bluuebunny/crossref_metadata_2025_split huggingface dataset:
Paintable Room‐Temperature Phosphorescent Liquid Formulations of Alkylated Bromonaphthalimide
Authors: Goudappagouda  , Manthanath Ananthakrishnan , Wakchaure Vivek Chandrakant , Ranjeesh Kayaramkodath Chandran , Das Tamal , Vanka Kumar , Nakanishi Takashi , Babu Sukumaran Santhosh 
Published: December 2018

AbstractOrganic phosphors have been widely explored with an understanding that crystalline molecular ordering is a requisite for enhanced intersystem crossing. In this context, we explored the room‐temperature phosphorescence features of a solvent‐free organic liquid phosphor in air. While alkyl chain substitution varied the physical states of the bromonaphthalimides, the phosphorescence remained unaltered for the solvent‐free liquid in air. As the first report, a solvent‐free liquid of a long swallow‐tailed bromonaphthalimide exhibits room‐temperature phosphorescence in air. Doping of the phosphor with carbonyl guests resulted in enhanced phosphorescence, and hence a large‐area paintable phosphorescent liquid composite with improved lifetime and quantum yield was developed.
The Comparability of Pt to Pt‐Ru in Catalyzing the Hydrogen Oxidation Reaction for Alkaline Polymer Electrolyte Fuel Cells Operated at 80 °C
Authors: Li Qihao , Peng Hanqing , Wang Yingming , Xiao Li , Lu Juntao , Zhuang Lin 
Published: December 2018

AbstractThe Pt‐catalyzed hydrogen oxidation reaction (HOR) for alkaline polymer electrolyte fuel cells (APEFCs) has been one of the focus subjects in current fuel‐cell research. The Pt catalyst is inferior for HOR in alkaline solutions, and alloying with Ru is an effective promotion strategy. APEFCs with Pt‐Ru anodes have provided a performance benchmark over 1 W cm−2 at 60 °C. The Pt anode is now found to be in fact as good as the Pt‐Ru anode for APEFCs operated at elevated conditions. At 80 °C with appropriate gas back‐pressure, the cell with a Pt anode exhibits a peak power density of about 1.9 W cm−2, which is very close to that with a Pt‐Ru anode. Even by decreasing the anode Pt loading to 0.1 mg cm−2, over 1.5 W cm−2 can still be achieved at 80 °C. This finding alters the previous understanding about the Pt catalyzed HOR in alkaline media and casts a new light on the development of practical and high‐power APFEC technology.
NiH‐Catalyzed Remote Asymmetric Hydroalkylation of Alkenes with Racemic α‐Bromo Amides
Authors: Zhou Fang , Zhang Yao , Xu Xianfeng , Zhu Shaolin 
Published: December 2018

AbstractReported here is a terminal‐selective, remote asymmetric hydroalkylation of olefins with racemic α‐bromo amides. The reaction proceeds by NiH‐catalyzed alkene isomerization and subsequent alkylation reaction, and can enantioconvergently introduce an unsymmetrical secondary alkyl group from a racemic α‐bromo amide onto a terminal C(sp3)−H position along the hydrocarbon chain of the alkene. This mild process affords a range of structurally diverse chiral α‐alkylalkanoic amides in excellent yields, and high regio‐ and enantioselectivities. In addition, the synthetic utility of this protocol is further highlighted by the regioconvergent conversion of industrial raw materials of isomeric olefin mixtures into enantioriched α‐alkylalkanoic amides on large scale.
Eine neue Strukturklasse neutraler borhaltiger Diradikale verbrückt über zwei Kohlenstoffatome
Authors: Deissenberger Andrea , Welz Eileen , Drescher Regina , Krummenacher Ivo , Dewhurst Rian D. , Engels Bernd , Braunschweig Holger 
Published: December 2018

AbstractEine neue Strukturklasse borhaltiger Diradikale wurde durch Lewis‐Basen‐Addition und Reduktion einfach CAAC‐stabilisierter Diborylalkene dargestellt. Die Diradikale besitzen eine senkrecht stehende olefinische Brücke, die eine Delokalisierung zwischen den B(CAAC)‐π‐Systemen verhindert, woraus eine lediglich sehr schwache Kopplung der Spinzentren resultiert. DFT‐Rechnungen deuten darauf hin, dass die Verbindungen einen offenschaligen Singulett‐Grundzustand besitzen, mit einem Triplettzustand, der energetisch vernachlässigbar höher liegt, weshalb eine leichte thermische Besetzung des letzteren möglich ist.
A New Class of Neutral Boron‐Based Diradicals Spanned by a Two‐Carbon‐Atom Bridge
Authors: Deissenberger Andrea , Welz Eileen , Drescher Regina , Krummenacher Ivo , Dewhurst Rian D. , Engels Bernd , Braunschweig Holger 
Published: December 2018

AbstractA new structural class of boron‐based diradicals is prepared by Lewis base addition to and reduction of singly cyclic (alkyl)(amino)carbene (CAAC) stabilised diborylalkenes. The diradicals feature a perpendicular olefinic bridge preventing delocalization between the B(CAAC) π systems, making the coupling between the spin centres very weak. DFT calculations indicate that the compounds are ground‐state (open‐shell) singlets, with triplet states negligibly higher in energy, thus making the triplet states easily populated thermally.
Preparation and properties of carbon‐fiber‐ and pine‐cone‐fiber‐reinforced high‐density polyethylene composites
Authors: Guo Yong , Liu Dian , Chen Yuxia , Zhang Tingting , Zhu Shiliu 
Published: December 2018

ABSTRACTIn this study, we were concerned with the physical properties of carbon‐fiber‐ and pine‐cone‐fiber‐reinforced high‐density polyethylene prepared by compression molding. The resulting composites were characterized by scanning electron microscopy, X‐ray diffraction, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and mechanical testing. The results indicate that the manufacturing properties of the composites were improved with the addition of carbon fibers. The FTIR results showed that the carbon‐fiber reinforcement of the composites was mainly achieved through physical effects. An appropriate content of carbon‐fiber addition improved the interface combination between the fibers and matrix; carbon fibers improve the water absorption of the material, and the relative crystallinity of the composite increased with increasing carbon‐fiber addition. With increasing carbon‐fiber content, the thermal decomposition temperature of the composites increased, and the thermal stability of the composites improved. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47304.
Calix[4]arene‐Based Bis(Nitric Oxide) Complexes: Synthesis, Physical Properties, and Structural Characterization
Authors: Wang Denan , Zhang Depeng , Lindeman Sergey V. , Rathore Rajendra 
Published: December 2018

AbstractCalix[4]arene‐based molecules hold great promise as candidate sensors and storage materials for nitric oxide (NO), owing to their unprecedented binding affinity for NO. However, the structure of calix[4]arene is complicated by the availability of four possible conformers: 1,3‐alternate, 1,2‐alternate, cone, and partial cone (paco). Whilst complexes of NO with several of these conformers have previously been established, the 1,2‐alternate conformer complex, that is, [1,2‐alter⋅NO]+, has not been previously reported. Herein, we determine the crystal structure of the NO complex with the 1,2‐alternate conformer for the first time. In addition, we have also found that the 1,2‐alternate and 1,3‐alternate conformers can combine with two NO molecules to form stable bis(nitric oxide) complexes. These new complexes, which exhibit remarkable binding capacity for the construction of NO‐storage molecules, were characterized by using X‐ray crystallography and NMR, IR, and UV/Vis spectroscopy. These findings will extend our understanding of the interactions between nitric oxide and cofacially and non‐cofacially arrayed aromatic rings, and we expect them to aid in the design and development of new supramolecular sensors and storage materials for NO with high capacity and efficacy.
Prevalence and descriptive epidemiology of infantile hypertrophic pyloric stenosis in the United States: A multistate, population‐based retrospective study, 1999–2010
Authors: Kapoor Renuka , Kancherla Vijaya , Cao Yanyan , Oleson Jacob , Suhl Jonathan , Canfield Mark A , Druschel Charlotte M , Kirby Russell S , Meyer Robert E , Romitti Paul A 
Published: December 2018

BackgroundAntecedents for infantile hypertrophic pyloric stenosis (IHPS) vary across studies; therefore, we conducted a multistate, population‐based retrospective study of the prevalence and descriptive epidemiology of IHPS in the United States (US).MethodsData for IHPS cases (n = 29,554) delivered from 1999–2010 and enumerated from 11 US population‐based birth defect surveillance programs, along with data for live births (n = 14,707,418) delivered within the same birth period and jurisdictions, were analyzed using Poisson regression to estimate IHPS prevalence per 10,000 live births. Additional data on deliveries from 1999–2005 from seven of these programs were analyzed using multivariable logistic regression to estimate adjusted prevalence ratios (aPR)s and 95% confidence intervals (CI)s for selected infant and parental characteristics.ResultsOverall, IHPS prevalence from 1999–2010 was 20.09 (95% CI = 19.87, 20.32) per 10,000 live births, with statistically significant increases from 2003–2006 and decreases from 2007–2010. Compared to their respective referents, aPRs were higher in magnitude for males, preterm births, and multiple births, but lower for birth weights <2,500 g. The aPRs for all cases increased with decreasing parental age, maternal education, and maternal parity, but decreased for parental race/ethnicity other than non‐Hispanic White. Estimates restricted to isolated cases or stratified by infant sex were similar to those for all cases.ConclusionsThis study covers one of the largest samples and longest temporal period examined for IHPS in the US. Similar to findings reported in Europe, estimates suggest that IHPS prevalence has decreased recently in the US. Additional analyses supported associations with several infant and parental characteristics.
Robotergestützte, magnetische Ausrichtung von Mikro‐Stahldrahtfasern in dünnwandigen UHPFRC‐Bauteilen
Authors: Ledderose Lukas , Lehmberg Sven , Budelmann Harald , Kloft Harald 
Published: December 2018

AbstractMithilfe der robotergestützten magnetischen Verteilung und Orientierung von Mikro‐Stahldrahtfasern in UHPFRC (Ultra‐High Performance Fiber‐Reinforced Concrete) soll der Einsatz von Stahlfasern als dezidiert notwendige Zugbewehrung ermöglicht werden. Ziel ist es, durch die magnetische Ausrichtung der Stahlfasern in der Frischbetonmatrix leistungsfähige Betonbauteile herzustellen. Die vorgestellte Forschung führt Möglichkeiten digitaler und robotergestützter Bauteilfertigung auf der einen Seite mit den Potenzialen der Faserausrichtung zur Steigerung der Materialeffizienz von UHPFRC auf der anderen Seite zusammen. Die gewählte Methode zur Verteilung und Orientierung der Mikro‐Stahldrahtfasern in UHPFRC basiert auf dem physikalischen Phänomen des Magnetismus. Da Mikro‐Stahldrahtfasern ferromagnetisch sind, kann deren Lage im frischen Beton durch Nutzung magnetischer Felder gezielt verändert werden. Die Magnetbehandlung zielt darauf ab, die Lage der Mikro‐Stahldrahtfasern in der Betonmatrix vor dem Erstarren entsprechend dem Kraftfluss in Richtung der Zugtrajektorien auszurichten. Erste Ergebnisse zeigen, dass die definierte Anordnung der Fasern in einem Bauteil die Effizienz des eingesetzten Faseranteils signifikant steigert und so neben einer verbesserten Verarbeitbarkeit des Frischbetons zu einer erheblichen Reduktion der eingesetzten Fasermenge führt, womit ein großes Einsparpotenzial an ökologischen und ökonomischen Ressourcen einhergeht.
Gene mutations in a Han Chinese Alzheimer's disease cohort
Authors: Ma Limin , Zhang Jiewen , Shi Yingying , Wang Wan , Ren Zhixia , Xia Mingrong , Zhang Yuanxing , Yang Miaomiao 
Published: December 2018

AbstractObjectiveAlzheimer's disease (AD) is the most common form of dementia characterized by memory loss at disease onset. The gene mutations in the amyloid precursor protein (APP), presenilin 1 (PSEN1), and presenilin 2 (PSEN2) are the frequent causes of AD. However, the clinical and genetic features of AD overlap with other neurodegenerative diseases. The present study aimed to identify the clinical and genetic characteristics in a Han Chinese AD cohort.MethodsDetailed clinical assessment was applied to all the patients. We screened amyloid precursor protein (APP), PSEN1, PSEN2, and microtubule‐associated protein tau (MAPT) genes were assessed in 83 sporadic AD patients by Sanger sequencing. A total of 25 probands from families with AD were subjected to next‐generation sequencing on 53 dementia‐associated genes to capture the target region, and Sanger sequencing was used to detect the variants in the DNA sequence.ResultsPSEN1 p.L226R was found in an early‐onset AD (EOAD) family characterized by language impairment at disease onset, a novel probably pathogenetic variant (p.D534H) was identified in a frontal‐temporal dementia gene, TANK‐binding kinase 1 (TBK1) with a typical AD phenotype in a late‐onset AD (LOAD) family, and a PSEN2p.H169N mutation and two benign MAPT (p.Q230R and p.V48L) mutations were detected in three EOAD patients.ConclusionsThus, five variants were identified in a Han Chinese cohort. In the present study, a novel, probably damaging FTLD gene TBK1variant with a typical AD phenotype was detected. Also, the phenotypic characteristics of PSEN1 p.L226R, a PSEN2pathogenic mutation, and two likely benign MAPT variants were described. Hence, screening for mutations in other dementia genes could be further explored in clinically diagnosed AD patients.
Electronic and Steric Control of n→π* Interactions: Stabilization of the α‐Helix Conformation without a Hydrogen Bond
Authors: Wenzell Nicole A. , Ganguly Himal K. , Pandey Anil K. , Bhatt Megh R. , Yap Glenn P. A. , Zondlo Neal J. 
Published: December 2018

AbstractThe preferred conformations of peptides and proteins are dependent on local interactions that bias the conformational ensemble. The n→π* interaction between consecutive carbonyls promotes compact conformations, including the α‐helix and polyproline II helix. In order to further understand the n→π* interaction and to develop methods to promote defined conformational preferences through acyl N‐capping motifs, a series of peptides was synthesized in which the electronic and steric properties of the acyl group were modified. Using NMR spectroscopy, van't Hoff analysis of enthalpies, X‐ray crystallography, and computational investigations, we observed that more electron‐rich donor carbonyls (pivaloyl, iso‐butyryl, propionyl) promote stronger n→π* interactions and more compact conformations than acetyl or less electron‐rich donor carbonyls (methoxyacetyl, fluoroacetyl, formyl). X‐ray crystallography indicates a strong, electronically tunable preference for the α‐helix conformation, as observed directly on the φ and ψ torsion angles. Electron‐donating acyl groups promote the α‐helical conformation, even in the absence of the hydrogen bonding that stabilizes the α‐helix. In contrast, electron‐withdrawing acyl groups led to more extended conformations. More sterically demanding groups can promote trans amide bonds independent of the electronic effect on n→π* interactions. Chloroacetyl groups additionally promote n→π* interactions through the interaction of the chlorine lone pair with the proximal carbonyl π*. These data provide additional support for an important role of n→π* interactions in the conformational ensemble of disordered or unfolded proteins. Moreover, this work suggests that readily incorporated acyl N‐capping motifs that modulate n→π* interactions may be employed rationally to promote conformational biases in peptides, with potential applications in molecular design and medicinal chemistry.
Optimal medical therapy vs. coronary revascularization for patients presenting with chronic total occlusion: A meta‐analysis of randomized controlled trials and propensity score adjusted studies
Authors: Iannaccone Mario , D'ascenzo Fabrizio , Piazza Fabio , De Benedictis Michele , Doronzo Baldassarre , Behnes Michael , Garbo Roberto , Mashayekhi Kambis 
Published: December 2018

AbstractIntroductionThe optimal management of patients with coronary chronic total occlusions (CTO) remains controversial. This meta‐analysis aims to compare percutaneous coronary intervention of CTO (CTO‐PCI) versus optimal medical therapy (OMT) in CTO patients.MethodsA literature search with highly specific terms was conducted using MEDLINE, EMBASE, and Web of Science to identify most relevant randomized controlled trials (RCTs) and observational studies with propensity score matching (PSM) evaluating differences in between CTO‐PCI versus OMT. The primary endpoint was the incidence of major adverse cardiac events (MACEs, composite of cardiovascular death, acute coronary syndrome, and repeat PCI, re‐PCI) while its single components were defined as secondary endpoints.ResultsA total of eight studies was included, four RCTs and four PSMs. 3,971 patients were included in the analysis (2,050 CTO‐PCI versus 1,921 OMT) with a mean follow‐up of 3 years. No significant differences were found regarding overall MACE, re‐PCI and AMI. Regarding CV‐death, CTO‐PCI was associated with a better outcome compared with OMT driven by PSMs (OR 0.52, 0.0.81, P < 0.01).ConclusionsAs compared to OMT, CTO‐PCI was associated with similar MACE rate; however, CTO‐PCI may be associated with reduced CV death, mainly due to PSMs effect.
Use of Boron‐Doped Diamond Electrodes in Electro‐Organic Synthesis
Authors: Lips Sebastian , Waldvogel Siegfried R. 
Published: December 2018

AbstractBoron‐doped diamond is a powerful and innovative material with outstanding properties, experiencing a strongly emerging interest in the chemical society as electrode material. BDD is generally used as a p‐doped semiconductor that can be applied for the disinfection and detoxification of waste‐water since very reactive intermediates can be formed. Besides this destructive performance of BDD electrodes the extraordinary characteristics can also be successfully employed in electro‐synthetic transformations. The performance is usually beyond and much superior to common electrode materials. A key step for the broad interdisciplinary field of application of this particular electrode material is the direct generation of oxyl radicals by electrochemical oxidation. The intention of this mini‐review is to provide the reader a brief overview of the current state of research and to illustrate the different fields of application. The methods applied are critically reviewed.
Isothiourea‐Catalysed Regioselective Acylative Kinetic Resolution of Axially Chiral Biaryl Diols
Authors: Qu Shen , Greenhalgh Mark D. , Smith Andrew D. 
Published: December 2018

AbstractAn operationally simple isothiourea‐catalysed acylative kinetic resolution of unprotected 1,1′‐biaryl‐2,2′‐diol derivatives has been developed to allow access to axially chiral compounds in highly enantioenriched form (s values up to 190). Investigation of the reaction scope and limitations provided three key observations: i) the diol motif of the substrate was essential for good conversion and high s values; ii) the use of an α,α‐disubstituted mixed anhydride (2,2‐diphenylacetic pivalic anhydride) was critical to minimize diacylation and give high selectivity; iii) the presence of substituents in the 3,3′‐positions of the diol hindered effective acylation. This final observation was exploited for the highly regioselective acylative kinetic resolution of unsymmetrical biaryl diol substrates bearing a single 3‐substituent. Based on the key observations identified, acylation transition state models have been proposed to explain the atropselectivity of this kinetic resolution.
Synthesis of Fluorescent Au Clusters Using Self‐Assembled Tripeptides as Reducing Soft Templates
Authors: Lv Peng , Qiu Lihong , Zhao Cuilian , Fang Guozhen , Liu Jifeng , Wang Shuo 
Published: December 2018

AbstractIn this work, self‐assembling tripeptides as reducing soft templates to synthesize gold nanoclusters (AuNCs) is reported for the first time. Three tripeptides (i. e., CFF, FCC, and PCF) are self‐assembled to form soft templates with different morphologies (nanofibers, nanorings and nanoparticles, respectively) by cryogenic treatment under a mixed solvent condition (tetrahydrofuran/water=8/1). All‐atom molecular dynamics (MD) simulation is used to investigate the self‐assembling process of the tripeptides. Polydispersed AuNCs with different Au core can be obtained in presence of the soft templates and the size of AuNCs shows a dependence on the soft templates. The size of AuNCs are determined by the distribution of the −SH sites on the assembled peptides skeletons and steric hindrance of soft templates. A physical model and an equation are proposed to describe the factors determining the size of aggregate AuNCs on soft templates. Finally, fluorescent AuNCs on FCC soft template were applied to bioimaging.
β‐Cyclodextrin‐Decorated Carbon Dots Serve as Nanocarriers for Targeted Drug Delivery and Controlled Release
Authors: Yang Ting , Huang Jing‐Li , Wang Yi‐Ting , Zheng An‐Qi , Shu Yang , Wang Jian‐Hua 
Published: December 2018

AbstractA novel nanocarrier for targeted delivery of anti‐cancer drug doxorubicin (DOX) was fabricated with carbon dots (CDots) as the matrix. Fluorescent CDots capable of targeting folate receptor‐positive cells first conjugate with boric acid and then couple with β‐CD to produce the nanocarrier β‐CD/CDots. DOX was encapsulated into the cavity of β‐CD providing a maximum loading ratio of 27.3% at pH 7.4. Benefiting from pH‐sensitive dissociation of DOX/β‐CD inclusion complex and the cleavage of the bonding between boric acid and β‐CD, pH‐triggered release of drugs was realized, with an 82% release of the loaded drug at pH 5.0. Meanwhile, the fluorescence resonance energy transfer (FRET) occurs between CDots (donor) and DOX (acceptor), which may potentially facilitate monitoring/tracing of the drug delivery process. In vitro results further demonstrated the targeting capability of the nanocarrier towards folate receptor‐positive cells. Moreover, confocal microscopy results, in accordance with that of flow cytometry analysis, confirmed the efficient intracellular uptake of DOX‐β‐CD/CDots and sustained release of DOX. This makes DOX‐β‐CD/CDots promising as biocompatible and multifunctional nanomedicine for targeted delivery, controlled release and real time monitoring/tracing of drugs.
Design and evaluation of a parallel document clustering algorithm based on hierarchical latent semantic analysis
Authors: Seshadri Karthick , Iyer K. Viswanathan , S Mercy Shalinie 
Published: December 2018

SummaryWe propose a parallel generalization scheme for Singular Value Decomposition–based clustering algorithms. The scheme enables the clustering algorithm to generate a hierarchy of clusters instead of a flat set of clusters. The generalization scheme infers the number of levels to be formed and the number of clusters per level of the hierarchy automatically without depending on any user‐supplied parameter. The performance of the suggested hierarchical clustering algorithm was evaluated using the web directory taxonomy hosted by the Open Directory DMOZ. Empirical evaluations and statistical tests reveal that the proposed generalization scheme produces a superior cluster hierarchy when compared with two existing generalization techniques in terms of the precision, recall, f‐measure, and the rand index. The generalization scheme is well‐equipped to deal with large datasets and the speed‐up achieved by the parallelized generalization scheme over its sequential variant was measured using a multicore computer.