liao Chunyan Wu Zhongzheng Zhu Hongming Pan Yanhong Gu Liwei Wang Yunpeng Liu Suzhan Zhang Tianshu Liu Gong Chen Zhimin Shao Binghe Xu Qingyuan Zhang Ruihua Xu Lin Shen Yilong Wu | 2019 | Cancer Biology & Medicine2019，16，1： | 14 |
| 6 | Epidermal growth factor receptor (EGFR) T790M mutation identified in plasma indicates failure sites and predicts clinical prognosis in non-small cell lung cancer progression during first-generation tyrosine kinase inhibitor therapy: a prospective observational study显示文摘Introduction:Plasma circulating tumor DNA(ctDNA)is an ideal approach to detecting the epidermal growth factor receptor(EGFR)T790M mutation,which is a major mechanism of resistance to first-generation EGFR-tyrosine kinase inhibitor(TKI)therapy.The present study aimed to explore the association of ctDNA-identified T790M mutation with disease failure sites and clinical prognosis in non-small cell lung cancer(NSCLC)patients.Methods:Patients who progressed on first-generation TKIs were categorized into failure site groups of chest limited(CF),brain limited(BF)and other(OF).Amplification refractory mutation system(ARMS)and droplet digital PCR(ddPCR)were used to identify the T790M mutation in ctDNA.Prognosis was analyzed with Kaplan-Meier methods.Results:Overall concordance between the two methods was 78.3%.According to both ARMS and ddPCR,patients in the OF group had a significantly higher rate of T790M mutation than did patients in the BF and CF groups(P<0.001),and a significantly higher T790M mutation rate was also observed in OF-group patients than in those in the CF and BF groups(P<0.001).AZD9291 was found to be an excellent treatment option and yielded the longest survival for T790M+patients in all groups who had progressed on EGFR-TKIs;for other treatments,the prognosis of T790M−patient subgroups varied.Conclusions:The present study demonstrates that T790M mutation in ctDNA is associated with failure sites for NSCLC patients after EGFR-TKI therapy and indicates that both failure site and T790M mutational status greatly influ-ence treatment selection and prognosis. | Shirong Zhang Lucheng Zhu Bing Xia Enguo Chen Qiong Zhao Xiaochen Zhang Xueqin Chen Xufeng Chen Shenglin Ma | 2018 | Cancer Communications2018，38，1： | 12 |
| 7 | SHRIMP zircon age for a K-bentonite in the top of the Laobao Formation at the Pingyin section,Guizhou,South China显示文摘The Lower Cambrian on the Yangtze Platform in South China(internationally equivalent to the Nerreneuvian and 2nd series of the Cambrian)is valuable for understanding the early evolution of life,the global biogeochemical circles,and the major changes of the ocean.In particular,a precise radiometric calibration of the Lower Cambrian of this region is a critical realm in its multidisciplinary studies.A SHRIMP U-Pb geochronology study of the K-bentonite in the topmost Laobao Formation at the Pingyin section,Guizhou,South China yielded an age of 536±5 Ma(MSWD=0.75),suggesting that the K-bentonite here can be correlated with the intensely studied K-bentonite within the middle Zhongyicun Member(Bed 5)of the Zhujiaqing Formation at the Meishucun section in Yunnan.Such a regional correlation result reveals that the Bed 5 K-bentonite also extends into deeper-water environments rather than being deposited merely in the shallow platform interior of the Yangtze Platform.The age of the K-bentonite at the Pingyin section also implies that its overlying polymetallic Ni-Mo layer should be younger than 536±5 Ma.Hence the previous placement of the Precambrian/Cambrian boundary at this layer is inappropriate.Combined with the results of stratigraphic correlations,it is suggested that the K-bentonites in the middle Zhongyicun Member of the Zhujiaqing Formation(or the equivalents)and the base of the Shiyantou Formation(or its equivalents),together with the polymetallic Ni-Mo layer,serve as three important marker beds.Their self-consistent radiometric ages have established an improved geochronologic framework for the Lower Cambrian in South China. | ZHOU MingZhong LUO TaiYi LIU ShiRong QIAN ZhiKuan XING LeCai | 2013 | Science China Earth Sciences2013，56，10： | 10 |
| 8 | Variation of carbon and nitrogen stoichiometry along a chronosequence of natural temperate forest in northeastern China显示文摘Aims Carbon(C)and nitrogen(N)stoichiometry contributes to under-standing elemental compositions and coupled biogeochemical cycles in ecosystems.However,we know little about the temporal patterns of C:N stoichiometry during forest development.The goal of this study is to explore the temporal patterns of intraspecific and ecosystem components’variations in C:N stoichiometry and the scaling relationships between C and N at different successional stages.Methods Along forest development in a natural temperate forest,northeastern China,four age gradients were categorized into ca.10-,30-,70-and 200-year old,respectively,and three 20 m×20 m plots were set up for each age class.Leaves,branches,fine roots and fresh litter of seven dominant species as well as mineral soil at depth of 0-10 cm were sampled.A Universal CHN Elemental Analyzer was used to determine the C and N concentrations in all samples.Important Findings Intraspecific leaf C,N and C:N ratios remained stable along forest development regardless of tree species;while C,N concentrations and C:N ratios changed significantly either in branches or in fine roots,and they varied with tree species except Populus davidiana(P<0.05).For ecosystem components,we discovered that leaf C:N ratios remained stable when stand age was below ca.70 years and dominant tree species were light-demanding pioneers such as Betula platyphylla and Populus davidiana,while increased signifi-cantly at the age of ca.200 years with Pinus koraiensis as the dom-inant species.C:N ratios in branches and fresh litter did not changed significantly along forest development stages.C concentrations scaled isometrically with respect to N concentrations in mineral soil but not in other ecosystem components.Our results indicate that,leaf has a higher intraspecific C:N stoichiometric stability compared to branch and fine root,whereas for ecosystem components,shifts in species composition mainly affect C:N ratios in leaves rather than other components.This study also demonstrated that C and N remain coupled in mineral soils but not in plant organs or fresh litter during forest development. | Xingyun Liang Shirong Liu Hui Wang Jingxin Wang | 2018 | Journal of Plant Ecology2018，11，3： | 9 |
| 9 | 经皮穴位电刺激联合结肠起搏治疗老年功能性便秘的临床应用显示文摘目的探讨经皮穴位电刺激联合结肠起搏同步协同疗法治疗老年功能性便秘患者的临床疗效。方法根据罗马Ⅳ标准选择118例老年功能性便秘患者,其中治疗组60例,平均年龄(81.45±8.47)岁;对照组58例,平均年龄(79.33±9.31)岁;两组患者在服乳果糖的基础上,治疗组加用经皮穴位(左右天枢及足三里)电刺激联合结肠起搏治疗4周,两组治疗前后均使用便秘患者症状自评量表(PAC-SYM)评分,主要症状评分指标及总分均行分析并行疗效对比。结果治疗组有效率为83.3%,对照组有效率为67.2%,两组治疗前后症状评分均有改善(P<0.05)。说明经皮穴位刺激联合结肠起搏同步协同疗法对老年功能性便秘患者可有效改善症状。两组总有效率对比差异有统计学意义(P<0.05)。结论通过经皮穴位电刺激联合结肠起搏疗法能有效改善老年功能性便秘患者的排便困难症状。 | 邓罡 徐丽姝 陈晋 Shirong Cui | 2020 | 实用医学杂志2020，36，19： | 9 |
| 10 | Olmutinib(HM61713) reversed multidrug resistance by inhibiting the activity of ATPbinding cassette subfamily G member 2 in vitro and in vivo显示文摘Overexpressing of ATP-binding cassette(ABC) transporters is the essential cause of multidrug resistance(MDR), which is a significant hurdle to the success of chemotherapy in many cancers.Therefore, inhibiting the activity of ABC transporters may be a logical approach to circumvent MDR.Olmutinib is an epidermal growth factor receptor(EGFR) tyrosine kinase inhibitor(TKI), which has been approved in South Korea for advanced EGFR T790 M-positive non-small cell lung cancer(NSCLC). Here,we found that olmutinib significantly increased the sensitivity of chemotherapy drug in ABCG2-overexpressing cells. Furthermore, olmutinib could also increase the retention of doxorubicin(DOX) and rhodamine 123(Rho 123) in ABC transporter subfamily G member 2(ABCG2)-overexpressing cells. In addition, olmutinib was found to stimulate ATPase activity and inhibit photolabeling of ABCG2 with [^(125) I]-iodoarylazidoprazosin(IAAP). However, olmutinib neither altered ABCG2 expression at protein and m RNA levels nor blocked EGFR, Her-2 downstream signaling of AKT and ERK. Importantly,olmutinib enhanced the efficacy of topotecan on the inhibition of S1-MI-80 cell xenograft growth. All the results suggest that olmutinib reverses ABCG2-mediated MDR by binding to ATP bind site of ABCG2 and increasing intracellular chemotherapeutic drug accumulation. Our findings encouraged to further clinical investigation on combination therapy of olmutinib with conventional chemotherapeutic drugs in ABCG2-overexpressing cancer patients. | Zhiqiang Zhang Xiaoran Guo Kenneth K.W.To Zhen Chen Xiaona Fang Min Luo Chunling Ma Jianhua Xu Shirong Yan Liwu Fu | 2018 | Acta Pharmaceutica Sinica B2018，8，4： | 9 |
| 11 | Effect of Preparation Methods on Mechanical Properties of PVA/HA Composite Hydrogel显示文摘Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA. | Dekun Zhang~1, Junjie Duan~1, Dagang Wang~2, Shirong Ge~2 1. School of Materials Science and Engineering, China University of Mining and Technology Xuzhou 221116, P. R. China 2. School of Mechanical and Electrical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China | 2010 | Journal of Bionic Engineering2010，7，3： | 8 |
| 12 | Trade-offs and Synergies of Ecosystem Services in Karst Area of China Driven by Grain-for-Green Program显示文摘As an important means regulating the relationship between human and natural ecosystem,ecological restoration program plays a key role in restoring ecosystem functions.The Grain-for-Green Program(GFGP,One of the world’s most ambitious ecosystem conservation set-aside programs aims to transfer farmland on steep slopes to forestland or grassland to increase vegetation coverage)has been widely implemented from 1999 to 2015 and exerted significant influence on land use and ecosystem services(ESs).In this study,three ecological models(In VEST,RUSLE,and CASA)were used to accurately calculate the three key types of ESs,water yield(WY),soil conservation(SC),and net primary production(NPP)in Karst area of southwestern China from 1982 to 2015.The impact of GFGP on ESs and trade-offs was analyzed.It provides practical guidance in carrying out ecological regulation in Karst area of China under global climate change.Results showed that ESs and trade-offs had changed dramatically driven by GFGP.In detail,temporally,SC and NPP exhibited an increasing trend,while WY exhibited a decreasing trend.Spatially,SC basically decreased from west to east;NPP basically increased from north to south;WY basically increased from west to east;NPP and SC,SC and WY developed in the direction of trade-offs driven by the GFGP,while NPP and WY developed in the direction of synergy.Therefore,future ecosystem management and restoration policy-making should consider trade-offs of ESs so as to achieve sustainable provision of ESs. | WANG Xiaofeng ZHANG Xinrong FENG Xiaoming LIU Shirong YIN Lichang CHEN Yongzhe | 2020 | Chinese Geographical Science2020，30，1： | 8 |
| 13 | Sorption of uranyl ions on TiO_2:Effects of pH,contact time,ionic strength,temperature and HA显示文摘Sorption of U(VI) onto TiO_2 as functions of pH, ionic strength, contact time, soil humic acid(SHA), solid-to-liquid ratio and temperature was studied under ambient conditions using batch and spectroscopic approaches. The sorption of U(VI) on TiO_2 was significantly dependent on pH and ionic strength. The presence of SHA slightly enhanced the sorption of U(VI) on TiO_2 below pH 4.0, while it inhibited U(VI) sorption in the higher pH range. U(VI)sorption on TiO_2 was favored at high temperatures, and the sorption process was estimated to be endothermic and spontaneous. Reduction of U(VI) to lower valent species was confirmed by X-ray photo-electron spectroscopy analysis. It is very interesting to find that U(VI) sorption on TiO_2 was promoted in solutions with higher back-ground electrolyte concentrations. In the presence of U(VI), higher back-ground electrolyte made more TiO_2 particles aggregate through(001) facets, leading more(101) facets to be exposed. Therefore, the reduction of U(VI) was enhanced by the exposed(101) facets and more U(VI) removal was observed. | Jingjing Wang Bihong He Xiaoyan Wei Ping Li Jianjun Liang Shirong Qiang Qiaohui Fan Wangsuo Wu | 2019 | Journal of Environmental Sciences2019，31，1： | 7 |
| 14 | Design and application of 60mer oligonucleotide microarray in SARS coronavirus detection显示文摘The 60mer oligonucleotide microarray was designed and applied to detecting of SARS (severe acute respiratory syndrome) coronavirus. Thirty 60mer specific oligos were designed to cover the whole genome of the first submitted coronavirus strain, according to the sequence of TOR2 (GENEBANK Accession: AY274119). These primers were synthesized and printed into a microarray with 12×12 spots. RNAs were extracted from the throat swab and gargling fluid of SARS patients and reverse-transcripted into the double strand cDNAs. The cDNAs were prepared as restricted cDNA fragments by the restriction display (RD) technique and labeled by PCR with the Cy5-universal primer. The labeled samples were then applied to the oligo microarray for hybridization. The diagnostic capability of the microarray was evaluated after the washing and scanning steps. The scanning result showed that samples of SARS patients were hybridized with multiple SARS probes on the microarray, and there is no signal on the negative and blank controls. These results indicate that the genome of SARS coronavirus can be detected in parallel by the 60mer oligonucleotide microarray, which can improve the positive ratio of the diagnosis. The oligo microarray can also be used for monitoring the behavior of the virus genes in different stages of the disease status. | SHIRong MAWenli WUQinghua ZHANGBao SONGYanbin GUOQiuye XIAOWeiwei WANGYan ZHENGWenling | 2003 | Chinese Science Bulletin2003，48，2： | 7 |
| 15 | Cloning and functional characterization of Rht8,a“Green Revolution”replacement gene in wheat显示文摘Dear Editor,Wheat(Triticum aestivum)is a major staple crop in the world and provides~20%of the food calories for human consumption(Appels et al.,2018).During the 1960s and 1970s,the introduction of two semi-dwarfing genes Rht-B1b and Rht-D1b in wheat varieties strikingly improved lodging resistance and harvest index,and therefore substantially increased grain yield,resulting in the well-known'Green Revolution'(Peng et al.,1999).However,plants carrying Rht-B1b and Rht-D1b suffer from several drawbacks. | Hongchun Xiong Chunyun Zhou Meiyu Fu Huijun Guo Yongdun Xie Linshu Zhao Jiayu Gu Shirong Zhao Yuping Ding Yuting Li Jiazi Zhang Ke Wang Xuejun Li Luxiang Liu | 2022 | Molecular Plant2022，15，3： | 7 |
| 16 | Study on Biotribological Behavior of the Combined Joint of CoCrMo and UHMWPE/BHA Composite in a Hip Joint Simulator显示文摘UHMWPE composites reinforced with Bovine Bone Hydroxyapatite(BHA)in different contents were prepared by heatpressing formation method.A hip joint wear simulator was used to investigate the biotribological behavior of UHMWPE/BHAcomposite acetabular cups against CoCrMo alloy femoral heads in bovine synovia lubrication at 37±1 ℃.It was found that theaddition of BHA powder to UHMWPE can improve the hardness and creep modulus of UHMWPE/BHA composites,anddecrease their wear rates under bovine synovia lubrication.When the content of BHA filler particles was up to 30 wt%,UHMWPE/BHA composites demonstrated the well design performances of the surface and biotribological properties.Fatigue,ploughing and slight adhesive wear were the main wear mechanisms for UHMWPE and its composites.In addition,the sizes ofwear particles became larger with an increase in BHA powder addition.These results suggest that BHA filler is a desirablecomponent to increase the wear resistance of UHMWPE/BHA composites for biomedical applications. | Qingliang Wang, Jinlong Liu, Shirong GeCollege of Materials and Engineering, China University of Mining and Technology, Xuzhou 221007, P. R. China | 2009 | Journal of Bionic Engineering2009，6，4： | 6 |
| 17 | Synthesis and Characterization of PVA-HA-Silk Composite Hydrogel by Orthogonal Experiment显示文摘 | Dekun Zhang Kai Chen Lin Wu Dagang Wang Shirong Ge | 2012 | Journal of Bionic Engineering2012，9，2： | 6 |
| 18 | Variations in leaf litter decomposition across contrasting forest stands and controlling factors at local scale显示文摘Aims litter decomposition is a critical pathway linking the above-and belowground processes.However,factors underlying the local spatial variations in forest litter decomposition are still not fully addressed.We investigated leaf litter decomposition across con-trasting forest stands in central China,with objective to determine the spatial variations and controlling factors in forest floor leaf lit-ter decomposition in relation to changes in forest stands in a tem-perate forest ecosystem.Methods leaf litter decomposition was studied by using litterbag method across several typical forest stand types in baotianman Nature reserve,central China,including pure stands of Quercus aliena var.acuteserrata,Q.glandulifera var.brevipetiolata and Q.vari-abilis,respectively,and mixed pine/oak stands dominated by Pinus armandii and Q.aliena var.acuteserrata,as well as stands of pure Q.aliena var.acuteserrata trees ranging in stand age from~40 to>160 years.measurements were made on litter mass remaining and changes in litter chemistry during decomposition over a 2-year period,along with data collections on selective biotic and environmental factors.a reciprocal transplant experiment involv-ing Q.aliena var.acuteserrata and Q.variabilis was concurrently carried out to test the occurrence of‘home-field advantage(HFa)’in local forests when only considering contrasting oak tree spe-cies.Correlation analyses and path analyses were performed to identify the dominant drivers and their relative contributions to variations in leaf litter decomposition.Important findingssignificant variations were found in the rate of leaf litter decomposi-tion among stands of different tree species but not among stand age classes.The values of decay constant,k,varied from 0.62 in Q.aliena var.acuteserrata stands to 0.56 in Q.variabilis stands.The reciprocal litter transplant experiment showed that the rate of leaf litter decom-position was on average 5%slower in home-fields than on recipro-cal sites.Path analysis identified litter acid-unhydrolyzable residue(AUR)to N ratio,soil microbial biomass carbon(MBC),soil pH and soil organic carbon(SOC)as most prominent factors controlling the rate of leaf litter decomposition,collectively accounting for 57.8%of the variations;AUR/N had the greatest negative effect on k value,followed by weaker positive effects of SOC and MBC.our findings suggest that tree species plays a primary role in affecting forest floor leaf litter decomposition by determining the litter quality,with site environment being a secondary factor contributing to the local vari-ations in leaf litter decomposition in this temperate forest ecosystem. | Juan Wang Yeming You Zuoxin Tang Shirong Liu Osbert Jianxin Sun | 2015 | Journal of Plant Ecology2015，8，3： | 6 |
| 19 | CLASSICAL AND HOMOGENIZED EXPRESSIONS FOR BUCKLING SOLUTIONS OF FUNCTIONALLY GRADED MATERIAL LEVINSON BEAMS显示文摘The relationship between the critical buckling loads of functionally graded material(FGM) Levinson beams(LBs) and those of the corresponding homogeneous Euler-Bernoulli beams(HEBBs) is investigated. Properties of the beam are assumed to vary continuously in the depth direction. The governing equations of the FGM beam are derived based on the Levinson beam theory, in which a quadratic variation of the transverse shear strain through the depth is included.By eliminating the axial displacement as well as the rotational angle in the governing equations,an ordinary differential equation in terms of the deflection of the FGM LBs is derived, the form of which is the same as that of HEBBs except for the definition of the load parameter. By solving the eigenvalue problem of ordinary differential equations under different boundary conditions clamped(C), simply-supported(S), roller(R) and free(F) edges combined, a uniform analytical formulation of buckling loads of FGM LBs with S-S, C-C, C-F, C-R and S-R edges is presented for those of HEBBs with the same boundary conditions. For the C-S beam the above-mentioned equation does not hold. Instead, a transcendental equation is derived to find the critical buckling load for the FGM LB which is similar to that for HEBB with the same ends. The significance of this work lies in that the solution of the critical buckling load of a FGM LB can be reduced to that of the HEBB and calculation of three constants whose values only depend upon the throughthe-depth gradient of the material properties and the geometry of the beam. So, a homogeneous and classical expression for the buckling solution of FGM LBs is accomplished. | Shirong Li Xuan Wang Zeqing Wan | 2015 | Acta Mechanica Solida Sinica2015，28，5： | 6 |
| 20 | Free vibration analysis of functionally graded material beams based on Levinson beam theory显示文摘Free vibration response of functionally graded material(FGM) beams is studied based on the Levinson beam theory(LBT). Equations of motion of an FGM beam are derived by directly integrating the stress-form equations of elasticity along the beam depth with the inertial resultant forces related to the included coupling and higherorder shear strain. Assuming harmonic response, governing equations of the free vibration of the FGM beam are reduced to a standard system of second-order ordinary differential equations associated with boundary conditions in terms of shape functions related to axial and transverse displacements and the rotational angle. By a shooting method to solve the two-point boundary value problem of the three coupled ordinary differential equations,free vibration response of thick FGM beams is obtained numerically. Particularly, for a beam with simply supported edges, the natural frequency of an FGM Levinson beam is analytically derived in terms of the natural frequency of a corresponding homogenous Euler-Bernoulli beam. As the material properties are assumed to vary through the depth according to the power-law functions, the numerical results of frequencies are presented to examine the effects of the material gradient parameter, the length-to-depth ratio, and the boundary conditions on the vibration response. | Xuan WANG Shirong LI | 2016 | Applied Mathematics and Mechanics(English Edition)2016，37，7： | 6 |
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