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971.
The insignificant relationship between rewards and actual compliance with information security policies does not make sense. Quite possibly this relationship results from not applying rewards for security compliance. 相似文献
972.
Roksana Markiewicz Adam Klimaszyk Marcin Jarek Micha Taube Patryk Florczak Marek Kempka Zbigniew Fojud Stefan Jurga 《International journal of molecular sciences》2021,22(11)
The application of ionic liquids (ILs) has grown enormously, from their use as simple solvents, catalysts, media in separation science, or electrolytes to that as task-specific, tunable molecular machines with appropriate properties. A thorough understanding of these properties and structure–property relationships is needed to fully exploit their potential, open new directions in IL-based research and, finally, properly implement the appropriate applications. In this work, we investigated the structure–properties relationships of a series of alkyltriethylammonium bis(trifluoromethanesulfonyl)imide [TEA-R][TFSI] ionic liquids in relation to their thermal behavior, structure organization, and self-diffusion coefficients in the bulk state using DSC, FT-IR, SAXS, and NMR diffusometry techniques. The phase transition temperatures were determined, indicating alkyl chain dependency. Fourier-transformed infrared spectroscopy studies revealed the structuration of the ionic liquids along with alkyl chain elongation. SAXS experiments clearly demonstrated the existence of polar/non-polar domains. The alkyl chain length influenced the expansion of the non-polar domains, leading to the expansion between cation heads in polar regions of the structured IL. 1H NMR self-diffusion coefficients indicated that alkyl chain elongation generally caused the lowering of the self-diffusion coefficients. Moreover, we show that the diffusion of anions and cations of ILs is similar, even though they vary in their size. 相似文献
973.
Jaromir Gumulec Michaela Fojtu Martina Raudenska Marketa Sztalmachova Anna Skotakova Jana Vlachova Sylvie Skalickova Lukas Nejdl Pavel Kopel Lucia Knopfova Vojtech Adam Rene Kizek Marie Stiborova Petr Babula Michal Masarik 《International journal of molecular sciences》2014,15(12):22960-22977
Doxorubicin is an effective chemotherapeutic drug, however, its toxicity is a significant limitation in therapy. Encapsulation of doxorubicin inside liposomes or ferritin cages decreases cardiotoxicity while maintaining anticancer potency. We synthesized novel apoferritin- and liposome-encapsulated forms of doxorubicin (“Apodox” and “lip-8-dox”) and compared its toxicity with doxorubicin and Myocet on prostate cell lines. Three different prostatic cell lines PNT1A, 22Rv1, and LNCaP were chosen. The toxicity of the modified doxorubicin forms was compared to conventional doxorubicin using the MTT assay, real-time cell impedance-based cell growth method (RTCA), and flow cytometry. The efficiency of doxorubicin entrapment was 56% in apoferritin cages and 42% in the liposome carrier. The accuracy of the RTCA system was verified by flow-cytometric analysis of cell viability. The doxorubicin half maximal inhibition concentrations (IC50) were determined as 170.5, 234.0, and 169.0 nM for PNT1A, 22Rv1, and LNCaP, respectively by RTCA. Lip8-dox is less toxic on the non-tumor cell line PNT1A compared to doxorubicin, while still maintaining the toxicity to tumorous cell lines similar to doxorubicin or epirubicin (IC50 = 2076.7 nM for PNT1A vs. 935.3 and 729.0 nM for 22Rv1 and LNCaP). Apodox IC50 was determined as follows: 603.1, 1344.2, and 931.2 nM for PNT1A, 22Rv1, and LNCaP. 相似文献
974.
The majority of important reactions in beer are associated with the action of oxygen during malting and brewing. With respect to oxygen, beer is considered to possess a relatively strong reducing environment. The gradual reduction of oxygen gives rise to reactive oxygen species (ROS) capable of attacking beer components that are important to consumers. Indigo carmine (IC) bleaching was used to prove ROS formation formed by oxidation of beer energy sources such as maltose and ethanol. This paper examines oxygen radical oxidation of organic matter in the presence of the radical initiator potassium peroxodisulphate. A mixture of organic sources of energy such as maltose and ethanol, oxygen, radical initiator and cupric ions generates ROS formation in a broad range of concentrations even at room temperature. ROS irreversibly split blue dye IC into the colourless form and takes part in the radical transformation of organic matter, which is similar to its burning at low temperature or to radical oxidation of reducing agents. Other organic matter can suppress ROS formation and be incorporated into the radical chain of the pathway of its ‘cold burning’. Ethanol inhibited phenylalanine oxidation during its oxidative Maillard reaction. IC bleaching can serve as simple indicator of ROS generation in aerated food. Copyright © 2015 The Institute of Brewing & Distilling 相似文献
975.
We show here how a simple data mining of bibliographic records can be used to follow and help understand the evolution of a research domain, at a level that cannot be captured by reading individual papers in a field of this size. We illustrate the approach by investigating 43 yr of research on ceramic materials, covered by 253 000 bibliographic records. The patterns of keywords used reveal the trends and the evolution of research ideas and priorities within the field. Simple, interactive tools based on co‐word network analysis help us better appreciate the organization and relationships of ideas or individuals, and hopefully allow identification of unexplored concepts, connections, or approaches on a given topic. 相似文献
976.
Recycling of lignocellulosics filled polypropylene composites. I. Analysis of thermal properties,morphology, and amount of free radicals 下载免费PDF全文
Dominik Paukszta Ewa Markiewicz Adam Ostrowski Beata Doczekalska Magdalena Brzyska Marek Szostak Sławomir Borysiak 《应用聚合物科学杂志》2015,132(12)
Composites of isotactic polypropylene filled with comminuted rapeseed straw are studied. Improvement in interfacial adhesion is achieved by chemical modification of the lignocellulose filler. Composites were subjected to recycling by extrusion. The effect of multiple recycling of the composites on the process of nucleation and crystallization of polypropylene matrix, surface topography, and free radical generation was checked. On the basis of differential scanning calorimetry data, a significant influence of the recycling on nucleation activity of the lignocellulose filler was evidenced. A relation between the filler particle size and multiple recycling was established by observations under a polarization microscope, while scanning electron microscope analyses confirmed the positive effect of chemical modification of rapeseed straw on the interfacial adhesion. The composite structure changes forced by multiple recycling are discussed in the context of free radical generation. Concentration of free radicals in the rapeseed straw samples and composites was measured by the electron paramagnetic resonance spectroscopy to show that it was higher in the systems subjected to multiple recycling. Interestingly, the composites after multiple recycling showing elevated concentration of free radicals are also characterized by higher nucleation activity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41693. 相似文献
977.
Cécile Santos Frédéric Rogriguez Virginie Garcia Daniela Moravčíková Dr. Dušan Berkeš Prof. Adam Daïch Prof. Thierry Levade Dr. Cécile Baudoin‐Dehoux Dr. Stéphanie Ballereau Dr. Yves Génisson 《Chembiochem : a European journal of chemical biology》2014,15(17):2522-2528
A highly compartmentalized enzymatic network regulates the pro‐apoptotic and proliferative effects of sphingolipids. Over‐conversion of ceramide (Cer) correlates with insensitivity to apoptosis signaling (in response to chemotherapy) and to drug resistance of cancer cells. De novo sphingomyelin biosynthesis relies on non‐vesicular ceramide trafficking by the CERT (CERamide Transfer) protein. Therefore, blocking CERT transfer, thus leading to increased intracellular ceramide availability, represents a potential anticancer strategy. Our study is based on the implementation of an in vitro binding assay, supported by in silico molecular docking. It constitutes the first attempt to explore at the molecular level for the identification of novel CERT ligands. This approach is the first step toward in silico design and optimization of CERT inhibitor candidates, potentially relevant as innovative ceramide‐transfer‐targeting therapeutic agents. 相似文献
978.
The Discovery of Potent Nonstructural Protein 5A (NS5A) Inhibitors with a Unique Resistance Profile—Part 2 下载免费PDF全文
Florian Wakenhut Thien Duc Tran Dr. Chris Pickford Stephen Shaw Dr. Mike Westby Caroline Smith‐Burchnell Lesa Watson Michael Paradowski Dr. Jared Milbank David Stonehouse Dr. Kathy Cheung Dr. Robert Wybrow Dr. Felice Daverio Dr. Samuel Crook Keith Statham Dr. David Leese Dr. Darren Stead Fiona Adam Duncan Hay Dr. Lee R. Roberts Jean‐Yves Chiva Carly Nichols Dr. David C. Blakemore Gilles H. Goetz Dr. Ye Che Iain Gardner Satish Dayal Dr. Andrew Pike Rob Webster Dr. David C. Pryde 《ChemMedChem》2014,9(7):1387-1396
In ongoing studies towards novel hepatitis C virus (HCV) therapeutics, inhibitors of nonstructural protein 5A (NS5A) were evaluated. Specifically, starting from previously reported lead compounds, peripheral substitution patterns of a series of biaryl‐linked pyrrolidine NS5A replication complex inhibitors were probed and structure–activity relationships were elucidated. Using molecular modelling and a supercritical fluid chromatographic (SFC) technique, intramolecular H‐bonding and peripheral functional group topology were evaluated as key determinants of activity and membrane permeability. The novel compounds exhibited retained potency as compared with the lead compounds, and also showed promising results against a panel of resistance viruses. Together, the results of the study take us a step closer towards understanding the potency of daclatasvir, a clinical candidate upon which the compounds were based, and to designing improved analogues as second‐generation antiviral agents targeting NS5A. 相似文献
979.
Orosco Adam 《精细化工原料及中间体》2014,(4)
正本发明涉及到操作蒸馏塔分离乙醇混合物的过程,乙醇混合物含有乙醇和醋酸,该过程回收的乙醇含醋酸量小于700wppm。蒸馏塔的操作条件可以根据加料组分变化。具体说,过程提供了具有低醋酸浓 相似文献
980.
In the batch emulsion copolymerization of styrene and α-tert-butoxy-ω-vinylbenzyl-polyglycidol macromonomer, carried out at macromonomer concentrations exceeding the critical micelle concentration (cmc), particles are formed by a two-step coagulative nucleation mechanism. This mechanism leaves its mark on morphology of particle interface, rate of polymerization and on molecular weight distribution of the obtained polymer. AFM studies revealed that the interface of particles is composed of objects with dimensions close to dimensions of the primary particles. Compartmentalization of styrene in the macromonomer micelles leads to the higher initial rate of styrene conversion than in the similar macromonomer free homopolymerization of styrene. The initial polymerization in the monomer-swollen macromonomer micelles, similar to the microemulsion polymerization, is responsible for the formation of the highest molecular weight component. In the mature particles there are two different polymerization loci: the interfacial layer and the core. This leads to bimodal molecular weight distribution of the formed polymer. 相似文献