bluuebunny/crossref_metadata_2025 huggingface dataset:
Reprogramming Nonribosomal Peptide Synthetases for “Clickable” Amino Acids
Authors: Kries Hajo , Wachtel Rudolf , Pabst Anja , Wanner Benedikt , Niquille David , Hilvert Donald
Published: July 2014

Nonribosomal peptide synthetases (NRPSs) are multifunctional enzymes that produce a wide array of bioactive peptides. Here we show that a single tryptophan‐to‐serine mutation in phenylalanine‐specific NRPS adenylation domains enables the efficient activation of non‐natural aromatic amino acids functionalized with azide and alkyne groups. The resulting 105‐fold switch in substrate specificity was achieved without appreciable loss of catalytic efficiency. Moreover, the effective communication of the modified A domains with downstream modules in dipeptide synthetases permitted incorporation of O‐propargyl‐L‐tyrosine into diketopiperazines both in vitro and in vivo, even in the presence of competing phenylalanine. Because azides and alkynes readily undergo bioorthogonal click reactions, reprogramming NRPSs to accept non‐natural amino acids that contain these groups provides a potentially powerful means of isolating, labeling, and modifying biologically active peptides.
Polymerized high internal phase emulsion monoliths for the chromatographic separation of engineered nanoparticles
Authors: Hughes Jonathan M. , Budd Peter M. , Tiede Karen , Lewis John
Published: July 2014

PolyHIPEs of ethylene glycol dimethacrylate (EGDMA) and styrene/divinylbenzene were prepared by polymerization of water‐in‐oil high internal phase emulsions (HIPEs) within high pressure liquid chromatography (HPLC) columns. The columns were incorporated into a HPLC system affixed to an inductively‐coupled plasma mass spectrometer, and their potential for the separation of engineered nanoparticles was investigated. Triplicate injections of 5 and 10 nm gold particles injected onto a poly(styrene‐co‐divinylbenzene) polyHIPE column produced an average difference in retention time of 135 s. On a poly(EGDMA) column, triplicate injections of dysprosium containing polystyrene particles of 52 and 155 nm produced a difference in retention time of 8 s. In both cases the smaller particles eluted from the column first. Comparison, using scanning electron microscopy, of the polyHIPE columns after the separations, against freestanding monoliths produced from the same HIPEs, revealed no apparent change in the internal porous structure of the polyHIPEs. © 2015 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 132, 41229.
Preparation of electrospun silk fibroin nanofibers from solutions containing native silk fibrils
Authors: Liu Zhi , Zhang Feng , Ming Jinfa , Bie Shiyu , Li Junjuan , Zuo Baoqi
Published: July 2014

Electrospinning solutions containing native silk fibrils with varied diameter and length were firstly achieved by dissolving silk in CaCl2/Formic acid solvents. The structure of nanofibrils significantly improved the spinnability of electrospinning solution. The diameter of electrospun silk fibroin (SF) nanofibers increased from 40 nm to 1.8 μm, which could be achieved through increasing the solution concentration from 2 to 10%, implying a good size control over a wide range in this process. The structure of SF nanofibers transferred from random coil to beta‐sheet, before and after ethanol treatment, respectively. The mechanical properties of the SF nanofibers were improved significantly with stress and strain at break of 11.15 MPa and 7.66% in dry state, and 3.32 MPa and 174.0% in wet state. The strategy for preparing SF nanofibers with improved mechanical properties and fiber diameter control over a wide range provides benefits for the application of this material. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 41236.
Poly(N‐vinylpyrrolidone‐co‐2‐acrylamido‐2‐methylpropanesulfonate sodium): Synthesis, characterization, and its potential application for the removal of metal ions from aqueous solution
Authors: Valle Hernán , Sánchez Julio , Rivas Bernabé L.
Published: July 2014

In the current study, poly(N‐vinylpyrrolidone‐co‐2‐acrylamido‐2‐methylpropanesulfonate sodium), poly(VP‐co‐AMPS), was prepared and used for the removal of Cu2+, Cd2+, and Ni2+ ions via a polymer‐enhanced ultrafiltration (PEUF) technique. The copolymer was synthesized by radical polymerization in an aqueous medium with a comonomer feed composition of 50:50 mol %. The molecular structure of the copolymer was elucidated by ATR‐FTIR and 1H NMR spectroscopy, and the average molecular weight was obtained by GPC. The copolymer composition was determined to be 0.42 for VP and 0.58 for AMPS by 1H NMR spectroscopy. The copolymer and homopolymers exhibited different retention properties for the metal ions. PAMPS exhibited a high retention capacity for all of the metal ions at both pH values studied. PVP exhibited selectivity for nickel ions. Poly(VP‐co‐AMPS) exhibited a lower retention capacity compared to PAMPS. However, for poly(VP‐co‐AMPS), selectivity for nickel ions was observed, and the retention of copper and cadmium ions increased compared to PVP. The homopolymer mixture containing PAMPS and PVP was inefficient for the retention of the studied metal ions. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41272.
Robust Dynamic Output Feedback Guaranteed Cost Control for Discrete‐Time Systems with Time‐Varying Delays
Authors: Gyurkovics Éva , Takács Tibor
Published: July 2014

The paper proposes a dynamic output feedback guaranteed cost control for uncertain discrete‐time delay systems, where the unknown nonlinearities/uncertainties of the system are permitted to take their values in a fairly general set. The delays are considered to be unknown time varying functions with known bounds. A sufficient condition for the existence of the guaranteed cost control is given by matrix inequalities. It is shown how these inequalities can be traced back to linear matrix inequalities. An iterative algorithm is proposed to improve the quality of the control by minimizing the upper bound of the cost function. Numerical examples illustrate the effectiveness of the proposed method.
Effect of liquid hot water pretreatment severity on properties of hardwood lignin and enzymatic hydrolysis of cellulose
Authors: Ko Ja Kyong , Kim Youngmi , Ximenes Eduardo , Ladisch Michael R.
Published: July 2014

Lignin, one of the major components of lignocellulosic biomass, plays an inhibitory role on the enzymatic hydrolysis of cellulose. This work examines the role of lignin in pretreated hardwood, where extents of cellulose hydrolysis decrease, rather than increase with increasing severity of liquid hot water pretreatment. Hardwood pretreated with liquid hot water at severities ranging from log Ro = 8.25 to 12.51 resulted in 80–90% recovery of the initial lignin in the residual solids. The ratio of acid insoluble lignin (AIL) to acid soluble lignin (ASL) increased and the formation of spherical lignin droplets on the cell wall surface was observed as previously reported in the literature. When lignins were isolated from hardwoods pretreated at increasing severities and characterized based on glass transition temperature (Tg), the Tg of isolated lignins was found to increase from 171 to 180°C as the severity increased from log Ro = 10.44 to 12.51. The increase in Tg suggested that the condensation reactions of lignin molecules occurred during pretreatment and altered the lignin structure. The contribution of the changes in lignin properties to enzymatic hydrolysis were examined by carrying out Avicel hydrolysis in the presence of isolated lignins. Lignins derived from more severely pretreated hardwoods had higher Tg values and showed more pronounced inhibition of enzymatic hydrolysis. Biotechnol. Bioeng. 2015;112: 252–262. © 2014 Wiley Periodicals, Inc.
Non‐destructive label‐free continuous monitoring of in vitro chondrogenesis via electrical conductivity and its anisotropy
Authors: Oh Tong In , Kim Changhwan , Karki Bishal , Son Youngsook , Lee EunAh , Woo Eung Je
Published: July 2014

Non‐destructive label‐free continuous monitoring of in vitro tissue culture is an unmet demand in tissue engineering. Noting that different compositions of cartilage lead to different electrical tissue properties, we propose a new method to measure the electrical conductivity and its anisotropy during in vitro chondrogenesis. We used a conductivity tensor probe with 17 electrodes and a bio‐impedance spectroscopy (BIS) device to measure the conductivity values and the anisotropy ratios at the bottom and top surfaces of the tissue samples during the culture period of 6 weeks. Clearly distinguishing glycosaminoglycans (GAGs), collagen, and also various mixtures of them, the measured conductivity value and the estimated tissue anisotropy provide diagnostic information of the depth‐dependent tissue structure and compositions. Continuously monitoring the individual tissue during the entire chondrogenesis process without any adverse effect, the proposed method may significantly increase the productivity of cartilage tissue engineering. Biotechnol. Bioeng. 2015;112: 422–427. © 2014 Wiley Periodicals, Inc.
Does biopolymers composition in seeds contribute to the flax resistance against the Fusarium infection?
Authors: Zeitoun Ahmed M. , Preisner Marta , Kulma Anna , Dymińska Lucyna , Hanuza Jerzy , Starzycki Michal , Szopa Jan
Published: July 2014

Over the last decades, the cultivation of fibrous flax declined heavily. There are number of reasons for that fact; one of them is flax susceptibility to the pathogen infection. Damages caused mainly by fungi from genus Fusarium lead to the significant losses when cultivating flax, which in turn discourage farmers to grow flax. Therefore, to launch the new products from flax with attractive properties there is a need to obtain new flax varieties with increased resistance to pathogens. In order to obtain the better quality of flax fiber, we previously generated flax with reduced pectin or lignin level (cell wall polymers). The modifications altered also plants' resistance to the Fusarium infection. Undoubtedly, the plant defense system is complex, however, in this article we aimed to investigate the composition of modified flax seeds and to correlate it with the observed changes in the flax resistance to the pathogen attack. In particular, we evaluated the content and composition of carbohydrates (cell wall polymers: pectin, cellulose, hemicelluloses and mucilage), and phenylpropanoid compounds (lignin, lignans, phenolics). From the obtained results we concluded that the observed changes in the vulnerability to pathogens putatively correlate with the antioxidant potential of phenylpropanoids accumulated in seeds, seco‐isolariciresinol and coumaric acid diglycosides in particular, and with pectin level as a carbon source for pathogens. Surprisingly, relatively less important for the resistance was the physical barrier, including lignin and cellulose amount and cellulose structure. Certainly, the hypothesis should be verified on a larger number of genotypes. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:992–1004, 2014
An Operando FTIR Spectroscopic and Kinetic Study of Carbon Monoxide Pressure Influence on Rhodium‐Catalyzed Olefin Hydroformylation
Authors: Kubis Christoph , Sawall Mathias , Block Axel , Neymeyr Klaus , Ludwig Ralf , Börner Armin , Selent Detlef
Published: July 2014

The influence of carbon monoxide concentration on the kinetics of the hydroformylation of 3,3‐dimethyl‐1‐butene with a phosphite‐modified rhodium catalyst has been studied for the pressure range p(CO)=0.20–3.83 MPa. Highly resolved time‐dependent concentration profiles of the organometallic intermediates were derived from IR spectroscopic data collected in situ for the entire olefin‐conversion range. The dynamics of the catalyst and organic components are described by enzyme‐type kinetics with competitive and uncompetitive inhibition reactions involving carbon monoxide taken into account. Saturation of the alkyl–rhodium intermediates with carbon monoxide as a cosubstrate occurs between 1.5 and 2 MPa of carbon monoxide pressure, which brings about a convergence of aldehyde regioselectivity. Hydrogenolysis of the acyl intermediate is fast at 30 °C and low pressure of p(CO)=0.2 MPa, but is of minus first order with respect to the solution concentration of carbon monoxide. Resting 18‐electron hydrido and acyl complexes that correspond to early and late rate‐determining states, respectively, coexist as long as the conversion of the substrate is not complete.
Complex‐Formation‐Enhanced Fluorescence Quenching Effect for Efficient Detection of Picric Acid
Authors: Ding Aixiang , Yang Longmei , Zhang Yuyang , Zhang Gaobin , Kong Lin , Zhang Xuanjun , Tian Yupeng , Tao Xutang , Yang Jiaxiang
Published: July 2014

Amine‐functionalized α‐cyanostilbene derivatives (Z)‐2‐(4‐aminophenyl)‐3‐(4‐butoxyphenyl)acrylonitrile (ABA) and (Z)‐3‐(4‐butoxyphenyl)‐2‐[4‐(butylamino)phenyl]acrylonitrile (BBA) were designed for specific recognition of picric acid (PA), an environmental and biological pollutant. The 1:1 host–guest complexes formed between the chemosensors and PA enhanced fluorescence quenching, thus leading to sensitive and selective detection in aqueous media and the solid phase.
A Molecular Placeholder Strategy To Access a Family of Transition‐Metal‐Functionalized Vanadium Oxide Clusters
Authors: Kastner Katharina , Margraf Johannes T. , Clark Timothy , Streb Carsten
Published: July 2014

Systematic access to metal‐functionalized polyoxometalates has thus far been limited to lacunary tungsten oxide and molybdenum oxide clusters. The first controlled, stepwise bottom‐up assembly route to metal‐functionalized molecular vanadium oxides is now presented. A di‐vacant vanadate cluster with two metal binding sites, (DMA)2[V12O32Cl]3− (DMA=dimethylammonium) is formed spontaneously in solution and characterized by single‐crystal X‐ray diffraction, ESI mass spectrometry, 51V NMR spectroscopy, and elemental analyses. In the cluster, the metal binding sites are selectively blocked by hydrogen‐bonded DMA placeholder cations. Reaction of the cluster with transition metals TM (Fe3+, Co2+, Cu2+, Zn2+) gives access to mono‐functionalized vanadate clusters (DMA)[{TM(L)}V12O32Cl]n− (L=ligand). Metal binding is accomplished by significant distortions of the vanadium oxide framework reminiscent of a pincer movement. Cluster stability under technologically relevant conditions in the solid‐state and solution is demonstrated.
Kinetic Resolution of Profens by EnantioselectiveEsterification Catalyzed by Candida antarctica and Candida rugosa Lipases
Authors: Sikora Adam , Siódmiak Tomasz , Marszałł Michał Piotr
Published: July 2014

Profens (2‐arylpropionic acids) are known as one of the major nonsteroidal antiinflammatory drugs (NSAIDs) used in the treatment of inflammation associated with tissue injury. The inflammatory activity of profens is mainly due to their (S)‐enantiomer, whereas they are commercially available not only as pure enantiomers, but as racemates as well. There are several methods widely used in order to obtain enantiomerically pure compounds, however, the kinetic resolution with the application of lipases as biocatalysts may have an added advantage in the production of optically pure active pharmaceutical ingredients, such as milder reaction conditions, reduced energy requirements, and production costs. The aim of this study was to compare the results described in the literature in the case of the influence of reaction medium, alcohol moiety, and reaction temperature on the catalytic activity of lipases from Candida antarctica and Candida rugosa. Chirality 26:663–669, 2014. © 2014 Wiley Periodicals, Inc.
Survival analysis of Hispanics in a cohort of patients with hepatocellular carcinoma
Authors: Aparo Santiago , Goel Sanjay , Lin Daniel , Ohri Nitin , Schwartz Jonathan M. , Lo Yungtai , Kaubisch Andreas
Published: July 2014

Background

Hepatocellular carcinoma (HCC) appears to have worse prognosis among Hispanics and other ethnic minorities in the United States. We investigated the overall survival (OS) of Hispanics with HCC and compared it with non‐Hispanic (NH) whites and NH blacks.

Methods

Patients diagnosed and treated for HCC at an urban medical center between 2000 and 2011 were identified from the institutional cancer registry. A Cox proportional‐hazard model was used to assess survival differences between Hispanics, NH whites, and NH blacks after adjusting for clinically and statistically significant variables.

Results

A total of 681 patients were identified, 24 of whom were excluded due to inability to confirm the diagnosis of HCC based on radiologic criteria and 24 due to unavailable ethnicity data. The remaining 633 patients were used for analysis. Of this final cohort, 49% (n = 309) were Hispanic, 23% (n = 144) were NH white, and 28% (n = 180) were NH black. The median OS among Hispanics was 16.3 months and was similar to that of NH whites (14.0 months) and NH blacks (17.3 months) (P = 0.76). Multivariate analysis revealed a hazard ratio for death for Hispanics of 0.78 (95% confidence interval 0.58‐1.07, P = .12) when compared with NH whites and a hazard ratio for death of 0.89 (95% confidence interval 0.68‐1.19, P = 0.46) when compared with NH blacks.

Conclusions

In contrast to previous reports, Hispanics with HCC from this cohort experienced similar OS when compared with NH whites and NH blacks. Cancer 2014;120:3683–3690. © 2014 American Cancer Society.
Cascade Reactions Catalyzed by Metal Organic Frameworks
Authors: Dhakshinamoorthy Amarajothi , Garcia Hermenegildo
Published: July 2014

Cascade or tandem reactions where two or more individual reactions are carried out in one pot constitute a clear example of process intensification, targeting the maximization of spatial and temporal productivity with mobilization of minimum resources. In the case of catalytic reactions, cascade processes require bi‐/multifunctional catalysts that contain different classes of active sites. Herein, we show that the features and properties of metal–organic frameworks (MOFs) make these solids very appropriate materials for the development of catalysts for cascade reactions. Due to composition and structure, MOFs can incorporate different types of sites at the metal nodes, organic linkers, or at the empty internal pores, allowing the flexible design and synthesis of multifunctional catalysts. After some introductory sections on the relevance of cascade reactions from the point of view of competitiveness, sustainability, and environmental friendliness, the main part of the text provides a comprehensive review of the literature reporting the use of MOFs as heterogeneous catalysts for cascade reactions including those that combine in different ways acid/base, oxidation/reduction, and metal–organic centers. The final section summarizes the current state of the art, indicating that the development of a first commercial synthesis of a high‐added‐value fine chemical will be a crucial milestone in this area.
The use of dried blood spots for quantification of 15 antipsychotics and 7 metabolites with ultra‐high performance liquid chromatography ‐ tandem mass spectrometry
Authors: Patteet Lisbeth , Maudens Kristof E. , Stove Christophe P. , Lambert Willy E. , Morrens Manuel , Sabbe Bernard , Neels Hugo
Published: July 2014

Therapeutic drug monitoring of antipsychotics is important in optimizing individual therapy. In psychiatric populations, classical venous blood sampling is experienced as frightening. Interest in alternative techniques, like dried blood spots (DBS), has consequently increased. A fast and easy to perform DBS method for quantification of 16 antipsychotics (amisulpride, aripiprazole, asenapine, bromperidol, clozapine, haloperidol, iloperidone, levosulpiride, lurasidone, olanzapine, paliperidone, pipamperone, quetiapine, risperidone, sertindole and zuclopenthixol) and 8 metabolites was developed. DBS were prepared using 25 μL of whole blood and extraction of complete spots was performed using methanol: methyl‐t‐butyl‐ether (4:1). After evaporation, the extract was reconstituted in the mobile phase and 10 μL were injected on an ultra‐high performance liquid chromatography‐tandem mass spectrometry (UHPLC‐MS/MS). Separation using a C18 column and gradient elution with a flow rate of 0.5 mL/min resulted in a 6‐min run‐time. Ionization was performed in positive mode and a dynamic MRM method was applied. Median recovery was 66.4 % (range 28.7‐84.5%). Accuracy was within the acceptance criteria, except for pipamperone (LLOQ and low concentration) and lurasidone (low concentration). Imprecision was only aberrant for lurasidone at low and medium concentration. All compounds were stable during 1 month at room temperature, 4 °C and −18 °C. Lurasidone was unstable when the extract was stored for 12 h on the autosampler. Absolute matrix effects (ME) (median 66.1%) were compensated by the use of deuterated IS (median 98.8%). The DBS method was successfully applied on 25‐μL capillary DBS from patients and proved to be a reliable alternative for quantification of all antipsychotics except for olanzapine and N‐desmethylolanzapine. Copyright © 2014 John Wiley & Sons, Ltd.
Above‐ and belowground herbivory jointly impact defense and seed dispersal traits in Taraxacum officinale
Authors: de la Peña Eduardo , Bonte Dries
Published: July 2014

Plants are able to cope with herbivores by inducing defensive traits or growth responses that allow them to reduce or avoid the impact of herbivores. Since above‐ and belowground herbivores differ substantially in life‐history traits, for example feeding types, and their spatial distribution, it is likely that they induce different responses in plants. Moreover, strong interactive effects on defense and plant growth are expected when above‐ and belowground herbivores are jointly present. The strengths and directions of these responses have been scarcely addressed in the literature. Using Taraxacum officinale, the root‐feeding nematode Meloidogyne hapla and the locust Schistocerca gregaria as a model species, we examined to what degree above‐ and belowground herbivory affect (1) plant growth responses, (2) the induction of plant defensive traits, that is, leaf trichomes, and (3) changes in dispersal‐related seed traits and seed germination. We compared the performance of plants originating from different populations to address whether plant responses are conserved across putative different genotypes. Overall, aboveground herbivory resulted in increased plant biomass. Root herbivory had no effect on plant growth. Plants exposed to the two herbivores showed fewer leaf trichomes than plants challenged only by one herbivore and consequently experienced greater aboveground herbivory. In addition, herbivory had effects that reached beyond the individual plant by modifying seed morphology, producing seeds with longer pappus, and germination success.
ChineseMNCs’ Preparation for Host‐Country Labor Relations: An Exploration of Country‐of‐Origin Effect
Authors: Zhu Judith Shuqin , Zhu Cherrie Jiuhua , De Cieri Helen
Published: July 2014

Numerous studies have demonstrated the existence of the country‐of‐origin effect and how this effect interacts with other factors in shaping multinational corporations’ (MNCs’) practices. However, there has been little investigation of different forms of country‐of‐origin effect, the mechanisms through which this effect occurs, or country‐of‐origin effect onMNCsfrom emerging markets. This study explores how country‐of‐origin effect manifests in ChineseMNCs’ preparation for managing host country labor relations, an important area of human resource management (HRM). Based on a study of 21 ChineseMNCs, we argue that country‐of‐origin effect in relation to ChineseMNCsmainly manifests in two implicit forms, including transfer of management ethos and competitive disadvantage generated from the home base, rather than in the form of direct practice transfer as commonly suggested in the current literature. The major mechanism through which country‐of‐origin effect plays out is the mind‐set of managers, rather than formally established corporate control instruments. © 2014 Wiley Periodicals, Inc.
Sources and transport of nitrate constrained by the isotopic technique in a karst catchment: an example from Southwest China
Authors: Yue Fu‐Jun , Li Si‐Liang , Liu Cong‐Qiang , Lang Yun‐Chao , Ding Hu
Published: July 2014

The concentration and isotopic composition of nitrate were analyzed to improve an understanding of nitrate sources and transformation processes in a typical karstic agricultural field in the Houzhai catchment, Guizhou Province, Southwest China. The results revealed that no distinct spatial pattern of content and isotopic composition of nitrate exists in this karst catchment. Nitrate in surface stream (SFS) had slightly lighter isotopic composition and lower concentration compared with nitrate in subterranean stream (STS) during the dry season. Concentrations of SFS nitrate increased to concentrations similar to those of STS during the wet season. The isotopic values indicated that nitrate were mainly impacted by manure sources during the dry season and influenced by a mix of chemical fertilizer and manure during the wet season. The denitrification rates were roughly estimated based on the isotopic compositions of nitrate after considering volatilization and ignoring assimilation. The calculated result showed that approximately one fifth of nitrate load was removed by denitrification in the catchment. Annual nitrate flux from the outlets accounted for 14.2% of applied total fertilizers used in the catchment, approximately 85% of total transported flux from the catchment in the wet season. Furthermore, chemical weathering processes were enhanced by using nitrogen fertilizer because liberated protons and enhanced HCO3− flux were produced through by nitrification. Copyright © 2014 John Wiley & Sons, Ltd.
Biomolecular Structure and Dynamics with Neutrons: The View from Simulation
Authors: Hong Liang , Petridis Loukas , Smith Jeremy C.
Published: July 2014

The characterization of the structure and internal dynamics of biomolecules is essential to understanding their biological function. Neutron scattering probes similar time‐ and length‐scales to molecular dynamics simulation. Hence, simulation models of biomolecules have become invaluable in the interpretation of experimental neutron data. Here, we report on advances in the application of simulation in developing neutron scattering to investigate internal protein motions and, as an example of industrial relevance, in the derivation of physical models of use in biofuel renewable energy research.
SEQUENTIAL MONTE CARLO SAMPLING FOR DSGE MODELS
Authors: Herbst Edward , Schorfheide Frank
Published: July 2014

We develop a sequential Monte Carlo (SMC) algorithm for estimating Bayesian dynamic stochastic general equilibrium (DSGE) models; wherein a particle approximation to the posterior is built iteratively through tempering the likelihood. Using two empirical illustrations consisting of the Smets and Wouters model and a larger news shock model we show that the SMC algorithm is better suited for multimodal and irregular posterior distributions than the widely used random walk Metropolis–Hastings algorithm. We find that a more diffuse prior for the Smets and Wouters model improves its marginal data density and that a slight modification of the prior for the news shock model leads to drastic changes in the posterior inference about the importance of news shocks for fluctuations in hours worked. Unlike standard Markov chain Monte Carlo (MCMC) techniques; the SMC algorithm is well suited for parallel computing. Copyright © 2014 John Wiley & Sons, Ltd.
SDF-1/CXCR4 Axis in Tie2-Lineage Cells Including Endothelial Progenitor Cells Contributes to Bone Fracture Healing
Authors: Kawakami Yohei , Ii Masaaki , Matsumoto Tomoyuki , Kuroda Ryosuke , Kuroda Tomoya , Kwon Sang-Mo , Kawamoto Atsuhiko , Akimaru Hiroshi , Mifune Yutaka , Shoji Taro , Fukui Tomoaki , Kurosaka Masahiro , Asahara Takayuki
Published: July 2014

CXC chemokine receptor 4 (CXCR4) is a specific receptor for stromal-derived-factor 1 (SDF-1). SDF-1/CXCR4 interaction is reported to play an important role in vascular development. On the other hand, the therapeutic potential of endothelial progenitor cells (EPCs) in fracture healing has been demonstrated with mechanistic insight of vasculogenesis/angiogenesis and osteogenesis enhancement at sites of fracture. The purpose of this study was to investigate the influence of the SDF-1/CXCR4 pathway in Tie2-lineage cells (including EPCs) in bone formation. We created CXCR4 gene conditional knockout mice using the Cre/loxP system and set two groups of mice: Tie2-CreER CXCR4 knockout mice (CXCR4−/−) and wild-type mice (WT). We report here that in vitro, EPCs derived from of CXCR4−/− mouse bone marrow demonstrated severe reduction of migration activity and EPC colony-forming activity when compared with those derived from WT mouse bone marrow. In vivo, radiological and morphological examinations showed fracture healing delayed in the CXCR4−/− group and the relative callus area at weeks 2 and 3 was significantly smaller in CXCR4−/− group mice. Quantitative analysis of capillary density at perifracture sites also showed a significant decrease in the CXCR4−/− group. Especially, CXCR4−/−group mice demonstrated significant early reduction of blood flow recovery at fracture sites compared with the WT group in laser Doppler perfusion imaging analysis. Real-time RT-PCR analysis showed that the gene expressions of angiogenic markers (CD31, VE-cadherin, vascular endothelial growth factor [VEGF]) and osteogenic markers (osteocalcin, collagen 1A1, bone morphogenetic protein 2 [BMP2]) were lower in the CXCR4−/− group. In the gain-of-function study, the fracture in the SDF-1 intraperitoneally injected WT group healed significantly faster with enough callus formation compared with the SDF-1 injected CXCR4−/− group. We demonstrated that an EPC SDF-1/CXCR4 axis plays an important role in bone fracture healing using Tie2-CreER CXCR4 conditional knockout mice. © 2014 American Society for Bone and Mineral Research.
A New Method of Dimroth Rearrangement in Fused Triazolo[1,5‐d]‐1,2,4‐triazine
Authors: Ezema B. E. , Akpanisi L. E. S. , Ezema C. G. , Onoabedje A. E.
Published: July 2014

Ethyl 7‐(2‐ethoxy‐2‐oxoethyl)‐3‐phenyl‐[1–3]triazolo[5,1‐c][1,2,4]triazine‐6‐carboxylate (the parent compound) was synthesized by reaction of 4‐phenyl–1H‐1,2,3‐triazole‐5‐diazonium chloride with diethyl‐2‐oxopropane‐1,3‐dicarboxylate at cooling for 2 h. During the reaction of the parent compound with p‐toluenesulphonyl azide in triethylamine, the Dimroth rearrangement occurred to give the tricyclic compound.
Postconditioning mitigates cell death following oxygen and glucose deprivation in PC12 cells and forebrain reperfusion injury in rats
Authors: Lin Han‐Chen , Narasimhan Purnima , Liu Shin‐Yun , Chan Pak H. , Lai I‐Rue
Published: July 2014

Postconditioning mitigates ischemia‐induced cellular damage via a modified reperfusion procedure. Mitochondrial permeability transition (MPT) is an important pathophysiological change in reperfusion injury. This study explores the role of MPT modulation underlying hypoxic postconditioning (HPoC) in PC12 cells and studies the neuroprotective effects of ischemic postconditioning (IPoC) on rats. Oxygen‐glucose deprivation (OGD) was performed for 10 hr on PC12 cells. HPoC was induced by three cycles of 10‐min reoxygenation/10‐min rehypoxia after OGD. The MPT inhibitor N‐methyl‐4‐isoleucine cyclosporine (NIM811) and the MPT inducer carboxyatractyloside (CATR) were administered to selective groups before OGD. Cellular death was evaluated by flow cytometry and Western blot analysis. JC‐1 fluorescence signal was used to estimate the mitochondrial membrane potential (△Ψm). Transient global cerebral ischemia (tGCI) was induced via the two‐vessel occlusion and hypotension method in male Sprague Dawley rats. IPoC was induced by three cycles of 10‐sec reperfusion/10‐sec reocclusion after index ischemia. HPoC and NIM811 administration attenuated cell death, cytochrome c release, and caspase‐3 activity and maintained △Ψm of PC12 cells after OGD. The addition of CATR negated the protection conferred by HPoC. IPoC reduced neuronal degeneration and cytochrome c release and cleaved caspase‐9 expression of hippocampal CA1 neurons in rats after tGCI. HPoC protected PC12 cells against OGD by modulating the MPT. IPoC attenuated degeneration of hippocampal neurons after cerebral ischemia. © 2014 Wiley Periodicals, Inc.
Gas chromatographic determination of some phenolic compounds in fuels and engine oil after simultaneous derivatization and microextraction
Authors: Farajzadeh Mir Ali , Yadeghari Adeleh , Khoshmaram Leila , Ghorbanpour Houshang
Published: July 2014

In this study, a simultaneous derivatization/air‐assisted liquid–liquid microextraction method has been developed for sample preparation of some phenolic compounds in fuels and engine oil. Analytes are transferred by back liquid–liquid extraction into NaOH solution and then are derivatized with butyl chloroformate and extracted simultaneously into carbon tetrachloride. The extracted derivatized analytes are analyzed using gas chromatography with flame ionization detection. The effect of extracting solvent type, derivatization agent and extraction solvent volumes, ionic strength of the aqueous solution, number of extraction cycles, etc., on the extraction efficiency is investigated. The calibration graphs are linear in the range of 3–10 000 μg/L. Enhancement factors, enrichment factors, and extraction recoveries are in the ranges of 497 to 1471, 571 to 991, and 60 to 109%, respectively. Detection limits are obtained in the range of 0.8 to 2.0 μg/L. Relative standard deviations for the extraction of each selected phenols are in the ranges of 2–4% for intraday (n = 6) and 3–6% (n = 5) for interday precisions for 200 μg/L. This technique is successfully applied for the extraction, preconcentration, and determination of the selected phenols in gasoline, kerosene, gas oil, and engine oil.
Photoluminescent Nematic Liquid Crystalline Elastomer with a Thermomechanical Emission Variation Function
Authors: Wei Renbo , He Yaning , Wang Xiaogong , Keller Patrick
Published: July 2014

Nematic liquid crystalline elastomer (LCE) microactuators are developed, showing simultaneous thermomechanical deformation and photoluminescence (PL) emission variation functions. The microactuators are prepared by a method combining soft‐lithography and photo‐polymerization/crosslinking. 1,4‐Bis(α‐cyano‐4‐methoxystyryl)benzene as the PL dye is synthesized, characterized, and introduced into LCEs as a dopant in the preparation process. During the heating process, PL emission of the LCE micropillars under blue light excitation becomes significantly weak when the micropillars contract. When cooling down, the emission completely recovers as the micropillars stretches back to their original shape. The PL intensity variation at the transition is proved to be related to the thermomechanical deformation.

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Do Parkinson's Disease Patients Have Deficits in Sequential Sampling Tasks?
Authors: Djamshidian Atbin , Mulhall Jennifer , Tomassini Alessandro , Crotty Grace , Warner Thomas T. , Lees Andrew , O'Sullivan Sean S. , Averbeck Bruno B.
Published: July 2014

The aim of this study was to assess the neuropsychological behavior of Parkinson's disease (PD) patients with addictive behaviors. Characteristically, these patients have younger onset of PD, higher novelty‐seeking personality traits, jump to conclusions, and often make irrational choices. We assessed whether PD patients with and without addictive behaviors have deficits in a sequential sampling task, often called the secretary problem. In this task, participants needed to pick the best out of multiple offers. Critically, once participants rejected a deal, this option became unavailable. Thus, decisions needed to be balanced not to stop too soon or sample for too long and miss the best deal. We tested 13 PD patients with and 13 patients without addictive behaviors. Results were compared to healthy volunteers. We found that all patients declined fewer options before committing to a deal. There was, however, no difference between the two patient groups. Furthermore, there was no difference in overall choice rank between patients and controls. These results suggest that, compared to controls, PD patients gather less evidence before committing to an offer, but have no deficits in recognizing the best deal out of many options, regardless of whether or not they have addictive behaviors.
Characteristics and temporal trends in patient registries: focus on the life sciences industry, 1981–2012
Authors: Travers Karin , Sallum Rachel H. , Burns Meghan D. , Barr Charles E. , Beattie Mary S. , Pashos Chris L. , Luce Bryan R.
Published: July 2014

Purpose

Patient registries are used to monitor safety, examine real‐world effectiveness, and may potentially contribute to comparative effectiveness research. To our knowledge, life sciences industry (LSI)‐sponsored registries have not been systematically categorized. This study represents a first step toward understanding such registries over time.

Methods

Studies described as registries were identified in the ClinicalTrials.gov database. Characteristics from these registry records were abstracted and analyzed.

Results

Of 1202 registries identified, approximately 47% reported LSI sponsorship. These 562 LSI registries varied in focus: medical devices (n = 193, 34%), specific drugs (n = 173, 31%), procedures (n = 29, 5%), or particular diseases (n = 139, 25%). Thirty‐three registries (<6%) evaluated pregnancy outcomes. The most common therapeutic area was cardiovascular (n = 234, 42%); others included endocrinology, immunology, oncology, musculoskeletal disorders, and neurology. The two most often measured outcomes were clinical effectiveness and safety, each of which appeared in 363/562 (65%) of LSI registries. Other outcomes included real‐world clinical practice patterns (n = 122, 22%), patient‐reported outcomes (n = 106, 19%), disease epidemiology/natural history (n = 69, 12%), and economic outcomes (n = 30, 5%). The number of LSI registries and their geographic diversity has increased over time.

Conclusions

The LSI registries represent a substantial proportion of all patient registries documented in ClinicalTrials.gov. These prospective studies are growing in number and encompass diverse therapeutic areas and geographic regions. Most registries measure multiple outcomes and capture real‐world data that may be unavailable through other study designs. This classification of LSI registries documents their use for studying heterogeneity of diseases, examining treatment patterns, measuring patient‐reported outcomes, examining economic outcomes, and performing comparative effectiveness research. © 2014 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd.
The prevalence and implications of elderly inpatients' desire for a formal psychological help at the start of cancer treatment
Authors: Dubruille Stéphanie , Libert Yves , Merckaert Isabelle , Reynaert Christine , Vandenbossche Sandrine , Roos Myriam , Bron Dominique , Razavi Darius
Published: July 2014

Introduction

Little is known about elderly cancer inpatients' desire for psychological help.

Purpose

The aim of this study was to investigate whether elderly cancer inpatients well informed about their diagnosis expressed a desire to receive formal psychological help at the start of their cancer treatment. The characteristics of the patients that sought help were examined.

Methods

This cross‐sectional study assessed 650 consecutive cancer inpatients that were 65 years of age and older when they started treatment for breast, colorectal, ovarian, lung, prostate or haematological cancers. Disease‐related, medical and psychological characteristics of these patients were assessed using validated tools.

Results

Distress and cognitive impairment were experienced by 37% and 46% of elderly cancer inpatients, respectively. However, only 12% of patients reported a desire for formal psychological help (14% of women vs 9% of men). The patient characteristics examined were found to be weakly associated with this desire (this explained 16% of the variance for women and 14% for men). For the female subgroup, this desire was associated with age [<75 years vs ≥75 years; odds ratio (OR) = 2.57], marital status (without a partner vs with a partner; OR = 2.26) and distress (OR = 1.13). For the male subgroup, loss of functional autonomy (OR = 1.41) and pain (OR = 1.22) were relevant characteristics.

Conclusions

Although more than about four out of 10 elderly cancer inpatients in this study experience distress or cognitive impairment, only about one out of 10 expresses a desire for formal psychological help. Therefore, an appropriate sequence of interventions should be scheduled in order to offer them an optimal formal psychological help. Copyright © 2014 John Wiley & Sons, Ltd.
The characteristics and effectiveness of Question Prompt List interventions in oncology: a systematic review of the literature
Authors: Brandes Kim , Linn Annemiek J. , Butow Phyllis N. , van Weert Julia C. M.
Published: July 2014

Objective

Question Prompt Lists (QPLs) have been used extensively in the oncology setting to improve communication, psychological and/or cognitive outcomes. In this systematic review, the objectives were to (a) examine the methodological quality of QPL interventions, (b) review the effectiveness of QPL interventions on communication, psychological and/or cognitive outcomes of cancer patients, (c) gain more insight into the characteristics of QPL interventions (e.g., the number and content of questions, and the mode of delivery) and (d) explore whether the effectiveness of QPL interventions might be explained by their characteristics.

Method

A systematic literature search was conducted in PsycINFO, Medline, CINAHL and CENTRAL. Empirical studies that investigated the use and effectiveness of QPL interventions in an oncology setting were included. The methodological quality of the included studies was assessed using the Cochrane method.

Results

Sixteen articles met the inclusion criteria. Results indicated evidence for the effectiveness of QPL interventions in enhancing patient participation (i.e., question asking). Furthermore, there was evidence that QPL interventions can influence psychological outcomes (i.e., anxiety at follow‐up) and cognitive outcomes (i.e., recall of information). The majority of QPL interventions were given to patients before their consultation in hardcopy. In most studies, QPLs were combined with other intervention components. It is suggested that characteristics of a QPL intervention (i.e., the number of questions on a QPL and provider training) can influence its effectiveness.

Conclusion

Question Prompt List interventions are effective in improving communication, psychological and cognitive outcomes of cancer patients. Copyright © 2014 John Wiley & Sons, Ltd.
Water‐Soluble Monolayer Molybdenum Disulfide Quantum Dots with Upconversion Fluorescence
Authors: Huang Hao , Du Cuicui , Shi Hongyan , Feng Xun , Li Jin , Tan Yanlei , Song Wenbo
Published: July 2014

Uniform water‐soluble monolayer MoS2 quantum dots (MQDs) with lateral sizes of ≈2.1 nm, a clearly zigzag‐terminated edge, and a hexagonal lattice structure are achieved using ammonium molybdate, thiourea, and N‐acetyl‐l‐cysteine (NAC) as precursors and the capping reagent in a facile one‐pot hydrothermal approach. MQDs have good dispersity and high stability in aqueous suspension and exhibit a significantly larger direct bandgap (3.96 eV) compared to monolayer MoS2 nanosheets (1.89 eV). Pronounced blue‐shifts in the wavelengths of both the excitonic absorption and intrinsic state emission with activated strong luminescence at room temperature beyond monolayer MoS2 nanosheets is demonstrated. Unusual upconversion photoluminescence is also observed and is caused by two successive transfers of energy from the near‐infrared (NIR) absorption generated by the NAC capping reagent to the hexagonal structure of MQDs. Additional optical properties of MQDs may provide numerous exciting technological applications. Here, MQDs are demonstrated as a highly selective fluorescent reagent for detecting tetracycline hydrochloride under UV and NIR irradiation.
Metabolism of agrochemicals and related environmental chemicals based on cytochrome P450s in mammals and plants
Authors: Ohkawa Hideo , Inui Hideyuki
Published: July 2014

A yeast gene expression system originally established for mammalian cytochrome P450 monooxygenase cDNAs was applied to functional analysis of a number of mammalian and plant P450 species, including 11 human P450 species (CYP1A1, CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C18, CYP2C19, CYP2D6, CYP2E1 and CYP3A4). The human P450 species CYP1A1, CYP1A2, CYP2B6, CYP2C18 and CYP2C19 were identified as P450 species metabolising various agrochemicals and environmental chemicals. CYP2C9 and CYP2E1 specifically metabolised sulfonylurea herbicides and halogenated hydrocarbons respectively. Plant P450 species metabolising phenylurea and sulfonylurea herbicides were also identified mainly as the CYP71 family, although CYP76B1, CYP81B1 and CYP81B2 metabolised phenylurea herbicides. The transgenic plants expressing these mammalian and plant P450 species were applied to herbicide tolerance as well as phytoremediation of agrochemical and environmental chemical residues. The combined use of CYP1A1, CYP2B6 and CYP2C19 belonging to two families and three subfamilies covered a wide variety of herbicide tolerance and phytoremediation of these residues. The use of 2,4‐D‐and bromoxynil‐induced CYP71AH11 in tobacco seemed to enhance herbicide tolerance and selectivity. © 2014 Society of Chemical Industry
Mating competitiveness and life‐table comparisons between transgenic and Indian wild‐type Aedes aegypti L.
Authors: Patil Prabhakargouda B , Niranjan Reddy BP , Gorman Kevin , Seshu Reddy KV , Barwale Shirish R , Zehr Usha B , Nimmo Derric , Naish Neil , Alphey Luke
Published: July 2014

BACKGROUND

OX513A is a genetically engineered strain of Aedes aegypti carrying a repressible, dominantly inherited transgene that confers lethality in immature heterozygous progeny. Released male OX513A adults have proven to be effective for the localised suppression of wild Ae. aegypti, highlighting its potential in vector control. Mating and life‐table assessments were used to compare OX513A with reared Ae. aegypti strains collected from New Delhi and Aurangabad regions in India.

RESULTS

Mating proportions of New Delhi females versus males of OX513A or New Delhi strains were 0.52 and 0.48 respectively, indicating no discrimination by females against either strain, and males of both strains were equally competitive. Developmental time from first instar to adult emergence was significantly longer for OX513A (10.7 ± 0.04 days) than for New Delhi (9.4 ± 0.04 days) and Aurangabad strains (9.1 ± 0.04 days). Differences in mean longevities, female reproductive parameters and population growth parameters between the strains were non‐significant.

CONCLUSIONS

The laboratory study demonstrates that only minor life‐table variations of limited biological relevance exist between OX513A and Indian Ae. aegypti populations, and males had equal potential for mating competitiveness. Thus, results support the OX513A strain as a suitable candidate for continued evaluation towards sustainable management of Ae. aegypti populations in India. © 2014 Gangabishan Bhikulal Investment and Trading Limited. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.