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FAST Observations of an Extremely Active Episode of FRB 20201124A:Ⅰ.Burst Morphology

Research in Astronomy and Astrophysics 2022年第12期22卷 54-69页

作者： d.J.Zhou J.l.Han B.Zhang K.J.lee w.w.Zhu d.li w.C.Jing w.-Y.wang Y.K.Zhang J.C.Jiang J.R Niu R luo H.Xu C.F.Zhang B.J.wang J.w.Xu P.wang Z.l.Yang Y.Feng National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China CAS Key laboratory of FAST NAOCChinese Academy of SciencesBeijing 100101China department of Physics and Astronomy University of NevadaLas VegasNV 89154USA Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China department of Astronomy Peking UniversityBeijing 100871China CSIRO Space and Astronomy EppingNSW 1710Australia Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China

we report the properties of more than 600 bursts(including cluster-bursts)detected from the repeating fast radio burst(FRB)source FRB 20201124A with the Five-hundred-meter Aperture Spherical radio Telescope during an extremely active episode on UTC 2021 September 25–28,in a series of four *** observations were carried out in the band of 1.0–1.5 GHz by using the center beam of the l-band 19-beam *** monitored the source in sixteen1 hr sessions and one 3 hr session spanning 23 *** the bursts were detected during the first four *** this first paper of the series,we perform a detailed morphological study of 624 bursts using the two-dimensional frequencytime“waterfall”plots,with a burst(or cluster-burst)defined as an emission episode during which the adjacent emission peaks have a separation shorter than 400 *** duration of a burst is therefore always longer than 1 ms,with the longest up to more than 120 *** emission spectra of the sub-bursts are typically narrow within the observing band with a characteristic width of~277 *** center frequency distribution has a dominant peak at about 1091.9 MHz and a secondary weak peak around 1327.9 *** bursts show a frequencydownwarddrifting *** on the drifting patterns,we classify the bursts into five main categories:downward drifting(263)bursts,upward drifting(3)bursts,complex(203),no drifting(35)bursts,and no evidence for drifting(121)*** are introduced based on the emission frequency range in the band(low,middle,high and wide)as well as the number of components in one burst(1,2,or multiple).we measured a varying scintillation bandwidth from about 0.5 MHz at 1.0 GHz to 1.4 MHz at 1.5 GHz with a spectral index of 3.0.

关键词： (stars:)pulsars:general Physical data and Processes stars:individual(FRB 20201124A)

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Therapeutic effects of tender coconut water on oxidative stress in fructose fed insulin resistant hypertensive rats

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Asian Pacific Journal of Tropical Medicine 2012年第4期5卷 270-276页

作者： d Bhagya l Prema T Rajamohan department of Biochemistry University of Kerala.Kariavattom CampusKeralaTrivandrum695581India department of Food Science and Nutrition Agricultural CollegeVellayaniTrivandrumKeralaIndia department of Biochemistry University of Kerala Kariavattom CampusKeralaTrivandrum695581India

Objective:To investigate whether tender coconut water(TCw) mitigates oxidative stress in fructose fed hypertensive ***:Male Sprague dawley rats were fed with fructose rich diet and treated with TCw(4 ml/100 g of body weight) for 3 subsequent *** blootl pressure was measured every three days using the indirect tail cuff *** the end of the experimental period,plasma glucose and insulin,serum triglycerides and free fatly acids, lipid peroxidation markers(MdA,hydroperoxides and conjugated dienes) and the activities of antioxidant enzymes were analyzed in all the ***:Treatment with TCw significandy lowered the systolic blood pressure and reduced serum triglycerides and free fatty *** glucose and insulin levels and lipid peroxidation markers such as MdA,hydroperoxides and conjugated dienes were significantly reduced in fructose fed rats treated with *** of antioxidant enzymes are up regulated significantly in TCw treated *** analysis of liver showed that TCw treatment reduced the lipid accumulation and inflammatory infiltration without any significant hepatocellular ***:The overall results suggest that, TCw treatment could prevent and reverse high blood pressure induced by high fructose diet probably by inhibition of lipid peroxidation,upregulation of antioxidant status and improved insulin sensitivity.

关键词： Tender coconut water Hypertension Oxidative stress Hyperinsulinemia lipid peroxidation Histopathology

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Immune dysfunction in acute alcoholic hepatitis

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world Journal of Gastroenterology 2015年第42期21卷 11904-11913页

作者： Ashwin d dhanda Peter l Collins School of Clinical Sciences University of Bristol NIHR Academic Clinical lecturer in Hepatology Institute of Translational and Stratified Medicine Plymouth University Peninsula Schools of Medicine and Dentistry South west liver Unit Plymouth Hospitals NHS Trust department of liver Medicine University Hospitals Bristol NHS Foundation Trust

Acute alcoholic hepatitis(AAH) is a serious complication of alcohol misuse and has high short term mortality. It is a clinical syndrome characterised by jaundice and coagulopathy in a patient with a history of recent heavy alcohol use and is associated with profound immune dysfunction with a primed but ineffective immune response against pathogens. Here, we review the current knowledge of the pathogenesis and immune defects of AAH and identify areas requiring further study. Alcohol activates the immune system primarily through the disruption of gut tight junction integrity allowing the escape of pathogenassociated molecular particles(PAMPs) into the portal venous system. PAMPs stimulate cells expressing toll-like receptors(mainly myeloid derived cells) and initiate a network of intercellular signalling by secretion of many soluble mediators including cytokines and chemokines. The latter coordinates the infiltration of neutrophils, monocytes and T cells and results in hepatic stellate cell activation, cellular damage and hepatocyte death by necrosis or apoptosis. On the converse of this immune activation is the growing evidence of impaired microbial defence. Neutrophils have reduced phagocytic capacity and oxidative burst and there is recent evidence that T cell exhaustion plays a role in this.

关键词： Alcoholic hepatitis Alcoholic liver disease Toll-l

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Electron Structure and Microwave Absorbing Ability of Flaky FeSiAl Powders

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Journal of Materials Science & Technology 2011年第2期27卷 170-174页

作者： T.d.Zhou d.F.liang l.J.deng d.C.luan Xihua University Chengdu 610039China State Key laboratory of Electronic Thin Films & Integrated devices University of Electronic Science and Technology of ChinaChengdu 610054China

Soft magnetic metallic materials have been w.d.l. used for absorbing electromagnetic *** Fe 86 t Si t Al 14（t=9,11,14 and 16） alloys powders were prepared from melt-quenched ribbons by annealing and *** a previous report we discussed the order-disordered structure of this *** this article,we studied their electron *** electron numbers of（111） and（100） plane increase with increasing Si content but Bohr magneton *** permittivity and complex permeability are both decreased with increasing Si content *** lowest value of reflectivity among the four alloys is originated from Fe 70 Si 14 Al *** peak values of reflectivity are all lower than 10 dB,and the absorbing frequency range（R 10 dB） increases from 1 to 2 GHz when t reaches 16.

关键词： Flaky powders Specific saturation magnetism Bohr magneton Absorbing ability

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diet medication and beta-glucanase affect ileal digesta soluble betaglucan molecular weight,carbohydrate fermentation,and performance of coccidiosis vaccinated broiler chickens given wheatbased diets

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Animal Nutrition 2023年第4期15卷 288-296页

作者： Namalika d.Karunaratne Henry l.Classen Andrew Gvan Kessel Michael R.Bedford Nancy P.Ames Rex w.Newkirk department of Animal and Poultry Science University of SaskatchewanSaskatoonSK S7N5A8Canada AB Vista MarlboroughWiltshireSN84ANUnited Kingdom Agriculture and Agri-Food Canada WinnipegR3T 2E1ManitobaCanada

Exogenous enzymes as alternatives to feed antibiotics in poultry has become an emerging research area with the emergence of antibiotic *** objective was to evaluate the effects of diet medication(antibiotics)andβ-glucanase(BGase)on digesta solubleβ-glucan depolymerization,carbohydrate fermentation,and performance of coccidiosis-vaccinated broiler chickens fed wheat-based diets.A total of 1,782 broilers were raised on litter floor pens,and each treatment was assigned to 1 pen in each of the9 *** 3 dietary treatments were based on wheat as the sole grain(control,control+medication and control+0.1%BGase),and the birds were fed the respective treatments ad libitum from 0 to 33 *** were arranged in a randomized complete block design and analyzed as a one-way ***-glucanase reduced the peak molecular weight,weight average molecular weight(Mw)and maximum molecular weight for the smallest 10%β-glucan molecules(Mw-10%)in ileal digesta at d 11and 33,whereas diet medication reduced Mw and Mw-10%at d 33 compared to the control(Plucanase and medication reduced the ileal viscosity at d 11 compared to the control(P=0.010).Ileal propionic acid concentration at d 11 and caecal total SCFA,acetic,and butyric acid concentrations at d 33 were lower in the BGase-supplemented diet than in the control(Pdded diet had higher duodenal p H compared to the control at d 33(P=0.026).The effect of medication on carbohydrate fermentation was *** medication increased weight gain after d 11,whereas BGase increased the gain for the total trial period compared to the control(Pd intake was not affected by the dietary *** and BGase improved feed efficiency after d 11 compared to the control(Pdiet medication was larger than BGase,considering weight gain and feed efficiency after d 11(Plusion,diet medication and BGase depolymerized high molecular weight ileal solubleβ-g

关键词： Beta-glucan Prebiotic Non-starch polysaccharide Soluble fiber Feed antibiotic

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<110> Fiber Texture Evolution of Ferrite wires during drawn-torsion and drawn-annealing-torsion Process

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Journal of Materials Science & Technology 2012年第11期28卷 1010-1014页

作者： Y.d. liu Y.d. Zhang A. Tidul l. Zuo Key laboratory for Anisotropy and Texture of Materials (Ministry of Education) Northeastern University Shenyang110004 China letam/Isgmp CNRS Metz 57000 France

In this paper, the texture and microstructure evolution of drawn-torsion and drawn-annealing-torsion ferrite wires are studied by electron back scattering diffraction （EBSd） in order to investigate the special torsion texture evolution. Compared to the simulation results, the stable texture components {110}〈 110 〉 and {110}〈112〉 in both drawn-torsion and drawn-annealing-torsion wires display different evolution processes. The texture of the drawn-annealing-torsion wire fits to the Taylor model. A special texture evolution is found in drawn-torsion wires, related to the grain shape, and the heterogeneous deformation. A new plastic deformation viewpoint is suggested based on the special microstructure of drawn ferrite wire.

关键词： Texture Electron back scattering diffraction (EBSd) Torsion Plastic deformation

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Effect of nitrogen on deposition and field emission properties of boron-doped micro-and nano-crystalline diamond films

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Nano-Micro letters 2010年第3期2卷 154-159页

作者： l.A.li S.H.Cheng H.d.li Q.Yu J.w.liu X.Y.lv State Key laboratory of Superhard Materials Jilin University

In this paper,we report the effect of nitrogen on the deposition and properties of boron doped diamond films synthesized by hot filament chemical vapor *** diamond films consisting of micro-grains(nano-grains) were realized with low(high) boron source flow rate during the growth *** transition of micro-grains to nano-grains is speculated to be strongly(weekly) related with the boron(nitrogen) flow *** grain size and Raman spectral feature vary insignificantly as a function of the nitrogen introduction at a certain boron flow *** variation of electron field emission characteristics dependent on nitrogen is different between microcrystalline and nanocrystalline boron doped diamond samples,which are related to the combined phase composition,boron doping level and texture *** is an optimum nitrogen proportion to improve the field emission properties of the boron-doped films.

关键词： Chemical vapor deposited diamond film Nitrogen effect Boron doping Microcrystalline Nanocrystalline Electron field emission

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dual-energy X-ray absorptiometry scans accurately predict differing body fat content in live sheep

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Journal of Animal Science and Biotechnology 2019年第1期10卷 248-253页

作者： david w Miller Ellen J Bennett Joanne l Harrison Fiona Anderson Clare l Adam School of Veterinary and life Sciences Murdoch University Scotland’s Rural College (SRUC) Peter Wilson Building The Faculty of Health University of Tasmania School of Biological Sciences University of Aberdeen Rowett Institute of Nutrition and Health University of Aberdeen

Background: There is considerable interest in implementing mobile scanning technology for on-farm body composition analysis on live *** experiments evaluated the use of dual energy X-ray absorptiometry(dXA) as an accurate method of total body fat measurement in live ***: In Exp.1,visceral and whole body fat analysis was undertaken in sheep with body condition scores(BCS)in the range 2 to 3.25(scale 1: thin to 5: fat).The relationship of BCS was moderately correlated with visceral fat depot mass(r = 0.59,P d whole body fat(r = 0.70,P with BCS in the range 2.25 to 3.75 were blood sampled to analyse circulating leptin concentrations,and were dXA scanned immediately post mortem for total body *** leptin concentrations had low correlations with BCS(r = 0.50,P d dXA body fat(r = 0.42,P d no correlation with chemical body fat(r = 0.17,P > 0.05,n = 9).There was a moderate correlation between dXA body fat and BCS(r = 0.70,P d dXA body fat was highly correlated with chemical body fat(r = 0.81,P dXA scans,at 8-week intervals,was performed on growing sheep over a 32-week *** average BCS ranged from 2.39 ± 0.07(S.E.M.) to 3.05 ± 0.11 and the dXA body fat(%) ranged from 16.8 ± 0.8 to 24.2 ± *** was a moderate correlation between dXA body fat and BCS over the 32 weeks(r = 0.61,P lusions: Overall,these experiments indicated that there was good agreement between BCS,dXA and chemical analysis for measuring total body fat in sheep,and that dXA scanning is a valid method for longitudinal measurement of total body fat in live sheep.

关键词： BCS dEXA Fat leptin longitudinal Sheep

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Time-resolved, defect-hosted, trace element mobility in deformedwitwatersrand pyrite

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Geoscience Frontiers 2019年第1期10卷 55-63页

作者： denis Fougerouse Steven M.Reddy Christopher l.Kirkland david w.Saxey william d.Rickard Robert M.Hough School of Earth and Planetary Sciences The Institute for Geoscience Research (TIGeR) Curtin University Geoscience Atom Probe Advanced Resource Characterisation Facility John de Laeter Centre Curtin University CSIRO Minerals Resources

The Pb isotopic composition of rocks is w.d.l. used to constrain the sources and mobility of melts and hydrothermal fluids in the Earth's crust. In many cases, the Pb isotopic composition appears to represent mixing of multiple Pb reservoirs. However, the nature, scale and mechanisms responsible for isotopic mixing are not well known. Additionally, the trace element composition of sulphide minerals are routinely used in ore deposit research, mineral exploration and environmental studies, though little is known about element mobility in sulphides during metamorphism and deformation. To investigate the mechanisms of trace element mobility in a deformed witwatersrand pyrite(FeS_2), we have combined electron backscatter diffraction(EBSd) and atom probe microscopy(APM). The results indicate that the pyrite microstructural features record w.d.l. different Pb isotopic compositions, covering the entire range of previously published sulphide Pb compositions from the witwatersrand basin. we show that entangled dislocations record enhanced Pb, Sb, Ni, Tl and Cu composition likely due to entrapment and short-circuit diffusion in dislocation cores. These dislocations preserve the Pb isotopic composition of the pyrite at the time of growth(~3 Ga) and show that dislocation intersections, likely to be common in deforming minerals, limit trace element mobility. In contrast, Pb, As, Ni, Co, Sb and Bi decorate a highangle grain boundary which formed soon after crystallisation by sub-grain rotation *** isotopic composition within this boundary indicates the addition of externally-derived Pb and trace elements during greenschist metamorphism at ~2 Ga. Our results show that discrete Pb reservoirs are nanometric in scale, and illustrate that grain boundaries may remain open systems for trace element mobility over 1 billion years after their formation.

关键词： Atom probe microscopy Nanoscale Nanogeochronology Microstructure Isotope geochemistry Common Pb

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PROPERTIES, wEldABIlITY ANd APPlICATIONS OF AdVANCEd wROUGHT SUPERAllOYS FOR GAS TURBINE ENGINES

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Acta Metallurgica Sinica(English letters) 2005年第1期18卷 1-14页

作者： d.l. Klarstrom V.R. Ishwar M.d. Rowe Haynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USA

Alloy selection and alloy design both require consideration of an array of material attributes, including in-service properties, weldability and fabricability. Critical properties of advanced wrought superalloys for gas turbine applications include high temperature strength, thermal stability, oxidation resistance and fatigue resistance. In this paper, the properties of twelve wrought solid-solution-strengthened and six age-hardenable superalloys are compared. weldability is an important attribute and can be a major limiting factor in the use of certain alloys. weldability test methods are discussed and the resistance of alloys to solidification cracking and strain-age cracking is compared. The use of weldability testing in the development of modern wrought su-peralloys is discussed with several examples cited. Finally, alloy selection for gas turbine components is outlined, taking into account both alloy properties and fabricability.

关键词： wrought superalloys mechanical properties strain-age cracking of weldments selection and application of wrought superalloys

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