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Success factors for high-quality oak forest(Quercus robur, Q. petraea) regeneration

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Forest Ecosystems 2019年第4期6卷 367-383页

作者： Andreas M?lder Holger Sennhenn-Reulen Christoph Fischer Hendrik Rumpf Egbert Sch?nfelder Johannes Stockmann Ralf-Volker Nagel Department A (Forest Growth) Northwest German Forest Research Institute(NW-FVA)

Background: Within the framework of close-to-nature forestry, oak forest(Quercus robur, Q. petraea) regeneration techniques that consider both silvicultural and nature conservation demands have become a very important *** there are many experimental and local studies that aim at disentangling the relationships between different environmental and silvicultural factors and the success of oak regeneration, systematic supra-regional studies at the greater landscape level are missing so *** this background, the first objective(a) of this study was to present an efficient and sufficiently accurate sampling scheme for supra-regional forest regrowth inventories, which we applied to young oaks stands. The second, and major, objective(b) was to identify the crucial success factors for high-quality oak forest regeneration in northwest ***: Objective(a): Factors that have been identified as potentially crucial for the success or failure of oak regeneration were either included in a field inventory procedure or extracted from forest inventory databases. We found that the collected data were suitable to be analyzed in a three-step success model, which was aimed at identifying the crucial success factors for high-quality oak forest ***(b): Our modeling procedure, which included a Bayesian estimation approach with spike-and-slab priors,revealed that competitive pressure from the secondary tree species was the most decisive success factor;no competition, or low competition by secondary tree species appeared to be particularly beneficial for the success of high-quality oak regeneration. Also fencing and the absence of competitive vegetation(weeds, grass, bracken)seemed to be beneficial factors for the success of oak ***: Trusting in biological automation was found to be mostly useless regarding economically viable oak forest regeneration. To efficiently organize oak regeneration planning and silvicultural decision-ma

关键词： Close-to-nature forestry Competition Ecological continuity Forest inventory Forest management Plantplant interactions Quercus robur Quercus petraea Regeneration Silviculture

Simulation of rainfall-runoff and watershed convergence process in the upper reaches of Heihe River Basin,July 2002

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Science China Earth Sciences 2004年第z1期47卷 1-8页

作者： GAO Yanhong L(U) Shihua CHENG Guodong Cold and Arid Regions Environmental and Engineering research institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The watershed flow concentration scheme in the distributed hydrology-soil- vegetation model (DHSVM) is coupled with the mesoscale atmospheric model MM5 version 3.5, in which the Oregen States University land surface model (OSULSM) was involved. The flood event which happened in July 2002 in the upper reaches of Heihe river basin is simulated and the surface flow convergence process is shown with this coupled model. It has been concluded that times water head reaches each place of the basin are different. Water amount at each point is split-flow proportionally as the drops in elevation between it and neighbor points. Large part of the water amount pass away in greater slope direction and small part pass away in smaller slope *** of the slope convergence makes the atmospheric model redistributes the surface water laterally.

关键词： distributed hydrology-soil-vegetation model, mesoscale atmospheric model, watershed flow concentration process.

Pattern Classification of Enterovirus 71-Associated Hand, Foot, and Mouth Disease in Chinese Medicine: A Retrospective Study in 433 Cases

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Chinese Journal of Integrative Medicine 2018年第2期24卷 87-93页

作者： LIU Yan HE Li-yun WEN Tian-cai YAN Shi-yan BAI Wen-jing LIU Bao-yan institute of Basic research in Clinical Medicine China Academy of Chinese Medical Sciences

Objective： To determine whether patterns of enterovirus 71（EV71）-associated hand, foot, and mouth disease（HFMD） were classified based on symptoms and signs, and explore whether individual characteristics were correlated with membership in particular pattern. Methods： Symptom-based latent class analysis（LCA） was used to determine whether patterns of EV71-HFMD existed in a sample of 433 cases from a clinical data warehouse system. Logistic regression was then performed to explore whether demographic, and laboratory data were associated with pattern membership. Results： LCA demonstrated a two-subgroup solution with an optimal fit, deduced according to the Bayesian Information Criterion minima. Hot pattern（59.1% of all patients） was characterized by a very high fever and high endorsement rates for classical HFMD symptoms（i.e., rash on the extremities, blisters, and oral mucosa lesions）. Non-hot pattern（40.9% of all patients） was characterized by classical HFMD symptoms. The multiple logistic regression results suggest that white blood cell counts and aspartate transaminase were positively correlated with the hot pattern（adjust odds ratio=1.07, 95% confidence interval： 1.006–1.115; adjust odds ratio=1.051, 95% confidence interval： 1.019–1.084; respectively）. Conclusions： LCA on reported symptoms and signs in a retrospective study allowed different subgroups with meaningful clinical correlates to be defined. These findings provide evidence for targeted prevention and treatment interventions.

关键词： hand foot and mouth disease pattern classification enterovirus A human Chinese medicine

The Aging Behavior of Polyurethane Adhesive in Medium

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 892-895页

作者：倪晓雪 University of Science and Technology Beijing Wuhan research institute of Materials Protection

The aging behavior of polyurethane adhesive in medium was investigated and compared by means of scanning electronic microscopy（SEM）, infrared spectroscopy（IR）, interface analysis and shearing strength test. The experimental results show that the shear strength of polyurethane adhesive in salt water is decreased more quickly than that in water. Na^＋ and Cl^- ions could make the polyurethane adhesive age faster and the interface metal corrosion. The high temperature accelerates the diffusion of water molecule, Na^＋ and Cl^- ions and the degradation of the giant molecule.

关键词： polyurethane adhesive medium aging shear strength

Experimental and Theoretical Study on Bonding Properties between Steel Bar and Bamboo Scrimber

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Journal of Renewable Materials 2020年第7期8卷 773-787页

作者： Xiangya Luo Haiqing Ren Yong Zhong research institute of Wood Industry Chinese Academy of ForestryBeijing100714China

To further verify the feasibility of newly designed reinforced bamboo scrimber composite(RBSC)beams used in building construction,the bonding properties between steel bar and bamboo scrimber were investigated by anti-pulling *** indicated that the anti-pulling mechanical properties were significantly correlated to the diameter,thread form and buried depth of steel bar,forming density of bamboo scrimber as well as the heat treatment of bamboo *** were two failure modes for anti-pulling tests:the tensile fracture and pulling out of steel *** the ultimate load and average shear strength of anti-pulling specimen could be increased greatly with the ribbed bar,high forming density of bamboo scrimber and un-heated bamboo ***,a theoretical calculation model of the bonding interface between steel bar and bamboo scrimber was *** on the theoretical calculation model,the change laws of normal stress of bamboo scrimber,and shear stress of glue layer along the buried depth of steel bar were *** study is beneficial for the safety application of RBSC beams in building construction.

关键词： Reinforced bamboo scrimber composite(RBSC) bonding properties anti-pulling tests theoretical calculation model

Impact of the Spring SST Gradient between the Tropical Indian Ocean and Western Pacific on Landfalling Tropical Cyclone Frequency in China

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Advances in Atmospheric Sciences 2018年第6期35卷 682-688页

作者： Lei WANG Guanghua CHEN Center for Monsoon System research Institute of Atmospheric Physics Chinese Academy of Sciences

The present study identifies a significant influence of the sea surface temperature gradient（SSTG） between the tropical Indian Ocean（TIO; 15°S-15°N, 40°-90°E） and the western Pacific warm pool（WWP; 0°-15°N, 125°-155°E） in boreal spring on tropical cyclone（TC） landfall frequency in China's Mainland in boreal summer. During the period 1979-2015, a positive spring SSTG induces a zonal inter-basin circulation anomaly with lower-level convergence, mid-tropospheric ascendance and upper-level divergence over the west-central TIO, and the opposite situation over the WWP, which produces lower-level anomalous easterlies and upper-level anomalous westerlies between the TIO and WWP. This zonal circulation anomaly further warms the west-central TIO by driving warm water westward and cools the WWP by inducing local upwelling, which facilitates the persistence of the anomaly until the summer. Consequently, lower-level negative vorticity, strong vertical wind shear and lower-level anticyclonic anomalies prevail over most of the western North Pacific（WNP）, which decreases the TC genesis frequency. Meanwhile, there is an anomalous mid-tropospheric anticyclone over the main WNP TC genesis region,meaning a westerly anomaly dominates over coastal regions of China's Mainland, which is unfavorable for steering TCs to make landfall in China's Mainland during summer. This implies that the spring SSTG may act as a potential indicator for TC landfall frequency in China's Mainland.

关键词： tropical cyclone landfall sea surface temperature gradient air-sea interaction

Patch nearfield acoustic holography based on the equivalent source method

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Science China(Technological Sciences) 2008年第1期51卷 100-110页

作者： BI ChuanXing CHEN XinZhao XU Liang CHEN Jian institute of Sound and Vibration research Hefei University of TechnologyHefei 230009China

On the basis of nearfield acoustic holography (NAH) based on the equivalent source method (ESM), patch NAH based on the ESM is proposed. The method overcomes the shortcoming in the conventional NAH that the hologram surface should be larger than the source surface. It need not to discretize the whole source and its measurement need not to cover the whole source. The measurement may be performed over the region of interest, and the reconstruction can be done in the region directly. The method is flexible in applications, stable in computation, and very easy to implement. It has good potential applications in engineering. The nu- merical simulations show the invalidity of the conventional NAH based on the ESM and prove the validities of the proposed method for reconstructing a partial source and the regularization for reducing the error effect of the pressure measured on the hologram surface.

关键词： acoustic holography near field equivalent source regularization

Characterization of the proteases in the midgut of the xylophagous larvae of Oemona hirta （Coleoptera： Cerambycidae）

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Insect Science 2009年第5期16卷 381-386页

作者： Brian David Shaw John Tane Christeller The New Zealand institute of Plant and Food research Palmerston North New Zealand

The protein digestive capability of the larvae of the longhorn beetle （Oemona hirta, Coleoptera： Cerambycidae, Fabricius, 1775） was investigated. This species feeds only on wood where there is a high proportion of vascular tissue. The pH of the midgut, the major digestive organ, was alkaline and protein hydrolysis was maximal at alkaline pH. Use of specific synthetic peptide substrates showed that the major protease activities were the endopeptidases, trypsin and chymotrypsin-like activity, and the exopeptidase, leucine aminopeptidase and the pH curves corresponded to that with protein substrate. Studies using a range ofserine protease inhibitors as well as specific inhibitors ofmetalloproteases, cysteine proteases and aspartate proteases confirmed a serine protease-based digestive system similar to earlier reports of sapwood-feeding Cerambycids. Control of these insect pests using protease inhibitors is discussed.

关键词： chymotrypsin digestion Oemona hirta trypsin xylophagy

Yb:CaF_(2)-YF_(3)transparent ceramics ultrafast laser at dual gain lines

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Chinese Physics B 2022年第11期31卷 336-340页

作者： Xiao-Qin Liu Qian-Qian Hao Jie Liu Dan-Hua Liu Wei-Wei Li Liang-Bi Su Shandong Provincial Key Laboratory of Optics and Photonic Device School of Physics and ElectronicsShandong Normal UniversityJinan 250358China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China State Key Laboratory of High Performance ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Yb^(3+):CaF_(2)–YF_(3)transparent ceramics with excellent optical quality was successfully fabricated by hot-pressed *** laser properties of this ceramics were investigated for the first *** diode(LD)was applied as the pump source to generate a dual-wavelength mode-locked(ML)*** maximum average output power was 310 mW,which represents the highest output power of ultrafast calcium fluoride ceramic *** spectrum separated at 1048.9 nm and 1049.7 nm with a total pulse duration of 8.9 *** interval period between the beating signals was about 4.3 ps,corresponding to a 0.23 THz beat pulse repetition *** results demonstrate its potential in producing dual-wavelength ultrashort *** Yb^(3+):CaF_(2)–YF_(3)ceramics with low-cost and short-preparation period are ideal candidate materials for ultrafast lasers.

关键词： transparent ceramics passively mode-locking dual-wavelength laser