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BIG-BANG COSMOLOGY

Chinese Physics C 2016年第10期40卷 355-366页

作者： K.A. Olive j.A. peacock University of Minnesota University of Edinburgh

22.1. Introduction to Standard Big-Bang Model The observed expansion of the Universe [1-3] is a natural （almost inevitable） result of any homogeneous and isotropic cosmological model based on general relativity. However, by itself, the Hubble expansion does not provide sufficient evidence for what we generally refer to as the Big-Bang model of cosmology. While general relativity is in principle capable of describing the cosmology of any given distribution of matter, it is extremely fortunate that our Universe appears to be homogeneous and isotropic on large scales. Together, homogeneity and isotropy allow us to extend the Copernican Principle to the Cosmological Principle, stating that all spatial positions in the Universe are essentially equivalent.

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Expression, Imprinting, and Evolution of Rice Homologs of the Polycomb Group Genes

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Molecular Plant 2009年第4期2卷 711-723页

作者： Ming Luo Damien Platten Abed Chaudhury W.j. peacock Elizabeth S. Dennis CSIRO Plant Industry GPO BOX 1600 ACT 2601 Australia Present address: Vitagrain Uttara Model Town Dhaka Bangladesh Present address: IRRI Los Banos Laguna 4031 Philippines

Polycomb group proteins （PcG） play important roles in epigenetic regulation of gene expression. Some core PeG proteins, such as Enhancer of Zeste （E（z））, Suppressor of Zeste （12）（Su（z）12）, and Extra Sex Combs （ESC）, are conserved in plants. The rice genome contains two E（z）-Iike genes, OsiEZ1 and OsCLF, two homologs of Su（z）12, OsEMF2a and OsEMF2b, and two ESC-like genes, OsFIE1 and OsFIE2. OsFIE1 is expressed only in endosperm; the maternal copy is expressed while the paternal copy is not active. Other rice PcG genes are expressed in a wide range of tissues and are not imprinted in the endosperm. The two E（z）-Iike genes appear to have duplicated before the separation of the dicots and monocots; the two homologs of Su（z）12 possibly duplicated during the evolution of the Gramineae and the two ESC- like genes are likely to have duplicated in the ancestor of the grasses. No homologs of the Arabidopsis seed-expressed PcG genes MEA and FIS2 were identified in the rice genome. We have isolated T-DNA insertion lines in the rice homologs of three PcG genes. There is no autonomous endosperm development in these T-DNA insertion lines. One line with a T-DNA insertion in OsEMF2b displays pleiotropic phenotypes including altered flowering time and abnormal flower organs, suggesting important roles in rice development for this gene.

关键词： Polycomb group protein pseudograin imprinting development evolution panicle.

A vectorial model for the nonlinear gradient force exerted on metallic Rayleigh nanoparticles

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Chinese Optics Letters 2024年第2期22卷 207-213页

作者：朱政张聿全闵长俊 Aurèle j.LAdam H.Paul Urbach 袁小聪 Research Center for Humanoid Sensing Research Institute of Intelligent SensingZhejiang LabHangzhou 311100China Nanophotonics Research Center Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands

Optical tweezers have proved to be a powerful tool with a wide range of *** gradient force plays a vital role in the stable optical trapping of *** scalar method is convenient and effective for analyzing the gradient force in traditional optical ***,when the third-order nonlinear effect of the nano-object is stimulated,the scalar method cannot adequately present the optical response of the metal nanoparticle to the external optical ***,we propose a theoretical model to interpret the nonlinear gradient force using the vector *** combining the optical Kerr effect,the polarizability vector of the metallic nanoparticle is derived.A quantitative analysis is obtained for the gradient force as well as for the optical potential *** vector method yields better agreement with reported experimental *** suggest that this method could lead to a deeper understanding of the physics relevant to nonlinear optical trapping and binding phenomena.

关键词： gradient forces nonlinear effect metallic nanoparticles

Trickster or Colonizer： The Latent Effects of Colonialism in Efua Sutherland＇s Play The Marriage of Anansewa

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journal of Literature and Art Studies 2015年第6期5卷 399-407页

作者： j. Sunita peacock Slippery Rock University of Pennsylvania Slippery Rock PA USA

The essay analyzes the play written by the late Efua Sutherland （from Ghana） and shows the effects of colonization among the Ghanaians. First, it explores the historical inroads made by the colonizer in West African countries, such as Ghana, causing the debilitation of the culture of such countries by erasing its history. One way in which such erasure occurred was in the destruction of sacred sites of the people. Further connections will also be made to West African cultural contexts with the history of colonization in Africa and its effects on popular culture, specifically drama in countries like Ghana. Next, the essay draws upon the role of the trickster figure of Ananse, the spider who features in many West African and Caribbean folkloric traditions. Sutherland＇s play revolves around the main character of the play, Ananse, and he is likened to the trickster figure, but the essay shows how this figure is also debilitated by the colonizer. Finally, in the play, one notes that despite the main character＇s ＂victory＂ in getting his daughter married to the ＂Chief-Who-ls-Chief＇, he does it for his survival and the survival of his daughter in a world in which the latent effects of colonization has hampered the memory and culture of its people.

关键词： Africa postcolonial drama folklore history literature

Low-loss silicon core fibre platform for mid-infrared nonlinear photonics

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Light(Science & Applications) 2019年第1期8卷 202-211页

作者： Haonan Ren Li Shen Antoine F.j.Runge Thomas W.Hawkins john Ballato Ursula Gibson Anna C.peacock Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and Technology430074 WuhanChina Department of Materials Science and Engineering Clemson UniversityClemsonSC 29634USA Department of Physics Norwegian University of Science and Technology(NTNU)N-7491 TrondheimNorway Department of Applied Physics KTH Royal Institute of Technology10044 StockholmSweden The Institute of Photonics and Optical Science(IPOS) School of PhysicsUniversity of SydneySydneyNSW 2006Australia

Broadband mid-infrared light sources are highly desired for wide-ranging applications that span free-space communications to *** recent years,silicon has attracted great interest as a platform for nonlinear optical wavelength conversion in this region,owing to its low losses(linear and nonlinear)and high ***,most research in this area has made use of small core waveguides fabricated from silicon-on-insulator platforms,which suffer from high absorption losses of the use of silica cladding,limiting their ability to generate light beyond 3μ***,we design and demonstrate a compact silicon core,silica-clad waveguide platform that has low losses across the entire silicon transparency *** waveguides are fabricated from a silicon core fibre that is tapered to engineer mode properties to ensure efficient nonlinear propagation in the core with minimal interaction of the mid-infrared light with the *** waveguides exhibit many of the benefits of fibre platforms,such as a high coupling efficiency and power handling capability,allowing for the generation of mid-infrared supercontinuum spectra with high brightness and coherence spanning almost two octaves(1.6-5.3μm).

关键词： waveguide fibre nonlinear

Classical imaging with undetected photons using four-wave mixing in silicon core fibers

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Photonics Research 2023年第2期11卷 137-142页

作者： M.HUANG D.WU H.REN L.SHEN T.W.HAWKINS j.BALLATO U.j.GIBSON M.BERESNA R.SLAVíK j.E.SIPE M.LISCIDINI A.C.peacock Optoelectronics Research Centre University of SouthamptonSouthamptonSO171BJUK School of Optoelectronic Engineering and Instrumentation Science Dalian University of TechnologyDalian 116024China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Centre for Optical Materials Science and Engineering Technologies and Department of Materials Science and Engineering Clemson UniversityClemsonSouth Carolina 29634USA Department of Physics University of TorontoTorontoOntario M5S 1A7Canada Department of Physics University of PaviaI-27100 PaviaItaly

Undetected-photon imaging allows for objects to be imaged in wavelength regions where traditional components are unavailable. Although first demonstrated using quantum sources, recent work has shown that the technique also holds with classical beams. To date, however, all the research in this area has exploited parametric downconversion processes using bulk nonlinear crystals within free-space systems. Here, we demonstrate undetectedphoton-based imaging using light generated via stimulated four-wave mixing within highly nonlinear silicon fiber waveguides. The silicon fibers have been tapered to have a core diameter of915 nm to engineer the dispersion and reduce the insertion losses, allowing for tight mode confinement over extended lengths to achieve practical nonlinear conversion efficiencies(-30 dB) with modest pump powers(48 m W). Both amplitude and phase images are obtained using classically generated light, confirming the high degree of spatial and phase correlation of our system. The high powers(>10 nW) and long coherence lengths(>4 km) associated with our large fiber-based system result in high contrast and stable images.

关键词： mixing fibers nonlinear

Post-fabrication phase trimming of Mach–Zehnder interferometers by laser annealing of germanium implanted waveguides

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Photonics Research 2017年第6期5卷 97-101页

作者： XIA CHEN MILAN M.MILOSEVIC DAVID j.THOMSON ALI Z.KHOKHAR YOHANN FRANZ ANTOINE F.j.RUNGE SAKELLARIS MAILIS ANNA C.peacock GRAHAM T.REED Optoelectronics Research Centre University of Southampton

We demonstrate a novel high-accuracy post-fabrication trimming technique to fine-tune the phase of integrated Mach–Zehnder interferometers, enabling permanent correction of typical fabrication-based phase errors. The effective index change of the optical mode is 0.19 in our measurement, which is approximately an order of magnitude improvement compared to previous work with similar excess optical loss. Our measurement results suggest that a phase accuracy of 0.078 rad was achievable with active feedback control.

关键词： Post-fabrication phase trimming of Mach Zehnder interferometers by laser annealing of germanium implanted waveguides MZI

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高温对高粱出苗和胚蛋白合成的影响

园艺与种苗 1989年第1期 21-24页

作者： H.j.Ougham j.M.peacock 陈周

出苗不良是半干旱地区高粱生产受限的主要原因。已知土温高于45℃会影响高粱种子萌动及其后胚芽的伸长,致使出苗稀疏或出苗不匀。根据记载,印度、西非和南非农田的土表温度经常高于45℃,甚至有过高达60℃的记录,已证明高土温下的出苗能... 详细信息

出苗不良是半干旱地区高粱生产受限的主要原因。已知土温高于45℃会影响高粱种子萌动及其后胚芽的伸长,致使出苗稀疏或出苗不匀。根据记载,印度、西非和南非农田的土表温度经常高于45℃,甚至有过高达60℃的记录,已证明高土温下的出苗能力存在遗传变异,并鉴定出一些在55℃土温下仍能穿出土表的品系。最近,Soman等(1985)评价了几种为研究高土温下禾谷类幼苗萌动和出苗的反应而提出的技术。当土壤水分和土表硬壳为非限制因素时,此文还描述了一种筛选高粱品系穿透灼热土壤

关键词：高粱蛋白质敏感性种子繁殖器官杂交品种杂交种出苗率

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新生儿高频振荡通气治疗的远期预后

中国新生儿科杂志 2016年第2期31卷 159-160页

作者：黄晓芳冯琪 zivanovic s peacock j alcazar-paris m 北京大学第一医院儿科 100034 不详

高频振荡通气（HFOV）是减少早产儿慢性肺疾病的有效措施。2002年报告的英国多中心、随机对照振荡研究（the United kingdom oscillation study,UKOS）采用高容量通气策略的HFOV,极早产儿生后1 h内采用HFOV或常频通气（CMV）治疗未影响... 详细信息

高频振荡通气（HFOV）是减少早产儿慢性肺疾病的有效措施。2002年报告的英国多中心、随机对照振荡研究（the United kingdom oscillation study,UKOS）采用高容量通气策略的HFOV,极早产儿生后1 h内采用HFOV或常频通气（CMV）治疗未影响婴儿1岁时的肺功能,但该研究当时未评估婴儿的小气道功能。

关键词：高频振荡通气小气道功能慢性肺疾病通气策略学龄期儿童随访研究肺功能指标气道阻力观察性肺功能检测