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141.
MRPC is an RPC system that is designed and optimized for MPMD parallel computing. Existing systems based on standard RPC incur an unnecessarily high cost when used on high‐performance multi‐computers, limiting the appeal of RPC‐based languages in the parallel computing community. MRPC combines the efficient control and data transfer provided by Active Messages (AM) with a minimal multithreaded runtime system that extends AM with the features required to support MPMD. This approach introduces only the necessary RPC overheads for an MPMD environment. MRPC has been integrated into Compositional C++ (CC++), a parallel extension of C++ that offers an MPMD programming model. Basic performance in MRPC is within a factor of two from those of Split‐C, a highly tuned SPMD language, and other messaging layers. CC++ applications perform within a factor of two to six from comparable Split‐C versions, which represent an order of magnitude improvement over previous CC++ implementations. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
142.
Robert Bicki Katarzyna Antoniak-Jurak Kamila Michalska Ewelina Franczyk Marcin Konkol Paweł Kowalik Monika Pańczyk Janusz Ryczkowski Grzegorz Słowik Tadeusz Borowiecki 《International Journal of Hydrogen Energy》2021,46(21):11664-11676
Ni/La–Al2O3 and Ni/Ce–Al2O3 catalysts with a small amount of promoters intended for prereforming of LNG were characterized by XRF, N2 adsorption-desorption, XRD, H2 chemisorption, HRTEM and XPS. The catalytic activity was evaluated in methane steam reforming both in the kinetic and diffusion regime, at temperatures characteristic of pre-reforming. Carbonaceous deposit was analysed by TPO-MS method. The nature and location of the coke were studied by HRTEM.La or Ce addition into Ni–Al system causes the increase of the active surface area of Ni by enhancing its dispersion. Studies at kinetic regime have shown that the promoted catalysts have almost twice the activity than reference Ni–Al catalyst. This effect was not confirmed by measurements in the diffusion regime on whole catalyst tablets. Almost identical textural properties of catalysts and diffusive limitations related to them but not the catalytic properties of the material itself appeared to be crucial factors. The presence of La (but not Ce) causes a significant increase in resistance to coking. 相似文献
143.
144.
Beata Dbrowska-Bouta Grzegorz Sulkowski Mikoaj Saek Magorzata Frontczak-Baniewicz Lidia Struyska 《International journal of molecular sciences》2021,22(6)
Silver nanoparticles (AgNPs) are the one of the most extensively used nanomaterials. The strong antimicrobial properties of AgNPs have led to their use in a wide range of medical and consumer products. Although the neurotoxicity of AgNPs has been confirmed, the molecular mechanisms have not been extensively studied, particularly in immature organisms. Based on information gained from previous in vitro studies, in the present work, we examine whether ionotropic NMDA glutamate receptors contribute to AgNP-induced neurotoxicity in an animal model of exposure. In brains of immature rats subjected to a low dose of AgNPs, we identified ultrastructural and molecular alterations in the postsynaptic region of synapses where NMDA receptors are localized as a multiprotein complex. We revealed decreased expression of several NMDA receptor complex-related proteins, such as GluN1 and GluN2B subunits, scaffolding proteins PSD95 and SynGAP, as well as neuronal nitric oxide synthase (nNOS). Elucidating the changes in NMDA receptor-mediated molecular mechanisms induced by AgNPs, we also identified downregulation of the GluN2B-PSD95-nNOS-cGMP signaling pathway which maintains LTP/LTD processes underlying learning and memory formation during development. This observation is accompanied by decreased density of NMDA receptors, as assessed by a radioligand binding assay. The observed effects are reversible over the post-exposure time. This investigation reveals that NMDA receptors in immature rats are a target of AgNPs, thereby indicating the potential health hazard for children and infants resulting from the extensive use of products containing AgNPs. 相似文献
145.
Wojciech Polkowski Natalia Sobczak Grzegorz Bruzda Artur Kudyba Rafal Nowak Adelajda Polkowska Izabela Krzak Adam Tchrz Donatella Giuranno 《SILICON》2020,12(7):1639-1649
Silicon-boron alloys have been recently pointed out as novel ultra-high temperature phase change materials for applications in Latent Heat Thermal Energy S 相似文献
146.
Aleksander Strugaa Jakub Jagielski Karol Kamel Grzegorz Nowaczyk Marcin Radom Marek Figlerowicz Anna Urbanowicz 《International journal of molecular sciences》2021,22(6)
Virus-like particles (VLPs), due to their nanoscale dimensions, presence of interior cavities, self-organization abilities and responsiveness to environmental changes, are of interest in the field of nanotechnology. Nevertheless, comprehensive knowledge of VLP self-assembly principles is incomplete. VLP formation is governed by two types of interactions: protein–cargo and protein–protein. These interactions can be modulated by the physicochemical properties of the surroundings. Here, we used brome mosaic virus (BMV) capsid protein produced in an E. coli expression system to study the impact of ionic strength, pH and encapsulated cargo on the assembly of VLPs and their features. We showed that empty VLP assembly strongly depends on pH whereas ionic strength of the buffer plays secondary but significant role. Comparison of VLPs containing tRNA and polystyrene sulfonic acid (PSS) revealed that the structured tRNA profoundly increases VLPs stability. We also designed and produced mutated BMV capsid proteins that formed VLPs showing altered diameters and stability compared to VLPs composed of unmodified proteins. We also observed that VLPs containing unstructured polyelectrolyte (PSS) adopt compact but not necessarily more stable structures. Thus, our methodology of VLP production allows for obtaining different VLP variants and their adjustment to the incorporated cargo. 相似文献
147.
Pawe Kowalczyk Mateusz Szymczak Magdalena Maciejewska ukasz Laskowski Magdalena Laskowska Ryszard Ostaszewski Grzegorz Skiba Ida Franiak-Pietryga 《International journal of molecular sciences》2021,22(2)
Silver and its nanoparticles (AgNPs) have different faces, providing different applications. In recent years, the number of positive nanosilver applications has increased substantially. It has been proven that AgNPs inhibit the growth and survival of bacteria, including human and animal pathogens, as well as fungi, protozoa and arthropods. Silver nanoparticles are known from their antiviral and anti-cancer properties; however, they are also very popular in medical and pharmaceutical nanoengineering as carriers for precise delivery of therapeutic compounds, in the diagnostics of different diseases and in optics and chemistry, where they act as sensors, conductors and substrates for various syntheses. The activity of AgNPs has not been fully discovered; therefore, we need interdisciplinary research to fulfil this knowledge. New forms of products with silver will certainly find application in the future treatment of many complicated and difficult to treat diseases. There is still a lack of appropriate and precise legal condition regarding the circulation of nanomaterials and the rules governing their safety use. The relatively low toxicity, relative biocompatibility and selectivity of nanoparticle interaction combined with the unusual biological properties allow their use in animal production as well as in bioengineering and medicine. Despite a quite big knowledge on this topic, there is still a need to organize the data on AgNPs in relation to specific microorganisms such as bacteria, viruses or fungi. We decided to put this knowledge together and try to show positive and negative effects on prokaryotic and eukaryotic cells. 相似文献
148.
Gombert Philippe Sracek Ondra Koukouzas Nikolaos Gzyl Grzegorz Valladares Susana Tuñon Frączek Robert Klinger Christoph Bauerek Arkadiusz Areces Juan Enrique Álvarez Chamberlain Sinead Paw Krzysztof Pierzchała Łukasz 《Mine Water and the Environment》2019,38(2):463-464
Mine Water and the Environment - Correct values for radium have been rewritten in Table 1 and Table 2. Correct radium units in Figure 2(c) are Bq/L (Becquerel per liter). The same applies to... 相似文献
149.
Summary Within the framework of coordinated pair systems a push-down automaton A is formalized as an ordered pair (G
1, G
2) of grammars, where G
1 is a right-linear grammar modelling the finite state control of A and the reading of the input of A, and G
2 is a right-boundary grammar modelling the push-down store of A. In this paper we present a systematic investigation into the use of memory of right-boundary grammars. Various methods of recording the use of memory are introduced. The results presented concern regularity properties of each of the methods and the interrelationships of the records obtained by different methods. Finally the translation of these results to the level of push-down automata (coordinated pair systems) is discussed. 相似文献
150.
A. D. Pomogailo A. S. Rozenberg G. I. Dzhardimalieva A. M. Bochkin S. I. Pomogailo N. D. Golubeva V. M. Grishchenko 《Inorganic Materials》2006,42(2):128-143
New types of hafnium-containing nanocomposites are prepared by combining polymer synthesis and controlled thermolysis. This approach involves the preparation and subsequent thermolysis of hafnium-containing polymers or concurrent solid-state polymerization of hafnium-containing monomers and thermal decomposition of the forming metal-containing polymer at different temperatures. The composition and structure of the synthesized hafnium-containing precursors and thermolysis products are determined by elemental analysis, IR spectroscopy, mass spectrometry, optical microscopy, and x-ray diffraction. Thermodynamic analysis is used to assess the equilibrium composition of the Hf-C-H-O system and establish the conditions under which HfC and HfO2 are formed. 相似文献