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Chinese Journal of Chemical Physics 2008年第3期21卷 193-201页

作者： Xi xing Beth Reed Mi Kyung Bahng Peng Wang Hin Koo Woo Sun Jong Baek Chee sh.ng Lain Cheuk Yiu ng Department of Chemistry University of California Davis Davis California 95616 USA

We sh.w that by scanning the frequency of a single mode infrared （IR） optical parametric oscillator （IR- OPO） laser to excite the molecular species of interest and fixing the frequency of a vacuum ultraviolet （VUV） laser to photoionize the IR excited species, high-resolution IR spectra of polyatomic neutrals can be obtained with high sensitivity. The fact that this IR-VUV-photoion （IR-VUV-PI） method is based on VUV photoionization probe, and thus, allows the identification of the neutral IR absorber, makes it applicable for IR spectroscopy measurements of isotopemers, radicals, and clusters, which usually exist as impure samples. The highly resolved IR-VUV-PI measurements achieved using the single mode IR-OPO laser have made possible the selection of single rovibrational states of CH3X （X=Br and I）, C2H4, and C3H4 for VUV-pulsed field ionization-photoelectron （VUV-PFI-PE） measurements, resulting in rovibrationally resolved photoelectron spectra for these polyatomic molecules. These experiments sh.w that the signal- to-noise ratios of the IR-VUV-PI and IR-VUV-PFI-PE spectra obtained by employing the high-resolution IR-OPO laser are significantly higher than those observed in previous IR-VUV-PI and IR-VUV-PFI-PE studies using a low-resolution IR-OPO laser. Further improvement in sensitivity of IR-VUV-PI and IR- VUV-PFI-PE measurements by using the collinear arrangement of IR-VUV lasers and molecular beam is discussed.

关键词： Vacuum ultraviolet Infrared Pulse-field photoelectron High resolution

Performance of a small AT-TPC prototype

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Nuclear Science and Techniques 2018年第7期29卷 138-144页

作者： Jin-Yan Xu Qi-Te Li Yan-Lin Ye Jian Gao Jia-xing Han sh.-Wei Bai Ka-Hou ng School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University

A small prototype of an active-target time projection chamber detector based on the gas electron multiplier(GEM) readout technique was designed and *** calculations were performed to analyze the electric field distribution and optimize the *** particular,a guard ring installed above the GEM foil may play an important role in sh.ping the electric field in the gas vessel and improving the overall performance of the *** best results were obtained at a guard-ring voltage of-950 *** using a collimated a-particle source,an energy resolution of 3.6–4.0 ke V can be achieved for deposited energies of 18–21 keV,respectively.A position resolution of less 0.2 mm was observed along the electron drift direction,whereas the resolution in the readout plane was approximately 0.45 mm.A time resolution of less than 20 ns was *** using helium as the primary working gas as well as the target material,a t a elastic scattering events can be clearly imaged.

关键词：原型性能优化设计模拟计算工作气体宝石时间电子

Prevalence and risk factors of depression among patients with perianal fistulizing Crohn’s disease

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World Journal of Psychiatry 2024年第5期14卷 715-725页

作者： Jing Li Wing-Yi ng Li-Chao Qiao Fen Yuan xing Lan Li-Bei zhu Bo-Lin Yang zh.ng-Qiu Wang Department of Radiology Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Acupuncture and Rehabilitation Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Colorectal Surgery Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina

BACKGROUND Psychological distress,especially depression,associated with perianal fistulizing Crohn’s disease(PFCD)is widespread and ***,there is a surprising paucity of studies to date that have sought to identify the prevalence and risk factors of depression associated with *** To estimate the prevalence of depressive symptoms and investigate the depression-related risk factors in patients with *** The study was conducted in the form of survey and clinical data collection via questionnaire and specialized medical *** symptoms,life quality,and fatigue severity of patients with PFCD were assessed by Patient Health Questionnaire-9,Inflammatory Bowel Disease Patient Quality of Life Questionnaire(IBDQ),and Inflammatory Bowel Disease(IBD)Fatigue Patient Self-assessment *** basic demographic information,overall disease features,perianal clinical information,and laboratory inflammation indicators were also *** regression analysis was ultimately used to ascertain the risk factors of depression associated with *** A total of 123 patients with PFCD were involved,and 56.91%were suffering from *** to multivariate logistic regression analysis,Perianal Disease Activity Index(PDAI)score[odds ratio(OR)=0.69,95%confidence interval(CI):0.50 to 0.95],IBDQ score(OR=0.93,95%CI:0.88 to 0.97),modified Van Assche index(OR=1.24,95%CI:1.01 to 1.53),and IBD Fatigue score(OR=1.72,95%CI:1.23 to 2.42)were independent risk factors of depression-related prevalence among patients with PFCD(Png perianal modified Van Assche index(βvalue=0.166,95%CI:0.02 to 0.31)and decreasing IBDQ score(βvalue=-0.116,95%CI:-0.14 to-0.09)were independently associated with the severity of depression(P<0.05).CONCLUSION Depressive symptoms in PFCD patients have significantly high *** score,modified Van Assche index,quality of life,and fatigue severity

关键词： Crohn’s disease Fistula Depression Inflammatory bowel diseases Risk factors

Origins of Terrestrial Organic Matter in Surface Sediments of the East China Sea sh.lf

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Journal of Ocean University of China 2017年第5期16卷 793-802页

作者： zh.ng Hailong xing Lei zhAO Meixun Key Laboratory of Marine Chemistry Theory and Technology(Ocean University of China) Ministry of Education/Qingdao Collaborative Innovation Center of Marine Science and TechnologyQingdao 266100P.R.China Institute of Marine Organic Geochemistry Ocean University of ChinaQingdao 266100P.R.China

Terrestrial organic matter(TOM) is an important component of marine sedimentary OM, and revealing the origins and transport mechanisms of TOM to the East China Sea(ECS) is important for understanding regional carbon cycle. A novel approach combining molecular proxies and compound-specific carbon isotopes is used to quantitatively constrain the origins and transport mechanisms of TOM in surface sediments from the ECS sh.lf. The content of terrestrial biomarkers of(C_(27)+C_(29)+C_(31)) n-alkanes(52 to 580 ng g^(-1)) revealed a seaward decreasing trend, the δ^(13)CTOC values(-20.6‰ to-22.7‰) were more negative near the coast, and the TMBR(terrestrial and marine biomarker ratio) values(0.06 to 0.40) also revealed a seaward decreasing trend. These proxies all indicated more TOM(up to 48%) deposition in the coastal areas. The Alkane Index, the ratio of C_(29)/(C_(29)+C_(31)) n-alkanes indicated a higher proportion of grass vegetation in the coastal area; While the δ13C values of C_(29) n-alkane(-_(29).3‰ to-33.8‰) indicated that terrestrial plant in the sediments of the ECS sh.lf were mainly derived from C_3 plants. Cluster analysis afforded detailed estimates of different-sourced TOM contributions and transport mechanisms. TOM in the zhejiang-Fujian coastal area was mostly delivered by the Changjiang River, and characterized by higher %TOM(up to 48%), higher %C_3 plant OM(68%-85%) and higher grass plant OM(56%-61%); TOM in the mid-sh.lf area was mostly transported by aerosols, and characterized by low %TOM(less than 17%), slightly lower C_3 plant OM(56%-72%) and lower grass plant OM(49%-55%).

关键词： alkanes coastal terrestrial sh.lf sedimentary mostly aerosols vegetation quantitatively decreasing

Constructing quasi-random subsets of Z_N by using elliptic curves

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Applied Mathematics(A Journal of Chinese Universities) 2012年第1期27卷 105-113页

作者： LIN zhi-xing CHEN zhi-xiong Department of Mathematics Putian UniversityPutianFujian 351100China State Key Laboratory of Information Security Institute of SoftwareChinese Academy of SciencesBeijing 100049China

Let ε ： y^2 = x3 ＋ Ax ＋ B be an elliptic curve defined over the finite field Zp（p 〉 3） and G be a rational point of prime order N on ε. Define a subset of ZN, the residue class ring modulo N, asS：={n：n∈ZN,n≠0,（X（ng）/p）=1} where X（ng） denotes the x-axis of the rational points nC and （＊/P） is the Legendre symbol. Some explicit results on quasi-randomness of S are investigated. The construction depends on the intrinsic group structures of elliptic curves and character sums along elliptic curves play an important role in the proofs.

关键词： elliptic curve quasi-random subset quasi-randomness character sum Legendre symbol.

Reproductive polyphenism and its advantages in aphids:Switching between sexual and asexual reproduction

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Journal of Integrative Agriculture 2020年第6期19卷 1447-1457页

作者： YAN sh.o WAng Wan-xing sh.N Jie Department of Entomology/MOA Key Lab of Pest Monitoring and Green Management College of Plant ProtectionChina Agricultural UniversityBeijing 100193P.R.China Key Lab of Biology and Genetic Improvement of Root and Tuber Crops Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing 100081P.R.China

Reproductive polyphenism,which allows one genotype to produce sexual and asexual morphs,is an extreme case of phenotypic plasticity and is commonly observed in *** are typical species that switch these reproductive modes,and the pathway orientation is triggered by the environmental conditions(mainly photoperiod and temperature).The typical arm ual life of aphids in eludes a successi on of parthenogenetic gen erations duri ng the spri ng and summer and a single sexual generation in *** this review,we describe how the environmental cues orientate the reproductive mode of aphids from photoperiodic perception to endocrine regulation,and how juvenile hormones may act on the target cells(oocytes)to initiate the gametogenesis and embryogenesis in sexual and asexual *** also discuss the paradox of sex,especially the advantages of sexual reproduction in *** the recent development of genomic resources in aphids,many potential genes involved in the reproductive polyphenism will enter the public's *** particular,we describe a novel RNAi method in aphids,which may provide a molecular technique for determining the developmental fate and multiple reproductive strategies.

关键词： aphids parthenogenesis embryogenesis gametogenesis photoperiodism

化氓兴边:乾隆朝西宁府的治边逻辑与历史经验

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青海民族研究 2018年第3期29卷 132-139页

作者：张兴年青海民族大学青海西宁810007

历代边远少数民族能欣然向化,归附中央王朝,这是无数统治者虽殚精竭力而不可得的盛世图景。纵观乾隆一朝,西宁边口地带非但没有出现大的社会动荡,反而成为清代治边的成功典范。究其缘由,边疆大吏的治边理念是否合乎历史规律,其举措能否... 详细信息

历代边远少数民族能欣然向化,归附中央王朝,这是无数统治者虽殚精竭力而不可得的盛世图景。纵观乾隆一朝,西宁边口地带非但没有出现大的社会动荡,反而成为清代治边的成功典范。究其缘由,边疆大吏的治边理念是否合乎历史规律,其举措能否抓住治边要害等关系殊甚。其时,西宁府"一线东通,三面外暴",商旅常遭劫掠,百姓不得安宁。然而经历西宁府整饬武备、编户齐民、设厅置县、垦恤民瘼、倡儒化俗等一系列兴边举措,不断开拓,最终在边口"辟榛莽为良田,化干戈以玉帛",其所蕴含的安氓、化氓等治边逻辑与历史经验不可不察。

关键词：西宁府化氓治边历史经验

Synchronous detection of glutathione/hydrogen peroxide for monitoring redox status in vivo with a ratiometric upconverting nanoprobe

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Nano Research 2019年第4期12卷 931-938页

作者： Judun zh.ng Yunxia Wu Da xing Tao zh.ng MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science South China Normal University Guangzhou 510631 China College of Biophotonics South China Normal University Guangzhou 510631 China

Cellular redox status presents broad implications with diverse physiological and pathological processes. Simultaneous detection of both the oxidative and reductive species of redox couples, especially the most representative pair glutathione/hydrogen peroxide (Gsh.H2O2), is crucial to accurately map the cellular redox status. However, it still remains challenging to synchronously detect Gsh.H2O2 in vivo due to lack of a reliable measuring tool. Herein, a ratiometric nanoprobe (UCNP-TB) possessing simultaneous delectability of Gsh.H2O2 is establish.d based on a multi-spectral upconverti ng nano phosphor (UCNP-OA) as the lumin esce nee res onance energy tran sfer (LRET) donor and two dye molecules as the acceptors, including a Gsh.sensitive dye (TCG) and a H2O2-sensitive dye (BCH). With the as-prepared UCNP-TB, real-time and synchronous monitoring the variation of Gsh.and H2O2 in vitro and in living mice can be achieved using the ratio of the upcon versi on lumin esce nee (UCL) at 540 and 650 nm to that at 800 nm as the detecti on sign al, respectively, providi ng highly inhere nt reliability of the sensing results by self-calibrati on. Moreover, the nan oprobe is capable of mappi ng the redox status within the drug-resista nt tumor and the drug-induced hepatotoxic liver via ratiometric UCL imaging. Thus, this nan oprobe would provide a reliable tool to elucidate the redox state in vivo.

关键词： redox status glutathione hydrogen peroxide upconversion imaging nanoprobe

Littlest Higgs Model and Higgs Boson Associated Production with Top Quark Pair at High Energy Linear e^＋e^- Collider

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Communications in Theoretical Physics 2006年第3期45卷 511-516页

作者： YUE Chong-xing WAng Wei zh.ng Feng Department of Physics Liaoning Normal University Dalian 116029 China

In the parameter space allowed by the electroweak precision measurement data, we consider the contributions of the new particles predicted by the littlest Higga model to the Higgs hoson associated production with top quark pair in the future high energy linear e^＋e^- collider （ILU）. We find that the contributions mainly come from the new gauge bosons zh and BH. For reasonable values of the free parameters, the absolute value of the relative correction parameter δσ/σ^SM can be signiticanly large, which might be observed in the future ILU experiment with √S = 800 GeV.

关键词： littlest Higgs model Higgs boson new gauge bosons

Determination of Biotin in Pharmaceutical Formulations by Potassium Permanganate-luminol-CdTe Nanoparticles Chemiluminescence System

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Chemical Research in Chinese Universities 2012年第4期28卷 604-608页

作者： TRAORE Zoumana Sékou SU xing-guang College of Chemistry Jilin University

A sensitive flow-injection chemiluminescence method was developed for the determination of biotin in the pharmaceutical *** affinity between avidin and biotin was used to adsorb biotin on the polystyrene,with subsequent quantification of biotin based on its ability to enhance the chemiluminescence（CL） signal generated by the redox reaction of potassium permanganate-luminol-CdTe nanoparticles CL *** investigations prove that apart from 3-aminophthalate,the CdTe quantum dots（QDs） play both catalytic and emitter *** optimum conditions,the linear range for the determination of biotin was 0.01―25 ng/mL with a detection limit of 7.3×10-3 ng/mL（S/N=3）.The relative standard deviation of 5 ng/L biotin was 2.06%（n=7）.The proposed method was used to determine the biotin concentration in the pharmaceutical formulations and the recovery was between 96.4% and 104%.The proposed method is simple,convenient,rapid and sensitive.

关键词： Flow-injection Chemiluminescence Biotin CdTe nanoparticle