bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rhenium(I) Polypyridine Diamine Complexes as Intracellular Phosphorogenic Sensors: Synthesis, Characterization, Emissive Behavior, Biological Properties, and Nitric Oxide Sensing
Authors: Choi Alex Wing‐Tat , Yim Vicki Man‐Wai , Liu Hua‐Wei , Lo Kenneth Kam‐Wing 
Published: July 2014

AbstractWe report the development of a series of rhenium(I) polypyridine complexes appended with an electron‐rich diaminoaromatic moiety as phosphorogenic sensors for nitric oxide (NO). The diamine complexes [Re(N^N)(CO)3(py‐DA)][PF6] (py‐DA=3‐(N‐(2‐amino‐5‐methoxyphenyl)aminomethyl)pyridine; N^N=1,10‐phenanthroline (phen) (1 a), 3,4,7,8‐tetramethyl‐1,10‐phenanthroline (Me4‐phen) (2 a), 4,7‐diphenyl‐1,10‐phenanthroline (Ph2‐phen) (3 a)) have been synthesized and characterized. In contrast to common rhenium(I) diimines, these diamine complexes were very weakly emissive due to quenching of the triplet metal‐to‐ligand charge‐transfer (3MLCT) emission by the diaminoaromatic moiety through photoinduced electron transfer (PET). Upon treatment with NO, the complexes were converted into the triazole derivatives [Re(N^N)(CO)3(py‐triazole)][PF6] (py‐triazole=3‐((6‐methoxybenzotriazol‐1‐yl)methyl)pyridine; N^N=phen (1 b), Me4‐phen (2 b), Ph2‐phen (3 b)), resulting in significant emission enhancement (I/I0≈60). The diamine complexes exhibited high reaction selectivity to NO, and their emission intensity was found to be independent on pH. Also, these complexes were effectively internalized by HeLa cells and RAW264.7 macrophages with negligible cytotoxicity. Additionally, the use of complex 3 a as an intracellular phosphorogenic sensor for NO has been demonstrated.
Approach for the Preparation of Various Classes of Peroxides Based on the Reaction of Triketones with H2O2: First Examples of Ozonide Rearrangements
Authors: Yaremenko Ivan A. , Terent'ev Alexander O. , Vil' Vera A. , Novikov Roman A. , Chernyshev Vladimir V. , Tafeenko Viktor A. , Levitsky Dmitri O. , Fleury Fabrice , Nikishin Gennady I. 
Published: July 2014

AbstractThe reaction of β,δ‐triketones with an ethereal solution of H2O2 catalyzed by heteropoly acids in the presence of a polar aprotic co‐solvent proceeds via three pathways to form three classes of peroxides: tricyclic monoperoxides, bridged tetraoxanes, and a pair of stereoisomeric ozonides. The reaction is unusual in that produces bridged tetraoxanes and ozonides with one of the three carbonyl groups remaining intact. In the synthesis of bridged tetraoxanes, the peroxide ring is formed by the reaction of hydrogen peroxide with two carbonyl groups at the β positions. The synthesis of ozonides from ketones and hydrogen peroxide is a unique process in which the ozonide ring is formed with the participation of two carbonyl groups at the δ positions. Rearrangements of ozonides were found for the first time after more than one century of their active investigation. Ozonides are interconverted with each other and rearranged into tricyclic monoperoxides, whereas ozonides and tricyclic monoperoxides are transformed into bridged tetraoxanes. The individual reaction products were isolated by column chromatography and characterized by NMR spectroscopy, mass spectrometry, and elemental analysis. One representative of each class of peroxides was characterized by X‐ray diffraction.
A Theoretical Investigation of Photochemical Reactions of an Isolable Silylene with Benzene
Authors: Su Ming‐Der 
Published: July 2014

AbstractThe mechanisms of photochemical insertion reactions are investigated theoretically using the model system, an isolable dialkylsilylene and benzene, using the CAS(10,10)/6‐31G(d) and MP2‐CAS‐(10,10)/6‐311++G(df,pd)//CAS(10,10)/6‐31G(d) methods. The structures of the conical intersections, which play a key role in such photoinsertion reactions, are determined to provide a qualitative explanation of the reaction pathways. The model investigation demonstrates that the preferred reaction route for the isolable dialkylsilylene with benzene is as follows: reactants → Franck–Condon region → conical intersection → seven‐membered‐ring photoproduct. The theoretical findings suggest that the singlet excited dialkylsilylene should attack benzene in the perpendicular conformation, and that no silyl radicals should exist during these photoinsertion reactions. The results obtained allow a number of predictions to be made.
Palladium‐Catalyzed Carbonylative α‐Arylation to β‐Ketonitriles
Authors: Schranck Johannes , Burhardt Mia , Bornschein Christoph , Neumann Helfried , Skrydstrup Troels , Beller Matthias 
Published: July 2014

AbstractA carbonylative α‐arylation process employing unactivated nitriles for the first time is described. The reaction tolerates a range of (hetero)aryl iodides and several nitrile coupling partners. No prefunctionalization of the nitriles is necessary and the resulting β‐ketonitriles are obtained in good to excellent yields. The methodology also allows for a convenient 13C‐labelling of the generated carbonyl moiety.
Characterization of Silver and Fluorescent Dyes Incorporated in Self‐Assembling Peptides and Their Potential Applications in Biology
Authors: Subbalakshmi Chivukula , Nagaraj Ramakrishnan 
Published: July 2014

AbstractThere is increasing interest in studying the interaction of nanoparticles with biomolecules, microorganisms, and noble metals to explore their unique properties and potential biological applications. The synthetic butyloxycarbonyl (Boc)‐protected methyl esters of peptides composed of only aliphatic amino acids (Boc‐Ile‐Ile‐OMe and Boc‐Leu‐Ile‐Ile‐OMe) self‐assembled into nanotubes and spheres, respectively, has been previously demonstrated. Herein, the characterization of these peptide nanoparticles incorporated with silver by means of various spectrometric methods and electron microscopy imaging techniques is described. The antibacterial activity of Ag‐doped nanoparticles was determined. These peptide nanoparticles were demonstrated to be useful encapsulants of charged fluorescent dyes. This investigation demonstrates the potential of these short peptide nanoparticles to design formulations of antimicrobial agents that will enhance their activity and as fluorescent probes for cell imaging.
Diels–Alder Reaction of o‐Carboryne with Fulvenes: Synthesis of Carboranonorbornadienes and Their Transformations
Authors: Zhang Jie , Qiu Zaozao , Xu Peng‐Fei , Xie Zuowei 
Published: July 2014

Abstracto‐Carboryne (1,2‐dehydro‐o‐carborane) generated in situ from the precursor 1‐iodo‐2‐lithio‐o‐carborane reacts with 6,6′‐diarylfulvenes to give a series of carboranonorbornadienes in moderate yields with excellent regioselectivity. The resultant [4+2] cycloadducts can be further derivatized, thus leading to the formation of a variety of highly functionalized carboranes. This study shows that such Diels–Alder reaction serves as a convenient method for the preparation of a new class of multifunctionalized o‐carborane derivatives that might find applications in medicine and materials science.
Heterogeneous Catalysis and the Challenges of Powering the Planet, Securing Chemicals for Civilised Life, and Clean Efficient Utilization of Renewable Feedstocks
Authors: Thomas John Meurig 
Published: July 2014

AbstractThis article reviews, first, the prospects, practices and principles of generating solar fuels. It does so with an analysis of recent progress in the light‐driven emission of H2 (and other fuels) as well as O2 from water. To place this challenge in perspective, some current practices entailing the use of well‐proven solid catalysts developed for fossil‐based feedstocks, are described. The massive differences between proven methods of generating fuel and chemicals from non‐renewable and from solar radiation are emphasized with the aid of numerous quantitative examples. Whilst it is acknowledged that a key action in reducing the liberation of greenhouse gases (GHG) is to tackle the challenge of decreasing their evolution in power generation and in the production of steel, aluminium and other bulk commodities (metals, alloys, concrete and ceramics), nevertheless much can be done to diminish the emission of CO2 (and to use it as feedstock) through the agency of new, designed solid catalysts and microalgae. Solar‐thermal converters are also attractive alternatives, even though they are more likely to be used centrally rather than in small modular units like ‘artificial leaves,’ some of which are promising for the purposes of generating energy (and perhaps fuel) in a delocalized, modular manner.
Enhanced Performance and Stability of Polymer BHJ Photovoltaic Devices from Dry Transfer of PEDOT:PSS
Authors: Kim Jung Kyu , Park Insun , Kim Wanjung , Wang Dong Hwan , Choi Dae‐Geun , Choi Yeong Suk , Park Jong Hyeok 
Published: July 2014

AbstractPolymer solar cells with enhanced initial cell performances and long‐term stability were fabricated by performing a simple dry transfer of a hole extraction layer [poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)] onto an indium tin oxide (ITO) substrate. Due to the very flat surface of the polyurethane acrylate/polycarbonate (PUA/PC) film, which was used as a mold and resembled the surface of the original substrate (silicon wafer), the transferred layer had a very smooth surface morphology, resulting in enhancement of the interfacial characteristics. The work function of the PEDOT:PSS layer and the morphology of bulk hetero junction (BHJ) layer were tuned by controlling the position of PSS enrichment in the PEDOT:PSS layer using the dry transfer. The power conversion efficiency of PTB7:PC71BM BHJ device prepared by the dry transfer was 8.06 %, which was significantly higher than that of the spin‐cast device (7.32 %). By avoiding direct contact between the ITO substrate and the PEDOT:PSS solution in the dry transfer system, etching and diffusion of indium in the ITO substrate were greatly reduced, thereby improving the stability.
An evolutionary perspective on leaf economics: phylogenetics of leaf mass per area in vascular plants
Authors: Flores Olivier , Garnier Eric , Wright Ian J. , Reich Peter B. , Pierce Simon , Dìaz Sandra , Pakeman Robin J. , Rusch Graciela M. , Bernard‐Verdier Maud , Testi Baptiste , Bakker Jan P. , Bekker Renée M. , Cerabolini Bruno E. L. , Ceriani Roberta M. , Cornu Guillaume , Cruz Pablo , Delcamp Matthieu , Dolezal Jiri , Eriksson Ove , Fayolle Adeline , Freitas Helena , Golodets Carly , Gourlet‐Fleury Sylvie , Hodgson John G. , Brusa Guido , Kleyer Michael , Kunzmann Dieter , Lavorel Sandra , Papanastasis Vasilios P. , Pérez‐Harguindeguy Natalia , Vendramini Fernanda , Weiher Evan 
Published: July 2014

AbstractIn plant leaves, resource use follows a trade‐off between rapid resource capture and conservative storage. This “worldwide leaf economics spectrum” consists of a suite of intercorrelated leaf traits, among which leaf mass per area, LMA, is one of the most fundamental as it indicates the cost of leaf construction and light‐interception borne by plants. We conducted a broad‐scale analysis of the evolutionary history of LMA across a large dataset of 5401 vascular plant species. The phylogenetic signal in LMA displayed low but significant conservatism, that is, leaf economics tended to be more similar among close relatives than expected by chance alone. Models of trait evolution indicated that LMA evolved under weak stabilizing selection. Moreover, results suggest that different optimal phenotypes evolved among large clades within which extremes tended to be selected against. Conservatism in LMA was strongly related to growth form, as were selection intensity and phenotypic evolutionary rates: woody plants showed higher conservatism in relation to stronger stabilizing selection and lower evolutionary rates compared to herbaceous taxa. The evolutionary history of LMA thus paints different evolutionary trajectories of vascular plant species across clades, revealing the coordination of leaf trait evolution with growth forms in response to varying selection regimes.
Finding a home for plasma cells — A niche to survive
Authors: Tellier Julie , Kallies Axel 
Published: July 2014

Long‐term survival of plasma cells (PCs) and sustained antibody secretion require a specific microenvironment that provides the appropriate prosurvival signals. This plasma cell niche involves both mesenchymal and hematopoietic components. Although a consensus exists about the essential contribution of CXCL12+ stromal cells in this environment, the identity of the hematopoietic participants remains a matter of debate. In this issue of the European Journal of Immunology, Zehentmeier et al. [Eur. J. Immunol. 2014. 44: 2306‐2317] aim to identify the components of the bone marrow plasma cell niche in C57BL/6 mice in an unbiased manner by using a streamlined analysis of histological colocalization data. Apart from stromal cells, the authors showed that eosinophils are the only population specifically localized in the vicinity of PCs. In addition, the authors performed intravital imaging demonstrating that PCs are sessile and form stable contacts with reticular stromal cells. This work opens the door to a more rational approach to characterize the plasma cell niche.
Organometallic Approaches to Conjugated Polymers for Plastic Solar Cells: From Laboratory Synthesis to Industrial Production
Authors: Marzano Giuseppe , Ciasca Cosimo V. , Babudri Francesco , Bianchi Gabriele , Pellegrino Andrea , Po Riccardo , Farinola Gianluca M. 
Published: July 2014

AbstractAn overview of the organometallic synthetic approaches to low‐band‐gap polymers for organic solar cells from 2008 to the present is reported. The key role of the synthetic methods in development of materials with increasing performances is outlined, with consideration not only of research laboratory criteria, but also of parameters relevant to mass production: synthetic complexity, amount and toxicity of reactants and by‐products, and purification steps. The review is organized into sections covering the different organometallic polymerization reactions, also including olefin metathesis and the most recent results on direct arylation processes that appear particularly promising in terms of reduced synthetic complexity, costs, and byproducts. In the last section of the review, the discussed synthetic methods are reconsidered from the perspective of industrial scalability, which is one of the most critical issues for making OPV technology an effective route to solar energy exploitation. Interesting considerations are drawn on these basis, and directions for future developments in terms of requirements of the synthetic protocols are outlined.
Total Synthesis of (–)‐Heliespirone A and (+)‐Heliespirone C
Authors: Norcott Philip , McErlean Christopher S. P. 
Published: July 2014

AbstractTotal syntheses of the spiro‐epimeric natural products (–)‐heliespirone A and (+)‐heliespirone C are described. The successful strategy involved an aromatic Claisen rearrangement, a diastereoselective Sharpless asymmetric dihydroxylation (AD) reaction, and an intramolecular oxa‐Michael addition.
Characteristics of canonical intrinsic connectivity networks across tasks and monozygotic twin pairs
Authors: Moodie Craig A. , Wisner Krista M. , MacDonald Angus W. 
Published: July 2014

AbstractIntrinsic connectivity networks (ICNs) are becoming more prominent in the analyses of in vivo brain activity as the field of neurometrics has revealed their importance for augmenting traditional cognitive neuroscience approaches. Consequently, tools that assess the coherence, or connectivity, and morphology of ICNs are being developed to support inferences and assumptions about the dynamics of the brain. Recently, we reported trait‐like profiles of ICNs showing reliability over time and reproducibility across different contexts. This study further examined the trait‐like and familial nature of ICNs by utilizing two divergent task paradigms in twins. The study aimed to identify stable network phenotypes that exhibited sensitivity to individual differences and external perturbations in task demands. Analogous ICNs were detected in each task and these ICNs showed consistency in morphology and intranetwork coherence across tasks, whereas the ICN timecourse dynamics showed sensitivity to task demands. Specifically, the timecourse of an arm/hand sensorimotor network showed the strongest correlation with the timeline of a hand imitation task, and the timecourse of a language‐processing network showed the strongest temporal association with a verb generation task. The area V1/simple visual stimuli network exhibited the most consistency in morphology, coherence, and timecourse dynamics within and across tasks. Similarly, this network exhibited familiality in all three domains as well. Hence, this experiment is a proof of principle that the morphology and coherence of ICNs can be consistent both within and across tasks, that ICN timecourses can be differentially and meaningfully modulated by a task, and that these domains can exhibit familiality. Hum Brain Mapp 35:5532–5549, 2014. © 2014 Wiley Periodicals, Inc.
Payment Mechanisms and the Composition of Physician Practices: Balancing Cost‐Containment, Access, and Quality of Care
Authors: Barham Victoria , Milliken Olga 
Published: July 2014

SummaryWe take explicit account of the way in which the supply of physicians and patients in the economy affects the design of physician remuneration schemes, highlighting the three‐way trade‐off between quality of care, access, and cost. Both physicians and patients are heterogeneous. Physicians choose both the number of patients and the quality of care to provide to their patients. When determining physician payment rates, the principal must ensure access to care for all patients. When physicians can adjust the number of patients seen, there is no incentive to over‐treat. In contrast, altruistic physicians always quality stint: they prefer to add an additional patient, rather than to increase the quality of service provided. A mixed payment mechanism does not increase the quality of service provided with respect to capitation. Offering a menu of compensation schemes may constitute a cost‐effective strategy for inducing physicians to choose a given overall caseload but may also generate difficulties with access to care for frail patients. Copyright © 2014 John Wiley & Sons, Ltd.
Personnel Selection Using Interval 2‐Tuple Linguistic VIKOR Method
Authors: Liu Hu‐Chen , Qin Jiang‐Tao , Mao Ling‐Xiang , Zhang Zhi‐Ying 
Published: July 2014

AbstractPersonnel selection is a very important activity in the human resource management of an organization. However, in many practical circumstances, due to time pressure and lack of information about candidates, decision makers generally tend to provide linguistic assessments and use different linguistic term sets to express their opinions during the personnel selection process. In this article, the VIKOR method combined with interval 2‐tuple linguistic variables is proposed to choose appropriate individuals among candidates in a group decision‐making environment. The interval 2‐tuple linguistic variable, which comprises two linguistic terms and two real numbers, is more flexible and precise to deal with linguistic information in solving personnel selection problems. To demonstrate the applicability and effectiveness of the proposed interval 2‐tuple linguistic VIKOR method, a numerical example of personnel selection in a tertiary care hospital is provided.
Selective inhibition of miR‐92 in hippocampal neurons alters contextual fear memory
Authors: Vetere Gisella , Barbato Christian , Pezzola Silvia , Frisone Paola , Aceti Massimiliano , Ciotti MariaTeresa , Cogoni Carlo , Ammassari‐Teule Martine , Ruberti Francesca 
Published: July 2014

ABSTRACTPost‐transcriptional gene regulation mediated by microRNAs (miRNAs) is implicated in memory formation; however, the function of miR‐92 in this regulation is uncharacterized. The present study shows that training mice in contextual fear conditioning produces a transient increase in miR‐92 levels in the hippocampus and decreases several miR‐92 gene targets, including: (i) the neuronal Cl‐ extruding K+Cl‐ co‐transporter 2 (KCC2) protein; (ii) the cytoplasmic polyadenylation protein (CPEB3), an RNA‐binding protein regulator of protein synthesis in neurons; and (iii) the transcription factor myocyte enhancer factor 2D (MEF2D), one of the MEF2 genes which negatively regulates memory‐induced structural plasticity. Selective inhibition of endogenous miR‐92 in CA1 hippocampal neurons, by a sponge lentiviral vector expressing multiple sequences imperfectly complementary to mature miR‐92 under the control of the neuronal specific synapsin promoter, leads to up‐regulation of KCC2, CPEB3 and MEF2D, impairs contextual fear conditioning, and prevents a memory‐induced increase in the spine density. Taken together, the results indicate that neuronal‐expressed miR‐92 is an endogenous fine regulator of contextual fear memory in mice. © 2014 Wiley Periodicals, Inc.
Understanding the shortage of village doctors in China and solutions under the policy of basic public health service equalization: evidence from Changzhou
Authors: Li Xiaohong , Cochran Christopher , Lu Jun , Shen Jay , Hao Chao , Wang Ying , Sun Mei , Li Chengyue , Chang Fengshui , Hao Mo 
Published: July 2014

SummaryAs the most important public health service providers in rural China, village doctors are facing a new challenge of heavier workload resulting from the recent policy of public health service equalization. Studies on the shortage of village doctors, mainly based on the national statistics, have so far been very broad. This study conducted detailed field surveys to identify specific factors of and potential solutions to the shortage in village doctors.Eight hundred forty‐four village doctors and 995 health decision makers and providers were surveyed through a questionnaire, and some of them were surveyed by in‐depth face‐to‐face interviews and focus group interviews. Opinions on the shortage in village doctors and the potentially effective approaches to addressing the problem were sought.Some village doctors (51.3%) were at least 50 years old.Some village doctors (92.3%) did not want their children to become a village doctor, and the main reasons were “low salary” and “lack of social security”. Village doctors felt that it was difficult to provide all the required public health services. Local residents indicated that they established good relationships with village doctors. Some health decision makers and providers (74.0%) thought that they needed more village doctors.The shortage in village doctors presents a major obstacle toward the realization of China's policy of public health service equalization. The aging of current village doctors exacerbates the problem. Policies and programs are needed to retain the current and attract new village doctors into the workforce. Separate measures are also needed to address disparities in socioeconomic circumstance from village to village. Copyright © 2014 John Wiley & Sons, Ltd.
On the Role of Physics and Evolution in Dictating Protein Structure and Function
Authors: Skolnick Jeffrey , Gao Mu , Zhou Hongyi 
Published: July 2014

AbstractHow many of the structural and functional properties of proteins are inherent? Computer simulations provide a powerful tool to address this question. A series of studies on three libraries of proteinsQS, quasi‐spherical, compact polypeptides that lack any secondary structure; ART, artificial proteins comprised of compact homopolypeptides with protein‐like secondary structures; and PDB, native, single‐domain proteinsshows that essentially all native global folds, pockets, and protein‐protein interfaces are in the ART library. This suggests that many protein properties are inherent and that evolution is involved in fine‐tuning. The completeness of the space of ligand‐binding pockets and protein‐protein interfaces suggests that promiscuous interactions are intrinsic to proteins and that the capacity to perform the biochemistry of life at low level does not require evolution. If so, this has profound implications with regard to the origin of life.