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Imen Boukhris Zied Elouedi Salem Benferhat 《International Journal of Approximate Reasoning》2013,54(8):978-999
Graphical models are efficient and simple ways to represent dependencies between variables. We introduce in this paper the so-called belief causal networks where dependencies are uncertain causal links and where the uncertainty is represented by belief masses. Through these networks, we propose to represent the results of passively observing the spontaneous behavior of the system and also evaluate the effects of external actions. Interventions are very useful for representing causal relations, we propose to compute their effects using a generalization of the “do” operator. Even if the belief chain rule is different from the Bayesian chain rule, we show that the joint distributions of the altered structures to graphically describe interventions are equivalent. This paper also addresses new issues that are arisen when handling interventions: we argue that in real world applications, external manipulations may be imprecise and show that they have a natural encoding under the belief function framework. 相似文献
74.
Jan Bouwe van den Berg Hala Elrofai Josephus Hulshof 《Combustion Theory and Modelling》2013,17(1):1-21
We study a combustion-radiation model which models premixed flames propagating in a gaseous mixture with inert dust. This model combines diffusion of mass and temperature with reaction at the flame front. We choose a free boundary model to describe the propagating flames and take a linearized approximation to model the radiation, but we keep a nonlinear reaction term which is temperature dependent. The radiative transfer of thermal energy emitted and absorbed by dust is modelled using the Eddington equation. We analyse the bifurcation diagram of the travelling wave solution curve. In a specific parameter plane, travelling waves are given by a single smooth curve which is parameterized by the flame temperature. 相似文献
75.
Vikash Kumar Viraj G. Naik Avijit Das Sourayan Basu Bal Malabika Biswas Nupur Kumar Anasuya Ganguly Amrita Chatterjee Mainak Banerjee 《Tetrahedron》2019,75(27):3722-3732
Available online Development of water soluble AIE-active “light-up” bioprobes for the detection of biomacromolecules has drawn huge research interests in recent past. In this study, a series of ethylene glycol modified water soluble tetrameric tetraphenylethylene amphiphiles with pyridinium polar heads (TPE-xEG-Py, x = 3, 4, 6 or 1a-c) have been synthesized by varying the ethylene glycol spacer. Their unique structure allows them to form vesicles and other nanoaggregates in aqueous solutions. These amphiphiles were successfully utilized for fluorimetric detection and quantitation of BSA and DNA based on the electrostatic interactions to trigger AIE-emission from the TPE moiety. The electrostatic interaction was also proved very effective in wash-free imaging of both Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria with up to 92 folds increase in fluorescence response within bacterial concentration 0–12 × 108 CFU mL?1. The strategy is advantageous due to cost-effective and easy synthesis, high water solubility, and fast response. 相似文献
76.
Travelling wave-like solutions of the Zakharov-Kuznetsov equation with variable coefficients are studied using the solutions
of Raccati equation. The solitary wave-like solution, the trigonometric periodic wave solution and the rational wave solution
are obtained with a constraint between coefficients. The property of the solutions is numerically investigated. It is shown
that the coefficients of the equation do not change the wave amplitude, but may change the wave velocity.
相似文献
77.
Dr. Hirokazu Tsukamoto Saki Nakamura Akito Tomida Prof. Dr. Takayuki Doi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(55):12528-12532
Haouamines A, B, and their derivatives were synthesized via Suzuki–Miyaura coupling and three key cyclization reactions as follows: the newly developed palladium(0)-catalyzed arylative cyclization of phenylalanine-derived alkyne–aldehydes with 2-bromoarylboronic acid (an “anti-Wacker”-type cyclization); BF3 ⋅ OEt2-promoted Friedel–Crafts-type cyclization of symmetrical electron-rich aromatic rings adjacent to a tertiary allylic alcohol leading to the indeno-tetrahydropyridine skeleton; and (cyanomethyl)trimethylphosphonium iodide-mediated macrocyclization of amino alcohols to afford aza-paracyclophane precursors. The palladium-catalyzed reduction of mono- and di-triflate intermediates in the later stages enabled the alteration of both the position and number of hydroxyl groups on the C-ring. The instability of haouamine B was dramatically improved by salt formation with formic acid. An unambiguous evaluation of the cytotoxicity of the prepared haouamine derivative formates with and without hydroxyl groups at different positions on the C-ring indicated that the catechol structure in haouamine B produced weak cytotoxicity. 相似文献
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Shuang Qiu Wannan Li Tao Deng Angzhi Bi Yang Yang Xi Jiang Dr. Jie P. Li 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303014
Intercellular proximity labeling has emerged as a promising approach to enable the study of cell-cell interactions (CCIs), but the efficiency of current platforms is limited. Here, we use Ru(bpy)32+ to construct an efficient photocatalytic proximity labeling (PPL) system on the cell surface that allows the highly discriminative CCI detection with spatiotemporal resolution. Through the mechanism study and quantitative characterization on living cells, we demonstrate that the singlet-oxygen (1O2) mechanism is more efficient and specific than the single electron transfer (SET) mechanism in Ru-mediated PPL. Ru(bpy)32+ catalysts with different cell-anchoring moieties are prepared to facilitate the catalyst loading on primary cells. Finally, based on this system, we develop a “live” T cell receptor (TCR) multimer with TCR-T cells that could sensitively identify and discriminate cells presenting antigens of different affinity, providing a powerful tool to better understand the heterogeneity of antigen presenting cells. 相似文献