bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Lithium‐Containing Pnictides with 1‐D Infinite Chains of Supertetrahedral Clusters: Synthesis, Crystal and Electronic Structure of Ba4Li2Cd3Pn6 (Pn = P, As and Sb)
Authors: Makongo Julien P. A. , You Tae‐Soo , He Hua , Suen Nian‐Tzu , Bobev Svilen 
Published: August 2014

AbstractThe novel complex pnictides Ba4Li2Cd3Pn6 (Pn = P, As and Sb) have been synthesized by direct combination of the respective elements at high temperature, and structurally characterized by single‐crystal X‐ray diffraction. The three isostructural compounds crystallize with their own structure type in the centrosymmetric orthorhombic space group Cmcm (Pearson code oC60). The crystal structure is based on one‐dimensional infinite chains of supertetrahedral clusters, [Cd4Pn10], running parallel the a‐axis. These chains are connected through Pn2‐type dumbbells. Tight‐binding electronic structure calculations show that the electronic stability of these compounds requires strong covalent Pn–Pn and Cd–Pn bonds. The interactions within the polyanionic sub‐structure are complimented by weaker Ba–Pn and Li–Pn bonds, which also show a substantial degree of covalency, and the strength of all interactions correlates very well with the corresponding interatomic distances. The precise satisfaction of the valence rules and the Zintl–Klemm concept is not essential though as structural vacancies on Cd and Li sites bring about an interplay between ionicity and covalency among the electronegative components. Electronic structure calculations show that Ba4Li2Cd3P6 is expected to be a semiconductor with a band gap of ca. 0.5 eV, while the gap decreases and vanishes altogether for the As‐ and Sb‐analogs, respectively. Solid solutions between arsenides and antimonides appear possible, which could be an effective way to fine‐tune transport properties. Since the latter two compounds can be considered as moderately‐to‐heavily doped intrinsic semiconductors, these materials might be suitable candidates for thermoelectric applications.
Main‐Chain Oligomers from NiII‐ and CuII‐Centered Unsymmetrical N2O2 Schiff‐Base Complexes: Synthesis and Spectral, Structural, and Second‐Order Nonlinear Optical Properties
Authors: Celedón Salvador , Dorcet Vincent , Roisnel Thierry , Singh Anu , Ledoux‐Rak Isabelle , Hamon Jean‐René , Carrillo David , Manzur Carolina 
Published: August 2014

AbstractOligomeric main‐chain Schiff‐base compounds 4 and 5 have been synthesized by the trans‐esterification of their respective doubly functionalized monomeric precursors [M{(η5‐C5H5)Fe(η5‐C5H4)C(=O)CH=C(4‐C6H4OH)NCH2CH2N=CH‐(2‐O,4‐CO2H–C6H3)}] [M = Ni (2), Cu (3)] in dmf. The new compounds were characterized by elemental analysis, FTIR and multidimensional NMR spectroscopy, mass spectrometry, and cyclic voltammetry. Compounds 2, 3, and 6, the corresponding amide of 2, were characterized by X‐ray structural investigation. Gel permeation chromatography established that oligomers 4 and 5 are formed of approximately six monomeric units, and differential scanning calorimetry and thermal gravimetric analysis indicated that they are thermally stable with decomposition temperatures exceeding 230 °C. Harmonic light scattering measurements showed that compounds 2–5 exhibit rather high second‐order nonlinear responses, between 224 × 10–30 and 399 × 10–30 esu, with hyperpolarizability β1.91 values that increase significantly on passing from the monomeric to the oligomeric species.
Mechanistic Insights into the PdII‐Catalyzed Chemoselective N‐Demethylation vs. Cyclometalation Reactivity Pathways in 1‐Aryl‐N,N‐dimethylethanamines
Authors: Yap Jeanette See Leng , Ding Yi , Yang Xiang‐Yuan , Wong Jonathan , Li Yongxin , Pullarkat Sumod A. , Leung Pak‐Hing 
Published: August 2014

AbstractTwo structurally isomeric substituted N,N‐dimethylethanamines have been prepared. Treatment of the 2,4‐di‐tert‐butylphenyl isomer with PdII ions generated the ortho‐metalated complexes. On the other hand, treatment of the 2,5‐di‐tert‐butylphenyl‐substituted amine resulted in the unexpected chemoselective cleavage of one of the three N–C bonds, thus generating the corresponding secondary amine. The N‐demethylation process could be catalyzed at room temperature by palladium(II) catalysts such as PdCl2 or Pd(OAc)2. Furthermore, treatment with a stoichiometric amount of PdII ions gave a metal complex in which both secondary amines were bound to Pd in an N‐monodentate fashion. When triethylamine was introduced, one of the N‐ethyl groups in NEt3 was cleaved, and an unexpected heteroamine complex was produced. The products generated were isolated and characterized by X‐ray crystallography. Mechanistic insights into the cyclometalation and C–N cleavage observed are discussed.
Very long chain omega‐3 (n‐3) fatty acids and human health
Authors: Calder Philip C. 
Published: August 2014

Omega‐3 (n‐3) fatty acids are a family of polyunsaturated fatty acids that contribute to human health and well‐being. Functionally the most important n‐3 fatty acids appear to be eicosapentaenoic acid (EPA) and docosahexaenoioc acid (DHA), but roles for n‐3 docosapentaenoic acid (DPA) are now emerging. Intakes of EPA and DHA are usually low, typically below recommended intakes. Increased intakes are reflected in greater incorporation into blood lipid, cell and tissue pools. Increased content of EPA and DHA modifies the structure of cell membranes and the function of membrane proteins involved as receptors, signaling proteins, transporters, and enzymes. EPA and DHA modify the production of lipid mediators and through effects on cell signaling can alter patterns of gene expression. Through these actions EPA and DHA alter cell and tissue responsiveness in a manner that seems to result in more optimal conditions for growth, development, and maintenance of health. The effects of n‐3 fatty acids are evident right through the life course, meaning that there is a need for all sectors of the population to have a sufficient intake of these important nutrients. EPA and DHA have a wide range of physiological roles which are linked to certain health or clinical benefits.Practical application: Very long chain omega‐3 (n‐3) fatty acids are found in seafood, especially fatty fish, and in supplements. They exert a range of health benefits as a result of their molecular, cellular and physiological actions. Consequently, very long chain n‐3 fatty acids play important roles in growth, development, optimal function, and maintenance of health and well‐being right across the life course. Therefore, all sectors of the population need to ensure sufficient intake of these important nutrients. This can be achieved through eating fatty fish or, failing that, use of good quality supplements.General overview of the mechanisms by which very long chain n‐3 fatty acids can influence the function of cells.
Mild, Stereoselective, and Highly Efficient Synthesis of N‐Acylhydrazones Mediated by CeCl3·7H2O in a Broad Range of Solvents
Authors: dos Santos Filho José Maurício 
Published: August 2014

AbstractIn a mild and practical approach, hydrazides and aldehydes underwent condensation reactions that were mediated by cerium(III) chloride to be rapidly converted into N‐acylhydrazones. This method uses a minimal catalytic amount of cerium(III), is stereoselective, and offers several unique features, such as compatibility with aryl, heterocyclic, alkenyl, and sensitive functional groups as well as the ability to prepare N‐acylhydrazones from highly hindered substrates. More strikingly, cerium(III) efficiently mediated the reaction with less reactive substrates such as diaryl and alkyl aryl ketones, when classical protocols without the catalyst were not effective. This method enables the synthesis of a structurally diverse library of N‐acylhydrazones that have applications in synthetic and medicinal chemistry.
Two‐Step Regioselective Synthesis of 3‐(Sulfonylamino)imidazo[1,2‐a]pyrimidines from 2‐Aminopyrimidines and N‐(2,2‐Dichloro‐2‐phenylethylidene)arensulfonamides
Authors: Rozentsveig Igor B. , Serykh Valery Yu. , Chernysheva Gulnur N. , Kondrashov Evgeniy V. , Fedotova Alena I. , Ushakov Igor A. , Tretyakov Evgeny V. , Romanenko Galina V. 
Published: August 2014

AbstractThe reaction of 2‐aminopyrimidines with N‐(2,2‐dichloro‐2‐phenylethylidene)arenesulfonamides affords the corresponding products of nucleophilic addition to the azomethine group, N‐[2,2‐dichloro‐2‐phenyl‐1‐(heterylamino)ethyl]sulfonamides, in good yields. The latter are easily cyclized to give imidazo[1,2‐a]pyrimidin‐3‐ylsulfonamides in the presence of NaOH, whereas the expected isomeric imidazo[1,2‐a]pyrimidin‐2‐ylsulfonamides are not formed. A tentative mechanism for the formation of annulated heterocyclic derivatives through Dimroth rearrangement has been proposed.
Stereoselective Synthesis of Tricyclic Diproline Analogues that Mimic a PPII Helix: Structural Consequences of Ring‐Size Variation
Authors: Soicke Arne , Reuter Cédric , Winter Matthias , Neudörfl Jörg‐Martin , Schlörer Nils , Kühne Ronald , Schmalz Hans‐Günther 
Published: August 2014

AbstractPolycyclic proline‐derived scaffolds (ProMs) have recently demonstrated their value as conformationally defined dipeptide analogs for the modular construction of secondary structure mimetics, specifically interfering with PPII helix‐mediated protein–protein interactions. We disclose the stereoselective synthesis of two new tricyclic amino acid scaffolds (ProM‐4 and ProM‐8) that differ from the first generation scaffold ProM‐1 by the size of ring A. Conformational preferences and subtle structural differences of the three homologous scaffolds were analyzed by X‐ray crystallography, computational calculations, and NMR spectroscopy. N‐tert‐butoxycarbonyl(Boc)‐3‐(1‐propenyl)azetidine‐2‐carboxylic acid was prepared from L‐aspartic acid through β‐lactam intermediates. The corresponding piperidine‐based building block rac‐N‐Boc‐3‐vinylpipecolic acid was synthesized by Cu‐catalyzed 1,4‐addition of vinyl‐MgBr to methyl N‐Boc‐2,3‐dehydropipecolate. Target molecules were prepared through peptide coupling of the respective ring A building blocks with cis‐5‐vinylproline tert‐butyl ester and subsequent ring‐closing metathesis. Selective deprotection of a tert‐butyl carbamate (N‐Boc protecting group) in the presence of a tert‐butyl ester was achieved with trifluoroacetic acid at 0 °C.
Mild closed head injury promotes a selective trigeminal hypernociception: Implications for the acute emergence of post‐traumatic headache
Authors: Benromano T. , Defrin R. , Ahn A.H. , Zhao J. , Pick C.G. , Levy D. 
Published: August 2014

AbstractBackgroundHeadache is one of the most common symptoms following traumatic head injury. The mechanisms underlying the emergence of such post‐traumatic headache (PTH) remain unknown but may be related to injury of deep cranial tissues or damage to central pain processing pathways, as a result of brain injury.MethodsA mild closed head injury in mice combined with the administration of cranial or hindpaw formalin tests was used to examine post‐traumatic changes in the nociceptive processing from deep cranial tissues or the hindpaw. Histological analysis was used to examine post‐traumatic pro‐inflammatory changes in the calvarial periosteum, a deep cranial tissue.ResultsAt 48 h after head injury, mice demonstrated enhanced nociceptive responses following injection of formalin into the calvarial periosteum, a deep cranial tissue, but no facilitation of the nociceptive responses following injection of formalin into an extracranial tissue, the hindpaw. Mice also showed an increase in the number of activated periosteal mast cells 48 h following mild head trauma, suggesting an inflammatory response.ConclusionOur study demonstrates that mild closed head injury is associated with enhanced processing of nociceptive information emanating from trigeminal‐innervated deep cranial tissues, but not from non‐cranial tissues. Based on these finding as well as the demonstration of head injury‐evoked degranulation of calvarial periosteal mast cells, we propose that inflammatory‐evoked enhancement of peripheral cranial nociception, rather than changes in supraspinal pain mechanisms play a role in the initial emergence of PTH. Peripheral targeting of nociceptors that innervate the calvaria may be used to ameliorate PTH pain.
The association between inhibition and pain tolerance in the elderly: Evidence from event‐related potentials
Authors: Zhou S. , Kemp J. , Després O. , Pebayle T. , Dufour A. 
Published: August 2014

AbstractBackgroundAge‐related alterations in both pain perception and inhibitory functions have been observed, but the relationship between the two in older adults remains unclear. Previous studies were mainly based on behavioural measures which do not allow assessment of underlying neural mechanisms.MethodsThe present study evaluated the association between inhibition and pain perception in 26 healthy elderly volunteers. Cognitive inhibition was assessed by Stroop interference tests and response inhibition by a Go/No‐go task. Event‐related potentials during the Go/No‐go task were recorded to provide brain activity data. Pain perception was assessed with the cold pressor test, in which subjects were asked to resist pain as long as possible. The exposure time (ET), intensity of tolerated pain and unpleasantness were interpreted as psychophysiological outcomes of pain.ResultsWe observed that better performance on cognitive inhibition, assessed by Stroop interference tasks, was correlated with higher intensity of tolerated pain. Greater brain activity during response inhibition, evaluated as larger amplitude (P3), and shorter latency (N2) to a No‐go stimuli were correlated with longer ET‐pain tolerance.ConclusionsIn the healthy elderly, the neuronal circuits of cognitive inhibition and conscious pain control may overlap, and brain regions engaged in response inhibition may be more involved in behavioural response of pain.
Supporting the Spread of Systems Engineering in Healthcare: A Partnership for Teaching Patient Safety Residents
Authors: Rust Tom , Archambeault Cliona , Triplett Stephanie , Kim Bo , Kartha Anand 
Published: August 2014

AbstractRecent reports indicate that physician graduates do not possess an understanding of systems engineering tools. This is relevant because systems failures in healthcare delivery generate medical errors and avoidable adverse events, causing hundreds of thousands of deaths and wasting billions of dollars annually. The Institute of Medicine calls for collaboration across disciplines to spread systems engineering within healthcare; however, few physician educators possess the necessary expertise to teach these methods. In this article, we describe a novel systems engineering and quality improvement training partnership between engineers and practicing clinicians. This curriculum effectively increased knowledge in systems thinking, provided direct experience utilizing improvement tools, and enhanced care delivery. Through coupling the interests and resources of engineering faculty and the residency training program, we were able to build an effective training program that empowers front‐line staff to identify and act on systems‐based patient safety problems.
Educational Apps: Using Mobile Applications to Enhance Student Learning of Statistical Concepts
Authors: Ling Chen , Harnish Drew , Shehab Randa 
Published: August 2014

AbstractThis research sought to understand whether the use of mobile applications (e.g., iPhone apps) had an impact on students’ learning of new statistical concepts. A control group (n = 12) was compared against a group that used a statistical mobile app (n = 13) during a simulated statistics lecture on the topic of normal distribution. Students received a classroom lecture followed by a period of either pencil‐and‐paper only or technology‐assisted examples. They then took a quiz on the material. The overall quiz results showed that the app group outperformed the control group. When learning through examples with the mobile app, students performed better on problems that required them to apply their knowledge, which corresponds to the third level of learning in Bloom's taxonomy. A postexperimental survey showed that students in the app group felt strongly that mobile apps helped them understand the new concepts more clearly and were more confident in their ability to learn the new material more quickly than the control group. Overall, this research demonstrates that incorporating mobile apps into lectures has the potential to positively affect student learning.
TRANSFORMING A FAMILY OF CURVES INTO A FAMILY OF CURVES WITH A SINGLE SHAPE
Authors: Levine Michael V. 
Published: August 2014

ABSTRACTThe relatively hard problem of transforming a given set of curves to curves with the same shape can sometimes be reduced to the easier problem of rendering curves parallel. In this paper a group is associated with the given curves, and it is shown that the reduction from the hard problem to the easy problem is valid whenever the group is nonabelian. A comprehensive review of earlier work is included so that this paper can be read alone. Applications to psychological measurement are cited briefly.
ESTIMATING PARAMETERS IN THE RASCH MODEL: REMOVING THE EFFECTS OF RANDOM GUESSING
Authors: Waller Michael I. 
Published: August 2014

ABSTRACTA method of estimating the parameters of the Rasch Model removing the effect of random guessing is presented. The procedure is an application of the ARRG model recently developed for two parameter latent trait models. Under the Rasch model ARRG provides for estimation of abilities, removing the effects of random guessing, without requiring the use of a computer. Monte Carlo simulations are employed to examine the accuracy of the resulting ability estimates.
FIELD DEPENDENCE AND INTERPERSONAL BEHAVIOR
Authors: Witkin Herman A. , Goodenough Donald R. 
Published: August 2014

ABSTRACTPeople with a field‐dependent or field‐independent cognitive style are different in their interpersonal behavior in ways predicted from the theory of psychological differentiation. Field‐dependent people make greater use of external social referents, but only when the situation is ambiguous and these referents provide information that helps remove the ambiguity; field‐independent people function with greater autonomy from others under such conditions. Field‐dependent people are more attentive to social cues than field‐independent people. Field‐dependent people have an interpersonal orientation: they show strong interest in others, prefer to be physically close to people, are emotionally open and gravitate toward social situations. Field‐independent people have an impersonal orientation: they are not very interested in others, show both physical and psychological distancing from people and prefer nonsocial situations. Finally, field‐dependent and field‐independent people are different in an array of characteristics which make it likely that field‐dependent people will get along better with others. Altogether, field‐dependent people have a set of social skills that are less evident in field‐independent people. On the other hand, field‐independent people have greater skill in cognitive analysis and structuring. This pattern suggests that, with regard to value judgments, the field‐dependence‐independence dimension is bipolar; each of the contrasting cognitive styles has components adaptive to particular situations.
VISUAL ASYMMETRY IN THE PERCEPTION OF FACES AND FIELD INDEPENDENCE
Authors: Oltman Philip K. , Ehrlichman Howard , Cox Patricia W. 
Published: August 2014

ABSTRACTIn a sample of 28 college males, it was found that the degree of lateral specialization of a right‐hemisphere function, the perception of faces, showed a correlation of .45 (p < .01) with extent of field‐independent performance, as assessed by a composite score based on the Embedded‐Figures Test, the Rod‐and‐Frame Test, and ratings on the Articulation‐of‐Body‐Concept Scale. In a second study with 16 female and 10 male college subjects using the Group Embedded‐Figures Test, field‐independent subjects again showed greater lateralization of face perception (r = .43, p < .05). Based on Witkin's view of field independence as a manifestation of psychological differentiation, possible links between extent of differentiation at the psychological and neurophysiological levels are suggested.
MOMENTARY FORGETTING: ENTERING AND LEAVING THE TOT STATE
Authors: Ryan Michael P. 
Published: August 2014

ABSTRACTThe frequent description of tip‐of‐the‐tongue CTOT) states as subthreshold memory traces is challenged by data showing that TOT genesis and TOT recovery are distinct processes. While encoding strategy is a strong predictor of TOT activity in paired‐associate forgetting as compared to several estimates of response strength, neither factor influences the order in which hints cue retrieval. It is concluded that TOTs represent a failure of decoding processes in mediated retrieval.
THE VALIDITY OF CLAUSAL PROCESSING STRATEGIES AT THE DISCOURSE LEVEL
Authors: Hurtig Richard 
Published: August 2014

ABSTRACTIn the last few years, considerable research in psycholinguistics has sought to test the hypothesis that the clause is a relevant segmentation unit in the processing of speech. The current interest in linguistic contexts and discourse analysis has raised the question of the validity of the clausal processing strategy suggested by Bever, Garrett, and Hurtig (1973). They demonstrated that the alternative readings of deep structure ambiguous sentences are available during the processing of a clause but that at the clause boundary only one reading remains available. They argued that such evidence supports a view of speech processing as operating clause by clause. It has, however, been suggested that the use of ambiguous sentences in linguistic argumentation or in the psycholinguistic investigation of speech processing is unjustified since phenomenally such sentences are never ambiguously perceived in context.Two sentence fragment completion experiments are presented to demonstrate that the clausal processing strategy is operative in the processing of an auditory speech signal and that the strategy is also operative in the larger discourse context. The analysis of the latency to completion data support the hypothesis that the clausal processing strategy demonstrated in research on sentences in isolation is also operative in connected discourse.This finding is consistent with the functional interactionist model of language proposed by Bever (1970) and Fodor, Bever, and Garrett (1974). Thus the notion of interactionism can be extended to account for discourse phenomena by characterizing the relationship of sentence grammar, discourse grammar, and the psychological processes operative in the encoding of sentences and discourses in the following way: The sentence (clause) is the on‐line perceptual unit while the discourse (proposition/idea set/logical event space) is the unit of cognitive (semantic) memory. That is, the discourse is the object of analysis at the cognitive organizational level while the sentence (syntactic structure) is the object of analysis at the production/comprehension level. Such an hypothesis thereby treats the research on sentences and discourse in linguistics as well as psychology as interactive models of the various subcomponents of a total linguistic‐cognitive system.