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Gnetifolin K, a New Stilbene Diglucoside from Gnetum parvifolium

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Chinese Chemical Letters 1997年第6期8卷 509-510页

作者： Xu, Q lin, m CHINESE ACAD mED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA BEIJING UNION mED COLL BEIJING 100050PEOPLES R CHINA

A new stilbene diglucoside, gnetifolin K, was isolated from the lianas of Gnetum parvifolium. Its structure was established as isorhapotigenin-3,4'-di-O-beta-D-glucoside on the basis of spectral and chemical evidence.

关键词： Gnetifolin K a New Stilbene Diglucoside from Gnetum parvifolium

DNS in evolution of vorticity and sign relationship in wake transition of a circular cylinder:(pure)mode A

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Acta mechanica Sinica 2019年第6期35卷 1131-1149页

作者： L.m.lin Z.R.Tan Key Laboratory for mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Navigation Wuhan University of TechnologyWuhan 430063China Hubei Key Laboratory of Inland Shipping Technology Wuhan University of TechnologyWuhan 430063China

In the present paper,the spatio-temporal evolution of vorticity in the first wake instability,i.e.,(pure)mode A,is investigated in order to understand the wake vortex dynamics and sign relationships among vorticity *** numerical simulation(DNS)for the flow past a circular cylinder is performed,typically at a Reynolds number of 200,in the three-dimensional(3-D)wake *** to characteristics of time histories of fluid forces,three different stages are identified as the computational transition,the initial stage and fully developed *** the second initial stage,the original two-dimensional spanwise vortices become obviously three-dimensional associated with the streamwise or vertical vorticity intensified up to about *** a matter of fact,these additional vorticities,caused by the intrinsic 3-D instability,are already generated firstly on cylinder surfaces early in the computational transition,indicating that the three-dimensionality appeared early near the *** evolution of additional components of vorticity with features the same as mode A shows that(pure)mode A can be already formed in the late computational *** careful analysis of the vorticity field on the front surface,in the shear layers and near wake at typical times,two sign laws are *** illustrate intrinsic relationships among three vorticity components,irrelevant to the wavelength or Fourier mode and Reynolds number in(pure)mode *** importantly,the origin of streamwise vortices is found and explained by a new physical mechanism based on the theory of vortex-induced *** a result,the whole process of formation and shedding vortices with these vorticities is firstly and completely *** characteristics are presented in detail.

关键词： Wake transition Circular cylinder Vorticity mode A Sign law

A note on the numerical simulations of flow past a wavy square-section cylinder

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Acta mechanica Sinica 2008年第1期24卷 101-105页

作者： G. C. ling L. m. lin The State Key Laboratory of Nonlinear mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The flow past a square-section cylinder with a geometric disturbance is investigated by numerical simulations. The extra terms, due to the introduction of mapping transformation simulating the effect of disturbance into the transformed Navier-Stokes equations, are correctly derived, and the incorrect ones in the previous literature are pointed out and analyzed. Furthermore, the relationship between the vorticity, especially on the cylinder surface, and the disturbance is derived and explained theoretically. The computations are performed at two Reynolds numbers of 100 and 180 and three amplitudes of waviness of 0.006, 0.025 and 0.167 with another aim to explore the effects of different Reynolds numbers and disturbance on the vortex dynamics in the wake and forces on the body. Numerical results have shown that, at the mild waviness of 0.025, the Kairmain vortex shedding is suppressed completely for Re = 100, while the forced vortex dislocation is appeared in the near wake at the Reynolds number of 180. The drag reduction is up to 21.6% at Re = 100 and 25.7% at Re = 180 for the high waviness of 0.167 compared with the non-wavy cylinder. The lift and the Strouhal number varied with different Reynolds numbers and the wave steepness are also obtained.

关键词： Numerical simulation. Geometric disturbance.Square-section cylinder Wake flow

Effect of perforation on flow past a conic cylinder at Re=100:vortex-shedding pattern and force history

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Acta mechanica Sinica 2018年第2期34卷 238-256页

作者： L.m.lin X.F.Zhong Y.X.Wu Key Laboratory for mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences

The flow past a circular-section cylinder with a conic shroud perforated with four holes at the peak was simulated numerically at Re = 100, considering two factors, *** angle of attack and the diameter of the holes. The effects of the perforated conic shroud on the vortex shedding pattern in the near wake was mainly investigated, as well as the time history of the drag and lift forces. In the investigated parameter space, three flow regimes were generally identified, corresponding to weak, moderate, and strong disturbance *** regime I, the wake can mainly be described by alternately shedding Kármán or Kármán-like vortices. In regime II, the spanwise vortices are obviously disturbed along the span due to the appearance of additional vorticity components and their interactions with the spanwise vortices, but still shed in synchronization along the spanwise direction. In regime III,the typical Kármán vortices partially or totally disappear,and some new vortex shedding patterns appear, such as-type, obliquely shedding, and crossed spanwise vortices with opposite sign. Corresponding to these complex vortex shedding patterns in the near wake, the fluid forces no longer oscillate regularly at a single vortex shedding frequency, but rather with a lower modulation frequency and multiple amplitudes. An overview of these flow regimes is presented.

关键词： Vortex shedding pattern Fluid forces Flow control Conical shroud Perforation

Effect of perforation on flow past a conic cylinder at Re =100: wavy vortex and sign laws

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Acta mechanica Sinica 2018年第5期34卷 812-829页

作者： L.m.lin X.F.Zhong Y.X.Wu Key Laboratory for mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

In order to find the intrinsic physical mechanism of the original Kármán vortex wavily distorted across the span due to the introduction of three-dimensional (3-D) geometric disturbances,a flow past a peak-perforated conic shroud is numerically simulated at a Reynolds number of *** on previous work by meiburg and Lasheras (1988),the streamwise and vertical interactions with spanwise vortices are introduced and *** vortex-shedding patterns in the near wake for different flow regimes are reinspected and illustrated from the view of these two ***,in regime Ⅰ,spanwise vortices are a little distorted due to the weak *** in regime Ⅱ,spanwise vortices,even though curved obviously,are still shed synchronously with moderate streamwise and vertical *** in regime Ⅲ,violently wavy spanwise vortices in some vortex-shedding patterns,typically an Ω-type vortex,are mainly attributed to the strong vertical interactions,while other cases,such as multiple vortex-shedding patterns in sub-regime Ⅲ-D,are resulted from complex streamwise and vertical interactions.A special phenomenon,spacial distribution of streamwise and vertical components of vorticity with specific signs in the near wake,is analyzed based on two models of streamwise and vertical vortices in explaining physical reasons of top and bottom shear layers wavily varied across the *** these two models and above two interactions are *** two sign laws are summarized:the first sign law for streamwise and vertical components of vorticity is positive in the upper shear layer,but negative in the lower shear layer,while the second sign law for three vorticity components is always negative in the wake.

关键词： Vortex-shedding pattern Flow control Vortex dynamics Conic disturbance Perforation Sign law

New interpretation of specific sign of Reynolds stress in the boundary layer on a flat plate

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Theoretical & Applied mechanics Letters 2018年第6期8卷 372-377,I0003页

作者： L.m.lin Y.X.Wu Key Laboratory for mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences School of Engineering Sciences University of Chinese Academy of Sciences

The specific sign of Reynolds stress in the boundary layer on a flat plate at zero incidence is newly interpreted in present paper based on the theory of vortex-induced vortex. It avoids some problems appeared in a traditional explanation, on the basis of relationship between mean and fluctuating flows due to the transport of momentum. Through the analysis of local flow field in the immediate neighborhood of wall, the characteristics of Reynolds stress are identified through introducing turbulence-induced small-scale streamwise eddies above the flat plate. The positive Reynolds stress is theoretically verified. And such new interpretation illustrates that the generation of Reynolds stress, as well as fluctuating velocity, is intrinsically independent of the mean flow. But its specific sign would be determined by the mean flow due to the inertial forces. Other features,such as the intensity relationship among three components of fluctuating velocity, are also presented.

关键词： Reynolds shear stress Sign Boundary layer Flatplate Turbulence

Advances in immuno-oncology biomarkers for gastroesophageal cancer:programmed death ligand 1,microsatellite instability,and beyond

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World Journal of Gastroenterology 2018年第25期24卷 2686-2697页

作者： Emily m lin Jun Gong Samuel J Klempner Joseph Chao Department of Internal medicine Harbor-UCLA Medical CenterTorranceCA 90509United States Department of medical Oncology and Developmental Therapeutics City of Hope Comprehensive Cancer CenterDuarteCA 91010United States The Angeles Clinic and Research Institute Los AngelesCA 90404United States Samuel Oschin Comprehensive Cancer Institute Cedars-Sinai Medical CenterLos AngelesCA 90048United States

Blockade of the programmed death ligand 1(PD-L1) and programmed cell death 1(PD-1) receptor axis represents an effective form of cancer immunotherapy. Preclinical evidence initially suggested that gastric and gastroesophageal junction(GEJ) cancers are potentially immunotherapy-sensitive tumors. Early phase clinical trials have demonstrated promising antitumor activity with PD-1/PD-L1 blockade in advanced or metastatic gastric/GEJ cancer. microsatellite instability(mSI) and PD-L1 expression have been shown to predict higher response to PD-1 inhibitors as highlighted by the recent approvals of pembrolizumab in treatmentrefractory solid tumors with mSI status and the thirdline or greater treatment of PD-L1 positive advanced gastric/GEJ cancers. However, predictive and prognostic biomarkers remain an ongoing need. In this review, we detail the preclinical evidence and early tissue biomarker analyses illustrating potential predictive biomarkers to PD-1/PD-L1 blockade in gastric/GEJ cancer. We also review the clinical development of PD-1/PD-L1 inhibitors in gastric/GEJ cancer and highlight several areas in need of future investigation in order to optimize the efficacy of PD-1/PD-L1 blockade in gastric/GEJ cancer.

关键词： Immunotherapy programmed cell death 1 programmed death ligand 1 microsatellite instablility Gastric cancer

The role of N-glycosylation in cancer

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1098-1110页

作者： Yu lin David m.Lubman Department of Surgery University of Michigan Medical CenterAnn ArborMI 48109USA

Despite advances in understanding the development and progression of cancer in recent years,there remains a lack of comprehensive characterization of the cancer *** play an important role in medicine and are involved in various human disease conditions including ***-moieties participate in fundamental cancer processes like cell signaling,invasion,angiogenesis,and *** N-glycosylation significantly impacts cancer processes and targeted therapies in ***,understanding N-glycosylation in a tumor is essential for comprehending disease progression and discovering anti-cancer targets and biomarkers for therapy monitoring and *** review presents the fundamental process of protein N-glycosylation and summarizes glycosylation changes in tumor cells,including increased terminal sialylation,N-glycan branching,and ***,the role of N-glycosylation in tumor signaling pathways,migration,and metabolism are *** and glycopeptides as potential biomarkers for early detection of cancer based on site specificity have been ***,understanding and exploring the cancer glycoproteome,along with its role in medicine,implication in cancer and other human diseases,highlights the significance of N-glycosylation in tumor processes,necessitating further research for potential anticancer targets and biomarkers.

关键词： N-Glycosylated proteins Cancer signaling Cancer angiogenesis Cancer metabolism Cancer biomarkers

High electromechanical reponses of ultra-high-density aligned nano-porous microwave exfoliated graphite oxide/polymer nanocomposites ionic actuators

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International Journal of Smart and Nano materials 2014年第2期5卷 114-122页

作者： m.Ghaffari Y.Zhou m.lin Chong min Koo Q.m.Zhang Department of materials Science and Engineering Materials Research InstituteThe Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Electrical Engineering Materials Research InstituteThe Pennsylvania State UniversityUniversity ParkPA 16802USA materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA Center for materials Architecturing Institute for Multi-Disciplinary Convergence of MaterialsKorea Institute of Science and Technology(KIST)Hwarangno 14-gil 5Soengbuk-guSeoul 136-791Republic of Korea

High elastic energy density and high-efficiency ionic electromechanical actuators were prepared from aligned activated microwave exfoliated graphite oxide(A-amEGO)/polymer nano-composites,and the electromechanical performance was *** elastic modulus and elastic energy density of the ionic actuators can be tuned over a wide range by varying the polymer(poly(vinylidene fluoride/chlorotrifluoroethylene)[P(VDF-CTFE)])concentration in the nano-composite *** A-amEGO/P(VDF-CTFE)nano-composite actuators with 35 wt.%of polymer content exhibit an elastic energy density higher than 5 J/cm^(3) and an electromechanical conversion efficiency higher than 3.5%,induced under 4 *** results show the promise of high-density highly aligned graphene electrodes for high-performance ionic electromechanical transduction devices.

关键词： nano-porous activated microwave exfoliated graphite oxide(amEGO) actuator self-assembly elastic modulus elastic energy density