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Journal of Chinese Pharmaceutical Sciences 2018年第3期27卷 201-208页

作者： Dan Huang Daolin Zhang Nana Wang Xinhui Jiang school of pharmacy Chongqing Medical University Yuzhong District Chongqing 400016 China Chongqing Pharmaceutical Research Institute Co. Chongqing Engineering Research Center for Chemical Pharmaceutical Nan＇an District Chongqing 400016 China luohe third People＇s Hospital of Henan Province Luohe Henan 462000 China

A simple and effective high-performance liquid chromatography with ultraviolet detection（HPLC-UV） method was established to determine entecavir optical isomers. With 3 chiral carbon atoms, entecavir had 7 optical isomers, including 6 diastereoisomers and 1 enantiomer. The separations were performed on a Symmetrix ODS-AQ C_（18） column（4.6 mm×250 mm, 5 μm） and a Daicel CHIRALPAK AD column（4.6 mm×250 mm, 10 μm）, respectively. The detection wavelength was set at 254 nm. The limit of detection（LOD） and the limit of quantification（LOQ） of diastereoisomers（diastereoisomer-1, diastereoisomer-2, diastereoisomer-3） were 0.0371, 0.0376, 0.0377, and 0.124, 0.125, 0.126 μg/mL, respectively. The LOD and LOQ of enantiomer were 0.14 and 0.46 μg/mL, respectively. The precision was within 0.36%, 0.44%, 1.04%, and 0.67% for diastereoisomer-1, diastereoisomer-2, diastereoisomer-3, and enantiomer, respectively. The recoveries of enantiomers ranged from 98.4% to 100.5%. The method could be applied to control the quality of entecavir.

关键词： Entecavir Chiral separation Diastereoisomers Enantiomer HPLC-UV

Bipartite Consensus of Discrete-Time Double-Integrator Multi-Agent Systems with Measurement Noise

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Journal of Systems Science & Complexity 2018年第6期31卷 1525-1540页

作者： MA Cuiqin ZHAO Weiwei ZHAO Yunbo school of Mathematical Sciences Qufu Normal UniversityQufu 273165China. No.1senior Middle school of Qufu Qufu 273165China College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

The effects of measurement noise are investigated in the context of bipartite consensus of multi-agent systems. In the system setting, discrete-time double-integrator dynamics are assumed for the agent, and measurement noise is present for the agent receiving the state information from its neighbors. Time-varying stochastic bipartite consensus protocols are designed in order to lessen the harmful effects of the noise. Consequently, the state transition matrix of the closed-loop system is analyzed, and sufficient and necessary conditions for the proposed protocol to be a mean square bipartite consensus protocol are given with the help of linear transformation and algebraic graph theory. It is proven that the signed digraph to be structurally balanced and having a spanning tree are the weakest communication assumptions for ensuring bipartite consensus. In particular, the proposed protocol is a mean square bipartite average consensus one if the signed digraph is also weight balanced.

关键词： Bipartite consensus discrete-time double-integrator measurement noise multi-agent systems

Geometry of Rectangular Block Triangular Matrices

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2035-2054页

作者： Li Ping HUANG Su Wen ZOU school of Mathematics and Computing Science Changsha University of Science and Technology Changsha 410076 P. R. China Liuzhou senior High school Liuzhou 545006 P. R. China

Let D be any division ring, and let T（mi,ni,k） be the set of k × k （k ≥ 2） rectangular block triangular matrices over D. For A, B ∈ T（mi,ni,k）, if rank（A - B） = 1, then A and B are said to be adjacent and denoted by A -B. A map T ： T（mi,ni,k） -〉 T（mi,ni,k） is said to be an adjacency preserving map in both directions if A - B if and only if φ（A） φ（B）. Let G be the transformation group of all adjacency preserving bijections in both directions on T（mi,ni,k）. When m1,nk ≥ 2, we characterize the algebraic structure of G, and obtain the fundamental theorem of rectangular block triangular matrices over D.

关键词： geometry of matrices triangular matrix adjacency preserving maximal set

Multiscale tensegrity model for the tensile properties of DNA nanotubes

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Applied Mathematics and Mechanics(English Edition) 2023年第3期44卷 397-410页

作者： Hanlin LIU Nenghui ZHANG Wei LU Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Qishuyan senior High school of Changzhou Changzhou 213000Jiangsu ProvinceChina

DNA nanotubes(DNTs)with user-defined shapes and functionalities have potential applications in many *** far,compared with numerous experimental studies,there have been only a handful of models on the mechanical properties of such *** paper aims at presenting a multiscale model to quantify the correlations among the pre-tension states,tensile properties,encapsulation structures of DNTs,and the surrounding ***,by combining a statistical worm-like-chain(WLC)model of single DNA deformation and Parsegian's mesoscopic model of DNA liquid crystal free energy,a multiscale tensegrity model is established,and the pre-tension state of DNTs is characterized theoretically for the first ***,by using the minimum potential energy principle,the force-extension curve and tensile rigidity of pre-tension DNTs are ***,the effects of the encapsulation structure and surrounding factors on the tensile properties of DNTs are *** predictions for the tensile behaviors of DNTs can not only reproduce the existing experimental results,but also reveal that the competition of DNA intrachain and interchain interactions in the encapsulation structures determines the pre-tension states of DNTs and their tensile *** changes in the pre-tension states and environmental factors make the monotonic or non-monotonic changes in the tensile properties of DNTs under longitudinal loads.

关键词： DNA nanotube(DNT) multiscale model tensegrity structure pre-tension state tensile property

Male circumcision： towards a World Health Organisation normative practice in resource limited settings

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Asian Journal of Andrology 2010年第5期12卷 628-638页

作者： Tim Hargreave senior Fellow School of Clinical Science Edinburgh University Scotland UK Technical Adviser to the WHO RHR -HRP Africa HIV Prevention Male Circumcision Programme

There is now grade 1 evidence that male circumcision （MC） reduces the risk of a man acquiring HIV. Modelling studies indicate MC could in the next 10 years save up to 2 million lives in those African countries with high HIV prevalence. Several African countries are now scaling up public health MC programmes. The most effective immediate public health MC programmes in Africa will need to target 18-20 years old men. In the longer term there is a need for infant circumcision programmes. In order to implement more widespread MC there is a need to make the surgical procedures as simple as possible so that safe operations can be performed by paramedical staff. The WHO Manual of Male Circumcision under local anaesthetic was written with these objectives in mind. Included in the manual are three adult techniques and four paediatric procedures. The adult procedures are the dorsal slit, the for- ceps guided and the sleeve resection methods. Paediatric methods included are the plastibell technique, the Mogen and Gomco shield method and a standard surgical dorsal slit procedure. Each method is described in a step by step manner with photographic and line drawing illustrations. In addition to the WHO manual of surgical technique a teaching course has been developed and using this course it has been possible in one week to train a circumcision surgeon who has had no or minimal previous surgical experience. Further scaling will require training of circumcision surgeons, monitoring performance, training the trainer workshops as well as advocacy at national, international and government meetings. In addition to proceeding with standardised methods work is in progress to assess novel techniques in adults such as stay on ring devices and policies are being formulated as to how to assess new devices. Also work is in progress to explore efficiencies in surgical processing by task sharing. Proper informed consent and safety remain paramount and great care has to be taken as programmes in

关键词： Africa HIV male circumcision

Influence of hypoxia on retinal progenitor and ganglion cells in human induced pluripotent stem cell-derived retinal organoids

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国际眼科杂志:英文版 2023年第10期16卷 1574-1581页

作者： Jin-Lin Du Li-Xiong Gao Tao Wang Zi Ye Hong-Yu Li Wen Li Quan Zeng Jia-Fei Xi Wen Yue Zhao-Hui Li Medical school of Chinese PLA Beijing 100853China senior Department of Ophthalmology the Third Medical Center of Chinese PLA General HospitalBeijing 100039China Departement of Ophthalmology the 6^(th)Medical Center of PLA General HospitalBeijing 100048China Stem Cell and Regenerative Medicine Lab Beijing Institute of Radiation MedicineBeijing 100850China

AIM:To observe the effect of low oxygen concentration on the neural retina in human induced pluripotent stem cell(hiPSC)-derived retinal organoids(ROs).METHODS:The hiPSC and a three-dimensional culture method were used for the *** embryoid bodies(EBs)were randomly and equally divided into hypoxic and normoxic *** of the EBs were taken on days 38,45,and 52,and the corresponding volume of EBs was ***,samples were collected at these three timepoints,followed by fixation,sectioning,and ***:The proportion of Ki67-positive proliferating cells increased steadily on day 38;this proliferationpromoting effect tended to increase tissue density rather than tissue *** days 45 and 52,the two groups had relatively similar ratios of Ki67-positive *** immunofluorescence analysis showed that the ratio of SOX2-positive cells significantly increased within the neural retina on day 52(P0.05).Moreover,the proportion of PAX6-/TUJ1+cells within the neural retinas increased considerably(P<0.01,<0.05,<0.05 respectively).CONCLUSION:Low oxygen promotes stemness and proliferation of neural retinas,suggesting that hypoxic conditions can enlarge the retinal progenitor cell pool in hiPSC-derived ROs.

关键词： hypoxia retinal organoid retinal progenitor cells retinal ganglion cells

Structure of Strict Abundant Semigroups

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Algebra Colloquium 2019年第3期26卷 387-400页

作者： Yizhi Chen Bo Yang Aiping Gan school of Mathematics and Big Data Huizhou University HuizhouGuangdong 516007China No.1 senior school of Liantang Nanchang 330200China College of Mathematics and Information Science Jiangxi Normal University Nanchang 330022China

We introduce a new class of semigroups called strict abundant semigroups,which are concordant semigroups and subdirect products of completely-J*-simple abundant semigroups and completely-J*-simple primitive abundant semigroups.A general construction and a tree structure of such semigroups are ***,the corresponding structure theorems for strict regular semigroups given by Auinger in 1992 and by Grillet in 1995 are generalized and ***,an example of strict abundant semigroups is also given.

关键词： structure regular semigroup strict regular semigroup abundant semigroup strict abundant semigroup

Mathematical Modeling of Moored Ship Motion in Arbitrary Harbor utilizing the Porous Breakwater

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China Ocean Engineering 2023年第5期37卷 738-752页

作者： Prachi Priya Prashant Kumar Gulshan Rajni Government Model Sanskriti senior Secondary school Ganaur Sonipat 131101India Department of Applied Sciences(Mathematics) National Institute of TechnologyDelhi 110036India JindalGobal Business school O.P.Jindal Global UniversitySonepat 131001India

The motion of the moored ship in the harbor is a classical hydrodynamics problem that still faces many challenges in naval operations,such as cargo transfer and ship pairings between a big transport ship and some small ships.A mathematical model is presented based on the Laplace equation utilizing the porous breakwater to investigate the moored ship motion in a partially absorbing/reflecting *** motion of the moored ship is described with the hydrodynamic forces along the rotational motion(roll,pitch,and yaw)and translational motion(surge,sway,and heave).The efficiency of the numerical method is verified by comparing it with the analytical study of Yu and Chwang(1994)for the porous breakwater,and the moored ship motion is compared with the theoretical and experimental data obtained by Yoo(1998)and Takagi et al.(1993).Further,the current numerical scheme is implemented on the realistic Visakhapatnam Fishing port,India,in order to analyze the hydrodynamic forces on moored ship motion under resonance *** model incorporates some essential strategies such as adding a porous breakwater and utilizing the wave absorber to reduce the port’s *** has been observed that these tactics have a significant impact on the resonance inside the port for safe maritime ***,the current numerical model provides an efficient tool to reduce the resonance within the arbitrarily shaped ports for secure anchoring.

关键词： boundary element method Laplace equation porous breakwater partially reflecting/absorbing harbor wall moored ship motion

Presurgical structural imaging and clinical outcome in combined bed nucleus of the stria terminalis-nucleus accumbens deep brain stimulation for treatment-resistant depression

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General Psychiatry 2024年第3期37卷 412-421页

作者： Fengting Wang Lulin Dai Tao Wang Yingying Zhang Yuhan Wang Yijie Zhao Yixin Pan Liuguan Bian Dianyou Li Shikun Zhan Yijie Lai Valerie Voon Bomin Sun Department of Neurosurgery Shanghai Jiao Tong University Medical School Affiliated Ruijin HospitalShanghaiChina Department of Psychiatry Zhejiang University School of Medicine Sir Run Run Shaw HospitalHangzhouChina Fudan University Institute of Science and Technology for Brain-inspired Intelligence ShanghaiChina Clinical Research Center for Mental Disorders Shanghai Pudong New Area Mental Health CenterShanghaiChina Department of Psychiatry University of CambridgeCambridgeUK

Background Structural imaging holds great potential for precise targeting and stimulation for deep brain stimulation(DBS).The anatomical information it provides may serve as potential biomarkers for predicting the efficacy of DBS in treatment-resistant depression(TRD).Aims The primary aim is to identify preoperative imaging biomarkers that correlate with the efficacy of DBS in patients with *** Preoperative imaging parameters were estimated and correlated with the 6-month clinical outcome of patients with TRD receiving combined bed nucleus of the stria terminalis(BNST)-nucleus accumbens(NAc)*** matter(WM)properties were extracted and compared between the response/non-response and remission/non-remission *** connectome was constructed and analysed using graph *** of the volume of activated tissue(VAT)to the main modulating tracts were also estimated to evaluate the *** Differences in fibre bundle properties of tracts,including superior thalamic radiation and reticulospinal tract,were observed between the remission and nonremission *** of the centre of the VAT to tracts connecting the ventral tegmental area and the anterior limb of internal capsule on the left side varied between the remission and non-remission groups(p=0.010,t=3.07).The normalised clustering coefficient(γ)and the small-world property(σ)in graph analysis correlated with the symptom improvement after the correction of *** Presurgical structural alterations in WM tracts connecting the frontal area with subcortical regions,as well as the distance of the VAT to the modulating tracts,may influence the clinical outcome of BNST-NAc *** findings provide potential imaging biomarkers for the DBS treatment for patients with TRD.

关键词： stimulation alterations treatment