The Effects of Sleep on the Acquisition of Skill

The current research was designed to evaluate the effect of sleep on memory for the declarative and procedural knowledge components of a cognitive skill. In a training phase, 17 participants in a no-sleep control group practised 120 repetitions of a simple algebra equation at Sam and 22 participants in a sleep group practised the task at 8pm. Novel task inputs were introduced withh1 the same task structure in a transfer phase conducted 12 hours after training for each group. Overnight sleep conferred a 29% performance deficit on the transfer tusk compared to no-sleep controls. The results support the hypothesis that sleep consolidates declarative and procedural knowledge components of an acquired cognitive skill. The prediction that, when consolidated by sleep, knowledge acquired in training creates processing overheads that disrupt post-sleep transfer when task inputs are changed at transfer was upheld. Discussion considered the influence at transfer of three cognitive phenomena: proactive interference, inhibition, and facilitation developed in training. A basis for parsing the relative discrete effects of these phenomena is advanced and a novel framework for predicting skill acquisition and transfer across various training and transfer conditions is outlined. The present study extends support to sleep-consolidation of complex declarative knowledge as well as procedural knowledge, and has implications for theories of memory system dissociation as well as theories of skill acquisition and transfer

Marketing Of Protected Areas As A Tool To Influence Visitors' Pre-Visit Decisions

As the result of the increasing influence of tourism, natural and protected area management is evolving from one primarily focused around onsite management and conservation to one that more broadly encompasses a greater range of holistic recreation and tourism experiences. In dealing with this evolution, national parks and protected area managers are now required to balance onsite interpretation activities with marketing and demand management activities

The Integrated Pre-visit Communication Audit: A User Guide

As a result of the increasing influence of tourism, natural and protected area management continues to evolve from management primarily focused around on-site management and conservation to one that more broadly encompasses a greater range of holistic recreation and tourism experiences. In dealing with this evolution national parks and protected area managers are now required to balance on-site interpretation activities with previsit marketing and demand management activities

Normative influence on retirement savings decisions: Do people care what employers and the government want?

The need for Australians to increase retirement savings has been widely promoted. Yet our understanding of the motivations of individuals to save at a higher rate remains sparse. This article reports the findings of a survey of superannuation fund members and their intentions to contribute more to superannuation and to manage their investment strategy. The article uses the theory of planned behaviour to focus on the important motivational influence of social norms. Formative research identified a number of influential social referents. Among identified referents, the study found that spouses appear to be the primary source of social influence for retirement savings decisions. The government and employers appear to exert little influence, and financial advisors and superannuation funds take up the middle ground of social influence. Possibilities for interventions designed to influence behaviour are discussed; however, conclusions are tempered by the fact that correspondence between intention and behaviour is not tested in the present research

Coherent manipulation of charge qubits in double quantum dots

The coherent time evolution of electrons in double quantum dots induced by fast bias-voltage switches is studied theoretically. As it was shown experimentally, such driven double quantum dots are potential devices for controlled manipulation of charge qubits. By numerically solving a quantum master equation we obtain the energy- and time-resolved electron transfer through the device which resembles the measured data. The observed oscillations are found to depend on the level offset of the two dots during the manipulation and, most surprisingly, also the on initialization stage. By means of an analytical expression, obtained from a large-bias model, we can understand the prominent features of these oscillations seen in both the experimental data and the numerical results. These findings strengthen the common interpretation in terms of a coherent transfer of electrons between the dots.Comment: 18 pages, 4 figure

Toward Coarse-Grained Elasticity of Single-Layer Covalent Organic Frameworks

Two-dimensional covalent organic frameworks (2D COFs) are an interesting class of 2D materials since their reticular synthesis allows the tailored design of structures and functionalities. For many of their applications, the mechanical stability and performance is an important aspect. Here, we use a computational approach involving a density-functional based tight-binding method to calculate the in-plane elastic properties of 45 COFs with a honeycomb lattice. Based on those calculations, we develop two coarse-grained descriptions: one based on a spring network and the second using a network of elastic beams. The models allow us to connect the COF force constants to the molecular force constants of the linker molecules and thus enable an efficient description of elastic deformations. To illustrate this aspect, we calculate the deformation energy of different COFs containing the equivalent of a Stone-Wales defect and find very good agreement with the coarse-grained description

Mechanical transmission of rotational motion between molecular-scale gears

Manipulating and coupling molecule gears is the first step towards realizing molecular-scale mechanical machines. Here, we theoretically investigate the behavior of such gears using molecular dynamics simulations. Within a nearly rigid-body approximation we reduce the dynamics of the gears to the rotational motion around the orientation vector. This allows us to study their behavior based on a few collective variables. Specifically, for a single hexa (4-tert-butylphenyl) benzene molecule we show that the rotational-angle dynamics corresponds to the one of a Brownian rotor. For two such coupled gears, we extract the effective interaction potential and find that it is strongly dependent on the center of mass distance. Finally, we study the collective motion of a train of gears. We demonstrate the existence of three different regimes depending on the magnitude of the driving-torque of the first gear: underdriving, driving and overdriving, which correspond, respectively, to no collective rotation, collective rotation and only single gear rotation. This behavior can be understood in terms of a simplified interaction potential

A bifunctional platinum(II) antitumor agent that forms DNA adducts with affinity for the estrogen receptor

A strategy is described for the re-design of DNA damaging platinum(II) complexes to afford elevated toxicity towards cancer cells expressing the estrogen receptor (ER). Two platinum-based toxicants are described in which a DNA damaging warhead, [Pt(en)Cl[subscript 2]] (en, ethylenediamine), is tethered to either of two functional groups. The first agent, [6-(2-amino-ethylamino)-hexyl]-carbamic acid 2-[6-(7α-estra-1,3,5,(10)-triene)-hexylamino]-ethyl ester platinum(II) dichloride ((Est-en)PtCl[subscript 2]), terminates in a ligand for the ER. The second agent is a control compound lacking the steroid; this compound, N-[6-(2-amino-ethylamino)-hexyl]-benzamide platinum(II) dichloride ((Bz-en)PtCl[subscript 2])), terminates in a benzamide moiety, which lacks affinity for the ER. Using a competitive binding assay, Est-en had 28% relative binding affinity (RBA) for the ER as compared to 17β-estradiol. After covalent binding to a synthetic DNA duplex 16-mer, the compound retained its affinity for the ER; specificity of the binding event was demonstrated by the ability of free 17β-estradiol as a competitor to disrupt the DNA adduct-ER complex. The (Est-en)PtCl[subscript 2] compound showed higher toxicity against the ER positive ovarian cancer cell line CAOV3 than did the control compound. (Est-en)PtCl[subscript 2] was also more toxic to the ER positive breast cancer line, MCF-7, than to an ER negative line, MDA-MB231.National Institutes of Health (U.S.) (Grant CA08661)Life Sciences Research Foundatio