193,441 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
(r,r)-disynephrine ether bis(hydrogen sulfate)
No full textThe asymmetric unit of the title compound [systematic name: (R, R)-2,4-bis(4-hydroxyphenyl)-N,N'-dimethyl-3-oxapentane-1,5- diammonium bis(hydrogen sulfate)], C18H26N2O32+center dot-2HSO(4)(-), contains one half-cation and one hydrogen sulfate anion. The cation has crystallographically imposed twofold symmetry with the rotation axis passing through the central ether O atom. Hydrogen bonds between the hydroxy group and amine H atoms of the cation to two hydrogen sulfate anions link the three ions in a ring motif. A three-dimensional network is accomplished by additional O-H center dot center dot center dot O hydrogen bonds between the anions and by N-H center dot center dot center dot O hydrogen bonds between the cations. Disorder with equally occupied sites affects the H-atom position in the anio
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Highly efficient separation of actinides from lanthanides by a phenanthroline-derived bis-triazine ligand
No full textThe synthesis, lanthanide complexation, and solvent ex- traction of actinide(III) and lanthanide(III) radiotracers from nitric acid solutions by a phenanthroline-derived quadridentate bis-triazine ligand are described. The ligand separates Am(III) and Cm(III) from the lanthanides with remarkably high efficiency, high selectivity, and fast extraction kinetics compared to its 2,2'-bipyridine counterpart. Structures of the 1:2 bis-complexes of the ligand with Eu(III) and Yb(III) were elucidated by X-ray crystallography and force field calculations, respec-tively. The Eu(III) bis-complex is the first 1:2 bis-complex of a quadridentate bis-triazine ligand to be characterized by crystallography. The faster rates of extraction were verified by kinetics measurements using the rotating membrane cell technique in several diluents. The improved kinetics of metal ion extraction are related to the higher surface activity of the ligand at the phase interface. The improvement in the ligand's properties on replacing the bipyridine unit with a phenanthroline unit far exceeds what was anticipated based on ligand design alone
Conformational dependence of through-space tellurium-tellurium spin-spin coupling in peri-substituted bis(tellurides)
No full textThe work in this project was supported by the Engineering and Physical Sciences Research Council (EPSRC). M.B. wishes to thank EaStCHEM and the University of St Andrews for support.Three related series of peri‐substituted bis(tellurides) bearing naphthalene, acenaphthene and acenaphthylene backbones (Nap/Acenap/Aceyl(TeY)2 (Nap=naphthalene‐1,8‐diyl N ; Acenap=acenaphthene‐5,6‐diyl A ; Aceyl=acenaphthylene‐5,6‐diyl Ay ; Y=Ph 1 ; Fp 2 ; Tol 3 ; An‐p 4 ; An‐o 5 ; Tp 6 ; Mes 7 ; Tip 8 ) have been synthesised and their solid‐state structures determined by X‐ray crystallography. Molecular conformations were classified as a function of the two C9‐C‐Te‐C(Y) dihedral angles (θ); in the solid all members adopt AB or CCt configurations, with larger Te(aryl) moieties exclusively imposing the CCt variant. Exceptionally large J(125Te,125Te) spin–spin coupling constants between 3289–3848 Hz were obtained for compounds substituted by bulky Te(aryl) groups, implying these species are locked in a CCt‐type conformation. In contrast, compounds incorporating smaller Te(aryl) moieties are predicted to be rather dynamic in solution and afford much smaller J values (2050–2676 Hz), characteristic of greater populations of AB conformers with lower couplings. This conformational dependence of through‐space coupling is supported by DFT calculations.Peer reviewe
An evaluation of the relationship between Gray’s revised RST and Eysenck’s PEN: distinguishing BIS and FFFS in Carver and White’s BIS/BAS scales
No full textRecent revisions of Gray's Reinforcement Sensitivity Theory (RST) have important implications for self-report measures of approach and avoidance behaviours and how Gray's model relates to other personality models. In this paper, we examine the revised RST by comparing Carver and White's (1994) original one-factor solution of the BIS scale with two alternative two-factor solutions separating BIS-Anxiety and FFFS-Fear. We also examine the relationships between Eysenck's PEN and revised RST factors. Two hundred and twelve participants completed Carver and White's BIS/BAS scales and Eysenck's Personality Questionnaire-Revised. Confirmatory factor analyses of the original BIS scale showed that the hypothesized two-factor model of BIS-Anxiety and FFFS-Fear was the best fit to these data. Associations between the revised RST and Eysenck's PEN were examined using path analysis. In line with theoretical predictions, Psychoticism was related to revised BIS-Anxiety and BAS, Neuroticism to revised BIS-Anxiety and FFFS- Fear, and Extraversion to BAS and FFFS-Fear. Distinctions between BAS subscales and their associations to BIS, N and P were made in terms of past, present and future focus. Possible explanations for mixed findings in the literature and implications for future research are discussed
Bis-Catecholate, Bis-Dithiocatecholate, and Tetraalkoxy Diborane(4) Compounds: Aspects of Synthesis and Electronic Structure
No full textThe synthesis and characterization of a series of bis-catecholate diborane(4) compounds, B2(1,2-O2C6H4)2 (3),
B2(1,2-O2-3-MeC6H3)2 (6), B2(1,2-O2-4-MeC6H3)2 (7), B2(1,2-O2-4-ButC6H3)2 (8), B2(1,2-O2-3,5-But2C6H2)2 (9),
B2(1,2-O2-3-MeOC6H3)2 (10), bis-dithiocatecholate diborane(4) compounds, B2(1,2-S2C6H4)2 (13), B2(1,2-S2-4-MeC6H3)2 (14), and tetraalkoxy diborane(4) compounds, B2(OCH2CMe2CH2O)2 (11) and B2(OCMe2CMe2O)2
(12) from B2(NMe2)4 (1) is described, as are the bis(NHMe2) adducts of 3 and 9, namely [B2(1,2-O2C6H4)2(NHMe2)2] (4) and [B2(1,2-O2-3,5-But2C6H2)2(NHMe2)2] (5). The latter two compounds are intermediates in the
formation of 3 and 9 from 1. Compound 1 is synthesized by reductive coupling of BCl(NMe2)2, which in turn
is prepared from reaction of BCl3 with B(NMe2)3 in a 1:2 stoichiometry. We have also characterized [B2Cl4(NHMe2)2] (15) formed from addition of HCl to 1 prior to complete reaction with diols, and the salt, [NH2Me2][B(1,2-O2C6H4)2] (16), which arises from addition of catechol to B(NMe2)3. Thus, any B(NMe2)3 impurity present
after the preparation of 1 needs to be removed by distillation prior to reaction with alcohols. The dimer, [BCl2(μ-NMe2)]2 (17) has also been characterized. This is formed from reaction of BCl3 with B(NMe2)3 if a 2:1 rather
than 1:2 stoichiometry is used. Photoelectron spectra of 1, 3, 8, 11, and 12 are reported along with those of the
corresponding diols, catechol, 4-But-catechol, 2,2-dimethyl-1,3-propanediol, and pinacol. The ionization energies
of the B2(OR)4 compounds follow the series 8 3 12 11. Replacement of O for N in the B2N4 framework
increases the IE by ca. 1.65 eV, whereas the presence of an aromatic ring rather than an aliphatic chain decreases
the IE by ca. 1.50 eV. The presence of electron donating But-groups also decreases the IE
Pragmatic Case Studies as a Source of Unity in Applied Psychology
No full textTo unify or not to unify applied psychology: that is the question. In this article we review pendulum swings in the historical efforts to answer this question—from a comprehensive, positivist, “top-down,” deductive yes between the 1930s and the early 60s, to a postmodern no since then. A rationale and proposal for a limited, “bottom-up,” inductive yes in applied psychology is then presented, employing a case-based paradigm that integrates both positivist and postmodern themes and components. This paradigm is labeled “pragmatic psychology” and, its specific use of case studies, the “Pragmatic Case Study Method” (“PCS Method”). We call for the creation of peer-reviewed journal-databases of pragmatic case studies as a foundational source of unifying applied knowledge in our discipline. As one example, the potential of the PCS Method for unifying different angles of theoretical regard is illustrated in an area of applied psychology, psychotherapy, via the case of Mrs. B. The article then turns to the broader historical and epistemological arguments for the unifying nature of the PCS Method in both applied and basic psychology.Peer reviewe
Dr. Edwin Wright Collection: Author Unknown
No full textNotes - The author relates several short stories about his neighbours including Alex McDonell, homesteading and life around Meanook and Athabasca (1 page
Total synthesis of (+/-)-4,5-Bis-epi-neovibsanin A and B: A neurite outgrowth comparison study
No full textImage Presented (±)-4,5-Bis-epi-neovibsanin A and B were synthesized in 12 steps. The acid-catalyzed, one-pot, five-step cascade reaction was central toward the formation of the tricyclic core. The two diastereomers of natural neovibsanin A and B acted as desirable derivatives for structure-activity relationship studies to probe neurotrophic activity. Both (±)-4,5-bis-epi-neovibsanin A and B strongly potentiate neurite outgrowth in NGF-stimulated PC12 cells. Furthermore, the tricyclic core appears to be largely responsible for promoting a biological response
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