bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanical behavior at nanoscale of chitosan‐coated PE surface
Authors: Stoleru (Paslaru) Elena , Tsekov Yuliy , Kotsilkova Rumiana , Ivanov Evgeni , Vasile Cornelia 
Published: May 2015

ABSTRACTChitosan coating of polyethylene (PE) was proposed as a new procedure to improve its biocompatibility and surface properties. The functionalization of the PE film surface by covalent bonding of chitosan coating and its effect on the surface mechanical properties, as surface elasticity, stiffness, and adhesion (that are important in different biological processes) were investigated by nano‐indentation, scratch, and atomic force microscopy. It has been established that chitosan grafting onto corona functionalized PE surface using various coupling agents significantly improves the surface hardness and elastic modulus although they decrease in depth of the layer. Compared to the neat PE substrate, the chitosan coated samples show significant improved friction properties and tear resistance. The surface roughness features correlate with the micro‐mechanical parameters. Therefore, the covalent immobilization of the chitosan onto PE leads to a stable coating with better mechanical performance being recommended as a promising material for medical applications and food packaging. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42344.
Synchronization of Instantaneous Coupled Harmonic Oscillators With Communication and Input Delays
Authors: Zhao Liyun , Wu Quanjun , Zhang Hua , Zhou Jin 
Published: May 2015

AbstractThis paper investigates the synchronization issue of instantaneous coupled harmonic oscillators with communication and input delays. A distributed synchronization algorithm is proposed for such oscillator systems, and some general algebraic criteria on exponential convergence are established for the algorithm. The main contributions of the present investigations include: (i) the directed network topology is first considered in the case of instantaneous interaction; (ii) both the time‐varying communication and input delays are simultaneously addressed; (iii) the effects of communication and input delays on synchronization performance of coupled harmonic oscillators are discussed. It is shown the communication delays have a more important impact than the input delays on determining synchronization dynamics of coupled harmonic oscillators. Explicitly, in absence of communication delays, coupled harmonic oscillators can achieve synchronization oscillatory motion, whereas, so long as communication delays are nonzero at infinite multiple impulsive times, its synchronization (or consensus) state is zero. Finally, numerical examples demonstrate the obtained theoretical results.
Engineered catalytic biofilms: Site‐specific enzyme immobilization onto E. coli curli nanofibers
Authors: Botyanszki Zsofia , Tay Pei Kun R. , Nguyen Peter Q. , Nussbaumer Martin G. , Joshi Neel S. 
Published: May 2015

ABSTRACTBiocatalytic transformations generally rely on purified enzymes or whole cells to perform complex transformations that are used on industrial scale for chemical, drug, and biofuel synthesis, pesticide decontamination, and water purification. However, both of these systems have inherent disadvantages related to the costs associated with enzyme purification, the long‐term stability of immobilized enzymes, catalyst recovery, and compatibility with harsh reaction conditions. We developed a novel strategy for producing rationally designed biocatalytic surfaces based on Biofilm Integrated Nanofiber Display (BIND), which exploits the curli system of E. coli to create a functional nanofiber network capable of covalent immobilization of enzymes. This approach is attractive because it is scalable, represents a modular strategy for site‐specific enzyme immobilization, and has the potential to stabilize enzymes under denaturing environmental conditions. We site‐specifically immobilized a recombinant α‐amylase, fused to the SpyCatcher attachment domain, onto E. coli curli fibers displaying complementary SpyTag capture domains. We characterized the effectiveness of this immobilization technique on the biofilms and tested the stability of immobilized α‐amylase in unfavorable conditions. This enzyme‐modified biofilm maintained its activity when exposed to a wide range of pH and organic solvent conditions. In contrast to other biofilm‐based catalysts, which rely on high cellular metabolism, the modified curli‐based biofilm remained active even after cell death due to organic solvent exposure. This work lays the foundation for a new and versatile method of using the extracellular polymeric matrix of E. coli for creating novel biocatalytic surfaces. Biotechnol. Bioeng. 2015;112: 2016–2024. © 2015 Wiley Periodicals, Inc.
‘Something That Unites Us All’: Understandings of St. Patrick's Day Parades as Representing the Irish National Group
Authors: O'Donnell Aisling T. , Muldoon Orla T. , Blaylock Danielle L. , Stevenson Clifford , Bryan Dominic , Reicher Stephen D. , Pehrson Samuel 
Published: May 2015

AbstractThe present study investigates how attendees at national celebratory crowd events—specifically St. Patrick's Day parades—understand the role of such events in representing and uniting the national community. We conducted semi‐structured interviews with people who attended St. Patrick's Day parades in either Dublin or Belfast. In year 1, full‐length interviews were conducted before and after the events (N = 17), and in years 1 and 2, shorter interviews were conducted during the events (year 1 N = 170; year 2 N = 142). Interview data were analysed using thematic analysis, allowing the identification of three broad themes. Participants reported that (i) the events extend the boundary of the national group, using participation to define who counts as Irish; (ii) the events strategically represent the nature of the national group, maximising positive images and managing stereotypical representations; and (iii) symbolism serves to unify the group but can also disrupt already fragile unity and so must be managed. Overall, this points to a strategic identity dimension to these crowd events. We discuss the implications of these findings for future research in terms of the role of large‐scale celebratory events in the strategic representation of everyday social identities. © 2015 The Authors. Journal of Community & Applied Social Psychology published by John Wiley & Sons Ltd.
Enzymatic Evidence for a Revised Congocidine Biosynthetic Pathway
Authors: Al‐Mestarihi Ahmad H. , Garzan Atefeh , Kim Josephine M. , Garneau‐Tsodikova Sylvie 
Published: May 2015

AbstractNaturally produced pyrrolamides, such as congocidine, are nonribosomal peptides that bind to the minor groove of DNA. Efforts to delineate the biosynthetic machinery responsible for their assembly have mainly employed genetic methods, and the enzymes responsible for their biosynthesis remain largely uncharacterized. We report the biochemical characterization of four proteins involved in congocidine formation: the adenylation‐thiolation (A–T) di‐domain Cgc18(1–610), its MbtH‐like partner SAMR0548, the AMP‐binding enzyme Cgc3*, and the T domain Cgc19. We assayed the ATP‐dependent activation of various commercially available and chemically synthesized compounds with Cgc18(1–610) and Cgc3*. We report the revised substrate specificities of Cgc18(1–610) and Cgc3*, and loading of 4‐acetamidopyrrole‐2‐carboxylic acid onto Cgc19. Based on these biochemical studies, we suggest a revised congocidine biosynthetic pathway.
Use of intracardiac echocardiography to guide percutaneous transluminal mitral commissurotomy
Authors: Saji Mike , Ragosta Michael , Dent John , Lim D. Scott 
Published: May 2015

ObjectivesTo report the efficacy and safety of the use adjunctive intracardiac echocardiography (ICE) during percutaneous transluminal mitral commissurotomy (PTMC) in patients without transesophageal echocardiography (TEE).BackgroundPatients with mitral stenosis are at a high risk of developing a left atrial (LA) thrombus. Traditionally, TEE has been used prior to PTMC to identify the presence of LA thrombi. There have been no reports of the use of ICE to assess the LA for thrombi prior to PTMC.MethodsWe retrospectively reviewed 20 patients who underwent ICE prior to PTMC. All PTMC procedures were performed via the antegrade transvenous approach using an Inoue balloon. Initially, ICE was used from the right atrium to confirm the absence of a thrombus on the left side of the septum and was subsequently used to guide the transseptal puncture. Following these procedures, the ICE was advanced into the LA through a transseptal sheath to visualize the LAA.ResultsVisualization of the thrombus/spontaneous echo contrast was considered to be diagnostic in all cases. Seventy percent of the patients were discharged on day after the procedure. No patients required intubation during the procedure, and there were no complications that could be attributed to the use of ICE. At six months after the PTMC, the incidence of stroke was zero.ConclusionsICE‐guided PTMC offers excellent visualization of the LA and the LAA with satisfactory clinical outcomes and low risk. As a part of the PTMC procedure, ICE safely provides a valid alternative to a separate TEE procedure. © 2015 Wiley Periodicals, Inc.
Nanocrystalline Titanosilicate–Acetylcholinesterase Electrochemical Biosensor for the Ultra‐Trace Detection of Toxic Organophosphate Pesticides
Authors: Kaur Balwinder , Srivastava Rajendra , Satpati Biswarup 
Published: May 2015

AbstractIn this work, nanocrystalline titanosilicate and ZSM‐5 were synthesized in the presence of propyltriethoxy silane as an additive. Electrochemical biosensors based on nanocrystalline zeolites were fabricated through the covalent immobilization of the enzyme acetylcholinesterase for the ultra‐trace detection of toxic organophosphate pesticides such as malathion, parathion methyl, monocrotopos, and dichlorvos. The results show that, among the zeolite‐based biosensors investigated in this study, the nanocrystalline titanosilicate‐based acetylcholinesterase biosensor exhibited the highest electrocatalytic activity. The nanocrystalline titanosilicate‐based acetylcholinesterase biosensor exhibited excellent sensitivity, selectivity, stability, linear range, and limit of detection. The analytical performance of the developed sensor was demonstrated in the determination of these pesticides in a range of real samples (apples, cabbages, tap water, and river water) with satisfactory recovery.
Silver Quantum Cluster (Ag9)‐Grafted Graphitic Carbon Nitride Nanosheets for Photocatalytic Hydrogen Generation and Dye Degradation
Authors: Sridharan Kishore , Jang Eunyong , Park Jung Hyun , Kim Jong‐Ho , Lee Jung‐Ho , Park Tae Joo 
Published: May 2015

AbstractWe report the visible‐light photocatalytic properties of a composite system consisting of silver quantum clusters [Ag9(H2MSA)7] (H2MSA=mercaptosuccinic acid) embedded on graphitic carbon nitride nanosheets (AgQCs‐GCN). The composites were prepared through a simple chemical route; their structural, chemical, morphological, and optical properties were characterized by using X‐ray diffraction (XRD), energy dispersive X‐ray spectroscopy, transmission electron microscopy, UV/Vis diffuse reflectance spectroscopy, and photoluminescence spectroscopy. Embedment of [Ag9(H2MSA)7] on graphitic carbon nitride nanosheets (GCN) resulted in extended visible‐light absorption through multiple single‐electron transitions in Ag quantum clusters and an effective electronic structure for hydroxyl radical generation, which enabled increased activity in the photocatalytic degradation of methylene blue and methyl orange dye molecules compared with pristine GCN and silver nanoparticle‐grafted GCN (AgNPs‐GCN). Similarly, the amount of hydrogen generated by using AgQCs‐GCN was 1.7 times higher than pristine GCN. However, the rate of hydrogen generated using AgQCs‐GCN was slightly less than that of AgNPs‐GCN because of surface hydroxyl radical formation. The plausible photocatalytic processes are discussed in detail.
Probing Reversible Chemistry in Coenzyme B12‐Dependent Ethanolamine Ammonia Lyase with Kinetic Isotope Effects
Authors: Jones Alex R. , Rentergent Julius , Scrutton Nigel S. , Hay Sam 
Published: May 2015

AbstractCoenzyme B12‐dependent enzymes such as ethanolamine ammonia lyase have remarkable catalytic power and some unique properties that enable detailed analysis of the reaction chemistry and associated dynamics. By selectively deuterating the substrate (ethanolamine) and/or the β‐carbon of the 5′‐deoxyadenosyl moiety of the intrinsic coenzyme B12, it was possible to experimentally probe both the forward and reverse hydrogen atom transfers between the 5′‐deoxyadenosyl radical and substrate during single‐turnover stopped‐flow measurements. These data are interpreted within the context of a kinetic model where the 5′‐deoxyadenosyl radical intermediate may be quasi‐stable and rearrangement of the substrate radical is essentially irreversible. Global fitting of these data allows estimation of the intrinsic rate constants associated with CoC homolysis and initial H‐abstraction steps. In contrast to previous stopped‐flow studies, the apparent kinetic isotope effects are found to be relatively small.
Der Nebelkammer‐Reaktor – Neuartiges Reaktorkonzept für anspruchsvolle Kultivierungen
Authors: Dreimann Janis , Schmidt Timo , Tscheschke Bernd , v.d. Ruhr Jürgen W. , Just Lothar , Stahl Frank , Scheper Thomas 
Published: May 2015

AbstractEin neuer Bioreaktortyp, der Nebelkammer‐Reaktor, wird vorgestellt. Im Unterschied zu den bisherig verwendeten submersen Kultur‐ bzw. Bioreaktorverfahren werden im Nebelkammer‐Reaktor Zellverbände mittels eines Aerosols aus ultraschallzerstäubtem Nährmedium umhüllt. Die kontinuierlich erzeugten Aerosoltröpfchen setzen sich auf den Zellen ab und ermöglichen so eine besonders effektive und scherstressarme Versorgung der Zellen mit Gasen und Nährstoffen sowie eine größere Unabhängigkeit von Form und Größe der eingesetzten Konstrukte.
Glycerin‐Oxidation mit magnetisch abtrennbaren Nanokatalysatoren
Authors: Behr Arno , Irawadi Ken Aulia 
Published: May 2015

AbstractNanopartikuläre Gold‐ und Gold‐Platin‐Katalysatoren aufgetragen auf Magnetit als Trägermaterial wurden zur aeroben Glycerin‐Oxidation eingesetzt. Mittels Transmissionselektronenmikroskopie konnte für den Gold‐Katalysator eine ikosaedrische Morphologie und für den Gold‐Platin‐Katalysator eine blütenähnliche Struktur nachgewiesen werden. Analysen mit dynamischer Lichtstreuung bestätigten für beide Katalysatortypen eine mittlere Partikelgröße von 30 nm und eine gute Stabilität über einen Zeitraum von mindestens vier Wochen. Durch eine magnetische Abtrennung konnten beide Katalysatoren erfolgreich aus dem Reaktionsmedium zurückgewonnen werden. Ein Katalysatoraustrag wurde dabei nicht beobachtet und die erfolgreich wiederverwendeten Katalysatoren wiesen nur geringe Veränderungen auf.
Untersuchung des Druckverhaltens tetraederförmiger Agglomerate
Authors: Müller Peter , Tomas Jürgen 
Published: May 2015

AbstractUnter Verwendung eines Pelletiertellers wurden mittels Aufbauagglomeration tetraederförmige Agglomerate aus makroskopischen kugelförmigen Primärpartikeln und Bindemittel hergestellt. Tetraederförmige Agglomerate bestehen aus vier kugelförmigen Primärpartikeln, wobei drei Partikel eine Grundfläche bilden, auf die das vierte Partikel zentrisch angeordnet ist. Das Druck‐ und Bruchverhalten der Agglomerate wurde mittels Diametraldruckversuchen analysiert. Der Einfluss der Primärpartikelgröße und der Bindemittelkonzentration wurden ebenfalls bestimmt. Zusätzlich wurde ein Ansatz für die theoretische Beschreibung der Kontaktdeformation entwickelt.
History of high‐risk HPV and Pap test results in a large cohort of patients with invasive cervical carcinoma: Experience from the largest women's hospital in China
Authors: Tao Xiang , Griffith Christopher C. , Zhou Xiangrong , Wang Zhiheng , Yan Yabin , Li Zaibo , Zhao Chengquan 
Published: May 2015

BACKGROUNDCurrent cervical cancer screening guidelines recommend screening with a Papanicolaou (Pap) test or by cotesting (Pap and human papillomavirus [HPV]). Given the importance of high‐risk HPV (hrHPV) infection in the development of cervical cancer, some studies are now suggesting the use of primary hrHPV testing as a possible screening modality. To gain further insight into the role of both Pap testing and hrHPV testing, the authors examined prior screening results in a population of Chinese patients with invasive cervical carcinoma.METHODSCases with a histologic diagnosis of invasive cervical carcinoma were retrieved from the Obstetrics and Gynecology Hospital of Fudan University from January 2011 to October 2014. Prior hrHPV testing and Pap test results within 3 years before the cancer diagnosis were recorded.RESULTSOf 3714 patients with invasive cervical carcinoma, over a 46‐month period, 525 had prior hrHPV testing using Hybrid Capture 2 within 3 years and 238 patients had Pap cytology testing within 1 year before the histological diagnosis. Within the 1‐year period before diagnosis, the overall hrHPV‐negative rate was 15.5% (74 of 477 patients) and the Pap‐negative rate was also 15.5% (37 of 238 patients). Only 9 of 231 patients with both hrHPV testing and Pap testing (3.9%) had a double‐negative result. Compared with squamous cell carcinoma, adenocarcinoma has significantly higher rates of prior negative results with both hrHPV and Pap cytology.CONCLUSIONSThe results of the current study demonstrated prior results of hrHPV testing and Pap cytology in a population of women in China who had not undergone intensive prior screening. Both hrHPV testing and Pap cytology were found to have similar negative rates in this population and, not surprisingly, there were fewer women who had negative testing results using both testing modalities. Cancer (Cancer Cytopathol) 2015;123:421‐7. © 2015 American Cancer Society.
Pregnancy distress gets under fetal skin: Maternal ambulatory assessment & sex differences in prenatal development
Authors: Doyle Colleen , Werner Elizabeth , Feng Tianshu , Lee Seonjoo , Altemus Margaret , Isler Joseph R. , Monk Catherine 
Published: May 2015

ABSTRACTPrenatal maternal distress is associated with an at‐risk developmental profile, yet there is little fetal evidence of this putative in utero process. Moreover, the biological transmission for these maternal effects remains uncertain. In a study of n = 125 pregnant adolescents (ages 14–19), ambulatory assessments of daily negative mood (anger, frustration, irritation, stress), physical activity, blood pressure, heart rate (every 30 min over 24 hr), and salivary cortisol (six samples) were collected at 13–16, 24–27, 34–37 gestational weeks. Corticotropin‐releasing hormone, C‐reactive protein, and interleukin 6 from blood draws and 20 min assessments of fetal heart rate (FHR) and movement were acquired at the latter two sessions. On average, fetuses showed development in the expected direction (decrease in FHR, increase in SD of FHR and in the correlation of movement and FHR (“coupling”)). Maternal distress characteristics were associated with variations in the level and trajectory of fetal measures, and results often differed by sex. For males, greater maternal 1st and 2nd session negative mood and 2nd session physical activity were associated with lower overall FHR (p < .01), while 1st session cortisol was associated with a smaller increase in coupling (p < .01), and overall higher levels (p = .05)—findings suggesting accelerated development. For females, negative mood, cortisol, and diastolic blood pressure were associated with indications of relatively less advanced and accelerated outcomes. There were no associations between negative mood and biological variables. These data indicate that maternal psychobiological status influences fetal development, with females possibly more variously responsive to different exposures. © 2015 Wiley Periodicals, Inc. Dev Psychobiol 57: 607–625, 2015.
Does sex‐biased dispersal account for the lack of geographic and host‐associated differentiation in introduced populations of an aphid parasitoid?
Authors: Zepeda‐Paulo Francisca , Lavandero Blas , Mahéo Frédérique , Dion Emilie , Outreman Yannick , Simon Jean‐Christophe , Figueroa Christian C. 
Published: May 2015

AbstractHost recognition and use in female parasitoids strongly relies on host fidelity, a plastic behavior which can significantly restrict the host preferences of parasitoids, thus reducing the gene flow between parasitoid populations attacking different insect hosts. However, the effect of migrant males on the genetic differentiation of populations has been frequently ignored in parasitoids, despite its known impact on gene flow between populations. Hence, we studied the extent of gene flow mediated by female and male parasitoids by assessing sibship relationships among parasitoids within and between populations, and its impact on geographic and host‐associated differentiation in the aphid parasitoid Aphidius ervi. We report evidences of a high gene flow among parasitoid populations on different aphid hosts and geographic locations. The high gene flow among parasitoid populations was found to be largely male mediated, suggested by significant differences in the distribution of full‐sib and paternal half‐sib dyads of parasitoid populations.
Basic Properties of Two‐Dimensional Composite Dynamical System with Spike Noise
Authors: TANAKA DAIKI , ASAHARA HIROYUKI , AIHARA KAZUYUKI , KOUSAKA TAKUJI 
Published: May 2015

SUMMARYBifurcation phenomena in a composite dynamic system are studied in order to understand the basic properties of systems. Recently, it has been reported that unavoidable non‐ideal switching, e.g., spike noise or a time delay, occurs due to switching and seriously affects the behavior of the trajectory in a composite dynamical system operating in high‐frequency switching ranges. We have analyzed the basic properties of a simple one‐dimensional composite dynamical system with nonideal switching in order to understand the essence of the dynamical effects of nonideal switching. In the engineering field, there are many two‐ or more dimensional systems. Naturally, nonideal switching can occur in two‐ or more dimensional systems. However, no paper analyzes the effect of nonideal switching in such systems. In this paper, we study the basic properties of a two‐dimensional composite dynamical system with spike noise. First, we describe a model of a two‐dimensional composite dynamical system. Next, the behavior of the waveforms in a system with ideal switching and a system with spike noise is shown. Then, we sample the data of the waveforms in every period for the external force and define a Poincaré map. Finally, using the Poincaré map, we derive two‐parameter bifurcation diagrams and discuss the basic properties of a system with spike noise.