bluuebunny/crossref_metadata_2025_split huggingface dataset:
Withholding and canceling a response in ADHD adolescents
Authors: Bhaijiwala Mehereen , Chevrier Andre , Schachar Russell 
Published: June 2014

AbstractBackgroundDeficient response inhibition in situations involving a trade‐off between response execution and response stopping is a hallmark of attention deficit hyperactive disorder (ADHD). There are two key components of response inhibition; reactive inhibition where one attempts to cancel an ongoing response and prospective inhibition is when one withholds a response pending a signal to stop. Prospective inhibition comes into play prior to the presentation of the stop signal and reactive inhibition follows the presentation of a signal to stop a particular action. The aim of this study is to investigate the neural activity evoked by prospective and reactive inhibition in adolescents with and without ADHD.MethodsTwelve adolescents with ADHD and 12 age‐matched healthy controls (age range 9–18) were imaged while performing the stop signal task (SST).ResultsReactive inhibition activated right inferior frontal gyrus (IFG) in both groups. ADHD subjects activated IFG bilaterally. In controls, prospective inhibition invoked preactivation of the same part of right IFG that activated during reactive inhibition. In ADHD subjects, prospective inhibition was associated with deactivation in this region. Controls also deactivated the medial prefrontal cortex (MPFC) during prospective inhibition, whereas ADHD subjects activated the same area.DiscussionThis pattern of activity changes in the same structures, but in opposite directions, was also evident across all phases of the task in various task‐specific areas like the superior and middle temporal gyrus and other frontal areas.ConclusionDifferences between ADHD and control participants in task‐specific and default mode structures (IFG and MPFC) were evident during prospective, but not during reactive inhibition.
Iron(II)‐Derived Lewis Acid/Surfactant Combined Catalysis for the Enantioselective Mukaiyama Aldol Reaction in Pure Water
Authors: Lafantaisie Mathieu , Mirabaud Anaïs , Plancq Baptiste , Ollevier Thierry 
Published: June 2014

AbstractThe catalytic asymmetric Mukaiyama aldol reaction in pure water was performed by using a combination of iron(II) dodecyl sulfate, a chiral bipyridine ligand, and benzoic acid. By using the obtained iron(II)‐derived Lewis acid/surfactant combined catalyst, the desired products were afforded in good yields with high diastereo‐ and enantioselectivities.
Super‐Efficient Platinum Catalyst Derived from a Semiconducting, DMF Solvate: Structural, Spectroscopic, Electrochemical, and Catalytic Characterization
Authors: Lu Jinzhen , Abrahams Brendan F. , Winther‐Jensen Bjorn , Martin Lisandra L. , Bond Alan M. 
Published: June 2014

AbstractThe reaction of [(NH3)4Pt](NO3)2with LiTCNQF4(TCNQF4=2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane) in dimethylformamide gives the product [(NH3)4Pt](TCNQF4)2⋅(DMF)4(1). Subtle changes in the solvent conditions, however, result in a different product, [(NH3)4Pt](TCNQF4)2⋅Et2O⋅(CH3OH)4/3(2). Both1and2have been characterized by X‐ray crystallography, vibrational (FTIR, Raman) and UV/vis spectroscopy, thermogravimetric analysis and electrochemistry. Single crystals of1indicate the presence of 3 D networks supported by hydrogen bonding, whereas the structural analysis of2indicates a 2 D layered network, which consists of alternating TCNQF4−and [(NH3)4Pt]2+layers. The conductivity of a single crystal of1at room temperature lies in the semiconducting range (≈2.5×10−6 S cm−1). Unexpectedly,1was found to exhibit an exceptionally high catalytic activity for the electron transfer reaction between ferricyanide and thiosulfate ions in aqueous media. Our analysis indicates that the DMF solvates were removed prior to the catalytic reaction, but no other changes that occur in the chemical composition were found. Thus, the active catalyst is [(NH3)4Pt](TCNQF4)2(3) rather than the starting material1.
Mechanistic Study of CO Titration on CuxO/Cu(1 1 1) (x≤2) Surfaces
Authors: An Wei , Baber Ashleigh E. , Xu Fang , Soldemo Markus , Weissenrieder Jonas , Stacchiola Dario , Liu Ping 
Published: June 2014

AbstractThe reducibility of metal oxides is of great importance to their catalytic behavior. Herein, we combined ambient‐pressure scanning tunneling microscopy (AP–STM), X‐ray photoemission spectroscopy (AP–XPS), and DFT calculations to study the CO titration of CuxO thin films supported on Cu(1 1 1) (CuxO/Cu(1 1 1)) aiming to gain a better understanding of the roles that the Cu(1 1 1) support and surface defects play in tuning catalytic performances. Different conformations have been observed during the reduction, namely, the 44 structure and a recently identified (5–7–7–5) Stone–Wales defects (5–7 structure). The DFT calculations revealed that the Cu(1 1 1) support is important to the reducibility of supported CuxO thin films. Compared with the case for the Cu2O(1 1 1) bulk surface, at the initial stage CO titration is less favorable on both the 44 and 5–7 structures. The strong CuxO↔Cu interaction accompanied with the charge transfer from Cu to CuxO is able to stabilize the oxide film and hinder the removal of O. However, with the formation of more oxygen vacancies, the binding between CuxO and Cu(1 1 1) is weakened and the oxide film is destabilized, and Cu2O(1 1 1) is likely to become the most stable system under the reaction conditions. In addition, the surface defects also play an essential role. With the proceeding of the CO titration reaction, the 5–7 structure displays the highest activity among all three systems. Stone–Wales defects on the surface of the 5–7 structure exhibit a large difference from the 44 structure and Cu2O(1 1 1) in CO binding energy, stability of lattice oxygen, and, therefore, the reduction activity. The DFT results agree well with the experimental measurements, demonstrating that by adopting the unique conformation, the 5–7 structure is the active phase of CuxO, which is able to facilitate the redox reaction and the Cu2O/Cu(1 1 1)↔Cu transition.
Direct Reductive Amination of Ketones: Structure and Activity of S‐Selective Imine Reductases from Streptomyces
Authors: Huber Tobias , Schneider Lisa , Präg Andreas , Gerhardt Stefan , Einsle Oliver , Müller Michael 
Published: June 2014

AbstractThe importance and structural diversity of chiral amines is well‐demonstrated by the myriad nonenzymatic methods for their chemical production. In nature, the production of amines is performed by transamination rather than by reduction of an imine precursor derived from the corresponding ketone. Imine reductases, however, show great potential in the reduction of cyclic imines that are stable towards hydrolysis in aqueous reaction media. Here, we report the catalytic activity of two S‐selective imine reductases towards 3,4‐dihydroisoquinolines and 3,4‐dihydro‐β‐carbolines and their activity in the direct reductive amination of ketone substrates. The crystal structures of the enzyme from Streptomyces sp. GF3546 in complex with the cofactor NADPH and from Streptomyces aurantiacus in native form have been solved and refined to a resolution of 1.9 Å.
A Soluble Ladder‐Conjugated Star‐Shaped Oligomer Composed of Four Perylene Diimide Branches and a Fluorene Core: Synthesis and Properties
Authors: Zhang Youdi , Chen Lingcheng , Zhang Kaichen , Wang Helin , Xiao Yi 
Published: June 2014

AbstractA new ladder‐conjugated star‐shaped oligomer electron‐transporting material TetraPDI‐PF, with four perylene diimide (PDI) branches and a fluorene core, was efficiently synthesized. The oligomer is highly soluble in dichlorobenzene with a solubility of 155 mg mL−1, which is higher than those of PDI (35 mg mL−1) and PDI‐Phen (70 mg mL−1). Demonstrated by thermogravimetric analysis (TGA), the oligomer exhibits excellent thermal stability with the decomposition temperature (Td) of 291.2 °C, which is 65 °C higher than that of PDI. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were employed to investigate the electrochemical properties. Although the CV curves of TetraPDI‐PF are successively scanned for 15 cycles, they still remain invariable reduction potentials. The oligomer also shows outstanding photostability, even better than PDI, which maintains 99 % fluorescence intensity after irradiation for 10 min using maximum laser intensity. In the steady‐state space‐charge‐limited current (SCLC) devices, TetraPDI‐PF exhibits higher intrinsic electron mobility of 2.22×10−5 cm2 V−1 s−1, three orders of magnitude over that of PDI (3.52×10−8 cm2 V−1 s−1). The bulk heterojunction (BHJ) organic solar cells (OSCs) using TetraPDI‐PF as non‐fullerene acceptors and P3HT as donors give optimum power conversion efficiency (PCE) of 0.64 %, which is 64 times that of the PDI:P3HT BHJ cells.
A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SFn (n=1, 2, 4), PF5, and ClF3
Authors: Braida Benoit , Ribeyre Tristan , Hiberty Philippe C. 
Published: June 2014

AbstractSome typical hypervalent molecules, SF4, PF5, and ClF3, as well as precursors SF (4Σ− state) and SF2 (3B1 state), are studied by means of the breathing‐orbital valence bond (BOVB) method, chosen for its capability of combining compactness with accuracy of energetics. A unique feature of this study is that for the first time, the method used to gain insight into the bonding modes is the same as that used to calculate the bonding energies, so as to guarantee that the qualitative picture obtained captures the essential physics of the bonding system. The 4Σ− state of SF is shown to be bonded by a three‐electron σ bond assisted by strong π back‐donation of dynamic nature. The linear 3B1 state of SF2, as well as the ground states of SF4, PF5 and ClF3, are described in terms of four VB structures that all have significant weights in the range 0.17–0.31, with exceptionally large resonance energies arising from their mixing. It is concluded that the bonding mode of these hypervalent species and isoelectronic ones complies with Coulson’s version of the Rundle–Pimentel model, but assisted by charge‐shift bonding. The conditions for hypervalence to occur are stated.
Probing the Rotational Dynamics of meso‐(2‐Substituted)aryl Substituents in A2B‐Type Subporphyrins
Authors: Yoshida Kota , Copley Graeme , Mori Hirotaka , Osuka Atsuhiro 
Published: June 2014

AbstractA2B‐type B‐methoxy subporphyrins 3 a–g and B‐phenyl subporphyrins 7 a–c,e,g bearing meso‐(2‐substituted)aryl substituents are synthesized, and their rotational dynamics are examined through variable‐temperature (VT) 1H NMR spectroscopy. In these subporphyrins, the rotation of meso‐aryl substituents is hindered by a rationally installed 2‐substituent. The rotational barriers determined are considerably smaller than those reported previously for porphyrins. Comparison of the rotation activation parameters reveals a variable contribution of ΔH≠ and ΔS≠ in ΔG≠. 2‐Methyl and 2‐ethyl groups of the meso‐aryl substituents in subporphyrins 3 e, 3 f, and 7 e induce larger rotational barriers than 2‐alkoxyl substituents. The rotational barriers of 3 g and 7 g are reduced by the presence of the 4‐dibenzylamino group owing to its ability to stabilize the coplanar rotation transition state electronically. The smaller rotational barriers found for B‐phenyl subporphyrins than for B‐methoxy subporphyrins indicate a negligible contribution of SN1‐type heterolysis in the rotation of meso‐aryl substituents.
2‐Chloro‐Azaborolyl Anion: A Source of 1,2‐Azaborole Isosteric to Cyclopentadienylidene
Authors: Xie Liang , Zhang Jianying , Cui Chunming 
Published: June 2014

AbstractAzaborolyl anions, the five‐membered BN heterocycles, have attracted a considerable attention due to their aromaticity and isoelectronic relationship with ubiquitous cyclopentadienyl ligands. Besides their syntheses and applications in the preparation of metal complexes, the other aspects of their chemistry have been virtually unexplored. Reduction of the azabutadienyl chelate boron dichloride [ArNC(R)CHC(R)]BCl2 (2, Ar=2,6‐Me2C6H3, R=tBu) with two equivalents of potassium yielded the novel 2‐chloro‐azaborolyl anion [ArNC(R)CHC(R)BCl]K(thf) (3) as a stable product in good yield. Reaction of 3 with 1,3,4,5‐tetramethylimidazol‐2‐ylidene (NHC) yielded the first NHC–azaborole adduct with the elimination of KCl. The salt elimination reaction was also observed in the reactions with H2O and the organic azide ArN3, leading to the formation of an oxo‐bridged 3H‐1,2‐diazaborole and an intramolecular donor‐stabilized iminoborane, demonstrating that 3 is a source of the unexplored 1,2‐azaborole isosteric to cyclopentadienylidene.
Large Spin‐Relaxation Barriers for the Low‐Symmetry Organolanthanide Complexes [Cp*2Ln(BPh4)] (Cp*=pentamethylcyclopentadienyl; Ln=Tb, Dy)
Authors: Demir Selvan , Zadrozny Joseph M. , Long Jeffrey R. 
Published: June 2014

AbstractSingle‐molecule magnets comprising one spin center represent a fundamental size limit for spin‐based information storage. Such an application hinges upon the realization of molecules possessing substantial barriers to spin inversion. Axially symmetric complexes of lanthanides hold the most promise for this due to their inherently high magnetic anisotropies and low tunneling probabilities. Herein, we demonstrate that strikingly large spin reversal barriers of 216 and 331 cm−1 can also be realized in low‐symmetry lanthanide tetraphenylborate complexes of the type [Cp*2Ln(BPh4)] (Cp*=pentamethylcyclopentadienyl; Ln=Tb (1) and Dy (2)). The dysprosium congener showed hysteretic magnetization data up to 5.3 K. Further studies of the magnetic relaxation processes of 1 and 2 under applied dc fields and upon dilution within a matrix of [Cp*2Y(BPh4)] revealed considerable suppression of the tunneling pathway, emphasizing the strong influence of dipolar interactions on the low‐temperature magnetization dynamics in these systems.
A chaotic map‐based anonymous multi‐server authenticated key agreement protocol using smart card
Authors: Tsai Jia‐Lun , Lo Nai‐Wei 
Published: June 2014

SummaryAuthenticated key agreement protocols play an important role for network‐connected servers to authenticate remote users in Internet environment. In recent years, several authenticated key agreement protocols for single‐server environment have been developed based on chaotic maps. In modern societies, people usually have to access multiple websites or enterprise servers to accomplish their daily personal matters or duties on work; therefore, how to increase user's convenience by offering multi‐server authentication protocol becomes a practical research topic. In this study, a novel chaotic map‐based anonymous multi‐server authenticated key agreement protocol using smart card is proposed. In this protocol, a legal user can access multiple servers using only a single secret key obtained from a trusted third party, known as the registration center. Security analysis shows this protocol is secure against well‐known attacks. In addition, protocol efficiency analysis is conducted by comparing the proposed protocol with two recently proposed schemes in terms of computational cost during one authentication session. We have shown that the proposed protocol is twice faster than the one proposed by Khan and He while preserving the same security properties as their protocol has. Copyright © 2014 John Wiley & Sons, Ltd.
Does imprint cytology improve the accuracy of transrectal prostate needle biopsy?
Authors: Sayar Hamide , Bulut Burak Besir , Bahar Abdulkadir Yasir , Bahar Mustafa Remzi , Seringec Nurten , Resim Sefa , Çıralık Harun 
Published: June 2014

ObjectiveTo evaluate the accuracy of imprint cytology of core needle biopsy specimens in the diagnosis of prostate cancer.MethodsBetween December 24, 2011 and May 9, 2013, patients with an abnormal DRE and/or serum PSA level of >2.5 ng/mL underwent transrectal prostate needle biopsy. Samples with positive imprint cytology but negative initial histologic exam underwent repeat sectioning and histological examination.Results1,262 transrectal prostate needle biopsy specimens were evaluated from 100 patients. Malignant imprint cytology was found in 236 specimens (18.7%), 197 (15.6%) of which were confirmed by histologic examination, giving an initial 3.1% (n = 39) rate of discrepant results by imprint cytology. Upon repeat sectioning and histologic examination of these 39 biopsy samples, 14 (1.1% of the original specimens) were then diagnosed as malignant, 3 (0.2%) as atypical small acinar proliferation (ASAP), and 5 (0.4%) as high‐grade prostatic intraepithelial neoplasia (HGPIN). Overall, 964 (76.4%) specimens were negative for malignancy by imprint cytology. Seven (0.6%) specimens were benign by cytology but malignant cells were found on histological evaluation. On imprint cytology examination, nonmalignant but abnormal findings were seen in 62 specimens (4.9%). These were all due to benign processes. After reexamination, the accuracy, sensitivity, specificity, positive predictive value, negative predictive value, false‐positive rate, false‐negative rate of imprint preparations were 98.1, 96.9, 98.4, 92.8, 99.3, 1.6, 3.1%, respectively.ConclusionImprint cytology is valuable tool for evaluating TRUS‐guided core needle biopsy specimens from the prostate. Use of imprint cytology in combination with histopathology increases diagnostic accuracy when compared with histopathologic assessment alone. Diagn. Cytopathol. 2015;43:91–97. © 2014 Wiley Periodicals, Inc.
Origins of the Ideas in Evaluating with Validity
Authors: House Ernest R. 
Published: June 2014

AbstractThe book Evaluating with Validity (House, ) broadened the evaluation field's conception of validity by contending that evaluations should be true, coherent, and just. Untrue, incoherent, and unjust evaluations are invalid. The working ideas were argument, coherence, and politics. Truth is the attainment of arguments soundly made, beauty is the attainment of coherence well wrought, and justice is the attainment of politics fairly done. For the truth criterion, it wasn't designs or correlations that determined validity, but rather the validity of the arguments that supported the use of the designs and correlations. The broader conception of validity grew from addressing problems encountered in conducting evaluations. This chapter traces the origins of the ideas and the social context from which they emerged. It contends that these criteria still apply, though the contents of the criteria have changed somewhat and the context has changed substantially.
Credible Judgment: Combining Truth, Beauty, and Justice
Authors: Hurteau Marthe , Williams David D. 
Published: June 2014

AbstractThe research summarized in this chapter provides descriptive evidence to support House's vision of validity by expanding connections with his theory to a wide variety of professions, in addition to professional evaluators. Perhaps these results and discussion of them and the emerging model will invite professionals to reflect upon ways to improve their own evaluative judgments. Case study interviews were conducted in Canada and the United States with 27 professionals from many helping professions, including law and law enforcement, social work, medicine, education, business, sports, and chaplaincy. Participants were asked to discuss examples of successful and less successful evaluative judgments they had made in their professional work. Citing patterns discovered through analysis of these contrasting examples, we linked their experiences to House's framework regarding truth, beauty, and justice as foundations for validity. This research thus generated a descriptive model of a process to produce credible evaluation judgments with six interacting elements: (1) credible judgments evolve through an iterative process; (2) frameworks, protocols, and methods may help professionals generate valid evidence, but they are often not sufficient; (3) stakeholders’ involvement is essential, and how they participate varies depending on the circumstances; (4) the path required to generate a credible judgment is rarely linear; (5) credible judgment is based on strong argumentation that is properly developed and aesthetically presented; (6) the production of credible judgments depends on special dispositions, orientations, or qualities of the professionals.
Negotiating Truth, Beauty, and Justice: A Politically Responsive Approach
Authors: Azzam Tarek , Levine Bret 
Published: June 2014

AbstractEvaluation design and implementation are not technocratic exercises, but are processes that require negotiations with stakeholders and careful design. This chapter focuses on the nontechnical factors that affect these processes and discusses cases and studies to illustrate their influence. The chapter concludes by introducing the concept of politically responsive evaluation as an organizing frame to help evaluators consider some of the nontechnical issues that influence evaluations.
Justice Signposts in Evaluation Theory, Practice, and Policy
Authors: Hopson Rodney K. 
Published: June 2014

AbstractThis chapter, influenced by Ernest House's conceptions of justice from his Evaluating with Validity seminal book, offers two justice signposts in contemporary evaluation theory, practice, and policy. The justice turn in evaluation privileges issues of power, fairness, justice, and rights beyond practical and technical considerations. Cases and examples draw upon Housian notions of justice in advancing and making obvious how evaluation may contribute to more just practices, systems, and structures in our larger society.
Selective Synthesis of Quinolines and Indoles: Sulfur‐Assisted or Selenium‐Catalyzed Reaction of β‐(2‐Nitrophenyl)‐α,β‐unsaturated Ketones with Carbon Monoxide
Authors: Umeda Rui , Kouno Hiroshi , Kitagawa Takayuki , Okamoto Tomohiro , Kawashima Keisuke , Mashino Tsukasa , Nishiyama Yutaka 
Published: June 2014

ABSTRACTA simple and selective synthetic method of quinolines and indoles by the reaction of β‐(2‐nitrophenyl)‐α,β‐unsaturated ketones with carbon monoxide was developed. When β‐(2‐nitrophenyl)‐α,β‐unsaturated ketones were allowed to react with carbon monoxide and water in the presence of a stoichiometric amount of sulfur or a catalytic amount of selenium, the corresponding quinolines were produced in moderate‐to‐good yields. On the other hand, in the absence of water, the indoles were produced by the selenium‐catalyzed reaction of the β‐(2‐nitrophenyl)‐α,β‐unsaturated ketones with carbon monoxide.
Synthesis of the Mixed Alkyl Esters of Phenylphosphonic Acid by Two Variations of the Atherton–Todd Protocol
Authors: Ilia Gheorghe , Petric Mihaela , Bálint Erika , Keglevich György 
Published: June 2014

ABSTRACTPhenylphosphonates with mixed alkyl groups were synthesized from ethyl phenyl‐H‐phosphinate by two modified Atherton–Todd methods. Using aqueous sodium hydroxide under phase transfer catalytic conditions, the alkyl ethyl phosphonates were obtained in only moderate yields. However, applying 1‐methylimidazole as the base, the diesters could be prepared in yields of 76–85%. The imidazole hydrochloride formed as a by‐product acts as an ionic liquid phase in the reaction, from which the base can be regenerated.