bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nickel‐Catalyzed Reductive Cross‐Coupling of Aryl Halides with Monofluoroalkyl Halides for Late‐Stage Monofluoroalkylation
Authors: Sheng Jie , Ni Hui‐Qi , Zhang Hao‐Ran , Zhang Kai‐Fan , Wang Yi‐Ning , Wang Xi‐Sheng 
Published: April 2018

AbstractA combinatorial nickel‐catalyzed monofluoroalkylation of aryl halides with unactivated fluoroalkyl halides by reductive cross‐coupling has been developed. This method demonstrated high efficiency, mild conditions, and excellent functional‐group tolerance, thus enabling the late‐stage monofluoroalkylation of diverse drugs. The key to success was the combination of diverse readily available bidentate and monodentate pyridine‐type nitrogen ligands with nickel, which in situ generated a variety of readily tunable catalysts to promote fluoroalkylation with broad scope with respect to both coupling partners. This combinatorial catalysis strategy offers a solution for nickel‐catalyzed reductive cross‐coupling reactions and provides an efficient way to synthesize fluoroalkylated druglike molecules for drug discovery.
Supramolecular Copolymerization by Sequence Reorganization of a Supramolecular Homopolymer
Authors: Nadamoto Kouhei , Maruyama Kei , Fujii Naoka , Ikeda Toshiaki , Kihara Shin‐ichi , Haino Takeharu 
Published: April 2018

AbstractThe homopolymeric sequence formed by the head‐to‐head association of tetrakisporphyrin 1 is completely dissociated by the competitive association of the ditopic guest G2, resulting in the supramolecular copolymer poly‐1⋅G2 with an alternatingly repeating host–guest sequence. The 1:1 stoichiometry of 1 and G2 is confirmed by a Job plot using UV/Vis titration and diffusion‐ordered NMR spectroscopy (DOSY). The solution viscometry for poly‐1 and poly‐1⋅G2 suggests that the supramolecular chain of poly‐1 behaves like a rod, whereas the supramolecular copolymer chain of poly‐1⋅G2 behaves like a swelled fat chain, which is entangled in the semi‐dilute regime. Atomic force microscopy shows that the supramolecular polymer poly‐1⋅G2 is highly oriented through the interdigitation of the long alkyl chains.
Robust SnO2−x Nanoparticle‐Impregnated Carbon Nanofibers with Outstanding Electrochemical Performance for Advanced Sodium‐Ion Batteries
Authors: Ma Dingtao , Li Yongliang , Mi Hongwei , Luo Shan , Zhang Peixin , Lin Zhiqun , Li Jianqing , Zhang Han 
Published: April 2018

AbstractThe sluggish sodium reaction kinetics, unstable Sn/Na2O interface, and large volume expansion are major obstacles that impede practical applications of SnO2‐based electrodes for sodium‐ion batteries (SIBs). Herein, we report the crafting of homogeneously confined oxygen‐vacancy‐containing SnO2−x nanoparticles with well‐defined void space in porous carbon nanofibers (denoted SnO2−x/C composites) that address the issues noted above for advanced SIBs. Notably, SnO2−x/C composites can be readily exploited as the working electrode, without need for binders and conductive additives. In contrast to past work, SnO2−x/C composites‐based SIBs show remarkable electrochemical performance, offering high reversible capacity, ultralong cyclic stability, and excellent rate capability. A discharge capacity of 565 mAh g−1 at 1 A g−1 is retained after 2000 cycles.
Beryllium Complexes with Bio‐Relevant Functional Groups: Coordination Geometries and Binding Affinities
Authors: Müller Matthias , Buchner Magnus R. 
Published: April 2018

AbstractThe coordination mode around beryllium in proteins and the binding affinity towards the peptide are unknown because there have been no coordination compounds of beryllium with ligands bearing bio‐relevant functional groups. We report the first comprehensive study on Be complexes with monodentate carboxylic acids, esters, aldehydes, and alcohols. Through solution and solid‐state techniques we determined that the binding affinities of Be2+ ions towards the functional groups are: carboxylate > alcohol > aldehyde > ester. Crystal structures of all the compounds have been determined including the unprecedented dodeca‐nuclear macrocyclic ring structure of non‐basic beryllium benzoate, which is the first example of those beryllium carboxylates. These findings enable the evaluation of potential beryllium binding sites inside proteins and is required to understand the mechanism of metal‐triggered immune responses.
LiAlH4: From Stoichiometric Reduction to Imine Hydrogenation Catalysis
Authors: Elsen Holger , Färber Christian , Ballmann Gerd , Harder Sjoerd 
Published: April 2018

AbstractImine‐to‐amine conversion with catalytic instead of stoichiometric quantities of LiAlH4 is demonstrated (85 °C, catalyst loading≥2.5 mol %, pressure≥1 bar). The effects of temperature, pressure, solvent, and catalyst modifications, as well as the substrate scope are discussed. Experimental investigations and preliminary DFT calculations suggest that the catalytically active species is generated in situ: LiAlH4+Ph(H)C=NtBu→LiAlH2[N(tBu)CH2Ph]2. A cooperative mechanism in which Li and Al both play a prominent role is proposed.
Poly(decamethylene terephthalamide) copolymerized with long‐chain alkyl dodecanedioic acid: Toward bio‐based polymer and improved performances
Authors: Zou Guangji , Wang Pingli , Feng Wutong , Ren Zhonglai , Ji Junhui 
Published: April 2018

ABSTRACTPoly(decamethylene terephthalamide) (PA10T), a bio‐based high‐performance semi‐aromatic polyamide, has been commercialized in recent years. However, there still are some weaknesses restricting its application range, such as narrow melt processing window and low ductility. In this study, we chose dodecanedioic acid (a potential bio‐based raw material) as the comonomer to prepare copolyamides [poly(decamethylene terephthalamide/decamethylene dodecanediamide), PA10T/1012] for solving these problems. The basic properties of these copolyamides were characterized by viscosity measurement, Fourier transform infrared spectrometer, proton nuclear magnetic resonance, wide‐angle X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, and tensile measurement. Results show that, compared to PA10T, PA10T/1012 exhibits wider melt processing window and more outstanding elongation at break. Meanwhile, PA10T/1012 is still qualified for high temperature resistant material. Furthermore, Tg, Td,5%, Td,10%, and Td,max of PA10T/1012 show a linear dependence on 1012 content, which is helpful to design new bio‐based copolyamides for meeting the needs of various occasions. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46531.
Improved specific capacity of sulfur/starch‐based activated carbon spheres composites by polyaniline‐based carbon encapsulation strategy
Authors: Zhao Shuo , Guo Qun , Xian Xiaochao , Wang Jin 
Published: April 2018

ABSTRACTLithium‐sulfur battery is one of the most promising electrochemical energy storage systems because of its high theoretical specific capacity and energy density. When carbon materials are used for immobilizing sulfur, the technical challenge is designing their framework to relieve the shuttle effect of polysulfides intermediates and the volume change of sulfur, and to improve the conductivity of sulfur. Herein, polyaniline‐based carbon (PANI‐C) coated corn starch‐based activated carbon spheres (ACS@PANI‐C) was prepared and used as hosts of sulfur, which can effectively combine the advantages of physical entrapment and chemical binding interactions of sulfur species. The results of electrochemical performance test indicate that S/ACS@PANI‐C composites exhibit much better electrochemical performance than S/ACS composites. Its reversible capacities at 320, 480, 800 and 1600 mA g−1 are 687, 582, 504 and 393 mAh g−1, respectively. The improved electrochemical performance can be attributed to the PANI‐C which can also act as a flexible cushion to accommodate volume changes of sulfur cathode as well as a barrier to trap soluble polysulfide intermediates during the charge–discharge process. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46544.
X‐ray irradiated LDPE/PP blends with high mechanical and dielectric performance
Authors: Alkan Ümit , Kılıç Mehmet , Karabul Yaşar , Çağlar Mustafa , İçelli Orhan , Güven Özdemir Zeynep 
Published: April 2018

ABSTRACTIn this study, the influences of polypropylene (PP) additive (varying from 20% to 80% wt) and low dose X‐ray irradiation (changing from 25 to 100 Gy) on the mechanical and dielectric properties of low‐density polyethylene (LDPE) were investigated. LDPE/PP film blends were prepared by hot press technique. While the highest Young modulus and tensile strength were observed for the 20%LDPE/80%PP blend at 25 Gy X‐ray irradiation, the same blend had the highest energy at break and percentage strain at break values for 50 Gy X‐ray exposure. These results also indicated a chain scission in the material. The differential scanning calorimetry curves also indicated a chain scission and crosslinking effects in the blends due to X‐ray irradiation. Hence, the higher concentration of PP additive and exposure of low dose X‐ray resulted in a polymer composite with high mechanical performance. On the other hand, the dielectric investigations revealed that the 25 Gy X‐ray irradiated 20%LDPE/80%PP blend may also attract attention for capacitor applications due to its increased static dielectric constant and reduced dielectric loss. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46571.
Synthesis, optical, and thermal properties of polyimides containing flexible ether linkage
Authors: Kaya İsmet , Kamacı Musa 
Published: April 2018

ABSTRACTThe goal of this article was to synthesize a series of flexible polyimides containing ether linkage in main chain and clarified the effect of this ether linkage on some physical properties such as optical and thermal decomposition. Also, different functional group effects such as carbonyl (CO), hexa‐fluoro‐isopropylidene [C(CF3)2] and phenyl (C6H5) on these physical properties were evaluated. The structural characterization of poly(ether imide)s was performed using Fourier transform infrared, 1H‐nuclear magnetic resonance (NMR), and 13C‐NMR techniques. Optical band gap of polyimides was calculated in the range from 2.57 to 2.81 eV. Thermal characterization of poly(ether imide)s was carried out using thermogravimetry–differential thermal analysis and differential scanning calorimetry. Thermal stability of poly(ether imide)s was evaluated by initial decomposition temperature (Ton) and char. Ton value of polymers was determined in the range from 100 to 195 °C. In addition, glass transition temperatures of poly(ether imide)s were found between 144 and 148 °C. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46573.
The synthesis of modified alginate flocculants and their properties for removing heavy metal ions of wastewater
Authors: Tian Zhenle , Zhang Liping , Shi Gang , Sang Xinxin , Ni Caihua 
Published: April 2018

ABSTRACTA new flocculant was synthesized through the modification of sodium alginate with thiosemicarbazide. In the preparation, amino thiourea groups which had excellent adsorption properties for heavy metal ions were introduced to the flocculant. The structure of the flocculant was confirmed by elemental analysis, Fourier transform infrared, UV spectrophotometry, nuclear magnetic resonance, and thermal analysis. The flocculation behaviors of the flocculant for three heavy metal ions were investigated. The results showed that the removal rates of the flocculant for Pb2+, Cd2+, and Cu2+ reached up to 97.8%, 86.3%, and 80.0%, respectively, and the flocculation capacities were as high as 489, 215, and 160 mg/g, respectively. The excellent adsorption was ascribed to the double effects of electronic interaction and chelation between the flocculant and heavy metal ions. The flocculant had particular flocculation selectivity for Pb2+ in the mixed heavy metal ion solutions containing Cd2+or Cu2+, respectively. The flocculation process corresponded to Langmuir isotherm model, the flocculation kinetics agree with pseudo second order. The flocculant had potential applications for treatment of wastewater. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46577.
Contribution of equilibrative nucleoside transporters 1 and 2 to gemcitabine uptake in pancreatic cancer cells
Authors: Hioki Masato , Shimada Takuya , Yuan Tian , Nakanishi Takeo , Tajima Hidehiro , Yamazaki Maiko , Yokono Rina , Takabayashi Makiko , Sawamoto Kazuki , Akashita Gaku , Miyamoto Ken‐Ichi , Ohta Tetsuo , Tamai Ikumi , Shimada Tsutomu , Sai Yoshimichi 
Published: April 2018

AbstractHepatic arterial infusion (HAI) chemotherapy is expected to be a more effective and safer method to treat the hepatic metastasis of pancreatic cancer than intravenous (iv) administration because of higher tumor exposure and lower systemic exposure. To clarify the uptake mechanism of nucleoside anticancer drugs, including gemcitabine (GEM), in pancreatic cancer, we investigated the uptakes of radiolabeled uridine (a general substrate of nucleoside transporters) and GEM in pancreatic cancer cell lines MIA‐PaCa2 and As‐PC1. Uridine uptake was inhibited by non‐labeled GEM and also by S‐(4‐nitrobenzyl)‐6‐thioinosine (NBMPR; an inhibitor of equilibrative nucleoside transporters, ENTs) in a concentration‐dependent manner, suggesting that ENTs contribute to uridine uptake in pancreatic cancer cells. As for GEM, saturable uptake was mediated by high‐ and low‐affinity components with Km values of micromolar and millimolar orders, respectively. Uptake was inhibited in a concentration‐dependent manner by NBMPR and was sodium ion‐independent. Moreover, the concentration dependence of uptake in the presence of 0.1 μM NBMPR showed a single low‐affinity site. These results indicated that the high‐ and low‐affinity sites correspond to hENT1 and hENT2, respectively. The results indicated that at clinically relevant hepatic concentrations of GEM in GEM‐HAI therapy, the metastatic tumor exposure of GEM is predominantly determined by hENT2 under unsaturated conditions, suggesting that hENT2 expression in metastatic tumor would be a candidate biomarker for indicating anticancer therapy with GEM‐HAI.
The effect of active participation on performance and understanding on the Iowa gambling task
Authors: Vanhille Sean , Palmer Brittany , Hayes William , Overman William 
Published: April 2018

AbstractThe Iowa gambling task (IGT) was developed as a neuropsychological assessment of “real‐life” decision making in a laboratory setting by Bechara, Damasio, Damasio, and Anderson in . The IGT was originally implemented as a manual task during which the participants selected paper cards. The task has since evolved into a computerized assessment tool (Psychological Assessment Resources IGT or PAR™IGT) that uses only virtual cards and reinforcement schedules that are somewhat different from those in the original version. Caution should be used when psychological assessments change from manual to virtual formats. Such changes may unintentionally introduce confounds that render the 2 tests nonequivalent as shown with the Wisconsin Card Sorting Task by Steinmetz, Brunner, Loarer, and Houssemand in . In this study, we compared IGT performance when participants used either a laptop computer or a touchscreen tablet. Each device was used in 2 conditions: “involved” and “noninvolved.” Participants in the involved condition turned over physical cards and mimicked their own selections by clicking (laptop) or reaching out and touching (tablet) the corresponding virtual cards. Participants in the noninvolved condition only made selections of virtual cards, whereas an adjacent experimenter turned over the corresponding physical cards. Results showed that performance systematically and significantly improved as degree of physical involvement increased in the following order: laptop noninvolved (lowest performance), tablet noninvolved, laptop involved, and tablet involved (highest performance). In addition, participants' verbalized understanding of the task was significantly more accurate with increased physical involvement.
Randomized clinical trial of elective resection versus observation in diverticulitis with extraluminal air or abscess initially managed conservatively
Authors: You K , Bendl R , Taut C , Sullivan R , Gachabayov M , Bergamaschi R , Connolly T M , Yang K , Giuratrabocchetta S , Denoya P I , Zawin M , Ferretti J , Baer A , Wertheim W 
Published: April 2018

Abstract

Background
The aim of this RCT was to determine whether elective resection following successful non-operative management of a first episode of acute sigmoid diverticulitis complicated by extraluminal air with or without abscess is superior to observation in terms of recurrence rates.

Methods
This was a single-centre, sequential design RCT. Patients were randomized to elective surgery or observation following non-operative management and colonoscopy. Non-operative management included nil by mouth, intravenous fluids, intravenous antibiotics, CT with intravenous contrast on arrival at hospital, and repeat CT with intravenous and rectal contrast on day 3 in hospital. The primary endpoint was recurrent diverticulitis at 24 months. Patients with a history of sigmoid diverticulitis, immunosuppression or peritonitis were not included.

Results
Of 137 screened patients, 107 were assigned randomly to elective surgery (26) or observation (81), and underwent the allocated intervention after successful non-operative management. Conservative management failed in 15 patients. Groups were similar in age, sex, BMI, co-morbidities and colorectal POSSUM. Rates of recurrent diverticulitis differed significantly in the elective surgery and observation groups (8 versus 32 per cent; P = 0·019) at a mean(s.d.) follow-up of 37·8(8·6) and 35·2(9·2) months respectively. There was also a significant difference in time to recurrence (median 11 versus 7 months; P = 0·015). A total of 28 patients presented with recurrent diverticulitis complicated by extraluminal air and/or abscess (2 elective surgery, 26 observation), all of whom recovered with repeat non-operative management.

Conclusion
The majority of patients observed following conservative management of diverticulitis with local extraluminal air do not require elective surgery. Registration number: NCT01986686 (http://www.clinicaltrials.gov).
Celecoxib enhances the therapeutic efficacy of epirubicin for Novikoff hepatoma in rats
Authors: Chu Tian‐Huei , Chan Hoi‐Hung , Hu Tsung‐Hui , Wang E‐Ming , Ma Yi‐Ling , Huang Shih‐Chung , Wu Jian‐Ching , Chang Yi‐Chen , Weng Wen‐Tsan , Wen Zhi‐Hong , Wu Deng‐Chyang , Chen Yi‐Ming Arthur , Tai Ming‐Hong 
Published: April 2018

AbstractEpirubicin is a chemotherapy agent for hepatocellular carcinoma (HCC). However, the outcome of HCC patients receiving epirubicin remains unsatisfactory. Moreover, our previous study indicated that celecoxib suppresses HCC progression and liver cancer stemness. This study evaluated the potential of celecoxib to serve as a complementary therapy during epirubicin treatment. Cell proliferation, apoptosis, invasiveness, and anchorage‐independent growth were analyzed in hepatoma cells. Therapeutic efficacy was validated in rat orthotopic Novikoff hepatoma. After animal sacrifice, the antitumor mechanism of celecoxib and epirubicin combined therapy was investigated by histological analysis. Celecoxib enhanced the cytotoxic activity of epirubicin in HCC cells by promoting apoptosis. Besides, celecoxib potentiated the antineoplastic function of epirubicin in inhibiting the invasiveness and anchorage‐independent growth of HCC cells. Ultrasound monitoring showed that combined therapy was more potent than either therapy alone in perturbing HCC progression. Consistently, the size and weight of dissected HCC tissues from rats receiving combined therapy were smallest among all groups. HCC treated with combined therapy exhibited the highest prevalence of apoptotic cells, which was accompanied by reduced proliferating and angiogenic activities in tumor tissues. Moreover, the expression levels of cancer stemness markers (CD44 and CD133) and drug transporter MDR‐1 were significantly diminished in rats receiving combined therapy. Besides, celecoxib treatment increased the infiltration of cytotoxic T lymphocytes (CTLs) and reduced the number of regulatory T cells (Tregs), tumor‐associated macrophages (TAMs), and the expression of immune checkpoint PD‐L1 in HCC tissues during epirubicin therapy. Celecoxib augmented the therapeutic efficacy while modulated cancer stemness and antitumor immunity. Thus, celecoxib may serve as complementary therapy to improve the outcome of patients with advanced HCC during epirubicin treatment.
Ultra‐Stable and High‐Cobalt‐Loaded Cobalt@Ordered Mesoporous Carbon Catalysts: All‐in‐One Deoxygenation of Ketone into Alkylbenzene
Authors: Zhang Pengfei , Chen Nanqing , Chen Dong , Yang Shize , Liu Xiaofei , Wang Li , Wu Peiwen , Phillip Nathan , Yang Guang , Dai Sheng 
Published: April 2018

AbstractCatalytic deoxygenation represents a straightforward and core methodology for fine‐chemical production and biomass upgrading. Generally, the application of homogeneous metal complexes or heterogeneous noble‐metal catalysts prevails in academia and the chemical industry. Herein, we introduce cobalt@ordered mesoporous carbon (Co@OMC) catalysts, which are constructed conveniently by a mechanochemical coordination self‐assembly based on a renewable tannin precursor. Importantly, the Co@OMC catalysts with a high loading of in situ confined Co species promote the selective deoxygenation of various ketones, aldehydes, and alcohols efficiently into the corresponding alkanes under mild conditions. Therefore, a simple, inexpensive, and heterogeneous catalyst for selective deoxygenation can be expected, meanwhile the solid‐state synthesis affords a green, rapid, and scalable pathway to Co@OMC catalysts.
Mixed Valent, Distorted Cobalt Ludwigite (Co3BO5/Co3O2BO3) and Its Composite with Reduced Multiwalled Carbon Nanotubes (R‐MWCNT) in Enhancing the Domain Edge‐Sharing Oxygen as Superior Water Oxidation Electrocatalysts
Authors: Kundu Sumana , Malik Bibhudatta , Pattanayak Deepak K. , Pillai Vijayamohanan K. 
Published: April 2018

AbstractHerein, we report, a hybrid of mixed valent cobalt ludwigite (Co3BO5) and reduced‐multiwalled carbon nanotubes (R‐MWCNTs) as an outstanding oxygen evolution reaction (OER) electrocatalyst. Interestingly, the composite acts as a potential OER electrocatalyst, displaying a low overpotential of 270 mV @10 mA cm−2, which is lower than that for the state‐of‐the‐art RuO2 catalyst. The remarkable OER performance of the cobalt‐ludwigite is attributed to its basic distorted open crystal structure, which has a relatively high crystal volume, owing to a domain network consisting of edge‐sharing octahedra. Moreover, X‐ray photoelectron spectroscopy clarifies the hybrid of cobalt‐ludwigite and R‐MWCNTs, exhibiting a stable π‐cation‐like interaction between the Co3+ of Co3BO5 rather than Co2+ and neutral π‐ cloud of R‐MWCNTs, which helps in enhancing the conductivity of the system. Thus, the overall performance of the composite stems from the basic crystal structure of the Co3BO5 and the existence of synergistic effects between the R‐MWCNTs on Co3BO5 through π‐cation‐like interaction. Hence, the results of this study might be useful in developing more efficient other ludwigite–carbon OER electrocatalysts as affordable alternatives.