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Management of isolated superior mesenteric artery dissection

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World Journal of Gastroenterology 2014年第45期20卷 17179-17184页

作者： Peng-Hua Lv Xi-Cheng Zhang Li-Fu Wang Zhao-Lei Chen hai-bin shi Department of Interventional Radiology Northern Jiangsu People’s Hospital Department of Radiology First Hospital Affiliated to Nanjing Medical University Department of Vascular Surgery Northern Jiangsu People’s Hospital

AIM: To evaluate our experience of the clinical management of spontaneous isolated superior mesenteric artery dissection (ISMAD).

关键词： Intestine Superior mesenteric artery Dissection Therapy Endovascular reconstruction

Learning topological defects formation with neural networks in a quantum phase transition

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Communications in Theoretical Physics 2024年第5期76卷 68-76页

作者： Han-Qing shi hai-Qing Zhang Center for Gravitational Physics Department of Space ScienceBeihang UniversityBeijing 100191China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

Neural networks possess formidable representational power,rendering them invaluable in solving complex quantum many-body *** they excel at analyzing static solutions,nonequilibrium processes,including critical dynamics during a quantum phase transition,pose a greater challenge for neural *** address this,we utilize neural networks and machine learning algorithms to investigate time evolutions,universal statistics,and correlations of topological defects in a one-dimensional transverse-field quantum Ising ***,our analysis involves computing the energy of the system during a quantum phase transition following a linear quench of the transverse magnetic field *** excitation energies satisfy a power-law relation to the quench rate,indicating a proportional relationship between the excitation energy and the kink ***,we establish a universal power-law relationship between the first three cumulants of the kink numbers and the quench rate,indicating a binomial distribution of the ***,the normalized kink-kink correlations are also investigated and it is found that the numerical values are consistent with the analytic formula.

关键词： neural networks machine learning transverse-field quantum Ising model kibble-zurek mechanism

Redox-Active Dihydrophenazine-Based Macrocycle:Synthesis,Conformation-Adaptive Behavior and Host-Guest Complexation with Tetracyanoquinodimethane

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Chinese Journal of Chemistry 2024年第16期42卷 1895-1900页

作者： Qiong-Yan Hong bin Huang Meng-Xiang Wu Lin Xu Xiao-Li Zhao Xueliang shi hai-Bo Yang Shanghai Key Laboratory of Green Chemistry and Chemical Processes State Key Laboratory of Petroleum Molecular&Process EngineeringSchool of Chemistry and Molecular EngineeringEast China Normal University3663 N.Zhongshan RoadShanghai 200062China

A novel macrocycle based on conformation-adaptive and electron-rich dihydrophenazine was designed and *** the one hand,the macrocycle showed host-guest interactions with tetracyanoquinodimethane(TCNQ)driving by charge transfer interaction between ***,host-guest complexation was accompanied by fluorescence quenching and conformational change of the *** the other hand,the oxidation of the macrocycle resulted in its diradical cation analogue and induced the release of the guest molecule TCNQ,thereby accomplishing reversible binding ***,this work wellillustrates the chemical and structural versatility of dihydrophenazine in the synthesis of macrocycles and their host-guest chemistry.

关键词： Dihydrophenazine Macrocycle Conformational adaptation Redox-active Host-guest interactions Charge transfer interaction Organic radical Supramolecular chemistry

A Rendezvous Mission to the Second Earth Trojan Asteroid 2020 XL_5 with Low-Thrust Multi-Gravity Assist Techniques

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Research in Astronomy and Astrophysics 2024年第1期24卷 245-264页

作者： shi-hai Yang Bo Xu Xin Li School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China

As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5) is ***, due to its high inclination and large eccentricity, direct impulsive transfer requires large amounts of fuel consumption. To address this challenge, we explore the benefits of electric propulsion and multi-gravity assist techniques for interplanetary missions. These two techniques are integrated in this mission design. The design of a low-thrust gravity-assist(LTGA) trajectory in multi-body dynamics is thoroughly investigated,which is a complex process. A comprehensive framework including three steps is presented here for optimization of LTGA trajectories in multi-body dynamics. The rendezvous mission to 2020 XL_(5) is designed with this three-step approach. The most effective transfer sequence among the outcomes involves Earth–Venus–Earth–Venus-2020 XL_(5). Numerical results indicate that the combination of electric propulsion and multi-gravity assists can greatly reduce the fuel consumption, with fuel consumption of 9.03%, making it a highly favorable choice for this rendezvous mission.

关键词： minor planets asteroids:general celestial mechanics Planetary Systems

Value of multiple models of diffusion-weighted imaging to predict hepatic lymph node metastases in colorectal liver metastases patients

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World Journal of Gastroenterology 2024年第4期30卷 308-317页

作者： hai-bin Zhu Bo Zhao Xiao-Ting Li Xiao-Yan Zhang Qian Yao Ying-shi Sun Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of RadiologyPeking University Cancer Hospital and InstituteBeijing 100142China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of PathologyPeking University Cancer Hospital and InstituteBeijing 100142China

BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindication for liver *** to now,there’s still lack of reliable preoperative methods to assess the status of hepatic lymph nodes in patients with CRLM,except for pathology examination of lymph node after *** To compare the ability of mono-exponential,bi-exponential,and stretchedexponential diffusion-weighted imaging(DWI)models in distinguishing between benign and malignant hepatic lymph nodes in patients with CRLM who received neoadjuvant chemotherapy prior to *** In this retrospective study,97 CRLM patients with pathologically confirmed hepatic lymph node status underwent magnetic resonance imaging,including DWI with ten b values before and after *** parameters,such as the apparent diffusion coefficient from the mono-exponential model,and the true diffusion coefficient,the pseudo-diffusion coefficient,and the perfusion fraction derived from the intravoxel incoherent motion model,along with distributed diffusion coefficient(DDC)andαfrom the stretched-exponential model(SEM),were *** parameters before and after chemotherapy were compared between positive and negative hepatic lymph node groups.A nomogram was constructed to predict the hepatic lymph node *** reliability and agreement of the measurements were assessed using the coefficient of variation and intraclass correlation *** Multivariate analysis revealed that the pre-treatment DDC value and the short diameter of the largest lymph node after treatment were independent predictors of metastatic hepatic lymph nodes.A nomogram combining these two factors demonstrated excellent performance in distinguishing between benign and malignant lymph nodes in CRLM patients,with an area under the curve of ***,parameters from SEM sho

关键词： Colorectal cancer Individualized treatment Diffusion magnetic resonance imaging Intravoxel incoherent motion Liver

Surface states modulated exchange interaction in Bi2Se3/thulium iron garnet heterostructures

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Chinese Physics B 2020年第11期29卷 151-155页

作者： hai-bin shi Li-Qin Yan Yang-Tao Su Li Wang Xin-Yu Cao Lin-Zhu Bi Yang Meng Yang Sun Hong-Wu Zhao Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

We investigate the modulation of magnetic anisotropy of thulium iron garnet(TmIG)films by interfaced Bi2Se3 thin *** quality epitaxial growth of Bi2Se3 films has been achieved by molecular beam epitaxy on TmIG *** the method of ferromagnetic resonance,we find that the perpendicular magnetic anisotropy(PMA)of TmIG can be greatly strengthened by the adjacent Bi2Se3 ***,the competition between topological surface states and thickness dependent bulk states of Bi2Se3 gives rise to the modulation of PMA of the Bi2Se3/TmIG *** interfacial interaction can be attributed to the enhanced exchange coupling between Fe^3+ions of TmIG mediated by topological surface electrons of Bi2Se3.

关键词： topological surface states interfacial exchange coupling perpendicular magnetic anisotropy

Combustion mechanism of benzene in iron ore sintering process:experimental and simulation

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Journal of Iron and Steel Research International 2024年第1期31卷 195-203页

作者： Zhi-gang Que Jin-ming shi Xian-bin Ai Institute of Energy Research Jiangxi Academy of ScienceNanchang330096JiangxiChina Jiangxi Carbon Neutralization Research Center Nanchang330096JiangxiChina

Benzene is a typical component of volatile organic compounds(VOCs)in the iron ore sintering flue *** combustion behavior of benzene directly affects the emission of VOCs in iron ore sintering *** effects of temperature,benzene,and oxygen concentrations on the conversion ratio of benzene were investigated by experiments and numerical *** experiments were carried out in a tube reactor at temperatures of 773-1098 K,benzene concentrations of 0.01-0.03 vol.%,and oxygen concentrations of 10-21 vol.%.The numerical simulation was performed with the plug flow model in the CHEMKIN program based on a kinetic model that consists of 132 chemical species and 772 elementary step-like *** experimental results reveal that increasing the temperature and benzene concentration could signifi-cantly promote benzene *** is attributed to the increase in the reaction rates of all steps in the pathway for forming CO_(2)and H_(2)*** addition,due to the large equivalent ratio of oxygen to benzene,the conversion ratio of benzene remained constant at different oxygen *** simulation results were in good agreement with the experimental results and indicated that six elementary reactions dominated the formations of CO_(2)and H_(2)*** oxidations of C_(6)H_(5)O,CO,and C_(5)H_(4)O intermediates to CO_(2)were the limiting steps in the reaction pathways.

关键词： Benzene Volatile organic compound Iron ore sinter Combustion Simulation Temperature Oxygen

Performance and enhanced oil recovery efficiency of an acid-resistant polymer microspheres of anti-CO2 channeling in low-permeability reservoirs

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Petroleum Science 2024年第4期21卷 2420-2432页

作者： hai-Zhuang Jiang Hong-bin Yang Ruo-Sheng Pan Zhen-Yu Ren Wan-Li Kang Jun-Yi Zhang shi-Long Pan Bauyrzhan Sarsenbekuly State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Oil and Gas Engineering Research Institute School of Energy and Petroleum Industry Kazakh-British Technical University

CO2flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can also cause severe CO2gas channeling ***,anti-gas channeling is a necessary measure to improve the effect of *** kind of anti-gas channeling refers to the plugging of fractures in the deep formation to prevent CO2gas channeling,which is different from the wellbore *** microspheres have the characteristics of controllable deep plugging,which can achieve the profile control of low-permeability fractured *** acidic environments with supercritical CO2,traditional polymer microspheres have poor expandability and plugging *** on previous work,a systematic evaluation of the expansion performance,dispersion rheological properties,stability,deep migration,anti-CO2channeling and enhanced oil recovery ability of a novel acid-resistant polymer microsphere（DCNPM-A） was carried out under CQ oilifield conditions（salinity of85,000 mg/L,80℃,pH=3）.The results show that the DCNPM-A microsphere had a better expansion performance than the traditional microsphere,with a swelling rate of *** microsphere dispersion with a concentration of 0.1%-0.5% had the advantages of low viscosity,high dispersion and good injectability in the low permeability fractured *** the acidic environment of supercritical CO2,DCNPM-A microspheres showed excellent stability and could maintain strength for over 60 d with less *** core experiments,DCNPM-A microspheres exhibited delayed swelling characteristics and could effectively plug deep *** a plugging rate of 95%,the subsequent enhanced oil recovery of CO2flooding could reach 21.03%.The experimental results can provide a theoretical basis for anti-CO2channeling and enhanced oil recovery in low-permeability fractured reservoirs.

关键词： Low-permeability reservoir Anti-CO 2 channeling Polymer microsphere Acid resistance

Privacy-Preserving Frank-Wolfe on Shuffle Model

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 887-907页

作者： Ling-jie ZHANG shi-song WU hai ZHANG School of Mathematics Northwest UniversityXi’an 710127China School of Mathematics and Information Science Baoji University of Arts and SciencesBaoji 721013China China Southern Power Grid Artificial Intelligence Technology Company Limited Guangzhou 510700China

In this paper,we design the differentially private variants of the classical Frank-Wolfe algorithm with shuffle model in the optimization of machine *** weak assumptions and the generalized linear loss(GLL)structure,we propose a noisy Frank-Wolfe with shuffle model algorithm(NoisyFWS)and a noisy variance-reduced Frank-Wolfe with the shuffle model algorithm(NoisyVRFWS)by adding calibrated laplace noise under shuffling scheme in thel_(p)(p∈[1,2])-case,and study their privacy as well as utility guarantees for the H?lder smoothness *** particular,the privacy guarantees are mainly achieved by using advanced composition and privacy amplification by *** utility bounds of the Noisy FWS and NoisyVRFWS are analyzed and obtained the optimal excess population risksO(n-(1+α/4α+log(d)√log(1/δ)/n∈and O(n-1+α/4α+log(d)√log1(+δ)/n^(2)∈with gradient complexity O(n(1+α)^(2)/4α^(2)forα∈[1/√3,1].It turns out that the risk rates under shuffling scheme are a nearly-dimension independent rate,which is consistent with the previous work in some *** addition,there is a vital tradeoff between(α,L)-Holder smoothness GLL and the gradient *** linear gradient complexity O(n)is showed by the parameterα=1.

关键词： differential privacy Frank-Wolfe algorithm privacy amplification shuffle model