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

Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.

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Electronics and optoelectronics of two-dimensional transition metal dichalcogenides.

The semiconductor ZnO has gained substantial interest in the research community in part because of its large exciton binding energy (60meV) which could lead to lasing action based on exciton recombination even above room temperature. Even though research focusing on ZnO goes back many decades, the renewed interest is fueled by availability of high-quality substrates and reports of p-type conduction and ferromagnetic behavior when doped with transitions metals, both of which remain controversial. It is this renewed interest in ZnO which forms the basis of this review. As mentioned already, ZnO is not new to the semiconductor field, with studies of its lattice parameter dating back to 1935 by Bunn [Proc. Phys. Soc. London 47, 836 (1935)], studies of its vibrational properties with Raman scattering in 1966 by Damen et al. [Phys. Rev. 142, 570 (1966)], detailed optical studies in 1954 by Mollwo [Z. Angew. Phys. 6, 257 (1954)], and its growth by chemical-vapor transport in 1970 by Galli and Coker [Appl. Phys. ...

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A comprehensive review of zno materials and devices

We present an all-oxide solar cell fabricated from vertically oriented zinc oxide nanowires and cuprous oxide nanoparticles. Our solar cell consists of vertically oriented n-type zinc oxide nanowires, surrounded by a film constructed from p-type cuprous oxide nanoparticles. Our solution-based synthesis of inexpensive and environmentally benign oxide materials in a solar cell would allow for the facile production of large-scale photovoltaic devices. We found that the solar cell performance is enhanced with the addition of an intermediate oxide insulating layer between the nanowires and the nanoparticles. This observation of the important dependence of the shunt resistance on the photovoltaic performance is widely applicable to any nanowire solar cell constructed with the nanowire array in direct contact with one electrode.

Nanowire-based All Oxide Solar Cells

Novel and significantly simplified procedures for fabrication of fully integrated nanoelectrospray emitters have been described. For nanofabricated monolithic multinozzle emitters (NM2 emitters), a bottom up approach using silicon nanowires on a silicon sliver is used. For microfabricated monolithic multinozzle emitters (M3 emitters), a top down approach using MEMS techniques on silicon wafers is used. The emitters have performance comparable to that of commercially-available silica capillary emitters for nanoelectrospray mass spectrometry.

Monolithic Multinozzle Emitters for Nanoelectrospray Mass Spectrometry

Nanofluidic devices are taught incorporating inorganic nanotubes fluidly coupled to channels or nanopores for supplying a fluid containing chemical or biochemical species. In one aspect, two channels are fluidly interconnected with a nanotube. Electrodes on opposing sides of the nanotube establish electrical contact with the fluid therein. A bias current is passed between the electrodes through the fluid, and current changes are detected to ascertain the passage of select molecules, such as DNA, through the nanotube. In another inventive aspect, a gate electrode is located proximal the nanotube between the two electrodes thus forming a nanofluidic transistor. The voltage applied to the gate controls the passage of ionic species through the nanotube selected as either or both ionic polarities. In either of these aspects the nanotube can be modified, or functionalized, to control the selectivity of detection or passage.

Inorganic nanotubes and devices fabricated therefrom

We theoretically demonstrate that metals can be useful for increasing the quality factor and confinement factor of a zinc oxide (ZnO) nanocavity. For small cavities, the advantages of low radiation loss and significant mode confinement due to metal coating outweigh the disadvantage of absorption loss from metal and efficiently lower the threshold material gain. The performances of ZnO cavities without metal coating, with aluminum (Al) coating, and with silver (Ag) coating are investigated. The results indicate that while surface-wave-like plasmonic modes are lossy due to metal loss, the performances of well-confined dielectric modes are indeed improved significantly as a result of metal. Both Al and Ag can significantly reduce the threshold material gain of the uncoated ZnO cavity from 16 613 cm-1 to less than 5000 cm-1. In particular, the threshold material gain of Ag-coated cavity is reduced to only 3206 cm-1.

Metal-Coated Zinc Oxide Nanocavities

A process for altering the thermoelectric properties of an electrically conductive material is provided. The process includes providing an electrically conducting material and a substrate. The electrically conducting material is brought into contact with the substrate. A thermal gradient can be applied to the electrically conducting material and a voltage applied to the substrate. In this manner, the electrical conductivity, the thermoelectric power and/or the thermal conductivity of the electrically conductive material can be altered and the figure of merit increased.

Peidong Yang

Papers

Nanowire-based All Oxide Solar Cells

Monolithic Multinozzle Emitters for Nanoelectrospray Mass Spectrometry

Inorganic nanotubes and devices fabricated therefrom

Metal-Coated Zinc Oxide Nanocavities

Process for altering thermoelectric properties of a material