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991.
Reviews the book, Evolutionary cognitive neuroscience edited by Steven M. Platek, Julian Paul Keenan, and Todd K. Shackelford (2007). This book demonstrates that now scientists can hop back and forth--examining archaeological and palaeontological, genetic, phylogentic, developmental, and even online neuroimaging evidence in a compelling enterprise of converging operations. The first few chapters do a very nice job of bringing readers together with some requisite concepts--natural and sexual selection, inclusive reproductive fitness, adaptation, and so on. The second and third sections of the book provide provocative accounts of work with humans, nonhuman primates, cetaceans (whales and dolphins), and even cichlid fishes. The book concludes with some cautionary commentaries about avoiding invalid moral conclusions from the study of evolutionary cognitive neuroscience. This book shows that, in some fields, it's all starting to come together. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
992.
Beran Michael J.; Harris Emily H.; Evans Theodore A.; Klein Emily D.; Chan Betty; Flemming Timothy M.; Washburn David A. 《Canadian Metallurgical Quarterly》2008,122(1):52
Ordinal learning was investigated in capuchin monkeys (Cebus apella) and rhesus monkeys (Macaca mulatta). In Experiment 1, both species were presented with pairings of the Arabic numerals 0 to 9. Some monkeys were given food rewards equal to the value of the numeral selected and some were rewarded with a single pellet only for choosing the higher numeral within the pair. Both species learned to select the larger numeral, but only rhesus monkeys that were differentially rewarded performed above chance levels when presented with novel probe pairings. In Experiment 2, the monkeys were first presented with arrays of 5 familiar numerals (from the range 0 to 9) and then arrays of 5 novel letters (from the range A to J) with the same reward outcomes in place as in Experiment 1. Both species performed better with the numerals, suggesting that an ordinal sequence of all stimuli had been learned during Experiment 1, rather than a matrix of two-choice discriminations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
N. D. Weinstein (1980) established that optimistic bias, the tendency to see others as more vulnerable to risks than the self, varies across types of event. Subsequently, researchers have documented that this phenomenon, also known as comparative optimism, also varies across types of people. The authors integrate hypotheses originally advanced by Weinstein concerning event-characteristic moderators with later arguments that such optimism may be restricted to certain subgroups. Using multilevel modeling over 7 samples (N = 1,436), the authors found that some degree of comparative optimism was present for virtually all individuals and events. Holding other variables constant, higher perceived frequency and severity were associated with less comparative optimism, higher perceived controllability and stereotype salience with more comparative optimism. Frequency, controllability, and severity were associated more with self-risk than with average-other risk, whereas stereotype salience was associated more with average-other risk than with self-risk. Individual differences also mattered: comparative optimism was related negatively to anxiety and positively to defensiveness and self-esteem. Interaction results imply that both individual differences and event characteristics should jointly be considered in understanding optimistic bias (or comparative optimism) and its application to risk communication. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Results of density and viscosity measurements for aqueous solutions of MgCl2 (0.5–3.5 mol L− 1) and MgCl2 + 10% NiCl2 (0.5–3.5 mol L− 1) at temperatures of 25, 60 and 90 °C show an almost linear increase in density with total concentration, while low nickel contents and temperature have comparatively small effects. Viscosities of MgCl2 solutions rise sharply at 25 °C but are significantly lower at 90 °C. The viscosity of 3–4 mol kg− 1 MgCl2 at 90 °C is similar to water at 25 °C. Nickel has no significant effect on the viscosity of these solutions.Results of heat capacity measurements for aqueous solutions of MgCl2 (0.5–3.5 mol L− 1) and MgCl2 + 10% NiCl2 (0.5–3.5 mol L− 1) at temperatures of 60 and 90 °C show that the heat capacities of these solution decrease significantly with total concentration, while the effects of low nickel contents and temperature are again comparatively small. 相似文献
995.
A Composite of Carbon‐Wrapped Mo2C Nanoparticle and Carbon Nanotube Formed Directly on Ni Foam as a High‐Performance Binder‐Free Cathode for Li‐O2 Batteries
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Qian‐Cheng Zhu Shu‐Mao Xu Michelle M. Harris Chao Ma Yu‐Si Liu Xiao Wei Hua‐Sheng Xu Yong‐Xian Zhou Yu‐Cai Cao Kai‐Xue Wang Jie‐Sheng Chen 《Advanced functional materials》2016,26(46):8514-8520
Cathode design is indispensable for building Li‐O2 batteries with long cycle life. A composite of carbon‐wrapped Mo2C nanoparticles and carbon nanotubes is prepared on Ni foam by direct hydrolysis and carbonization of a gel composed of ammonium heptamolybdate tetrahydrate and hydroquinone resin. The Mo2C nanoparticles with well‐controlled particle size act as a highly active oxygen reduction reactions/oxygen evolution reactions (ORR/OER) catalyst. The carbon coating can prevent the aggregation of the Mo2C nanoparticles. The even distribution of Mo2C nanoparticles results in the homogenous formation of discharge products. The skeleton of porous carbon with carbon nanotubes protrudes from the composite, resulting in extra voids when applied as a cathode for Li‐O2 batteries. The batteries deliver a high discharge capacity of ≈10 400 mAh g?1 and a low average charge voltage of ≈4.0 V at 200 mA g?1. With a cutoff capacity of 1000 mAh g?1, the Li‐O2 batteries exhibit excellent charge–discharge cycling stability for over 300 cycles. The average potential polarization of discharge/charge gaps is only ≈0.9 V, demonstrating the high ORR and OER activities of these Mo2C nanoparticles. The excellent cycling stability and low potential polarization provide new insights into the design of highly reversible and efficient cathode materials for Li‐O2 batteries. 相似文献
996.
Cesar Ovalles Estrella Rogel Harris Morazan Kaidong Chen Michael E. Moir 《Petroleum Science and Technology》2016,34(4):379-385
This work focused on the synthesis and characterization of nonylphenol formaldehyde resins (NPFR) as examples of active molecules for preventing asphaltene precipitation in vacuum residue (VR) and hydroprocessed petroleum samples. The evaluation for the NPFR as asphaltene dispersants was carried out using the on-column filtration technique at room temperature and near process conditions (195°C). The results indicated that NPFR (molecular weight = 900–4800 Da) are active for the reduction of asphaltene content of gravimetrically separated asphaltene solutions and for VR and hydroprocessed samples at room temperature (35°C) and at 195°C. It was found that the activity of NPFR as asphaltene dispersants depends not only on the type of sample (asphaltenes, virgin or processed) but also on the temperature, molecular weight, and concentration. 相似文献
997.
Bailey AO Miller TM Dong MQ Vande Velde C Cleveland DW Yates JR 《Analytical chemistry》2007,79(16):6410-6418
Multidimensional liquid chromatography in combination with tandem mass spectrometry has been used to analyze a variety of biological structures including protein complexes. Incorporating this approach with autosampling devices presents a number of problems including decreased sensitivity due to exposure to extra surfaces, carryover from run to run, and increased dead volume. We developed a device, termed Radial Column Array for Distribution and Automation (RCADiA), to automate multiple MuDPIT experiments while eliminating many of these problems and maintaining a high resolution and sensitive analysis. The design, which places each sample downstream of any common fluid path, presents a low risk of carryover between successive analyses. Beyond the convenience of automation, the RCADiA platform also produces data of similar quality to the standard method of performing individual MuDPIT experiments. We demonstrate this device by performing a comparative analysis of mitochondria enriched from rat liver and spinal cord. 相似文献
998.
The foundation for saliva-based diagnostics is the development of a complete catalog of secreted proteins detectable in saliva. Besides protein complexity, the greatest bioanalytical challenge facing comprehensive analysis of saliva samples is related to the large variation of protein relative abundances including the presence of high-abundance proteins such as amylases, mucins, proline-rich proteins (PRPs), and secretory IgA complex. Among a number of electrokinetic separation techniques, transient capillary isotachophoresis/capillary zone electrophoresis (CITP/CZE) specifically targets trace amounts of proteins and thus reduces the range of relative protein abundances for providing unparallel advantages toward the identification of low-abundance proteins. By employing a CITP/CZE-based multidimensional separation platform coupled with electrospray ionization-tandem mass spectrometry (ESI-tandem MS), a total of 6112 fully tryptic peptides are sequenced at a 1% false discovery rate (FDR), leading to the identification of 1479 distinct human SwissProt protein entries. By comparing with capillary isoelectric focusing (CIEF) as another electrokinetics-based stacking approach, CITP/CZE not only offers a broad field of application but also is less prone to protein/peptide precipitation during the analysis. The ultrahigh resolving power of CITP/CZE is evidenced by the large number of distinct peptide identifications measured from each CITP fraction together with the low peptide fraction overlapping among identified peptides. Furthermore, when evaluating the protein sequence coverage by the number of distinct peptides mapping to each protein identification, the CITP-based proteome technology similarly achieves the superior performance with 674 proteins (46%) having three or more distinct peptides, 288 (19%) having two distinct peptides, and 517 (35%) having a single distinct peptide. 相似文献
999.
Honig J Halpin J Browning D Crane J Hackel R Henesian M Peterson J Ravizza D Wennberg T Rieger H Marciante J 《Applied optics》2007,46(16):3269-3275
A diode-pumped injection-seeded Nd:YAG laser system with an average output power of 38 W is described. The laser operates at 300 Hz with pulse energies up to 130 mJ. The temporal pulse shape is nominally flat in time and the pulse width is user selectable from 350 to 600 ps. In addition, the spatial profile of the beam is near top hat with contrast <10%. 相似文献
1000.