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41.
42.
Arne Skauge Kristine Spildo Linda Hiland Bartek Vik 《Journal of Petroleum Science and Engineering》2007,57(3-4):321-333
In this paper we analyze data from thirteen North Sea sandstone reservoirs that fall into the large group of intermediate wettability. By dividing this group into three sub-classes, fractionally-wet (FW), mixed-wet large (MWL) and mixed-wet small (MWS), we find an improved understanding of the intermediate-wet state. In the fractionally-wet state oil- and water-wet sites are random with respect to size, while in the mixed-wet state water- and oil-wet pores are sorted by size. We assume two classes of mixed wettability; MWL where the large pores are oil-wet and MWS where the small pores are oil-wet. The paper includes both theoretical considerations, pore–scale observations by ESEM, SEM and thin sections, as well as core scale wettability indices that indicate that these wettability states may exist in reservoirs. 相似文献
43.
HU Andersen PM Larsen SJ Fey AE Karlsen T Mandrup-Poulsen J Nerup 《Canadian Metallurgical Quarterly》1995,44(4):400-407
Interleukin (IL)-1 beta-mediated damage to beta-cells in isolated islets of Langerhans depends upon de novo synthesis of proteins that have not been fully identified. Further, IL-1 beta-induced and tumor necrosis factor alpha-induced islet damage partly depends on the intracellular production of the nitric oxide (NO) radical. IL-1 beta has also been reported to induce the synthesis of cellular defense proteins, e.g., heme-oxygenase and heat shock proteins 70 and 90. Nicotinamide, while in itself inactive, inhibited IL-1 beta-induced NO production in a time- and dose-dependent manner. To enable the identification of IL-1 beta-induced proteins with possible protective and deleterious effects, we characterized the effects of IL-1 beta, nicotinamide, and NO synthesis inhibition by L-arginine depletion on rat islet protein expression detected by high-resolution two-dimensional gel electrophoresis. More than 1,600 proteins were reproducibly detected in control rat islets. Incubation with IL-1 beta-, nicotinamide-, or L-arginine-depleted control medium upregulated 29, 3, and 1 protein, respectively, and downregulated 4, 0, and 1 protein, respectively. Addition of nicotinamide and L-arginine depletion reduced the upregulation of 16 and 20 IL-1 beta-induced proteins, respectively. The identity of these proteins is under study. The demonstrated changes in protein expression caused by IL-1 beta +/- nicotinamide and L-arginine depletion may form the basis for identification of proteins with possible protective and deleterious roles in the initial beta-cell destruction in insulin-dependent diabetes mellitus. 相似文献
44.
80 children in Grades 5 and 6 were administered the General and Test Anxiety Scales for Children, and the Defensiveness Scale for Children. Although girls scored higher than boys on the anxiety measures, there were no differences on the Defensiveness Scale, suggesting that the content of the scales, rather than defensiveness, merits further investigation. There were no differences between Black and White children on any of the measures. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Gun deaths and injuries in Canada are a serious public health problem, claiming more than 1200 lives each year and resulting in over 1000 hospitalizations. While the issue has been hotly debated in recent years, considerable research in an international context suggests that there is a relationship between access to firearms and deaths and injuries caused by firearms. Interventions to reduce access to firearms include regulation, education and engineering. Legislative reforms aimed at reducing gun deaths and injuries have been introduced recently in Canada and in many other countries. Although domestic controls can affect the supply of guns, efforts are being co-ordinated increasingly on an interjurisdictional basis to decrease the illegal trafficking of firearms. As well, the United Nations Crime Prevention and Criminal Justice Commission recently passed a resolution encouraging all countries who have not done so to strengthen their domestic gun controls since weak controls in one country can affect security in others. 相似文献
46.
Guillain-Barré syndrome, or acute inflammatory demyelinating polyneuropathy, is a frequent cause of acute onset of flaccid paresis and areflexia. Electrophysiological studies show demyelination, sometimes with varying degrees of axonal degeneration. In some cases axonal degeneration apparently develops rapidly, without signs of primary demyelination. However, it is still a matter of discussion whether a pure axonal form of Guillain-Barré syndrome exists, or whether the axonal degeneration is secondary to demyelination. We report on clinical and electrophysiological findings in three patients with variants of Guillain-Barré syndrome. These include pure demyelination, combined demyelination and axonal degeneration and possible primary axonal degeneration. Electrophysiological studies can differentiate between the variants of Guillain-Barré syndrome, and thus give indications of pathogenesis and prognosis. 相似文献
47.
Toxicants may affect juveniles more than adults because of physiological and behavioral aspects. When developing toxicity tests, this issue is often not addressed, and the most sensitive end point may be ignored. The topic was raised by a European working group aiming to develop a standard toxicity test with the predatory mite, Hypoaspis (Geolaelaps) aculeifer Canestrini, as this species was included in the EU Guidance documentfortesting of pesticides. To assess whether the juvenile life stages are the most susceptible, we examined the acute toxicity of dimethoate on larvae, protonymphs, deutonymphs, males, and females of H. aculeifer. The mites were exposed to 0, 2, 4, and 6 mg dimethoate kg(-1) for 7 days in an OECD artificial soil (5% organic matter). Total juvenile biomass, reproduction, mortality, and population growth rate (pgr) lambda were assessed at the end of the test. A comparison of mortality ranked the sensitivity of the life stages: Larvae (LC50 = 3.8 mg kg(-1)) > protonymphs (LC50 = 5.3 mg kg(-1)) > males (LC50 = 5.6 mg kg(-1)) > deutonymphs (LC50 = 7.1 mg kg(-1)) > females (LC50 = 7.6 mg kg(-1)). Effects on reproduction and pgr were significant at 2 mg dimethoate kg(-1), with population decline starting at this concentration. Thus, a test system with H. aculeifer including reproduction as end point is a rational approach, as reproduction will encompass juvenile mortality, at least with respect to dimethoate. Moreover, we suggest that pgr should be included in chronic standard tests because of high ecological relevance and the feasibility of applying it. 相似文献
48.
Nerea Mascaraque Kacper Januchta Kristine F. Frederiksen Randall E. Youngman Mathieu Bauchy Morten M. Smedskjaer 《Journal of the American Ceramic Society》2019,102(3):1157-1168
Alkali and alkaline earth aluminoborate glasses feature high resistance to cracking under sharp contact loading compared to other oxide glasses. However, due to the high content of hygroscopic B2O3, it is expected that applications of these glasses could be hindered by poor chemical durability in aqueous solutions. Indeed, the compositional and structural dependence of their dissolution kinetics remains unexplored. In this work, we correlate the dissolution rates of aluminoborate glasses in acidic, neutral, and basic solutions with the structural changes induced by varying the aluminum-to-boron ratio. In detail, we investigate a total of seventeen magnesium, lithium, and sodium aluminoborate glasses with fixed modifier content of 25 mol%. We show that the structural changes induced by alumina depend on the network modifier. We also demonstrate a correlation between the chemical durability at various pH values and the structural changes in Mg-, Li- and Na-aluminoborate glasses. The substitution of alumina by boron oxide leads to a general decrease in chemical corrosion in neutral and acidic solutions. The lowest dissolution rate value is observed in Mg-aluminoborate glasses, as a consequence of the intermediate character of magnesium which can increase the network cross-linking. For basic solutions, the chemical durability is almost constant for the different amount of alumina in the three series, likely because B2O3 is susceptible to nucleophilic attack, which is favored in high-OH− solutions. 相似文献
49.
50.
Kristine Drew Sybille Hopman Matthias Hrteis Stefan W. Glunz Filip Granek 《Progress in Photovoltaics: Research and Applications》2011,19(3):253-259
First results showing the viability of combining laser chemical processing (LCP) and aerosol jet printing (AJP) technologies to produce a high‐efficiency front side for silicon solar cells are presented. LCP simultaneously opens the anti‐reflection coating (ARC) and highly dopes the underlying silicon to create a selective emitter, while AJP is the first in a two‐step fine‐line contact formation procedure. The electrical properties as well as the morphology of the resulting structures are presented. Performance similar to that achieved with evaporated TiPdAg metallization is demonstrated. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献