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

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.

Synergistic Effects of Tranylcypromine and ML385: A Repurposing Strategy for Effective Cancer Therapy

This paper incorporates insights from organizational identity and identification, social network research and post-merger integration to explore factors influencing employees' identification with a merged nonprofit organization. We propose that nonprofit employees' identification with the merged nonprofit organization is associated with their network size, relational heterogeneity, and perceived effectiveness of integration processes. Empirical results suggest that employees with larger mentoring and socioemotional support networks exhibit strong post-merger identification. Relational heterogeneity within the workflow network has an inverted U-shape relationship with post-merger identification. Employees' perceived effectiveness of integration processes significantly influences their sense of identity with the new organization. Implications for better managing post-merger identification are discussed.

Nonprofit post-merger identification: Network size, relational heterogeneity, and perceived integration effectiveness

A High-Voltage Zn-Air Battery Based on an Asymmetric Electrolyte Configuration

In this paper, two conjugated polymers named PBDT-OT-BT and PBDT-DST-BT, derived from 4,8-bis(4,5-dioctylthiophen-2-yl)benzo[1,2-b : 4,5-b’]dithiophene (BDT-OT) or 4,8-bis(4,5-bis(octylthio)thiophene-2-yl)benzo[1,2-b : 4,5-b’]dithiophene (BDT-DST) as the electron-donating unit and benzo[c][1,2,5]thiadiazole (BT) as electron-withdrawing unit were synthesized and characterized. It was found that compared to the alkyl side chain substituted polymer PBDT-OT-BT, the two alkylthio side chain modified polymer PBDT-DST-BT exhibited lower highest occupied molecular orbital (HOMO) energy level, weaker crystallinity characteristic, and higher dielectric constant (ϵr) at 1 kHz. However, PBDT-DST-BT also presented relatively poor miscibility with Y6 in comparison with PBDT-OT-BT, which had a negative effect on the bulk heterojunction morphology and hindered the exciton dissociation and carrier collection. Eventually, the PBDT-DST-BT : Y6 based polymer solar cells (PSCs) achieved a power conversion efficiency (PCE) of 2.27 % much lower than that of the PBDT-OT-BT : Y6 based device (PCE=9.46 %). These results would provide a deep understanding of the influence of alkylthio side groups on the properties of polymer donors in PSCs. 

Synthesis and Characterization of Dialkylthio Side Chains Modified Benzo[1,2‐b:4,5‐b’]dithiophene‐Based Conjugated Polymer for Organic Solar Cells

A miniaturized wideband metasurface antenna with ±45° dual-polarization is proposed. The metasurface (MTS) is comprised of an array of 3 × 3 square patches. A pair of coaxial probes feeds the corner-truncated patch underneath the MTS while keeping the floor intact; ensuring that less energy is radiated in the backward direction. To realize miniaturization of the MTS radiation element and maintain dual-polarized radiation performance, each square metal patch is loaded with a symmetrical quasi-fractal slot. By changing the current path of each patch, the resonant frequency of the MTS is decreased, and the electrical size is reduced. Characteristic mode analysis (CMA) is utilized to explain and analyze the miniaturization mechanism of the MTS. In order to prove the theoretical results, a prototype with the radiation element size of 0.39λ0 × 0.39λ0 (λ0 is the wavelength in free space at the center operating frequency) is fabricated. The measured bandwidth is 18.6% (4.98–6.00 GHz) with |S11| < −10 dB, |S12| < −16 dB, boresight gain of 6.12–7.45 dBi and front-to-back ratio better than 20 dB.

Mingwei Chen

Papers

Synergistic Effects of Tranylcypromine and ML385: A Repurposing Strategy for Effective Cancer Therapy

Nonprofit post-merger identification: Network size, relational heterogeneity, and perceived integration effectiveness

A High-Voltage Zn-Air Battery Based on an Asymmetric Electrolyte Configuration

Synthesis and Characterization of Dialkylthio Side Chains Modified Benzo[1,2‐b:4,5‐b’]dithiophene‐Based Conjugated Polymer for Organic Solar Cells

Miniaturized Wideband ±45° Dual-Polarized Metasurface Antenna by Loading Quasi-Fractal Slot