Design and Theoretical Analyses of Tip–Insulator–Metal Structure with Bottom–Up Light Illumination: Formations of Elongated Symmetrical Plasmonic Hot Spot at Sub-10 nm Resolution

Ag tip–insulator–metal structure with bottom–up light illumination is proposed and theoretically analyzed. It shows that there is a strong plasmonic coupling between Ag tip and metallic surface. Different from oblique light illumination, this novel design possesses unique advantages of symmetrical hot spot profile and enlarged depth of focus at a sub-10-nm spatial resolution. Influences of tip size, insulator, and metallic layer thickness are studied. It is found that the metallic layer thickness greatly affects the plasmonic hot spot quality. Meanwhile, the thickness of photoresist plays a major role in controlling light spot size, indicating that much higher resolution can be achieved for the Ag tips with large curvature radius.     

Perfect Absorption of Light by Coherently Induced Plasmon Hybridization in Ultrathin Metamaterial Film

We demonstrated numerically that light can be totally absorbed by an ultrathin metamaterial film through coherently induced plasmon hybridization. Two fundamental modes, namely symmetrical and antisymmetrical modes, are observed in the metal–insulator–metal structure and attributed to the electric and magnetic resonance, respectively. Each kind of resonance is related to a distinct absorption peak for the corresponding coherent inputs. In particular, it is found that the antisymmetrical absorption is almost omnidirectional and suitable for divergent beams with arbitrary polarization and angle of incidence. To interpret the interaction of magnetic and electric fields with the structure, effective material parameters of the metamaterial are also retrieved, showing good agreement with the intuitive discussion. Furthermore, the general condition of coherent perfect absorption in a metamaterial thin film is given, which could be helpful for the design and understanding of such absorbers.     

Design of a Structured Bulk Plasmon Illumination Source for Enhancing Plasmonic Cavity Superlens Imaging

Plasmonics - A structured bulk plasmon illumination (BPI) source is designed for achieving a uniform high spatial frequency illumination field. By employing the hyperbolic metamaterial (HMM)...     

表达O型口蹄疫病毒VPl基因的重组病毒BHV-1的构建与鉴定

[目的]为了构建表达口蹄疫病毒(O/china/99)VP1基因的牛疱疹病毒1型,将人工合成的口蹄疫病毒VP1基因插入到巨细胞病毒(CMV)启动子之下构建gE基因缺失转移载体.[方法]利用磷酸钙介导转染法将该转移载体与亲本病毒BHV-1/gE-/LacZ+的基因组DNA共转染牛鼻甲细胞后收获增殖的病毒.通过筛选白色病毒蚀斑,得到重组病毒BHV-1/gE-/VP1.[结果]PCR检测结果表明VP1基因已经插入到了重组病毒BHV-1/gE-的基因组中,间接免疫荧光试验和Westem blot证实了BHV-1/gE-/VP1中的VP1基因在感染的细胞中获得了表达.[结论]本研究成功地构建了表达口蹄疫病毒VP1基因的重组病毒BHV-1/gE-/VP1,为研制口蹄疫及其他重要牛传染病的BHV-1病毒载体疫苗奠定了基础.     

《细胞生物学》课堂教学模式改革的探索与实践

为了更好地培养学生的能力,必须对传统的教学模式进行改革。针对传统教学模式下生物工程专业细胞生物学教学中学生积极性和主动性不强、缺少综合能力训练内容、作业抄袭、新知识与新进展反映不理想等问题,通过设定合理题目、规定格式和内容、单独报告、择优讲演等方式,利用学生的好胜心理、竞争性和成就感等,提出了新的教学模式。教学实践证明,新的教学模式能够充分调动学生学习的积极性和主动性,提高学生对专业知识的综合与归纳能力、表达演讲能力和电脑使用技能,同时也避免了作业抄袭现象的发生,强化了学生的自信心。另外,也对新模式中存在的问题进行了思考与建议。     

气候变化对滇西北碧塔海流域景观演变的影响

气候变化是景观演变的重要驱动力,高海拔地带生态系统对气候变化的响应较为敏感和迅速。选择地处青藏高原东南缘,受人为干扰相对较小的碧塔海流域为研究对象,利用1958—2011年气象资料以及1955、1974、1981、1994、2005和2011年6个年代的景观类型面积,采用气候倾向率估计、Mann-Kendall突变检验方法和Pearson相关系数等统计方法,研究了香格里拉县气候变化背景下碧塔海流域景观演变特征。结果表明:(1)1958—2011年来,滇西北香格里拉县多年平均气温为5.9℃,多年平均活动积温为2146.1℃,多年平均年极端高温为24.3℃,多年平均年极端低温为-18.6℃,多年平均降水量为631.7mm。气温、活动积温和年极端低温呈显著上升趋势,近54年来气温平均上升了1.94℃,升温速率远高于云南和全国水平。年极端高温和降水量呈增加趋势,但增加不明显。滇西北高原碧塔海流域背景气候呈现显著的变暖趋势。(2)1955—2011年来,碧塔海流域自然景观演变规律为草甸和灌草丛向有林地演变,气温、活动积温和年极端低温升高趋势与有林地景观面积的增加趋势大体一致,与草甸和灌草丛变化趋势相反。(3)气温、活动积温和年极端低温与碧塔海流域草甸、灌草丛和有林地的景观面积变化具有显著的相关性,是流域景观演变的主导气候要素,在草甸和灌草丛演变成有林地的过程中发挥着重要作用。极端高温和降水量对流域景观演变的作用相对较弱。     

哺乳动物克隆及其应用前景

细胞核移植一词最早出现于Ｓｐｅｍａｎｎ(1938)所著《胚胎发育与诱导》一书中,他建议把发育后期的细胞核移植到去核的卵中,以研究细胞核的发育能力,但由于当时实验条件的限制而未能够实施。直到1952年,Ｂｒｉｇｇｓ和Ｋｉｎｇ才第一次报道了蛙的胚胎细胞核移植成功。Ｇｕｒｄｏｎ(1962)将爪蟾蝌蚪期肠上皮细胞核移植到去核的卵母细胞中,重构胚胎发育成正常的个体;而将成体爪蟾的肠上皮细胞核移入去核卵母细胞中时....     

Proteomic analysis of chicken embryonic trachea and kidney tissues after infection <Emphasis Type="Italic">in ovo</Emphasis> by avian infectious bronchitis coronavirus

Background  

Avian infectious bronchitis (IB) is one of the most serious diseases of economic importance in chickens; it is caused by the avian infectious coronavirus (IBV). Information remains limited about the comparative protein expression profiles of chicken embryonic tissues in response to IBV infection in ovo. In this study, we analyzed the changes of protein expression in trachea and kidney tissues from chicken embryos, following IBV infection in ovo, using two-dimensional gel electrophoresis (2-DE) coupled with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF-TOF MS).     

Far-Field Super-Resolution Imaging of Nano-transparent Objects by Hyperlens with Plasmonic Resonant Cavity

A plasmonic resonant cavity-based hyperlens is theoretically proposed and demonstrated to achieve far-field phase contrast images of nano-transparent objects. The phase contrast super-resolution imaging is mainly contributed to the excited surface plasmons inside hyperlens and cavity structure surrounding nano-objects, which help to greatly enhance evanescent waves generated by nano-transparent objects and convert weak phase information to light intensity distribution with high contrast at the zoomed imaging plane of hyperlens. As examples, nano-dielectric object imaging is numerically demonstrated with half-pitch resolution about λ/10 and a minimum distinguishable refractive index difference down to 0.15.