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稀有金属材料与工程 2020年第3期49卷 769-777页

作者：李红梅兰丽刘达玉王卫薛慧玲漆文胜龚茂初陈耀强成都大学四川成都610106 四川大学绿色化学与技术教育部重点实验室四川成都610064

用共沉淀法制备了4种CeO2基储氧材料,并用X射线衍射(XRD),Raman光谱,N2吸附-脱附(BET方法),H2程序升温还原(H2-TPR),氧脉冲技术,X射线光电子能谱(XPS)和扫描电子显微镜(SEM)表征了其物理化学性质。XRD结果表明,在CeO2和CeO2-Al2O3(CA)... 详细信息

用共沉淀法制备了4种CeO2基储氧材料,并用X射线衍射(XRD),Raman光谱,N2吸附-脱附(BET方法),H2程序升温还原(H2-TPR),氧脉冲技术,X射线光电子能谱(XPS)和扫描电子显微镜(SEM)表征了其物理化学性质。XRD结果表明,在CeO2和CeO2-Al2O3(CA)中只能检测到宽的CeO2的特征峰,而CeO2-ZrO2(CZ)和CeO2-ZrO2-Al2O3(CZA)中检测到了Ce0.75Zr0.25O2相,所有的CeO2基储氧材料中都形成了均匀的固溶体。XPS结果表明,三价铈和四价铈共存于CZ,CA和CZA的表面,而在纯CeO2中几乎检测不到三价铈的存在。CZA表现出了最佳的织构性能,高的储氧量(OSC)和优异的热稳定性。另外,为了阐释4个样品的差异,提出了一种新的观点:Al3+可能插入了萤石结构的间隙或者高度分散在固溶体中。CZA固溶体可能是由间隙型固溶体和置换型固溶体混合组成的,这一点由CA和CZA中存在2种不同的氧化物或者2种类型的氧通道可以证明。然而,关于这个观点的详细证据还不够充分,需要继续进行深入的研究。

关键词： CeO2基储氧材料热稳定性共沉淀储氧量(OSC) Ce原子利用率

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Challenges for third sector organisations in cutback management: a sporting case study of the implications of publicness

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PUBLIC MANAGEMENT REVIEW 2020年第2期22卷 184-205页

作者： Bostock, James Breese, Richard Ridley-Duff, Rory Crowther, Philip Univ Derby Sport Outdoor & Exercise Sci Derby England Sheffield Hallam Univ Sheffield Business Sch Sheffield S Yorkshire England

Cutback management is a key theme for public services in an era of austerity, but the responsibilities for implementing public funding cutbacks do not always fall upon managers employed in the public sector. This article focuses on the cutbacks at third sector organisations (TSOs) - three national governing bodies (NGBs) of sport - which were affected by UK Sport's 'No Compromise' policy following the 2012 Olympics. The article introduces the public funding cutback decision hierarchy as a novel framework which is used alongside existing theory to assess the implications of the severity and immediacy of cutback.

关键词： Sport cutback publicness third sector

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Multifunctional Dual Ionic-Covalent Membranes for Wound Healing

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ACS BIOMATERIALS SCIENCE & ENGINEERING 2020年第12期6卷 6949-6960页

作者： Li, Zhi Chen, Sihao Wu, Baiqing Liu, Zulan Cheng, Lan Bao, Yu Ma, Yan Chen, Lei Tong, Xiaoling Dai, Fangyin Southwest Univ State Key Lab Silkworm Genome Biol Coll Text & Garment Chongqing 400715 Peoples R China Southwest Univ Chongqing Engn Res Ctr Biomat Fiber & Modern Text Coll Text & Garment Chongqing 400715 Peoples R China Southwest Univ State Key Lab Silkworm Genome Biol Minist Agr Coll Biotechnol Chongqing 400715 Peoples R China Southwest Univ Key Lab Sericultural Biol & Genet Breeding Minist Agr Coll Biotechnol Chongqing 400715 Peoples R China Southwest Univ State Key Lab Silkworm Genome Biol Chongqing Engn Res Ctr Biomat Fiber & Modern Text Coll Text & GarmentMinist AgrColl Biotechnol Chongqing 400715 Peoples R China Southwest Univ Chongqing Engn Res Ctr Biomat Fiber & Modern Text Coll Text & Garment Minist AgrColl Biotechnol Chongqing 400715 Peoples R China

Wound healing generally has four stages: hemostasis, inflammation, proliferation, and remolding. Most wound dressings only just take one or two phases into account. Herein, to develop a novel wound dressing that works at different stages, the blended alginate sodium/carboxymethyl chitosan membranes with a hydrogel-like structure are fabricated through a freeze-drying process together with a dual-ion (Sr2+ and Zn2+) cross-linking approach. The fabricated membranes show excellent properties in the swelling ratio, water vapor transmission rate, tensile strength, sustained release, cell adhesiveness, and biocompatibility, proving its general performance for application in wound healing. In particular, the membranes with optimal ion concentrations of 45 mM Sr2+ and 0.74 mM Zn2+ presented the antibacterial activity and accelerating function of wound healing. More specifically, the formation of epithelium and blood vessels is evidently advanced compared with a commercial dressing in vivo experiment, and the expression of main growth factors such as epidermal growth factor, basic fibroblast growth factor, vascular endothelial growth factor, and transforming growth factor is upregulated which also have good effects on the remolding of skin. The prepared wound dressings in this study have good effects on each stage of wound healing, which is important for the healing of chronic wounds. It provides more choices for wound healing, especially for chronic wound healing.

关键词： wound dressing hydrogel-like membranes growth factor angiogenesis chronic wound healing

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Nitrogen accumulation, rather than carbon: nitrogen stoichiometric variation, underlies carbon storage during forest succession

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ENVIRONMENTAL research LETTERS 2021年第2期16卷

作者： Zou, Junliang Wu, Juying Osborne, Bruce Tobin, Brian Luo, Yiqi Beijing Acad Agr & Forestry Sci Beijing Res & Dev Ctr Grass & Environm Beijing 100097 Peoples R China Univ Coll Dublin UCD Sch Biol & Environm Sci Dublin 4 Ireland Univ Coll Dublin UCD Earth Inst Dublin 4 Ireland Univ Coll Dublin Sch Agr & Food Sci UCD Forestry Dublin 4 Ireland No Arizona Univ Dept Biol Sci Ctr Ecosyst Sci & Soc Box 5640 Flagstaff AZ 86011 USA

Forest ecosystems play an important role in regulating global temperatures through their capability to take up and store CO2 from the atmosphere, but the magnitude and sustainability of this carbon (C) sink is critically dependent on the availability of nutrients, particularly nitrogen (N). However, the extent to which the absolute amount of N or modifications in plant and soil C:N ratios controls long-term forest carbon sequestration (C-seq) remains uncertain. To assess this, we analyzed the results of 135 global field studies that investigated the dynamics of C and N availability during forest succession. The results showed that the accumulation of C and N in plant (including above- and below-ground vegetation) and litter pools decreased with forest age and approached an equilibrium value in the latter stages of stand development. Plant and litter C:N ratios increased during the first 10-20 years and remained relatively stable thereafter. The analysis further showed that the relative importance of a change in the total amount of N or modifications in the C:N ratio, to increases in C-seq, varied with forest age. Whilst the relative importance of a change in the total amount of N increased with forest age, the relative importance of a varied C:N stoichiometry decreased with forest age. Overall, a change in the total amount of N was the more important factor contributing to C storage during forest stand development and the C stored in vegetation dominated the total ecosystem C pool. These results show that ecosystem N availability is a key factor supporting long-term forest C-seq during forest succession. As most of the C is found in above-ground vegetation, this pool is particularly susceptible to abiotic or biotic factors and anthropogenically-related disturbances.

关键词： carbon sink carbon– nitrogen coupling forest succession nitrogen limitation stand age stoichiometry

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DFT Investigation of the Structural, Electronic, and Optical Properties of AsTi (Bi)-Phase ZnO under Pressure for Optoelectronic Applications

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MATERIALS 2023年第21期16卷 6981-6981页

作者： Adnan, Muhammad Wang, Qingbo Sohu, Najamuddin Du, Shiyu He, Heming Peng, Zhenbo Liu, Zhen Zhang, Xiaohong Bai, Chengying Chinese Acad Sci Ningbo Inst Mat Technol & Engn Engn Lab Adv Energy Mat Ningbo 315201 Peoples R China Univ Chinese Acad Sci 19A Yuquan Rd Beijing 100049 Peoples R China GC Univ Hyderabad Sindh 71000 Pakistan China Univ Geosci Wuhan Sch Math & Phys Wuhan 430074 Peoples R China China Univ Petr East China Sch Mat Sci & Engn Qingdao 266580 Peoples R China Milky Way Sustainable Energy Ltd Zhuhai 519099 Peoples R China Univ Elect Sci & Technol China Yangtze Delta Reg Inst Huzhou 314299 Peoples R China Ningbo Polytech Inst Energy Storage & Convers Technol Ningbo 315800 Peoples R China Harbin Engn Univ Coll Mat Sci & Chem Engn Key Lab Superlight Mat & Surface Technol Minist Educ Harbin 150001 Peoples R China

Pressure-induced phases of ZnO have attracted considerable attention owing to their excellent electronic and optical properties. This study provides a vital insight into the electronic structure, optical characteristics, and structural properties of the AsTi (Bi) phase of ZnO under high pressure via the DFT-based first-principles approach. The phase transformation from BN(Bk) to the B-i phase of ZnO is estimated at 16.1 GPa using local density approximation, whereas the properties are explored precisely by the hybrid functional B3LYP. The electronic structure exploration confirms that the B-i phase is an insulator with a wider direct bandgap, which expands by increasing pressure. The dielectric function evidenced that the B-i phase behaves as a dielectric in the visible region and a metallic material at 18 eV. Optical features such as the refractive index and loss function revealed the transparent nature of the B-i phase in the UV range. Moreover, the considered B-i phase is found to possess a high absorption coefficient in the ultraviolet region. This research provides strong theoretical support for the development of Bi-phase ZnO-based optoelectronic and photovoltaic devices.

关键词： B-i-phase ZnO first-principles method B3LYP optoelectronic properties

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Search for topological defect dark matter with a global network of optical magnetometers

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NATURE PHYSICS 2021年第12期17卷 1396-+页

作者： Afach, Samer Buchler, Ben C. Budker, Dmitry Dailey, Conner Derevianko, Andrei Dumont, Vincent Figueroa, Nataniel L. Gerhardt, Ilja Grujic, Zoran D. Guo, Hong Hao, Chuanpeng Hamilton, Paul S. Hedges, Morgan Jackson Kimball, Derek F. Kim, Dongok Khamis, Sami Kornack, Thomas Lebedev, Victor Lu, Zheng-Tian Masia-Roig, Hector Monroy, Madeline Padniuk, Mikhail Palm, Christopher A. Park, Sun Yool Paul, Karun V. Penaflor, Alexander Peng, Xiang Pospelov, Maxim Preston, Rayshaun Pustelny, Szymon Scholtes, Theo Segura, Perrin C. Semertzidis, Yannis K. Sheng, Dong Shin, Yun Chang Smiga, Joseph A. Stalnaker, Jason E. Sulai, Ibrahim Tandon, Dhruv Wang, Tao Weis, Antoine Wickenbrock, Arne Wilson, Tatum Wu, Teng Wurm, David Xiao, Wei Yang, Yucheng Yu, Dongrui Zhang, Jianwei Helmholtz Inst Mainz GSI Helmholtzzentrum Schwerionenforsch Darmstadt Germany Australian Natl Univ Res Sch Phys Ctr Quantum Computat & Commun Technol Acton ACT Australia Australian Natl Univ Res Sch Phys Ctr Quantum Computat & Commun Technol Acton ACT Australia Univ Calif Berkeley Dept Phys Berkeley CA 94720 USA Univ Nevada Dept Phys Reno NV 89557 USA Lawrence Berkeley Natl Lab Computat Res Div Berkeley CA USA Inst Quantum Sci & Technol IQST Inst Phys 3 Stuttgart Germany Max Planck Inst Solid State Res Stuttgart Germany Univ Belgrade Inst Phys Belgrade Belgrade Serbia Univ Fribourg Phys Dept Fribourg Switzerland Peking Univ Dept Elect State Key Lab Adv Opt Commun Syst & Networks Beijing Peoples R China Peking Univ Ctr Quantum Informat Technol Beijing Peoples R China Univ Sci & Technol China Dept Precis Machinery & Precis Instrumentat Hefei Peoples R China Univ Calif Los Angeles Dept Phys & Astron Los Angeles CA USA Calif State Univ East Bay Dept Phys Hayward CA USA Inst for Basic Sci Korea Ctr Axion & Precis Phys Res Daejeon South Korea Korea Adv Inst Sci & Technol Dept Phys Daejeon South Korea Twinleaf LLC Plainsboro NJ USA Univ Sci & Technol China Hefei Natl Lab Phys Sci Microscale Hefei Peoples R China Jagiellonian Univ Inst Phys Krakow Poland Oberlin Coll Dept Phys & Astron Oberlin OH USA Univ Minnesota Sch Phys & Astron Minneapolis MN USA Univ Minnesota William I Fine Theoret Phys Inst Sch Phys & Astron Minneapolis MN USA Leibniz Inst Photon Technol Jena Germany Bucknell Univ Dept Phys & Astron Lewisburg PA 17837 USA Princeton Univ Dept Phys Princeton NJ 08544 USA Tech Univ Munich Garching Germany Univ Waterloo Dept Phys & Astron Waterloo ON Canada Univ Colorado NIST JILA Boulder CO 80309 USA Univ Colorado Dept Phys Boulder CO 80309 USA Harvard Univ Dept Phys Cambridge MA 02138 USA

Ultralight bosons such as axion-like particles are viable candidates for dark matter. They can form stable, macroscopic field configurations in the form of topological defects that could concentrate the dark matter density into many distinct, compact spatial regions that are small compared with the Galaxy but much larger than the Earth. Here we report the results of the search for transient signals from the domain walls of axion-like particles by using the global network of optical magnetometers for exotic (GNOME) physics searches. We search the data, consisting of correlated measurements from optical atomic magnetometers located in laboratories all over the world, for patterns of signals propagating through the network consistent with domain walls. The analysis of these data from a continuous month-long operation of GNOME finds no statistically significant signals, thus placing experimental constraints on such dark matter scenarios. A search for transient dark matter in the form of domain walls of axion-like particles finds no statistically significant signal. This places constraints on our theoretical understanding of such scenarios.

关键词： Atomic and molecular physics Dark energy and dark matter Particle physics Physics general Theoretical Mathematical and Computational Physics Classical and Continuum Physics Atomic Molecular Optical and Plasma Physics Condensed Matter Physics Complex Systems

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A split cytosine deaminase architecture enables robust inducible base editing

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FASEB JOURNAL 2021年第12期35卷 e22045-e22045页

作者： Long, Jie Liu, Nan Tang, Wenling Xie, Lifang Qin, Fengming Zhou, Lifang Tao, Rui Wang, Yanhong Hu, Yun Jiao, Yaoge Li, Li Jiang, Lurong Qu, Junyan Chen, Qiang Yao, Shaohua Sichuan Univ West China Hosp Canc Ctr Lab BiotherapyNatl Key Lab Biotherapy Renmin Nanlu 17 Chengdu 610041 Peoples R China Sichuan Univ Coll Life Sci Chengdu Peoples R China Sichuan Univ West China Hosp Ctr Infect Dis Chengdu Peoples R China

Directed base substitution with base editing technology enables efficient and programmable conversion of C:G or A:T base pairs to T:A or G:C in the genome. Although this technology has shown great potentials in a variety of basic research, off-target editing is among one of the biggest challenges toward its way to clinical application. Base editing tools, especially the tools converting C to T, caused unpredictable off-target editing throughout the genome, which raise the concern that long-term application of these tools would induce genomic instability or even tumorigenesis. To overcome this challenge, we designed an inducible base editing tool that was active only in the presence of a clinically safe chemical, rapamycin. In the guidance of structural information, we designed four split-human APOBEC3A (A3A) -BE3 base editors in which these A3A deaminase enzymes were split at sites that were opposite to the protein-nucleotide interface. We showed that by inducible deaminase reconstruction with a rapamycin responsible interaction system (FRB and FKBP);three out of four split-A3A-derived base editors showed robust inducible base editing. However, in the absence of rapamycin, their editing ability was dramatically inhibited. Among these split editors, splicing at Aa85 of A3A generated the most efficient inducible editing. In addition, compared to the full-length base editor, the splitting did not obviously alter the editing window and motif preference, but slightly increased the product purity. We also expanded this strategy to another frequently used cytosine deaminase, rat APOBEC1 (rA1), and observed a similar induction response. In summary, these results demonstrated the concept that splitting deaminases is a practicable method for timely controlling of base editing tools.

关键词： base editing CRISPR Cas9 cytosine deaminase FRB FKBP protein split

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An ACL reconstruction robotic positioning system based on anatomical characteristics

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INTERNATIONAL JOURNAL OF ADVANCED ROBotIC SYSTEMS 2020年第1期17卷

作者： Guo, Na Wang, Tianmaio Wei, Min Hu, Lei Liu, Hongsheng Wang, Yuhan Yang, Biao Yu, Guoxin Beihang Univ Sch Mech Engn & Automat Beijing Peoples R China Chinese Peoples Liberat Army Gen Hosp Dept Orthopaed Beijing 100853 Peoples R China Beihang Univ Beijing Adv Innovat Ctr Biomed Engn Beijing Peoples R China

To improve the positioning accuracy of tunnels for anterior cruciate ligament (ACL) reconstruction, we proposed an ACL reconstruction robotic positioning system based on anatomical characteristics. The system includes a preoperative path planning system, an intraoperative path planning system, and a navigation and positioning system. Brahmet line, anterior, and posterior cortical lines are used for registration of preoperative computed tomography (CT) images and intraoperative X-ray images. A new calibrator of C-arm is applied to establish the mapping between medical images and surgical space. Tunnels for ACL reconstruction can be built anatomically by the robot. The accuracy of the path planning system is 1.73 mm in the four dry bones experiments and 2.17 mm in the two cadaver experiments. The accuracy meets the accuracy requirement of ACL construction surgery.

关键词： ACL reconstruction surgical robot anatomical characteristics

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Over expression of TaFer gene from Tamarix androssowii improves iron and drought tolerance in transgenic Populus tomentosa

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Journal of Forestry research 2019年第1期30卷 171-181页

作者： Bo Zhao Jingli Yang Wenjing Yao Boru Zhou Wei Zheng Tingbo Jiang State Key Laboratory of Tree Genetics and Breeding Northeast Forestry University Department of Pharmacy Heilongjiang University of Chinese Medicine Research Center on Life Sciences and Environmental Sciences Harbin University of Commerce

Ferritin, a universal intracellular protein, can store large amounts of iron and improve plant resistance to abiotic and biotic stress. In this study, a ferritin gene(TaFer) from Tamarix androssowii Litv. was transferred into Populus tomentosa Carr. cv 'BJR01' via Agrobacterium. Six independent transgenic lines were obtained with a tolerance to kanamycin and three were randomly selected for further analysis. The PCR and RT-PCR results indicate that the TaFer gene had been integrated into the poplar genome. The effect of the gene on abiotic stress tolerance was tested, and the results show that transgenic plants improve growth, had higher chlorophyll and lower MDA contents, and higher relative electrical conductivity,fewer changes of SOD and POD activities, higher iron content, higher root ferric reductase activity and lower levels of ROS accumulation and cell death in response to drought, Fe-insufficient or Fe-excess tolerance. These results indicate that the TaFer gene can improve abiotic stress tolerance in transgenic Populus tomentosa.

关键词： Tarmarix andnssowii Ferritin Iron Genetic transformation Stress resistance

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Photon-limited imaging through scattering medium based on deep learning

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OPTICS EXPRESS 2019年第23期27卷 33120-33134页

作者： Sun, Lei Shi, Jianhong Wu, Xiaoyan Sun, Yiwei Zeng, Guihua Shanghai Jiao Tong Univ State Key Lab Adv Opt Commun Syst & Networks Ctr Quantum Sensing & Informat Proc Shanghai 200240 Peoples R China

Imaging under ultra-weak light conditions is affected by Poisson noise heavily. The problem becomes worse if a scattering media is present in the optical path. Speckle patterns detected under ultra-weak light condition carry very little information which makes it difficult to reconstruct the image. Off-the-shelf methods are no longer available in this condition. In this paper, we experimentally demonstrate the use of a deep learning network to reconstruct images through scattering media under ultra-weak light illumination. The weak light limitation of this method is analyzed. The random Poisson detection under weak light condition obtains partial information of the object. Based on this property, we demonstrated better performance of our method by enlarging the training dataset with multiple detections of the speckle patterns. Our results demonstrate that our approach can reconstruct images through scattering media from close to 1 detected signal photon per pixel (PPP) per image. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

关键词： Image processing Image quality Image quality assessment Medical imaging Scattering media Speckle patterns

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