bluuebunny/crossref_metadata_2025_split huggingface dataset:
Strengthening mechanism of poly(acrylamide)/graphene oxide/laponite dual nanocomposite hydrogels
Authors: Ling Jing , Li Na , Yang Xue , Ma Jianjun , Du Juan , Wang Di , Tan Yun , Yue Fan , Xu Shimei 
Published: February 2017

ABSTRACTLaponite or graphene oxide (GO) is usually used as a multifunctional crosslinker or a nanofiller to improve the nanocomposite gel strength. To explore the strengthening mechanism of GO/Laponite‐based dual nanocomposite hydrogels, we synthesized a dual nanocomposite hydrogel through in situ polymerization of acrylamide (AM) in the dispersion of GO and Laponite. The interactions between GO and Laponite were confirmed by rheological test. GO and Laponite nanosheets were exfoliated well and dispersed uniformly in the hydrogels at low concentration of GO. Crosslinking network and thermal behaviors were investigated with respect to the concentration of GO and Laponite. The gel exhibited a high mechanical strength of 391 kPa with extensibility of 1420% and a high toughness of 2.58 MJ/m3, which was expected to be applied in biological engineering field. GO is not a much more effective agent than Laponite due to formation of GO aggregates in high concentration of GO. This work provides a guidance for the synthesis of tough dual nanocomposite hydrogels. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44963.
Jumping Crystals of Pyrene Tweezers: Crystal‐to‐Crystal Transition Involving π/π‐to‐CH/π Assembly Mode Switching
Authors: Shibuya Yoshiki , Itoh Yoshimitsu , Aida Takuzo 
Published: February 2017

AbstractCrystals of pyrene tweezers 1 with interdigitating pyrenyl blades jump vigorously at around 160 °C. Single‐crystal X‐ray diffraction analysis before jumping revealed the presence of a “pyrene tetrad” in the crystal lattice, where four pyrenyl blades are π‐stacked on top of each other. Upon heating the crystal to induce the jumping event, inner two pyrenyl blades in the “pyrene tetrad” probably rotate to switch off their π‐stacking interaction with the neighboring outer pyrenyl blades and form new CH−π bonds. Different from reported salient crystals, our crystal jumps with the release of CHCl3 as inclusion solvent.
Molten Ag2SO4‐based Ion‐Exchange Preparation of Ag0.5La0.5TiO3 for Photocatalytic O2 Evolution
Authors: Zong Shichao , Cheng Cheng , Shi Jinwen , Huang Zhenxiong , Hu Yuchao , Yang Honghui , Guo Liejin 
Published: February 2017

AbstractAg0.5La0.5TiO3 with an ABO3 perovskite structure was synthesized by a newly developed ion‐exchange method. Molten Ag2SO4 instead of traditional molten AgNO3 was used as Ag+ source in view of its high decomposition temperature (1052 °C), thereby guaranteeing the complete substitution of Ag+ for Na+ in Na0.5La0.5TiO3 with a stable ABO3 perovskite structure at a high ion‐exchange temperature (700 °C). Under full‐arc irradiation, the O2‐evolution activity of Ag0.5La0.5TiO3 was about 1.6 times that of Na0.5La0.5TiO3 due to the optimized electronic band structures and local lattice structures. On the one hand, the substitution of Ag+ for Na+ elevated the VBM and thus narrowed the band gap from 3.19 to 2.83 eV, thereby extending the light‐response range and, accordingly, enhancing the photoexcitation to generate more charge carriers. On the other hand, the substitution of Ag+ for Na+ induced a lattice distortion of the ABO3 perovskite structure, thereby promoting the separation and migration of charge carriers. Moreover, under visible‐light irradiation, Ag0.5La0.5TiO3 displayed notable O2 evolution whereas Na0.5La0.5TiO3 showed little O2 evolution, thus demonstrating that the substitution of Ag+ for Na+ enabled the use of visible light to evolve O2 photocatalytically. This work presents an effective route to explore novel Ag‐based photocatalysts.
Variable Gain Output Feedback Control of A Networked Temperature Control System Based on Online Delay Estimation
Authors: Suryendu Chhavi , Ghosh Sandip , Subudhi Bidyadhar 
Published: February 2017

AbstractIn this paper, a gradient descent method based delay estimator is proposed for use with a variable gain control strategy for networked control systems. The delay estimator is developed in such a way that its boundedness is ensured. The performance of the estimator with variable gain controller is evaluated on a temperature control plant with network in the feedback loop.
Statistical Analysis of Power System Sensitivity Under Random Penetration of Photovoltaic Generation
Authors: Li Yu , Ishikawa Masato 
Published: February 2017

AbstractIn this paper, we aim to analyze the characteristics of feeder voltage variation in power systems due to random allocation of solar photovoltaic systems from a data‐driven approach, search the dangerous photovoltaic system allocation patterns along a specific power system. We conducted the investigation on benchmark radial distribution circuits with a random integration of certain amount of photovoltaic systems. Severe voltage deviation occurs along the tail part of each circuit line, and the connecting nodes between feeder and lateral circuit lines tend to be vulnerable to the integration of photovoltaic systems. Different allocation patterns of photovoltaic systems resulted in a data set of voltage variation in the distribution system, k‐Medoids clustering algorithm was proposed in this study to partition this data set into several clusters, which would contribute to the search of photovoltaic system allocation patterns with similar voltage deviation response.
A comparative investigation of Bombyx mori silk fibroin hydrogels generated by chemical and enzymatic cross‐linking
Authors: Chirila Traian V. , Suzuki Shuko , Papolla Chloé 
Published: February 2017

AbstractFibroin, the major proteinaceous component of the silk fiber produced by larvae of the domesticated silk moth (Bombyx mori), has been widely investigated as a biomaterial for potential applications in tissue engineering and regenerative medicine. Following sol–gel transition, silk fibroin solutions can generate hydrogels that present certain advantages when employed as biomaterials, especially if they are cross‐linked. The subject of this study was the self‐cross‐linking of silk fibroin through a process induced by the enzyme horseradish peroxidase (HRP) in the presence of hydrogen peroxide, a method only recently proposed and scarcely reported. The hydrogels were prepared either by physical cross‐linking, by cross‐linking with a natural compound (genipin), or by enzymatic cross‐linking. The products were comparatively characterized in regard to their synthesis and background chemical aspects, physical and optical properties, mechanical properties, secondary structure, swelling/deswelling behavior, enzymatic degradation, and compatibility as substrates for cell adhesion and proliferation. The study confirmed the advantages of the HRP‐induced cross‐linking, which included considerably shorter gelation times, enhanced elasticity of the resulting hydrogels, and improved cytocompatibility. Discrepancies between certain results of this investigation and those reported previously were discussed in detail.
Phosphor for phototherapy: Review on psoriasis
Authors: Hemne P. S. , Kunghatkar R. G. , Dhoble S. J. , Moharil S. V. , Singh V. 
Published: February 2017

AbstractWe review developments in the field of phototherapy in terms of the treatment wavelength, dosimetry and phosphor used for different dermatoses. We attempt to categorize skin lesions and diseases by morphology, focusing on conditions that can be treated using phototherapy and photochemotherapy. Recent research and review articles are studied, the treatments explained and information on phototherapy that is applicable to psoriasis and other diseases is tabulated. The clinical features, epidemiology, epitalogy and various types of psoriasis, together with the therapies available to treat them are reported. Needs‐based research has been carried out on narrow and broad band UVB wavelength‐emitting phosphors and psoralen combined with UVA (PUVA) depending upon the disease undergoing treatment. Somewhat detailed descriptions of the different types of therapies used in the treatment of psoriasis are given. Phototherapy is shown to be a good therapeutic option for various types of skin diseases. The use of natural therapy has diminished as more people move towards artificial phototherapy like narrow band UVB, broad band UVB, PUVA and targeted phototherapy. The main advantages of these treatments are that they are safe and reduce erythema following treatment. Regarding safety issue the targated phototherapy pay more attention towards researcher.
Insights into the discrepant luminescence for BaSiO3:Eu2+ phosphors prepared by solid‐state reaction and precipitation reaction methods
Authors: Xu Jiao , Zhao Yang , Chen Jingjing , Mao Zhiyong , Yang Yanfang , Wang Dajian 
Published: February 2017

AbstractTwo synthesis routes, solid‐state reaction and precipitation reaction, were employed to prepare BaSiO3:Eu2+ phosphors in this study. Discrepancies in the luminescence green emission at 505 nm for the solid‐state reaction method sample and in the yellow emission at 570 nm for the sample prepared by the precipitation reaction method, were observed respectively. A detail investigation about the discrepant luminescence of BaSiO3:Eu2+ phosphors was performed by evaluation of X‐ray diffraction (XRD), photoluminescence (PL)/photoluminescence excitation (PLE), decay time and thermal quenching properties. The results showed that the yellow emission was generated from the BaSiO3:Eu2+ phosphor, while the green emission was ascribed to a small amount of Ba2SiO4:Eu2+ compound that was present in the solid‐state reaction sample. This work clarifies the luminescence properties of Eu2+ ions in BaSiO3 and Ba2SiO4 hosts.
Comparison and analysis on the serum‐binding characteristics of aspirin–zinc complex and aspirin
Authors: Zhang Hua‐xin , Zhang Qun , Wang Hong‐lin , Li Li‐wei 
Published: February 2017

AbstractThis study was designed to compare the protein‐binding characteristics of aspirin–zinc complex (AZN) with those of aspirin itself. AZN was synthesized and interacted with a model transport protein, human serum albumin (HSA). Three‐dimensional fluorescence, ultraviolet–visible and circular dichroism (CD) spectra were used to characterize the interaction of AZN with HSA under physiological conditions. The interaction mechanism was explored using a fluorescence quenching method and thermodynamic calculation. The binding site and binding locality of AZN on HSA were demonstrated using a fluorescence probe technique and Förster non‐radiation energy transfer theory. Synchronous fluorescence and CD spectra were employed to reveal the effect of AZN on the native conformation of the protein. The HSA‐binding results for AZN were compared with those for aspirin under consistent experimental conditions, and indicated that aspirin acts as a guide in AZN when binding to Sudlow's site I, in subdomain IIA of the HSA molecule. Moreover, compared with aspirin, AZN showed greater observed binding constants with, but smaller changes in the α‐helicity of, HSA, which proved that AZN might be easier to transport and have less toxicity in vivo.
Development of hydrogels for regenerative engineering
Authors: Guan Xiaofei , Avci‐Adali Meltem , Alarçin Emine , Cheng Hao , Kashaf Sara Saheb , Li Yuxiao , Chawla Aditya , Jang Hae Lin , Khademhosseini Ali 
Published: February 2017

AbstractThe aim of regenerative engineering is to restore complex tissues and biological systems through convergence in the fields of advanced biomaterials, stem cell science, and developmental biology. Hydrogels are one of the most attractive biomaterials for regenerative engineering, since they can be engineered into tissue mimetic 3D scaffolds to support cell growth due to their similarity to native extracellular matrix. Advanced nano‐ and micro‐technologies have dramatically increased the ability to control properties and functionalities of hydrogel materials by facilitating biomimetic fabrication of more sophisticated compositions and architectures, thus extending our understanding of cell‐matrix interactions at the nanoscale. With this perspective, this review discusses the most commonly used hydrogel materials and their fabrication strategies for regenerative engineering. We highlight the physical, chemical, and functional modulation of hydrogels to design and engineer biomimetic tissues based on recent achievements in nano‐ and micro‐technologies. In addition, current hydrogel‐based regenerative engineering strategies for treating multiple tissues, such as musculoskeletal, nervous and cardiac tissue, are also covered in this review. The interaction of multiple disciplines including materials science, cell biology, and chemistry, will further play an important role in the design of functional hydrogels for the regeneration of complex tissues.
Lepra‐Erreger in britischen Eichhörnchen
Authors: Bosch Stefan , Lurz Peter W.W. , Meredith Anna L. 
Published: February 2017

ZusammenfassungAuf den Britischen Inseln wurden bei Eichhörnchen mit Haut‐ und Fellveränderungen zwei Erreger der Lepra (Mycobacterium leprae und M. lepromatosis) als Ursache nachgewiesen. M. lepromatosis wurde erstmals 2008 beim Menschen und 2014 erstmals bei einem Tier überhaupt in einem schottischen Eichhörnchen entdeckt. Vermutlich kursieren die Erreger in manchen Gebieten schon seit Jahrzehnten unter den Eichhörnchen, wobei unklar ist, wie die Erreger in die Eichhörnchen gelangten. Aktuelle Forschung soll die Verbreitung und einen möglichen Einfluss auf die ohnehin bedrohten britischen Bestände klären.
Pyrrole Derivatives and Diterpene Alkaloids from the South China Sea Sponge Agelas nakamurai
Authors: Chu Mei‐Jun , Tang Xu‐Li , Qin Guo‐Fei , Sun Yan‐Ting , Li Lei , de Voogd Nicole J. , Li Ping‐Lin , Li Guo‐Qiang 
Published: February 2017

Two pairs of new non‐brominated racematic pyrrole derivatives, (±)‐nakamurine D (1) and (±)‐nakamurine E (2), two new diterpene alkaloids, isoagelasine C (16) and isoagelasidine B (21), together with 13 known pyrrole derivatives ((±)‐3 – 15), five known diterpene alkaloids (17 – 20, 22) were isolated from the South China Sea sponge Agelas nakamurai. The racemic mixtures, compounds 1 – 4, were resolved into four pairs of enantiomers, (+)‐1 and (−)‐1, (+)‐2 and (−)‐2, (+)‐3 and (−)‐3, and (+)‐4 and (−)‐4, by chiral HPLC. The structures and absolute configurations were elucidated on the basis of comprehensive spectroscopic analyses, quantum chemical calculations, quantitative measurements of molar rotations, application of van't Hoff's principle of optical superposition, and comparison with the literature data. The NMR and MS data of compound 3 are reported for the first time, as the structure was listed in SciFinder Scholar with no associated reference. These non‐brominated pyrrole derivatives were found in this species for the first time. Compound 18 showed valuable cytotoxicities against HL‐60, K562, and HCT‐116 cell lines with IC50 values of 12.4, 16.0, and 19.8 μm, respectively. Compounds 16 – 19, 21, and 22 showed potent antifungal activities against Candida albicans with MIC values ranging from 0.59 to 4.69 μg/ml. Compounds 16 – 19 exhibited moderate antibacterial activities against Proteusbacillus vulgaris (MIC values ranging from 9.38 to 18.75 μg/ml).
Quantitative PCR is a Valuable Tool to Monitor the Performance of DNA‐Encoded Chemical Library Selections
Authors: Li Yizhou , Zimmermann Gunther , Scheuermann Jörg , Neri Dario 
Published: February 2017

AbstractPhage‐display libraries and DNA‐encoded chemical libraries (DECLs) represent useful tools for the isolation of specific binding molecules from large combinatorial sets of compounds. With both methods, specific binders are recovered at the end of affinity capture procedures by using target proteins of interest immobilized on a solid support. However, although the efficiency of phage‐display selections is routinely quantified by counting the phage titer before and after the affinity capture step, no similar quantification procedures have been reported for the characterization of DECL selections. In this article, we describe the potential and limitations of quantitative PCR (qPCR) methods for the evaluation of selection efficiency by using a combinatorial chemical library with more than 35 million compounds. In the experimental conditions chosen for the selections, a quantification of DNA input/recovery over five orders of magnitude could be performed, revealing a successful enrichment of abundant binders, which could be confirmed by DNA sequencing. qPCR provided rapid information about the performance of selections, thus facilitating the optimization of experimental conditions.
Non‐coding RNAs: emerging regulatory factors in the derivation and differentiation of mammalian parthenogenetic embryonic stem cells
Authors: Cui Jihong , Xie Xin 
Published: February 2017

AbstractParthenogenetic embryonic stem cells (PESCs) are ESCs derived from early parthenogenetic embryos. Haploid PESCs, containing haploid DNA, originate from a single sperm or occyte, while, diploid PESCs originate from two fused occytes. Most PESC lines used so far are diploid. PESCs exhibit representative pluripotent stem cell features, such as the capacity for self‐renewal and the pariticular molecular signatures. Whereas, PESCs display distinctive properties, such as differential regulation of X‐chromosome inactivation (XCI) and divergent monitor of genes involved in multiple biological processes. PESCs are considered promising in the regeneration medicine and developmental biology. Non‐coding RNAs (ncRNAs), especially miRNAs and lncRNAs, have garnered increasing attention over the past 2 decades. They are now known to be involved in almost all cellular processes due to their full‐range regulation of gene expression. Numerous studies have indicated that embryonic stem cells (ESCs) displayed distinct signatures of ncRNA genes, which play key roles in the pluripotency and self renewal of ESCs. However, the expression pattern of ncRNAs in PESCs and their roles in the derivation and differentiation of PESCs were rarely reported. In this paper, we reviewed recent research on the derivation and differentiation of PESCs and describe the emerging role of ncRNAs in these processes.
Transcatheter aortic valve replacement and renal function: A complex relationship
Authors: James Rodriguez Ruben , Prasad Anand 
Published: February 2017

Key Points

The baseline severity of chronic kidney disease appears related to the risk of acute kidney injury following transcatheter aortic valve replacement (TAVR).
Severity of AKI is related to increased risk of mortality following TAVR.
The pathophysiology of AKI and its impact on mortality in TAVR patients remains unclear.
Catalytic Stability Study of a Pd‐Ni2P/C Catalyst for Formic Acid Electrooxidation
Authors: Wang Shuli , Chang Jinfa , Xue Huaiguo , Xing Wei , Feng Ligang 
Published: February 2017

AbstractIn this work, the catalytic stability of Pd‐Ni2P/C, a highly efficient anode catalyst for direct formic acid fuel cells, was studied by using electrochemical and physical techniques. The dynamic stability was probed in an accelerated stability test (AST) by using cyclic voltammetry for 1000 cycles, and a very low performance decay rate was observed on the Pd‐Ni2P/C catalyst compared with a homemade Pd/C catalyst. About 60 % of the initial peak current density, three times higher than that of the homemade Pd/C catalyst, was retained after the AST on the Pd‐Ni2P/C catalyst. There were no obvious structure and morphology changes in the Pd‐Ni2P/C catalyst revealed by X‐ray diffraction, X‐ray photoelectron spectroscopy, or transmission electron microscopy characterization. However, largely increased Pd particle sizes that appear on the Pd/C catalyst might lead to serious performance decay. The strong interaction of Pd and Ni2P in the catalyst system might increase the anchoring of Pd nanoparticles on the support surface, thus less Pd was lost during electrocatalysis. Steady‐state stability tests further confirmed the high stability of the Pd‐Ni2P/C catalyst, and the high anti‐poisoning ability to CO‐like intermediates would maintain the high stability. The results are important for an in‐depth understanding of the contribution of Ni2P in the catalyst system.
Hydrogen‐Atom Transfer (HAT) Initiated by Intramolecular Ligand–Metal Electron Transfer
Authors: Herrmann Hendrik , Kaifer Elisabeth , Himmel Hans‐Jörg 
Published: February 2017

AbstractHydrogen‐atom transfer (HAT) is of key importance for several catalytic and biological processes, and provides an elegant access to C−H activation. In synthetic chemistry, a photoactivated metal complex is often employed to abstract an oxygen‐ or nitrogen‐bound hydrogen, and the as‐generated oxygen‐ or nitrogen‐centered radical is the hydrogen‐atom acceptor for HAT. Here, we report the first examples for HAT processes initiated by one‐electron oxidation of urea azines. A further novelty is that the HAT‐initiating oxidation can be realized by intramolecular ligand–metal electron transfer in copper(II)‐urea azine complexes. These complexes are first characterized in the solid state, in which they are stable. Electron‐transfer‐initiated HAT processes are observed upon dissolving the complexes in organic solvents, and the kinetics of these processes varies with the solvent polarity. The carbon‐centered radicals formed by HAT can either be trapped with 2,2,6,6‐tetramethylpiperidinyloxyl (TEMPO) or undergo radical recombination reactions with itself, yielding diamagnetic end‐products.
Confining for Stability: Heterogeneous Catalysis with Transition Metal (Oxide) Nanoparticles Confined in the Secondary Pore Network of Mesoporous Scaffolds
Authors: Ciotonea Carmen , Mazilu Irina , Dragoi Brindusa , Catrinescu Cezar , Dumitriu Emil , Ungureanu Adrian , Alamdari Houshang , Petit Sabine , Royer Sébastien 
Published: February 2017

AbstractA melt infiltration strategy allows the encapsulation of transition metal (oxide) nanoparticles in the intra‐wall pores of SBA‐15 supports, providing ultrafine particles that are stable at high temperatures (up to 900 °C, oxidizing–reducing atmospheres). Selective localization of transition metal (oxide) precursor in the secondary pores is achieved in the presence of organic structure‐directing agent occluded in the intra‐wall pores, and by applying an intermediate diffusion step during preparation.
A parallel C4.5 decision tree algorithm based on MapReduce
Authors: Mu Yashuang , Liu Xiaodong , Yang Zhihao , Liu Xiaolin 
Published: February 2017

SummaryIn the supervised classification, large training data are very common, and decision trees are widely used. However, as some bottlenecks such as memory restrictions, time complexity, or data complexity, many supervised classifiers including classical C4.5 tree cannot directly handle big data. One solution for this problem is to design a highly parallelized learning algorithm. Motivated by this, we propose a parallelized C4.5 decision tree algorithm based on MapReduce (MR‐C4.5‐Tree) with 2 parallelized methods to build the tree nodes. First, an information entropy‐based parallelized attribute selection method (MR‐A‐S) on several subsets for MR‐C4.5‐Tree is proposed to confirm the best splitting attribute and the cut points. Then, a data splitting method (MR‐D‐S) in parallel is presented to partition the training data into subsets. At last, we introduce the MR‐C4.5‐Tree learning algorithm that grows in a top‐down recursive way. Besides, the depth of the constructed decision tree, the number of samples and the maximal class probability in each tree node are used as the termination conditions to avoid the over‐partitioning problem. Experimental studies show the feasibility and the good performance of the proposed parallelized MR‐C4.5‐Tree algorithm.