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21.
ALBERTAS ČAPLINSKAS 《Journal of Intelligent Manufacturing》1998,9(6):493-502
The aim of this paper is comparative analysis of most important AI paradigms. An AI paradigm is defined as the pair composed by a concept of intelligence and a methodology in which intelligent computer systems are developed and operated. Three paradigms, the behaviourist paradigm, the agent paradigm, and the artificial life paradigm are discussed. 相似文献
22.
Dr. Armin Welker Dr. Christian Kersten Dr. Christin Müller Dr. Ramakanth Madhugiri Collin Zimmer Patrick Müller Robert Zimmermann Stefan Hammerschmidt Hannah Maus Prof. John Ziebuhr Prof. Christoph Sotriffer Prof. Tanja Schirmeister 《ChemMedChem》2021,16(2):340-354
Inhibition of coronavirus (CoV)-encoded papain-like cysteine proteases (PLpro) represents an attractive strategy to treat infections by these important human pathogens. Herein we report on structure-activity relationships (SAR) of the noncovalent active-site directed inhibitor (R)-5-amino-2-methyl-N-(1-(naphthalen-1-yl)ethyl) benzamide ( 2 b ), which is known to bind into the S3 and S4 pockets of the SARS-CoV PLpro. Moreover, we report the discovery of isoindolines as a new class of potent PLpro inhibitors. The studies also provide a deeper understanding of the binding modes of this inhibitor class. Importantly, the inhibitors were also confirmed to inhibit SARS-CoV-2 replication in cell culture suggesting that, due to the high structural similarities of the target proteases, inhibitors identified against SARS-CoV PLpro are valuable starting points for the development of new pan-coronaviral inhibitors. 相似文献
23.
Serena Montalbano Francesca Degola Jennifer Bartoli Franco Bisceglie Annamaria Buschini Mauro Carcelli Donatella Feretti Serena Galati Laura Marchi Nicol Orsoni Giorgio Pelosi Marianna Pioli Francesco M. Restivo Dominga Rogolino Mirco Scaccaglia Olga Serra Giorgio Spadola Gaia C. V. Viola Ilaria Zerbini Claudia Zani 《International journal of molecular sciences》2021,22(9)
The control of the fungal contamination on crops is considered a priority by the sanitary authorities of an increasing number of countries, and this is also due to the fact that the geographic areas interested in mycotoxin outbreaks are widening. Among the different pre- and post-harvest strategies that may be applied to prevent fungal and/or aflatoxin contamination, fungicides still play a prominent role; however, despite of countless efforts, to date the problem of food and feed contamination remains unsolved, since the essential factors that affect aflatoxins production are various and hardly to handle as a whole. In this scenario, the exploitation of bioactive natural sources to obtain new agents presenting novel mechanisms of action may represent a successful strategy to minimize, at the same time, aflatoxin contamination and the use of toxic pesticides. The Aflatox® Project was aimed at the development of new-generation inhibitors of aflatoxigenic Aspergillus spp. proliferation and toxin production, through the modification of naturally occurring molecules: a panel of 177 compounds, belonging to the thiosemicarbazones class, have been synthesized and screened for their antifungal and anti-aflatoxigenic potential. The most effective compounds, selected as the best candidates as aflatoxin containment agents, were also evaluated in terms of cytotoxicity, genotoxicity and epi-genotoxicity to exclude potential harmful effect on the human health, the plants on which fungi grow and the whole ecosystem. 相似文献
24.
Shi-Cheng Tong Teck-Kim Tang Yee-Ying Lee 《European Journal of Lipid Science and Technology》2021,123(12):2100132
Fractionation is a well-established process adopted in the fats and oils industries. It involves the separation of low and high melting triacylglycerol under controlled cooling conditions into olein and stearin fractions with distinct chemical and physical properties. Amongst the other vegetable oils, palm oil is one of the most fractionated oils in the past few decades mainly attributed to its semisolid properties. The various fraction of palm oil allows it to be used in different types of food products such as margarine, frying oil, and cocoa butter substitute. In fractionation, proper control of the fractionation conditions is important to produce the fractions with desirable stearin and olein quality. The purpose of this paper is to critically review the fractionation conditions (crystallization temperature, agitation, cooling rate and crystallization time) that affect the yield and quality of the oil produced. Additionally, it also provides the latest updates on the influence of seeding agents (diacylglycerol, monoacylglycerol, hard fat, phytosterol, phospholipid, lecithin, essential oil, sugar, polyglycerol ester, and talc) used in fractionation. This article is useful to provide a fundamental understanding of fractionation to scientists from the industries or academia working in the fats and oils industries. Practical Applications: This paper provides an in-depth understanding of fractionation particularly on the parameters of fractionation in influencing the quality and yield of the stearin and olein produced. It also for the first time presents the effect of addition of various seeding agents on palm oil fractionation which can help the industry to select the appropriate seeding agents to improve the currently employed fractionation process. Thus, it can act as a guideline for the industry to understand and select the appropriate fractionation conditions when developing a new product using this approach. The fractionation conditions discussed here can also be used as a reference when fractionating other types of fats and oils as most of them share a common background. 相似文献
25.
Dr. Xicheng Liu Mingxiao Shao Congcong Liang Jinghang Guo Guangxuan Wang Xiang-Ai Yuan Zhihong Jing Laijin Tian Prof. Dr. Zhe Liu 《Chembiochem : a European journal of chemical biology》2021,22(3):557-564
A series of half-sandwich structural iridium(III) phenanthroline (Phen) complexes with halide ions (Cl−, Br−, I−) and pyridine leaving groups ([(η5-CpX)Ir(Phen)Z](PF6)n, Cpx: electron-rich cyclopentadienyl group, Z: leaving group) have been prepared. Target complexes, especially the Cpxbiph (biphenyl-substituted cyclopentadienyl)-based one, showed favourable anticancer activity against human lung cancer (A549) cells; the best one ( Ir8 ) was almost five times that of cisplatin under the same conditions. Compared with complexes involving halide ion leaving groups, the pyridine-based one did not display hydrolysis but effectively caused lysosomal damage, leading to accumulation in the cytosol, inducing an increase in the level of intracellular reactive oxygen species and apoptosis; this indicated an anticancer mechanism of oxidation. Additionally, these complexes could bind to serum albumin through a static quenching mechanism. The data highlight the potential value of half-sandwich iridium(III) phenanthroline complexes as anticancer drugs. 相似文献
26.
Alexander Zimmermann Qais Z. Jaber Dr. Johannes Koch Steffen Riebe Dr. Cecilia Vallet Dr. Kateryna Loza Matthias Hayduk Dr. Kfir B. Steinbuch Prof. Shirley K. Knauer Prof. Micha Fridman Jun.-Prof. Jens Voskuhl 《Chembiochem : a European journal of chemical biology》2021,22(9):1563-1567
We report the characterization of amphiphilic aminoglycoside conjugates containing luminophores with aggregation-induced emission properties as transfection reagents. These inherently luminescent transfection vectors are capable of binding plasmid DNA through electrostatic interactions; this binding results in an emission “on” signal due to restriction of intramolecular motion of the luminophore core. The luminescent cationic amphiphiles effectively transferred plasmid DNA into mammalian cells (HeLa, HEK 293T), as proven by expression of a red fluorescent protein marker. The morphologies of the aggregates were investigated by microscopy as well as ζ-potential and dynamic light-scattering measurements. The transfection efficiencies using luminescent cationic amphiphiles were similar to that of the gold-standard transfection reagent Lipofectamine® 2000. 相似文献
27.
Johannes Karges Seth M. Cohen 《Chembiochem : a European journal of chemical biology》2021,22(16):2600-2607
The severe acute respiratory syndrome – coronavirus 2 (SARS-CoV-2), the infectious agent responsible for COVID-19 – has caused more than 2.5 million deaths worldwide and triggered a global pandemic. Even with successful vaccines being delivered, there is an urgent need for novel treatments to combat SARS-CoV-2, and other emerging viral diseases. While several organic small molecule drug candidates are in development, some effort has also been devoted towards the application of metal complexes as potential antiviral agents against SARS-CoV-2. Herein, the metal complexes that have been reported to show antiviral activity against SARS-CoV-2 or one of its target proteins are described and their proposed mechanisms of action are discussed. 相似文献
28.
29.
化学镀Ni-Cu-P添加剂的研究 总被引:5,自引:0,他引:5
通过对化学镀Ni-Cu-P合金的稳定剂、表面活性剂、光亮剂对镀层性能及镀液稳定性的影响研究,得出最佳实验配方。 相似文献
30.
我国木质素油田化学品的发展现状 总被引:7,自引:0,他引:7
马宝岐 《纤维素科学与技术》1994,(Z1)
本文综述了我国木质素类(碱木质素或木质素磺酸盐)油田化学品的最新进展,其中包括钻井液处理剂、油井水泥添加剂、堵水剂、调剖剂、稠油降粘剂和表面活性剂驱油的牺牲剂。目前我国木质素类堵水剂、调剖剂和稠油降粘剂的研究和应用方面已达到或超过世界先进水平,改性木质素磺酸盐的研究也接近国际先进水平,但钻井处理剂和水泥添加剂仅为美国的1/9,许多木质素化学品仍为空白。因此,这些油田化学品仍然是吸引人去研究的课题,期望不久的将来会有较大的进展。 相似文献