bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Aggregation‐Induced‐Emission Platform for Direct Visualization of Interfacial Dynamic Self‐Assembly
Authors: Li Junwei , Li Yuan , Chan Carrie Y. K. , Kwok Ryan T. K. , Li Hongkun , Zrazhevskiy Pavel , Gao Xiaohu , Sun Jing Zhi , Qin Anjun , Tang Ben Zhong 
Published: October 2014

AbstractAn in‐depth understanding of dynamic interfacial self‐assembly processes is essential for a wide range of topics in theoretical physics, materials design, and biomedical research. However, direct monitoring of such processes is hampered by the poor imaging contrast of a thin interfacial layer. We report in situ imaging technology capable of selectively highlighting self‐assembly at the phase boundary in real time by employing the unique photophysical properties of aggregation‐induced emission. Its application to the study of breath‐figure formation, an immensely useful yet poorly understood phenomenon, provided a mechanistic model supported by direct visualization of all main steps and fully corroborated by simulation and theoretical analysis. This platform is expected to advance the understanding of the dynamic phase‐transition phenomena, offer insights into interfacial biological processes, and guide development of novel self‐assembly technologies.
Asymmetric Synthesis of 2,3‐Dihydropyrroles by Ring‐Opening/Cyclization of Cyclopropyl Ketones Using Primary Amines
Authors: Xia Yong , Liu Xiaohua , Zheng Haifeng , Lin Lili , Feng Xiaoming 
Published: October 2014

AbstractThe asymmetric ring‐opening/cyclization of cyclopropyl ketones with primary amine nucleophiles was catalyzed by a chiral N,N′‐dioxide/scandium(III) complex through a kinetic resolution process. A broad range of cyclopropyl ketones and primary amines are suitable substrates of this reaction. The corresponding products were afforded in excellent enantioselectivities and yields (up to 97 % ee and 98 % yield) under mild reaction conditions. This method provides a promising access to chiral 2,3‐dihydropyrroles as well as an effective procedure for the kinetic resolution of 2‐substituted cyclopropyl ketones.
Long‐Distance Electronic Energy Transfer in Light‐Harvesting Supramolecular Polymers
Authors: Winiger Christian B. , Li Shaoguang , Kumar Ganesh R. , Langenegger Simon M. , Häner Robert 
Published: October 2014

AbstractThe efficient collection of solar energy relies on the design and construction of well‐organized light‐harvesting systems. Herein we report that supramolecular phenanthrene polymers doped with pyrene are effective collectors of light energy. The linear polymers are formed through the assembly of short amphiphilic oligomers in water. Absorption of light by phenanthrene residues is followed by electronic energy transfer along the polymer over long distances (>100 nm) to the accepting pyrene molecules. The high efficiency of the energy transfer, which is documented by large fluorescence quantum yields, suggests a quantum coherent process.
A Noncanonical Function of Sortase Enables Site‐Specific Conjugation of Small Molecules to Lysine Residues in Proteins
Authors: Bellucci Joseph J. , Bhattacharyya Jayanta , Chilkoti Ashutosh 
Published: October 2014

AbstractWe provide the first demonstration that isopeptide ligation, a noncanonical activity of the enzyme sortase A, can be used to modify recombinant proteins. This reaction was used in vitro to conjugate small molecules to a peptide, an engineered targeting protein, and a full‐length monoclonal antibody with an exquisite level of control over the site of conjugation. Attachment to the protein substrate occurred exclusively through isopeptide bonds at a lysine ε‐amino group within a specific amino acid sequence. This reaction allows more than one molecule to be site‐specifically conjugated to a protein at internal sites, thereby overcoming significant limitations of the canonical native peptide ligation reaction catalyzed by sortase A. Our method provides a unique chemical ligation procedure that is orthogonal to existing methods, supplying a new method to site‐specifically modify lysine residues that will be a valuable addition to the protein conjugation toolbox.
Effects of processing conditions on foaming behaviors of polyetherimide (PEI) and PEI/polypropylene blends in microcellular injection molding process
Authors: Liu Tao , Lei Yajie , Chen Zhenglun , Wang Xianzhong , Luo Shikai 
Published: October 2014

ABSTRACTFoaming behaviors of both neat polyetherimide (PEI) and PEI/polypropylene (PP) blends were studied in this article in microcellular injection molding (Mucell) process. The study mainly focused on the comparison of two materials' foaming behaviors under different processing conditions which took a critical effect on the morphologies of foams. The results indicated that the different characteristics of PEI and PEI/PP blends, such as melt strength, gas dissolvability, and solubility, induced different nucleation ability of PEI and PEI/PP blends. The addition of PP could obviously improve the cell density and reduce the cell size. With the processing conditions changing, the morphologies of PEI/PP altered more variously, and their distribution of cell density was wider. This suggested that foaming behaviors of PEI/PP blends was more flexible to be controlled by the processing conditions than neat PEI. The effects of shot size, gas injection, and injection rate on foam morphologies were studied in detail. Shot size determined the weight reduction of samples and affected the cell density and size significantly. Gas dosing time and dosing rate determined the gas ratio which effected on foam morphologies of the PEI and PEI/PP foams. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41443.
An Iminocoumarin Sulfonamide Based Turn‐On Fluorescent Probe for the Detection of Biothiols in Aqueous Solution
Authors: Yang Yan‐Ling , Zhang Fu‐Ming , Wang Ya‐Wen , Zhang Bao‐Xin , Fang Ran , Fang Jian‐Guo , Peng Yu 
Published: October 2014

AbstractA new chemodosimeter for the highly selective sensing and imaging of biothiols was designed and realized in phosphate‐buffered saline solution at pH 7.4 through a fluorescence “off–on” response. A unique mechanism featuring a two‐step cascade (biothiols→H2O) sequence for this remarkable recognition is disclosed for the first time.
Oropharyngeal teratoma, oral duplication, cervical diplomyelia and anencephaly in a 22‐week fetus: A review of the craniofacial teratoma syndrome
Authors: Morlino Silvia , Castori Marco , Servadei Francesca , Laino Luigi , Silvestri Evelina ,   Pediatric Craniofacial Malformation (PECRAM) Study Group, Grammatico Paola 
Published: October 2014

BackgroundOropharyngeal teratoma may occur by itself or together with other craniofacial malformations, most commonly cleft palate. Oropharyngeal teratoma may be also seen in association with frontonasal dysplasia and/or various degrees of craniofacial duplication. The nosology of these sporadic disorders is poorly defined.Case and ReviewWe report on a 22‐week fetus with a protruding nasopharyngeal teratoma, partial oral duplication, anencephaly, multiple costo‐vertebral segmentation defects, and cervical diplomyelia. A review of the literature identified 48 patients published from 1931 to 2013 with co‐existing clefting and duplication anomalies of the cephalic pole. Thoracic and abdominal midline anomalies were reported 13 times.ConclusionThe term “craniofacial teratoma syndrome” is introduced to define this phenotype as a recognizable developmental field defect of the cephalic pole. Developmental pathogenesis is discussed with a focus on pleiotropy and stereotaxis. The observation of midline findings suggestive of holoprosencephaly in a few previously reported cases suggests a role for the sonic hedgehog signaling pathway in this malformation pattern. Birth Defects Research (Part A) 103:554–566, 2015. © 2014 Wiley Periodicals, Inc.
Synthetic secondary chromosomes in Escherichia coli based on the replication origin of chromosome II in Vibrio cholerae
Authors: Messerschmidt Sonja J. , Kemter Franziska S. , Schindler Daniel , Waldminghaus Torsten 
Published: October 2014

AbstractRecent developments in DNA‐assembly methods make the synthesis of synthetic chromosomes a reachable goal. However, the redesign of primary chromosomes bears high risks and still requires enormous resources. An alternative approach is the addition of synthetic chromosomes to the cell. The natural secondary chromosome of Vibrio cholerae could potentially serve as template for a synthetic secondary chromosome in Escherichia coli. To test this assumption we constructed a replicon named synVicII based on the replication module of V. cholerae chromosome II (oriII). A new assay for the assessment of replicon stability was developed based on flow‐cytometric analysis of unstable GFP variants. Application of this assay to cells carrying synVicII revealed an improved stability compared to a secondary replicon based on E. coli oriC. Cell cycle analysis and determination of cellular copy numbers of synVicII indicate that replication timing of the synthetic replicon in E. coli is comparable to the natural chromosome II (ChrII) in V. cholerae. The presented synthetic biology work provides the basis to use secondary chromosomes in E. coli to answer basic research questions as well as for several biotechnological applications.
Implementation of responsible Procurement Management: An Institutional Perspective
Authors: Ferri Laura Maria , Oelze Nelly , Habisch André , Molteni Mario 
Published: October 2014

AbstractThe role of the institutional context in the pattern of the implementation of responsible procurement management (RPM) has been object of very limited previous research, although it has been found that it affects the approach to both CSR and supply chain management. The article presents the results of an in‐depth comparative study drawing on 47 interviews with managers of 13 companies in Italy and Germany, which have been previously related to different national institutional settings. The analysis demonstrates that the perception of factors influencing RPM implementation differs between Italian and German companies, and suggests that the institutional context affects not only the overall CSR behavior of the company, but also its institutionalization into a specific function. Results show that the institutional context mainly determines the boundaries within which practitioners are able to operate, whereas the ability to effectively bring about changes in their activity mainly depends upon organizational environment. Copyright © 2014 John Wiley & Sons, Ltd and ERP Environment
Corporate Ownership and Environmental Proactivity
Authors: Calza Francesco , Profumo Giorgia , Tutore Ilaria 
Published: October 2014

AbstractThe present paper advances knowledge of the drivers of firms' proactive environmental strategies. In particular, it explores the relationship between different corporate ownership structures and firms' green proactivity, in order to see whether some types of shareholder act as a stimulating driver for firms' proactive environmental behaviors. The study examines the explanatory power of corporate governance issues, such as a firm's ownership structure, as potential determinants of companies' environmental proactivity. Attention is focused on the European firms included into the Carbon Disclosure Project questionnaire 2012.The results show that ownership structure matters in firms' environmental proactivity. In particular, firms with a higher percentage of state ownership present superior green proactivity, while ownership concentration appears negatively related to proactive environmental strategy.The paper offers theoretical and practical implications. It focuses attention on a still underdeveloped research area, namely organizations and their relationship with the natural environment, including corporate ownership as a driver of a company's proactive environmental strategy. Copyright © 2014 John Wiley & Sons, Ltd and ERP Environment
How Do Strengths and Weaknesses in Corporate Social Performance Across Different Stakeholder Domains Affect Company Performance?
Authors: Kumar Kamalesh , Boesso Giacomo , Michelon Giovanna 
Published: October 2014

AbstractThe existing research on corporate social responsibility (CSR) has largely focused on the positive aspect of corporate social performance (CSP) and company performance (CP) and ignored the relationship between actions that would qualify as negative CSP (or weakness in CSP) towards a stakeholder group and company performance. Using data from the KLD collected over a three‐year period, this study examines the relationship between both CSP weaknesses and strengths and CP across individual stakeholder domains. Results of the study suggest that strengths in CSP related to primary stakeholder domains are associated with superior company performance. However, this relationship is tenuous, at best, in the case of the secondary stakeholder domain. As for weaknesses in CSP, the results suggest that if a firm performs poorly in meeting the expectations of one or more stakeholders it is penalized in the form of poor performance. This finding generally holds true for both primary and secondary stakeholders. Implications of these findings for public policy and businesses planning to address social issues are discussed. Copyright © 2014 John Wiley & Sons, Ltd and ERP Environment
Catalytic Hydrotreatment of Fatty Acid Methyl Esters to Diesel‐like Alkanes Over Hβ Zeolite‐supported Nickel Catalysts
Authors: Chen Liangguang , Fu Junying , Yang Lingmei , Chen Zibo , Yuan Zhenhong , Lv Pengmei 
Published: October 2014

AbstractA Ni/Hβ zeolite catalyst was prepared for the selective transformation of fatty acid methyl esters (FAMEs) into diesel‐like alkanes through hydrotreatment. Characterization of the physicochemical properties of a 10 wt % nickel‐loaded, Hβ zeolite support indicated that nickel(II) oxide aggregated into large particles approximately 23.9 nm in size, whereas nickel aggregated into particles 18.3 nm in size, significantly increasing the total acid sites of Hβ zeolite after hydrogen reduction. The reaction scheme of the whole FAME transformation was investigated by using a batch reactor. It was found that FAMEs were first hydrogenated mainly to saturated fatty acids, followed by hydrodeoxygenation without carbon loss, the main route toward alkanes. The hydrotreatment of FAMEs by decarboxylation or decarbonylation was favored at high temperatures and low hydrogen pressures on Hβ zeolite with higher nickel loadings. The metallic and acidic functionalities of nickel/Hβ zeolite catalysts exhibited a synergistic effect in hydrodeoxygenation without carbon loss, achieving high FAME conversion and yields of liquid C16 and C18 alkanes. Optimal catalytic performances were obtained with 10 wt % nickel loading over Hβ zeolite (Si/Al=25) at 270 °C with a pressure of 1.0 MPa H2 over 8 h. A maximum alkane product yield of 93.2 % was achieved for C15–C18 alkanes with complete FAME conversion. 80.3 % FAME conversion could was achieved after eight reaction cycles by using the nickel/Hβ zeolite catalyst with calcination after every use.
Multistereogenic Phosphine Ligand‐promoted Palladium‐Catalyzed Allylic Alkylation of Cyanoesters
Authors: Deng Wen‐Hui , Ye Fei , Bai Xing‐Feng , Zheng Zhan‐Jiang , Cui Yu‐Ming , Xu Li‐Wen 
Published: October 2014

AbstractA palladium‐catalyzed allylic alkylation of unsubstituted 2‐cyanoacetates using a 1,1′‐bi‐2‐naphthol‐derived multifunctional N,O,P ligand is reported. A number of chiral monosubstituted 2‐cyanoacetates with two adjacent stereogenic carbon centers are obtained in this Pd‐catalyzed asymmetric allylic alkylation reaction, in which the multistereogenic and multifunctional 1,1′‐bi‐2‐naphthol‐derived N,O,P ligand‐promoted Pd‐catalyzed asymmetric allylic alkylation reaction proceeds smoothly in high diastereo‐ and enantioselectivity (up to >99:1 dr and up to 96 % ee).
An Improved Correlation of the Mean Drop Size in a Modified Scheibel Extraction Column
Authors: Yuan Shenfeng , Jin Shuangfeng , Chen Zhirong , Yuan Yanna , Yin Hong 
Published: October 2014

AbstractThe drop size is of fundamental importance in the design of liquid‐liquid extraction columns, the drop size was measured as a function of the geometry, operating conditions, and physical properties of a liquid‐liquid system with no mass transfer in a five‐stage modified Scheibel extraction column. An improved correlation of the mean drop size in the Scheibel extraction column is presented. The correlation was divided into three sections in terms of the Reynolds number. It could be applied in a wide range and could be further used for the study of mass transfer performance of the modified Scheibel extraction column.
Chloride‐Selective Electrodes Based on “Two‐Wall” Aryl‐Extended Calix[4]Pyrroles: Combining Hydrogen Bonds and Anion–π Interactions to Achieve Optimum Performance
Authors: Sabek Jad , Adriaenssens Louis , Guinovart Tomàs , Parra Enrique J. , Rius F. Xavier , Ballester Pablo , Blondeau Pascal 
Published: October 2014

AbstractThe performance of chloride‐selective electrodes based on “two‐wall” aryl‐extended calix[4]pyrroles and multiwall carbon nanotubes is presented. The calix[4]pyrrole receptors bear two phenyl groups at opposite meso‐positions. When the meso‐phenyl groups are decorated with strong electron‐withdrawing substituents, attractive anion–π interactions may exist between the receptor’s aromatic walls and the sandwiched anion. These anion–π interactions are shown to significantly affect the selectivity of the electrodes. Calix[4]pyrrole, bearing a p‐nitro withdrawing group on each of the meso‐phenyl rings, afforded sensors that display anti‐Hofmeister behavior against the lipophilic salicylate and nitrate anions. Based on the experimental data, a series of principles that help in predicting the suitability of synthetic receptors for use as anion‐specific ionophores is discussed. Finally, the sensors deliver excellent results in the direct detection of chloride in bodily fluids.
Kekulé versus Lewis: When Aromaticity Prevents Electron Pairing and Imposes Polyradical Character
Authors: Trinquier Georges , Malrieu Jean‐Paul 
Published: October 2014

AbstractSome conjugated alternant hydrocarbons, of singlet ground state according to Ovchinnikov’s rule, may exhibit strong polyradical character, despite admitting complete pairing of electrons in bond orbitals between adjacent atoms. Typical organizations of this kind are encountered in polycyclic frames supporting two or more extracyclic methylene groups. Lewis bond pairing would require quinonization of six‐membered rings, whereas safeguarding aromaticity proves sufficient to impose ground‐state open‐shell character, that is, the existence of unpaired electrons, providing the number of benzene rings to be quinonized is larger than two. Several examples built as variations around para‐polyphenylene frames are examined through unrestricted DFT (UDFT) calculations, using various methods for spin decontamination of wavefunctions, geometries, and singlet–triplet energy gaps. They all illustrate how it is possible to conceive architectures that can be written with a closed‐shell bond pairing, although they exhibit a large number of unpaired electrons. The same analyses also apply to systems in which quinonization would not kill but only reduce the number of unpaired electrons.
Rhodium(III)‐Catalyzed Three‐Component Reaction of Imines, Alkynes, and Aldehydes through CH Activation
Authors: Huang Ji‐Rong , Song Qiang , Zhu Yu‐Qin , Qin Liu , Qian Zhi‐Yong , Dong Lin 
Published: October 2014

AbstractAn efficient rhodium(III)‐catalyzed tandem three‐component reaction of imines, alkynes and aldehydes through CH activation has been developed. High stereo‐ and regioselectivity, as well as good yields were obtained in most cases. The simple and atom‐economical approach offers a broad scope of substrates, providing polycyclic skeletons with potential biological properties.
NHC→SiCl4: An Ambivalent Carbene‐Transfer Reagent
Authors: Böttcher Tobias , Steinhauer Simon , Lewis‐Alleyne Lesley C. , Neumann Beate , Stammler Hans‐Georg , Bassil Bassem S. , Röschenthaler Gerd‐Volker , Hoge Berthold 
Published: October 2014

AbstractThe addition of BCl3 to the carbene‐transfer reagent NHC→SiCl4 (NHC=1,3‐dimethylimidazolidin‐2‐ylidene) gave the tetra‐ and pentacoordinate trichlorosilicon(IV) cations [(NHC)SiCl3]+ and [(NHC)2SiCl3]+ with tetrachloroborate as counterion. This is in contrast to previous reactions, in which NHC→SiCl4 served as a transfer reagent for the NHC ligand. The addition of BF3⋅OEt2, on the other hand, gave NHC→BF3 as the product of NHC transfer. In addition, the highly Lewis acidic bis(pentafluoroethyl)silane (C2F5)2SiCl2 was treated with NHC→SiCl4. In acetonitrile, the cationic silicon(IV) complexes [(NHC)SiCl3]+ and [(NHC)2SiCl3]+ were detected with [(C2F5)SiCl3]− as counterion. A similar result was already reported for the reaction of NHC→SiCl4 with (C2F5)2SiH2, which gave [(NHC)2SiCl2H][(C2F5)SiCl3]. If the reaction medium was changed to dichloromethane, the products of carbene transfer, NHC→Si(C2F5)2Cl2 and NHC→Si(C2F5)2ClH, respectively, were obtained instead. The formation of the latter species is a result of chloride/hydride metathesis. These compounds may serve as valuable precursors for electron‐poor silylenes. Furthermore, the reactivity of NHC→SiCl4 towards phosphines is discussed. The carbene complex NHC→PCl3 shows similar reactivity to NHC→SiCl4, and may even serve as a carbene‐transfer reagent as well.
A Selective and Sensitive Phenanthroimidazole‐Based “Reactive” Ratiometric Sensor for Recognition of Hg2+ Ions in Aqueous Solution
Authors: Yan Yuanyuan , Zhang Rui , Yu Xiang , Xu Hui 
Published: October 2014

AbstractBased on specific reactivity of the vinyloxy group to Hg2+ ions, a new ratiometric phenanthroimidazole‐based fluorescent sensor, 2‐(2‐(vinyloxy)phenyl)‐1 H‐phenanthro[9,10‐d]imidazole, is prepared. The selectivity of the probe toward Hg2+ ions is very high, and shows minimal interference from other commonly coexistent metal ions. The reactive stoichiometry of the probe with Hg2+ ion is 2:1. Its detection limit is evaluated and Hg2+ ions can be detected down to a lower limit of 2.5×10−8 M. Moreover, the Hg2+‐promoted selective hydrolysis of a vinyloxy group of the probe is further confirmed by 1H NMR spectroscopy and mass spectrometry.
Experimental evidence of the photonic bandgap and defect effect in Si‐SiO2 multilayer structures
Authors: Bouaziz L. , Nachi K. , Gamra D. , Lejeune M. , Zeinert A. , Zellama K. , Bouchriha H. 
Published: October 2014

We have elaborated a one dimensional photonic crystal (Si/SiO2) by depositing alternative silicon and silica layers by radiofrequency magnetron sputtering technique with cold plasma. After optimising the layer thickness to get good transmission, we studied the effect of the crystal layers number on the transmission and reflection spectra. We have shown that the photonic bandgap appears after five alternating Si and SiO2 layers and is well structured after nine alternating layers with a pseudo‐band gap of 1.75 eV. We have also introduced a defect in the structure by changing the thickness of one Si layer, than of one SiO2 layer, in the middle of the structure and observed a corresponding defect mode frequency. Using a theoretical model based on the Plane Wave Expansion method and an appropriate code calculation, we have shown that to have a better defined photonic bandgap, the most appropriate number of periods of the alternating layers should be higher than ten and corresponds to a photonic bandgap of 1.60 eV. We have also theoretically reproduced the experimental transmission and reflection spectra with good agreement.