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The saproxylic beetle assemblage associated with different host trees in Southwest China

Insect Science 2008年第3期15卷 251-261页

作者： Jie Wu xiao-dong yu Hong-Zhang Zhou Institute of Zoology Chinese Academy of Sciences Beijing China

Dead wood is a habitat for many insects and other small animals, some of which may be rare or endangered and in need of effective protection. In this paper, saproxylic beetle assemblages associated with different host trees in the subtropical forests in southwestern China were investigated. A total of 277 species （1 439 specimens） in 36 beetle families were collected from 117 dead wood samples, of which 101 samples were identified and respectively belonged to 12 tree genera. The number of saproxylic beetle species varied greatly among logs of different tree genera, with the highest diversity on logs of Juglans. Generally, broad-leaved trees had a higher richness and abundance of saproxylic species than coniferous trees. Cluster analysis revealed that assemblages from broad-leaved tree genera were generally similar （except for Betula） and assemblages from coniferous trees formed another distinct cluster. The subsequent indicator analysis proposed that there are different characteristic species for different cluster groups of host tree genera. In our study, log diameter has no positive influence on beetle species density. Conversely, comparisons of individual-based rarefaction curves suggested that beetle species richness was highest in the small diameter class both in coniferous and broad-leaved tree genera. With increased wood decay, proportion of habitat specialists （saproxylic beetles living on one tree genus） decreased, whereas proportion of habitat generalists （living on more than three tree genera） increased. The beetle species density was found to be higher in early stages, and decreased in later stages as well. A negative influence of altitude on saproxylic beetle species richness and abundance was detected. It was indicated that different tree genera and altitudes possibly display cross effects in modulating the altitudinal distribution and host preference of the beetles.

关键词： China host trees Saproxylic beetle subtropical forest

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Treatment status of extremely premature infants with gestational age<28 weeks in a Chinese perinatal center from 2010 to 2019

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World Journal of Pediatrics 2022年第1期18卷 67-74页

作者： Wen-Wen Zhang Yong-Hui yu xiao-yu dong Simmy Reddy Department of Neonatology Shandong Provincial Hospital Afliated to Shandong First Medical UniversityJinan 250021China Department of Neonatology Shandong Maternal and Child Health HospitalJinan 250021China Cheeloo College of Medicine Shandong UniversityJinanChina

Background There is a paucity of studies conducted in China on the outcomes of all live-birth extremely premature infants(EPIs)and there is no unifed recommendation on the active treatment of the minimum gestational age in the feld of perinatal medicine in *** aimed to investigate the current treatment situation of EPIs and to provide evidence for formulating reasonable treatment *** We established a real-world ambispective cohort study of all live births in delivery rooms with gestational age(GA)between 24+0 and 27+6 weeks from 2010 to *** Of the 1163 EPIs included in our study,241(20.7%)survived,while 849(73.0%)died in the delivery room and 73(6.3%)died in the neonatal intensive care *** all included EPIs,862(74.1%)died from withholding or withdrawal of *** of stratifcation according to GA or birth weight,the proportion of total mortality attributable to withdrawal of care is *** infants with the GA of 24 weeks,active treatment did not extend their survival time(P=0.224).The survival time without severe morbidity of the active treatment was signifcantly longer than that of withdrawing care for infants older than 25 weeks(P<0.001).Over time,the survival rate improved,and the withdrawal of care caused by socioeconomic factors and primary nonintervention were reduced signifcantly(P<0.001).Conclusions The mortality rate of EPIs is still *** of care is common for EPIs with smaller GA,especially in the delivery *** is necessary to use a multi-center,large sample of real-world data to fnd the survival limit of active treatment based on our treatment capabilities.

关键词： Active treatment Extremely premature Infants Mortality rate Withdrawal of care

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Composition and distribution of ground-dwelling beetles among oak fragments and surrounding pine plantations in a temperate forest of North China

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Insect Science 2014年第1期21卷 114-124页

作者： xiao-dong yu Tian-Hong Luo Hong-Zhang Zhou Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing China

In this study, we compared ground-dwelling beetle assemblages （Coleoptera） from a range of different oak fragments and surrounding conifer plantations to evaluate effects of forest size and surrounding matrix habitat in a temperate forest of north China. During 2000, beetles were sampled via pitfall traps within two large oak fragments （ca. 2.0-4.0 ha）, two small oak fragments （ca. 0.2-0.4 ha） and two surrounding matrices dom- inated by pine plantations （〉4 ha） in two sites of different aspects. Overall, no significantly negative effects from forest patch size and the surrounding matrix habitat were detected in total species number and abundance of ground-dwelling beetles. However, compared with small oak patches or pine plantations, more species were associated with an affinity for at least one large oak patch of the two aspects. Multivariate regression trees showed that the habitat type better determined the beetle assemblage structure than patch size and aspect, indicating a strong impact of the surrounding matrix. Linear mixed models indicated that species richness and abundance of all ground-dwelling beetles or beetle families showed different responses to the selected environmental variables. Our results suggest that more disturbed sites are significantly poorer in oak forest specialists, which are usually more abundant in large oak fragments and decrease in abundance or disappear in small fragments and surrounding matrix habitats. Thus, it is necessary to preserve a minimum size of forest patch to create conditions characteristic for forest interior, rather than the more difficult task of increasing habitat connectivity.

关键词： forest patch size fragmentation ground-dwelling beetles North China,surrounding matrix habitat temperate forest

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Statistical Optimization of Medium Components for Improved Product Ion of Recombinant Hyperthermophilic Esterase

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Chemical Research in Chinese Universities 2006年第2期22卷 134-138页

作者： REN xiao-dong yu Da-wei HAN Si-ping FENG Yan Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education Jilin University Changchun 130021 P. R. China

The optimization of nutrient levels for the production of recombinant hyperthermophilie esterase by E. coli was carried out with response surface methodology（RSM） based on the central composite rotatable design（CCRD）. A 24 central composite rotatable design was used to study the combined effect of the nutritional constituents like yeast extract, peptone, mineral salt and trace metals. The P-value of the coefficient for the linear effect of peptone concentration was 0. 0081 and trace metals solution was less than 0. 0001, suggesting that these were the principal variables with significant effect on the hyperthermophilic esterase production. The predicted optimal hyperthermophilie esterase yield was 269. 17 U/mL, whereas an actual experimental value of 284. 58 U/mL was obtained.

关键词： Optimization Medium components Recombinant hyperthermophilic esterase and response surface methodology

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Topological dynamical decoupling

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Science China(Physics,Mechanics & Astronomy) 2019年第12期62卷 2-9页

作者： Jiang Zhang xiao-dong yu Gui-Lu Long Qi-Kun Xue State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China Naturwissenschaftlich-Technische Fakultcit Universitat SiegenWaiter-Flex-Strafie 357068 SiegenGermany Beijing National Research Center for Information Science and Technology Beijing 100084China Collaborative Innovation Center of Quantum Matter Beijing 100084China

We show that topological equivalence classes of circles in a two-dimensional square lattice can be used to design dynamical decoupling procedures to protect qubits attached on the edges of the lattice. Based on the circles of the topologically trivial class in the original and the dual lattices, we devise a procedure which removes all kinds of local Hamiltonians from the dynamics of the qubits while keeping information stored in the homological degrees of freedom unchanged. If only the linearly independent interaction and nearest-neighbor two-qubit interactions are concerned, a much simpler procedure which involves the four equivalence classes of circles can be designed. This procedure is compatible with Eulerian and concatenated dynamical decouplings,which make it possible to implement the procedure with bounded-strength controls and for a long time period. As an application,it is shown that our method can be directly generalized to finite square lattices to suppress uncorrectable errors in surface codes.

关键词： dynamical decoupling surface codes topological quantum computation

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Effects of insect-resistant transgenic cotton on ground-dwelling beetle assemblages(Coleoptera)

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Journal of Integrative Agriculture 2016年第2期15卷 381-390页

作者： ZHAO Cai-yun yu xiao-dong LIU Yong-bo LI Jun-sheng State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of Sciences

We compared the ground-dwelling beetle assemblages under four scenarios in which transgenic Bt（Cry 1Ac） cotton（33B）,transgenic Bt（Cry 1Ac）＋CpTI cotton（SGK321）,conventional cotton（33）,conventional cotton（Shiyuan 321） in North *** the survey in two years（2009-2010）,24 ground beetle species were captured with pitfall traps in 20 plots which included five replicates for each cotton *** significant difference was observed in the number of ground beetle species captured,activity density,evenness and Shannon-Wiener diversity among the four cotton *** posticalis was less abundant in transgenic Bt＋CpTI cotton（SGK321） fields than its conventional cotton（Shiyuan 321）,but more abundant in transgenic Bt cotton（33B） fields compared with its conventional cotton（33）.There was no significant difference for other abundant species between in transgenic cotton and in conventional cotton *** on non-metric multidimensional scaling（NMDS） analysis,ground-dwelling beetle assemblages were similar in transgenic and conventional cotton over the two years,but the ground-dwelling beetle assemblages in transgenic cotton 33 B significantly differed from that in the conventional cotton（strain 33） in *** strong evidence that the transgenic cotton effect on ground-dwelling beetle assemblages was found in this study.

关键词： biodiversity community cotton varieties non-target insects

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Acute exposure to high-peak-power pulsed microwaves affecting the histamine H_3 receptor expression in rat hippocampus

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Nuclear Science and Techniques 2006年第4期17卷 227-231页

作者： yu xiao-dong LI Bo LI De-Hua HE Qi-Yi yu Zheng-Ping Department of Occupational Health School of Preventive Medicine Third Military. Medical University Chongqing 400038China Chongqing Key Laboratory of Animal Sciences School of Biological Science Chongqing Normal University Chongqing 400037 China

In the Morris Water Maze test, high-peak-power pulsed microwave (MW)-exposed rats displayed some learning and memory behavior dysfunctions, and their escape time and swimming distance to the submerged platform were longer than those of the sham-exposed rats. To understand the molecular mechanism involved, the reverse tran- scription-polymerase chain reaction (RT-PCR) and the Western-blotting technique were used for investigating the mRNA and protein expression patterns of the histamine H3 receptor (H3R) in rat hippocampus. High-peak-power pulsed microwave-exposure did not remarkably lead to the change in expression of H3R mRNA in rat hippocampi; however, it promoted the up-regulatory expression of the H3R protein, which was possibly triggered through the mi- togen-activated protein kinase (MAPK) pathways. Therefore, further investigation of the molecular mechanism of the MW effects on the learning and memory behaviors is required.

关键词：组胺H3受体大鼠海马微波辐照表达

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Water hammer protection for diversion systems in front of pumps in long-distance water supply projects

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Water Science and Engineering 2023年第2期16卷 211-218页

作者： Lin Shi Jian Zhang xiao-dong yu Sheng Chen Wen-long Zhao Xu-yun Chen College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China

For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention. In this study, a water hammer protection scheme combined with an overflow surge tank and a regulating valve was developed. A mathematical model of the overflow surge tank was developed, and an analytical formula for the height of the overflow surge tank was derived. Furthermore, a practical water supply project was used to evaluate the feasibility of the combined protection scheme and analyze the sensitivity of valve regulation rules. The results showed that the combined protection scheme effectively reduced the height of the surge tank, lessened the difficulties related to construction, and reduced the necessary financial investment for the project. The two-stage closing rule articulated as fast first and then slow could minimize the overflow volume of the surge tank when the power failure occurred, while the two-stage opening rule articulated as slow first and then fast could be more conducive to the safety of the water supply system when the pump started up.

关键词： Long-distance diversion pipeline Water supply Water hammer Overflow surge tank Regulating valve

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Constructing energetic covalent organic frameworks with high stability and low sensitivity

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Chinese Chemical Letters 2024年第3期35卷 544-548页

作者： Hui-Min Guo xiao-yu dong Shan Wang Qian-You Wang Shuang-Quan Zang Henan Key Laboratory of Crystalline Molecular Functional Materials Green Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China

Developing new functional explosives that display high stability,good energy performance,and low sensitivity are one of the key directions of energetic materials *** this work,two-dimensional(2D)Schiff-based energetic covalent organic frameworks(COFs)are prepared based on triaminoguanidine salts with different anions as building *** from the robust covalent bond in 2D extended polygons and strongπ-πinteractions in the eclipsed interlayers,the synthesized energetic COFs showed higher thermal stability and lower mechanical sensitivity than their precursor *** importantly,incorporating triaminoguanidine salts into COFs effectively increase the corrosion resistance to metal under high humidity conditions,which is due to the imine moieties in COFs functioning asπacceptors and offering strong bonding with metallic *** work provides a new pathway for the development of high-performance energetic materials.

关键词： Covalent organic frameworks Energetic materials High thermal stability Low sensitivity Corrosion resistance

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THE EFFECT OF OIL CAVITY DEPTH ON TEMPERATURE FIELD IN HEAVY HYDROSTATIC THRUST BEARING

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Journal of Hydrodynamics 2011年第5期23卷 676-680页

作者： SHAO Jun-peng DAI Chun-xi ZHANG Yan-qin yu xiao-dong XU xiao-qiu WANG yun-fei College of Mechanical and Power Engineering Harbin UniverSity of Science and Technology Harbin150080 China

For a heavy hydrostatic bearing with a high linear velocity, the results of numerical calculations often differ from practical conditions if the viscosity is considered as constant. In this article, the influence of the oil cavity depth on the temperature field in the heavy hydrostatic bearing is discussed in the context of variable viscosity. The viscosity-temperature relations for the gap oil film are first established by fitting B-Spline curves, then, numerical calculations for the temperature field in the heavy hydrostatic bearing of different oil cavity depths are carried out based on Finite Volume Method （FVM） under the same rotating speed, and the influence of the oil cavity depth on the temperature distribution in the gap oil film of the hydrostatic bearing is discussed. The results of numerical calculations provide the temperature distribution state inside the hydrostatic bearing, which would help the selection and the design of hydrostatic bearings in engineering practice.

关键词： hydrostatic thrust bearing viscosity-temperature characteristic Finite Volume Method (FVM) temperature field

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