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71.
Two issues are discussed. The first one pertains to the generality of the nonconscious learning processes and their somewhat paradoxical status in cognitive psychology. We argue that the ability of the human cognitive system to nonconsciously acquire complex knowledge structures is one of its elementary and indispensable properties. Moreover, the existence of this ability constitutes one of the necessary metatheoretical assumptions of contemporary cognitive psychology. Nevertheless, the contemporary cognitive psychology literature often implies that it is only one of many controversial and unusual phenomena. The second issue pertains to the distinction between the so-called primitive unconscious and the sophisticated unconscious as proposed by A. S. Reber (see record 1989-38920-001). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The mechanical response of single-walled and multiwalled carbon nanotubes to a series of external Ar atom impacts is examined with classical molecular dynamics simulations. The extent to which the carbon nanotubes deform in the direction perpendicular to their axis is found to depend on the amount of momentum transferred during the collisions. The details of the mechanical response and recovery of the nanotubes after release are also found to depend on the nanotube configurations. 相似文献
74.
The paper deals with the problem of minimizing the expected makespan in a two-machine flow shop with blocking and random job
processing times. It is well known that it reduces to an instance of the traveling salesman problem (TSP). Assuming that the
job processing times can be stochastically ordered on both machines, we show that the problem under study is equivalent to
TSP on a permuted Monge matrix. This allows us to prove that it is NP-hard for the independently and exponentially distributed
job processing times, and identify a new class of efficiently solvable special cases. 相似文献
75.
Zbigniew Jedliński Andrej Stolarzewicz Pawel Szewczyk Ryszard Tymczyński 《Polymer Bulletin》1980,2(8):555-563
Summary Polymerization of p-chlorophenyl glycidyl ether initiated by potassium glycolates (ethylene, propylene and 2-methyl propylene glycolatea) in DMSO containing some 18-crown-6 ether or glycol was investigated. For the reaction system containing the propylene glycolate asymmetrically substituted with a methyl group, relatively high polymerization rates were obtained as compared with those found for the other systems studied, the resultant polymers also having higher molecular weights and comparatively low polydispersities. Aliphatic double bonds were found to be absent in the polymers synthesized, which would suggest that in the anionic polymerization process studied the growing chain is not transferred to the monomer.Dedicated to Prof. C.I. Simionescu on the occasion of the 60th anniversary of his birthday 相似文献
76.
Soares C Drupieski C Wingert B Pritchett G Pagonis V O'Brien M Sliski A Bilski P Olko P 《Radiation protection dosimetry》2006,120(1-4):78-82
Absorbed dose rate measurements of a 50 kV(p) handheld X-ray probe source in a water phantom are described. The X-ray generator is capable of currents of up to 40 microA, and is designed for cranial brachytherapy and intraoperative applications with applicators. The measurements were performed in a computer-controlled water phantom in which both the source and the detectors are mounted. Two different LiF thermoluminescence dosemeter (TLD) phosphors were employed for the measurements, MTS-N (LiF:Mg,Ti) and MCP-N (LiF:Mg,Cu,P). Two small ionisation chambers (0.02 and 0.0053 cm(3)) were also employed. The TLDs and chambers were positioned in watertight mounts made of water-equivalent plastic. The chambers were calibrated in terms of air-kerma rate, and conventional protocols were used to convert the measurements to absorbed dose rate. The TLDs were calibrated at National Institute of Standards and Technology (NIST) in terms of absorbed dose rate using a (60)Co teletherapy beam and narrow-spectrum X-ray beams. For the latter, absorbed dose was inferred from air-kerma rate using calculated air-kerma-to-dose conversion factors. The reference points of the various detectors were taken as the center of the TLD volumes and the entrance windows of the ionisation chambers. Measurements were made at distances of 3-45 mm from the detector reference point to the source center. In addition, energy dependence of response measurements of the TLDs used was made using NIST reference narrow spectrum X-ray beams. Measurement results showed reasonable agreement in absorbed dose rate determined from the energy dependence corrected TLD readings and from the ionisation chambers. Volume averaging effects of the TLDs at very close distances to the source were also evident. 相似文献
77.
Janczyk P Trevisi P Souffrant WB Bosi P 《International journal of food microbiology》2008,126(1-2):258-261
Thirty two weaned pigs (24 d-old) were fed a diet without or with 1% (w/w) thymol. Pigs from each dietary treatment remained unchallenged or were challenged with Salmonella enterica serovar typhimurium. Jejunal content was collected and molecular microbial diversity was investigated using 16S rRNA gene polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Shannon index analysis showed no differences in diversity but Pearson coefficient analysis showed clear clustering of profiles, which delineated thymol fed and control groups irrespective of Salmonella challenge. Moreover, absence of bands corresponding to Actinobacillus minor (98-99% identity) was observed in thymol groups. A band corresponding to Citrobacter freundii (98% identity) was observed in almost all pigs from thymol groups, and only in 4 samples from pigs fed no thymol in the diet. Supplementation of pig diet with thymol caused clear changes in small intestine microbacterial community. Surprisingly, Salmonella infection caused no major perturbations to the community structure. 相似文献
78.
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80.
Railean-Plugaru Viorica Pomastowski Pawel Buszewski Boguslaw 《Journal of dairy science》2021,104(3):2480-2498
The present research emphasizes the use of safe, inexpensive, and available whey using Lactobacillus paracasei as a source in silver nanocomposite synthesis as an alternative bioactive agent for dairy and biomedical applications. Through the multiinstrumental approach used in this study based on spectroscopic and microscopic methods as well as spectrometric techniques, the characterization and evaluation of silver composites and their antimicrobial and antiradical properties were enabled. Synthesized silver nanocomposites have been found in form of nanocrystals, naturally coated by an organic surface with high antimicrobial and antiradical properties. Furthermore, this work also presents an innovative approach regarding the organic surface (naturally secreted by the bacteria isolated from whey) of the core of nanoparticles, which has already been explored and therefore is starting to supplement the scientific approach concerning biologically synthesized nanoparticles. This work also presents a general frame on the resistance subject by performing the trial interaction of commercially available antibiotics (kanamycin and ampicillin) with new bioactive compounds that can create novel knowledge on complementing their action. Moreover, synthesized silver nanocomposites have shown great antioxidant and antimicrobial effects against various foodborne pathogens from dairy products and drug resistance pathogens found in the medical area to rank on the top of mortality rate. 相似文献