8,616 research outputs found
The first experimental flight package of an advanced telemetry system with adaptive capability Technical summary report, 1 Jul. 1963 - 15 Feb. 1965
Mechanical design, and environmental and functional testing of advanced telemetry system flight package with adaptive capabilit
Synergies between processing and memory in children's reading span.
Previous research has established the relevance of working memory for cognitive development. Yet the factors responsible for shaping performance in the complex span tasks used to assess working memory capacity are not fully understood. We report a study of reading span in 7- to 11-year old children that addresses several contemporary theoretical issues. We demonstrate that both the timing and the accuracy of recall are affected by the presence or absence of a semantic connection between the processing requirement and the memoranda. Evidence that there can be synergies between processing and memory argues against the view that complex span simply measures the competition between these activities. We also demonstrate a consistent relationship between the rate of completing processing operations (sentence reading) and recall accuracy. At the same time, the shape and strength of this function varies with the task configuration. Taken together, these results demonstrate the potential for reconstructive influences to shape working memory performance among children
With development, list recall includes more chunks, not just larger ones.
The nature of the childhood development of immediate recall has been difficult to determine. There could be a developmental increase in either the number of chunks held in working memory or the use of grouping to make the most of a constant capacity. In 3 experiments with children in the early elementary school years and adults, we show that improvements in the immediate recall of word and picture lists come partly from increases in the number of chunks of items retained in memory. This finding was based on a distinction between access to a studied group of items (i.e., recall of at least 1 item from the group) and completion of the accessed group (i.e., the proportion of the items recalled from the group). Access rates increased with age, even with statistical controls for completion rates, implicating development of capacity in chunks. (PsycINFO Database Record (c) 2010 APA, all rights reserved
Mononuclear Transition Metal Complexes of 7-Nitro-1,3,5-Triazaadamantane
This is the peer reviewed version of the following article: Wagner, G., Horton, P. N., & Coles, S. J. (2016). Mononuclear Transition Metal Complexes of 7-Nitro-1,3,5-Triazaadamantane. ChemistrySelect, 1(8), 1548-1555. DOI: 10.1002/slct.201600502, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/slct.201600502/abstract. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingComplexes of the type [MCl2(7-nitro-1,3,5-triaza-adamantane)2] (M = Zn(II), Pd(II), Pt(II)) and [MCl2(H2O)2(7-nitro-1,3,5-triazaadamantane) 2] (M = Mn (II), Co(II), Ni(II)) have been prepared and their structures have been analysed by X-ray crystallography, elemental analysis, IR and solid state 13C and 15N NMR spectroscopy, supported by density functional theory/ gauge independent atomic orbital (DFT/GIAO) calculations. In each case, 7-nitro-1,3,5-triazaadamantane acts as a mono-dentate ligand and binds to one metal centre only, in spite of the presence of three equivalent amino nitrogens. In the Co(II) and Ni(II) complexes, a two-dimensional intermolecular hydrogen bonding network between the aqua- and the chloro ligands is established. The uncoordinated amines of the 7-nitro-1,3,5-triaza- adamantane are not involved in any H-bonding, as a result of the exceptionally low basicity of this compound
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To boldly go… the librarian's role in text and data mining
The relatively new exception to copyright law that we enjoy in the UK, permitting text and data mining (TDM) for the purposes of non-commercial research, offers potential to further knowledge and make scientific and medical breakthroughs. Importantly, the new exception states that any contractual clause which purports to restrict this exception is automatically null and void. Librarians who manage electronic resources and datasets can assist researchers greatly. However, in order to do this they need a robust understanding of the law and to be assertive in their Ârelationships with publishers when negotiating or interpreting licence agreements. This article examines the ways in which librarians can facilitate the work of researchers who want to use TDM. It also argues that librarians need to encourage researchers to exploit the new copyright exceptions as key partners in the research process
Programmable synthesis of organic cages with reduced symmetry
Integrating symmetry-reducing methods into self-assembly methodology is desirable to efficiently realise the full potential of molecular cages as hosts and catalysts. Although techniques have been explored for metal organic (coordination) cages, rational strategies to develop low symmetry organic cages remain limited. In this article, we describe rules to program the shape and symmetry of organic cage cavities by designing edge pieces that bias the orientation of the amide linkages. We apply the rules to synthesise cages with well-defined cavities, supported by evidence from crystallography, spectroscopy and modelling. Access to low-symmetry, self-assembled organic cages such as those presented, will widen the current bottleneck preventing study of organic enzyme mimics, and provide synthetic tools for novel functional material design
Oxidoborates templated by cationic nickel(II) complexes and self-assembled from B(OH)3
Several oxidoborates, self-assembled from B(OH)3 and templated by cationic Ni(II) coordination compounds, were synthesized by crystallization from aqueous solution. These include the ionic compounds trans-[Ni(NH3)4(H2O)2][B4O5(OH)4].H2O (1), s-[Ni(dien)2][B5O6(OH)4]2 (dien = N-(2-aminoethyl)-1,2-ethanediamine (2), trans-[Ni(dmen)2(H2O)2] [B5O6(OH)4]2.2H2O (dmen = N,N-dimethyl-1,2-diaminoethane) (3), [Ni(HEen)2][B5O6(OH)4]2 (HEen = N-(2-hydroxyethyl)-1,2-diaminoethane) (4), [Ni(AEN)][B5O6(OH)4].H2O (AEN = 1-(3-azapropyl) -2,4-dimethyl-1,5,8-triazaocta-2,4-dienato(1-)) (5), trans-[Ni(dach)2(H2O)2][Ni(dach)2] [B7O9(OH)5]2.4H2O (dach = 1,2-diaminocyclohexane) (6), and the neutral species trans-[Ni(en)(H2O)2{B6O7(OH)6}].H2O (7) (en = 1,2-diaminoethane), and [Ni(dmen)(H2O){B6O7(OH)6}].5H2O (8). Compounds 1–8 were characterized by single-crystal XRD studies and by IR spectroscopy and 2, 4–7 were also characterized by thermal (TGA/DSC) methods and powder XDR studies. The solid-state structures of all compounds show extensive stabilizing H-bond interactions, important for their formation, and also display a range of gross structural features: 1 has an insular tetraborate(2-) anion, 2–5 have insular pentaborate(1-) anions, 6 has an insular heptaborate(2-) anion (‘O+’ isomer), whilst 7 and 8 have hexaborate(2-) anions directly coordinated to their Ni(II) centers, as bidentate or tridentate ligands, respectively. The Ni(II) centers are either octahedral (1–4, 7, 8) or square-planar (5), and compound 6 has both octahedral and square-planar metal geometries present within the structure as a double salt. Magnetic susceptibility measurements were undertaken on all compounds.</p
State of the World's Volunteerism Report: Universal Values for Global Well-being
The focus of this report is on the universal values that motivate people the world over to volunteer for the common good and on the impact of volunteer action on societies and individuals. The authors advocate the power of volunteering to promote cooperation, encourage participation and contribute to the well-being of individuals and of society as a whole
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