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Summer Monsoon Rainfall Variability in Central China over the Past 4700 Years and Its Possible Link to Solar Activity

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Journal of Meteorological Research 2021年第4期35卷 594-606页

作者： Jingwei ZHANG Kan ZHAO Xinggong KONG Yongjin wang Xianfang wang Shushuang LIU Zhenjun wang Hai cheng R.Lawrence EDWARDS School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China School of Geography Science Nanjing Normal UniversityNanjing 210023China Key Laboratory ofPoyang LakeWetland and Watershed Research of Ministry of Education Jiangxi Normal UniversityNanchang 330022China Lanling NO.4 Middle School Linyi 277700China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049China Department of Geology and Geophysics University of MinnesotaMinneapolis MN55455USA

Based on 467 pairs ofδ^(18)O andδ^(13)C records and 8230 Th dates from a stalagmite(BF4)from Xiniu Cave,central China,we present a reconstruction of 9-yr resolution monsoon rainfall record for the past 4700 ***δ^(18)O record shows good coherence with East Asian summer monsoon(EASM)rainfall proxies from adjacent regions during the overlapping intervals,suggesting thatδ^(18)O signal in BF4 can be interpreted as a monsoon rainfall ***δ^(13) C variations are related to changes in local processes at the cave site,and regional rainfall and temperature *** on theδ18 O record,a series of dry periods can be identified at 4500-4200,3500-3200,2800-2500,1900-1600,1400-1200,700-500,and 400-200 yr BP,while a series of wet periods can be identified at 4200-3600,2400-2200,3200-2800,1100-900,600-400,and 200-100 yr *** spectrum analysis on ourδ^(18) O record reveals significant cycles at 470 and 80 yr,coinciding with the typical solar periodic *** result suggests that changes in solar activity play a dominant role in driving centennial-decadal monsoon rainfall variation in central *** to minor changes in solar irradiance(less than 1.5 W m^(-2))over the past 4700 years,our record was further compared to the El Nino-Southern Oscillation(ENSO)and Pacific Decadal Oscillation(PDO)proxies,confirming that solar forcing on monsoon rainfall changes might be amplified by the ENSO and PDO *** 600 to 150 yr BP(the Little Ice Age,LIA),a positive shift of 2‰can be revealed in both theδ^(18)O andδ^(13)C records,indicating a cold/dry climatic *** comparing ourδ^(18)O andδ^(13)C records with historical documents,we suggest that the climatic deteriorations between 450 and 250 yr BP may have caused serious social unrest at the end of the Ming Dynasty.

关键词： stalagmite record Xiniu Cave solar activity El Nino-Southern Oscillation(ENSO) Pacific Decadal Oscillation(PDO) amplify mechanism Little Ice Age(LIA)

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Clinical outcomes with large macular holes using the tiled transplantation internal limiting membrane pedicle flap technique

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International Journal of Ophthalmology(English edition) 2019年第2期12卷 246-251页

作者： Li-ping wang Wen-Tao Sun Chun-Ling Lei Jin Deng Department of Ophthalmology Shaanxi Ophthalmic Medical Center Xi'an Fourth Hospital Affiliated Guangren HospitalSchool of Medicine Xi'an Jiaotong University

AIM: To report the surgical technique and efficacy of the tiled transplantation internal limiting membrane(ILM) pedicle flap technique after vitrectomy for 33 patients with large macular hole(MH). METHODS: This study was a prospective noncontrolled interventional study. All patients were treated by vitrectomy, the tiled transplantation ILM pedicle flap and gas tamponade. All patients underwent visual acuity measurements and optical coherence tomography(OCT), during preoperative and the follow-up visits postoperative. RESULTS: Two high-myopic patient had flap dislocation during surgery. The thorough closure of MH following the tiled transplantation ILM pedicle flap technique was ultimately achieved in 31 patients observed by OCT imaging(93.94%) 1 wk after surgery. Visual acuity improved from 1.51±0.31(logMAR) preoperative to 0.92±0.30 6 mo after surgery(P=0.000). There were no significant changes in OCT finding during the follow-up period from 1 mo to 6 mo after surgery. CONCLUSION: The tiled transplantation ILM pedicle flap technique provides bridge for retinal gliosis to achieve successful closures of the large MHs, and the microenvironment of this technique is more similar to the normal physiological conditions.

关键词： tiled transplantation ILM pedicle flap macular hole vitrectomy

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Cloning,sequencing and expression analysis of the NAR promoter activated during hyphal stage of Magnaporthe grisea

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第9期8卷 661-665页

作者： LU Jian-ping DUAN Zhi-bing LIU Tong-bao LIN Fu-cheng Department of Biology School of Life Sciences Zhejiang University Hangzhou 310058 China Biotechnology Institute Zhejiang University Hangzhou 310029 China

The promoter of NAR gene in Magnaporthe grisea was isolated and sequenced. The promoter sequences contained the "TATA" box, the "CAAT" box, and binding sites for fungal regulatory proteins. Programs that predict promoter sequences in-dicated that promoter sequence lies between locations 430 and 857 of the NAR promoter fragment. GFP expression under the NAR promoter and NAR transcript analysis revealed that this promoter is activated primarily at the mycelial stage in the rice blast fungus and could be used to express native or extrinsic genes in the mycelia of the rice blast fungus.

关键词： Magnaporthe grisea Promoter NAR Clone Hypha

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Effects of forced cooling on mechanical properties and fracture behavior of heavy section ductile iron

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China Foundry 2015年第6期12卷 398-405页

作者： Er-jun Guo Liang Song Li-ping wang Dong-rong Liu School of Materials Science and Engineering Harbin University of Science and Technology School of Materials Science and Engineering Heilongjiang University of Science and Technology

To develop materials suitable for spent-nuclear-fuel containers, the effect of forced cooling on mechanical properties and fracture toughness of heavy section ductile iron was investigated. Two cubic castings with different cooling processes were prepared: casting A was prepared in a totally sand mold, and casting B was prepared in a sand mold with two chilling blocks placed on the left and right sides of the mold. Three positions in each casting with different solidification cooling rates were chosen. In-situ SEM tensile experiment was used to observe the dynamic tensile process. Fracture analysis was conducted to study the influence of vermicular and slightly irregular spheroidal graphite on the fracture behavior of heavy section ductile iron. Results show that the tensile strength, elongation, impact toughness and fracture toughness at different positions of the two castings all decrease with decreasing cooling rate. With the increase of solidification time, the fracture mechanism of conventional casting A changes from ductile fracture to brittle fracture, and that of casting B with forced cooling changes from ductile fracture to a mixture of ductile-brittle fracture.

关键词： heavy section ductile iron forced cooling in-situ SEM tensile fracture toughness

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Origin and genetic family of Huhehu oil in the Hailar Basin, northeast China

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Acta Geochimica 2018年第6期37卷 820-841页

作者： Yao-ping wang Fan Zhang Yan-Rong Zou Zhao-Wen Zhan Yulan Cai State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou510640People's Republic of China University of Chinese Academy of Sciences Beijing100049People's Republic of China Exploration and Development Research Institute of Daqing Oilfield PetroChinaDaqing163712People's Republic of China

The Huhehu Sag is one of the most important oil and gas depressions in the Hailar Basin. However, the origin of Huhehu oil is still controversial. Previous studies on source rocks have mainly focused on the Nantun Formation(K1 n); a few studies have investigated the Damoguaihe Formation(K1 d). Based on the Rock–Eval pyrolysis parameters, 172 drill cutting samples from the Huhehu Sag were analyzed to evaluate their geochemical characteristics. Based on the Rock–Eval data, the mudstones from the first member of the Damoguaihe Formation(K1 d1) and the second member of the Nantun Formation(K1 n2) have moderate to high hydrocarbon generation potential, while mudstones from the first member of the Nantun Formation(K1 n1) have poor to good hydrocarbon generation ***, both the K1 n1 and K1 n2 coal members have poor to fair hydrocarbon generation potential, but the K1 n2 coal member has a better generative potential. Fifteen Huhehu oils were collected for molecular geochemical analyses to classify the oils into genetic families and to identify the source rock for each oil using chemometric methods. The Huhehu oils were classified into three groups with different maturity levels using hierarchical cluster analysis and principal component analysis. Group A oils(high maturity) are characterized by relatively moderate ratios of Pr/Ph, Pr/n-C17, and Ph/n-C18, as well as an abundance of C29 steranes, mainly derived from the K1 n2 and K1 n1 mudstone members. In comparison, group B oils(moderate maturity) have relatively low Pr/Ph ratios,moderate Pr/n-C17 and Ph/n-C18 ratios, and low concentrations of C29 steranes. Group C oils(low maturity) show relatively high ratios of Pr/Ph, Pr/n-C17, and Ph/n-C18, as well as high concentrations of C29 steranes. Furthermore,group B oils derived from the K1 d1 mudstone member and group C oils derived from the K1 n2 coal member were also identified by principal component analysis score *** studies suggest a major c

关键词： Hailar Basin Huhehu Sag Biomarkers Chemometrics Oil–oil and oil–source rock correlations

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Intensive peatland wildfires during the Aptian-Albian oceanic anoxic event 1b:Evidence from borehole SK-2 in the Songliao Basin,NE China

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Journal of Palaeogeography 2022年第3期11卷 448-467页

作者： Zhi-Hui Zhang Da-Wei Lü Tian-Tian wang Dong-Zhao An Hai-Yan Liu Dong-Dong wang cheng-Shan wang Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina Institute of Earth Sciences China University of GeosciencesBeijing 100083China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Chinese Academy of Geological Sciences Beijing 100037China

The Cretaceous has been considered a“high-fire”world accompanied by widespread by-products of combustion in the rock *** mid-Cretaceous oceanic anoxic event 1b(OAE1b)is marked by one of the major perturbations in the global carbon cycle characterized by deposition of organic-rich sediments in both marine and terrestrial ***,our understanding is still limited on changes in wildfire activity during OAE1b ***,we carried out a comprehensive analysis,including organic carbon isotope(δ^(13)C_(org)),total organic carbon(TOC),coal petrology,trace elements,and pyrolytic polycyclic aromatic hydrocarbons(pyroPAHs),of coal seams of the middle Aptian to early Albian Shahezi Formation from borehole SK-2 in Songliao Basin,Northeast *** negativeδ^(13)C_(org) excursions in the Shahezi Formation can be corresponded with the 113/Jacob and Kilian sub-events of ***,the intensive peatland wildfires have been identified during the sub-event periods of OAE1b based on the co-occurrence of high abundance of charcoal and pyroPAHs at that *** addition,Sr/Ba,Sr/Cu and Sr/Rb ratios demonstrate that enhanced peatland wildfires were controlled by dryer climate conditions owing to episodic northward migration of arid zones in East Asia related with rising global temperature during the sub-events of *** climate-driven extensive wildfire activity in the mid-latitude terrestrial ecosystems can be a contributing factor for OAE1b through the increased flux of nutrients fuelling primary producers in the lake and marine environments and leading to more speculative anoxia to allow the deposition of organic-rich *** results provide essential understanding of the importance of wildfires in driving mechanism of oceanic anoxic events(OAEs)in Earth's history.

关键词： Lower Cretaceous OAEs Peatland Wildfire Coals

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Influence of composition and size on the thermodynamic stability and structural evolution of CuAlNi nanoclusters

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Progress in Natural Science:Materials International 2020年第4期30卷 477-484页

作者： Qing Liu Ye Su Keke Song Xiaoxu wang Panpan Gao Chutian wang Yuqin Xiao Xiaodong Jian ping Qian Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interfere Science School of Mathematics and Physics University of Science and Technology Beijing National Supercomputer Center in Tianjin

The heating process for CuAlNi nanoclusters with cuboctahedral structure was studied by molecular dynamics simulation with the embedded atom method. A diffusionless martensitic transformation from the cuboctahedral(CO) to the icosahedral(ICO) structure before the melting point was found in some CuAlNi nanoclusters. The effects of element composition and cluster size on the thermodynamic stability and structural transformation of trimetallic nanoclusters were investigated. The results show that the CO–ICO transformation temperature was size-dependent and occurred only for small clusters. It was also observed that the CO–ICO transformation temperature firstly dropped and then raised as Al concentration increased, which may be strongly related to the release of excess energy. Furthermore, the surface segregation phenomenon was also observed that the lower surface energy components, such as Al and Cu atoms, segregated to the surface of CuAlNi nanoclusters. The changes in the melting points of Cu Al Ni nanoclusters with different alloy compositions and cluster sizes were also studied. And furthermore, the physical basis of structural transition of CuAlNi nanoclusters was discussed.

关键词： MD simulation Structural transformation Thermodynamic stability Alloy nanocluster Size effect

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Change in Spring Meridional Circulation and Its Relation to Summer Typhoon Activities

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Atmospheric and Oceanic Science Letters 2013年第3期6卷 144-148页

作者： CHEN Dong wang Hui-Jun LI Guo-ping College of Atmospheric Sciences Chengdu University of Information Technology Graduate University of Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of Sciences

This study documents the decadal changes of the spring meridional circulation （SMC） over 110°E- 165°E and the relationship between the SMC and summer （June-July-August-September） typhoon activity over the Western North Pacific （WNP） during 1948-2010. The authors found that the SMC was changed after 1969. Before its change, the SMC had no clear relation with the summer typhoon number over the WNP （TNWNP）, but after the change, it has become positively correlated with the TNWNP, with a correlation coefficient of 0.57 be- tween them （above the 99% confidence level）. It was ob- served that after the SMC was changed, the positive tropical sea surface temperature anomaly associated with the SMC was shifted from the Equatorial Eastern Pacific （El Nifio） to the equatorial middle Pacific （El Nifio Mo- doki）; at the same time, the Pacific decadal oscillation （PDO） pattern over the North Pacific, which is associated with the SMC, was enhanced. The SMC and the TNWNP are both modulated by the E1 Nifio Modoki after 1969, so the relationship between them becomes significant.

关键词： spring meridional circulation summer tynhnon activity Modoki.

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Predicted Robustness as QoS for Deep Neural Network Models

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Journal of Computer Science & Technology 2020年第5期35卷 999-1015页

作者： Yue-Huan wang Ze-Nan Li Jing-Wei Xu ping Yu Taolue Chen Xiao-Xing Ma State Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210023China Department of Computer Science University of SurreyGuilfordGU27XHU.K.

The adoption of deep neural network(DNN)model as the integral part of real-world software systems necessitates explicit consideration of their quality-of-service(QoS).It is well-known that DNN models are prone to adversarial attacks,and thus it is vitally important to be aware of how robust a modeFs prediction is for a given input instance.A fragile prediction,even with high confidence,is not trustworthy in light of the possibility of adversarial *** propose that DNN models should produce a robustness value as an additional QoS indicator,along with the confidence value,for each prediction they *** approaches for robustness computation are based on adversarial searching,which are usually too expensive to be excised in real *** this paper,we propose to predict,rather than to compute,the robustness measure for each input ***,our approach inspects the output of the neurons of the target model and trains another DNN model to predict the *** focus on convolutional neural network(CNN)models in the current *** show that our approach is accurate,with only 10%-34%additional errors compared with the offline heavy-weight robustness *** also significantly outperforms some alternative *** further validate the effectiveness of the approach when it is applied to detect adversarial attacks and out-of-distribution *** approach demonstrates a better performance than,or at least is comparable to,the state-of-the-art techniques.

关键词： deep neural network quality of service robustness prediction

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A novel cytotoxic neophysalin from Physalis alkekengi ***

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Chinese Chemical Letters 2009年第11期20卷 1327-1330页

作者： Chu Hang Zhang Zheng Tao wang Yi ping Yang Qi Shi Sun School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Key Laboratory of Standardization of Chinese Medicines of Ministry of Education Institute of Chinese Materia Medica Shanghai University of Traditional Chinese Medicine Shanghai 201203 China

A new neophysalin, named 5α-hydroxy-25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A（1）, along with three other known neophysalins （2-4） were isolated from the calyxes of Physalis alkekengi L. *** （Mast.） Makino. The structure of 1 was determined by means of 1D and 2D NMR, UV, IR and mass spectra. Compound 1 displayed potent cytotoxicities in vitro against PC- 3 and LNCaP cell lines.

关键词： Physalis alkekengi var. francheti Neophysalin Cytotoxicity

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