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100-gb/s undersea transmission with high spectral efficiency using pre-filtered QPSK modulation format

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Chinese Optics Letters 2010年第9期8卷 831-836页

作者： J.-X. Cai Y. Cai C. R. Davidson D. g. Foursa A. Lucero O. Sinkin W. Patterson A. Pilipetskii g. Mohs Neal S. Bergano Tyco Electronics Subsea Communications LLC ("TE SubCom" formerly known as ~co Telecommunications (US) Inc.) 250 Industrial Way West Eatontown NJ 07724 USA

We provide a review of our recent 100-gb/s, high spectral efficiency （SE） experiment targeting transoceanic and regional undersea transmission distances. We demonstrated that simple pre-filtering at the transmitter together with a maximum a posteriori probability （MAP） detection algorithm can significantly improve SE. We transmitted 96×100-gb/s pre-filtered polarization division multiplexed return-to-zero quadrature phase shift keyed （PDM-RZ-QPSK） channels with 300% SE over 10608 km using 52-km spans of 150-μm 2 fiber and simple single-stage erbium-doped fiber amplifiers （EDFAs）. We also achieved 400% SE over 4368 km using similar techniques.

关键词： Bit error rate Erbium doped fiber amplifiers Modulation Optical signals Quadrature phase shift keying Signal processing

Highly electroactive N–Fe hydrothermal carbons and carbon nanotubes for the oxygen reduction reaction

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Journal of Energy Chemistry 2020年第11期29卷 260-270页

作者： R.g.Morais N.Rey-Raap J.L.Figueiredo M.F.R.Pereira Associate Laboratory LSRE-LCM Departamento de Engenharia QuimicaFaculdade de EngenhariaUniversidade do PortoR.Dr.Roberto Frias s/n4200-465PortoPortugal

glucose-derived carbons were prepared by hydrothermal carbonization of glucose followed by carbonization or activation to obtain carbon materials with different microporosities. These microporous carbons and carbon nanotubes(CNTs) were functionalized with melamine and/or iron(Ⅱ) phthalocyanine(FePc)following three different methodologies:(i) Functionalization with melamine via thermal treatment,(ii)incorporation of the lowest amount of FePc reported in the literature via incipient wetness impregnation followed by thermal treatment and(iii) functionalization with melamine followed by Fe Pc *** chemical and textural characterization of the prepared materials and their electrochemical assessment allowed to understand the role of microporosity in the incorporation of FePc and its effect on the oxygen reduction reaction(ORR). It was observed that FePc was preferentially incorporated inside the porous structure, especially in samples with more developed microporosity. However, functionalization with melamine modified the textural properties and the surface chemistry, favoring the incorporation of FePc on the surface. Regarding the electrochemical performance, the presence of FePc greatly enhanced the electroactivity of the microporous catalysts. An onset potential of 0.88 V and a four-electron pathway were obtained for glucose-derived carbons, whereas the limiting current densities and kinetic current densities rose by 126% and 222%, respectively, in comparison to the base sample. Notwithstanding, the highest electrochemical activity was observed for the sample prepared with CNTs, due to the synergy between the active metal centers and their highly graphitic carbon structure. The electrochemical parameters of CNTFeP csurpass the commercial Pt/C. The half-wave potential is 40 mV higher, the limiting current density increases by 17%, and a negligible production of by-products(< 1%) was observed.

关键词： Iron(Ⅱ)phthalocyanine Hydrothermal carbons Carbon nanotubes Oxygen reduction reaction Electrocatalysis

Reducing force transmissibility in multiple degrees of freedom structures through anti-symmetric nonlinear viscous damping

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Acta Mechanica Sinica 2012年第5期28卷 1436-1448页

作者： Z.-K.Peng Z.-Q.Lang g.Meng S.A.Billings State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Department of Automatic Control and Systems Engineering University of Sheffield

In the present study, the Volterra series theory is adopted to theoretically investigate the force transmissibility of multiple degrees of freedom （MDOF） structures, in which an isolator with nonlinear anti-symmetric viscous damping is assembled. The results reveal that the anti-symmetric nonlinear viscous damping can significantly reduce the force trans- missibility over all resonance regions for MDOF structures with little effect on the transmissibility over non-resonant and isolation regions. The results indicate that the vibration isolators with an anti-symmetric damping characteristic have great potential to solve the dilemma occurring in the design of linear viscously damped vibration isolators where an increase of the damping level reduces the force transmissibility over resonant frequencies but increases the transmissibility over non-resonant frequency regions. This work is an extension of a previous study in which MDOF structures installed on the mount through an isolator with cubic nonlinear damping are considered. The theoretical analysis results are also verified by simulation studies.

关键词： Nonlinear viscous damping Force transmissibility - Vibration isolation Volterra series

Melatonin prevents oxidative stress,inflammatory activity,and DNA damage in cirrhotic rats

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World Journal of gastroenterology 2022年第3期28卷 348-364页

作者： Josieli R Colares Renata M Hartmann Elizângela g Schemitt Sandielly R B Fonseca Marilda S Brasil Jaqueline N Picada Alexandre S Dias Aline F Bueno Cláudio A Marroni Norma P Marroni Medical Sciences Program Universidade Federal do Rio Grande do SulPorto Alegre 90050-170Brazil Marilda S BrasilNorma Biological Sciences Program Universidade Federal do Rio Grande do SulPorto Alegre 90050-170Brazil Cellular and Molecular Biology Program Lutheran University of Brazil(ULBRA)Canoas 92425-900Brazil Pneumological Sciences Program Universidade Federal do Rio Grande do SulPorto Alegre 90050-170Brazil Posgraduate Program in Hepatology Universidade Federal de Ciências da Saúde de Porto AlegrePorto Alegre 90050-170Brazil

BACKgROUND Cirrhosis is an important health problem characterized by a significant change in liver *** animals,this can be reproduced by an experimental model of bile duct ligation(BDL).Melatonin(MLT)is a physiological hormone synthesized from serotonin that has been studied for its beneficial properties,including its antioxidant *** To evaluate MLT’s effects on oxidative stress,the inflammatory process,and DNA damage in an experimental model of secondary biliary *** Male Wistar rats were divided into 4 groups:Control(CO),CO+MLT,BDL,and BDL+*** was administered(20 mg/kg)daily beginning on day 15 after biliary *** day 29 the animals were *** samples,liver tissue,and bone marrow were collected for further *** BDL caused changes in biochemical and histological parameters and markers of inflammatory *** acid(0.46±0.01)reactive substance levels,superoxide dismutase activity(2.30±0.07)and nitric oxide levels(2.48±0.36)were significantly lower(Pgroups that received *** damage was also lower(Pgroups(171.6±32.9)than the BDL-only group(295.5±34.8).Tissue damage and the expression of nuclear factor kappa B,interleukin-1β,Nrf2,NQO1 and Hsp70 were significantly lower in animals treated with MLT(P<0.001).CONCLUSION When administered to rats with BDL-induced secondary biliary cirrhosis,MLT effectively restored the evaluated parameters.

关键词： Antioxidants Secondary biliary cirrhosis Oxidative stress Melatonin Bile duct ligation

The Superconductivity in Fe-Based Family of Superconductors and Its Electronic Structure Analysis in Presence of Dopants Rh and Pd

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Journal of Quantum Information Science 2022年第4期12卷 111-124页

作者： Ronald Columbié-Leyva Alberto López-Vivas[1† ] Ulises Miranda Ilya g. Kaplan Instituto de Investigación en Materiales UNAM CDMX México Baltic Scientific Instruments Riga Latvia

The discovered in 2008 Fe-based superconductors (SC) are a paramagnetic semimetal at ambient temperature and in some cases they become superconductor upon doping. In spite of so many years since its discovery it is still not known the mechanism that leads to superconductivity. The electronic structure study is used for determining key features of the SC mechanism in these materials. The calculations were performed using the modern suite of programs MOLPRO 2021. We performed quantum calculations of a cluster embedded in a background charge distribution that represents the infinite crystal. The Natural Population Analysis was used for determining the charge and spin distribution in the studied materials. As follows from our results, the possible mechanism for superconductivity corresponds to the RVB theory proposed by Anderson for high Tc superconductivity in cuprates.

关键词： Iron-Based High-Tc Superconductors Superconductivity Embeded Cluster Method Natural Bonding Orbitals Analysis

Design of small-scale gradient coils in magnetic resonance imaging by using the topology optimization method

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Chinese Physics B 2018年第5期27卷 91-100页

作者：潘辉贾峰刘震宇 Maxim Zaitsev Juergen Hennig Jan g Korvink Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China University of Chinese Academy of Sciences Beijing 100049 China Deptartment of Radiology Medical Physics Medical Center University of Freiburg Faculty of Medicine University of Freiburg Freiburg 79106 Germany Institute of Microstructure Technology Karlsruhe Institute of Technology (KIT) Karlsruhe 76344 Germany

A topology optimization method based on the solid isotropic material with penalization interpolation scheme is utilized for designing gradient coils for use in magnetic resonance microscopy. Unlike the popular stream function method, the proposed method has design variables that are the distribution of conductive material. A voltage-driven transverse gradient coil is proposed to be used as micro-scale magnetic resonance imaging（MRI） gradient coils, thus avoiding introducing a coil-winding pattern and simplifying the coil configuration. The proposed method avoids post-processing errors that occur when the continuous current density is approximated by discrete wires in the stream function approach. The feasibility and accuracy of the method are verified through designing the z-gradient and y-gradient coils on a cylindrical *** design results show that the proposed method can provide a new coil layout in a compact design space.

关键词： topology optimization method gradient coils solid isotropic material with penalization magnetic resonance imaging

Improving bermudagrass in the Southeastern United States with alfalfa as an alternative nitrogen source in grazing systems

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grassland Research 2022年第4期1卷 280-289页

作者： Justin C.Burt Lisa L.Baxter Christopher g.Prevatt Mary Kimberly Mullenix R.Lawton Stewart Jr. Jennifer J.Tucker Department of Animal and Dairy Science University of GeorgiaTiftonGeorgiaUSA Department of Crop and Soil Science University of GeorgiaTiftonGeorgiaUSA Regional Specialized Agent Range Cattle RECUniversity of FloridaGainesvilleFloridaUSA Department of Animal Science Auburn UniversityAuburnAuburnUSA Department of Animal and Dairy Science University of GeorgiaAthensGeorgiaUSA

Background Bermudagrass(Cynodon spp.)is one of the most common perennial warm-season forages grown in the Southeastern United *** incorporation of alfalfa(Medicago sativa)into bermudagrass pastures could serve as an alternative source of nitrogen(N)while also improving the nutritive value of the forage *** A 2-year grazing evaluation arranged in a randomized complete block design was conducted from May to September 2018(Year 1)and May–August 2019(Year 2)in Tifton,gA,*** objective was to compare the production of alfalfa–bermudagrass mixed pastures(BgA)with bermudagrass monoculture pastures with(BgN)or without(Bg)the application of synthetic nitrogen on forage production and stocker cattle *** Differences were observed for average daily gain(p=0.10),gain per hectare(p=0.02)and stocking rate(p=0.01),in that BgA was greatest compared to BgN and Bg,which did not differ from each ***,BgA had increased forage crude protein(p=0.01)and total digestible nutrients(p=0.01)compared to BgN and ***,BgA provided the greatest economic return per hectare compared to Bg or *** These data illustrate improved animal performance and forage nutritive value using alfalfa–bermudagrass systems and offer a viable option for producers seeking alternatives to synthetic N sources for bermudagrass pastures in the Southeastern United States.

关键词： alfalfa-bermudagrass mixtures forage management grazing management

The potency of N,N′-diphenyl-1,4-phenylenediamine and adiposederived stem cell co-administration in alleviating hepatorenal dysfunction complications associated with type 1 diabetes mellitus in rats

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BIOCELL 2023年第8期47卷 1885-1895页

作者： HANY M.ABD EL-LATEEF SAFA H.QAHL EMAN FAYAD SARAH A.ALTALHI IBRAHIM JAFRI EL SHAIMAA SHABANA MARWA K.DARWISH REHAB MAHER SAAD SHAABAN SHADY g.EL-SAWAH Department of Chemistry College of ScienceKing Faisal UniversityAl-AhsaSaudi Arabia Chemistry Department Faculty of ScienceSohag UniversitySohagEgypt Department of Biology College of ScienceUniversity of JeddahJeddahSaudi Arabia Department of Biotechnology College of ScienceTaif UniversityTaifSaudi Arabia Fellow of Biochemistry Genetic UnitChildren HospitalFaculty of MedicineMansoura UniversityMansouraEgypt Chemistry Department(Biochemistry Branch) Faculty of ScienceSuez UniversitySuezEgypt Department of Clinical Laboratories Sciences College of Applied Medical SciencesShaqra UniversityRiyadhSaudi Arabia Biology Department Faculty of ScienceMansoura UniversityMansouraEgypt Department of Chemistry Organic Chemistry DivisionCollege of ScienceMansoura UniversityMansouraEgypt Zoology Department Faculty of ScienceArish UniversityNorth SinaiEgypt

Background:The increasing occurrence of diabetes mellitus(DM)noted worldwide has considerably elicited concern in the recent *** is associated with elevated vascular complications,morbidity,mortality,and poor quality of *** this context,mesenchymal stem cells(MSCs)have shown significant therapeutic potentialities in managing and curing type 1 DM owing to their self-renewable,immunosuppressive,and differentiation *** investigated the potential action of N,N′-diphenyl-1,4-phenylenediamine(DPPD),a well-known synthetic antioxidant to enhance the therapeutic ability of the adipose-derived stem cells(AD-MSCs)in alleviating kidney and liver complications in diabetic ***:Over the four weeks of experiments,albino male rats(n=36)were split into six test groups:control,DPPD(250 mg/kg,i.p.),STZ-diabetic(D),D+DPPD,D+AD-MSCs(1×10^(6)cell/rat,i.v.),and D+AD-MSCs+DPPD treated ***:Significant declines in the renal and hepatic oxidative stress markers(MDA,ROS,and AgEs)were observed coupled with a significant elevation in many antioxidant marker levels(gSH,SOD,CAT,gPx,HO-1,and TAC)in the diabetic rats treated with either DPPD or AD-MSCs or their co-administered injection compared to the diabetic untreated *** was suggested to be the leading cause of amelioration of the kidney functions(as measured by urea,uric acid,and creatine levels)and liver functions(as evidenced by the levels of AST,ALT,ALP,bilirubin,total proteins,albumin,and globulins).Conclusion:DPPD and AD-MSCs co-administration showed superior results in terms of the enhancement of the relative hepato-renal function,indicating the beneficial role of DPPD supplementation in increasing the therapeutic potential of AD-MSCs.

关键词： Antioxidants Diabetic nephropathy DPPD Oxidative stress Stem cells

Effect of promoters on dynamics of gas-solid fluidized bed——Statistical and ANN approaches

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China Particuology 2007年第6期5卷 401-407页

作者： Y.K. Mohanty K.C. Biswal g.K. Roy B.P. Mohanty Department of Chemical Engineering GIET Gunupur 765 022 Rayagada Orissa India Department of Chemical Engineering NIT Rourkela 769008 Orissa India

In this study, a bubbling fluidized bed column, 99 mm in inside diameter and 960 mm in height, was used to investigate the effect of rod and disc promoters on fluctuation and expansion ratios. Factorial design （statistical approach） and artificial neural network （ANN） models were developed to predict the fluctuation and expansion ratios in this gas-solid fluidized bed with varying gas flow rates, bed heights, particle sizes and densities. The fluctuation and expansion predicted using these statistical and ANN models, for beds with and without promoters, were found to agree well with corresponding experiments. The statistical model was found to be superior to the ANN model due to its ability to take into account both individual and interactive effects. The rod promoters were found to be more effective in reducing bed fluctuation, and in increasing bed expansion at high gas mass velocities.

关键词： gas-solid fluidized bed Fluctuation ratio Expansion ratio Promoter Factorial design Artificial neural network