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.

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Layered group IV monochalcogenides are two-dimensional (2D) semiconducting materials with unique crystal structures and novel physical properties. Here, we report the growth of single crystalline GeS microribbons using the chemical vapor transport process. By using conductive atomic force microscopy, we demonstrated that the conductive behavior in the vertical direction was mainly affected by the Schottky barriers between GeS and both electrodes. Furthermore, we found that the topographic and current heterogeneities were significantly different with and without illumination. The topographic deformation and current enhancement were also predicted by our density functional theory (DFT)-based calculations. Their local spatial correlation between the topographic height and current was established. By virtue of 2D fast Fourier transform power spectra, we constructed the holistic spatial correlation between the topographic and current heterogeneity that indicated the diminished correlation with illumination. These findings on layered GeS microribbons provide insights into the conductive and topographic behaviors in 2D materials.

Vertical Conductivity and Topography in Electrostrictive Germanium Sulfide Microribbon via Conductive Atomic Force Microscopy.

This article reviews several classes of high-quality inorganic semiconductor nanomaterials for high-performance flexible and stretchable electronics in two- or three-dimensional layouts Approaches for fabricating inorganic semiconductors in the forms of wires, ribbons, and membranes, and methods for integrating these materials on flexible substrates are presented Finally, perspectives on the trends for future work related to flexible electronics are described


Keywords:

flexible electronics;
inorganic semiconductor nanomaterials;
top-down approach;
dry transfer printing;
thin-film transistor;
stretchable electronics;
3-D heterogeneous integrated circuits

Inorganic Semiconductor Nanomaterials for High‐Performance Flexible Electronics

The present invention provides optical devices and systems fabricated, at least in part, via printing-based assembly and integration of device components. In specific embodiments the present invention provides light emitting systems, light collecting systems, light sensing systems and photovoltaic systems comprising printable semiconductor elements, including large area, high performance macroelectronic devices. Optical systems of the present invention comprise semiconductor elements assembled, organized and/or integrated with other device components via printing techniques that exhibit performance characteristics and functionality comparable to single crystalline semiconductor based devices fabricated using conventional high temperature processing methods. Optical systems of the present invention have device geometries and configurations, such as form factors, component densities, and component positions, accessed by printing that provide a range of useful device functionalities. Optical systems of the present invention include devices and device arrays exhibiting a range of useful physical and mechanical properties including flexibility, shapeability, conformability and stretchablity. Optical systems of the present invention include, however, devices and device arrays provided on conventional rigid or semi-rigid substrates, in addition to devices and device arrays provided on flexible, shapeable and/or stretchable substrates.

Semiconductor-based optical system and method of making the same

PROBLEM TO BE SOLVED: To provide a method and an apparatus for roll-to-roll transfer of graphene which enable transferring a large-area graphene layer, easily at low costs, to a variety of substrates having flexibility and allowing drawing, graphene roll produced by a roll-to-roll transfer step and its applications.SOLUTION: A roll-to-roll graphene transfer method comprises forming a laminate 50 including a substrate 10, a graphene layer 20 and a first flexible substrate 31 from the graphene layer 20 formed on the substrate 10 and the first flexible substrate 31 brought into contact with the graphene layer by using a first roller portion 110, transferring the graphene layer 20 to the first flexible substrate 31, while removing the substrate 10 from the laminate 50 by immersing the laminate 50 in an etching solution 60 and passing through the etching solution 60, by means of a second roller portion 120, transferring the graphene layer 20 on the first flexible substrate 31 to a second flexible substrate 32 by using a third roller portion 130 and taking up in a rolled form.

Graphene roll and element

The order-order transition temperature (T(OOT)) in blends of poly(styrene-b-isoprene-b-styrene) (S-I-S) triblock copolymer and polyisoprene (PI) homopolymer was investigated by using synchrotron small-angle X-ray scattering (SAXS). Pure triblock copolymer undergoes an order-order transition (OOT) from hexagonally ordered cylinder (HEX) to body centered cubic (BCC) phases. In order to investigate the effect of the molecular weight of the added homopolymer on T(OOT) of the triblock copolymer, various low-molecular-weight PI homopolymers were studied. The results revealed that T(OOT) was affected by the PI molecular weight. T(OOT) was reduced for blends having low-molecular-weight PI.

Jong Hyun Ahn

Papers

Vertical Conductivity and Topography in Electrostrictive Germanium Sulfide Microribbon via Conductive Atomic Force Microscopy.

Inorganic Semiconductor Nanomaterials for High‐Performance Flexible Electronics

Semiconductor-based optical system and method of making the same

Graphene roll and element

Effect of homopolymer molecular weight on order-order transition in block copolymer and homopolymer blends.