bluuebunny/crossref_metadata_2025_split huggingface dataset:
Derivatization of Antibody Fab Fragments: A Designer Enzyme for Native Protein Modification
Authors: Liebscher Sandra , Kornberger Petra , Fink Gerhard , Trost‐Gross Eva‐Maria , Höss Eva , Skerra Arne , Bordusa Frank 
Published: April 2014

AbstractBioconjugates, such as antibody–drug conjugates, have gained recent attention because of their increasing use in therapeutic and diagnostic applications. Commonly used conjugation reactions based upon chemoselective reagents exhibit a number of drawbacks: most of these reactions lack regio‐ and stereospecificity, thus resulting in loss of protein functionality due to random modifications. Enzymes provide an obvious solution to this problem, but the intrinsic (natural) substrate specificities of existing enzymes pose severe limitations to the kind of modifications that can be introduced. Here we describe the application of the novel trypsin variant trypsiligase for site‐specific modification of the C terminus of a Fab antibody fragment via a stable peptide bond. The suitability of this designed biocatalyst was demonstrated by coupling the Her2‐specific Fab to artificial functionalities of either therapeutic (PEG) or diagnostic (fluorescein) relevance. In both cases we obtained homogeneously modified Fab products bearing the artificial functionality exclusively at the desired position.
The Influence of the Precipitation/Ageing Temperature on a Cu/ZnO/ZrO2 Catalyst for Methanol Synthesis from H2 and CO2
Authors: Frei Elias , Schaadt Achim , Ludwig Thilo , Hillebrecht Harald , Krossing Ingo 
Published: April 2014

AbstractFor heterogeneous catalysts, the constitution of the precursor is an important parameter to adjust the properties of the active catalyst. Therefore, we examined the influence of the temperature during the precipitation process and during the ageing time in the mother liquor for a Cu/ZnO/ZrO2 catalyst system obtained through a coprecipitation route. The variation of the temperature affects the ratio and crystallinity of the precursor phases zincian malachite and aurichalcite, as detected by powder XRD (phase and line width) and FTIR spectroscopy (characteristic asymmetric CO stretching modes of the carbonate anions at $\tilde \nu $=1600–1100 cm−1). Therefore, the precatalyst surface area (As,BET) and pore distribution are adjustable (i.e., As,BET of 190 m2 g−1 was reached). The influence of the synthesis conditions on the catalysts activity for methanol production was analyzed and discussed up to the level of productivity/activity testing at 413/513 K and 40 bar total H2/CO2 pressure. The best catalyst showed a methanol productivity of 9.16 mmol gcat−1 h−1 (513 K, 40 bar, and gas hourly space velocity=8000) and is better than an industrial catalyst tested under the same conditions (8.34 mmol gcat−1 h−1). However, despite considerable differences in the precursor and precatalyst structure and morphology, their influence on the methanol productivity is only small. This demonstrates that the active catalyst is formed under reaction conditions.
Aqueous Sodium‐Ion Battery using a Na3V2(PO4)3 Electrode
Authors: Song Weixin , Ji Xiaobo , Zhu Yirong , Zhu Hanjun , Li Fangqian , Chen Jun , Lu Fang , Yao Yinpeng , Banks Craig. E. 
Published: April 2014

AbstractThe front cover artwork is provided by the group of Prof. Dr. Xiaobo Ji at Central South University (PR China). The image represents the electrochemical behaviors of NASICON Na3V2(PO4)3 utilized in Li+‐, Na+‐, and K+‐based aqueous electrolytes. Read the full text of the article at 10.1002/celc.201300248.
Gold‐Catalyzed Cascade Reactions of Furan‐ynes with External Nucleophiles Consisting of a 1,2‐Rearrangement: Straightforward Synthesis of Multi‐Substituted Benzo[b]furans
Authors: Sun Ning , Xie Xin , Liu Yuanhong 
Published: April 2014

AbstractA gold‐catalyzed cycloisomerization of silyl‐protected 2‐(1‐alkynyl)‐2‐alken‐1‐(2‐furanyl)‐1‐ols with various nucleophiles including water, alcohol, aniline, sulfonamide, and electron‐rich arene has been developed. The method provides a highly efficient access to 5,7‐disubstituted or 2,5,7‐trisubstituted benzo[b]furans with a wide diversity of substituents under mild reaction conditions, which are not easily available by other methods. Remarkably, an interesting rearrangement of the alkyl group from C2 to the C3 position of the furan ring takes place during the cyclization process. The following gold‐assisted allylic substitution enables an elaboration of benzo[b]furans on its side chain of the C5 position with a wide range of functional groups.
Plasmon‐Enhanced Photocurrent Generation from Click‐Chemically Modified Graphene
Authors: Yenchalwar Sandeep G. , Reddy Devarapalli Rami , Deshmukh Ashvini B. , Shelke Manjusha V. 
Published: April 2014

AbstractThe visible‐light response of Au nanoparticles (AuNPs) assembled on rGO through different molecular bridges was investigated by transient photocurrent generation. We prepared rGO with two self‐assembled monolayers (SAMs), one linear and the other with aromatic triazoles through a click cycloaddition reaction. A fivefold photocurrent enhancement was observed for triazole linkers over the aminopropyltrimethoxysilane (APTMS) linker. Cyclic voltammetry (CV) and impedance measurements also suggest fast electron transfer on account of the low resistance offered by the click‐modified rGO surface whereby introduction of triazoles offers the efficient bridge between the donor AuNPs and acceptor rGO.
Silver‐Catalyzed Formal Insertion of Arynes into RfI Bonds
Authors: Zeng Yuwen , Hu Jinbo 
Published: April 2014

AbstractAn unprecedented silver‐catalyzed formal insertion of arynes into RfI (Rf=CF3, C2F5) bonds has been developed. This protocol provides easy access to various ortho‐perfluoroalkyl iodoarenes under mild conditions. In this insertion reaction, an ionic atom‐transfer reaction of RfI occurs, and a silver‐mediated metathesis process is involved in the efficient transfer of the electropositive iodine atom.
Mechanistic and Cytotoxicity Studies of Group IV β‐Diketonate Complexes
Authors: Lord Rianne M. , Mannion James J. , Hebden Andrew J. , Nako Adi E. , Crossley Benjamin D. , McMullon Max W. , Janeway Felix D. , Phillips Roger M. , McGowan Patrick C. 
Published: April 2014

AbstractGroup IV metal complexes have previously shown promise as novel anticancer agents. Here, we discuss the mechanistic and cytotoxic nature of a series of group IV β‐diketonate coordination complexes. Clear evidence that the ligands are exchangeable on the metal centre and that the β‐diketonate ligands can act as potential drug delivery vehicles of the group IV metal ions was obtained. When evaluated for the cytotoxicity against human colon adenocarcinoma (HT‐29) and human breast adenocarcinoma (MCF‐7) cell lines, a general trend of decreasing potency down the group IV metals was observed. The most promising results obtained were for the hafnium complexes, with the tris diphenyl β‐diketonate hafnium complex exhibiting IC50 values of 4.9±0.9 μM and 3.2±0.3 μM against HT‐29 and MCF‐7, respectively, which are comparable with the activity of cisplatin against the same cell lines. This tri β‐diketonate hafnium complex is the first to show potent in vitro cytotoxic activity. The results reported show that ligand design has a significant effect on the cytotoxic potential of the complexes, and that these group IV complexes warrant further evaluation as novel metal‐containing anticancer agents.
Recipes 2.0: building for today and tomorrow
Authors: Dooley Rion , Hanlon Matthew R. 
Published: April 2014

SummaryThe history of science gateway development has, in many ways, been a story of the ‘Haves’ vs. the ‘Have‐nots’. Large infrastructure projects led the way, building thick client portals to provide coherent interfaces to an incoherent environment. Contrast this with the way the modern Web is designed using light, front end components, and outsourcing much of the heavy lifting to a mash‐up of REST application programming interfaces, and it is easy to see why modern web applications can be prototyped and refined into stable products in the time it previously took thick client portals to do an initial release. This paper argues that a ‘build for today’ philosophy can lead to the rapid development of science gateways to serve the ‘Have‐nots’. With this philosophy in mind, we are presenting Gateway DNA, a set of responsive front end components built on top of the iPlant Agave application programming interfaces. This toolkit provides the boilerplate for rapid development of lightweight science gateways using only HTML, JavaScript, and CSS. Using Gateway DNA, developers can easily stand up new gateways or quickly add new functionality to existing ones. Copyright © 2014 John Wiley & Sons, Ltd.
Excited‐State Intramolecular Proton Transfer: Photoswitching in Salicylidene Methylamine Derivatives
Authors: Jankowska Joanna , Rode Michał F. , Sadlej Joanna , Sobolewski Andrzej L. 
Published: April 2014

AbstractThe effect of chemical substitutions on the photophysical properties of the salicylidene methylamine molecule (SMA) (J. Jankowska, M. F. Rode, J. Sadlej, A. L. Sobolewski, ChemPhysChem, 2012, 13, 4287–4294) is studied with the aid of ab initio electronic structure methods. It is shown that combining π‐electron‐donating and π‐electron‐withdrawing substituents results in an electron‐density push‐and‐pull effect on the energetic landscape of the ground and the lowest excited ππ* and nπ* singlet states of the system. The presented search for the most appropriate SMA derivatives with respect to their photoswitching functionality offers an efficient prescreening tool for finding chemical structures before real synthetic realization.
Construction of Hybrid Supercapacitor–Batteries with dual‐scale shelled architecture
Authors: Qian Zhongyu , Peng Tao , Wang Jun , Qu Liangti 
Published: April 2014

AbstractPseudocapacitors bridge the gap between supercapacitors and batteries. Controllable microstructures grown on substrates have achieved success with regard to energy storage. However, traditional designs have only focused on the surface of scaffolds, which results in high specific capacitance values for the electroactive material rather than the electrodes. Inspired by slurry‐casting, a dual‐scale shell‐structured NiCo2O4 on nickel foam was assembled by using a simple and flexible solution‐based strategy. First, NiCo2O4 nanosheets covering the Ni foam skeleton surface loosely (the sample is denoted as ′pasted′) is obtained by a solution‐grown and ′dip‐and‐dry′ process (in a cobalt–nickel hydroxide solution) followed by annealing. Secondly, the NiCo2O4 nanosheets are filled in the pores of the Ni scaffold (the obtained material is denoted as ′tailored′) through chemical bath deposition process followed by annealing. The capacitance per weight of electroactive materials is not outstanding (1029 F g−1 at 10 mA cm−2), but is competitive with regard to area (3.23 F cm−2 at 10 mA cm−2). However, features in the cycling performance imply that the electrode exhibits a hybrid supercapacitor–battery behavior and that thermodynamic hysteresis promotes the ’breaking’ and ’fusing’ behavior of the material. The overall design highlights a new pathway to step out from surface to space.
Comparison of electronic volume and forward scatter principles of cell selection using flow cytometry for the evaluation of acrosome and plasma membrane integrity of bull spermatozoa
Authors: Standerholen Fride Berg , Myromslien Frøydis Deinboll , Kommisrud Elisabeth , Ropstad Erik , Waterhouse Karin Elisabeth 
Published: April 2014

AbstractThe objective of the study was to compare two different flow cytometers to reveal if there are differences between them and to find the most suitable protocol for analysis of spermatozoa. These two flow cytometers; Cell Lab Quanta™ and Coulter Epics XL, have different principles to calculate cell size, electric volume, and forward scatter (FS), respectively. Flow cytometry is a valuable tool to assess various spermatozoa quality traits simultaneously, such as plasma membrane and acrosome integrity. A double‐ and triple‐stain combination was performed to compare evaluation of these two parameters by both flow cytometers and to assess the need of a fluorescent probe to identify the spermatozoa. Propidium iodide was used to assess the proportion of dead spermatozoa, whereas Alexa Fluor® 488 conjugated peanut agglutinin (PNA‐ Alexa 488) was used to evaluate the percentage of acrosome intact and acrosome–reacted cells or degenerated cells. In the triple‐stain protocol, MitoTracker® Orange (MO) was included to test the capacity of this probe to discriminate spermatozoa from egg yolk and debris particles present in the semen sample. Cryopreserved semen from 13 Norwegian Red bulls was included in the study and the semen was evaluated immediately after thawing and after 3 hr incubation at 37°C. The results show that there is good agreement between the instruments. Nevertheless, a significant difference was found in percentages of acrosome intact live spermatozoa (% AIL) when including MO as a spermatozoa identification probe, compared to assessment without MO, with the Coulter Epics XL, while no significant difference was found when including the probe with the Cell Lab Quanta. In conclusion, the results show that cell size measurement based on electronic volume used by the Cell Lab Quanta flow cytometer is more accurate than FS used by the Coulter Epics XL flow cytometer in identification of spermatozoa. © 2014 International Society for Advancement of Cytometry
A randomized controlled trial of an Internet‐based cognitive–behavioural intervention for non‐specific chronic pain: An effectiveness and cost‐effectiveness study
Authors: de Boer M.J. , Versteegen G.J. , Vermeulen K.M. , Sanderman R. , Struys M.M.R.F. 
Published: April 2014

AbstractBackgroundCognitive–behavioural treatment can nowadays be delivered through the Internet. This form of treatment can have various advantages with regard to availability and accessibility. Previous studies showed that Internet‐based treatment for chronic pain is effective compared to waiting‐list control groups.MethodsWe conducted a randomized controlled trial comparing an Internet‐based cognitive–behavioural intervention with e‐mail therapist contact to a face‐to‐face cognitive–behavioural group intervention. Of the 72 participants who were randomly assigned to an Internet or a group course, 50 participants completed the intervention. Participants were assessed at baseline (T0), immediately after the 7‐week course (T1) and at the booster session 2 months later (T2). Pain‐related catastrophizing was the primary outcome measure. Pain intensity, fatigue, pain‐related interference, locus of control, pain coping, global health‐related quality of life and medical expenses were secondary outcome variables.ResultsSignificant improvement was found on catastrophizing, pain coping, locus of control and aspects of global health‐related quality of life in both the Internet and the group courses directly after the course and at the booster session. Pain intensity was improved in both courses at the booster session. At T2, improvement in catastrophizing, pain intensity, pain coping and some quality of life dimensions was significantly greater in completers of the Internet course than in the group course. Furthermore, the Internet course was cost‐effective compared to the group course.ConclusionsWe conclude that the Internet‐based cognitive–behavioural intervention was at least as effective as the face‐to‐face group intervention and, on some outcome measures appeared to be even more effective.
Investigation of Manganese–Iron Oxide Materials based on Manganese Ores as Oxygen Carriers for Chemical Looping with Oxygen Uncoupling (CLOU)
Authors: Mohammad Pour Nasim , Azimi Golnar , Leion Henrik , Rydén Magnus , Mattisson Tobias , Lyngfelt Anders 
Published: April 2014

AbstractOxygen carrier materials were synthesized using five different types of manganese ores with addition of iron oxide (Fe2O3), and they were investigated for their reactivity and properties in chemical looping with oxygen uncoupling (CLOU). Two different Mn/Fe molar ratios (1:2 and 2:1) were examined. The samples were manufactured by using a lab‐scale extrusion method followed by sintering at 950 °C for 4 h. To measure their reactivity, the materials were exposed to gaseous CH4 and syngas (50:50 CO/H2) as well as solid fuel (petroleum coke), in a batch fluidized‐bed reactor. With CH4, the materials based on ores from Brazil and Gabon with a Mn/Fe molar ratio 2:1 showed the best reactivity. For reduction using syngas, samples based on Eastern European and South African ores provided higher amounts of oxygen equivalent, up to 3–5 % of their mass. To investigate the ability of the samples to release gas‐phase oxygen, solid fuel experiments using 0.1 g of petroleum coke in a bed of 10 g oxygen carrier were performed at 950 °C with Brazilian, Gabon, and Eastern European ores. In these solid fuel tests samples with a Mn/Fe molar ratio of 1:2 showed higher uncoupling rates. Based on X‐ray diffraction analysis, the primary phase detected in all fresh particles was the oxidized form of MnyFe1−yOx, that is, bixbyite [(Mn,Fe)2O3]. All of the particles showed sufficiently high crushing strength (>2 N) and a reasonable attrition resistance (attrition index <6 wt % h−1). This suggests that the materials could be suitable for practical applications. It is concluded that the oxygen carriers made by manganese ores have the potential to be used as oxygen carriers for chemical‐looping combustion and chemical looping with oxygen uncoupling.
Maternal Employment During Pregnancy and Birth Outcomes: Evidence From Danish Siblings
Authors: Wüst Miriam 
Published: April 2014

SummaryI use Danish survey and administrative data to examine the impact of maternal employment during pregnancy on birth outcomes. As healthier mothers are more likely to work and health shocks to mothers may impact employment and birth outcomes, I combine two strategies: First, I control extensively for time‐varying factors that may correlate with employment and birth outcomes, such as pre‐pregnancy family income and maternal occupation, pregnancy‐related health shocks, maternal sick listing, and health behaviors (smoking and alcohol consumption). Second, to account for remaining time‐invariant heterogeneity between mothers, I compare outcomes of mothers’ consecutive children. Mothers who work during the first pregnancy trimester have a lower risk of preterm birth. I find no effect on the probability of having a baby of small size for gestational age. To rule out that health selection of mothers between pregnancies drives the results, I focus on mothers whose change in employment status is likely not to be driven by underlying health (mothers who are students in one of their pregnancies and mothers with closely spaced births). Given generous welfare benefits and strict workplace regulations in Denmark, my findings support a residual explanation, namely, that exclusion from employment may stress mothers in countries with high‐female employment rates. Copyright © 2014 John Wiley & Sons, Ltd.
Direct Constructions for General Families of Cyclic Mutually Nearly Orthogonal Latin Squares
Authors: Demirkale Fatih , Donovan Diane , Khodkar Abdollah 
Published: April 2014

AbstractTwo Latin squares and , of even order n with entries , are said to be nearly orthogonal if the superimposition of L on M yields an array in which each ordered pair , and , occurs at least once and the ordered pair occurs exactly twice. In this paper, we present direct constructions for the existence of general families of three cyclic mutually orthogonal Latin squares of orders , , and . The techniques employed are based on the principle of Methods of Differences and so we also establish infinite classes of “quasi‐difference” sets for these orders.
Analysis of the mechanisms of bioelectrochemical methane production by mixed cultures
Authors: van Eerten‐Jansen Mieke C. A. A. , Jansen Nina C. , Plugge Caroline M. , de Wilde Vinnie , Buisman Cees J. N. , ter Heijne Annemiek 
Published: April 2014

AbstractBACKGROUNDIn a methane‐producing bioelectrochemical system (BES) microorganisms grow on an electrode and catalyse the conversion of CO2 and electricity into methane. Theoretically, methane can be produced bioelectrochemically from CO2 via direct electron transfer or indirectly via hydrogen, acetate or formate. Understanding the electron transfer mechanisms could give insight into methods to steer the process towards higher rate.RESULTSIn this study, the electron transfer mechanisms of bioelectrochemical methane production by mixed cultures were investigated. At a cathode potential of −0.7 V vs. normal hydrogen electrode (NHE), average current density was 2.9 A m−2 cathode and average methane production rate was 1.8 mole e− eq m−2 cathode per day (5.2 L CH4 m−2 cathode per day). Methane was primarily produced indirectly via hydrogen and acetate. Methods to steer towards bioelectrochemical hydrogen and acetate production to further improve the performance of a methane‐producing BES are discussed.CONCLUSIONAt cathode potentials equal to or lower than −0.7 V vs. NHE and using mixed cultures, methane was primarily produced indirectly via hydrogen and acetate. (Bio)electrochemical hydrogen and acetate production rate could be increased by optimizing the cathode design and by enriching the microbial community. Consequently, the production rate of CO2‐neutral methane in a BES could be increased. © 2014 Society of Chemical Industry
An image processing pipeline to detect and segment nuclei in muscle fiber microscopic images
Authors: Guo Yanen , Xu Xiaoyin , Wang Yuanyuan , Wang Yaming , Xia Shunren , Yang Zhong 
Published: April 2014

ABSTRACTMuscle fiber images play an important role in the medical diagnosis and treatment of many muscular diseases. The number of nuclei in skeletal muscle fiber images is a key bio‐marker of the diagnosis of muscular dystrophy. In nuclei segmentation one primary challenge is to correctly separate the clustered nuclei. In this article, we developed an image processing pipeline to automatically detect, segment, and analyze nuclei in microscopic image of muscle fibers. The pipeline consists of image pre‐processing, identification of isolated nuclei, identification and segmentation of clustered nuclei, and quantitative analysis. Nuclei are initially extracted from background by using local Otsu's threshold. Based on analysis of morphological features of the isolated nuclei, including their areas, compactness, and major axis lengths, a Bayesian network is trained and applied to identify isolated nuclei from clustered nuclei and artifacts in all the images. Then a two‐step refined watershed algorithm is applied to segment clustered nuclei. After segmentation, the nuclei can be quantified for statistical analysis. Comparing the segmented results with those of manual analysis and an existing technique, we find that our proposed image processing pipeline achieves good performance with high accuracy and precision. The presented image processing pipeline can therefore help biologists increase their throughput and objectivity in analyzing large numbers of nuclei in muscle fiber images. Microsc. Res. Tech. 77:547–559, 2014. © 2014 Wiley Periodicals, Inc.