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211.
Fornari Raquel V.; Soares Juliana C. K.; Ferreira Tatiana L.; Moreira Karin M.; Oliveira Maria G. M. 《Canadian Metallurgical Quarterly》2008,122(1):98
Nociceptin, or orphanin FQ (N/OFQ), the endogenous ligand of NOP receptors, is known to regulate learning and memory processes. To verify the role of N/OFQ in the acquisition of contextual (CFC) and tone fear conditioning (TFC), Wistar male rats received intracerebroventricular injections of N/OFQ (0.1-5.0 nmol) before training, and were tested 24 and 48 hr later to access the freezing response to context and tone, respectively. The intermediate doses (1.0 and 2.5 nmol) impaired the CFC test, sparing TFC. The highest dose (5.0 nmol) reduced freezing during both tests, a result that may be due to nonspecific effects. The posttraining injection of N/OFQ (1 or 5 nmol) did not interfere with CFC and TFC, suggesting a specific effect of the peptide in acquisition processes. Moreover, the impairment observed with N/OFQ (1 nmol) in CFC cannot be attributed to a state-dependent learning because it was not reversed by its pretest administration. The data support the negative role of N/OFQ in the acquisition of aversively motivated tasks, which encompass a spatial component and depend on the hippocampus. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
212.
Submerged cultured higher basidiomycetes were screened for milk-clotting activity. The native liquid of Coprinus lagopides demonstrated high milk-clotting activity, while having relatively low general proteolytic activity. Optimization of growth media composition and ultrafiltration of the native liquid allows increasing the ratio of milk-clotting and proteolytic activities. The Enzyme was purified and characterized. 相似文献
213.
The purpose of this research is to seek evidence for viewer‐centered (especially aspect‐graph‐based) visual processing in the elementary task of object understanding. Two homologous, bilaterally symmetrical three‐dimensional (3‐D) objects have been employed that differ in that one is based on parts with flat surfaces and the other on parts with curved surfaces. The following procedure has been followed, separately for each object. In the training (saturated free inspection and manipulation) phase, a location (identical for both objects) of the object is marked with a red strip and the subjects' task is to memorize the object structure as well as the position of the strip. In the test phase, two‐dimensional views of the object without the strip are presented and the subjects' task is to determine whether the previously marked location should be visible or invisible in the particular view. Findings have been found consistent with an aspect‐graph‐based 3‐D object representation: (a) the reaction times and errors show characteristic dependencies on viewpoint; (b) a number of views (corresponding to certain aspects and aspect transitions of the aspect graph) consistently produce faster and more accurate recognition; (c) the differences in the aspect graphs of the two objects are reflected in differing patterns of reaction times and errors; furthermore; (d) the subjects impose a standard orientation on the objects, whereby a strong inversion effect is observed; and (e) performance varies in a similar way for both objects as a function of tilt. It is concluded that object understanding is viewpoint dependent, that is, based on a number of views. The characteristics of the views found to be most important for object understanding can be employed for creating efficient 3‐D object recognition machine vision systems. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 47–72, 2005. 相似文献
214.
Thibault Cousin Christophe Berto Tatiana Budtova Joanna Kurek Patrick Navard 《Polymer Engineering and Science》2017,57(5):563-569
Four processing tools (two twin‐screw extruders, one being a mini‐extruder, and two mixers) were used to prepare plasticized cellulose acetate with 20 wt% of glycerol triacetate. The goal was to deduce if the scale of the processing tool influences the dispersion of the plasticizer as estimated by the thermal, rheological, and mechanical properties of the obtained materials. The amount of polymer used ranged from 5 g for mini‐extruder to a 10 kg/h for pilot‐scale extruder. The specific mechanical energy was used to compare the thermal, rheological, and mechanical properties of cellulose acetate obtained with the four processing tools using different processing conditions. The measurement of the glass transition temperature was not able to discriminate the four tools used. Rheology shows differences, not as a function of small or large tools, but in terms of specific mechanical energy. The larger was the tool, the higher were the Young's moduli. This was ascribed to an overall better distribution and dispersion of the plasticizer. However, all variations were small, showing that small laboratory processing machines can prepare thermoplastic compounds with similar properties as pilot scale extruders, at least in what concerns cellulose acetate. POLYM. ENG. SCI., 57:563–569, 2017. © 2016 Society of Plastics Engineers 相似文献
215.
Stability of frozen fillets from silver catfish anesthetized with essential oil of Lippia alba prior to electrical stunning or hypothermia
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216.
Christopher N. Boyer Damian C. Adams Tatiana Borisova Christopher D. Clark 《Water Resources Management》2012,26(10):2747-2760
Water utilities typically set residential water prices using one of three rate structures: increasing block rate (IBR), uniform rate (UR), or decreasing block rate (DBR). Historically, DBR has been the most widely used residential rate structure, but water utilities are increasingly switching to a UR or IBR structure. The literature suggests several possible motivations for rate structure decisions, but provides little empirical evidence to support these suggestions and largely ignores the role of water managers?? attitudes and perceptions in the rate structure decision. The objective of this study is to statistically assess factors that drive rate structure changes, specifically toward UR or IBR, in the southern US. We designed and implemented a survey of water utility managers in Arkansas, Florida, Oklahoma, and Tennessee, including rural to urban water utilities. Survey questions were selected based on water utility manager input and literature review and included rate structure changes, system characteristics, and attitudes and perceptions about factors likely to influence rate structure changes. The rate structure adoption decision is modeled using both multinomial logit and Heckman probit specifications. Our results suggest that different factors drive the adoption of UR and IBR, including fair prices for end-users, qualifying for government grants/loans, revenue concerns, treatment cost increases, and infrastructure investment needs. 相似文献
217.
218.
Bastiaans MJ Alieva T 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(9):1763-1773
It is shown how all global Wigner distribution moments of arbitrary order in the output plane of a (generally anamorphic) two-dimensional fractional Fourier transform system can be expressed in terms of the moments in the input plane. Since Wigner distribution moments are identical to derivatives of the ambiguity function at the origin, a similar relation holds for these derivatives. The general input-output relationship is then broken down into a number of rotation-type input-output relationships between certain combinations of moments. It is shown how the Wigner distribution moments (or ambiguity function derivatives) can be measured as intensity moments in the output planes of a set of appropriate fractional Fourier transform systems and thus be derived from the corresponding fractional power spectra. The minimum number of (anamorphic) fractional power spectra that are needed for the determination of these moments is derived. As an important by-product we get a number of moment combinations that are invariant under (anamorphic) fractional Fourier transformation. 相似文献
219.
Two‐Photon Luminescence and Second‐Harmonic Generation in Organic Nonlinear Surface Comprised of Self‐Assembled Frustum Shaped Organic Microlasers
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220.
This paper provides novel empirical insights into the Porter hypothesis (PH) and its dynamic nature. The PH posits that well-designed environmental regulations induce eco-innovations at polluting firms that improve both their environmental and business performance via ‘innovation offsets.’ We conduct an econometric test of this proposition, using Swedish pulp and paper plants as empirical application. Swedish environmental regulation of polluting industries provides an interesting case because it has been praised, due to containing elements of ‘well-designed’ regulations, for being conducive to accomplishing the ‘win-win’ situation of mutual environmental and economic benefits. The empirical results indicate that flexible and dynamic command-and-control regulation and economic incentive instruments have induced innovation offsets through improved energy efficiency. Our study bears important implications: empirical tests of the PH that do not account for its dynamic nature, and that do not measure ‘well-designed’ regulations, might provide misleading conclusions as to its validity. 相似文献