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Top-down control on major groups of global marine diazotrophs

Acta Oceanologica Sinica 2022年第8期41卷 111-119页

作者： hua Wang ya-Wei Luo State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China College of Ocean and Earth Sciences Xiamen UniversityXiamen 361102China

Dinitrogen(N_(2))fixed by a group of prokaryotes(diazotrophs)is the dominant process adding bioavailable nitrogen into the *** it has been intensively studied how N_(2) fixation is controlled by resources(bottom-up factors),it is unclear whether the grazing(top-down control)effectively impacts growth and distribution of different diazotroph *** this study,we evaluate this question by conducting log-log regression of diazotroph biomass onto corresponding N_(2) fixation rates in the global *** slope of the regression for Trichodesmium is~0.8,indicating that a small portion of the increase in N_(2) fixation does not accumulate as its *** leads to a conclusion that Trichodesmium is under a substantial top-down control,although bottom-up control still *** also analyze the residuals of the regression in the North Atlantic,concluding that free trichomes of Trichodesmium are subject to stronger top-down control than its *** weak correlation between the biomass and N_(2) fixation of unicellular cyanobacterial diazotrophs indicates that the degree of top-down control on this type of diazotrophs varies *** analyses obtain unrealistic results for diatom-diazotroph assemblages due to complicated nitrogen sources of these *** study reveals the variability of top-down control among different diazotroph groups across time and space,suggesting its importance in improving our understandings of ecology of diazotrophs and predictions of N_(2) fixation in biogeochemical *** of size-specific N_(2) fixation rates and growth rates of different diazotroph groups can be useful to more reliably analyze the top-down control on these key organisms in the global ocean.

关键词： marine diazotrophs nitrogen fixation top-down control bottom-up control Trichodesmium diatom-diazotroph assemblages

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What are the keys to influence the life satisfaction of eco-migrants in the northern foot of the Qilian Mountains?A test based on the livelihood risk interaction

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Journal of Mountain Science 2022年第11期19卷 3227-3245页

作者： WANG ya ZHOU Li-hua Key Laboratory of Desert and Desertification Northwest Institute of Eco-environment and ResourcesChinese Academy of SciencesLanzhou 730000China Institutes of Science and Development Chinese Academy of SciencesBeijing 100190China School of public policy and management University of Chinese Academy of SciencesBeijing 100049China

Eco-migrants'ability to adapt to livelihood risks and their satisfaction with lives directly affect the ecological and economic benefits of ecological migration *** formulate an effective livelihood risk prevention system and welfare guarantee mechanism,we took the ecomigrants in Wuwei City as an example,developed an integrated analytical framework for life satisfaction and employed linear regression models to identify the interactions between livelihood risk and life *** findings indicate that 94.66%of eco-migrants in Wuwei City are threatened by livelihood risks after *** living expenses,poor quality of redistributed production goods,and re-poverty constitute the main *** risk multiplicity index is *** cultural types,there are no significant differences in regions and livelihoods.A total of 55.73%of eco-migrants are satisfied with their lives,with the Liangzhou district scoring the *** for satisfaction with development potential and public services,no significant intergroup differences were found among regions and livelihood ***-migrant's life satisfaction is significantly affected by livelihood ***-migrants'satisfaction with living income,social integration,farmer-friendly policies and overall life is negatively affected by the risk of repoverty and inadequate social *** ecomigrant's satisfaction with development potential and community construction is not influenced by one type of risk alone,but the interaction between risks has a strong *** interaction of welfare risks with economic risks and policy risks will balance and weaken the adverse effects of a single risk on those elements in the economic and policy *** study offers novel ideas for rural revitalization,hollow governance,and well-being assurance.

关键词： Eco-migrant Livelihood risk Life satisfaction Northern foot of Qilian Mountain

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A mathematical model of cortical bone remodeling at cellular level under mechanical stimulus

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Acta Mechanica Sinica 2012年第6期28卷 1678-1692页

作者： Qing-hua Qin ya-Nan Wang Research School of Engineering The Australian National University

A bone cell population dynamics model for cor- tical bone remodeling under mechanical stimulus is devel- oped in this paper. The external experiments extracted from the literature which have not been used in the creation of the model are used to test the validity of the model. Not only can the model compare reasonably well with these ex- perimental results such as the increase percentage of final values of bone mineral content （BMC） and bone fracture en- ergy （BFE） among different loading schemes （which proves the validity of the model）, but also predict the realtime devel- opment pattern of BMC and BFE, as well as the dynamics of osteoblasts （OBA）, osteoclasts （OCA）, nitric oxide （NO） and prostaglandin E2 （PGE2） for each loading scheme, which can hardly be monitored through experiment. In conclusion, the model is the first of its kind that is able to provide an in- sight into the quantitative mechanism of bone remodeling at cellular level by which bone cells are activated by mechan- ical stimulus in order to start resorption/formation of bone mass. More importantly, this model has laid a solid foun- dation based on which future work such as systemic control theory analysis of bone remodeling under mechanical stimu- lus can be investigated. The to-be identified control mecha- nism will help to develop effective drugs and combined non- pharmacological therapies to combat bone loss pathologies. Also this deeper understanding of how mechanical forces quantitatively interact with skeletal tissue is essential for the generation of bone tissue for tissue replacement purposes in tissue engineering.

关键词： Cortical bone remodeling Cell population dy-namics Mechanotransduction Mechanosensitivity Bonefracture energy - Bone mineral content

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Stability and Chaos of Two Coupled Bose-Einstein Condensates with Three-Body Interaction

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Communications in Theoretical Physics 2005年第5X期44卷 840-846页

作者： LI ya HAI Wen-hua Department of Physics Hunan Normal University Changsha 410081 China

We study the dynamics of two Bose-Einstein condensates (BECs) tunnel-coupled by a double-well potential.A real three-body interaction term is considered and a two-mode approximation is used to derive two coupled equations,which describe the relative population and relative phase. By solving the equations and analyzing the stability of the system, we find the stable stationary solutions for a constant atomic scattering length. When a periodically time-varying scattering length is applied, Melnikov analysis and numerical calculation demonstrate the existence of chaotic behavior and the dependence of chaos on the three-body interaction parameters.

关键词： Bose-Einstein condensate stability chaos Melnikov function

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A molecular dynamics investigation of the deformation mechanism and shape memory effect of epoxy shape memory polymers

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Science China(Physics,Mechanics & Astronomy) 2016年第3期59卷 89-95页

作者： hua yang Zheng Dao Wang ya Fang Guo Xing hua Shi Institute of Engineering Mechanics Beijing Jiaotong University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences

Following deformation, thermally induced shape memory polymers(SMPs) have the ability to recover their original shape with a change in temperature. In this work, the thermomechanical properties and shape memory behaviors of three types of epoxy SMPs with varying curing agent contents were investigated using a molecular dynamics(MD) method. The mechanical properties under uniaxial tension at different temperatures were obtained, and the simulation results compared reasonably with experimental data. In addition, in a thermomechanical cycle, ideal shape memory effects for the three types of SMPs were revealed through the shape frozen and shape recovery responses at low and high temperatures, respectively, indicating that the recovery time is strongly influenced by the ratio of E-51 to 4,4'-Methylenedianiline.

关键词： shape memory polymer molecular dynamics simulation thermomechanics

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New Tripartite Nonlinear Entangled State Representation in Quantum Mechanics

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Communications in Theoretical Physics 2008年第10期50卷 867-872页

作者： KUANG mai-hua MA Shan-Jun LIU Dong-Mei College of Physics ＆ Communication Electronics Jiangxi Normal University Nanchang 330022 China

Based on the technique of integral within an ordered product of nonlinear bosonic operators,we constructa new kind of tripartite nonlinear entangled state |α,γ〉_λ in 3-mode Fock space,which can make up a complete ... 详细信息

关键词： nonlinear 3-mode entangled state

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High-resolution Absorption Spectra of Acetylene in 142.8-152.3 nm

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Chinese Journal of Chemical Physics 2008年第5期21卷 415-420页

作者： ya-hua Hu Chen Zhen Jing-hua Dai Xiao-guo Zhou Shi-lin Liu Hefei National Laboratory for Physical Sciences at Microscale Department of Chemical Physics University of Science and Technology of China Hefei 230026 China

The absorption spectra of acetylene molecules was measured under jet-cooled conditions in the wavelength range of 142.8-152.3 nm, with a tunable and highly resolved vacuum ultraviolet （VUV） laser generated by two-photon resonant four wave difference frequency mixing processes. Due to the sufficient vibrational and rotational cooling effect of the molecular beam and the higher resolution VUV laser, the observed absorption spectra exhibit more distinct spectral features than the previous works measured at room temperature. The major three vibrational bands are assigned as a C-C symmetry stretching vibrational progress （v2=0.2） of the C^1Πu state of acetylene. The observed shoulder peak at 148,2 nm is assigned to the first overtone band of the trans-bending mode V4 of the C^1Πu state of acetylene. Additionally, the two components, 4^20（μ^1Π） and 4^20（k^1Πu）, are suggested to exhibit in the present absorption spectra, due to their Renner-Teller effect and transition selection rule. All band origins and bandwidths are obtained subsequently, and it is found that bandwidths are broadened and lifetimes decrease gradually with the excitation of vibration.

关键词： Acetylene Vacuum ultraviolet Absorption spectrum

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Increased Midkine and Estrogen Receptor-β Expression in Human Non-Small Cell Lung Cancer

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Chinese Journal of Cancer Research 2009年第4期21卷 255-264页

作者： Shi-hua Zhang Guang-feng Zhao ya-hong huang Kai-hua Lu ya-yi HOU Immunology and Reproduction Biology Lab Medical School ＆ State Key Laboratory of Pharmaceutical Biotechnology Nanjing University Nanjing 210093 China The People＇s Hospital of Jiangsu Province Nanjing 210029 China Key Laboratory of Molecular Medicine of Jiangsu Province Nanjing 210093 China

Objective： Midkine （MK）, a new member of the heparin-binding growth factor family, has been found recently to have a high expression level in many tumor specimens including lung carcinoma. Estrogens may be involved in lung carcinogenesis, and estrogen receptors, mainly estrogen receptor-β （ER-β）, are present and functional in normal lung and tumor cell lines and tissues. In addition, estrogens and growth factors may promote the progression of human non-small cell lung cancer （NSCLC）. Previously, we have immunohistochemically demonstrated that MK and ER-β proteins were overexpressed in NSCLC and their expression levels were both significantly negatively correlated with the pathological classification. The purpose of this study was to further verify their expression and its correlation with NSCLC. Methods： Taking NSCLC tissues and their corresponding paraneoplastic and normal lung as research objects, we further examined the expression of MK and ER-β by meas of RT-PCR, in situ hybridization and Western blot analyses at the levels of messenger RNA （mRNA） and protein, respectively. Results： The increased MK and ER-β mRNA expression was found in NSCLC by RT-PCR and in situ hybridization analyses. Furthermore, Western blot analysis also displayed increased expression of MK and ER-β proteins in NSCLC. Finally, their correlation analysis at the levels of mRNA and protein expression in NSCLC demonstrated that MK protein level was significantly correlated to estrogen receptor-β （P〈0.01, rs=0.535）; in spite of their correlation at the mRNA level, there was no remarkable difference between MK and ER-β （P〉0.05, rs=0.178）. Conclusion： All these results in the present study confirmed that MK and ER-β were overexpressed in human NSCLC.

关键词： Midkine (MK) Estrogen receptor-β (ER-β) Non-small cell lung cancer (NSCLC)

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Analgesic effect of ultrasound-guided bilateral transversus abdominis plane block in laparoscopic gastric cancer

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World Journal of Gastrointestinal Surgery 2023年第10期15卷 2171-2178页

作者： ya-ya Wang hua-Jun Fu Department of Anesthesiology Shaanxi Provincial People’s HospitalXi'an 710068Shaanxi ProvinceChina

BACKGROUND Postoperative complications are important factors affecting the survival time and quality of life of patients undergoing radical *** To investigate and compare the anesthetic effects of intravenous general anesthesia combined with epidural anesthesia or ultrasound-guided bilateral transversus abdominal plane block(TAPB)in gastric cancer patients undergoing laparoscopic radical *** The clinical data of 85 patients who underwent laparoscopic radical gastrectomy in our hospital from December 2020 to January 2023 were retrospectively collected and divided into a TAPB group(n=45)and epidural anesthesia group(n=40)according to the different anesthesia and analgesia programs *** TAPB group received general anesthesia combined with TAPB,and the epidural anesthesia group received general anesthesia combined with epidural *** pain status,cognitive status,intestinal barrier indicators,recovery quality,and incidence of complications were compared between the two *** Compared with the epidural anesthesia group,the TAPB group’s visual analog scale scores were significantly lower 6 h,12 h,24 h and 48 h after surgery(P<0.05).The incidence of postoperative cognitive dysfunction(POCD)in the TAPB group was significantly lower than that in the epidural anesthesia group,and the Mini-mental State Examination score 24 h after surgery was significantly higher in the TAPB group than the epidural anesthesia group(P<0.05).The levels of diamine oxidase and plasma D-lactate were significantly lower in the TAPB group than the epidural anesthesia group 24 h after surgery(P<0.05).The agitation score and the incidence of agitation during recovery were significantly lower in the TAPB group than epidural anesthesia group(P<0.05).The total incidence of postoperative complications in the TAPB group was 4.44%,significantly lower than the 20.00%in the epidural anesthesia group(P<0.05).CONCLUSION Compared with epidural anesthesia combined w

关键词： Laparoscopic radical gastrectomy Ultrasound-guided bilateral transversus abdominal plane block Cognitive impairment Intestinal barrier function

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SYNTHESIS OF STYRYL-CAPPED POLYPROPYLENE via METALLOCENE-MEDIATED COORDINATION POLYMERIZATION: APPLY TO POLYPROPYLENE MACROMOLECULAR ENGINEERING

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Chinese Journal of Polymer Science 2013年第4期31卷 550-562页

作者： hua-hua huang Chuan-hui Zhang ya-wei Qin Hui Niu 董金勇 CAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

In this paper, we review our recent progress in the synthesis and application of styryl-capped polypropylene （PP-t- St）, an excellent reactive polyolefin that is both convenient and efficient in synthesis and facile and versatile in application for preparing advanced polypropylene materials via macromolecular engineering. The synthesis of PP-t-St is made possible by a unique chain transfer reaction coordinated by a bis-styrenic molecule, such as 1,4-divinylbenzene （DVB） and 1,2-bis（4- vinylphenyl）ethane （BVPE）, and hydrogen in typical C2-symmetric metallocene （e.g. rac-Me2Si（2-Me-4-Ph-Ind）2ZrC12, in association with methylaluminocene, MAO） catalyzed propylene polymerization. The regio-selective 2,1- insertion of the styrenic double bond in DVB or BVPE into the overwhelmingly 1,2-fashioned Zr-PP propagating chain enables substantial dormancy of the catalyst active site, which triggers selective hydrogen chain transfer that, with the formed Zr-H species ultimately saturated by the insertion of propylene monomer, results in an exclusive capping of the afforded PP chains by styryl group at the termination end. With a highly reactive styryl group at chain end, PP-t-St has been used as a facile building block in PP macromolecular engineering together with the employment of state-of-the-art synthetic polymer chemistry to fabricate broad types of new polypropylene architectures.

关键词： Polypropylene Coordination polymerization Styryl terminal group Macromolecular engineering.

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