32,966 research outputs found
Retrieval of episodic versus generic information: Does the order of recall affect the amount and accuracy of details reported by children about repeated events?
Children (N = 157) 4- to 8-years old participated 1 (single) or 4 times (repeated) in an interactive event. Across each condition, half were questioned a week later about the only or a specific occurrence of the event (Depth-first), and then about what usually happens. Half were prompted in the reverse order (Breadth-first). Children with repeated experience who first were asked about what usually happens reported more event-related information overall than those asked about an occurrence first. All children used episodic language when describing an occurrence; however children with repeated-event experience used episodic language less often when describing what usually happens than did those with single experience. Accuracy rates did not differ between conditions. Implications for theories of repeated-event memory are discussed
Geometrical frustration in the spin liquid beta'-Me3EtSb[Pd(dmit)2]2 and the valence bond solid Me3EtP[Pd(dmit)2]2
We show that the electronic structures of the title compounds predicted by
density functional theory (DFT) are well described by tight binding models. We
determine the frustration ratio, J'/J, of the Heisenberg model on the
anisotropic triangular lattice, which describes the spin degrees of freedom in
the Mott insulating phase for a range of Pd(dmit)2 salts. All of the
antiferromagnetic materials studied have J'/J 0.9, consistent
with predictions for the Heisenberg model. All salts with 0.5 < J'/J < 0.9,
where many-body theories find a number of competing ground states, are known,
experimentally, to be charge ordered, valence bond solids or spin liquids.Comment: Accepted for publication in Phys. Rev. Lett. 4+11 pages, 3+15
figures, major rewrite, added calculations of Hubbard
Incorporation of cytochrome oxidase into cardiolipin bilayers and induction of nonlamellar phases.
Cytochrome oxidase from beef heart has been lipid-substituted with beef heart cardiolipin. The lipid phase behavior and protein aggregation state of the reconstituted complexes have been studied with 31P NMR, freeze-fracture electron microscopy, and saturation-transfer ESR of the spin-labeled protein. In the absence of salt, the lipid has a lamellar arrangement, and the protein is integrated and uniformly distributed in the membrane vesicles and undergoes rapid rotational diffusion. The presence of the protein stabilizes the cardiolipin lamellar phase against salt-induced transitions to the inverted hexagonal phase. The threshold salt concentration becomes higher and the extent of conversion becomes lower with decreasing lipid:protein ratio. In high salt, lamellar-phase lipid with integrated protein coexists with hexagonal-phase lipid free of protein, and the rotational diffusion of the protein is drastically reduced as a result of the high packing density
Selection of sampling rate for digital control of aircrafts
The considerations in selecting the sample rates for digital control of aircrafts are identified and evaluated using the optimal discrete method. A high performance aircraft model which includes a bending mode and wind gusts was studied. The following factors which influence the selection of the sampling rates were identified: (1) the time and roughness response to control inputs; (2) the response to external disturbances; and (3) the sensitivity to variations of parameters. It was found that the time response to a control input and the response to external disturbances limit the selection of the sampling rate. The optimal discrete regulator, the steady state Kalman filter, and the mean response to external disturbances are calculated
Public Choice and the Economic Analysis of Anarchy: A Survey
Public choice economists began studying the economics of anarchy in the 1970s. Since then, the amount of research on anarchy has burgeoned. This article surveys the important public choice contributions to the economics of anarchy. Following the lead of the early public choice economists, many current economists are researching and analyzing how individuals interact without government. From their non-public-interested explanations of the creation of government law enforcement to their historical studies of attempts to internalize externalities under anarchy, public choice scholars are arriving at a more realistic perspective on government and how people interact when government law enforcement is lacking. Although the economics of politics often receives more attention, the economics of anarchy is an important area of research in public choice.Anarchism; Lawlessness; Order; Internalization of Externalities; Self-Governance
A note on the use of FTA™ technology for storage of blood samples for DNA analysis and removal of PCR inhibitors
peer-reviewedFTA™ technology is widely used across many molecular disciplines for sample
capture, storage and analysis. The use of this technology for the long-term storage
of blood samples for DNA analysis was examined as well as its potential to remove
inhibitors from DNA samples previously extracted from blood with PCR inhibitors
remaining. It was found that blood spots stored on FTA™ cards for 8 years at
room temperature gave successful PCR products and that FTA™ cards are a useful
tool for removing substances in samples which interfere with or inhibit, the PCR
reaction
Children’s ability to recall unique aspects of one occurrence of a repeated event
Preschool and school-age children’s memory and source monitoring were investigated by questioning them about one occurrence of a repeated lab event (n = 39). Each of the four occurrences had the same structure, but with varying alternatives for the specific activities and items presented. Variable details had a different alternative each time; hi/lo details presented the identical alternative three times and changed once. New details were present in one occurrence only and thus had no alternatives. Children more often confused variable, lo, and new details across occurrences than hi details. The 4- to 5-year-oldchildren were less accurate than 7- to 8-year-old children at attributing details to the correct occurrence when specifically asked. Younger children rarely recalled new details spontaneously, whereas 50% of the older children did and were above chance at attributing them to their correct occurrence. Results are discussed with reference to script theory, fuzzy-trace theory and the source-monitoring framework
Investigation of Prolific Sheep from UK and Ireland for Evidence on Origin of the Mutations in BMP15 (FecXG, FecXB) and GDF9 (FecGH) in Belclare and Cambridge Sheep
peer-reviewedThis paper concerns the likely origin of three mutations with large effects on ovulation rate identified in the Belclare and Cambridge sheep breeds; two in the BMP15 gene (FecXG and FecXB) and the third (FecGH) in GDF9. All three mutations segregate in Belclare sheep while one, FecXB, has not been found in the Cambridge. Both Belclare and Cambridge breeds are relatively recently developed composites that have common ancestry through the use of genetic material from the Finnish Landrace and Lleyn breeds. The development of both composites also involved major contributions from exceptionally prolific ewes screened from flocks in Ireland (Belclare) and Britain (Cambridge) during the 1960s. The objective of the current study was to establish the likely origin of the mutations (FecXG, FecXB and FecGH) through analysis of DNA from Finnish Landrace and Lleyn sheep, and Galway and Texel breeds which contributed to the development of the Belclare breed. Ewes with exceptionally high prolificacy (hyper-prolific ewes) in current flocks on Irish farms were identified to simulate the screening of ewes from Irish flocks in the 1960s. DNA was obtained from: prolific ewes in extant flocks of Lleyn sheep (n = 44) on the Lleyn peninsula in Wales; hyper-prolific ewes (n = 41); prolific Galway (n = 41) ewes; Finnish Landrace (n = 124) and Texel (n = 19) ewes. The FecXG mutation was identified in Lleyn but not in Finnish Landrace, Galway or Texel sheep; FecXB was only found among the hyper-prolific ewes. The FecGH mutation was identified in the sample of Lleyn sheep. It was concluded from these findings that the Lleyn breed was the most likely source of the FecXG and FecGH mutations in Belclare and Cambridge sheep and that the FecXB mutation came from the High Fertility line that was developed using prolific ewes selected from commercial flocks in Ireland in the 1960′s and subsequently used in the genesis of the Belclare.Financial support through the Teagasc Walsh Fellowship Scheme, Genesis Faraday SPARK award (Lleyn survey) and Science Foundation Ireland (07/SRC/B1156) is gratefully acknowledged
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