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

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

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

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

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

Interferometers have a long and distinguished history, and have been at the centre of many important developments in physics and metrology, such as Young's doubleslit experiment, the Michelson–Morley experiment and the atomic clock. The unique advantage of interferometry is that the wavelength or frequency of the radiation used acts as an inherently precise measuring device.

Atom interferometer that puts noise in the shade

In this paper, we investigate the manipulation of quasi-1D Bose gases that are trapped in a highly elongated potential by optimal control methods. The effective meanfield dynamics of the gas can be described by a one-dimensional non-polynomial Schr\"odinger equation. We extend the indirect optimal control method for the Gross-Pitaevskii equation by Winckel and Borzi (2008) to obtain necessary optimality conditions for state and energy cost functionals. This approach is then applied to optimally compress a quasi-1D Bose gase in an (optical) box potential, i.e., to find a so-called short-cut to adiabaticity, by solving the optimality conditions numerically. The behavior of the proposed method is finally analyzed and compared to simple direct optimization strategies using reduced basis functions. Simulations results demonstrate the feasibility of the proposed approach.

Optimal control of quasi-1D Bose gases in optical box potentials

We used argon atoms in the metastable long-lived 1s/sub 5/ state. This state has a transition (at 801 nm) where the excited state decays predominately (70%) to the ground state. Varying the detuning of a 801-nm standing light wave, we could thus realize any real, complex, or imaginary sinusoidal potential for the metastable argon atoms. Our detector can only register the metastable state, and therefore atoms pumped to the ground state will escape detection. We performed experiments studying the coherent motion of atoms in crystals.

Tailored periodic potentials in atom optics

Potentials for atoms can be created by external fields acting on properties like magnetic moment, charge, polarizability, or by oscillating fields which couple internal states. The most prominent realization of the latter is the optical dipole potential formed by coupling ground and electronically excited states of an atom with light. Here we present an experimental investigation of the remarkable properties of potentials derived from radio-frequency (RF) coupling between electronic ground states. The coupling is magnetic and the vector character allows to design state dependent potential landscapes. On atom chips this enables robust coherent atom manipulation on much smaller spatial scales than possible with static fields alone. We find no additional heating or collisional loss up to densities approaching 10 atoms / cm compared to static magnetic traps. We demonstrate the creation of Bose-Einstein condensates in RF potentials and investigate the difference in the interference between two independently created and two coherently split condensates in identical traps. All together this makes RF dressing a powerful new tool for micro manipulation of atomic and molecular systems.

06 08 22 8 v 1 2 9 A ug 2 00 6 Radio-frequency dressed state potentials for neutral atoms

Photons play a central role in performing general communication tasks. For long distance communications, photons will be lost on the way to receiver, and naturally a quantum communication system then needs to be equipped with functions to overcome the photon losses and to correct errors. We present several quantum repeater schemes and their potential implementation, and compare the advantages and disadvantages of each.

Jörg Schmiedmayer

Papers

Atom interferometer that puts noise in the shade

Optimal control of quasi-1D Bose gases in optical box potentials

Tailored periodic potentials in atom optics

06 08 22 8 v 1 2 9 A ug 2 00 6 Radio-frequency dressed state potentials for neutral atoms

Quantum communication utilizing cavity-based quantum devices