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Discovery and development of synthetic tricyclic pyrroloquinone （TPQ） alkaloid analogs for human cancer therapy

Frontiers of Chemical Science and engineering 2016年第1期10卷 1-15页

作者： Wei Wang Bhavitavya Nijampatnam Sadanandan e. velu Ruiwen Zhang Department of Pharmaceutical Sciences School of Pharmacy Texas Tech University Health Sciences Center Amarillo TX 79106 USA Cancer Biology Center School of Pharmacy Texas Tech University Health Sciences Center Amarillo TX 79106 USA Department of Chemistry University of Alabama at Birmingham Birmingham AL 35294 USA

Natural products and their derivatives repre- sent a rich source for the discovery and development of new cancer therapeutic drugs. Bioactive components derived from natural sources including marine compounds have been shown to be effective agents in the clinic or in preclinical settings. In the present review, we present a story of discovery, synthesis and evaluation of three synthetic tricyclic pyrroloquinone （TPQ） alkaloid analogs as cancer therapeutic agents. Chemical synthesis of these compounds （BA-TPQ, TBA-TPQ, and TCBA-TPQ） has been accomplished and the mechanisms of action （MOA） and structure-activity relationships （SAR） have been investigated. In the past, the complexity of chemical synthesis and the lack of well-defined MOA have dampened the enthusiasm for the development of some makaluvamines. Recent discovery of novel molecular targets for these alkaloids （unrelated to inhibition of Topoisomerase II） warrant further consideration as clinical candidates in the future. In addition to the establishment of novel synthetic approaches and demonstration of in vitro and in vivo anticancer activities, we have successfully demonstrated that these makaluvamines attack several key molecular targets, including the MDM2-p53 pathway, providing ample opportunities of modulating the compound structure based on SAR and the use of such compounds in combination therapy in the future.

关键词： synthesis marine drugs tricyclic pyrroloqui- none alkaloid cancer therapy MDM2 p53

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Insulator Surface Charge Measurement Using an Improved Capacitive Probe

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Plasma Science and Technology 2006年第5期8卷 565-568页

作者：汪沨邱毓昌李欣然 PFeIFFeR W KUFFeL e State Key Lab for electrical Insulation and Apparatus Xi'an Jiaotong University Xi'an 710049 China School of Electrical and Information Engineering Hunan University Changsha 410082 China State Key Lab for electrical Insulation and Apparatus Xi'an Jiaotong University Xi'an 710049 China School of electrical and Information engineering Hunan University Changsha 410082 China Technische Universitat Darmstadt 64283 Darmstadt Germany Dept. of electrical engineering and Computer Science University of Manitoba Winnipeg Canada

A surface charge measuring system using the capacitive probe method is analysed. The present study shows that the measuring system cannot have a steady-state output and that the error resulting from the finite leakage resistance of the measuring system will be accumulated during the measuring process. Based on the theoretical analysis a new type probe with a low charge leakage and high resolution is designed. The surface charge accumulated on the Teflon insulator under a DC voltage is measured using this new probe and some phenomena of the surface charging are reported.

关键词： surface charge, insulator capacitive probe

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不同供钙水平下外源硅对辣椒生长及果实品质的影响

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北方园艺 2024年第18期 16-23页

作者：石玉王飞张帆王军娥张毅侯雷平山西农业大学园艺学院山西太谷030801

以辣椒品种“奥黛丽”为试材,采用基质盆栽的方式,设置4个不同供钙水平(1.5、1.0、0.5、0 mmol·L^(-1)Ca)和2个外源硅肥水平(1.5、0 mmol·L^(-1)Si),二者完全随机组合,共8个处理,研究了不同供Ca水平下施Si对辣椒生长及果实品质的影响... 详细信息

以辣椒品种“奥黛丽”为试材,采用基质盆栽的方式,设置4个不同供钙水平(1.5、1.0、0.5、0 mmol·L^(-1)Ca)和2个外源硅肥水平(1.5、0 mmol·L^(-1)Si),二者完全随机组合,共8个处理,研究了不同供Ca水平下施Si对辣椒生长及果实品质的影响,以期为设施辣椒优质高效肥料配施提供参考依据。结果表明:随供Ca水平的降低,辣椒幼苗的株高、茎粗与生物量积累逐渐下降,施加外源Si均不同程度促进了各水平下幼苗的生长;低Ca水平下,幼苗叶片的叶绿素含量、净光合速率、蒸腾速率、胞间CO_(2)浓度及气孔导度均不同程度下降,施Si显著缓解了低Ca水平对辣椒光合作用的抑制;随着供Ca水平的降低,辣椒的果实产量显著降低8.15%~73.23%(P<0.05),施Si则不同程度缓解了低Ca对辣椒产量的抑制;随供Ca水平的降低,辣椒果实的营养物质含量逐渐下降,施Si则显著改善了低Ca下辣椒的果实品质。因此,供Ca水平的降低会显著抑制辣椒生长发育及光合作用,降低果实的品质及产量,施加外源Si均可不同程度缓解低Ca胁迫对辣椒的伤害。

关键词：供钙水平外源硅辣椒生长果实品质

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Forge AHeAD with stricter criteria in future trials of embolic stroke of undetermined source

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Neural Regeneration Research 2022年第5期17卷 1009-1010页

作者： David Z.Rose Scott e.Kasner Department of Neurology Morsani College of MedicineUniversity of South FloridaTampaFLUSA Department of Neurology Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA

What lurks within the crypt?With more than 200 known causes of is chemic stroke(Saver,2016),what should be the minimum work up?Many centers offer high-resolution brain imaging and vessel studies,telemetry monitoring f... 详细信息

关键词： strict thoracic centers

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A CMOS wideband front-end chip using direct RF sampling mixer with embedded discrete-time filtering

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Journal of Semiconductors 2011年第8期32卷 111-117页

作者：许江涛 Carlos e.Saavedra 陈贵灿 Institute of Microelectronics Xi'an Jiaotong University Queen's University

A CMOS wideband front-end IC is demonstrated in this *** consists of a low noise transconductance amplifier（LNTA） and a direct RF sampling mixer（DSM） with embedded programmable discrete-time *** LNTA has the features of 0.5-6 GHz wideband,wideband input matching and low *** embedded filter following the DSM operates in discrete-time charge domain,filtering the aliasing signals and interferences while controlling the IF bandwidth according to the clock *** measured NF of the front-end was below 7 dB throughout the whole band from 0.5 to 6 *** shows a conversion gain of 12.6 dB and IP_（1dB） of-7.5 dBm at 2.4 *** occupies a chip area of 0.23 mm^2 and consumes 14 mA DC current.

关键词： wideband front-end LNTA DSM discrete time FIR filtering IIR windowed integration

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Optical bistability and multistability in a defect slab doped by GaAs/AlGaAs multiple quantum wells

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Chinese Physics B 2016年第5期25卷 223-228页

作者： Seyyed Hossein Asadpour G Solookinejad M Panahi e Ahmadi Sangachin Department of Physics Marvdasht Branch Islamic Azad University

We proposed a new model for controlling the optical bistability（OB） and optical multistability（OM） in a defect slab doped with four-level GaAs/AlGaAs multiple quantum wells with 15 periods of 17.5 nm GaAs wells and 15-nm Al_（0.3）Ga_（0.7）As barriers. The effects of biexciton energy renormalization, exciton spin relaxation, and thickness of the slab on the OB and OM properties of the defect slab were theoretically investigated. We found that the transition from OB to OM or vice versa is possible by adjusting the controllable parameters in a lab. Moreover, the transmission, reflection, and absorption properties of the weak probe light through the slab were also discussed in detail.

关键词： optical bistability optical multistability quantum well nanostructure

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Near shore waves,long-shore currents and sediment transport along micro-tidal beaches,central west coast of India

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International Journal of Sediment Research 2014年第3期29卷 402-413页

作者： Sajiv Philip CHeMPALAYIL v.Sanil KUMAR G.Udhaba DORA Glejin JOHNSON CSIR-National Institute of Oceanagraphy Dona PaulaGoaIndia

Coastlines are undergoing constant geomorphologic changes with respect to the incident wave *** on waves measured at 9 m water depth,simulation of near shore wave transformation is done using ReFDIF-1numerical model and the near shore breaker parameters are estimated at two micro-tidal beaches along central west coast of *** results are validated with measured *** the breaker parameters,long-shore current and long-shore sediment transport rates(LSTR) are computed by using semi-empirical *** long-shore current and LSTR are showing dramatic variations with respect to *** direction of LSTR is observed towards north since the approach waves are from south-west direction during pre-monsoon and post *** monsoon season,waves are from west south-west and resulted in southerly *** estimated annual net and gross LSTR by Cambridge environmental Research Consultants(CeRC) at two locations are in the same order whereas LSTR estimated by Walton & Bruno and Kamphuis equations are showing different estimations because of difference in surf-zone width and foreshore slope between the two *** micro-tidal beaches with length less than 6 km,Kamphuis equation is giving agreeable estimation of *** analysis of LSTR estimate shows that coastal inclination is the prominent factor in determining LSTR than incident wave angle.

关键词： Near-shore sedimentation Littoral zone Wave refraction Wave measurement Coastal zone management Karnataka coast

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Three-dimensional biomagnetic Maxwell fluid flow over a stretching surface in presence of heat source/sink

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International Journal of Biomathematics 2019年第3期12卷 207-226页

作者： M.G.Murtaza M.Ferdows J.C.Misra e.e.Tzirtzilakis Research Group of Fluid Flow Modeling and Simulation Department of Applied Mathematics University of Dhaka Dhaka-1000 Bangladesh Centre for Theoretical Studies Indian Institute of Technology Kharagpur Kharagpur 721302 India Fluid Dynamics & Turbomachinery Laboratory Department of Mechanical engineering Technological educational Institute of Western Greece 1 M. Aleksandrou Str Koukouli 26334 Patras Greece

The present paper deals with the study of three-dimensional boundary layer flow of biomagnetic Maxwell fluid over a plane horizontal surface stretched linearly along two mutually perpendicular directions. Basic principles of magnetohydrodynamics (MHD) and ferro-hydrodynamics (FHD) have been employed. The effect of heat generation/absorption has been taken into consideration. The study is theoretical and is conducted by using a combination of approximate and numerical techniques. By using the method of similarity transformation, the governing nonlinear partial differential equations are converted into a set of coupled ordinary differential equations. In the sequel, a suitable numerical method has been developed to solve the coupled differential equations. The accuracy of the numerical method has been checked by comparing the numerical results with those of an earlier study reported in available literatures. effects of various parameters involved in the study, viz. the magnetohydrodynamic and ferromagnetic parameters, Deborah number, stretching ratio and heat generation on the fluid flow profiles are investigated and the results have been presented graphically. variations of the skin friction, heat transfer rate and relative wall pressure with change in hydrodynamic and ferromagnetic parameters have also been illustrated. It is found that due to the influence of the Kelvin force, the velocity component in xx-direction is greater than the corresponding one in the hydrodynamic case, but the opposite is true for the velocity component in the yy-direction. We also found that the temperature of the fluid for hydrodynamic flow is greater than that for MHD or FHD flow. It is even greater for BFD flows. The numerical results of the study reveal that the characteristics of blood flow are significantly affected by the presence of a magnetic field.

关键词： Biomagnetic fluid magnetic dipole magnetization heat transfer stretching surface

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effects of fibers on expansive shotcrete mixtures consisting of calcium sulfoaluminate cement,ordinary Portland cement,and calcium sulfate

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Journal of Rock Mechanics and Geotechnical engineering 2018年第2期10卷 212-221页

作者： H.Yu L.Wu W.v.Liu Y.Pourrahimian School of Mining and Petroleum engineering Department of Civil and Environmental Engineering University of Alberta

The mining industry often uses shotcrete for ground stabilization. However, cracking within shotcrete is commonly observed, which delays production schedules and increases maintenance costs. A possible crack reduction method is using expansive shotcrete mixture consisting of calcium sulfoaluminate cement(CSA), ordinary Portland cement(OPC), and calcium sulfate(CS) to reduce shrinkage. Furthermore, fibers can be added to the mixture to restrain expansion and impede cracking. The objective of this paper is to study the effects of nylon fiber, glass fiber, and steel fiber on an expansive shotcrete mixture that can better resist cracking. In this study, parameters such as density, water absorption, volume of permeable voids, unconfined compressive strength(UCS), splitting tensile strength(STS), and volume change of fiber-added expansive mixtures were determined at different time periods(i.e. the strengths on the 28 th day, and the volume changes on the 1 st, 7 th, 14 th, 21 st, and 28 th days). The results show that addition of fibers can improve mixture durability, in the form of decreased water absorption and reduced permeable pore space content. Moreover, the expansion of the CSA-OPC-CS mixture was restrained up to50% by glass fiber, up to 43% by nylon fiber, and up to 28% by steel fiber. The results show that the STS was improved by 57% with glass fiber addition, 43% with steel fiber addition, and 38% with nylon fiber addition. The UCS was also increased by 31% after steel fiber addition, 26% after nylon fiber addition, and16% after glass fiber addition. These results suggest that fiber additions to the expansive shotcrete mixtures can improve durability and strengths while controlling expansion.

关键词： Shotcrete Restrained expansion Fibers Calcium sulfoaluminate cement(CSA) Ordinary Portland cement(OPC) Calcium sulfate(CS)

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Cell proliferation and apoptosis in optic nerve and brain integration centers of adult trout Oncorhynchus mykiss after optic nerve injury

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Neural Regeneration Research 2016年第4期11卷 578-590页

作者： evgeniya v.Pushchina Sachin Shukla Anatoly A.varaksin Dmitry K.Obukhov Laboratory of Cytophysiology A.V.Zhirmunsky Institute of Marine Biology Far Eastern Branch of Russian Academy of Sciences Prof.Brien Holden eye Research Centre L.V.Prasad Eye Institute St.Petersburg State University Universitetskaya

Fishes have remarkable ability to effectively rebuild the structure of nerve cells and nerve fibers after central nervous system ***,the underlying mechanism is poorly *** order to address this issue,we investigated the proliferation and apoptosis of cells in contralateral and ipsilateral optic nerves,after stab wound injury to the eye of an adult trout Oncorhynchus *** population of proliferating cells was investigated at 1 week after *** labeling gave a qualitative and quantitative assessment of apoptosis in the cells of optic nerve of trout 2 days after *** optic nerve injury,apoptotic response was investigated,and mass patterns of cell migration were *** maximal concentration of apoptotic bodies was detected in the areas of mass clumps of *** is probably indicative of massive cell death in the area of high phagocytic activity of macrophages/*** 1 week after optic nerve injury,we observed nerve cell proliferation in the trout brain integration centers：the cerebellum and the optic *** the optic tectum,proliferating cell nuclear antigen（PCNA）-immunopositive radial glia-like cells were *** activity of nerve cells was detected in the dorsal proliferative（matrix） area of the cerebellum and in parenchymal cells of the molecular and granular layers whereas local clusters of undifferentiated cells which formed neurogenic niches were observed in both the optic tectum and cerebellum after optic nerve *** vitro analysis of brain cells of trout showed that suspension cells compared with monolayer cells retain higher proliferative activity,as evidenced by PCNA *** contrast observation showed mitosis in individual cells and the formation of neurospheres which gradually increased during 1–4 days of *** present findings suggest that trout can be used as a novel model for studying neuronal regeneration.

关键词： nerve regeneration proliferation apoptosis optic nerve brain radial glia cells neurogenic niches neurospheres neural regeneration

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