355 research outputs found

    Molecular First Hyperpolarizabilities of a New Class of Asymmetric Squaraine Dyes

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    The molecular first hyperpolarizabilities (β) of a series of asymmetric squaraine dyes have been measured by electric-field-induced second harmonic generation; the dyes have negative β-values whose magnitudes are comparable to 4-N,N-dimethylamino-4′-nitrostilbene (DANS)

    Purification of bacteriophage M13 by anion exchange chromatography

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    M13 is a non-lytic filamentous bacteriophage (phage). It has been used widely in phage display technology for displaying foreign peptides, and also for studying macromolecule structures and interactions. Traditionally, this phage has been purified by cesium chloride (CsCl) density gradient ultracentrifugation which is highly laborious and time consuming. In the present study, a simple, rapid and efficient method for the purification of M13 based on anion exchange chromatography was established. A pre-packed SepFast™ Super Q column connected to a fast protein liquid chromatography (FPLC) system was employed to capture released phages in clarified Escherichia coli fermented broth. An average yield of 74% was obtained from a packed bed mode elution using citrate buffer (pH 4), containing 1.5 M NaCl at 1 ml/min flow rate. The purification process was shortened substantially to less than 2 h from 18 h in the conventional ultracentrifugation method. SDS-PAGE revealed that the purity of particles was comparable to that of CsCl gradient density ultracentrifugation method. Plaque forming assay showed that the purified phages were still infectious

    Unsymmetrical squaraines for nonlinear optical materials

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    Compositions for use in non-linear optical devices. The compositions have first molecular electronic hyperpolarizability (.beta.) either positive or negative in sign and therefore display second order non-linear optical properties when incorporated into non-linear optical devices

    Detection of hepatitis B virus core antigen by phage display mediated TaqMan real-time immuno-PCR

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    The core antigen (HBcAg) of hepatitis B virus (HBV) is one of the markers for the identification of the viral infection. The main purpose of this study was to develop a TaqMan real-time detection assay based on the concept of phage display mediated immuno-PCR (PD-IPCR) for the detection of HBcAg. PD-IPCR combines the advantages of immuno-PCR (IPCR) and phage display technology. IPCR integrates the versatility of enzyme-linked immunosorbent assay (ELISA) with the sensitivity and signal generation power of PCR. Whereas, phage display technology exploits the physical association between the displayed peptide and the encoding DNA within the same phage particle. In this study, a constrained peptide displayed on the surface of an M13 recombinant bacteriophage that interacts tightly with HBcAg was applied as a diagnostic reagent in IPCR. The phage displayed peptide and its encoding DNA can be used to replace monoclonal antibody (mAb) and chemically bound DNA, respectively. This method is able to detect as low as 10 ng of HBcAg with 108 pfu/ml of the recombinant phage which is about 10,000 times more sensitive than the phage-ELISA. The PD-IPCR provides an alternative means for the detection of HBcAg in human serum samples

    From Teachers’ Views to Explore the Implementation of Energy Education in Taiwan’s Elementary Schools

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    This study intended to explore the implementation of promoting “energy education” in Taiwan’s elementary schools. The research adopted a questionnaire (Likert five-point scale) from teachers’ view in three dimensions to construct examination. The 45 participants come from 10 different primary schools distributed across Taiwan, which participate in energy education program in the second period (2015-2017). The data was analyzed by ANOVA, mean and standard deviations of the viewpoints of the participants in the energy education learning achievement of the primary schools. The first findings in this research is, the program of energy education was most effective in “energy attitude” (M=4.282, SD=0.814), followed by “energy awareness” (M=4.049, SD=0.720) and “energy behavior” (M=3.983, SD=0.875). It shows that students have positive energy attitude, but they were relatively weak at energy saving behavior. Secondly, there is statistically significant difference in overall students learning performance with urban areas are higher than rural areas. Finally, it is suggested that in addition to strengthen energy attitudes and energy awareness, we should encourage students to take action in save energy in their daily life. Furthermore, we should invest more resources to rural areas to balance the students’ performances between urban and rural areas

    Game Solving with Online Fine-Tuning

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    Game solving is a similar, yet more difficult task than mastering a game. Solving a game typically means to find the game-theoretic value (outcome given optimal play), and optionally a full strategy to follow in order to achieve that outcome. The AlphaZero algorithm has demonstrated super-human level play, and its powerful policy and value predictions have also served as heuristics in game solving. However, to solve a game and obtain a full strategy, a winning response must be found for all possible moves by the losing player. This includes very poor lines of play from the losing side, for which the AlphaZero self-play process will not encounter. AlphaZero-based heuristics can be highly inaccurate when evaluating these out-of-distribution positions, which occur throughout the entire search. To address this issue, this paper investigates applying online fine-tuning while searching and proposes two methods to learn tailor-designed heuristics for game solving. Our experiments show that using online fine-tuning can solve a series of challenging 7x7 Killall-Go problems, using only 23.54% of computation time compared to the baseline without online fine-tuning. Results suggest that the savings scale with problem size. Our method can further be extended to any tree search algorithm for problem solving. Our code is available at https://rlg.iis.sinica.edu.tw/papers/neurips2023-online-fine-tuning-solver.Comment: Accepted by the 37th Conference on Neural Information Processing Systems (NeurIPS 2023

    Biosynthesis and Biomimetic Synthesis of Flavonoid Diels-Alder Natural Products

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    This chapter describes the biosynthesis and biomimetic synthesis of naturally occurring flavonoid Diels‐Alder adducts found either from the family Moraceae or Zingiberaceae. The main topics addressed are biosynthetic studies by employing Morus alba L. cell cultures through feeding experiments of various exogenous substrates and putative precursors, as well as a various biomimetic approach for the chemical syntheses of flavonoid Diels‐Alder natural products

    A Local-Pattern Related Look-Up Table

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    This paper describes a Relevance-Zone pattern table (RZT) that can be used to replace a traditional transposition table. An RZT stores exact game values for patterns that are discovered during a Relevance-Zone-Based Search (RZS), which is the current state-of-the-art in solving L&D problems in Go. Positions that share the same pattern can reuse the same exact game value in the RZT. The pattern matching scheme for RZTs is implemented using a radix tree, taking into consideration patterns with different shapes. To improve the efficiency of table lookups, we designed a heuristic that prevents redundant lookups. The heuristic can safely skip previously queried patterns for a given position, reducing the overhead to 10% of the original cost. We also analyze the time complexity of the RZT both theoretically and empirically. Experiments show the overhead of traversing the radix tree in practice during lookup remain flat logarithmically in relation to the number of entries stored in the table. Experiments also show that the use of an RZT instead of a traditional transposition table significantly reduces the number of searched nodes on two data sets of 7x7 and 19x19 L&D Go problems.Comment: Submitted to IEEE Transactions on Games (under review

    A STUDY OF THE INFLUENCES OF KNOWLEDGE BOUNDARY SPANNING ON PROJECT PERFORMANCE IN INFORMATION SYSTEM DEVELOPMENT PROJECTS

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    Information system development (ISD) is a knowledge intensive process, and a socialize cross-disciplines collaboration that brings up innovations and creates a competitive advantage for the organization. However, different layers of knowledge boundaries (syntactic, semantic, pragmatic) arise with the knowledge diversity of the ISD project and further lowers the project performance and product quality. To solve the problems, we will follow a construct development methodology to empirically identify the critical knowledge boundary spanning (KBS) processes, roles and objects for different layers of knowledge boundary, examine their influences to the effectiveness of corresponding KBS, and further assess the direct and moderating relationships from KBS effectiveness to project performance and product quality through a questionnaire survey. For academic applications, we not only split up the layers of KBS effectiveness and examine their direct and moderating effects to ISD performance but also offer categorized KBS activities under a formal construct development methodology for future studies. For practical implications, we offer a model for ISD team members to refer to for solving their knowledge boundary issues and increase their project performance and product quality
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