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Annealing Response of Cold-Rolled Vanadium Microalloyed Sheet Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 404-411页

作者： John G Speer david k Matlock Robert J Glodowski A dvanced Steel Processing and Products Research Center Colorado School of MinesGoldenColorado USA East Metals (North America) LLCPittsburghPAUSA

Vanadium microalloying is widely employed in hot-rolled HSLA products;because of its relatively high solubility in austenite,vanadium plays a special role in thin-slab cast hot-rolled products where reheating is limited prior to *** cold-rolled and annealed sheet steels,vanadium technology has been employed in bake-hardenable drawing-quality steels,and in HSLA *** studies have investigated the continuous and batch annealing response of vanadium-containing cold-rolled HSLA steels,with an emphasis on aluminum and nitrogen variations (because of the special importance of nitrogen in vanadium microallyed steels,and interesting interactions between vanadium,aluminum and nitrogen).The present contribution reviews some key aspects of vanadium-microalloyed coldrolled sheet steels,and highlights the results of selected studies showing the influence of steel composition and processing.

关键词： Microalloying vanadium,bake-hardening cold rolled sheet steel

Physiological and Growth Responses of C_3 and C_4 Plants to Reduced Temperature When Grown at Low CO_2 of the Last Ice Age

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Journal of Integrative Plant Biology 2008年第11期50卷 1388-1395页

作者： Joy k.Ward david A.Myers Richard B.Thomas Department of Ecology and Evolutionary Biology University of Kansas Department of Biology West Virginia University

During the last ice age, CO2 concentration （[CO2]） was 180-200 umol/mol compared with the modern value of 380 umol/mol, and global temperatures were -8 ℃ cooler. Relatively little is known about the responses of C3 and C4 species to longterm exposure to glacial conditions. Here Abutilon theophrasti Medik. （C3） and Amaranthus retroflexus L. （C4） were grown at 200 umol/mol CO2 with current （30/24℃） and glacial （22/16℃） temperatures for 22d. Overall, the C4 species exhibited a large growth advantage over the C3 species at low [CO2]. However, this advantage was reduced at low temperature, where the C4 species produced 5x the total mass of the C3 species versus 14x at the high temperature. This difference was due to a reduction in C4 growth at low temperature, since the C3 species exhibited similar growth between temperatures. Physiological differences between temperatures were not detected for either species, although photorespiration/net photosynthesis was reduced in the C3 species grown at low temperature, suggesting evidence of improved carbon balance at this treatment. This system suggests that C4 species had a growth advantage over C3 species during low [CO2] of the last ice age, although concurrent reductions in temperatures may have reduced this advantage.

关键词： Abutilon theophrasti Amaranthus retroflexus C3 species C4 species climate change low CO2 low temperature photorespiration Pleistocene.

Disrupted Maturation of Prefrontal Layer 5 Neuronal Circuits in an Alzheimer’s Mouse Model of Amyloid Deposition

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Neuroscience Bulletin 2023年第6期39卷 881-892页

作者： Chang Chen Jing Wei Xiaokuang Ma Baomei Xia Neha Shakir Jessica k.Zhang Le Zhang Yuehua Cui Deveroux ferguson Shenfeng Qiu Feng Bai Department of Neurology Affiliated Drum Tower HospitalMedical School of Nanjing UniversityNanjing210008China Basic Medical Sciences University of Arizona College of Medicine-PhoenixPhoenixAZ85004USA

Mutations in genes encoding amyloid precursor protein(APP)and presenilins(PSs)cause familial forms of Alzheimer’s disease(AD),a neurodegenerative disorder strongly associated with *** is currently unknown whether and how AD risks affect early brain development,and to what extent subtle synaptic pathology may occur prior to overt hallmark AD *** mutant APP/PS1 over-expression mouse lines are key tools for studying the molecular mechanisms of AD *** these lines,the 5XFAD mice rapidly develop key features of AD pathology and have proven utility in studying amyloid plaque formation and amyloidβ(Aβ)-induced *** reasoned that transgenic mutant APP/PS1 over-expression in 5XFAD mice may lead to neurodevelopmental defects in early cortical neurons,and performed detailed synaptic physiological characterization of layer 5(L5)neurons from the prefrontal cortex(PFC)of 5XFAD and wild-type littermate controls.L5 PFC neurons from 5XFAD mice show early APP/Aβ***-cell patch-clamp recording at an early post-weaning age(P22–30)revealed functional impairments;although 5XFAD PFC-L5 neurons exhibited similar membrane properties,they were intrinsically less *** addition,these neurons received smaller amplitude and frequency of miniature excitatory synaptic *** functional disturbances were further corroborated by decreased dendritic spine density and spine head volumes that indicated impaired synapse *** biotinylation followed by Western blot analysis of PFC-L5 tissue revealed that 5XFAD mice showed reduced synaptic AMPA receptor subunit GluA1 and decreased synaptic NMDA receptor subunit *** with this,patch-clamp recording of the evoked L23>L5 synaptic responses revealed a reduced AMPA/NMDA receptor current ratio,and an increased level of AMPAR-lacking silent *** results suggest that transgenic mutant forms of APP/PS1 overexpression in 5XFAD mice leads to early deve

关键词： Alzheimer’s disease Mouse model Synaptic plasticity Long-term potentiation Cortical circuit Electrophysiology Learning and memory

Experimental Investigation of Thermal Performance of Novel Finned Radiators for Automotive Cooling System

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Journal of Thermal Science 2024年第5期33卷 1726-1743页

作者： SINGH Hardeep TING david S-k READER Graham ESHTIAGHI Nicky ICHIYANAGI Mitsuhisa SUZUkI Takashi Turbulence&Energy Laboratory University of WindsorWindsor N9B 3P4Canada Chemical and Environmental Engineering School of EngineeringRMIT UniversityMelbourneVictoria 3001Australia Department of Engineering and Applied Sciences Sophia UniversityTokyo 102-8554Japan

This research investigates innovative fin-type radiators for automobile engine cooling ***-channel and helical radiators,along with straight type,were analyzed for heat transfer characteristics under various *** uniqueness of this study is evident in the design of microchannel and helical *** helical radiators,the inner rod features 4/8 helical-shaped water galleries,while the outer tube frame with embedded fins remains *** contrast,the microchannel radiators have compact trapezoidal-shaped water galleries with separate fin ***,the novelty of the research is enhanced by the utilization of 3D printing technology in the manufacturing *** constant fin height analysis at varied water and air flow rate,Microchannel Water Air Radiator with fin height 10.5 mm(MCWAR10.5)depicted a higher heat transfer rate amongst the *** comparison to Straight Water Air Radiator with fin height 9.5 mm(SWAR9.5),the heat transfer rate is 30.3%and 1.3 times ***,in constant fin surface area analysis,microchannel radiator(MCWAR3.2)illustrates lower heat dissipation than Helical radiator(HWAR138)but higher than HWAR134 and Straight radiator(SWAR6).The examination of pumping loss indicated that the Micro-channel radiator outperformed helical radiators due to its lower pressure *** average pressure loss for Micro-channel radiators was 0.74 kPa,making it 1.2 times higher than that of a straight radiator(0.62 kPa),indicating a better trade-off.

关键词： heat exchangers multi-channel helical heat exchanger heat transfer 3D printing

Low-loss microwave photonics links using hollow core fibres

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Light(Science & Applications) 2022年第8期11卷 1891-1902页

作者： Xi Zhang Zitong Feng david Marpaung Eric Numkam Fokoua Hesham Sakr John Richard Hayes Francesco Poletti david John Richardson Radan Slavík Optoelectronics Research Centre University of SouthamptonSouthamptonSO171BJUK Laser Physics and Nonlinear Optics Group Faculty of Science and TechnologyMESA+Institute for NanotechnologyUniversity of TwenteEnschede7500 AEThe Netherlands

There are a host of applications in communications, sensing, and science, in which analogue signal transmission is preferred over today’s dominant digital transmission. In some of these applications, the advantage is in lower cost, while in others, it lies in superior performance. However, especially for longer analogue photonics links (up to 10 s of km), the performance is strongly limited by the impairments arising from using standard single-mode fibres (SSMF). Firstly, the three key metrics of analogue links (loss, noise figure, and dynamic range) tend to improve with received power, but this is limited by stimulated Brillouin scattering in SSMF. Further degradation is due to the chromatic dispersion of SSMF, which induces radio-frequency (RF) signal fading, increases even-order distortions, and causes phase-to-intensity-noise conversion. Further distortions still, are caused by the kerr nonlinearity of SSMF. We propose to address all of these shortcomings by replacing SSMFs with hollow-core optical fibres, which have simultaneously six times lower chromatic dispersion and several orders of magnitude lower nonlinearity (Brillouin, kerr). We demonstrate the advantages in this application using a 7.7 km long hollow-core fibre sample, significantly surpassing the performance of an SSMF link in virtually every metric, including 15 dB higher link gain and 6 dB lower noise figure.

关键词： nonlinearity microwave shortcomings

COMPETITION POLICY IN CHINA AND ITS RELEVANCE TO SMES

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Frontiers of Law in China-Selected Publications from Chinese Universities 2012年第1期7卷 21-38页

作者： Yahua Zhang david k. Round 1. School of Accounting Economics and Finance University of Southern Queensland Toowoomba Australia 2. School of Commerce University of South Australia Adelaide Australia

Competition policy has great relevance to all the firms in any economy. Even though it is unlikely that small and medium-sized enterprises （SMEs） have enough market power to constrain competition through a misuse of such power, they may still face prosecution if they are involved in a boycott of competitors or suppliers, price-fixing, output-restriction and other monopoly agreements. This article discusses antitrust issues pertaining to SMEs with a focus on China＇s Anti-Monopoly Law （AML） and its implementation rules. Contrary to the popular view that SMEs benefit from competition laws, evidence shows that they are reluctant to get involved in antitrust litigation against large firms partly because of the high legal costs involved. There is an urgent need to promote an awareness of antitrust compliance in China and to educate SMEs about the need to avoid breaching the new antitrust law and its associated regulations. In the meantime, SMEs should take full advantage of the antitrust laws to fight against the abuse of market dominance directed at them, and to gain equal opportunities to market access.

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Multicenter,randomized study to optimize bowel for colon capsule endoscopy

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World Journal of Gastroenterology 2017年第48期23卷 8615-8625页

作者： david kastenberg Wilmot C Burch Jr david P Romeo Pankaj k kashyap david C Pound Neophytos Papageorgiou Ignacio Fernández-Urien Sainz Carly E Sokach Douglas k Rex Division of Gastroenterology Thomas Jefferson University Franklin Gastroenterology PLLC Dayton Gastroenterology Inc. Pinnacle Research Group LLC Indianapolis Gastroenterology and hepatology Department of Gastroenterology American Medical Center Department of Gastroenterology Servicio de Digestivohospital de Navarra Sidney kimmel Medical College at Thomas Jefferson University Indiana University hospital

AIM To assess the cleansing efficacy and safety of a new Colon capsule endoscopy(CCE) bowel preparation *** This was a multicenter,prospective,randomized,controlled study comparing two CCE regimens. Subjects were asymptomatic and average risk for colorectal cancer. The second generation CCE system(Pill Cam? COLON 2;Medtronic,Yoqneam,Israel) was utilized. Preparation regimens differed in the 1 st and 2 nd boosts with the Study regimen using oral sulfate solution(89 m L) with diatrizoate meglumine and diatrizoate sodium solution("diatrizoate solution")(boost 1 = 60 m L,boost 2 = 30 m L) and the Control regimen oral sulfate solution(89 m L) alone. The primary outcome was overall and segmental colon cleansing. Secondary outcomes included safety,polyp detection,colonic transit,CCE completion and capsule excretion ≤ 12 h. RESULTS Both regimens had similar cleansing efficacy for the whole colon(Adequate: Study = 75.9%,Control = 77.3%;P = 0.88) and individual segments. In the Study group,CCE completion was superior(Study = 90.9%,Control = 76.9%;P = 0.048) and colonic transit was more often < 40 min(Study = 21.8%,Control = 4%;P = 0.0073). More Study regimen subjects experienced adverse events(Study = 19.4%,Control = 3.4%;P = 0.0061),and this difference did not appear related to diatrizoate solution. Adverse events were primarily gastrointestinal in nature and no serious adverse events related either to the bowel preparation regimen or the capsule were observed. There was a trend toward higher polyp detection with the Study regimen,but this did not achieve statistical significance for any size category. Mean transit time through the entire gastrointestinal tract,from ingestion to excretion,was shorter with the Study regimen while mean colonic transit times were similar for both study *** A CCE bowel preparation regimen using oral sulfate solution and diatrizoate solution as a boost agent is effective,safe,and achieved superior CCE completion.

关键词： Bowel preparation Purgative Capsule endoscopy Endoscopy Capsule colonoscopy Large intestine

Pollen morphology in Saxifraga(Saxifragaceae) from Ny-Alesund, Svalbard, Arctic, and its taxonomic significance

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Advances in Polar Science 2014年第2期25卷 105-112页

作者： YAO Yifeng Bera Subir ferguson david kay LI Chengsen State key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Department of Botany University of Calcutta Department of Paleontology University of Vienna

Pollen morphology of eight species of Saxifraga, i.e.S, cespitosa, S. oppositifolia, S. cernua, S. nivalis, S. aizoides, S. rivularis, S. hieraciifolia, and S. hirculus, collected from Ny-Alesund, Svalbard, Arctic was examined using light and scanning electron microscopy. Pollen grains of Saxifraga species are subprolate or prolate, 3-colpate, 15.4-44.4 μm in the polar axis, 11.4 34.6 μm in the equatorial axis, and show a P/E ratio 1.19-1.40. On the basis of exine ornamentation, four pollen types, viz., the S. oppositifolia type （striate without scabrae on the muff）, S. cernua type （striate with scabrae on the muri）, S. nivalis type （microreticulate and operculum absent）, and S. cespitosa type （microechinate and operculum present）, were recognized. Hierarchical cluster analysis of the pollen morphological characters indicated that pollen morphology supports the infrageneric classification of the genus Saxifraga.

关键词： Arctic Ny-Alesund pollen morphology Saxifraga Svalbard

Effects of Broussonetia papyrifera invasion and land use on vegetation characteristics in a tropical forest of Ghana

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Journal of Forestry Research 2019年第4期30卷 1363-1373页

作者： david M.Adigbli Alexander k.Anning James k.Adomako Benedicta Y.Fosu-Mensah Institute for Environment and Sanitation Studies University of GhanaLegonAccraGhana Department of Theoretical and Applied Biology Kwame Nkrumah University of Science and TechnologyKumasiGhana Department of Botany University of GhanaLegonAccraGhana

The purpose of this study was to evaluate the effects of Broussonetia papyrifera(paper mulberry)invasion and land use on the floristic composition of a dry semideciduous forest in ***-five plots(25 m×25 m each),distributed among three land uses-selectively logged(SL);abandoned farmlands(AF);and an undisturbed reference(RF)-were *** showed lower tree species richness(S),diversity(H’),evenness(S)and basal area(BA)in the SL(46,0.78,0.32 and 269.12 m2 ha-1,respectively)and AF(40,0.53,0.45,and 131.16 m^2 ha^-1)sites compared to the RF site(79,2.66,0.87,963.72 m^2 ha^-1).Similar patterns were found at the shrub layer,but no differences were observed at the herb ***-metric multidimensional scaling ordination revealed distinct species composition among the land *** two disturbed habitats,SL and AF,were associated with increased *** invasion particularly in the overstory,with importance value index and mean relative density of 45 and 65.03%,and 42 and 53.29%,***,the species was only sparsely represented in the RF *** density of *** correlated negatively with H’,S,E,BA,and native tree density and *** findings highlight the strong link between human land use(i.e.,logging and slash-andburn farming),invasion,and vegetation characteristics,and suggest the need to limit these disturbances to conserve biodiversity within tropical forest ecosystems.

关键词： Afram Headwaters Forest Reserve Broussonetia papyrifera Forest community characteristics Human-caused disturbances Plant invasion