Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Fast parallel algorithms for short-range molecular dynamics

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

The generation of acoustic waves in a PZT film and on the surface of a bulk single crystal sample of barium titanate through impulsive stimulated scattering is demonstrated. This optical method allows routine and thorough characterization of the dispersive properties of thin film acoustic modes. The potential for extraction of the elastic and piezoelectric constants of piezoelectric thin films is discussed.

Impulsive stimulated scattering spectroscopy of surface acoustic waves

The authors discuss the concept of the Brillouin zone, central to many fields of condensed matter physics. They challenge the universality of defining the Brillouin zone as a Wigner-Seitz cell of the reciprocal lattice. Experimental measurements of terahertz phonon-polariton dispersion in a photonic crystal fabricated in a thin slab of an anisotropic material (lithium niobate) demonstrate that the lowest band gap does not form at the boundary of the conventionally defined Brillouin zone, in contrast to a similar photonic crystal fabricated in a nearly isotropic lithium tantalate. The analysis motivated by this unexpected experimental result shows that in an anisotropic photonic crystal the Wigner-Seitz cell of the reciprocal lattice is no longer bounded by Bragg planes and, consequently, does not conform to the original definition of the Brillouin zone. The authors construct an alternative Brillouin zone bounded by the Bragg planes and show its utility in analyzing the dispersion bands of anisotropic photonic crystals.

What is the Brillouin zone of an anisotropic photonic crystal

Terahertz (THz) photon echoes from molecular orientation in acetonitrile vapor have been observed at room temperature. Two-dimensional (2D) rotational spectroscopy reveals third- and higher-order nonlinear rotational responses.

Two-dimensional Terahertz Photon Echo and Rotational Spectroscopy in the Gas Phase

A room-temperature polarization-sensitive CMOS terahertz camera based on quantum-dot-enhanced terahertz-to-visible photon upconversion

http://link.springer.com/content/pdf/10.1007/978-3-642-85176-6_42.pdf

Keith A. Nelson

Papers

Impulsive stimulated scattering spectroscopy of surface acoustic waves

What is the Brillouin zone of an anisotropic photonic crystal

Two-dimensional Terahertz Photon Echo and Rotational Spectroscopy in the Gas Phase

A room-temperature polarization-sensitive CMOS terahertz camera based on quantum-dot-enhanced terahertz-to-visible photon upconversion

Programmable Femtosecond-Pulse Shaping and Spectroscopy