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Flu channel drug resistance:a tale of two sites

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Protein & Cell 2010年第3期1卷 246-258页

作者： Rafal m.Pielak james J.Chou Department of Biological Chemistry and molecular Pharmacology Harvard Medical SchoolBostonMA 02115USA Program in Biological and Biomedical Sciences Harvard Medical SchoolBostonMA 02115USA

The m2 proteins of influenza A and B virus,Am2 and Bm2,respectively,are transmembrane proteins that oligomerize in the viral membrane to form proton-selective *** conductance of the m2 proteins is required for viral replication;it is believed to equilibrate pH across the viral membrane during cell entry and across the trans-Golgi membrane of infected cells during viral *** addition to the role of m2 in proton conductance,recent mutagenesis and structural studies suggest that the cytoplasmic domains of the m2 proteins also play a role in recruiting the matrix proteins to the cell surface during virus *** viral ion channels of minimalist architecture,the membrane-embedded channel domain of m2 has been a model system for investigating the mechanism of proton ***,as a proven drug target for the treatment of influenza A infection,m2 has been the subject of intense research for developing new anti-flu ***2 is the target of two anti-influenza A drugs,amantadine and rimantadine,both belonging to the adamantane class of ***,resistance of influenza A to adamantane is now widespread due to mutations in the channel domain of *** review summarizes the structure and function of both Am2 and Bm2 channels,the mechanism of drug inhibition and drug resistance of Am2,as well as the development of new m2 inhibitors as potential anti-flu drugs.

关键词： m2 Bm2 influenza proton channel amantadine rimantadine

Tight Rock Wettability and Its Relationship to Other Petrophysical Properties： A montney Case Study

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Journal of Earth Science 2017年第2期28卷 381-390页

作者： Ali Javaheri Hassan Dehghanpour james m.Wood University of Alberta Edmonton AB T6G 2R3 Canada Encana Corporation Calgary AB T2P 2S5 Canada

Understanding and modelling the wettability of tight rocks is essential for designing fracturing and treatment fluids. In this paper, we measure and analyze spontaneous imbibition of water and oil into five twin core plugs drilled from the cores of a well drilled in the montney Formation, an unconventional oil and gas play in the Western Canadian Sedimentary Basin. We characterize the samples by measuring the mineralogy using XRD（x-ray diffraction）, total organic carbon content, porosity, and permeability. Interestingly, the equilibrated water uptake of the five samples is similar, while, their oil uptake increases by increasing the core porosity and permeability. We define two wettability indices for the oil phase based on the slope and equilibrium values of water and oil imbibition curves. Both indices increase by increasing porosity and permeability, with the slope affinity index showing a stronger correlation. This observation suggests that part of the pore network has a stronger affinity to oil than to water. We also observe that the two indices decrease by increasing neutron porosity and gamma ray parameters measured by wireline logging tools. The samples with higher gamma ray and neutron porosity are expected to have greater clay content, and thus less effective porosity and permeability.

关键词： spontaneous imbibition wettability petrophysics gamma ray log

High energy neutron and pion-decay gamma-ray emissions from solar flares

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 11-40页

作者： Edward L.Chupp james m.Ryan Physics Department and Space Science Center in the Institute for the Study of Earth Oceans and Space University of New Hampshire

Solar flare gamma-ray emissions from energetic ions and electrons have been detected and measured to GeV energies since 1980. In addition, neutrons produced in solar flares with 100 meV to GeV energies have been observed at the Earth. These emissions are produced by the highest energy ions and electrons accelerated at the Sun and they provide our only direct （albeit secondary） knowledge about the properties of the accelerator（s） acting in a solar flare. The solar flares, which have direct evidence for pion-decay gamma-rays, are unique and are the focus of this paper. We review our current knowledge of the highest energy solar emissions, and how the characteristics of the acceleration process are deduced from the observations. Results from the RHESSI, INTEGRAL and CORONAS missions will also be covered. The review will also cover the solar flare capabilities of the new mission, FERmI GAmmA RAY SPACE TELESCOPE, launched on 2008 June II. Finally, we discuss the requirements for future missions to advance this vital area of solar flare physics.

关键词： Sun -- Flares -- Particle Acceleration-meson Production

The effect of surface roughness on claw and adhesive hair performance in the dock beetle Gastrophysa viridula

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Insect Science 2011年第3期18卷 298-304页

作者： james m. R. Bullock Walter Federle Department of Zoology University of Cambridge Downing Street Cambridge UK

Natural adhesive systems are adapted to attach to rough surfaces, but the underlying mechanisms have not been fully clarified. Attachment forces for the beetle Gastrophysa viridula were recorded on epoxy casts of surfaces with different roughness using a centrifuge device. Replicas were made of standardized polishing paper with asperity sizes ranging from 0.05 to 30 μm and of dock leaves （Rumex obtusifolius）. Beetles adhered with a safety factor of up to 36 times body weight on smooth substrates or on casts of leaves of their host plant. On the rough substrates, forces were much lower and a minimum at small scale roughness （0.05μm asperity size, with a mean safety factor of S） was observed. Removal of the claws led to a significant reduction in force for rough substrates with asperity sizes ≥ 12 μm. Attachment forces of the hairy adhesive system itself（without the claws） slightly increased from small-scale to large-scale surface roughness, but remained below the level seen on the smooth substrate. This is explained by the inability of setal tips to make full contact to the surface.

关键词： adhesion biomechanics claws locomotion roughness tribology

Development and Evaluation of Recycled Polypropylene and Bean Pod Powder Composite Biomaterial for Fused Filament Fabrication

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Advances in materials Physics and Chemistry 2023年第3期13卷 31-48页

作者： Felix Sotohou james W. mwangi james m. mutua Erick K. Ronoh Pan African University Institute for Basic Sciences Technology and Innovation Juja Kenya Department of mechatronic Engineering Jomo Kenyatta University of Agriculture and Technology Juja Kenya Department of mechanical Engineering Jomo Kenyatta University of Agriculture and Technology Juja Kenya Department of Agricultural and Biosystems Engineering Jomo Kenyatta University of Agriculture and Technology Juja Kenya

Approximately 450 million tons of plastic and agricultural waste are produced each year in the world. Only a small portion of this plastic waste is recycled, and a small portion of this agricultural waste is used as fuel or fertilizer, and the rest of this waste is left in the environment or is burned, resulting in environmental and air pollution. For proper disposal, plastic and agricultural waste can be used in the manufacture of composites as raw materials. In this study, we had evaluated the use of bean pod powder (BPp) was used as natural reinforcing filler in recycled polypropylene (rPP) based composites. BPp/rPP composite filaments were developed using the extrusion method and the samples were printed by Fused Filament Fabrication (FFF). Composites with rPP matrix containing different weight fractions of BPp (5%, 10% and 15%) were fabricated to observe and compare the mechanical properties (tensile, flexural, and compressive strength) of the filament composites. In addition, the filament surface was analyzed for roughness and particle size of bean pod powder. The results established that BPp/rPP composites exhibited better tensile, flexural, and compressive strength than rPP and pure PP. By adding 5 wt% BPp, the tensile strength of rPP increased from 20.4 mPa to 22.8 mPa. The highest flexural strength (15.05 mPa) was obtained at 5 wt% BPp among all composites and the highest compressive strength (24.5 mPa), was obtained at 10 wt% BPp. Therefore, it can be concluded that by carefully selecting the ratio of BPp to bean pod powder, it is therefore possible to positively influence the mechanical properties of the resulting composite.

关键词： Pollution Composite Fused Filament Fabrication mechanical Properties

Periodic interstellar scintillation variations of PSRs J0613-0200 and J0636+5128 associated with the Local Bubble shell

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中国科学:物理学、力学、天文学英文版 2023年第11期66卷 221-232页

作者： Yulan Liu Robert A.main Joris P.W.Verbiest Ziwei Wu Krishnakumar m.Ambalappat Jiguang Lu David J.Champion Ismael Cognard Lucas Guillemot Kuo Liu james W.mc Kee Nataliya Porayko Golam.m.Shaifullah Gilles Theureau National Astronomical Observatories Chinese Academy of SciencesBeijing100101China Fakultät für Physik Universität BielefeldBielefeld33501Germany max-Planck-Institut für Radioastronomie Bonn53121Germany Florida Space Institute University of Central FloridaOrlandoFL32826USA Station de radioastronomie de Nançay Observatoire de ParisNançay18330France Laboratoire de Physique et Chimie de l’Environnement et de l’Espace Universitéd’OrléansOrléans45071France E.A.milne Centre for Astrophysics University of HullHullHU67RXUK Centre of Excellence for Data Science Artificial Intelligence and ModellingUniversity of HullHullHU67RXUK Dipartimento di Fisica“G.Occhialini” Universitàdi Milano-BicoccaMilano20126Italy INAF-Osservatorio Astronomico di Cagliari Selargius(CA)09047Italy INFN Sezione di Milano-BicoccaMilano20126Italy

Annual variations of interstellar scintillation can be modelled to constrain parameters of the ionized interstellar *** a pulsar is in a binary system,then investigating the orbital parameters is possible through analysis of the orbital variation of *** observations carried out from 2011 to 2020 by the European Pulsar Timing Array radio telescopes,PSRs J0613-0200and J0636+5128 show strong annual variations in their scintillation velocity,while the former additionally exhibits an orbital *** theory and markov-chain-monte-Carlo methods are used to interpret these periodic *** assume a thin and anisotropic scattering screen model,and discuss the mildly and extremely anisotropic scattering *** J0613-0200is best described by mildly anisotropic scattering,while PSR J0636+5128 exhibits extremely anisotropic *** measure the distance,velocity,and degree of anisotropy of the scattering screen for our two pulsars,finding that scattering screen distances from Earth for PSRs J0613-0200 and J0636+5128 are 316_(-20)^(+28)pc and 262_(-38)^(+96)pc,*** positions of these scattering screens are coincident with the shell of the Local Bubble towards both *** associations add to the growing evidence of the Local Bubble shell as a dominant region of scattering along many sightlines.

关键词： pulsar interstellar scintillation ionized interstellar medium

most ankle sprain research is either false or clinically unimportant:A 30-year audit of randomized controlled trials

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Journal of Sport and Health Science 2021年第5期10卷 523-529页

作者： Chris m.Bleakley mark matthews james m.Smoliga School of Health Science Ulster UniversityCounty AntrimNorthern IrelandBT370QBUK School of Sport Ulster UniversityCounty AntrimNorthern IrelandBT370QBUK Department of Physical Therapy Congdon School of Health ScienceHigh Point UniversityHigh PointNC 27268USA

Background:Lateral ankle sprain is the most common musculoskeletal *** clinical research in this field is growing,there is a broader concern that clinical trial outcomes are often false and fail to translate into patient ***:We audited 30 years of experimental research related to lateral ankle sprain management(n=74 randomized controlled trials)to determine if reports of treatment effectiveness could be validated beyond statistical ***:A total of 77%of trials reported positive treatment effects,but there was a high risk of false *** trials were unregistered and relied solely on statistical significance,or lack of statistical significance,rather than on interpreting key measures of minimum clinical importance(e.g.,minimal detectable change,minimal clinically important difference).Conclusion:Future clinical trials must adopt higher standards of reporting and data *** includes consideration of the ethical responsibility to preregister their research and interpretation of clinical outcomes beyond statistical significance.

关键词： Ankle sprain False discovery mCID mDC

The modifying influence of HLA classⅡDQB1^(*)06:02 on the Streptococcus and clinical phenotype correlation among anti-Ro+mothers of children with neonatal lupus

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Genes & Diseases 2023年第4期10卷 1169-1171页

作者： Robert m.Clancy Carla J.Guthridge miranda C.marion Joel Guthridge Timothy D.Howard Peter m.Izmirly mala masson Jill P.Buyon Judith A.james Carl D.Langefeld Department of medicine Division of RheumatologyNYU Grossman School of MedicineNew YorkNY 10016USA Arthritis and Clinical Immunology Oklahoma Medical Research FoundationOklahoma CityOK 73104USA Department of Biostatistics and Data Science Wake Forest School of MedicineWinstone SalemNC 27101USA Center for Precision medicine Wake Forest School of MedicineWinstoneSalemNC 27101USA Department of Biochemistry Wake Forest School of MedicineWinstoneSalemNC 27101USA

The genus Streptococcus,a gram-positive bacterium,con-tains species associated with immune activation at morbid outcomes,including scarlet fever,endocarditis,meningitis,and rheumatic *** both stool and saliva,there is a pos-itive correlation between Streptococcus abundance and Sjogren’s syndrome(SS)and systemic lupus erythematosus(SLE).

关键词： lupus mother fever Streptococcus

Geochemical and mineralogical evaluations of coal,shale,and mine waste overburden from makum coalfield of the Northeast India

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International Journal of Coal Science & Technology 2023年第3期10卷 41-57页

作者： Nilotpol Bhuyan Nazrul Islam monikankana Saikia james CHower Binoy K.Saikia Coal and Energy Division CSIR-North East Institute of Science and TechnologyJorhatAssam 785006India Academy of Scientific and Innovative Research(AcSIR) Ghaziabad 201002India Center for Applied Energy Research University of Kentucky2540 Research Park DriveLexingtonKY 40511USA

The Cenozoic-age makum coal from northeastern India offers numerous research opportunities because of its diverse geochemical and geological *** to its high sulfur content,the coal has been found to be less useful for industrial *** can,however,serve as a hub for ongoing research on coal-based derivative *** aim of this research work is to investigate the mineralogical and geochemical compositions of the coal,mine overburden(mOB)and shale samples taken from the makum coal field and also on establishing a mutual relationship between *** characterize the geochemical controlling factors of the makum coal field,the study employs coal petrography,FTIR,mineralogical,and geochemical *** to X-ray diffraction analysis,the major minerals like quartz,kaolinite,haematite,illite,pyrite,and calcite are present in coal and *** is observed by SEm-EDS analysis as cubic-shaped particles that are smaller than a fewμm in *** presence of sulfide minerals represents a phase of pyrite *** petrography study was used to better understand the environment that existed during the formation of the plant material,which aids us in determining the quantity of detrital mineral sediment contained in the *** to the ICP-mS analysis,the samples indicate significant levels of rare earth elements including *** present study reveals higher concentrations of poten-tial hazardous elements in the coal samples,with V,Cr,Ni,Cu,and Zn content in coal being considerably enriched compared to world-average *** correlation analysis reveals that the potential hazardous elements like Co,Ni,As,and Cu are associated with pyrite as they have strong affinity towards ***,numerous minerals and rare earth elements(REEs)exist,opening up a fresh avenue for more research in the *** study also assists researchers in understanding the significance of makum coal and provides numerous ideas for coal charac

关键词： Coal geology mine waste overburden(mOB) Petrology Rare earth elements(REEs) Potentially hazardous elements(PHEs)