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101.
102.
Model checking of isolated software components is inherently not possible because a component does not form a complete program with an explicit starting point. To overcome this obstacle, it is typically necessary to create an environment of the component which is the intended subject to model checking. We present our approach to automated environment generation that is based on behavior protocols [Plasil, F., and S. Visnovsky, Behavior Protocols for Software Components, IEEE Transactions on Software Engineering, 28(2002)]; to our knowledge, this is the only environment generator designed for model checking of software components. We compare it with the approach taken in the Bandera Environment Generator tool [Tkachuk, O., M. B. Dwyer and C. S. Pasareanu, Automated Environment Generation for Software Model Checking, 18th IEEE International Conference on Automated Software Engineering (ASE03), p. 116, 2003], designed for model checking of sets of Java classes. 相似文献
103.
Zuzana Hejdankova Vaclav Vanek Frantisek Sedlak Jan Prochazka Audrey Diederichs Sami Kereïche Barbora Novotna Milos Budesinsky Gabriel Birkus Klara Grantz Saskova Petr Cigler 《Advanced functional materials》2021,31(47):2101391
Lipid nanoparticles (LNPs) are the most advanced nonviral modality for nucleic acid (NA) delivery, and have recently gained enormous attention in the fields of RNA therapeutics and vaccine development. Here, ionizable adamantane-based lipidoids named XMaNs, which circumvent the usual need for laborious optimization of LNP components for highly diverse types of NAs, are described. The non-toxic XMaN6 lipidoid is highly versatile in entrapment and delivery of siRNA, mRNA, plasmid DNA, and a cyclic dinucleotide. XMaN6-based LNPs efficiently deliver: 1) siRNA into human primary hepatocytes and cell lines that are hard-to-transfect; 2) mRNA into mouse liver; 3) plasmid DNA; 4) 2′,3′-cGAMP into cells and activated the cGAS-STING pathway three orders of magnitude more efficiently than 2′,3′-cGAMP alone. To our knowledge, such universality in delivering different NA types has not been previously described and can accelerate translation of LNPs into the clinic. 相似文献
104.
One of the topics which forms part of CONRAD project addresses the problems related to the dosimetry of complex-mixed radiation fields at workplaces. This topic was included in work package (WP) 6. WP 6 was established to co-ordinate research activities in two areas:the development of new techniques and the improvement of current techniques for characterisation of complex workplace fields (including high-energy fields and pulsed fields): measurement and calculation of particle energy and direction distributions (Subgroup A); and model improvements for dose assessment of solar particle events (Subgroup B). In both cases in order to aid the research, WP 6 increases the efficiency of resource utilisation, and facilitates the technology transfer to practical application and for the development of standards. This contribution presents a general overview of activities of SG A; specific results related to the benchmark experiment at GSI Darmstadt are presented separately, and will be published in other way. As far as the results acquired in the frame of the SG B activities, these are presented in the meeting held as part of EURADOS AM 2008. 相似文献
105.
Plates for thin-layer chromatography (TLC) with an attached layer of porous polymer monolith have been prepared and used for the separation of small molecules, peptides, and proteins. The 50-200-mum. thin poly(butyl methacrylate-co-ethylene dimethacrylate) layers were prepared in situ using UV-initiated polymerization. Precise control of the reaction conditions enables the preparation of monolithic layers with a well-defined porous structure that determines the chromatographic performance. Compared to conventional TLC and high-performance TLC using precoated layers based on silica, the small layer thickness and absence of any binder is expected to improve both retention characteristics and separation efficiency of the polymer-based monolithic thin-layer chromatographic plates. Spots of the separated compounds were first detected using typical UV imaging. Since the monolithic thin layers can be also prepared directly on the stainless steel MALDI carrier plate, the separation in TLC format can be coupled with MALDI-TOF-MS. Application of a conventional MALDI matrix facilitated desorption and ionization of peptides and proteins for molecular weight determination of the separated compounds. 相似文献
106.
The effect of microwave (MW) field on the rate of thermal desorption of polychlorinated biphenyls (PCBs) from long-term contaminated soil was examined in the laboratory environment. For these purposes a modified MW oven was used, with a uniformly extended MW field and a power consumption of 200–600 W. The weight of the soil samples was 100 g, the sum of concentrations of seven indicative congeners of PCB Nos. 28, 52, 101, 118, 153, 138, and 180 was, on average, 264 mg/kg of dry matter. It was experimentally proven that the efficiencies of PCB desorptions were high, over 99.9%. The maximal desorption temperature of 600°C was reached within 15–17 min. It came to light that the presence of alkaline additives in the soil (such as carbonates and alkaline metal hydroxides) did not have an apparent effect on the desorption of PCBs under those conditions. The results concerning the efficiency of PCB separations are in agreement with our previous findings regarding the efficiency of thermal desorption without using MWs in the pilot (input 35 kg) and industrial (input 15 t) desorption chambers with a stationary layer of the same type of contaminated soil. The main disadvantage of experiments with thermal desorption without the action of MWs was the low rate of heating up the soil. This study was focused to solve the problem of contamination in a complex way; we also studied the effect of MWs on the rate of the deterioration of the separated PCBs in aqueous condensates, the deterioration of PCBs in contaminated waste water containing alkaline agents (soda and lye), and on the catalytic reductive dechlorination of PCBs in the system Pd supported on active coal with sodium formate as the hydrogen donor. Experiments with the MW-enhanced catalytic reductive oxidation show over 98.5% reduction in the concentration of PCBs. An important and new finding is the more than 98% reduction in the concentration of PCBs when the MW field was applied on the contaminated water into which only 2.5% of Na2CO3 was added. Further studies on possible influences of MWs on the reaction kinetic are needed. Meanwhile we attribute the positive MW effects to their thermal properties rather than to their influence on the reaction mechanism. 相似文献
107.
Expression,Receptor Binding,and Biophysical Characterization of Guinea Pig Insulin desB30: A Monomeric Insulin Variant
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Ebbe Engholm Dr. Thomas H. Hansen Dr. Eva Johansson Dr. Holger M. Strauss Dr. Tine N. Vinther Prof. Knud J. Jensen Dr. Frantisek Hubálek Dr. Thomas B. Kjeldsen 《Chembiochem : a European journal of chemical biology》2015,16(6):954-958
Here we report, for the first time, the heterologous expression of desB30 guinea pig insulin (GI desB30) in the yeast Saccharomyces cerevisiae. The affinities of GI desB30 for the insulin receptor A and the IGF‐I receptor were also quantified for the first time. Small‐angle X‐ray scattering and analytical ultracentrifugation studies confirmed that GI desB30 did not form dimers or hexamers, in contrast to human insulin. Sizeexclusion chromatography connected to inductively coupled plasma mass spectrometry revealed that GI desB30 has affinity towards several divalent metal ions. These studies did not indicate the formation of any larger structures of GI desB30 in the presence of various divalent metal ions, but did indicate that GI desB30 has an affinity towards Mn, Co, and Cu ions. Finally, the low affinity for the insulin receptor and the very low affinity for the IGF‐I receptor by GI desB30 were quantified. 相似文献
108.
Temperature analysis of steel structures protected by intumescent paint with steel claddings in fire
It is of great interest to understand the stabilization effect of steel structures by steel claddings in fire. Structural fire analysis using finite-element method, including temperature analysis and structural analysis, is important to investigate the stabilization effect. However, temperature-dependent thermal material data for the insulation layer of sandwich panels and the intumescent paint for fire protection of steel sections are still scarce. In this paper, the available thermal properties of these materials from the literature are summarized, and 2D and 3D temperature analyses were carried out for steel sections with steel claddings, such as sandwich panels with mineral wool and polyisocyanurate (PIR) cores and trapezoidal sheeting with mineral wool insulation. The analysis results were compared with the fire tests conducted in European research project STABFI (Stabilization of Steel Structures by Steel Claddings in Fire). The study shows reasonable accuracy of modeling using existing thermal material data for temperature-dependent insulation properties and thermal data for intumescent paint, for intumescent coatings (IC) protected steel beam with mineral wool sandwich panel and trapezoidal sheeting claddings. Larger discrepancy between finite element (FE) prediction and test measurement was observed for the case of sandwich cladding with PIR core. Gaps for further research were identified. The study also shows the heat sink effect of the steel section by sandwich panels with a mineral wool core. Therefore, it is recommended that the sandwich panels should be included in the thermal analysis model for steel sections with sandwich claddings. 相似文献
109.
Kaipeng Cheng Frantisek Svec Yongqin Lv Tianwei Tan 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(44)
Encapsulation of enzymes in metal–organic frameworks (MOFs) is often obstructed by the small size of the orifices typical of most reported MOFs, which prevent the passage of larger‐size enzymes. Here, the preparation of hierarchical micro‐ and mesoporous Zn‐based MOFs via the templated emulsification method using hydrogels as a template is presented. Zinc‐based hydrogels featuring a 3D interconnecting network are first produced via the formation of hydrogen bonds between melamine and salicylic acid in which zinc ions are well distributed. Further coordination with organic linkers followed by the removal of the hydrogel template produces hierarchical Zn‐based MOFs containing both micropores and mesopores. These new MOFs are used for the encapsulation of glucose oxidase and horseradish peroxidase to prove the concept. The immobilized enzymes exhibit a remarkably enhanced increased operational stability and enzymatic activity with a kcat/km value of 85.68 mm s–1. This value is 7.7‐fold higher compared to that found for the free enzymes in solution, and 2.7‐fold higher than enzymes adsorbed on conventional microporous MOFs. The much higher catalytic activity of the mesoporous conjugate for Knoevenagel reactions is demonstrated, since the large pores enable easier access to the active sites, and compared with that observed for catalysis using microporous MOFs. 相似文献
110.
Monolithic poly(glycidyl methacrylate-co-ethylene dimethacrylate) and poly(butyl methacrylate-co-ethylene dimethacrylate) capillary columns, which incorporate the new monomer [6,6]-phenyl-C(61)-butyric acid 2-hydroxyethyl methacrylate ester, have been prepared and their chromatographic performance have been tested for the separation of small molecules in the reversed phase. While addition of the C60-fullerene monomer to the glycidyl methacrylate-based monolith enhanced column efficiency 18-fold, to 85,000 plates/m at a linear velocity of 0.46 mm/s and a retention factor of 2.6, when compared to the parent monolith, the use of butyl methacrylate together with the carbon nanostructured monomer afforded monolithic columns with an efficiency for benzene exceeding 110,000 plates/m at a linear velocity of 0.32 mm/s and a retention factor of 4.2. This high efficiency is unprecedented for separations using porous polymer monoliths operating in an isocratic mode. Optimization of the chromatographic parameters affords near baseline separation of 6 alkylbenzenes in 3 min with an efficiency of 64,000 plates/m. The presence of 1 wt % or more of water in the polymerization mixture has a large effect on both the formation and reproducibility of the monoliths. Other factors such as nitrogen exposure, polymerization conditions, capillary filling method, and sonication parameters were all found to be important in producing highly efficient and reproducible monoliths. 相似文献