bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanism and Origin of Selectivity in Platinum(II)‐Catalyzed Reactions of Acyclic γ,δ‐Ynones with Alkenes
Authors: Zhang Sujuan , Lv Pingli , Jia Chuanyi , Zhu Rongxiu , Lu Tongxiang , Wheeler Steven E. 
Published: August 2016

AbstractThe generation of platinum‐containing carbonyl ylides from acyclic γ,δ‐ynones and the cycloaddition of these ylides with electron‐rich alkenes have been explored computationally to explain the experimentally observed regio‐ and stereoselectivity. Three pathways for the reaction of ylides with methyl vinyl ether have been investigated. Two of these involve [3+2] cycloadditions, whereas the third involves a [4+2] cycloaddition. Results indicate that the operative reaction pathway depends on the substitution pattern of the acyclic γ,δ‐ynone. For an acyclic γ,δ‐ynone without a methyl substituent at the propargylic position, we predict that both [3+2] cycloaddition pathways are more favorable than the [4+2] cycloaddition pathway, which leads to two products. On the other hand, for an acyclic γ,δ‐ynone with a methyl substituent at the propargylic position, one of the [3+2] pathways is predicted to dominate, which exclusively affords an exo product. This feature arises from the hyperconjugative stabilization effect of the methyl group. Further analysis indicates that steric interactions between the chlorine atom of the catalyst and the methyl group of the vinyl ether lead to the observed exo selectivity. In all cases, the cycloaddition is the rate determining step, whereas for chiral PtCl2(bisphosphine)‐catalyzed reactions it is also stereodetermining, the high degree of enantioselectivity arises from differences in both noncovalent dispersion interactions and extent of partial bond formation in the key transition states for the [3+2] cycloaddition.
Ytterbium(III) Trifluoromethanesulfonate Catalyzed Ring‐Opening C(sp3)−N Bond Formation of Benzoxazoles with Propargylic Alcohols
Authors: Liu Wenfei , Sun Yongqing , Zhao Haiying , Li Baoguo , Chen Shufeng 
Published: August 2016

AbstractA novel ytterbium(III) trifluoromethanesulfonate [Yb(OTf)3]‐catalyzed ring‐opening C(sp3)−N bond formation reaction of benzoxazole with propargylic alcohols was established. This reaction uses readily available starting materials and is operationally simple; it thus represents a practical method for the construction of highly functionalized substituted benzenes bearing aldehyde, propargylamine, and hydroxy groups with high atom economy.
Between Adamantane and Atrane: Intrabridgehead Interactions in the Cage‐Like Phosphane Related to a Novel Tris(homoadamantane) Ring System
Authors: Britvin Sergey N. , Rumyantsev Andrey M. , Zobnina Anastasia E. , Padkina Marina V. 
Published: August 2016

AbstractHerein, we report unusual four‐center interactions in the novel cage‐like phosphane, 1,4,7‐triaza‐9‐phosphatricyclo[5.3.2.14,9]tridecane (CAP). This water‐soluble ligand, the first example of a tris(homoadamantane) ring system, can be considered a macrocyclic homologue of the well‐known PTA (1,3,5‐triaza‐7‐phosphaadamantane). However,31P NMR spectroscopic anomalies of CAP follow those typical for the bi‐/tricyclic atrane systems. Another atrane‐like feature of CAP is the ability of one nitrogen atom to undergoout–inpyramidal inversion. The latter is associated with a substantial decrease in the intracage N−N and P−N distances. Analysis of electron density distribution [molecular electrostatic potential (MESP) and atoms‐in‐molecules (AIM) approaches] suggests that the P and N atoms in the pyramidally inverted CAP derivatives are involved in interactions resulting in accumulation of electron density at the center of the phosphane cage. The latter can reliably explain the stereoelectronic and NMR anomalies of the new ligand. The semi‐flexible CAP cage populates the structural niche between the rigid adamantine skeleton of PTA and flexible atrane systems and can be regarded as an alternative to PTA in aqueous coordination chemistry.
Unprecedented Double aza‐Michael Addition within a Sapphyrin Core
Authors: Figueira Flávio , Marques Igor , Farinha Andreia S. F. , Tomé Augusto C. , Cavaleiro José A. S. , Silva Artur M. S. , Sessler Jonathan , Félix Vítor , Tomé João P. C. 
Published: August 2016

AbstractA novel sapphyrin derivative was obtained from the reaction between a free‐base sapphyrin and dimethyl acetylenedicarboxylate (DMAD). The formation of the new compound involved a double aza‐Michael addition of two pyrrolic NH groups to a DMAD molecule, with the formation of a disubstituted ethano bridge. The NMR spectral data reveal a product with an unsymmetrical structure; DFT calculations provided support for a structure in which the ethano bridge links two adjacent pyrrole units. The present study provides a seemingly unprecedented example of an N,N′‐dinucleophile reacting with DMAD to form a heterocyclic compound in which the two N‐atoms are linked to the two sp3 carbon atoms derived from a substituted acetylene.
A Stable Extra‐Large‐Pore Zeolite with Intersecting 14‐ and 10‐Membered‐Ring Channels
Authors: Gao Zi‐Hao , Chen Fei‐Jian , Xu Lei , Sun Lin , Xu Yan , Du Hong‐Bin 
Published: August 2016

AbstractThe development of inorganic frameworks with extra‐large pores (larger than 12‐membered rings) has attracted considerable attention because of their potential applications in catalysis, the separation of large molecules, and so forth. We herein report the synthesis of the new extra‐large‐pore zeolite NUD‐2 by using the supramolecular self‐assembly of simple aromatic organic cations as structure‐directing agents (SDAs). NUD‐2 is a high‐silicon‐content germanosilicate with interconnecting 14×10‐membered‐ring channels. The SDAs in NUD‐2 can be removed by calcination in air at 550 °C to yield permanent pores with a BET surface area of 500 m2g−1. Both germanium and organic cations in NUD‐2 can also be removed by treatment with acid at lower temperature, thus not only affording recycling of germanium and SDAs, but also providing a highly stable siliceous zeolite. In addition, aluminum ions can be incorporated into the framework of NUD‐2. The NUD‐2 structure is yet another extra‐large‐pore zeolite synthesized by using the supramolecular self‐assembling templating approach, thus demonstrating that this approach is a general and applicable strategy for synthesis of new large‐ and extra‐large‐pore zeolites.
Iterative method for frequency domain identification of continuous processes with delay time
Authors: Jin Qibing , He En , Wang Qi , Jiang Beiyan 
Published: August 2016

AbstractDelay time that affects the performances of many control synthesis techniques in controlled systems is common in most chemical industries. Estimating the delay time is also a difficult problem in identification fields. In this paper, aiming at continuous processes with delay time, an iterative least square identification method is proposed in the frequency domain. By introducing a truncated first‐order Taylor expansion, the delay time term is linearized. Linear regression equation for least squares (LS) is directly derived from the transfer function whose nonlinear term is replaced by a linear one. For reducing the linear approximation error and getting more accurate estimations of the model parameters, an iterative algorithm is developed based on the LS. Moreover, the proposed method can be easily extended to a closed‐loop system without increasing the order of the identified model. Simulations verify the effectiveness, fast convergence rates, and robustness of the proposed identification algorithm.
Disparate clinical activity of PD‐1 blockade in melanoma subtypes: Know thy enemy!
Authors: Bhatia Shailender , Margolin Kim 
Published: August 2016

The 2 articles by Shousatri et al and Algazi et al in this issue of Cancer report the efficacy of programmed cell death receptor 1 (PD‐1) pathway blockade in metastatic acral/mucosal melanoma and uveal melanoma, respectively. The results point to the disparate activity of PD‐1 and PD‐1 ligand pathway blockade in these subtypes of melanoma and highlight the need to understand differences in the underlying biology of immune evasion in these and other malignancies as well as the need to identify mechanisms of success and failure of PD‐1 blockade.See also pages 3344‐53 and 3354‐62.
Sexuality after a cancer diagnosis: A population‐based study
Authors: Jackson Sarah E. , Wardle Jane , Steptoe Andrew , Fisher Abigail 
Published: August 2016

BACKGROUNDThis study explored differences in sexual activity, function, and concerns between cancer survivors and cancer‐free controls in a population‐based study.METHODSThe data were from 2982 men and 3708 women who were 50 years old or older and were participating in the English Longitudinal Study of Ageing. Sexual well‐being was assessed with the Sexual Relationships and Activities Questionnaire, and cancer diagnoses were self‐reported.RESULTSThere were no differences between cancer survivors and controls in levels of sexual activity (76.0% vs 78.5% for men and 58.2% vs 55.5% for women) or sexual function. Men and women with cancer diagnoses were more dissatisfied with their sex lives than controls (age‐adjusted percentages: 30.9% vs 19.8% for men [P = .023] and 18.2% vs 11.8% for women [P = .034]), and women with cancer were more concerned about levels of sexual desire (10.2% vs 7.1%; P = .006). Women diagnosed < 5 years ago were more likely to report difficulty with becoming aroused (55.4% vs 31.8%; P = .016) and achieving orgasm (60.6% vs 28.3%; P < .001) and were more concerned about sexual desire (14.8% vs 7.1%; P = .007) and orgasmic experience (17.6% vs 7.1%; P = .042) than controls, but there were no differences in men.CONCLUSIONSSelf‐reports of sexual activity and functioning in older people with cancer are broadly comparable to age‐matched, cancer‐free controls. There is a need to identify the causes of sexual dissatisfaction among long‐term cancer survivors despite apparently normal levels of sexual activity and function for their age. The development of interventions addressing low sexual desire and problems with sexual functioning in women is also important and may be particularly relevant for cancer survivors after treatment. Cancer 2016;122:3883–3891. © 2016 American Cancer Society.
Effect of Food and Esomeprazole on the Pharmacokinetics of Alectinib, a Highly Selective ALK Inhibitor, in Healthy Subjects
Authors: Morcos Peter N. , Guerini Elena , Parrott Neil , Dall Georgina , Blotner Steven , Bogman Katrijn , Sturm Carolina , Balas Bogdana , Martin‐Facklam Meret , Phipps Alex 
Published: August 2016

AbstractAlectinib, an anaplastic lymphoma kinase (ALK) inhibitor, is approved for treatment of patients with ALK+ non–small cell lung cancer who have progressed, on or are intolerant to, crizotinib. This study assessed the effect of a high‐fat meal and the proton pump inhibitor, esomeprazole, on the pharmacokinetics (PK) of alectinib. This was an open‐label, 2‐group study in healthy subjects. In group 1 (n = 18), subjects were randomly assigned to a 2‐treatment (A, fasted conditions; B, following a high‐fat meal), 2‐sequence (AB or BA) crossover assessment, separated by a 10‐day washout. In group 2 (n = 24), subjects were enrolled in a 2‐period, fixed‐sequence crossover assessment to evaluate the effect of esomeprazole. PK parameters were evaluated for alectinib, its major similarly active metabolite, M4, and the combined exposure of alectinib and M4. Administration of alectinib following a high‐fat meal substantially increased the combined exposure of alectinib and M4 to 331% (90%CI, 279%–393%) and 311% (90%CI, 273%–355%) for Cmax and AUC0–∞, respectively, versus fasted conditions. Coadministration of esomeprazole had no clinically relevant effect on the combined exposure of alectinib and M4. Alectinib should be administered under fed conditions to maximize its bioavailability, whereas no restrictions are required with antisecretory agents.
Tracing the Fingerprint of Chemical Bonds within the Electron Densities of Hydrocarbons: A Comparative Analysis of the Optimized and the Promolecule Densities
Authors: Keyvani Zahra Alimohammadi , Shahbazian Shant , Zahedi Mansour 
Published: August 2016

AbstractThe equivalence of the molecular graphs emerging from the comparative analysis of the optimized and the promolecule electron densities in two hundred and twenty five unsubstituted hydrocarbons was recently demonstrated [Keyvani et al.Chem. Eur. J.2016,22, 5003]. Thus, the molecular graph of an optimized molecular electron density is not shaped by the formation of the C−H and C−C bonds. In the present study, to trace the fingerprint of the C−H and C−C bonds in the electron densities of the same set of hydrocarbons, the amount of electron density and its Laplacian at the (3, −1) critical points associated with these bonds are derived from both optimized and promolecule densities, and compared in a newly proposed comparative analysis. The analysis not only conforms to the qualitative picture of the electron density build up between two atoms upon formation of a bond in between, but also quantifies the resulting accumulation of the electron density at the (3, −1) critical points. The comparative analysis also reveals a unified mode of density accumulation in the case of 2318 studied C−H bonds, but various modes of density accumulation are observed in the case of 1509 studied C−C bonds and they are classified into four groups. The four emerging groups do not always conform to the traditional classification based on the bond orders. Furthermore, four C−C bonds described as exotic bonds in previous studies, for example the inverted C−C bond in 1,1,1‐propellane, are naturally distinguished from the analysis.
ZnO Nanostructures for Dye‐Sensitized Solar Cells Using the TEMPO+/TEMPO Redox Mediator and Ruthenium(II) Photosensitizers with 1,2,3‐Triazole‐Derived Ligands
Authors: Wahyuono Ruri Agung , Schulze Benjamin , Rusu Mihai , Wächtler Maria , Dellith Jan , Seyring Martin , Rettenmayr Markus , Plentz Jonathan , Ignaszak Anna , Schubert Ulrich S. , Dietzek Benjamin 
Published: August 2016

AbstractA series of thiocyanate‐free bis(tridentate) ruthenium(II) complexes incorporating 1,2,3‐triazole‐derived NNN‐, NCN‐, and CNC‐coordinating ligands has been employed for sensitizing ZnO photoanodes for dye‐sensitized solar cells (DSSCs). Additionally, the first use of the TEMPO+/TEMPO (2,2,6,6‐tetramethyl‐piperidine‐1‐oxyl) redox mediator as a surrogate for the I3−/I− redox couple in ZnO nanostructured DSSCs is presented. Compared with I3−/I−‐based electrolytes, shorter charge lifetimes and diffusion lengths were determined for the TEMPO+/TEMPO‐based electrolyte. Nonetheless, similar power conversion efficiencies (PCEs) were achieved with both electrolytes for the RuNCN and RuCNC complexes, whereas higher PCEs are enabled by the iodine‐free electrolyte in case of RuNNN. The combination of the molecular sensitizers and the TEMPO‐based electrolyte exhibits relatively high external quantum efficiency (EQE) and promising PCEs, ranging from 4.48 to 1.47 %, which are—in part—comparable to that of ZnO‐DSSCs with the benchmark N749 black dye. The TEMPO‐based electrolyte also exhibits less absorption compared with its I3−/I− counterpart, a favorable feature for enhancing the light harvesting ability of the photoanode. Furthermore, the results show the effect of the dye‐sensitization procedure on the PCE values: The use of ethanol as the solvent compared with methanol increases the DSSC's efficiency, which is attributed to improved chemisorption of the sensitizer onto the ZnO surface.
Self‐Cloning CRISPR
Authors: Arbab Mandana , Sherwood Richard I. 
Published: August 2016

AbstractCRISPR/Cas9‐gene editing has emerged as a revolutionary technology to easily modify specific genomic loci by designing complementary sgRNA sequences and introducing these into cells along with Cas9. Self‐cloning CRISPR/Cas9 (scCRISPR) uses a self‐cleaving palindromic sgRNA plasmid (sgPal) that recombines with short PCR‐amplified site‐specific sgRNA sequences within the target cell by homologous recombination to circumvent the process of sgRNA plasmid construction. Through this mechanism, scCRISPR enables gene editing within 2 hr once sgRNA oligos are available, with high efficiency equivalent to conventional sgRNA targeting: >90% gene knockout in both mouse and human embryonic stem cells and cancer cell lines. Furthermore, using PCR‐based addition of short homology arms, we achieve efficient site‐specific knock‐in of transgenes such as GFP without traditional plasmid cloning or genome‐integrated selection cassette (2% to 4% knock‐in rate). The methods in this paper describe the most rapid and efficient means of CRISPR gene editing. © 2016 by John Wiley & Sons, Inc.
Comprehensive Protocols for CRISPR/Cas9‐based Gene Editing in Human Pluripotent Stem Cells
Authors: Santos David P. , Kiskinis Evangelos , Eggan Kevin , Merkle Florian T. 
Published: August 2016

AbstractGenome editing of human pluripotent stem cells (hPSCs) with the CRISPR/Cas9 system has the potential to revolutionize hPSC‐based disease modeling, drug screening, and transplantation therapy. Here, we aim to provide a single resource to enable groups, even those with limited experience with hPSC culture or the CRISPR/Cas9 system, to successfully perform genome editing. The methods are presented in detail and are supported by a theoretical framework to allow for the incorporation of inevitable improvements in the rapidly evolving gene‐editing field. We describe protocols to generate hPSC lines with gene‐specific knock‐outs, small targeted mutations, or knock‐in reporters. © 2016 by John Wiley & Sons, Inc.
Neural Stem Cell or Human Induced Pluripotent Stem Cell–Derived GABA‐ergic Progenitor Cell Grafting in an Animal Model of Chronic Temporal Lobe Epilepsy
Authors: Upadhya Dinesh , Hattiangady Bharathi , Shetty Geetha A. , Zanirati Gabriele , Kodali Maheedhar , Shetty Ashok K. 
Published: August 2016

AbstractGrafting of neural stem cells (NSCs) or GABA‐ergic progenitor cells (GPCs) into the hippocampus could offer an alternative therapy to hippocampal resection in patients with drug‐resistant chronic epilepsy, which afflicts >30% of temporal lobe epilepsy (TLE) cases. Multipotent, self‐renewing NSCs could be expanded from multiple regions of the developing and adult brain, human embryonic stem cells (hESCs), and human induced pluripotent stem cells (hiPSCs). On the other hand, GPCs could be generated from the medial and lateral ganglionic eminences of the embryonic brain and from hESCs and hiPSCs. To provide comprehensive methodologies involved in testing the efficacy of transplantation of NSCs and GPCs in a rat model of chronic TLE, NSCs derived from the rat medial ganglionic eminence (MGE) and MGE‐like GPCs derived from hiPSCs are taken as examples in this unit. The topics comprise description of the required materials, reagents and equipment, methods for obtaining rat MGE‐NSCs and hiPSC‐derived MGE‐like GPCs in culture, generation of chronically epileptic rats, intrahippocampal grafting procedure, post‐grafting evaluation of the effects of grafts on spontaneous recurrent seizures and cognitive and mood impairments, analyses of the yield and the fate of graft‐derived cells, and the effects of grafts on the host hippocampus. © 2016 by John Wiley & Sons, Inc.
A Copper Porphyrin‐Based Conjugated Mesoporous Polymer‐Derived Bifunctional Electrocatalyst for Hydrogen and Oxygen Evolution
Authors: Cui Shengsheng , Qian Manman , Liu Xiang , Sun Zijun , Du Pingwu 
Published: August 2016

AbstractScalable and robust catalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are required for the implementation of water splitting technologies as a globally applicable method of producing renewable hydrogen. Herein, we report nitrogen‐enriched porous carbon materials containing copper/copper oxide, derived from copper porphyrin‐based conjugated mesoporous polymers (CMPs), as a bifunctional catalyst for both HER and OER. These catalysts have a high surface area, unique tubular structure, and strong synergistic effect of copper/copper oxide and porous carbons, resulting in excellent performance for water splitting. Under optimal conditions, the catalyst exhibits a quite low overpotential for OER (350 mV to reach 1.0 mA cm−2 and 450 mV to reach 10 mA cm−2) in alkaline media, which places it among the best copper‐based water oxidation catalysts reported in the literature. Furthermore, the catalyst shows good catalytic activity for HER at a low overpotential (190 mV to reach 1.0 mA cm−2) as well as a high current density (470 mV to reach 50 mA cm−2). The results suggest that hybridized copper/carbon materials are attractive noble‐metal‐free catalysts for water splitting.
High‐Capacity Layered‐Spinel Cathodes for Li‐Ion Batteries
Authors: Nayak Prasant Kumar , Levi Elena , Grinblat Judith , Levi Mikhael , Markovsky Boris , Munichandraiah N. , Sun Yang Kook , Aurbach Doron 
Published: August 2016

AbstractLi and Mn‐rich layered oxides with the general structure x Li2MnO3⋅(1–x) LiMO2 (M=Ni, Mn, Co) are promising cathode materials for Li‐ion batteries because of their high specific capacity, which may be greater than 250 mA h g−1. However, these materials suffer from high first‐cycle irreversible capacity, gradual capacity fading, limited rate capability and discharge voltage decay upon cycling, which prevent their commercialization. The decrease in average discharge voltage is a major issue, which is ascribed to a structural layered‐to‐spinel transformation upon cycling of these oxide cathodes in wide potential ranges with an upper limit higher than 4.5 V and a lower limit below 3 V versus Li. By using four elements systems (Li, Mn, Ni, O) with appropriate stoichiometry, it is possible to prepare high capacity composite cathode materials that contain LiMn1.5Ni0.5O4 and LixMnyNizO2 components. The Li and Mn‐rich layered‐spinel cathode materials studied herein exhibit a high specific capacity (≥200 mA h g−1) with good capacity retention upon cycling in a wide potential domain (2.4–4.9 V). The effect of constituent phases on their electrochemical performance, such as specific capacity, cycling stability, average discharge voltage, and rate capability, are explored here. This family of materials can provide high specific capacity, high rate capability, and promising cycle life. Using Co‐free cathode materials is also an obvious advantage of these systems.
A low complexity pre‐distortion scheme for power amplifier linearization in wideband applications
Authors: Varahram Pooria , Dooley John , Finnerty Keith , Farrell Ronan 
Published: August 2016

SummaryIn this paper, a nonlinear autoregressive with exogenous inputs (NARX) digital pre‐distortion scheme to linearize power amplifiers is proposed. The proposed NARX digital pre‐distortion gives better accuracy and spectral leakage suppression compared with other commonly used Volterra‐based techniques. The stability criterion of the NARX digital pre‐distortion is derived from the frequency domain analysis. Simulation is carried out with a 20 MHz single carrier long‐term evolution signal and two‐carrier long‐term evolution signal and instantaneous to average ratio of 6.2 dB at 0.01% complementary cumulative distribution function (CCDF). The results of simulation analysis show a slight improvement in adjacent channel leakage ratio performance with 30% reduction in the number of floating point operations compared with conventional pre‐distortion techniques. Copyright © 2016 John Wiley & Sons, Ltd.