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Ionization and Fragmentation of Butanone Clusters Irradiated by Photons at 355 and 118 nm

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Chemical Research in Chinese Universities 2011年第3期27卷 508-511页

作者： SUN Chang-kai HU Zhan YANG Xue JIN Ming-xing HU wen-cheng ding Da-jun Institute of Atomic and Molecular Physics Jilin University Changchun 130012 P. R. China

Time-of-flight（TOF） mass spectra of molecular butanone clusters were measured under the irradiation of photons at 355 and 118 nm. Butanone molecular parent ion and several series of butanone cluster fragments such as （CH3COC2H5）nH＋, （CH3COC2H5）nC2H5＋, （CH3COC2H5）nCH3CO＋ and （CH3COC2H5）nC2H5CO＋ were observed. Odd-even variation pattern in the intensity of （CH3COC2H5）nCH3CO＋ is obvious from n=4 to 8. A connection is es-tablished between the fragment clusters （CH3COC2H5）nCH3CO＋ and the neutral clusters （CH3COC2H5）n＋1 based on the consideration of butanone cluster dissociation mainly by losing a radical C2H5？. The stability variation of the neutral clusters calculated via the HF-B3LYP method based on DFT is in agreement with the observed phenomena experimentally, indicating （CH3COC2H5）n＋1（n＋1=5,7） with a ring structure are with higher stability over the adjacent even-number clusters.

关键词： Cluster Ionization Fragment Butanone

The intricacies of neurotrophic factor therapy for retinal ganglion cell rescue in glaucoma: a case for gene therapy

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Neural Regeneration Research 2016年第6期11卷 875-877页

作者： Marianna Foldvari ding wen Chen School of Pharmacy Waterloo Institute of Nanotechnology and Center for Bioengineering and Biotechnology University of Waterloo

Regeneration of damaged retinal ganglion cells（RGC） and their axons is an important aspect of reversing vision loss in glaucoma patients. While current therapies can effectively lower intraocular pressure, they do not provide extrinsic support to RGCs to actively aid in their protection and regeneration. The unmet need could be addressed by neurotrophic factor gene therapy, where plasmid DNA, encoding neurotrophic factors, is delivered to retinal cells to maintain sufficient levels of neurotrophins in the retina. In this review, we aim to describe the intricacies in the design of the therapy including： the choice of neurotrophic factor, the site and route of administration and target cell populations for gene delivery. Furthermore, we also discuss the challenges currently being faced in RGC-related therapy development with special considerations to the existence of multiple RGC subtypes and the lack of efficient and representative in vitro models for rapid and reliable screening in the drug development process.

关键词： neurotrophic glaucoma ganglion RGCs retina intraocular Regeneration administration representative populations

Formalism of rotating-wave approximation in high-spin system with quadrupole interaction

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Chinese Physics B 2023年第3期32卷 72-78页

作者：丁文魁王晓光 Key Laboratory of Optical Field Manipulation of Zhejiang Province and Department of Physics Zhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Institute of Modern Physics and Department of Physics Zhejiang UniversityHangzhou 310027China Graduate School of China Academy of Engineering Physics Beijing 100193China

We investigate the rotating wave approximation applied in the high-spin quantum system driven by a linearly polarized alternating magnetic field in the presence of quadrupole *** conventional way to apply the rotating wave approximation in a driven high-spin system is to assume the dynamics being restricted in the reduced Hilbert ***,when the driving strength is relatively strong or the driving is off resonant,the leakage from the target resonance subspace cannot be neglected for a multi-level quantum *** propose the correct formalism to apply the rotating wave approximation in the full Hilbert space by taking this leakage into *** estimating the operator fidelity of the time propagator,our formalism applied in the full Hilbert space unambiguously manifests great advantages over the conventional method applied in the reduced Hilbert space.

关键词： rotating wave approximation quadrupole interaction high-spin system

Directed evolution of the fusion enzyme for improving astaxanthin biosynthesis in Saccharomyces cerevisiae

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Synthetic and Systems Biotechnology 2023年第1期8卷 46-53页

作者： Yong-wen ding Chuan-Zhen Lu Yan Zheng Han-Zhang Ma Jin Jin Bin Jia Ying-Jin Yuan Frontier Science Center for Synthetic Biology(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

catalyzed byβ-carotene hydroxylase(crtZ)andβ-carotene ketolase(crtW)decreases the content of the ***,we exploited directed evolution of the fusion of crtZ and crtW for improving astaxanthin biosynthesis in Saccharomyces *** results demonstrated that the fusion enzyme of crtZ-crtW with 2 X GGGGS peptides linker can effectively reduce the accumulation of intermediates and improves the content of *** with the control strain,the fusion enzyme of ketase and hydroxylase reduced zeaxanthin and canthaxanthin by 7 and 14 times and increased astaxanthin by 1.6 times,***,9 variant fusion mutants with improved astaxanthin production were generated through directed *** these dominant mutants generated a variant,L95S+I206L,which increased the astaxanthin content of 3.8 times than the control *** AlphaFold2 assisted structural analysis indicated that these two mutations alter the interaction between the substrate and the enzymes *** research provided an efficient idea to reduce the accumulation of the intermediate products in complex biosynthesis pathway.

关键词： Astaxanthin Directed evolution Fusion enzyme Saccharomyces cerevisiae Synthetic biology

Apportioning above-and below-ground effects of moss biocrusts on soil detachment by overland flow in a subtropical climate

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Journal of Mountain Science 2021年第10期18卷 2646-2655页

作者： ZHANG Guan-hua YI Liang ding wen-feng LEI Xu WANG Yi-ran SUN Bao-yang LI Jian-ming Soil and Water Conservation Department Changjiang River Scientific Research InstituteWuhan 430010China Research Center on Mountain Torrent&Geologic Disaster Prevention of Ministry of Water Resources Wuhan 430010China Central-Southern Safety&Environment Technology Institute Co. LtdWuhan 430071China

Biocrusts affect soil detachment through above-ground(top crust’s surface covering)and below-ground(sub-crust’s binding and bonding,B&B)effects,which might vary with biocrust development or ***,these effects in humid climates are still *** study was conducted to apportion and quantify the surface covering and B&B effects of moss biocrusts with five coverage levels(1%–20%,20%–40%,40%–60%,60%–80%,and 80%–100%)on soil detachment by overland flow in a subtropical humid *** treatments with one being intact moss crusts and one removing the aboveground moss tissues were designed for each coverage level,and bare soil was used as the *** results indicated that soil detachment capacity(Dc)and rill erodibility(Kr)decreased with biocrust *** removing the above-ground moss tissues,the impeding effect of biocrusts on soil detachment weakened,but still increasing soil erosion resistance relative to bare *** intact crust,Dc was reduced by 50%–95%compared with bare soil,wherein 36%–55%and 14%–40%were attributed to the surface covering and B&B,*** top crust contributed more than sub-crust to the soil detachment reduction,which were related to but not linear with biocrust *** biocrust coverage reached mid-to-higher level(40%–100%),both top crust and sub-crust steadily contributed to soil detachment reduction with 60%and 40%,*** findings advance a better understanding of the influencing mechanism of biocrusts on soil erosion in humid climates and highlight the importance of saving biocrusts as ecosystem functions.

关键词： Soil detachment Rill erodibility Effect apportionment Contribution rate Three Gorges

Comparative investigations of ternary thermite Al/Fe_(2)O_(3)/CuO and Al/Fe_(2)O_(3)/Bi_(2)O_(3) from pyrolytic,kinetics and combustion behaviors

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Defence Technology（防务技术） 2023年第8期26卷 180-190页

作者： Shi Li Jia-lin Chen Tao Guo wen ding Lin Jiang Miao Yao Jia-xing Song Li-feng Xie Yi-ming Mao College of Field Engineering Army Engineering University of PLANanjing210007China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China Xi'an Rare Metal Materials Research Institute Co. Ltd.Xi'an710016China

To develop new energy enhancement energetic materials with great combustion performance and thermal stability,two kinds of ternary thermite,Al/Fe_(2)O_(3)/CuO and Al/Fe_(2)O_(3)/Bi_(2)O_(3),were prepared and analyzed via mechanical ball *** samples were characterized by SEM,XRD,TG-DSC,constant volume and constant pressure combustion *** first exothermic peaks of Al/Fe_(2)O_(3)/CuO and Al/Fe_(2)O_(3)/Bi_(2)O_(3) appear at 579°C and 564.5°C,*** corresponding activation energies are *** corresponding mechanism functions are set as G(a) = [-ln(1-a)]^(3/4) and G(a) =[-ln(1-a)]2/3,respectively,which belong to the Avrami-Erofeev ***/Fe_(2)O_(3)/CuO has better thermal *** small dose samples,its critical temperature of thermal explosion is 121.05°C higher than that of Al/Fe_(2)O_(3)/Bi_(2)O_(3).During combustion,the flame of Al/Fe_(2)O_(3)/CuO is spherical,and the main products are FeAl_(2)O_(4) and *** flame of Al/Fe_(2)O_(3)/Bi_(2)O_(3)is jet-like,and the main products are Al_(2)O_(3),Bi and ***/Fe_(2)O_(3)/Bi_(2)O_(3)has better ignition and gas production *** average ignition energy is 4.2 J lower than that of Al/Fe_(2)O_(3)/*** average step-up rate is 28.29 MPa/s,which is much higher than 6.84 MPa/s of Al/Fe_(2)O_(3)/*** paper provides a reference for studying the thermal safety and combustion performance of ternary thermite.

关键词： Ternary thermite Thermal kinetics Reaction mechanism Combustion

Influence of σ^(* )and φ Mesons on (A) Hyperon ^(1)S_(0) Superfluidity in Neutron Star Matter

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Chinese Physics Letters 2012年第5期29卷 252-255页

作者： XU Yan LIU Guang-Zhou WANG Hong-Yan ding wen-Bo ZHAO En-Guang Changchun Observatory National Astronomical ObservatoriesChinese Academy of SciencesChangchun 130117 Center for Theoretical Physics Jilin UniversityChangchun 130012 Department of Physics Bohai UniversityJinzhou 121000 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190

Within the framework of the relativistic mean field theory,we investigate the ^(1)S_(0) superfluidity (SF) of A hyperons in neutron star (NS) matter including σ^(*) and φ *** energy gap of ∧ hyperons is calculated with the Nijmegen one-boson-exchange potentials for a (∧∧) pair. The parameter set we use is in line with the recent experimental data △B_(∧∧) ~ 1.01 ± 0.20_+0.18-0.11 *** is found that with σ^(*) and φ mesons the pairing energy gap △F of ∧ hyperons and the corresponding SF critical temperature T_(C∧) are *** addition the NS mass range of ∧ hyperon SF is enlarged obviously.

关键词： meson relativistic addition

Recent Advancements in Intestinal Microbiota Analyses:A Review for Non-Microbiologists

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Current Medical Science 2018年第6期38卷 949-961页

作者： Xiao-wei FENG wen-ping ding Ling-yun XIONG Liang GUO Jia-ming SUN Peng XIAO Department of Psychiatry Wuhan Youfu HospitalWuhan 430050China Department of Ultrasound Wuhan Women and Children's Health Care CenterWuhan 430016China Department of Plastic Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and Technology Wuhan 430022China

Microbial constituents naturally inhabiting the gastrointestinal tract may influence the homeostasis of the gut *** presence or overabundance of some bacterial taxa has been reported to be associated with complex diseases,and the metabolites of certain bacteria may contribute to diverse disorders by influencing signaling ***,the study of gut microbial population has emerged as a crucial field and a new potential area of clinical significance. Advances in the methods of microbiota analysis have shed light upon the details including species diversity,microfloral activities as well as the entire gut ***,comprehensive reviews on this subject are still *** elucidating the appropriate selection strategy of the methods to address a particular research question,we comprehensively reviewed the continuously improving technologies,classical to newly developed,and dissected their relative advantages and *** addition,aiming at the rapidly advancing next-generation sequencing,we enumerated the improvements in mainstream platforms and made the horizontal and vertical comparison among ***,we demonstrated the four main-omics methods,which may provide further mechanistic insights into the role of microbiota,to propel phylotyping analysis to functional analysis.

关键词： gut microbiota methods analysis advantages drawbacks

Can transcutaneous perianal ultrasonography be the first-line diagnostic instrument for evaluating pediatric perianal fistulas?

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Gastroenterology Report 2022年第1期10卷 559-565页

作者： Yu-wen ding Hao-Qiang Yin Hong-Tao Liang Jin-Gen Lu Bo Wang Chen Wang Department of Proctology Longhua Hospital affiliated to Shanghai University of TCMShanghaiP.R.China Department of Ultrasonic Longhua Hospital affiliated to Shanghai University of TCMShanghaiP.R.China Shanghai Shumiao Health Cloud Co.Ltd ShanghaiP.R.China

Background:Pediatric perianal fistula is a common *** is more difficult to detect the fistula tract and internal opening(IO)in children than in *** study aimed to evaluate the clinical diagnostic value of transcutaneous perianal ultrasound for children with perianal ***:A retrospective review was conducted by analysing the preoperative transcutaneous perianal ultrasound and intraoperative exploration results of 203 consecutive patients who were<3 years old and diagnosed with perianal *** were conducted to evaluate the accuracy and consistency of utilizing the transcutaneous perianal ultrasound in the diagnosis of the complexity and location of the IO of perianal ***:Compared with intraoperative exploration,the preoperative transcutaneous perianal ultrasonography has almost perfect agreement(Kappa=0.881,P<0.001)in the diagnosis of fistula tract complexity and IO with a sensitivity of 92%and a specificity of 97%.In addition,both intraoperative exploration and transcutaneous perianal ultrasound diagnosis showed high consistency in the identification of the IO of perianal fistulas(QuadrantⅠKappa=0.831,QuadrantⅡKappa=0.773,QuadrantⅢKappa=0.735,QuadrantⅣKappa=0.802,all P<0.01).The IOs were mainly distributed in QuadrantsⅣandⅡin both simple and complex ***:Transcutaneous perianal ultrasound,as a non-invasive and simple imaging technique,showed high accuracy in the diagnosis and identification of the fistula classification and IO *** could be considered a first-line diagnostic instrument for evaluating perianal fistulas among children.

关键词： pediatric perianal fistula transcutaneous perianal ultrasound surgical exploration consistency