There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346

Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology.

Surface plasmons are waves that propagate along the surface of a conductor. By altering the structure of a metal's surface, the properties of surface plasmons--in particular their interaction with light--can be tailored, which offers the potential for developing new types of photonic device. This could lead to miniaturized photonic circuits with length scales that are much smaller than those currently achieved. Surface plasmons are being explored for their potential in subwavelength optics, data storage, light generation, microscopy and bio-photonics.

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Surface plasmon subwavelength optics

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

We present a study of computational through-wall imaging using a dynamically reconfigurable metasurface antenna (DMA). The DMA consists of a single-feed, electrically-large microstrip line, loaded with individually addressable metamaterial radiators. Each metamaterial resonator is integrated with a diode, enabling it to be switched on (radiating) or off (non-radiating) by an externally applied voltage. By switching subsets of the array of elements on or off, spatially diverse radiation patterns are formed that are scattered by the wall and structures beyond the wall. Images can be reconstructed from these measurements, using a combination of range migration algorithms and wall compensation algorithms, with minimal frequency bandwidth requirements; even single frequency measurements are possible in conjunction with the DMA. We investigate imaging through a variety of wall materials at K-band frequencies (18-26.5 GHz), including homogeneous media with known properties and inhomogeneous materials such as plywood. We further investigate single-frequency performance against full-bandwidth measurements. The DMA used here is electrically large in one dimension, over which many spatially diverse measurements can be taken. By scanning the DMA in the perpendicular direction, full two-dimensional scans can be acquired with minimal cost and time, making the one-dimensional DMA attractive as the basis for future through-wall scanning systems.

Computational through-wall imaging using a dynamic metasurface antenna

Metasurfaces: Large-Area Metasurface Perfect Absorbers from Visible to Near-Infrared (Adv. Mater. 48/2015)

Using wireless communication infrastructure to recognize human behaviors has achieved great success over the last decade. This article presents the opportunities and challenges posed by a novel class of antennas referred to as DMA for wireless sensing. In contrast to conventional solutions that rely on either frequency diversity or spatial diversity for sensing, the proposed system exploits the antenna pattern diversity and software programmability of the DMA to achieve high-performance wireless sensing. We present a general framework for DMA-based wireless sensing, and demonstrate the feasibility and benefits of the DMA in sensing using custom hardware. We identify several research challenges and future directions to fully realize this new concept.

Wireless Sensing Using Dynamic Metasurface Antennas: Challenges and Opportunities

Carbon nanotubes interact strongly with light — a property that makes them ideal components of holographic devices. The realization of such a device opens up fresh opportunities for holography.

Optics: Nanotube holograms

The Indian Space Research Organisation (ISRO) Chandrayaan-1 mission is India's first lunar spacecraft, containing a
suite of instruments to carry out high-resolution remote sensing of the Moon at visible, near infrared and X-ray
wavelengths. Due for launch in early 2008, the spacecraft will carry out its two year mission in a polar orbit around the
Moon at an altitude of 100 km. One of the eleven instruments in the spacecraft payload is the Chandrayaan-1 X-ray
Spectrometer (C1XS), a descendant of the successful D-CIXS instrument that flew on the European Space Agency
SMART-1 lunar mission launched in 2003. C1XS consists of 24 swept-charge device (SCD) silicon X-ray detectors
arranged in 6 modules that will carry out high quality X-ray spectroscopic mapping of the Moon using the technique of
X-ray fluorescence. This paper presents an overview of the Chandrayaan-1 mission and specifically the C1XS
instrument and describes the development of an SCD test facility, proton irradiation characterisation and screening of
candidate SCD devices for the mission.

David R. Smith

Papers

Computational through-wall imaging using a dynamic metasurface antenna

Metasurfaces: Large-Area Metasurface Perfect Absorbers from Visible to Near-Infrared (Adv. Mater. 48/2015)

Wireless Sensing Using Dynamic Metasurface Antennas: Challenges and Opportunities

Optics: Nanotube holograms

Characterisation of swept-charge devices for the Chandrayaan-1 x-ray spectrometer (C1XS) instrument