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991.
Martins Júnior W De Rossi A Samih Georges Abi Rached R Rossi MA 《Journal of electron microscopy》2011,60(2):167-175
In the present investigation, a scanning electron microscopy analysis was performed to evaluate the effects of the topical application of ethylenediaminetetraacetic acid (EDTA) gel associated with Cetavlon (EDTAC) in removing the smear layer and exposing collagen fibers following root surface instrumentation. Twenty-eight teeth from adult humans, single rooted and scheduled for extraction due to periodontal reasons, were selected. Each tooth was submitted to manual (scaling and root planing) instrumentation alone or combined with ultrasonic instruments, with or without etching using a 24% EDTAC gel. Following extraction, specimens were processed and examined under a scanning electron microscope. A comparative morphological semi-quantitative analysis was performed; the intensity of the smear layer and the decalcification of cementum and dentinal surfaces were graded in 12 sets using an arbitrary scale ranging from 1 (area covered by a smear layer) to 4 (no smear layer). Root debridement with hand instruments alone or combined with ultrasonic instruments resulted in a similar smear layer covering the root surfaces. The smear layer was successfully removed from the surfaces treated with EDTAC, which exhibited numerous exposed dentinal tubules and collagen fibers. This study supports the hypothesis that manual instrumentation alone or instrumentation combined with ultrasonic instrumentation is unable to remove the smear layer, whereas the subsequent topical application of EDTAC gel effectively removes the smear layer, uncovers dentinal openings and exposes collagen fibers. 相似文献
992.
Mahoney Kevin T.; Buboltz Walter C. Jr.; Buckner V John E.; Doverspike Dennis 《Canadian Metallurgical Quarterly》2011,16(4):406
An online survey was conducted on a national sample of United States professors to examine emotional labor and its relationship to work outcomes. Participants were queried on genuine, faking, and suppressing emotional expression facets of emotional labor, as well as emotional exhaustion, job satisfaction, and affective commitment. The sample of 598 included 71 instructors, 177 assistant professors, 168 associate professors, and 182 professors. A path analysis was conducted testing two models of emotional labor. Results supported a model indicating significant direct relationships between emotional labor, emotional exhaustion, and job satisfaction. Additionally, the relationship between emotional labor and affective commitment was mediated by emotional exhaustion and job satisfaction. Genuine positive expression was the only emotional labor variable to have significant direct relationships with all outcomes. For U.S. faculty, the experience of emotional labor was related to several work attitudes. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
993.
Siyanova-Chanturia Anna; Conklin Kathy; van Heuven Walter J. B. 《Canadian Metallurgical Quarterly》2011,37(3):776
Are speakers sensitive to the frequency with which phrases occur in language? The authors report an eye-tracking study that investigates this by examining the processing of multiword sequences that differ in phrasal frequency by native and proficient nonnative English speakers. Participants read sentences containing 3-word binomial phrases (bride and groom) and their reversed forms (groom and bride), which are identical in syntax and meaning but that differ in phrasal frequency. Mixed-effects modeling revealed that native speakers and nonnative speakers, across a range of proficiencies, are sensitive to the frequency with which phrases occur in English. Results also indicate that native speakers and higher proficiency nonnatives are sensitive to whether a phrase occurs in a particular configuration (binomial vs. reversed) in English, highlighting the contribution of entrenchment of a particular phrase in memory. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
994.
Walter Ambrosini 《Nuclear Engineering and Design》2011,241(12):5149-5173
In this paper, a rationale for comparing heat transfer behaviour of different fluids at supercritical pressures is discussed. The study is performed as an extension to heat transfer of a previous proposal of dimensionless groups suitable for assessing stability in heated channels with supercritical fluids. The additional difficulty to be overcome with respect to the case of stability of channels with imposed heat flux is related to the role played in the present case by thermo-physical properties, whose trends as a function of dimensionless enthalpy are different for different fluids, sharing anyway a general similarity across the pseudo-critical threshold.The proposed considerations are discussed with the aid of results obtained by computational fluid-dynamic codes, contributing to clarify the extent at which the reported considerations can be considered promising for developing a coherent similarity theory for heat transfer to fluids at supercritical pressures. 相似文献
995.
小麦适度碾皮一种提高面粉品质及附加值的技术 总被引:1,自引:0,他引:1
提高原料小麦利用效率及其面粉品质,始终是制粉业需要不断解决的根本问题.为此,制粉业的加工设备和工艺一直在不断地创新. 制粉的小麦最好能够在碾磨之前除去其外皮,然而,采取常规的技术和工艺,这是不可能的. 相似文献
996.
Walter E. Hill Dr. Kaye Wachsmuth 《Critical reviews in food science and nutrition》1996,36(1-2):123-173
Faster methods for the detection of foodborne microbial pathogens are needed. The polymerase chain reaction (PCR) can amplify specific segments of DNA and is used to detect and identify bacterial genes responsible for causing diseases in humans. The major features and requirements for the PCR are described along with a number of important variations. A considerable number of PCR‐based assays have been developed, but they have been applied most often to clinical and environmental samples and more rarely for the detection of foodborne microorganisms. Much of the difficulty in implementing PCR for the analysis of food samples lies in the problems encountered during the preparation of template DNAs from food matrices; a variety of approaches and considerations are examined. PCR methods developed for the detection and identification of particular bacteria, viruses, and parasites found in foods are described and discussed, and the major features of these reactions are summarized. 相似文献
997.
The mass flows of fluoroquinolone antibacterial agents (FQs) were investigated in the aqueous compartments of the Glatt Valley Watershed, a densely populated region in Switzerland. The major human-use FQs consumed in Switzerland, ciprofloxacin (CIP) and norfloxacin (NOR), were determined in municipal wastewater effluents and in the receiving surface water, the Glatt River. Individual concentrations in raw sewage and in final wastewater effluents ranged from 255 to 568 ng/L and from 36 to 106 ng/L, respectively. In the Glatt River, the FQs were present at concentrations below 19 ng/L. The removal of FQs from the water stream during wastewater treatment was between 79 and 87%. During the studied summer period, FQs in the dissolved fraction were significantly reduced downstream in the Glatt River (15-20 h residence time) (66% for CIP and 48% for NOR). Thus, after wastewater treatment, transport in rivers causes an additional decrease of residual levels of FQs in the aquatic environment. Refined predicted environmental concentrations for the study area compare favorably with the measured environmental concentrations (MEC) obtained in the monitoring study. Total measured FQ concentrations occurring in the examined aquatic compartments of the Glatt Valley Watershed were related to acute ecotoxicity data from the literature. The risk quotients obtained (MEC/PNEC < 1) following the recommendations of the European guidelines or draft documents suggest a low probability for adverse effects of the occurring FQs, either on microbial activity in WWTPs or on algae, daphnia, and fish in surface waters. 相似文献
998.
WalterBlum 《中华纸业》2004,25(9):25-26
无反作用力的摇振器-DuoShake,已应用于低速机至1200m/min高速纸机,定量范围18~550g/m2,已在中国、欧洲、北美和南美的70台纸机上应用. 相似文献
999.
Achille Peternier Cesare Pautasso Walter Binder Daniele Bonetta 《Concurrency and Computation》2014,26(1):71-97
Although modern computer hardware offers an increasing number of processing elements organized in nonuniform memory access (NUMA) architectures, prevailing middleware engines for executing business processes, workflows, and Web service compositions have not been optimized for properly exploiting the abundant processing resources of such machines. Amongst others, factors limiting performance are inefficient thread scheduling by the operating system, which can result in suboptimal use of system memory and CPU caches, and sequential code sections that cannot take advantage of multiple available cores. In this article, we study the performance of the JOpera process execution engine on recent multicore machines. We first evaluate its performance without any dedicated optimization for multicore hardware, showing that additional cores do not significantly improve performance, although the engine has a multithreaded design. Therefore, we apply optimizations on the basis of replication together with an improved, hardware‐aware usage of the underlying resources such as NUMA nodes and CPU caches. Thanks to our optimizations, we achieve speedups from a factor of 2 up to a factor of 20 (depending on the target machine) when compared with a baseline execution ‘as is’. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
1000.
lvaro Rubio‐Largo Miguel A. Vega‐Rodríguez David L. Gonzlez‐lvarez 《Concurrency and Computation》2014,26(11):1908-1934
The future of designing optical networks focuses on the wavelength division multiplexing technology. This technology divides the huge bandwidth of an optical fiber into different wavelengths, providing different available channels per link of optical fiber. However, when it is required to establish a set of demands, a problem comes up. This problem is known as routing and wavelength assignment problem. In this work, we have tackled the static routing and wavelength assignment problem by using multiobjective evolutionary computing. The algorithm applied is the differential evolution but modified with the Pareto tournaments concept for being adapted to the multiobjective context. By using OpenMP, an application programming interface that supports multiplatform shared memory multiprocessing programming, we have demonstrated that this algorithm is highly suitable to be parallelized. We have performed several experiments in multicore systems with two, four, and eight cores, obtaining 97.57% of mean efficiency. To ensure that our heuristic obtains relevant results, we have compared it with a parallel version of the standard fast nondominated sorting genetic algorithm. Finally, in order to show the goodness and effectiveness of the differential evolution with Pareto tournaments algorithm when dealing with this problem, we present diverse multiobjective comparisons with the nondominated sorting genetic algorithm and other approaches published in the literature. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献