bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facile synthesis of ethylene–propylene fully alternating copolymer and comparison with random copolymer of similar composition
Authors: Song Shao‐Fei , Fu Zhi‐Sheng , Xu Jun‐Ting , Fan Zhi‐Qiang 
Published: October 2017

ABSTRACTA precisely sequenced ethylene–propylene (EP) fully alternating copolymer was synthesized via trans‐1,4‐polymerization of isoprene catalyzed by Ziegler–Natta catalyst followed by hydrogenation. This EP copolymer was used as model polymer for studying structure–property relationship. An ethylene–propylene random copolymer (ethylene–propylene rubber [EPR]) with similar ethylene content was also prepared for comparison, and the effect of comonomer sequence distribution on properties was investigated. The copolymer chain structures were monitored by 1H and 13C NMR and Fourier translation infrared. Differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, and tensile tests were employed to determine the thermal and mechanical properties. The fully alternating copolymer EP gives a more precise glass transition comparing than EPR. Further understanding on thermal properties and aggregation behavior of ethylene–propylene copolymers is made possible by this comparative study. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45816.
Experimental and simulated investigation of temperature distribution of UHMWPE laminated composites during hot pressing process
Authors: Zeng Zheng , Guo Bingbing , Li Min , Li Jing , Zhou Xiao Dong 
Published: October 2017

ABSTRACTIn this article, the influence of molding temperature on the mechanical properties and ballistic impact behavior of the ultrahigh molecular weight polyethylene (UHMWPE) laminated composites has been investigated. The results demonstrate that with the temperature increasing from 80 to 120 °C, the tensile strength decreases while the interlaminar bonding strength increases. The UHMWPE laminated composites manufactured by hot pressing of 75 layers UHMWPE fabrics show excellent ballistic performance when the molding temperature reaches 120 °C, indicating that dominant failure mechanism of the UHMWPE laminated composites are delamination, the fiber tension as well as bulging. Furthermore, a numerical model has been proposed to predict the temperature distribution of the UHMWPE laminated composites for a better understanding of the effect of molding temperature on the ballistic performance. The results show that the simulated results and experimental data are in good agreement. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45874.
Conjugated Microporous Polymers for Heterogeneous Catalysis
Authors: Zhou Yun‐Bing , Zhan Zhuang‐Ping 
Published: October 2017

AbstractConjugated microporous polymers (CMPs) are a class of crosslinked polymers that combine permanent micropores with π‐conjugated skeletons and possess three‐dimensional (3D) networks. Compared with conventional materials such as metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), CMPs usually have superior chemical and thermal stability. CMPs have made significant progress in heterogeneous catalysis in the past seven years. With a bottom‐up strategy, catalytic moieties can be directly introduced into in the framework to produce heterogeneous CMP catalysts. Higher activity, stability, and selectivity can be obtained with heterogeneous CMP catalysts in comparison with their homogeneous analogs. In addition, CMP catalysts can be easily isolated and recycled. In this review, we focus on CMPs as an intriguing platform for developing various highly efficient and recyclable heterogeneous catalysts in organic reactions. The design, synthesis, and structure of these CMP catalysts are also discussed in this focus review.
Prognostic value of the cancer oncogene Kelch-like 6 in gastric cancer
Authors: Deng J , Guo J , Ma G , Zhang H , Sun D , Hou Y , Xie X , Guo X , Nie Y , Liang H 
Published: October 2017

Abstract

Background
Kelch-like 6 (KLHL6) is a cancer oncogene previously associated with specific human cancers, such as chronic lymphocytic leukaemia. Here, the mechanisms of KLHL6 function were explored in gastric cancer (GC) cells, in an in vivo experimental tumour model, and the prognostic value of KLHL6 analysis in GC tissue evaluated in a cohort of patients with GC.

Methods
Associations between clinicopathological and survival data and KLHL6 expression in GC tissues were analysed. The effects of downregulation of KLHL6 in GC cells was investigated using proliferation, invasion, apoptosis and lymphangiogenesis assays, and analysis of tumour growth in an in vivo experimental model.

Results
KLHL6 was upregulated in 43 per cent of GC tissues compared with 5 per cent of paired non-tumour tissues from 84 patients. KLHL6 protein expression in GC tissues was much higher than that in atrophic gastritis, intestinal metaplasia and dysplasia tissues from benign gastric disease samples. KLHL6 expression was positively related to the intestinal Laurén classification in GC tissues. Downregulated expression of KLHL6 in MGC-803 GC cells reduced colony formation, proliferation, viability, migration and invasion, enhanced apoptosis and inhibited the cell cycle in the G1 phase. Downregulated expression of KLHL6 also suppressed tumour growth in mice. Furthermore, downregulated expression of KLHL6 mRNA reduced the expression of nuclear-associated antigen Ki-67, vascular endothelial growth factor C, hepatocyte growth factor and matrix metalloproteinase 2 in vitro, and KLHL6 protein in tumour tissue of mice.

Conclusion
Abnormal expression of the KLHL6 oncogene promoted GC progression in vitro and in vivo, and its expression level in tumour tissue was found to be of prognostic value.
Meta-analysis of the association between peripheral artery disease and growth of abdominal aortic aneurysms
Authors: Matthews E O , Rowbotham S E , Moxon J V , Jones R E , Vega de Ceniga M , Golledge J 
Published: October 2017

Abstract

Background
The role of atherosclerosis in the pathogenesis of abdominal aortic aneurysm (AAA) is controversial. Atherosclerosis-associated peripheral artery disease (PAD) has been reported to be a risk factor for AAA in population screening studies; its relationship with AAA growth is controversial.

Methods
A systematic search of MEDLINE, Scopus, CINAHL and the Cochrane Central Register of Controlled Trials was conducted in April 2016 and repeated in January 2017. Databases were screened for studies reporting AAA growth rates in patients with, and without PAD. The included studies underwent quality assessment and, where possible, were included in the meta-analysis. A subgroup analysis was performed, including only studies that adjusted for confounding factors.

Results
Seventeen studies, including a total of 4873 patients, met the review entry criteria. Data from 15 studies were included in the meta-analysis. There was marked heterogeneity in study design, methodology and statistical analyses used. In the main analysis, PAD was associated with reduced AAA growth (mean difference – 0·13, 95 per cent c.i. –0·27 to –0·00; P = 0·04). However, statistical significance was not maintained in sensitivity analysis. In a subanalysis that included only data adjusted for other risk factors, no significant association between PAD and AAA growth was found (mean difference –0·11, –0·23 to 0·00; P = 0·05).

Conclusion
This systematic review suggests that currently reported studies demonstrate no robust and consistent association between PAD and reduced AAA growth.
Zinc–Azatrane Complexes as Efficient Catalysts for the Conversion of Carbon Dioxide into Cyclic Carbonates
Authors: Bousquet Benjamin , Martinez Alexandre , Dufaud Véronique 
Published: October 2017

AbstractThree Zn complexes based on the N4‐tris(2‐aminoethyl)amine (tren) chelating ligand and presenting a C3‐symmetrical axis were synthesized and successfully applied in the coupling of CO2 with terminal and internal epoxides. These complexes proved to be efficient catalysts if associated with tetrabutylammonium iodide, even at a low catalyst loading (0.005 mol %) or at room temperature, and allowed the production of cyclic carbonates in good to high yields. Variation of the substitution pattern on the tren ligand was shown to impact the catalyst performance greatly, and the highest turnover number (TON) (up to 11 200) was achieved with the less sterically hindered methyl‐substituted ZnII–azatrane complex. These binary Zn–azatrane/NBu4I catalytic systems could be applied to a wide range of epoxide substrates, including the more challenging internal epoxides. Moreover, although soluble in the reaction medium, Zn–azatrane catalysts could be easily recovered and reused up to three times without any substantial loss in activity, proving their robustness under the reaction conditions.
Zeolite‐Y‐Mediated Multicomponent Reaction of Isatins, Cyclic 1,3‐Diketones, and 1,2‐Phenylenediamine: Easy Access to Spirodibenzo[1,4]diazepines
Authors: De Kajal , Bhanja Piyali , Bhaumik Asim , Mukhopadhyay Chhanda 
Published: October 2017

AbstractA facile and efficient one‐pot, three‐component approach for the synthesis of spirodibenzo[1,4]diazepine derivatives has been achieved by the reaction of isatins, cyclic 1,3‐diketones, and 1,2‐phenylenediamines in the presence of a Zeolite‐Y nanopowder catalyst. The Zeolite‐Y nanopowder catalyst was synthesized and characterized thoroughly by using XRD, high‐resolution transmission electron microscopy, energy‐dispersive spectroscopy, and N2‐adsorption analysis. We used X‐ray photoelectron spectroscopy to investigate the electronic environment and oxidation state of the elements.
Cobalt−Iron Pyrophosphate Porous Nanosheets as Highly Active Electrocatalysts for the Oxygen Evolution Reaction
Authors: Liu Miaomiao , Qu Zhengyi , Yin Deqin , Chen Xiaojuan , Zhang Yajie , Guo Yong , Xiao Dan 
Published: October 2017

AbstractOne of the challenges to realize large‐scale water splitting is the sluggish kinetics of the anode reaction. Nowadays, metal phosphates are widely used as high‐efficiency catalysts for the oxygen evolution reaction (OER). In this work, we studied common phosphoric acid salts including orthophosphate, pyrophosphate, and tripolyphosphate in a bimetallic catalyst to explore the effect of the anion in phosphate‐based OER electrocatalysts. Co−Fe‐Pi, Co−Fe‐Pyro, and Co−Fe‐Pyro were successfully synthesized through a simple and convenient co‐precipitation method. Among them, Co−Fe‐Pyro exhibits the best electrocatalytic activity, with a low overpotential of 276 mV at a current density of 10 mA cm−2, a small Tafel slope of 32 mV dec−1, and a durable stability of about 90 % after 30000 s at 1.62 V vs. RHE in 1 M KOH. XRD reveals the amorphous structure of the materials and XPS confirms the formation of Co−Fe‐Pyro. SEM and TEM present the nanosheets with a porous structure on the surface of Co−Fe‐Pyro. The distribution and ratio of the elements in Co−Fe‐Pyro are confirmed by using EDS and ICP‐AES. Therefore, this work promotes a new thought regarding the anion structure in the phosphate‐based electrocatalysts.
Continuous Flow Synthesis of Platinum Nanoparticles in Porous Carbon as Durable and Methanol‐Tolerant Electrocatalysts for the Oxygen Reduction Reaction
Authors: Domínguez Carlota , Metz Kevin M. , Hoque Md. Khairul , Browne Michelle P. , Esteban‐Tejeda Leticia , Livingston Corbin K. , Lian Suoyuan , Perova Tatiana S. , Colavita Paula E. 
Published: October 2017

AbstractThe development and commercialization of direct methanol fuel cells (DMFCs) as energy conversion devices remains a challenge despite their advantages in terms of energy density and energy‐conversion efficiency. The bottleneck for the development of DMFCs is mainly caused by the sluggish kinetics of the oxygen reduction reaction (ORR) at the cathode of fuel cells, and the effect of the so‐called methanol crossover in state‐of‐the‐art Pt/C electrocatalysts. Herein, we report for the first time an easily scalable continuous flow method based on ultraspray pyrolysis (USP) for the preparation of Pt nanoparticles directly embedded on highly porous carbon spheres. A study on the effect that post‐synthesis treatment procedures have on the level of graphitization and catalytic properties is described. Use of USP results in a substantial reduction of the final Pt content with respect to typical Pt/C electrocatalysts, while yielding also excellent durability and tolerance to methanol crossover under acidic conditions. These results demonstrate that the USP method reported herein is a good candidate for its use in the preparation of ORR catalysts in commercial applications.
Nonlinear classification of commercial Mexican tequilas
Authors: Andrade Jose Manuel , Ballabio Davide , Gómez‐Carracedo Maria Paz , Pérez‐Caballero Guadalupe 
Published: October 2017

AbstractDiscriminant partial least squares (PLS‐DA)—a de facto standard classification method—was found to behave poorly when 3 classes of tequilas were modeled to study a collection of 170 commercial Mexican spirits measured by UV‐Vis spectroscopy. This result was compared with other linear and nonlinear supervised classification methods (PLS with variable selection by SRI index and genetic algorithms; kernel‐PLS—modified in this paper to handle simultaneously several classes, quadratic discriminant analysis (QDA), support vectors machines, and counter‐propagation artificial neural networks). All linear models performed worse than nonlinear ones, and this was attributed to the quite different inner dispersion of the classes and the intermediate position of 1 class. Considering the overall classification results and parsimony, QDA was selected for routine assessments thanks to its simplicity and broad availability.
Ensemble calibration for the spectral quantitative analysis of complex samples
Authors: Bian Xihui , Diwu Pengyao , Liu Yirui , Liu Peng , Li Qian , Tan Xiaoyao 
Published: October 2017

AbstractEnsemble strategies have gained increasing attention in multivariate calibration for quantitative analysis of complex samples. The aim of ensemble calibration is to obtain a more accurate, stable, and robust prediction by combining the predictions of multiple submodels. The generation and calibration of the training subsets, as well as the integration of the submodels, are three keys to the success of ensemble calibration. Many training subset generating and submodel integrating strategies have been developed to form numerous ensemble calibration methods for improving the performance of the basic calibration method. This contribution focuses on the recent ensemble strategies in relation to calibration, especially the ensemble modeling for quantitative analysis of complex samples. The limitations and perspectives of ensemble strategies are also discussed.
Breaking the Concentration Barrier for Single‐Molecule Fluorescence Measurements
Authors: Peng Sijia , Wang Wenjuan , Chen Chunlai 
Published: October 2017

AbstractFluorescence‐based single‐molecule techniques have become widely used tools to reveal dynamic processes of biomolecules and elucidate their molecular mechanisms. However, the concentration upper limit of labeled species that can be used in single‐molecule fluorescence measurements is at the low nm range, which is below the Michaelis constants of many enzymatic reactions and physiological concentrations of many biomolecules. Such discrepancy limits the application of single‐molecule fluorescence tools. Several techniques have been developed to break the concentration barrier. In this Concept, we focus on reviewing fundamental principles of these techniques and wish to inspire development of new and better tools to achieve this goal.
A Novel Approach to Synthesise a Dual‐Mode Luminescent Composite Pigment for Uncloneable High‐Security Codes to Combat Counterfeiting
Authors: Kanika  , Kumar Pawan , Singh Satbir , Gupta Bipin Kumar 
Published: October 2017

AbstractA strategy is demonstrated to protect valuable items, such as currency, pharmaceuticals, important documents, etc. against counterfeiting, by marking them with luminescent security codes. These luminescent security codes were printed by employing luminescent ink formulated from a cost effective dual‐mode luminescent composite pigment of Gd1.7Yb0.2Er0.1O3 and Zn0.98Mn0.02S phosphors using commercially available PVC Gold medium. In the composite, Gd1.7Yb0.2Er0.1O3 and Zn0.98Mn0.02S account for upconversion and downconversion processes, respectively. The synthesis procedure of the composite involves the admixing of Gd1.7Yb0.2Er0.1O3 nanorods and Zn0.98Mn0.02S phosphor, synthesised by hydrothermal and facile solid‐state reaction methods, respectively. The structural, morphological, microstructural, and photoluminescent features of Gd1.7Yb0.2Er0.1O3 nanorods, Zn0.98Mn0.02S phosphor and composite were characterised by using XRD, SEM, TEM, and photoluminescence (PL) techniques, respectively. The distribution of PL intensity of the printed pattern was examined by using confocal PL mapping microscopy. The obtained results reveal that security codes printed using ink formulated from this bi‐luminescent composite pigment provide dual‐stage security against counterfeiting.
Desymmetrization of Bisallylic Amides through Catalytic Enantioselective Bromocyclization with BINAP Monoxide
Authors: Nagao Yoshihiro , Hisanaga Tatsunari , Egami Hiromichi , Kawato Yuji , Hamashima Yoshitaka 
Published: October 2017

AbstractWe report the first desymmetrization of bisallylic amides by enantioselective bromocyclization with BINAP monoxide as a catalyst. Depending upon the substitution pattern of the alkene moieties, densely functionalized, optically active oxazoline or dihydrooxazine compounds were obtained in a highly stereoselective manner. The remaining alkene moiety was subjected to various functional group manipulations to afford a diverse array of chiral molecules with multiple stereogenic centers.
C2‐Modified Sparteine Derivatives Are a New Class of Potentially Long‐Acting Sodium Channel Blockers
Authors: Gawali Vaibhavkumar S. , Simeonov Svilen , Drescher Martina , Knott Thomas , Scheel Olaf , Kudolo John , Kählig Hanspeter , Hochenegg Ulla , Roller Alexander , Todt Hannes , Maulide Nuno 
Published: October 2017

AbstractThe lupin alkaloid sparteine is a well‐known chiral diamine with a range of applications in asymmetric synthesis, as well as a blocker of voltage‐gated sodium channels (VGSCs). However, there is only scarce information on the VGSC‐blocking activity of sparteine derivatives where the structure of the parent alkaloid is retained. Building on the recent renewed availability of sparteine and derivatives we report herein how modification of sparteine at position 2 produces irreversible blockers of VGSCs. These compounds could be clinically envisaged as long‐lasting local anesthetics.
Patient‐reported quality‐of‐life outcomes after de‐escalated chemoradiation for human papillomavirus‐positive oropharyngeal carcinoma: Findings from a phase 2 trial
Authors: Hegde John V. , Shaverdian Narek , Daly Megan E. , Felix Carol , Wong Deborah L. , Rosove Michael H. , Garst Jordan H. , Wang Pin‐Chieh , Veruttipong Darlene , Rao Shyam , Fragoso Ruben C. , Riess Jonathan W. , Steinberg Michael L. , Chen Allen M. 
Published: October 2017

BACKGROUNDThe current study represents a subset analysis of quality‐of‐life (QOL) outcomes among patients treated on a phase 2 trial of de‐escalated chemoradiation for human papillomavirus (HPV)‐associated oropharyngeal cancer.METHODSEligibility included newly diagnosed, (American Joint Committee on Cancer, 7th edition) stage III or IV oropharyngeal squamous cell carcinoma, p16 positivity, age ≥ 18 years, and a Zubrod performance status of 0 to 1. Treatment was induction paclitaxel at a dose of 175 mg/m2 and carboplatin at an area under the curve of 6 for 2 cycles followed by response‐adapted, dose‐reduced radiation of 54 Gy or 60 Gy with weekly concurrent paclitaxel at a dose of 30 mg/m2. The University of Washington Quality of Life (UW‐QOL) and the Functional Assessment of Cancer Therapy‐Head and Neck questionnaires were used to assess patient‐reported QOL as a secondary endpoint.RESULTSA total of 45 patients were registered, 40 of whom completed QOL surveys and were evaluable. Nadirs for overall UW‐QOL and Functional Assessment of Cancer Therapy‐Head and Neck scores were reached at 4 weeks after treatment but returned to baseline at 3 months. Nearly all functional indices returned to baseline levels by 6 to 9 months. The mean overall UW‐QOL score was 71.6 at baseline compared with 70.8, 73.0, 83.3, and 81.1, respectively, at 3 months, 6 months, 1 year, and 2 years after therapy. The percentage of patients rating their overall QOL as “very good” or “outstanding” at 6 months, 1 year, and 2 years using the UW‐QOL was 50%, 77%, and 84%, respectively.CONCLUSIONSThis de‐escalation regimen achieved QOL outcomes that were favorable compared with historical controls. These results serve as powerful evidence that ongoing de‐escalation efforts lead to tangible gains in function and QOL. Cancer 2018;124:521‐9. © 2017 American Cancer Society.
BRCA mutations in women with inflammatory breast cancer
Authors: Gutierrez Barrera Angelica M. , Fouad Tamer M. , Song Juhee , Webster Rachel , Elsayegh Nisreen , Wood Anita L. , Demir Atakan , Litton Jennifer K. , Ueno Naoto T. , Arun Banu K. 
Published: October 2017

BACKGROUNDInflammatory breast cancer (IBC) often affects women at a relatively young age. To the authors' knowledge, the rate of BRCA variants among patients with IBC is not known. To determine the association between BRCA status and IBC, the authors evaluated its rate and compared the clinicopathologic characteristics of patients with IBC with those of patients with other breast cancers (non‐IBC).METHODSPatients who presented at the study institution's cancer genetics program and who underwent BRCA genetic testing were included in the current study. The authors compared clinicopathologic data between patients with IBC and those with non‐IBC using propensity score matching to identify predictors.RESULTSA total of 1789 patients who underwent BRCA genetic testing (1684 with non‐IBC and 105 with IBC) were included. BRCA pathogenic variants were found in 27.3% of patients with non‐IBC and 18.1% of patients with IBC (P = .0384). After propensity score matching, there were no significant differences noted between patients with IBC and those with non‐IBC, including the rate of BRCA pathogenic variants (P = .5485). However, a subgroup analysis of the 479 patients with BRCA pathogenic variants demonstrated that patients with IBC (19 patients) were diagnosed at significantly younger ages compared with patients with non‐IBC (P = .0244).CONCLUSIONSThere was no clear association observed between BRCA pathogenic variants and IBC. However, among patients who tested positive for BRCA pathogenic variants, those with IBC were younger at the time of diagnosis compared with those with non‐IBC breast cancers. These results confirm that genetic testing is important for patients with IBC who meet the current clinical criteria for genetic testing in breast cancer. Cancer 2018;124:466‐74. © 2017 American Cancer Society.