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3种天然阔叶混交林林木物种和大小分化多样性与地形的耦合关系

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东北林业大学学报 2025年第2期53卷 16-24页

作者：郜昌建王海龙徐森张小伟浙江省林业勘测规划设计有限公司杭州310020 浙江省森林资源监测中心

依据2021年浙江省森林资源连续清查数据,选取969个幼龄林和中林龄天然阔叶混交林样地,并依据样地植被型将样地划分为常绿阔叶林、落叶阔叶林和常绿落叶阔叶3种植被类型,采用方差分析及Pearson分析地形与林木物种和大小分化多样性的关系... 详细信息

依据2021年浙江省森林资源连续清查数据,选取969个幼龄林和中林龄天然阔叶混交林样地,并依据样地植被型将样地划分为常绿阔叶林、落叶阔叶林和常绿落叶阔叶3种植被类型,采用方差分析及Pearson分析地形与林木物种和大小分化多样性的关系。结果表明:1)3种植被类型间物种多样性指标间均呈显著差异(P<0.05),落叶阔叶林胸径变异系数和胸径均匀度显著高于常绿阔叶林(P<0.05),而常绿阔叶林胸径香农维纳指数显著高于落叶阔叶林和常绿落叶阔叶林(P<0.05);2)随海拔或坡度的升高,3种植被类型丰富度、香农维纳指数和辛普森多样性指数均显著升高(P<0.05),但落叶阔叶林和常绿落叶阔叶林Pielou均匀度指数无明显差异,坡向对林木物种多样性无明显影响;3)随海拔升高,3种植被类型胸径变异系数和胸径均匀度整体上均呈降低趋势,而胸径香农维纳指数则相反;由阳坡到阴坡,常绿阔叶林和常绿落叶阔叶林胸径均匀度指数整体上均呈升高趋势;随坡度增加,落叶阔叶林胸径变异系数和3种植被类型胸径均匀度均降低,而落叶阔叶林胸径香农维纳指数则相反。海拔和坡度对3种植被类型树种数量、胸径均匀度有明显影响,但对落叶阔叶林和常绿落叶阔叶林树种均匀度、常绿阔叶林胸径变异系数均无明显影响,而坡向主要影响常绿阔叶林和常绿落叶阔叶林胸径均匀度。

关键词：天然阔叶混交林地形物种多样性大小分化多样性

Synthesis and Microphase Separation Behavior of Random, Mixed Cylindrical Brush Copolymers Bearing Polystyrene and Poly(ε-caprolactone) Side Chains

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Chinese Journal of Polymer Science 2017年第12期35卷 1572-1586页

作者： Houluo Cong sen xu 郑思珣 Department of Polymer Science and Engineering and the State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University

A series of mixed, random cylindrical brush copolymers bearing polystyrene（PS） and poly（ε-caprolactone）（PCL） side chains were synthesized via the combination of ring-opening polymerization（ROP） and atom transfer radical polymerization（ATRP）. These novel cylindrical brush copolymers have been characterized by means of nuclear magnetic resonance（NMR） spectroscopy, gel permeation chromatography（GPC） and differential scanning calorimetry（DSC）. It was found that the mikto-armed cylindrical brush copolymers were microphase-separated in bulks and that the morphologies were dependent on the mass ratios of PS to PCL side chains. One of the cylindrical brush copolymers was employed to incorporate into epoxy thermoset to investigate effect of the mikto-armed cylindrical brush architecture on the reaction-induced microphase separation behavior. Depending on the concentration of the cylindrical brush in epoxy, the thermosets can display the morphologies with the spherical, worm-like and lamellar PS microdomains dispersing in continuous thermosetting matrices.

关键词： Cylindrical brush copolymers Block copolyrner Epoxy Reaction-induced microphase separation

Experimental research on charging characteristics of a pressure-controlled VRLA battery in high-temperature environments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 418-422页

作者： Hua ZHU Jin-jun TAN Zhang-lu xu Ji-sen xu Institute of Thermal Science and Power Systems Zhejiang University Hangzhou 310027 China

Valve-regulated-lead-acid (VRLA) battery charging performed in high-temperature environments is extremely risky under overcharge conditions, and may lead to a subsequent thermal runaway. A new pressure-controlled charging method was adopted and the charging characteristics of the pressure-controlled VRLA battery in high-temperature environments were ex-perimentally studied. The concept was tested in a large temperature gradient to obtain more details about the effects of users' accustomed charging and discharging modes on battery capacity. The premature capacity loss (PCL) phenomenon under high temperature exposure was analyzed. The results showed that the capacity loss could be recovered by charging using a large current.

关键词： Valve-regulated-lead-acid (VRLA) battery Pressure-controlled charging method High-temperature environments Charging and discharging characteristics

Formation of Poly(ε-caprolactone) Networks via Supramolecular Hydrogen Bonding Interactions

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Chinese Journal of Polymer Science 2019年第3期37卷 197-207页

作者： sen xu Pengfei Chang Bingjie Zhao Muhammad Adeel Sixun Zheng Department of Polymer Science and Engineering and the State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University

In this contribution, we reported a novel approach to crosslink poly(ε-caprolactone)(PCL) via supramolecular hydrogen bonding interactions. First, a series of octa-armed poly(ε-caprolactone) stars with polyhedral oligomeric silsesquioxane(POSS) cores were synthesized via the ring-opening polymerizations. Thereafter, the arm ends of organic-inorganic star-shaped PCLs were reacted with 2-(6-isocyanatohexylaminocarbonylamino)-6-methyl-4[1 H]-pyrimidinone to obtain 2-ureido-4[1 H]-pyrimidone(UPy)-terminated PCL ***, the UPy-terminated PCL stars were physically crosslinked, which was evidenced by means of dynamic mechanical thermal analysis(DMTA) and rheological analysis. Owing to the formation of the physically-crosslinked networks, the organic-inorganic PCL stars displayed significant shape memory properties with about 100% of shape recovery, which was in marked contrast to the PCL stars without UPy termini.

关键词： POSS PCL Physical crosslinking Shape memory properties

Delivery methods for CRISPR/Cas9 gene editing in crustaceans

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Marine Life Science & Technology 2020年第1期2卷 1-5页

作者： sen xu Thinh Phu Pham Swatantra Neupane Department of Biology University of Texas at Arlington501 S.Nedderman Dr.ArlingtonTX 76019USA

In this mini-review,we provide an up-to-date overview of the delivery methods that have been used for CRISPR/Cas9 genomic editing in crustacean *** embryonic microinjection as the main workforce for delivering CRISPR/Cas9 reagents,biologists working with crustacean species have to tackle the technical challenges involved in *** use examples of three Crustacean species(the branchiopod Daphnia,amphipod Parhyale hawaiensis,and decapod Exopalaemon carinicauda)to provide a technical guide for embryonic ***,we outline two potentially useful new techniques for delivering CRISPR/Cas9 components into crustaceans,i.e.,Receptor-Mediated Ovary Transduction of Cargo(ReMOT Control)and electroporation.

关键词： Microinjection Electroporation Vitellogenesis Daphnia Parhyale hawaiensis Exopalaemon carinicauda

A nonprofiled side-channel analysis based on variational lower bound related to mutual information

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Science China(Information Sciences) 2023年第1期66卷 277-295页

作者： Chi ZHANG Xiangjun LU Pei CAO Dawu GU Zheng GUO sen xu School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Zhi xun Crypto Testing and Evaluation Technology Co. Ltd. 3. Viewsource Information Science and Technology Co. Ltd.

In this paper, we attempt to improve the practical performance of the nonprofiled side-channel analysis(Non SCA) with the help of neural networks. We first derive a variational lower bound related to mutual information(VLBRMI) optimized for the context of Non SCA, which possesses a set of adjustable parameters and whose maximum value linearly depends on the mutual information. Then, we propose a new Non SCA method called neural mutual information analysis(NMIA) that exploits the maximum VLBRMI as the distinguisher. We present an estimator of the maximum VLBRMI, which uses neural networks to instantiate the VLBRMI and trains the neural networks to approximate the maximum VLBRMI so that we can implement the NMIA efficiently. Finally, we evaluate the NMIA on several datasets. The experimental results show that NMIA outperforms the correlation power analysis, the mutual information analysis(MIA)based on histograms, the MIA based on kernel density estimation, and the state-of-the-art Non SCA method based on neural networks.

关键词： side-channel analysis nonprofiled method variational lower bound mutual information neural networks

Wide Pulse Width Electroacupuncture Ameliorates Denervation-Induced Skeletal Muscle Atrophy in Rats via IGF-1/PI3K/Akt Pathway

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Chinese Journal of Integrative Medicine 2021年第6期27卷 446-454页

作者： HUANG Xiao-qing xu Jin-sen YE Xiao-ran CHEN xuan Key Laboratory of Acupuncture Instrument Fujian Academy of Chinese Medical SciencesFuzhou(350003)China Fujian Key Laboratory of Propagated sensation along Meridian Institute of Meridians and Collaterals MedicineFujian Academy of Chinese Medical SciencesFuzhou(350003)China

Objective:To evaluate the effect of the pulse width of electroacupuncture(EA)in the treatment of denervation-induced skeletal muscle atrophy in rats and examine the role of insulin-like growth factor 1(IGF-1)/phosphatidylinositol 3-kinase(PI3 K)/Akt signaling pathway during ***:Sciatic nerve functional index(SFI),muscle wet weight and the cross-sectional area(CSA)of the gastrocnemius muscle were analyzed after treatment in model rats with EA of various pulse widths(0.5,50,100 and 200 ms).The apoptosis index(AI)and paired box(PAX)3 and PAX7 protein expression were also ***,the mRNA and protein expressions of components of IGF-1/PI3 K/Akt pathway and their downstream targets were determined,along with the inhibiting effect of the pathway with a PI3-specific ***:EA with a pulse width of 200 ms was found to have the best effect with regard to increasing SFI,CSA and muscle weight,decreasing AI,and increasing the expression of PAX3 and *** IGF-1/PI3 K/Akt pathway was found to be activated by denervation,although the downstream forkhead box O(FoxO)pathway was not suppressed by its *** PI3 K/Akt pathway and its downstream molecule mammalian target of rapamycin(mTOR)were up-regulated further by EA to promote muscle protein ***,the expressions of downstream FoxO and F-box protein 32(ATROGIN-1)were down-regulated to reduce protein ***:EA with 200-ms pulse width was found to have a more significant effect than 0.5-ms *** positive effects of EA disappeared after inhibition of the PI3 K/Akt pathway.

关键词： denervation muscle atrophy electroacupuncture pulse width IGF-1/PI3K/Akt pathway

In-situ carbonizing of coal pitch on the surface of silica sphere as quasi-graphitized carbon stationary phase for liquid chromatography

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Chinese Chemical Letters 2023年第7期34卷 219-221页

作者： sen xu Zhihua Zhong Yu Wang Lingyi Zhang Weibing Zhang Shanghai Key Laboratory of Functional Materials Chemistry School of Chemistry&Molecular EngineeringEast China University of Science and Technology.Shanghai200237China

A novel chromatography stationary phase with a quasi-graphitized carbon modified shell has been developed. Coal pitch was directly carbonized on the surface of porous silica with in-situ carbonization. The carbonized coal pitch coating exhibits some degree of graphitization with a 78 nm-thick layer on the surface of silica and a 0.5 nm-thick layer on the inner surface of the mesopores. Based on the special structure of the graphitized carbon coating, the novel stationary phase can provide multiple interactions such as hydrophobic interaction, π-π interaction and dipole-dipole interaction. The novel composite material exhibited unique separation selectivity and excellent separation efficiency for polar compounds, including imidazoles, nucleosides and pesticides. Besides, the packed column also exhibited great repeatability with the RSDs of the retention time of nucleosides between 0.07%-0.50%(n = 5). Finally, satisfied result was achieved in the separation of fullerenes on the new column, suggesting the great potential in the industrial-scale purification of fullerenes.

关键词： Graphitized carbon Coal pitch High performance liquid chromatography Chromatographic separation Fullerenes

Automatically Identifying Calling-Prone Higher-Order Functions of Scala Programs to Assist Testers

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Journal of Computer Science & Technology 2020年第6期35卷 1278-1294页

作者： Yi-sen xu Xiang-Yang Jia Fan Wu Lingbo Li Ji-Feng xuan School of Computer Science Wuhan UniversityWuhan 430072China Turing Intelligence Technology Limited LondonEC2Y 9STU.K.

For the rapid development of internetware, functional programming languages, such as Haskell and Scala, can be used to implement complex domain-specific applications. In functional programming languages, a higher-order function is a function that takes functions as parameters or returns a function. Using higher-order functions in programs can increase the generality and reduce the redundancy of source code. To test a higher-order function, a tester needs to check the requirements and write another function as the test input. However, due to the complex structure of higher-order functions, testing higher-order functions is a time-consuming and labor-intensive task. Testers have to spend an amount of manual effort in testing all higher-order functions. Such testing is infeasible if the time budget is limited, such as a period before a project release. In practice, not every higher-order function is actually called. We refer to higher-order functions that are about to be called as calling-prone ones. Calling-prone higher-order functions should be tested first. In this paper, we propose an automatic approach, namely PHOF, which predicts whether a higher-order function of Scala programs will be called in the future, i.e., identifying calling-prone higher-order functions. Our approach can assist testers to reduce the number of higher-order functions of Scala programs under test. In PHOF, we extracted 24 features from source code and logs to train a predictive model based on known higher-order function calls. We empirically evaluated our approach on 4832 higher-order functions from 27 real-world Scala projects. Experimental results show that PHOF based on the random forest algorithm and the Synthetic Minority Oversampling Technique Processing strategy (SMOTE) performs well in the prediction of calls of higher-order functions. Our work can be used to support the scheduling of limited test resources.

关键词： higher-order function testing tool test management Scala program internetware