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991.
Lanthanide metal organic frameworks (MOFs), Eu(BTC) and TbEu(BTC) were assessed to follow uptake of deoxynucleotide triphosphate (dNTPs) in loop mediated isothermal amplification (LAMP) using BST2.0. dNTPs could be determined below 150 μM. A ratiometic measurement of Tb3+:Eu3+ fluorescence in TbEu(BTC) gave a limit of detection of 2.08 μM for dNTPs. dNTP uptake slowed above 8 mM Mg2+. This correlated with end-point and real-time LAMP, using PicoGreen and SYBR green respectively. For the P.Mal-Lau 18S rRNA primer set, with P. malariae a detection limit of 102.5 copies was obtained. Cross reactivity between P. malariae and P. knowlesi was shown with 18S rRNA primer sets. 相似文献
992.
Ng Wei Wuen Thiam Hui San Pang Yean Ling Lim Yun Seng Wong Jianhui 《Journal of Solid State Electrochemistry》2023,27(6):1477-1492
Journal of Solid State Electrochemistry - Getting the direct methanol fuel cell (DMFC) closer to mass production requires the creation of a high-performance and long-lasting proton exchange... 相似文献
993.
Paul Varava Tak Hin Wong Zhaowen Dong Anastasia Yu. Gitlina Andrzej Sienkiewicz Wolfram Feuerstein Rosario Scopelliti Farzaneh Fadaei-Tirani Kay Severin 《Angewandte Chemie (International ed. in English)》2023,62(25):e202303375
The head-to-tail dimerization of N-heterocyclic diazoolefins is described. The products of these formal (3+3) cycloaddition reactions are strongly reducing quinoidal tetrazines. Oxidation of the tetrazines occurs in a stepwise fashion, and we were able to isolate a stable radical cation and diamagnetic dications. The latter are also accessible by oxidative dimerization of diazoolefins. 相似文献
994.
Dr. Amit Kumar Simlandy Turki M. Alturaifi Dr. Johny M. Nguyen Dr. Lucas J. Oxtoby Quynh Nguyen Wong Dr. Jason S. Chen Prof. Peng Liu Prof. Keary M. Engle 《Angewandte Chemie (International ed. in English)》2023,62(29):e202304013
The catalytic enantioselective synthesis of α-chiral alkenes and alkynes represents a powerful strategy for rapid generation of molecular complexity. Herein, we report a transient directing group (TDG) strategy to facilitate site-selective palladium-catalyzed reductive Heck-type hydroalkenylation and hydroalkynylation of alkenylaldehyes using alkenyl and alkynyl bromides, respectively, allowing for construction of a stereocenter at the δ-position with respect to the aldehyde. Computational studies reveal the dual beneficial roles of rigid TDGs, such as L-tert-leucine, in promoting TDG binding and inducing high levels of enantioselectivity in alkene insertion with a variety of migrating groups. 相似文献
995.
Side-Chain Chemistry Governs Hierarchical Order of Charge-Complementary β-sheet Peptide Coassemblies
Dr. Renjie Liu Xin Dong Dr. Dillon T. Seroski Dr. Bethsymarie Soto Morales Dr. Kong M. Wong Alicia S. Robang Lucas Melgar Prof. Thomas E. Angelini Prof. Anant K. Paravastu Prof. Carol K. Hall Prof. Gregory A. Hudalla 《Angewandte Chemie (International ed. in English)》2023,62(51):e202314531
Self-assembly of proteinaceous biomolecules into functional materials with ordered structures that span length scales is common in nature yet remains a challenge with designer peptides under ambient conditions. This report demonstrates how charged side-chain chemistry affects the hierarchical co-assembly of a family of charge-complementary β-sheet-forming peptide pairs known as CATCH(X+/Y−) at physiologic pH and ionic strength in water. In a concentration-dependent manner, the CATCH(6K+) (Ac-KQKFKFKFKQK-Am) and CATCH(6D−) (Ac-DQDFDFDFDQD-Am) pair formed either β-sheet-rich microspheres or β-sheet-rich gels with a micron-scale plate-like morphology, which were not observed with other CATCH(X+/Y−) pairs. This hierarchical order was disrupted by replacing D with E, which increased fibril twisting. Replacing K with R, or mutating the N- and C-terminal amino acids in CATCH(6K+) and CATCH(6D−) to Qs, increased observed co-assembly kinetics, which also disrupted hierarchical order. Due to the ambient assembly conditions, active CATCH(6K+)-green fluorescent protein fusions could be incorporated into the β-sheet plates and microspheres formed by the CATCH(6K+/6D−) pair, demonstrating the potential to endow functionality. 相似文献
996.
997.
We consider the following boundary value problem (-1)ny(2n)=F(t,y), n≥ 1, t ∈ (0,1), y(2i)(0)=y(2i)(1)=0, 0≧i≧n-1. Criteria are developed for the existence of two and three positive solutions of the boundary value problem. In addition, for special cases we establish upper and lower bounds for these positive solutions. Several examples are also included to dwell upon the importance of the results obtained. 相似文献
998.
Lawrence C. Leung Yer Van Hui Gang Chen Wai Hung Wong 《The Journal of the Operational Research Society》2017,68(6):695-710
Resource planning of airfreight forwarders is a complex endeavor, requiring decisions to be made in a dynamic and uncertain environment. Airfreight forwarders acquire airfreight spaces from three sources: allotment from carriers, retail from carriers and subcontracting to partners, all of which differ in terms of cost, flexibility and timing of booking. This real-life problem has many planning decisions (bookings in terms of carriers, route, time, ULDs, etc.). In this case study, we propose an aggregate–disaggregate approach and focus on the most critical decisions. A two-stage stochastic dynamic program first determines, in aggregates, the amount of allotment bookings, retail resources, and subcontracting or surplus co-loading. Then, a heuristic is used to disaggregate resource requirements into specific bookings. An analysis is provided to examine the relevant managerial issues. Based on real-life data, we show several patterns of aggregate resource bookings with respect to different levels of demand uncertainty and cost parameters. We show that resource disaggregation has to balance cost-effectiveness, capacity flexibility and routing flexibility of a resource plan. 相似文献
999.
1000.
In this note we shall give characterisations for HNN extensions of non-cyclic polycyclic-by-finite groups with normal infinite cyclic associated subgroups to be residually finite, subgroup separable and conjugacy separable. 相似文献