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Phosphine oxide-functionalized polyfluorene derivatives:synthesis,photophysics,electrochemical properties,and electroluminescence performance

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science China Chemistry 2011年第4期54卷 678-684页

作者： LIU DeAng GIBsON gary BRUG James LAM sity MAO samuel s Lawrence Berkeley National Laboratory and Department of Mechanical Engineering University of CaliforniaBerkeleyCAUSA Information surfaces Lab Hewlett Packard LabsHewlett Packard Company1501 Page Mill RoadPalo AltoCA 94304USA

A series of phosphine oxide-functionalized polyfluorene derivatives,PFH-PO-40-1 (P1),PFH-PO-20-1 (P2),PFH-PO-10-1 (P3),and PFH-PO-1-1 (P4),were prepared via a palladium-mediated suzuki cross-coupling *** structures and purities of all polymers were fully characterized by 1H and 13C NMR,UV-vis and photoluminescent spectroscopy,gel permeation chromatography,and TGA/*** emission features showed single broad peaks at about 445 nm in film,compared with those in dilute solutions,which might be caused by some degree of aggregation in the excited states of the *** best electroluminescence (EL) performance of these polymers with configuration of ITO/PEDOT:Pss/Polymer/Alq3/LiF/Al was obtained from P1 (current efficiency was 4.2 Cd/A at 6V).

关键词：电致发光性能聚芴衍生物电化学性能官能化氧化膦光物理凝胶渗透色谱法聚合物结构

Potential hybrid feedstock for biodiesel production in the tropics

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Frontiers in Energy 2016年第3期10卷 329-336页

作者： solomon GIWA Oludaisi ADEKOMAYA collins NWAOKOCHA Department of Agricultural and Mechanical Engineering College of Engineering and Environmental Studies Olabisi Onabanjo UniversityIbogun Campus Ifo 234039 Nigeria

Recently, mixture of different oils at various proportions have been used as feedstock for biodiesel production. The primary aim is to improve fuel properties which are strongly influenced by the fatty acid composition of the individual oil that makes up the feedstock mix. The tropics are renowned for abundant oil-bearing crops of which palm kernel oil （PKO） from palm seed and groundnut oil （GNO） are prominent. This present paper investigated biodiesel production from hybrid oil （HO） of PKO （medium carbon chain and highly saturated oil） and GNO （long carbon chain and highly unsaturated oil） at 50/ 50 （v/v） blending. The principal fatty acids （FAs） in the HO are oleic （35.62%） and lauric acids （24.23%） with 47.80% of saturated FA and 52.26% of unsaturated FA contents. The chemical conversion of the oil to methyl ester （ME） gave 86.56% yield. Fuel properties of hybrid oil methyl ester （the HOME） were determined in accordance with standard test methods and were found to comply with both AsTM D6751 and EN 14214 standards. The oxidative stability, cetane number and kinematic viscosity （KV） of HOME were observed to be improved when compared with those of GNO methyl ester from single parent oil, which could be accredited to the improved FA composition of the HO. The KV （3.69 minE/s） of HOME obtained in this paper was remarkably low compared with those reported in literature for most biodiesels. This value suggests better flow, atomization, spray and combustion of this fuel. Conclusively, the binary blend of oils can be a viable option to improve the fuel properties ofbiodiesel feedstock coupled with reduced cost.

关键词： groundnut oil palm kernel oil methyl ester,fuel properties tropics fatty acid composition

Electrical stimulation and denervated muscles after spinal cord injury

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Neural Regeneration Research 2020年第8期15卷 1397-1407页

作者： subhalakshmi Chandrasekaran John Davis Ines Bersch gary Goldberg Ashraf s.Gorgey spinal Cord Injury and Disorders Hunter Holmes McGuire VA Medical CenterRichmondVAUSA swiss Paraplegic Centre NottwilSwitzerland Institute of Clinical sciences Department of Orthopedics at the University of GothenburgGothenburgSweden Department of Physical Medicine and Rehabilitation Virginia Commonwealth UniversityRichmondVAUSA Electrodiagnostic Center Hunter Holmes McGuire VA Medical CenterRichmondVAUSA

spinal cord injury(sCI)population with injury below T10 or injury to the cauda equina region is characterized by denervated muscles,extensive muscle atrophy,infiltration of intramuscular fat and formation of fibrous *** morphological changes may put individuals with sCI at higher risk for developing other diseases such as various cardiovascular diseases,diabetes,obesity and ***,there is no available rehabilitation intervention to rescue the muscles or restore muscle size in sCI individuals with lower motor neuron ***,hereby,performed a review of the available evidence that supports the use of electrical stimulation in restoration of denervated muscle following *** pulse width stimulation(LPWs)technique is an upcoming method of stimulating denervated *** primary objective is to explore the best stimulation paradigms(stimulation parameters,stimulation technique and stimulation wave)to achieve restoration of the denervated *** parameters,such as the pulse duration,need to be 100–1000 times longer than in innervated muscles to achieve desirable excitability and *** use of electrical stimulation in animal and human models induces muscle *** in animal models indicate that electrical stimulation,with a combination of exercise and pharmacological interventions,have proven to be effective in improving various aspects like relative muscle weight,muscle cross sectional area,number of myelinated regenerated fibers,and restoring some level of muscle *** studies have shown similar outcomes,identifying the use of LPWs as an effective strategy in increasing muscle cross sectional area,the size of muscle fibers,and improving muscle ***,displaying promise is an effective future stimulation *** summary,LPWs is a novel stimulation technique for denervated muscles in humans with *** studies on LPWs of denervated muscles will help in translating

关键词： denervation DXA electrical stimulation LMN injury LPWs MRI spinal cord injury stimulation parameters

NON sPURIOUs sPECTRAL-LIKE ELEMENT METHODs FOR MAXWELL's EQUATIONs

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Journal of Computational Mathematics 2007年第3期25卷 282-304页

作者： gary Cohen Marc Duruflé INRIA Domaine de VoluceauRocquencourt-BP 10578153 Le Chesnay CedexFrance

In this paper, we give the state of the art for the so called “mixed spectral elements” for Maxwell＇s equations. several families of elements, such as edge elements and discon-tinuous Galerkin methods （DGM） are presented and discussed. In particular, we show the need of introducing some numerical dissipation terms to avoid spurious modes in these methods. such terms are classical for DGM but their use for edge element methods is novel approach described in this paper. Finally, numerical experiments show the fast and low-cost character of these elements.

关键词： Maxwell's equations Discontinuous Galerkin methods Edge elements Masslumping.

Macrophages in immunoregulation and therapeutics

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signal Transduction and Targeted Therapy 2023年第6期8卷 I0002-I0002,2821-2854页

作者： shanze Chen Abdullah F.U.H.saeed Quan Liu Qiong Jiang Haizhao Xu gary Guishan Xiao Lang Rao Yanhong Duo Department of Respiratory Diseases and Critic Care Unit Shenzhen Institute of Respiratory DiseaseShenzhen Key Laboratory of Respiratory DiseaseShenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen518020China Department of Cancer Biology Beckman Research Institute of City of Hope National Medical CenterLos AngelesCA91010USA Department of Laboratory Medicine Huazhong University of Science and Technology Union Shenzhen Hospital(Nanshan Hospital)Shenzhen UniversityShenzhen518052China Department of Respiratory The First Affiliated HospitalSchool of MedicineSouthern University of Science and TechnologyShenzhen518055China state Key Laboratory of Fine Chemicals Department of Pharmaceutical SciencesSchool of Chemical EngineeringDalian University of TechnologyDalianChina Institute of Biomedical Health Technology and Engineering Shenzhen Bay LaboratoryShenzhen518132China Department of Microbiology Tumor and Cell Biology(MTC)Karolinska InstitutetStockholmSweden

Macrophages exist in various tissues,several body cavities,and around mucosal surfaces and are a vital part of the innate immune system for host defense against many pathogens and *** possess binary M1/M2 macrophage polarization settings,which perform a central role in an array of immune tasks via intrinsic signal cascades and,therefore,must be precisely *** crucial questions about macrophage signaling and immune modulation are yet to be *** addition,the clinical importance of tumor-associated macrophages is becoming more widely recognized as significant progress has been made in understanding their ***,they are an integral part of the tumor microenvironment,playing a part in the regulation of a wide variety of processes including angiogenesis,extracellular matrix transformation,cancer cell proliferation,metastasis,immunosuppression,and resistance to chemotherapeutic and checkpoint blockade ***,we discuss immune regulation in macrophage polarization and signaling,mechanical stresses and modulation,metabolic signaling pathways,mitochondrial and transcriptional,and epigenetic ***,we have broadly extended the understanding of macrophages in extracellular traps and the essential roles of autophagy and aging in regulating macrophage ***,we discussed recent advances in macrophages-mediated immune regulation of autoimmune diseases and ***,we discussed targeted macrophage therapy to portray prospective targets for therapeutic strategies in health and diseases.

关键词： becoming polarization Macrophages

Detecting the linkage between arable land use and poverty using machine learning methods at global perspective

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Geography and sustainability 2022年第1期3卷 7-20页

作者： Fuyou Tian Bingfang Wu Hongwei Zeng gary R Watmough Miao Zhang Yurui Li state Key Laboratory of Remote sensing science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China school of Geosciences University of EdinburghEH89XP EdinburghUnited Kingdom Institute of Geographic sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional sustainable Development Modelling Chinese Academy of SciencesBeijing 100101China

Eradicating extreme poverty is one of the UN’s primary sustainable development goals(sDG).Arable land is related to eradicating poverty(sDG1)and hunger(sDG2).However,the linkage between arable land use and poverty reduction is ambiguous and has seldom been investigated *** indicators of agricultural inputs,crop intensification and extensification were used to explore the relationship between arable land use and ***-parametric machine learning methods were used to analyze the linkage between agriculture and poverty at the global scale,including the classification and regression tree(CART)and random forest *** found that the yield gap,fertilizer consumption and potential cropland ratio in protected areas correlated with *** countries usually had a ratio of actual to potential yield less than 0.33 and fertilizer consumption less than 7.31 kg/***,crop extensification,intensification and agricultural inputs were related to poverty at the global level.

关键词： Arable land use Poverty Machine learning Yield gap Random forest

Folded Mos2 layers with reduced interlayer coupling

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Nano Research 2014年第4期7卷 572-578页

作者： Andres Castellanos-Gomez Herre s. J. van der Zant gary A. steele Kavli Institute of Nanoscience Delft University of Technology 2528 CJ Delft The Netherlands

We study molybdenum disulfide (Mos2) structures generated by folding single-layer and bilayer Mos2 flakes. We find that this modified layer stacking leads to a decrease in the interlayer coupling and an enhancement of the photoluminescence emission yield. We additionally find that folded single-layer Mos2 structures show a contribution to photoluminescence spectra of both neutral and charged excitons, which is a characteristic feature of single-layer Mos2 that has not been observed in multilayer Mos2. The results presented here open the door to fabrication of multilayered Mos2 samples with high optical absorption while maintaining the advantageous enhanced photoluminescence emission of single-layer Mos2 by controllably twisting the Mos2 layers.

关键词： Mos2 层间耦合折叠光致发光光谱二硫化钼光发射单层改性层

Weak Gravity Conjecture and extremal black holes

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science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 69-86页

作者： William Cottrell gary shiu Pablo soler Department of Physics University of WisconsinMadison WI53706USA Institut fur Theoretische Physik Universitat HeidelbergPhilosophenweg19Heidelberg D-69120Germany

Motivated by the desire to improve our understanding of the Weak Gravity Conjecture, we compute the one-loop correction of charged particles to the geometry and entropy of extremal black holes in 4D. We use the entropy function formalism to extend previous analysis that dealt with neutral particles, and obtain the corrections to the horizon entropy for different regimes of black hole masses. These corrections are small in general. They are furthermore reduced when supersymmetry is present, and disappear in N = 4 supergravity. We provide some speculative arguments that in a theory with only sub-extremal particles, classical Reissner-Nordstrom black holes actually possess an infinite microcanonical entropy, though only a finite amount is visible to an external observer, as shown by the horizon entropy computation.

关键词： black holes string theory entropy

The gut microbiome: an orchestrator of xenobiotic metabolism

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Acta Pharmaceutica sinica B 2020年第1期10卷 19-32页

作者： stephanie L.collins Andrew D.Patterson Department of Biochemistry Microbiologyand Molecular Biologythe Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Veterinary and Biomedical science the Pennsylvania State UniversityUniversity ParkPA 16802USA

Microbes inhabiting the intestinal tract of humans represent a site for xenobiotic *** gut microbiome,the collection of microorganisms in the gastrointestinal tract,can alter the metabolic outcome of pharmaceuticals,environmental toxicants,and heavy metals,thereby changing their *** chemical modification of xenobiotics by the gut microbiome,either through the intestinal tract or re-entering the gut via enterohepatic circulation,can lead to increased metabolism or bioactivation,depending on the enzymatic activity within the microbial *** enzymes encoded within the microbiome include those that reverse the modifications imparted by host detoxification ***,the microbiome can limit xenobiotic absorption in the small intestine by increasing the expression of cell-cell adhesion proteins,supporting the protective mucosal layer,and/or directly sequestering ***,host gene expression is regulated by the microbiome,including CYP450s,multi-drug resistance proteins,and the transcription factors that regulate *** the microbiome affects the host and pharmacokinetics of the xenobiotic,xenobiotics can also influence the viability and metabolism of the *** understanding of the complex interconnectedness between host,microbiome,and metabolism will advance with new modeling systems,technology development and refinement,and mechanistic studies focused on the contribution of human and microbial metabolism.

关键词： Gut microbiome Xenobiotic metabolism Absorption Gastrointestinal tract Pharmacokinetics Enterohepatic circulation Bioactivation