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41.
This paper surveys recent research in deliberative real-time artificial intelligence (AI). Major areas of study have beenanytime algorithms, approximate processing, and large system architectures. We describe several systems in each of these areas, focusing both on progress within the field, and the costs, benefits and interactions among different problem and algorithm complexity limitations used in the surveyed work. 相似文献
42.
43.
Wioletta Rozpdek-Kamiska Grzegorz Galita Natalia Siwecka Steven L. Carroll John Alan Diehl Ewa Kucharska Dariusz Pytel Ireneusz Majsterek 《International journal of molecular sciences》2021,22(9)
Primary open-angle glaucoma (POAG) constitutes the most common type of glaucoma. Emerging evidence suggests that Endoplasmic Reticulum (ER) stress and the protein kinase RNA-like endoplasmic reticulum kinase (PERK)-mediated Unfolded Protein Response (UPR) signaling pathway play a key role in POAG pathogenesis. Thus, the main aim of the study was to evaluate the effectiveness of the PERK inhibitor LDN-0060609 in cellular model of glaucoma using primary human trabecular meshwork (HTM) cells. To evaluate the level of the ER stress marker proteins, Western blotting and TaqMan gene expression assay were used. The cytotoxicity was measured by XTT, LDH assays and Giemsa staining, whereas genotoxicity via comet assay. Changes in cell morphology were assessed by phase-contrast microscopy. Analysis of apoptosis was performed by caspase-3 assay and flow cytometry (FC), whereas cell cycle progression by FC. The results obtained have demonstrated that LDN-0060609 triggered a significant decrease of ER stress marker proteins within HTM cells with induced ER stress conditions. Moreover, LDN-0060609 effectively increased viability, reduced DNA damage, increased proliferation, restored normal morphology, reduced apoptosis and restored normal cell cycle distribution of HTM cells with induced ER stress conditions. Thereby, PERK inhibitors, such as LDN-0060609, may provide an innovative, ground-breaking treatment strategy against POAG. 相似文献
44.
Cinkilic Emre Moodispaw Michael Zhang Jianyue Miao Jiashi Luo Alan A. 《Metallurgical and Materials Transactions A》2022,53(8):2861-2873
Metallurgical and Materials Transactions A - The use of secondary aluminum for structural components in the automotive industry is limited by the high Fe contents in recycled alloys which often... 相似文献
45.
通过研究基片种类、加热温度、保温时间、冷却速度及是否加入催化剂等不同工艺参数对低维Ga2O3,纳米材料形貌的影响,确定出合成5种不同形貌β-Ga2O3纳米材料的工艺条件。场发射扫描电镜(FE-SEM)表明5种不同形貌α-Ga2O3纳米材料分别为纳米线、纳米棒、纳米带、纳米环及纳米片。X射线衍射(X-ray)分析结果表明不同形貌纳米材料均为晶格常数日=1.223nm,b=0.304nm,c=0.58nm,a=90°,β=103.7°,γ=90°的单斜晶系β-Ga2O3晶体。 相似文献
46.
An examination of the influence of pressure and heating rate on the thermoplastic properties of a weakly coking coal and of coal with various pitch-like additives was carried out using a high pressure dilatometer. Pressure up to 4 MPa markedly increased the swelling properties and increased the plastic range by decreasing the softening temperature, but the effects of pressure were strongly influenced by rate of heating with high heating rates enhancing the effects. Additions of tar or pitch also enhanced swelling at low pressure. The solid carbonization residues from the dilatometer were examined by polarized light microscopy to determine the content and composition of optically anisotropic species. The anisotropic content was increased by increases in pressure and heating rate and pitch additives enhanced the anisotropic content, especially at low pressure, without affecting the composition of the anisotropy. No direct correlations exist between the dilatometric parameters and the optical anisotropy but their dependence on the conditions emphasizes that when considering high pressure gasification of coal, it is necessary to obtain data under appropriate conditions. 相似文献
47.
Aromaticities determined by 13C n.m.r. are reported for five shale oil samples (Green River formation) prepared under widely different pyrolysis conditions. In the absence of high-pressure hydrogen, the total amount of aromatic carbon in the products is nearly twice that in the raw shale. This is true for a wide range of pyrolysis conditions, although the distribution of aromatic carbon between the oil and carbonaceous residue changes. High-pressure hydrogen appears to inhibit both the formation of additional aromatic carbon during pyrolysis and the coking of aromatic oil. An improved kerogen decomposition mechanism is reported that accounts for these effects and provides for changes in the aromaticity of the liquid product with pyrolysis conditions. Further work is necessary to make it quantitative and account for gas formation. 相似文献
48.
Male rats were fed 100 nM dichlorodiphenyltrichloroethane-14C in oil by gastric tube. Recovery of dichlorodiphenyltrichloroethane-14C in thoracic duct lymph was 60% in 12 hr. Lymph dichlorodiphenyltrichloroethane-14C (97%) occurred in lipoproteins of d<1.006, designated chylomicrons. Mechanical separation of chylomicron triglyceride core
(labeled with triglyceride-3H) from chylomicron membrane (labeled with phospholipid-32P) showed that 97% dichlorodiphenyltrichloroethane-14C was present in triglyceride core. To investigate possible association of plasma clearance of the two core lipids, rats were
pulse injected with chylomicrons, doubly labeled with triglyceride-3H and dichlorodiphenyltrichloroethane-14C. The decay of dichlorodiphenyltrichloroethane-14C in sequential serum samples was rapid (T1/2=2 min) and was independent of triglyceride-3H decay. In tissues removed 14 min after injection of chylomicrons, 30% administered dichlorodiphenyltrichloroethane-14C was found in liver but only 1% in adipose tissue. In hepatectomized (eviscerated) rats, the decay of serum dichlorodiphenyltrichloroethane-14C (T1/2=10 min) was also independent of and more rapid than triglyceride-3H decay. With sucrose density gradients, it was shown that chylomicron dichlorodiphenyltrichloroethane-14C transferred to higher density serum proteins in vitro and in vivo and to bovine albumin in vitro. Thus, dichlorodiphenyltrichloroethane
was transported from intestine largely in the triglyderide phase of chylomicrons; disappearance of chylomicron-dichlorodiphenyltrichloroethane
from the systemic circulation was rapid and partly independent of the presence of the liver and of triglyceride hydrolysis;
some dichlorodiphenyltrichloroethane was transported from serum chylomicrons to albumin or other plasma proteins before tissue
uptake. 相似文献
49.
Theresa E. Gentle Alan R. Bassindale 《Journal of Inorganic and Organometallic Polymers》1995,5(3):281-294
We have recently reported the synthesis of octopus molecules of defined shape and size with molecular weights well into the thousands. These octopus molecules were made by placing eight pendant groups symmetrically about a central silsesquioxane core via the H2PtCl6 catalyzed hydrosilylation of 1-alkenes as well as vinyl- and allyl-siloxanes by T8 hydrogen silsesquioxane, (HSiO32)8. The chemistry of addition was studied and it was found that while the addition of the 1-alkenes to T8 was regioprecise with only -addition being observed, both - and -addition occurred with vinyl-siloxane. In addition, H-vinyl exchange on silicon was observed to occur with addition of vinyl-siloxane to T8. In the current studies, the effect of the hydrosilylation catalyst. homogeneous and heterogeneous, on the regioselectivity of addition and on the extent of exchange on silicon was evaluated. It was found that the heterogeneous catalysts Pt–C, sulfided Pt–C, and Rh–C required higher temperature and longer times to get complete reaction than the homogeneous catalysts. H2PtCl6 and the tetramethyldivinyldisiloxane complex of Pt. Pd supported catalysts were not effective catalysts for this hydrosilylation. The extent of exchange on silicon and the degree of the second mode of addition occurring were higher with the heterogenous catalysts and may be a result of the higher reaction temperatures. 相似文献
50.
In industrial situations, coals interact with solvents or additives to produce liquid fuels, solvent-refined coal, coal extract and metallurgical coke. In these processes there occurs a wide variation in effects or modifications of the coal by these additives. This paper describes the modifications which can occur, using a wide range of rank of coal, when these coals interact and are co-carbonized with a wide range of additives of different chemical properties. The optical texture of the resultant cokes is given special attention. The objective of the paper is to summarize the current state of knowledge of the mechanisms of these interactions. Possible mechanisms of interactions are summarized, kinetic and chemical structural aspects of reactions are outlined, the importance is mentioned of the formation of liquid phases enabling anisotropic optical textures in modified cokes to be created, and the industrial relevance of its possible development is discussed. 相似文献