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Density functional theory study of electronic absorption spectra and intermolecular interactions of porphyrin-borate complexes

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JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM 2010年第1-3期956卷 26-32页

作者： Wang, Lan-Fen Meng, Xian-Wei Tang, Fang-Qiong Chinese Acad Sci Lab Controllable Preparat & Applicat Nanomat Tech Inst Phys & Chem Beijing 100190 Peoples R China

Electronic absorption spectra and intermolecular interactions of complexes formed between meso-tetrakis (1-methylpyridinium-4-yl) porphine (TMPyP) and borates (tetraphenylborate (TPB) anion or fluorinated derivatives of TPB (TFPB, TFMPB)), namely TMPyP-TPB, TMPyP-TFPB and TMPyP-TFMPB, are investigated by density functional theory (DFT) and time-dependent DFT (TDDFT). It is revealed that the frontier molecular orbitals and electronic transitions for TMPyP have varied when TMPyP is incorporated with borates. TDDFT calculated Q (0, 0) and B (0, 0) bands of TMPyP exhibit a large bathochromic shift when TMPyP turns from its monomeric to complexed forms, and the obtained absorption maxima are in good agreement with the experimental data. The extension of C-alpha-C-m bonds for TMPyP in complexes leads to the weakened asymmetric C-alpha-C-m stretching vibration, and then moves Q(x) (0, 1) transition to longer wavelengths. The flattening of TMPyP in complexes is suggested to be the main structural origin of the red-shift event. The calculated interaction energies between TMPyP and borates are in the range of 9.13-18.82 kcal/mol with intensity sequence of TMPyP-TPB > TMPyP-TFPB >> TMPyP-TFMPB. The C-H center dot center dot center dot pi static attraction is proposed to be mainly responsible for the stability of the complexes. (C) 2010 Elsevier B.V. All rights reserved.

关键词： TMPyP Borates DFT Electronic absorption spectra Intermolecular interactions

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Reconfigurable mesh-based inter-chip optical interconnection network for distributed-memory multiprocessor system

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OPTIK 2010年第20期121卷 1845-1847页

作者： Yu, Zhihua Luo, Fengguang Li, Bin Zhou, Weilin Zong, Liangjia Tao, Qing Huazhong Univ Sci & Technol Coll Optoelect Sci & Engn Wuhan 430074 Hubei Peoples R China Wuhan Natl Lab Optoelect Wuhan 430074 Peoples R China

A 4 x 4 reconfigurable mesh-based inter-chip optical interconnection network is reported for distributed-memory multiprocessor system and the experiment confirmed that the data rate in each channel could reach above 3 125 Gbps which would be a good solution to solve the communication bottlenecks between processors Each node of this reconfigurable mesh could realize 15 Internal connection patterns to complete the interconnections of processors Besides this mesh interconnect network via ultra-high bandwidth waveguides embedded in EOPCB can realize flexible multiprocessor system architecture options (C) 2009 Elsevier GmbH All rights reserved

关键词： Reconfigurable mesh (R mesh) Optical interconnection Distributed memory multiprocessor Electro optical printed circuit board (EOPCB)

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Burst expansion, distribution and diversification of MITEs in the silkworm genome

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BMC GENOMICS 2010年第1期11卷 520-520页

作者： Han, Min-Jin Shen, Yi-Hong Gao, Ying-Hui Chen, Li-Yong Xiang, Zhong-Huai Zhang, Ze Third Med Univ Inst Surg Res Dept Anesthesiol Chongqing 400042 Peoples R China Third Med Univ Daping Hosp Chongqing 400042 Peoples R China Southwest Univ Minist Agr Key Sericultural Lab Chongqing 400715 Peoples R China Chongqing Univ Inst Agr & Life Sci Chongqing 400044 Peoples R China

Background: Miniature inverted-repeat transposable elements (MITEs) are widespread in plants and animals. Although silkworm (Bombyx mori) has a large amount of and a variety of transposable elements, the genome-wide information of the silkworm MITEs is unknown. Results: We used structure-based and homology approaches to search for MITEs in the silkworm genome. We identified 17 MITE families with a total of 5785 members, accounting for similar to 0.4% of the genome. 7 of 17 MITE families are completely novel based on the nucleotide composition of target site duplication (TSD) and/or terminal inverted repeats (TIR). Silkworm MITEs were widely and nonrandom distributed in the genome. One family named BmMITE-2 might experience a recent burst expansion. Network and diversity analyses for each family revealed different diversification patterns of the silkworm MITEs, reflecting the signatures of genome-shocks that silkworm experienced. Most silkworm MITEs preferentially inserted into or near genes and BmMITE-11 that encodes a germline-restricted small RNA might silence its the closest genes in silkworm ovary through a small RNA pathway. Conclusions: Silkworm harbors 17 MITE families. The silkworm MITEs preferred to reside in or near genes and one MITE might be involved in gene silence. Our results emphasize the exceptional role of MITEs in transcriptional regulation of genes and have general implications to understand interaction between MITEs and their host genome.

关键词： Terminal Inverted Repeat Target Site Duplication Miniature Inverted Repeat Transposable Element Close Gene Silkworm Genome

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Performance-asymmetry-aware scheduling for Chip Multiprocessors with static core coupling

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JOURNAL OF SYSTEMS ARChiTECTURE 2010年第10期56卷 534-542页

作者： Dong, Jianbo Zhang, Lei Han, Yinhe Yan, Guihai Li, Xiaowei Chinese Acad Sci Inst Comp Technol Key Lab Comp Syst & Architecture Beijing Peoples R China Chinese Acad Sci Grad Univ Beijing Peoples R China

Thread-level redundancy is an efficient approach for transient fault detection and recovery in Chip Multiprocessors (CMPs), in which two adjacent cores are statically coupled to form a functional Dual Modular Redundancy (DMR). Manufacturing process variations cause core-to-core (C2C) performance asymmetry across the chip, which can be further divided into the asymmetry among core-pairs and the asymmetry within a core-pair. We call them inter- and intra-pair asymmetries, respectively, both of which should be taken into considerations in application scheduling for CMPs with static core coupling. In this paper, we first formulate the above scheduling problem as a 0-1 programming problem to maximize the system Weighted Throughput. An efficient IVF&AppSen algorithm is then proposed, which we prove to be optimal when the number of applications equals to that of core-pairs. We also adapt the Simulated Annealing technique to tackle this problem when applications are less than core-pairs on chip. Simulations on a 64-core CMP shows that the proposed algorithms achieve 2.5-9.3% improvement in Weighted Throughput when compared to prior VarF&AppIPC algorithm. (C) 2010 Elsevier B.V. All rights reserved.

关键词： Process variation Thread-level redundancy Chip Multiprocessor Scheduling

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Genetic Engineering of Stenotrophomonas Strain YC-1 To Possess a Broader Substrate Range for Organophosphates

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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010年第11期58卷 6762-6766页

作者： Yang, Chao Song, Cunjiang Mulchandani, Ashok Qiao, Chuanling Univ Calif Riverside Dept Chem & Environm Engn Riverside CA 92521 USA Chinese Acad Sci State Key Lab Integrated Management Pest Insects Inst Zool Beijing 100101 Peoples R China Nankai Univ Dept Microbiol Coll Life Sci Tianjin 300071 Peoples R China

In this work, Stenotrophomonas sp. strain YC-1, a native soil bacterium that produces methyl parathion hydrolase (MPH), was genetically engineered to possess a broader substrate range for organophosphates (OPs). A surface anchor system derived from the truncated ice nucleation protein (INPNC) from Pseudomonas syringae was used to target organophosphorus hydrolase (OPH) onto the cell surface of strain YC-1, reducing the potential substrate uptake limitation. The surface localization of INPNC OPH was verified by cell fractionation, Western blot, proteinase accessibility, and immunofluorescence microscopy. No growth inhibition was observed for the engineered strain, and suspended cultures retained almost 100% activity over a period of 2 weeks. Concomitant expression of OPH in strain YC-1 resulted in a recombinant strain capable of simultaneously degrading diethyl and dimethyl OPs. A mixture of six OP pesticides (0.2 mM each) could be degraded completely within 5 h. The broader substrate specificity in combination with the rapid degradation rate makes this engineered strain a promising candidate for in situ remediation of OP-contaminated sites.

关键词： Organophosphate detoxification organophosphorus hydrolase methyl parathion hydrolase Stenotrophomonas

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Differences between karyotypically normal and abnormal human embryonic stem cells

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CELL PROLIFERATION 2010年第3期43卷 195-206页

作者： Yang, S. Lin, G. Tan, Y. -Q. Deng, L. -Y. Yuan, D. Lu, G. -X. Cent S Univ Inst Reprod & Stem Cell Engn Changsha Peoples R China Natl Engn Res Ctr Human Stem Cells Changsha Peoples R China

Objectives: To compare different biological characteristics of human embryonic stem cells (HESCs) between those with normal and those with abnormal karyotype. Materials and methods: Culture-adapted HESCs (chHES-3) with abnormal karyotype were compared with karyotypically normal cells, with regard to pluripotency and differentiation capacity, ultrastructure, growth characteristics, gene expression profiles and signalling pathways. Results: We found a new abnormal karyotype of HESCs. We observed that chHES-3 cells with normal and abnormal karyotypes shared similarities in expression markers of pluripotency;however, karyotypically abnormal chHES-3 cells had a tendency for differentiation towards ectoderm lineages and were easily maintained in suboptimal culturing conditions. Abnormal chHES-3 cells displayed relatively mature cell organelles compared to normal cells, and karyotypically abnormal chHES-3 cells had increased survival and population growth. Genes related to cell proliferation and apoptosis were up-regulated, but genes associated with genetic instability (p53, Rb, BRCA1) were down-regulated in the karyotypically abnormal cells. Conclusion: Karyotypically abnormal chHES-3 cells had a more developed capacity for proliferation, resistance to apoptosis and less genetic stability compared to normal chHES-3 cells and may be an excellent model for studying and characterizing initial stages that determine transition of embryonic stem cells into cancer stem cells.

关键词： EMBRYONIC stem cells KARYotYPES GENE expression CELL proliferation CANCER cells

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Experimental demonstration of a single-carrier frequency division multiple address based PON (SCFDMA-PON) architecture

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OPTICS EXPRESS 2010年第24期18卷 24556-24564页

作者： Zhang, Cheng Li, Juhao Zhang, Fan He, Yongqi Wu, Hequan Chen, Zhangyuan Peking Univ State Key Lab Adv Opt Commun Syst & Networks Beijing 100871 Peoples R China

We introduce a novel architecture for next generation passive optical network (PON) base on the Single-carrier Frequency Division Multiple Address (SC-FDMA) technique. Both downstream and upstream SCFDMA-PON transmissions (5 Gb/s total, 2.5 Gb/s for each user) are experimentally demonstrated over 22.2 km standard single mode fiber and an additional simulated 1:32 optical splitter. We also test the tolerance range of the synchronization error and prove it matches the cyclic prefix period in our scheme, which means the packet transmission accuracy from different optical network units can be relaxed in the upstream. (C) 2010 Optical Society of America

关键词： Optical networks Optical signals Orthogonal frequency division multiplexing Signal processing Single mode fibers Wavelength division multiplexing

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CFD based determination of crop transpiration in local greenhouses in eastern china

CFD based determination of crop transpiration in local green...

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4th International Conference on Bioinformatics and Biomedical Engineering (iCBBE)

作者： Sun, Huaiwei Yang, Jinzhong Wang, Xiugui Wuhan Univ State Key Lab Water Resources & Hydropower Engn S Wuhan Hubei Peoples R China

ISBN: (纸本)9781424447138

Environmental control programs are beginning to implement water resources control strategies based on transpiration models. Most transpiration studies of greenhouse crops have been undertaken under cold conditions in northern and central Europe. The ventilation process in a local plastic greenhouse was studied using three-dimensional computational fluid dynamics (CFD). A simple greenhouse crop transpiration model related to ventilation characteristic of the local greenhouse in eastern china is presented in this paper. The simulated greenhouse crop transpiration has a good agreement with the measurement data.

关键词： water resource management CFD transpiration ventilation

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Seal-based secure boot scheme for trusted computing platform

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Journal of china Universities of Posts and Telecommunications 2010年第SUPPL. 2期17卷 16-21页

作者： Song, Cheng Peng, Wei-Ping Xin, Yang Luo, Shou-Shan Zhu, Hong-Liang Information Security Center Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Network and Information Attack and Defence Technology Beijing University of Posts and Telecommunications Beijing 100876 China Beijing Safe-Code Technology Co. Ltd Beijing 100876 China

Secure boot is one important way to ensure the security of system for the terminal computing platform. The existing solutions for platform secure boot are based on verification by matching the reference measurements with the runtime measurements. These solutions are complex and inefficient. Based on the existing secure boot scheme, a secure boot model based on trusted personal computer (PC) is designed. Through the use of the existing trusted computing technology, a seal-based secure boot scheme for trusted computing platform is proposed in this paper. In this scheme, it is not necessary to generate the certificates on components of the reference measurements;it is also not necessary for verification proxy to verify the integrity of the runtime measurements. At the same time, the security of platform system is effectively guaranteed during booting. © 2010 The Journal of china Universities of Posts and Telecommunications.

关键词： Trusted computing

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EMMNet: Sensor Networking for Electricity Meter Monitoring

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SENSORS 2010年第7期10卷 6307-6323页

作者： Lin, Zhi-Ting Zheng, Jie Ji, Yu-Sheng Zhao, Bao-Hua Qu, Yu-Gui Huang, Xu-Dong Jiang, Xiu-Fang Univ Sci & Technol China Sch Comp Sci & Technol Hefei 230027 Anhui Peoples R China State Key Lab Networking & Switching Technol Beijing 100876 Peoples R China Natl Inst Informat Tokyo 1018430 Japan

Smart sensors are emerging as a promising technology for a large number of application domains. This paper presents a collection of requirements and guidelines that serve as a basis for a general smart sensor architecture to monitor electricity meters. It also presents an electricity meter monitoring network, named EMMNet, comprised of data collectors, data concentrators, hand-held devices, a centralized server, and clients. EMMNet provides long-distance communication capabilities, which make it suitable suitable for complex urban environments. In addition, the operational cost of EMMNet is low, compared with other existing remote meter monitoring systems based on GPRS. A new dynamic tree protocol based on the application requirements which can significantly improve the reliability of the network is also proposed. We are currently conducting tests on five networks and investigating network problems for further improvements. Evaluation results indicate that EMMNet enhances the efficiency and accuracy in the reading, recording, and calibration of electricity meters.

关键词： smart sensor electricity meter monitoring dynamic tree protocol application

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