bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication of Ultrafine Palladium Phosphide Nanoparticles as Highly Active Catalyst for Chemoselective Hydrogenation of Alkynes
Authors: Zhao Ming 
Published: November 2015

AbstractMonodisperse palladium phosphide nanoparticles (Pd–P NPs) with a smallest size ever reported of 3.9 nm were fabricated using cheap and stable triphenylphosphine as phosphorous source. After the deposition and calcination at 300 °C and 400 °C, the resulting Pd–P NPs increased in size to 4.0 nm and 4.8 nm, respectively. Notably, the latter NPs probably crystallized with a single phase of Pd3P0.95, which acted as a highly active catalyst in semi‐ and stereoselective hydrogenation of alkynes. X‐ray photoelectron spectroscopy analysis determined a positive shift of binding energy for Pd(3d) in Pd–P NPs compared to that in Pd on carbon. It indicated the electron flow from metal to phosphorus and the larger electron deficiency of Pd in Pd–P NPs, which suppressed palladium hydride formation and subsequently increased the selectivity. Thus, this result may also indicate the applications of Pd–P and other metal–P NPs in various selective hydrogenation reactions.
A Comprehensive Study on Lyotropic Liquid–Crystalline Behavior of an Amphiphile in 20 Kinds of Amino Acid Ionic Liquids
Authors: Fujimura Kanae , Ichikawa Takahiro , Yoshio Masafumi , Kato Takashi , Ohno Hiroyuki 
Published: November 2015

AbstractWe examined the self‐organization behavior of a designed amphiphilic molecule in 20 kinds of amino acid ionic liquids composed of 1‐butyl‐3‐methylimidazolium cation and natural amino acid anion ([C4mim][AA]). Addition of [C4mim][AA], regardless of their anion species, to the amphiphile provided homogeneous mixtures showing lyotropic liquid–crystalline (LC) behavior. Upon increasing the component ratio of [C4mim][AA] in the mixtures, a successive change of the mesophase patterns from inverted hexagonal columnar, in some case via bicontinuous cubic, to layered phases was observed. By examining the LC properties at various temperatures and component ratios, we constructed lyotropic LC phase diagrams. Interestingly, the appearance of these phase diagrams is greatly different according to the selection of [AA]. Through comparison, we found that the self‐organization behavior of an amphiphile in ionic liquids can be tuned by controlling their ability to form hydrogen‐bond, van der Waals, and π‐π interactions.
Nonlinear Adaptive Control of a Hybrid Fuel Cell Power System for Electric Vehicles – a Lyapunov Stability Based Approach
Authors: Tahri Abdelouahad , El Fadil Hassan , Giri Fouad , Chaoui Fatima‐Zahra 
Published: November 2015

AbstractThis study deals with the problem of controlling hybrid storage systems in electric vehicles. The storage system includes a DC‐to‐DC switched power converter of boost type associated with a fuel‐cell generator and a buck boost converter connected to a supercapacitor. Both converters operate according to the PWM principle and the whole system model is nonlinear and subject to parameter uncertainties. The control objective is threefold: ensuring a tight dc bus voltage regulation despite the uncertainties on the fuel cell (FC) voltage–current characteristic and on the load converter; (2) guaranteeing a perfect tracking of supercapacitor (SC) current to its reference despite the SC capacitance uncertainty; ensuring asymptotic stability of the closed‐loop system. The control problem is dealt with using a nonlinear adaptive controller designed by the Lyapunov approach. It is formally shown that the proposed controller meets all its control objectives. This theoretical achievement is confirmed by several simulations.
A sensitive fluorescence method for detection of E. Coli using rhodamine 6G dyeing
Authors: Wang Yaohui , Jiang Caina , Wen Guiqing , Zhang Xinghui , Luo Yanghe , Qin Aimiao , Liang Aihui , Jiang Zhiliang 
Published: November 2015

AbstractNegatively charged bacteria combined with positively charged alkaline dye rhodamine 6G (Rh6G) in NaH2PO4–Na2HPO4 buffer solution pH 7.4, by electrostatic interaction. The dyed bacteria exhibited a strong fluorescence peak at 552 nm and fluorescence intensity was directly linear to Escherichia coli (E. coli), Bacillus subtilis (B. subtilis) and Staphylococcus aureus (S. aureus) concentrations in the range of 7.06 × 104 to 3.53 × 107, 4.95 × 105 to 2.475 × 108 and 32.5 to 16250 colony forming unit/mL (cfu/mL) respectively, with detection limits of 3.2 × 104 cfu/mL E. coli, 2.3 × 105 cfu/mL B. subtilis and 16 cfu/mL S. aureus, respectively. Samples were cultured for 12 h, after which the linear detection range for E. coli was 2 to 88 cfu/mL. This simple, rapid and sensitive method was used for the analysis of water and drinking samples. Copyright © 2015 John Wiley & Sons, Ltd.
Conformation of poly(γ‐glutamic acid) in aqueous solution
Authors: Muroga Yoshio , Nakaya Asami , Inoue Atsuki , Itoh Daiki , Abiru Masaya , Wada Kaori , Takada Masako , Ikake Hiroki , Shimizu Shigeru 
Published: November 2015

ABSTRACTLocal conformation and overall conformation of poly(γ‐DL‐glutamic acid) (PγDLGA) and poly(γ‐L‐glutamic acid) (PγLGA) in aqueous solution was studied as a function of degree of ionization ε by 1H‐NMR, circular dichroism, and potentiometric titration. It was clarified that their local conformation is represented by random coil over an entire ε range and their overall conformation is represented by expanded random‐coil in a range of ε > ε*, where ε* is about 0.3, 0.35, 0.45, and 0.5 for added‐salt concentration of 0.02M, 0.05M, 0.1M, and 0.2M, respectively. In a range of ε < ε*, however, ε dependence of their overall conformation is significantly differentiated from each other. PγDLGA tends to aggregate intramolecularly and/or intermolecularly with decreasing ε, but PγLGA still behaves as expanded random‐coil. It is speculated that spatial arrangement of adjacent carboxyl groups along the backbone chain essentially affects the overall conformation of PγGA in acidic media. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 191–198, 2016.
Interaction of cationic dodecyl‐trimethyl‐ammonium bromide with oxy‐HbGp by isothermal titration and differential scanning calorimetric studies: Effect of proximity of isoelectric point
Authors: Alves Fernanda Rosa , Carvalho Francisco Adriano O. , Carvalho José Wilson P. , Tabak Marcel 
Published: November 2015

ABSTRACTIn this work, isothermal titration and differential scanning calorimetric methods, in combination with pyrene fluorescence emission and dynamic light scattering have been used to investigate the interaction of dodecyltrimethylammonium bromide (DTAB) with the giant extracellular Glossoscolex paulistus hemoglobin (HbGp) in the oxy‐form, at pH values around the isoelectric point (pI ≈ 5.5). Our ITC results have shown that the interaction of DTAB with the hemoglobin is more intense at pH 7.0, with a smaller cac (critical aggregation concentration) value. The increase of protein concentration does not influence the cac value of the interaction, at both pH values. Therefore, the beginning of the DTAB‐oxy‐HbGp premicellar aggregates formation, in the cac region, is not affected by the increase of protein concentration. HSDSC studies show higher Tm values at pH 5.0, in the absence and presence of DTAB, when compared with pH 7.0. Furthermore, at pH 7.0, an aggregation process is observed with DTAB in the range from 0.75 to 1.5 mmol/L, noticed by the exothermic peak, and similar to that observed for pure oxy‐HbGp, at pH 5.0, and in the presence of DTAB. DLS melting curves show a decrease on the hemoglobin thermal stability for the oxy‐HbGp‐DTAB mixtures and formation of larger aggregates, at pH 7.0. Our present data, together with previous results, support the observation that the protein structural changes, at pH 7.0, occur at smaller DTAB concentrations, as compared with pH 5.0, due to the acidic pI of protein that favors the oxy‐HbGp‐cationic surfactant interaction at neutral pH. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 199–211, 2016.
A simplified process design for P450 driven hydroxylation based on surface displayed enzymes
Authors: Ströhle Frank W. , Kranen Eva , Schrader Jens , Maas Ruth , Holtmann Dirk 
Published: November 2015

ABSTRACTNew production routes for fine and bulk chemicals are important to establish further sustainable processes in industry. Besides the identification of new biocatalysts and new production routes the optimization of existing processes in regard to an improved utilization of the catalysts are needed. In this paper we describe the successful expression of P450BM3 on the surface of E. coli cells with the Autodisplay system. The successful hydroxylation of palmitic acid by using surface‐displayed P450BM3 was shown. Besides optimization of surface protein expression, several cofactor regeneration systems were compared and evaluated. Afterwards, the development of a suitable process for the biocatalytic hydroxylation of fatty acids based on the re‐use of the catalysts after a simple centrifugation was investigated. It was shown that the catalyst can be used for several times without any loss in activity. By using surface‐displayed P450s in combination with an enzymatic cofactor regeneration system a total turnover number of up to 54,700 could be reached, to the knowledge of the authors the highest value reported for a P450 monooxygenase to date. Further optimizations of the described reaction system can have an enormous impact on the process design for more sustainable bioprocesses. Biotechnol. Bioeng. 2016;113: 1225–1233. © 2015 Wiley Periodicals, Inc.
Impact of delay between imaging and treatment in patients with potentially curable pancreatic cancer
Authors: Sanjeevi S , Ivanics T , Lundell L , Kartalis N , Andrén-Sandberg Å , Blomberg J , Del Chiaro M , Ansorge C 
Published: November 2015

Abstract

Background
Locoregional pancreatic ductal adenocarcinoma (PDAC) may progress rapidly and/or disseminate despite having an early stage at diagnostic imaging. A prolonged interval from imaging to resection might represent a risk factor for encountering tumour progression at laparotomy. The aim of this study was to determine the therapeutic window for timely surgical intervention.

Methods
This observational cohort study included patients with histologically confirmed PDAC scheduled for resection with curative intent from 2008 to 2014. The impact of imaging-to-resection/reassessment (IR) interval, vascular involvement and tumour size on local tumour progression or presence of metastases at reimaging or laparotomy was evaluated using univariable and multivariable regression. Risk estimates were approximated using hazard ratios (HRs).

Results
Median IR interval was 42 days. Of 349 patients scheduled for resection, 82 had unresectable disease (resectability rate 76·5 per cent). The unresectability rate was zero when the IR interval was 22 days or shorter, and was lower for an IR interval of 32 days or less compared with longer waiting times (13 versus 26·2 per cent; HR 0·42, P = 0·021). It was also lower for tumours smaller than 30 mm than for larger tumours (13·9 versus 32·5 per cent; HR 0·34, P &lt; 0·001). Tumours with no or minor vascular involvement showed decreased rates of unresectable disease (20·6 per cent versus 38 per cent when there was major or combined vascular involvement; HR 0·43, P = 0·007). However, this failed to reach statistical significance on multivariable analysis (P = 0·411), in contrast to IR interval (P = 0·028) and tumour size (P &lt; 0·001).

Conclusion
Operation within 32 days of diagnostic imaging reduced the risk of tumour progression to unresectable disease by half compared with a longer waiting time. The results of this study highlight the importance of efficient clinical PDAC management.
Radiofrequency ablation as an alternative to hepatic resection for single small hepatocellular carcinomas
Authors: Kim G-A , Shim J H , Kim M-J , Kim S Y , Won H J , Shin Y M , Kim P N , Kim K-H , Lee S-G , Lee H C 
Published: November 2015

Abstract

Background
This study aimed to investigate whether radiofrequency ablation (RFA) is an alternative to surgical resection for hepatocellular carcinoma (HCC) within the context of current guidelines.

Methods
This retrospective study included patients with normal portal pressure and serum bilirubin level who initially underwent liver resection or RFA for a single HCC of maximum size 3 cm. Between-group differences in cumulative rates of survival and recurrence specific for HCC were analysed in the entire cohort and in a propensity score-matched cohort.

Results
A total of 604 patients were enrolled, 273 in the liver resection group and 331 in the RFA group. The 5- and 10-year HCC-specific survival rates for the resection and RFA groups were 87·6 versus 82·1 per cent and 59·0 versus 61·2 per cent respectively (P = 0·214), whereas overall 5- and 10-year recurrence-free survival rates for the corresponding groups were 60·6 versus 39·4 per cent and 37·5 versus 25·1 per cent respectively (P &lt; 0·001). In the propensity score-matched cohort (152 pairs), there were no differences in HCC-specific survival (hazard ratio (HR) 1·03 for RFAversus resection; P = 0·899), whereas recurrence-free survival again differed between the treatment groups (HR 1·75; P &lt; 0·001). RFA was independently associated with poorer outcomes in terms of treatment-site recurrence-free survival (adjusted HR 1·66; P = 0·026), but not non-treatment-site recurrence-free survival (adjusted HR 1·15; P = 0·354).

Conclusion
Although RFA carries a higher risk of treatment-site recurrence than hepatic resection, it provides comparable overall survival in patients with a single small HCC without portal hypertension or a raised bilirubin level.
Inhibition of Kallikrein‐Related Peptidases 7 and 5 by Grafting Serpin Reactive‐Center Loop Sequences onto Sunflower Trypsin Inhibitor‐1 (SFTI‐1)
Authors: Jendrny Cathleen , Beck‐Sickinger Annette G. 
Published: November 2015

AbstractSerpin proteins irreversibly inhibit serine proteases, but only a small part of the serpin reactive‐center loop (RCL) is responsible for the initial protein–protein interaction (PPI). To develop peptidic protease inhibitors, kallikrein‐related peptidases 7 (KLK7) and 5 (KLK5) were chosen. Firstly, we demonstrated that short peptides derived from RCL sequences can be cleaved by KLK7 in a substrate‐like manner. Next, these substrates were grafted onto the protease‐binding loop of sunflower trypsin inhibitor‐1 (SFTI‐1). Peptides based on kallistatin, α1‐antichymotrypsin, and protein C inhibitor (PCI) inhibited KLK7 with Ki=0.4, 0.5, and 0.7 μm, respectively. In contrast, the trypsin‐like KLK5 was only blocked by the peptide derived from PCI (Ki=0.6 μm). Thus, serpin function can be mimicked by introducing its PPI site into the rigid structure of the SFTI‐1 scaffold. This approach might be applicable not only to KLKs but also to other serine protease members, thus opening up new therapeutic fields.
Glycan‐Mediated, Ligand‐Controlled Click Chemistry for Drug‐Target Identification
Authors: Stöckmann Henning , Marin Violeta L. , Nimmer Paul , Balut Corina M. , Davidson Donald J. , Richardson Paul L. , Vasudevan Anil 
Published: November 2015

AbstractMembrane‐bound proteins are important pharmaceutical drug targets, yet few strategies exist for the identification of small‐molecule‐targeted membrane proteins in live‐cell systems. By exploiting metabolic glycan engineering of cell membrane proteins, we have developed an in situ glycan‐mediated ligand‐controlled click (“GLiCo‐Click”) chemistry methodology that enables the attachment of small‐molecule chemical probes to their receptor protein through glycans on live cells. In addition to enabling receptor enrichment from cell lysates, this strategy can be used to demonstrate target receptor engagement and enables the molecular characterization of receptors.
Recent Developments in Homogeneous Organomagnesium Catalysis
Authors: Rochat Raphaël , Lopez Michael J. , Tsurugi Hayato , Mashima Kazushi 
Published: November 2015

AbstractStoichiometric organomagnesium chemistry has continually progressed since its initiation by Victor Grignard over one century ago. Other than acting as a Lewis acid, however, homogeneous magnesium catalysis is a rare topic in the literature. Magnesium catalysts that govern reactions within the coordination sphere of magnesium have only recently begun to appear. This Concept covers recent progress in this young but potentially powerful new chapter of magnesium chemistry.
Generation of a conditional lima1a allele in zebrafish using the FLEx switch technology
Authors: Jungke Peggy , Hans Stefan , Gupta Mansi , Machate Anja , Zöller Daniela , Brand Michael 
Published: November 2015

SummaryGene trapping has emerged as a valuable tool to create conditional alleles in various model organisms. Here we report the FLEx‐based gene trap vector SAGFLEx that allows the generation of conditional mutations in zebrafish by gene‐trap mutagenesis. The SAGFLEx gene‐trap cassette comprises the rabbit β‐globin splice acceptor and the coding sequence of GFP, flanked by pairs of inversely oriented heterotypic target sites for the site‐specific recombinases Cre and Flp. Insertion of the gene‐trap cassette into endogenous genes can result in conditional mutations that are stably inverted by Cre and Flp, respectively. To test the functionality of this system we performed a pilot screen and analyzed the insertion of the gene‐trap cassette into the lima1a gene locus. In this lima1a allele, GFP expression faithfully recapitulated the endogenous lima1a expression and resulted in a complete knockout of the gene in homozygosity. Application of either Cre or Flp was able to mediate the stable inversion of the gene trap cassette and showed the ability to conditionally rescue or reintroduce the gene inactivation. Combined with pharmacologically inducible site specific recombinases the SAGFLEx vector insertions will enable precise conditional knockout studies in a spatial‐ and temporal‐controlled manner. genesis 54:19–28, 2016. © 2015 Wiley Periodicals, Inc.
Queen–worker ratio affects reproductive skew in a socially polymorphic ant
Authors: Walter Bartosz , Heinze Jürgen 
Published: November 2015

AbstractThe partitioning of reproduction among individuals in communally breeding animals varies greatly among species, from the monopolization of reproduction (high reproductive skew) to similar contribution to the offspring in others (low skew). Reproductive skew models explain how relatedness or ecological constraints affect the magnitude of reproductive skew. They typically assume that individuals are capable of flexibly reacting to social and environmental changes. Most models predict a decrease of skew when benefits of staying in the group are reduced. In the antLeptothorax acervorum, queens in colonies from marginal habitats form dominance hierarchies and only the top‐ranking queen lays eggs (“functional monogyny”). In contrast, queens in colonies from extended coniferous forests throughout the Palaearctic rarely interact aggressively and all lay eggs (“polygyny”). An experimental increase of queen:worker ratios in colonies from low‐skew populations elicits queen–queen aggression similar to that in functionally monogynous populations. Here, we show that this manipulation also results in increased reproductive inequalities among queens. Queens from natural overwintering colonies differed in the number of developing oocytes in their ovaries. These differences were greatly augmented in queens from colonies with increased queen:worker ratios relative to colonies with a low queen:worker ratio. As assumed by models of reproductive skew,L. acervorumcolonies thus appear to be capable of flexibly adjusting reproductive skew to social conditions, yet in the opposite way than predicted by most models.
Oxidative stress and life histories: unresolved issues and current needs
Authors: Speakman John R. , Blount Jonathan D. , Bronikowski Anne M. , Buffenstein Rochelle , Isaksson Caroline , Kirkwood Tom B. L. , Monaghan Pat , Ozanne Susan E. , Beaulieu Michaël , Briga Michael , Carr Sarah K. , Christensen Louise L. , Cochemé Helena M. , Cram Dominic L. , Dantzer Ben , Harper Jim M. , Jurk Diana , King Annette , Noguera Jose C. , Salin Karine , Sild Elin , Simons Mirre J. P. , Smith Shona , Stier Antoine , Tobler Michael , Vitikainen Emma , Peaker Malcolm , Selman Colin 
Published: November 2015

AbstractLife‐history theory concerns the trade‐offs that mold the patterns of investment by animals between reproduction, growth, and survival. It is widely recognized that physiology plays a role in the mediation of life‐history trade‐offs, but the details remain obscure. As life‐history theory concerns aspects of investment in the soma that influence survival, understanding the physiological basis of life histories is related, but not identical, to understanding the process of aging. One idea from the field of aging that has gained considerable traction in the area of life histories is that life‐history trade‐offs may be mediated by free radical production and oxidative stress. We outline here developments in this field and summarize a number of important unresolved issues that may guide future research efforts. The issues are as follows. First, different tissues and macromolecular targets of oxidative stress respond differently during reproduction. The functional significance of these changes, however, remains uncertain. Consequently there is a need for studies that link oxidative stress measurements to functional outcomes, such as survival. Second, measurements of oxidative stress are often highly invasive or terminal. Terminal studies of oxidative stress in wild animals, where detailed life‐history information is available, cannot generally be performed without compromising the aims of the studies that generated the life‐history data. There is a need therefore for novel non‐invasive measurements of multi‐tissue oxidative stress. Third, laboratory studies provide unrivaled opportunities for experimental manipulation but may fail to expose the physiology underpinning life‐history effects, because of the benign laboratory environment. Fourth, the idea that oxidative stress might underlie life‐history trade‐offs does not make specific enough predictions that are amenable to testing. Moreover, there is a paucity of good alternative theoretical models on which contrasting predictions might be based. Fifth, there is an enormous diversity of life‐history variation to test the idea that oxidative stress may be a key mediator. So far we have only scratched the surface. Broadening the scope may reveal new strategies linked to the processes of oxidative damage and repair. Finally, understanding the trade‐offs in life histories and understanding the process of aging are related but not identical questions. Scientists inhabiting these two spheres of activity seldom collide, yet they have much to learn from each other.