bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioengineering strategies to generate artificial protein complexes
Authors: Kim Heejae , Siu Ka‐Hei , Raeeszadeh‐Sarmazdeh Maryam , Sun Qing , Chen Qi , Chen Wilfred 
Published: May 2015

ABSTRACTFor many applications, increasing synergy between distinct proteins through organization is important for the specificity, regulation, and overall reaction efficiency. Although there are many examples of protein complexes in nature, a generalized method to create these complexes remains elusive. Many conventional techniques such as random chemical conjugation, physical adsorption onto surfaces, and encapsulation within matrices are imprecise approaches and can lead to deactivation of protein native functionalities. More “bio‐friendly” approaches such as genetically fused proteins and biological scaffolds often can result in low yields and low complex stability. Alternatively, site‐specific protein conjugation or ligation can generate artificial protein complexes that preserve the native functionalities of protein domains and maintain stability through covalent bonds. In this review, we describe three distinct methods to synthesize artificial protein complexes (genetic incorPoration of unnatural amino acids to introduce bio‐orthogonal azide and alkyne groups to proteins, split‐intein based expressed protein ligation, and sortase mediated ligation) and highlight interesting applications for each technique. Biotechnol. Bioeng. 2015;112: 1495–1505. © 2015 Wiley Periodicals, Inc.
Coagulopathy and functional hyposplenism during an episode of thrombotic thrombocytopenic purpura in a HgbS/β+‐thalassemia patient
Authors: Gangemi Andrew J. , Pickens Peter V. 
Published: May 2015

Key Clinical MessageWe report a case of TTP in a sickle cell/β+‐thalassemia heterozygote with nonspecific complaints and a evidence of hemolysis, initially attributed to sickle crisis. Included in this case is a discussion of the development of functional hyposplenism, a rarely reported complication, limitation of ADAMTS‐13 in diagnosis, and the use of platelet transfusion.
Dissolution of Platinum in the Operational Range of Fuel Cells
Authors: Cherevko Serhiy , Keeley Gareth P. , Geiger Simon , Zeradjanin Aleksandar R. , Hodnik Nejc , Kulyk Nadiia , Mayrhofer Karl J. J. 
Published: May 2015

AbstractOne of the most important practical issues in low‐temperature fuel‐cell catalyst degradation is platinum dissolution. According to the literature, it initiates at 0.6–0.9 VRHE, whereas previous time‐ and potential‐resolved inductively coupled plasma mass spectrometry (ICP–MS) experiments, however, revealed dissolution onset at only 1.05 VRHE. In this manuscript, the apparent discrepancy is addressed by investigating bulk and nanoparticulated catalysts. It is shown that, given enough time for accumulation, traces of platinum can be detected at potentials as low as 0.85 VRHE. At these low potentials, anodic dissolution is the dominant process, whereas, at more positive potentials, more platinum dissolves during the oxide reduction after accumulation. Interestingly, the potential and time dissolution dependence is similar for both types of electrode. Dissolution processes are discussed with relevance to fuel‐cell operation and plausible dissolution mechanisms are considered.
Direct Enantioselective Vinylogous Mannich Reaction of Ketimines with γ‐Butenolide by Using Cinchona Alkaloid Amide/Zinc(II) Catalysts
Authors: Nakamura Shuichi , Yamaji Ryota , Hayashi Masashi 
Published: May 2015

AbstractA direct enantioselective vinylogous Mannich reaction of ketimines with γ‐butenolide has been developed. Good yields and enantioselectivities were observed for the reaction of various ketimines by using a cinchona alkaloid amide/Zn(OTf)2 catalyst and Et3N. Both enantiomers of the products could be obtained by using pseudoenantiomeric chiral catalysts.
New Core‐Shell Type Polymeric Supports Based on the Amberlite XAD‐4 Adsorbent: A Novel Synthesis Procedure
Authors: Cyganowski Piotr , Jermakowicz‐Bartkowiak Dorota , Chęcmanowski Jacek , Kujawska Małgorzata , Bryjak Marek 
Published: May 2015

AbstractThe chloromethyl groups have been introduced into commercial S/DVB copolymer matrixes via interpenetrating polymer networks (IPN) synthesis. The procedure involves impregnation of the Amberlite XAD‐4 adsorbent, with use of the vinylbenzyl chloride (VBC) and divinylbenzene (DVB) monomers mixture, and suspension polymerization process. The syntheses were evaluated by FT‐IR spectra and SEM analyses and furthermore by chlorine content determination as well as characterization of porous structure by nitrogen adsorption at liquid nitrogen temperature. Designed synthesis approach allowed determining organic and water phases composition. Furthermore, impact of an excess of the organic phase removal method has been investigated. Basing on the obtained results it could be stated that the chloromethyl groups, derived from VBC monomer, were successfully introduced into the XAD‐4 structure. Captured SEM images revealed significant changes in the beads' surface morphology after polymerization processes. The presented studies reveal designed and executed synthesis processes, which involve the use of a proper water phase and excess of organic phase removal. Observed changes in the beads' morphology suggest that introduced functionalities are concentrated on the porous surface of the XAD‐4 adsorbent.
Palladium‐Catalyzed Direct C2‐ and Further C7‐Acylation of Indoles with Aldehydes
Authors: Zhang Hui‐Jun , Wu Zhengjian , Lin Weidong , Wen Ting‐Bin 
Published: May 2015

AbstractThe palladium‐catalyzed direct C2‐ and further C7‐acylation of indoles with aldehydes have been developed. This method provides a convenient pathway toward a variety of mono‐ and diacylated indoles.
One‐Step Synthesis of Graphene/Polyaniline Nanotube Composite for Supercapacitor Electrode
Authors: Fan Xin , Yang Zhewei , Liu Zheng 
Published: May 2015

AbstractGraphene/polyaniline nanotube (GPNT) composite was synthesized using Vitamin C as both the template of polyaniline nanotube via in situ polymerization of aniline and the reducing agent of graphene oxide. The pure polyaniline (PANI), graphene/PANI composite (GP) (using hydrazine monohydrate instead of VC) and GO/PANI composite were also prepared. IR spectroscopy and morphologies of the as‐prepared samples were characterized. And the electrochemical performances were conducted on a three‐electrode cell. IR spectroscopy demonstrated the interaction between graphene and PANI nanotube in GPNT, which is beneficial to enhance the electrochemical performance of the composite electrode. Surface morphology showed PANI nanotube with outer diameter of 140 nm in GPNT. GPNT composites exhibited better electrochemical performances than GP composite and pure PANI. The electrochemical performances showed that the specific capacitance of GPNT was 561 F/g which is more than that of either GP or PANI, it is not only due to the graphene which can provide good electrical conductivity and high specific surface area, but also associated with a good redox activity of ordered PANI nanotubes. The as‐prepared GPNT composites with higher conductivity, lower resistance and better cycle life in our laboratory are promising electrode materials for high‐performance electrical energy storage devices.
Efficient Copper‐Catalyzed Annulation of 2‐Formylazoles with 2‐Haloanilines for the Synthesis of Pyrrole‐ and Imidazole‐Fused Quinoxalines
Authors: Li Zihao , Yan Nannan , Xie Jianwei , Liu Ping , Zhang Jie , Dai Bin 
Published: May 2015

AbstractPromoted by CuI/2‐hydroxybenzohydrazide catalytic system, a variety of pyrrole‐ and imidazole‐fused quinoxalines have been efficiently one‐pot synthesized from pyrrole‐/imidazole‐2‐carboxaldehyde and 2‐haloanilines in moderate to excellent yields.
An Improved Turn‐On Aptasensor for Thrombin Detection Using Split Aptamer Fragments and Graphene Oxide
Authors: Liu Xingfen , Yang Yonghong , Hua Xiaoxiao , Feng Xiaomiao , Su Shao , Huang Yanqin , Fan Quli , Wang Lianhui , Huang Wei 
Published: May 2015

AbstractAn improved turn‐on aptasensor for thrombin detection using split aptamer fragments and graphene oxide (GO) was reported. The thrombin‐binding aptamer (Apt15) was split into two parts for target recognition, an 8‐base sequence labeled with fluorescein (FAM‐Apt‐A) and a 7‐base oligonucleotide sequence (Apt‐B). In the absence of target protein, the fluorescence of FAM‐Apt‐A/Apt‐B was quenched by GO through Π‐Π stacking between GO and single‐stranded DNA. However, when thrombin was introduced into the system, a target‐induced G‐quadruplex forms with two split aptamer fragments and thrombin. The fluorescence recovered due to weak interaction between G‐quadruplex and GO. Compared to the strategy using intact aptamer, probe concentration was lowered, and an improved sensitivity was obtained. Moreover, heating process to avoid unfavorable secondary structure was avoided due to the use of shorter split aptamer fragments.
New Organic Dyes Based on Biarylmethylene‐Bridged Triphenylamine for Dye Sensitized Solar Cell
Authors: Wu Fei , Liu Haitao , Lee Lawrence Tien Lin , Chen Tao , Wang Min , Zhu Linna 
Published: May 2015

AbstractThree new organic dyes were synthesized and characterized for applications in dye‐sensitized solar cells (DSSCs). In these dyes, diarylmethylene‐bridged triphenylamine is the donor, and different acceptors and vinylthiophene are designed to get TBA‐1, TBA‐2 and TBA‐3. Their photophysical, electrochemical and photovoltaic properties were investigated, and the effects of the acceptor structures as well as the linkage on these properties were evaluated. Results demonstrated that the vinylthiophene linkage between the donor and the acceptor is favorable for improving light harvesting ability of TBA‐2. In addition, the electrochemical impedance spectroscopy experiments suggest larger Rrec and longer electron lifetime of TBA‐2. Therefore, it outperforms the other dyes, exhibiting the highest power conversion efficiency of 3.87%, with Jsc of 8.25 mA·cm−2 and Voc of 666 mV. Unfortunately, the TBA‐3 with three acceptor groups only shows efficiency of 3.52%, indicating that the design of increasing acceptor groups plays little role on enhancing the solar cell efficiency.
Synthesis and Structure of Tetrahydro‐4,7‐ethanoisobenzofuran‐1,3‐dione Derivative
Authors: Fang Mingfeng , Pan Chunmeng , Lu Song , Lin Zhongxiang , Lu Guo‐Yuan 
Published: May 2015

Abstract(1R,2R,3S,4R,7R)‐7‐Isopropyl‐6‐methylbicyclo[2.2.2]oct‐5‐ene‐2,3‐dicarboxylic acid anhydride (tetrahydro‐4,7‐ethanoisobenzofuran‐1,3‐dione derivative) adduct 2 was prepared via the isomerization of α‐pinene and β‐pinene in turpentine followed by the Diels‐Alder cycloaddition with maleic anhydride in the presence of phosphoric acid/iodine catalysis. The molecular structure of adduct 2 was characterized by IR, 1H NMR, 13C NMR, 1H‐1H COSY, DEPT, HSQC, HMBC, 2D NOESY and MS spectra. The single crystal X‐ray crystallographic analysis of adduct 2 was performed, and the X‐ray powder diffractive spectrum of the sample adduct 2 is consistent with the diffractive spectrum calculated from the single crystal data. Therefore the structure and stereochemistry of adduct 2 was established based on extensive spectral data and single crystal X‐ray analysis.
Differential Distortion of Purine Substrates by Human and Plasmodium falciparum Hypoxanthine‐Guanine Phosphoribosyltransferase to Catalyse the Formation of Mononucleotides
Authors: Karnawat Vishakha , Gogia Spriha , Balaram Hemalatha , Puranik Mrinalini 
Published: May 2015

AbstractPlasmodium falciparum (Pf) hypoxanthine‐guanine phosphoribosyltransferase (HGPRT) is a potential therapeutic target. Compared to structurally homologous human enzymes, it has expanded substrate specificity. In this study, 9‐deazapurines are used as in situ probes of the active sites of human and Pf HGPRTs. Through the use of these probes it is found that non‐covalent interactions stabilise the pre‐transition state of the HGPRT‐catalysed reaction. Vibrational spectra reveal that the bound substrates are extensively distorted, the carbonyl bond of nucleobase moiety is weakened and the substrate is destabilised along the reaction coordinate. Raman shifts of the human and Pf enzymes are used to quantify the differing degrees of hydrogen bonding in the homologues. A decreased Raman cross‐section in enzyme‐bound 9‐deazaguanine (9DAG) shows that the phenylalanine residue (Phe186 in human and Phe197 in Pf) of HGPRT stacks with the nucleobase. Differential loss of the Raman cross‐section suggests that the active site is more compact in human HGPRT as compared to the Pf enzyme, and is more so in the phosphoribosyl pyrophosphate (PRPP) complex 9DAG–PRPP–HGPRT than in 9‐deazahypoxanthine (9DAH)–PRPP–HGPRT.
Synthesis of Porous δ‐MnO2 Submicron Tubes as Highly Efficient Electrocatalyst for Rechargeable Li–O2 Batteries
Authors: Zhang Peng , Sun Dongfei , He Mu , Lang Junwei , Xu Shan , Yan Xingbin 
Published: May 2015

AbstractLithium–oxygen (Li–O2) batteries are receiving intense interest because of their high energy density. A new tubular δ‐MnO2 material prepared by a simple hydrothermal synthesis is an efficient electrocatalyst for Li–O2 batteries. The synthesized δ‐MnO2 exhibits a unique tubular structure, in which the porous walls are composed of highly dispersed ultrathin δ‐MnO2 nanosheets. Such a unique structure and its intrinsic catalytic activity provide the right electrocatalyst characteristics for high‐performance Li–O2 batteries. As a consequence, suppressed overpotentials—especially the oxygen evolution reaction overpotential—superior rate capability, and desirable cycle life are achieved with these submicron δ‐MnO2 tubes as the electrocatalyst. Remarkably, the discharge product Li2O2 of the Li–O2 battery exhibits a uniform nanosheet‐like morphology, which indicates the critical role of the δ‐MnO2 in the electrochemical process, and a mechanism is proposed to analyze the catalysis of δ‐MnO2.
Digitally‐assisted constant‐on‐time dynamic‐biasing technique for bandwidth and slew‐rate enhancement in ultra‐low‐power low‐dropout regulator
Authors: Guo Jianping , Ho Marco , Leung Ka Nang , Li Guangxiang 
Published: May 2015

SummaryA digitally‐assisted constant‐on‐time dynamic‐biasing (COT‐DB) technique has been proposed to enable significant enhancement in dynamic performances, while the average current consumption can be kept to ultralow level. This dynamic‐biasing technique has a predefined magnitude and duration on biasing current boost, which is beneficial to estimate power budget in systems with finite energy source. The proposed technique has been applied to a low‐dropout regulator (LDO) to demonstrate the effectiveness. Experimental results show that significant improvements in settling times during load‐transients and line‐transients are as much as 880×, while the current consumption is only 1.02 μA. In fact, for the same dynamic performances, the average current consumption of LDO with COT‐DB technique can be as low as 0.39% of the LDO with heavy static biasing. The digitally‐assisted implementation of the technique also allows robust augmentation of the technique onto almost all analog systems. Copyright © 2015 John Wiley & Sons, Ltd.
A load scheduler for SIP proxy servers: design, implementation and evaluation of a history weighted window approach
Authors: Montazerolghaem Ahmadreza , Shekofteh S.‐Kazem , Yaghmaee M.H. , Naghibzadeh Mahmoud 
Published: May 2015

SummaryThe widespread use of Session Initiation Protocol as a signalling protocol has created various challenges. An important one is that its throughput can be severely degraded when an overload happens in the proxy server because of several retransmissions from the user agent. One common approach to overcome this problem is ‘load balancing’. A balancer needs to know the status of proxy servers, which are continuously gathered implicitly or explicitly. Implicit methods have averagely less overhead than explicit ones. This paper attempts to prevent throughput reduction by balancing the loads among available proxy servers properly using an implicit mechanism called History Weighted Average Response time. The proposed algorithm is robust because it incurs no extra processing to proxy servers. The novelty of the mechanism is making use of ‘response time history’ to estimate the load being currently processed on servers. By implementing in a real testbed, throughput and scalability are improved compared with an important state‐of‐the‐art similar algorithm. This improvement stems from no need for modification in SIP protocol, easy implementation and application, simple computations for making decision and no need for extra feedback between servers and load balancer. Copyright © 2015 John Wiley & Sons, Ltd.
Towards power consumption in optical networks: a cognitive prediction‐based technique
Authors: Sarigiannidis Panagiotis G. , Papadimitriou Georgios , Nicopolitidis Petros , Varvarigos Emmanouel 
Published: May 2015

SummaryModern backbone, optical networks have developed into large, massive networks, which consist of numerous intermediate and terminal nodes as well as final users. These networks serve uninterruptedly multitude of users at the expense of considerable power consumption. Many research efforts are aimed at reducing energy consumption in large‐scale optical networks; however, this objective is deemed laborious: the operation of such networks has to continuously remain in good levels without disruptions. One of the most compelling techniques to remedy this situation is to switch off redundant links and devices at specific (short) periods. These links and devices remain idle as long as the network can cope with the underlying traffic demands. Hence, a power mechanism is required to manage how and when underutilized network elements may be silent during network operation. Nevertheless, this management entails fast processing and efficient decision making. While many research efforts neglect this serious factor, the problem of reducing the power consumption still threats the development of today's backbone network. In this work, an effective, cognitive power management technique is proposed by enhancing the decision making with traffic prediction. Traffic capacity is estimated in each link within the network supporting, thus, more efficient decisions on switching off underutilized or even idle network elements a priori. The technique introduced succeeds high accuracy levels, while it offers energy savings up to 30% lower than other energy‐aware schemes. Copyright © 2015 John Wiley & Sons, Ltd.
Efficient Access to 2,6,8‐Trisubstituted 4‐Aminoquinazolines through Microwave‐Assisted One‐Pot Chemoselective Tris‐Suzuki–Miyaura or SNAr/Bis‐Suzuki–Miyaura Reactions in Water
Authors: Kabri Youssef , Crozet Maxime D. , Terme Thierry , Vanelle Patrice 
Published: May 2015

AbstractAn efficient, sequential, one‐pot strategy for synthesizing polyfunctionalized quinazoline derivatives is presented. After selective amination of 6,8‐dibromo‐2,4‐dichloroquinazoline at the C‐4 position, 2,6,8‐trisubstituted 4‐aminoquinazoline derivatives were prepared through one‐pot chemoselective sequential tris‐Suzuki–Miyaura or SNAr/bis‐Suzuki–Miyaura reactions under microwave irradiation in an aqueous medium. This approach, used with a variety of boronic acids, affords polysubstituted quinazoline derivatives in good to excellent yields in only a few steps and in the environmentally benign solvent water.
Do women who succeed in male‐dominated domains help other women? The moderating role of gender identification
Authors: Kaiser Cheryl R. , Spalding Kerry E. 
Published: May 2015

AbstractIt is often expected that the first women to advance in male‐dominated fields will promote other women who follow them. Two studies test the hypothesis that some women show this expected pattern of promoting women but that others show the opposite pattern, favoring men over women. In two studies, women's gender identification moderated the extent to which they favored men over women when they advanced in a male‐dominated field. Specifically, the weaker women's gender identification, the more favoritism they showed for a male relative to a female subordinate. Gender identification did not moderate women's behavior in a context in which women were not underrepresented, pointing to the power of the situation in eliciting this relationship. Implications for the advancement of women in male‐dominated fields are discussed.
Simulation of Direct Dimethyl Ether Synthesis in a Slurry Reactor by Recirculation and Axial Dispersion Models
Authors: Zare Ghorbaei S. , Ale Ebrahim H. 
Published: May 2015

AbstractDimethyl ether is an environmentally friendly alternative to diesel fuel. This fuel can be produced directly from synthesis gas in a slurry bubble column reactor. We predicted the performance of the slurry bubble column reactor for dimethyl ether synthesis using a recirculation model and comparison with axial dispersion results. The differential equations of recirculation and axial dispersion models for the dimethyl ether synthesis are solved for a similar kinetic equation. A comparison of the results with experimental data from the literature confirms that the recirculation model better represents the reactor behavior. Finally, the effects of operating variables are studied using a simulation framework.
Experimental Study of the Spray Characteristics of Diesohol Fuel using a High‐Pressure Common‐Rail Injection System in a Diesel Engine
Authors: Song L. B. , Lin Q. Z. , Xie Y. Z. , Hu H. W. , Hu H. Q. , Pi D. , Xu S. M. 
Published: May 2015

AbstractThe spray characteristics of diesohol fuel have a direct effect on the thermal efficiency and combustion emissions performance of diesel engines. In this research, we investigated the spray characteristics of diesohol fuel under different fuel injection pressures (Pinj) in a high‐pressure common‐rail injection system and at various spray ambient pressures (Pamb) in a constant‐volume pressure vessel by using high‐speed photography technology. The research results support the concept of adding a certain percentage of ethanol to diesel, creating diesohol fuel, which can reduce the environmental impacts of vehicle emissions. Experiments on the spray characteristics were performed and the results suggested that the addition of ethanol has no significant effect on the spray tip penetration, spray cone angle, and spray tip speed. However, atomization conditions such as injection pressure and ambient pressure have a significant impact on the spray characteristics of the blended fuel.
Body Image Dissatisfaction and Eating‐Related Psychopathology in Trans Individuals: A Matched Control Study
Authors: Witcomb Gemma L. , Bouman Walter Pierre , Brewin Nicola , Richards Christina , Fernandez‐Aranda Fernando , Arcelus Jon 
Published: May 2015

AbstractHigh levels of body dissatisfaction have already been reported in the trans population; however, the root of this dissatisfaction, and its association with eating disordered behaviours, has not been studied in‐depth. This study aims to assess eating disorder risk by comparing 200 trans people, 200 people with eating disorders and 200 control participants' scores on three subscales of the Eating Disorders Inventory‐2 (EDI‐2) and to further explore dissatisfaction in the trans participants using the Hamburg Body Drawing Scale (HBDS). The results showed that overall participants with eating disorders scored higher than trans or control groups on all EDI‐2 measures, but that trans individuals had greater body dissatisfaction than control participants and, importantly, trans males had comparable body dissatisfaction scores to eating disordered males. Drive for thinness was greater in females (cis and trans) compared with males. In relation to HBDS body dissatisfaction, both trans males and trans females reported greatest dissatisfaction not only for gender‐identifying body parts but also for body shape and weight. Overall, trans males may be at particular risk for eating disordered psychopathology and other body image‐related behaviours. Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.