bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of Triplet States of Two Different Ligands in the Sensitized Emission of LnIII (EuIII, TbIII) in d–f Hybrid Tetranuclear Heterometal (ZnII2LnIII2, CdII2LnIII2) Complexes
Authors: Samanta Swarna Kamal , Abtab Sk Md Towsif , Sardar Pinki Saha , Sanyal Sagarika , Chaudhury Muktimoy , Ghosh Sanjib
Published: June 2014

The crystal structures of synthesized d–f hybrid tetranuclear heterometal ZnII2EuIII2 and CdII2EuIII2 complexes, involving a pair of carboxylate ligands in a rare μ4‐η2:η2 bridging mode, reveal that the metal centers are arranged alternately in a rhombic plane within 4 Å from each other. The ZnII2EuIII2 and ZnII2TbIII2 complexes exhibit efficient sensitization compared with the CdII‐analogues. Under proper excitation, the lowest ππ* triplet states of both ligands N,N′‐dimethyl‐N,N′‐bis(2‐hydroxy‐3,5‐dimethylbenzyl)ethylenediamine (H2L) and hexafluoroacetylacetone (Hhfac) act as donors, implying synergistic energy transfer (ET). The ratio of the sensitized efficiency for the heterocomplexes in different media at 298 K and 77 K, based on the observed transients, reveal the role of ZnII and CdII in the ET process. The ratio of the ET rate constants obtained from the time‐resolved phosphorescence of the complexes at 77 K and time‐dependent DFT calculations on homocomplexes support this contention.
A Neutral 1D Coordination Polymer Constructed from the NiII Complex of the N‐Phosphorylated Thiourea PhNHC(S)NHP(O)(OPh)2 and Pyrazine: A Single‐Source Precursor for Nickel Nanoparticles
Authors: Babashkina Maria G. , Safin Damir A. , Robeyns Koen , Garcia Yann
Published: June 2014

The N‐phosphorylated thiourea PhNHC(S)NHP(O)(OPh)2 (HL) was synthesized by the reaction of PhNH2 and (PhO)2P(O)NCS. Reaction of the KL salt, generated in situ, with NiCl2 leads to pale violet [NiL2] with a 1,3‐N,S‐ coordination mode of the ligands. Interaction of [NiL2] with pyrazine (pz) yields the 1:1 coordination polymer [NiL2pz]n. An unexpected change in the coordination mode of the phosphorus‐containing ligands L from 1,3‐N,S‐ to 1,5‐O,S‐ was found in [NiL2pz]n upon coordination of additional donor ligands. [NiL2pz]n dissolved in tri‐n‐octylphosphine (TOP) was decomposed in hot hexadecylamine to give capped face‐centered cubic Ni nanoparticles with an average particle size of 17(2) nm.
Twin Polymerization: A Unique and Efficient Tool for Supporting Silver Nanoparticles on Highly Porous Carbon and Silica
Authors: Schliebe Christian , Gemming Thomas , Mertens Lutz , Mehring Michael , Lang Heinrich
Published: June 2014

A convenient approach for the straightforward synthesis of highly dispersed silver nanoparticles (below 5 nm) in a carbon or silicon dioxide matrix through twin polymerization is reported. The obtained mainly microporous carbon (type I isotherm) and mesoporous silica materials (type IV isotherm) exhibit a rather high surface area (carbon = 1034 m2 g–1, SiO2 = 666 m2 g–1).
Design and Study of Peptides Containing 1:1 Left‐ and Right‐Handed Helical Patterns from Aminopyrancarboxylic Acids
Authors: Sharma Gangavaram V. M. , Ravindranath Hajari , Bhaskar Akkala , Jeelani Basha Shaik , Gurava Reddy Potti Reddy Gari , Sirisha Katukuri , Sarma Akella V. S. , Hofmann Hans‐Jörg
Published: June 2014

(R,R)‐ and (S,S)‐aminopyrancarboxylic acids (APyCs) were used in the design of mixed β‐ and α/β‐peptides in alternation with β‐hGly and L‐Ala/D‐Ala, respectively. The enantiomeric β‐ and α/β‐tetrapeptides were then coupled in a 1:1 fashion to give octapeptides with 12/10‐ and 9/11‐mixed helices, respectively. The structure of the helices, with their characteristic hydrogen‐bonding patterns and an additional stabilizing interaction between peptide‐bond NH groups and pyran‐ring oxygen atoms, was investigated by NMR spectroscopy, molecular dynamics, and quantum chemical studies. The presence of equal parts of left‐ and right‐handed helices was confirmed by the cancellation of their respective CD patterns. Despite the disruption of the hydrogen bonding in the transition region, the helical conformation was maintained in the octamers. This study demonstrates the possibility of accommodating helices of opposite handedness within the same peptide.
Elucidation of the Reaction Mechanism of ortho→α Transmetalation Reactions of Alkyl Aryl Sulfone Carbanions
Authors: Řehová Lucie , Jahn Ullrich
Published: June 2014

The sulfonyl group, as an electron‐accepting function, displays a strong acidifying effect on neighboring α‐hydrogen atoms, leading to their deprotonation by bases. Recently, reversal of the metalation selectivity of α,γ‐branched alkyl aryl sulfones was described, which instead undergo directed ortho‐metalation with good regioselectivity, despite having a more acidic α‐proton. Upon warming, a transmetalation to the α‐carbanion proceeds; however, nothing is known about the course of this transmetalation. Here, a mechanistic study is presented that sheds light on the facility of the initial metalation and the subsequent transmetalation. Large kinetic isotope effects were observed for both the initial deprotonation and the ortho→α transmetalation, which strongly influence the initial metalation selectivity. The results of a kinetic investigation of the transmetalation and a crossover study indicate that a concerted intermolecular pathway, either from an aggregate or from a monomeric aryllithium, prevails. The potential involvement of a stepwise process via ortho,α‐dilithium intermediates was investigated, but no hint of their involvement was found.
Asymmetric Synthesis of 2‐Heteroaryl Cyclic Amines: Total Synthesis of (–)‐Anabasine
Authors: Sallio Romain , Lebrun Stéphane , Gigant Nicolas , Gillaizeau Isabelle , Deniau Eric
Published: June 2014

A new and concise method for the synthesis of enantioenriched 2‐heteroaryl cyclic amines was developed through an intramolecular chirality transfer. The influence of the nature of both ring size and heteroaryl moiety was investigated. The versatility of this reaction was demonstrated by the enantioselective synthesis of (–)‐anabasine.
A Formal Synthesis of Herboxidiene/GEX1A
Authors: Yadav Jhillu S. , Reddy G. Madhusudhan , Anjum S. Rehana , Reddy B. V. Subba
Published: June 2014

A formal synthesis of herboxidiene/GEX 1A is described. This approach demonstrates successful application of the Prins cyclization for the construction of the tetrahydropyran core of the target molecule. The chirality of the side chain has been established through the Sharpless asymmetric dihydroxylation and Evan's alkylation. The olefin cross‐metathesis was applied to couple both key fragments.
Synthesis of Substituted Imidazolidines: Base‐Stable Precursors of 4,5‐Dihydro‐1H‐imidazol‐3‐ium Salts and N‐Heterocyclic Carbenes
Authors: Egert Meike , Walther Sebastian , Plenio Herbert
Published: June 2014

The present work establishes a new synthetic route that leads to substituted azolium salts. The base stable 1‐(4‐bromo‐2,6‐diisopropylphenyl)‐3‐(2,6‐diisopropylphenyl)imidazolidine and 1,3‐bis(4‐bromo‐2,6‐diisopropylphenyl)imidazolidine were synthesized and the 4‐Br substituents converted into various functional groups through Br/Li exchange or Pd‐catalyzed cross‐coupling reactions (Suzuki, Sonogashira, and vinylation). The substituted imidazolidines were oxidized, by using chloranil or N‐bromosuccinimide, to provide the respective azolium salts, which are convenient precursors to N‐heterocyclic carbenes.
Pyridyl‐Decorated Self‐Folding Heptaamide Cavitands as Ligands in the Rhodium‐Catalyzed Hydrogenation of Norbornadiene
Authors: Korom Saša , Ballester Pablo
Published: June 2014

The different binding geometries exhibited in solution by the RhI cationic complexes of three regioisomeric self‐folding heptaamide cavitands, each decorated with one pyridyl group at the upper rim, are taken into account to explain the diverse distributions of products obtained when these complexes are employed as catalysts for the hydrogenation of norbornadiene.
Exposure to Perfluoroalkyl Substances and Sperm DNA Global Methylation in Arctic and European Populations
Authors: Leter Giorgio , Consales Claudia , Eleuteri Patrizia , Uccelli Raffaella , Specht Ina O. , Toft Gunnar , Moccia Tania , Budillon Alfredo , Jönsson Bo A.G. , Lindh Christian H. , Giwercman Aleksander , Pedersen Henning S. , Ludwicki Jan K. , Zviezdai Valentyna , Heederik Dick , Bonde Jens Peter E. , Spanò Marcello
Published: June 2014

Perfluoroalkyl substances (PFASs) are widely used in a variety of industrial processes and products, and have been detected globally in humans and wildlife. PFASs are suspected to interfere with endocrine signaling and to adversely affect human reproductive health. The aim of the present study was to investigate the associations between exposure to PFASs and sperm global methylation levels in a population of non‐occupationally exposed fertile men. Measurements of PFASs in serum from 262 partners of pregnant women from Greenland, Poland and Ukraine, were also carried out by liquid chromatography tandem mass spectrometry. Perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA) were detected in 97% of the blood samples. Two surrogate markers were used to assess DNA global methylation levels in semen samples from the same men: (a) average DNA methylation level in repetitive DNA sequences (Alu, LINE‐1, Satα) quantified by PCR‐pyrosequencing after bisulfite conversion; (b) flow cytometric immunodetection of 5‐methyl‐cytosines. After multivariate linear regression analysis, no major consistent associations between PFASs exposure and sperm DNA global methylation endpoints could be detected. However, since weak but statistically significant associations of different PFASs with DNA hypo‐ and hyper‐methylation were found in some of the studied populations, effects of PFASs on sperm epigenetic processes cannot be completely excluded, and this issue warrants further investigation. Environ. Mol. Mutagen. 55:591–600, 2014. © 2014 Wiley Periodicals, Inc.
Signal Processing and Stochastic Filtering for EIS Based PHM of Fuel Cell Systems
Authors: Gašperin M. , Boškoski P. , Debenjak A. , Petrovčič J.
Published: June 2014

This paper presents an alternative computational method for on‐line estimation and tracking of the impedance of PEM fuel cell systems. The method is developed in order to provide the information to diagnostics and health management system. Proper water management remains the main issue influencing the reliability and durability of PEM fuel cell technology. While literature reviews reveal the thorough understanding of the underlying processes and extensive experimental work, the existing implementations rely on expensive hardware or time consuming computational methods. In this scope, we will show how the characteristic values of the fuel cell impedance, required by the diagnostic system, can be computed by robust and computationally efficient algorithms, which are suitable for implementation in embedded systems. The methods under consideration include continuous‐time wavelet transform (CWT) and extended Kalman filter (EKF). The CWT is a time‐frequency technique, which is suitable for tracking transient signal components. The EKF is a stochastic signal processing method, which provides confidence measures for the estimates. The paper shows, that both methods provide accurate estimates for diagnostics of FCS and can perform on‐line tracking of these features. The performance of the algorithms is validated on experimental data from a commercial fuel cell stack.
Direct Hybridization Fuel Cell – Ultracapacitors
Authors: Morin B. , Van Laethem D. , Turpin C. , Rallières O. , Astier S. , Jaafar A. , Verdu O. , Plantevin M. , Chaudron V.
Published: June 2014

It is now well recognized that highly dynamic power demands accelerate the ageing of a fuel cell. A solution is to hybridize it with an electrochemical storage device (ultracapacitors, Li‐ion battery...). Whatever the technique implemented to manage energy, the hybridization principle forces the storage device to take in charge the rapid power changes to protect the fuel cell. Several electrical architectures are possible to interconnect the fuel cell and the storage device: indirect hybridization via power converters, or direct hybridization without power converters. The work here focuses on direct hybridization between a fuel cell and ultracapacitors.

Classically, this kind of connection concerns the hybridization of a fuel cell stack with an ultracapacitors' pack. The authors here investigate another rather original option by implementing this hybridization at the scale of each cell of a fuel cell stack. In this approach, each elementary ultracapacitor can be connected either to one cell or to two cells.

Before applying the concept to a real fuel cell stack (the final objective), the authors studied the concepts with single cells. This paper is going to present the intensive experimental works achieved to apprehend the principles. Static and dynamics properties of such hybridization are analyzed and modeled.
Glial cells suppress postencephalitic CD8+ T lymphocytes through PD‐L1
Authors: Schachtele Scott J. , Hu Shuxian , Sheng Wen S. , Mutnal Manohar B. , Lokensgard James R.
Published: June 2014

Engagement of the programmed death (PD)−1 receptor on activated cells by its ligand (PD‐L1) is a mechanism for suppression of activated T‐lymphocytes. Microglia, the resident inflammatory cells of the brain, are important for pathogen detection and initiation of innate immunity, however, a novel role for these cells as immune regulators has also emerged. PD‐L1 on microglia has been shown to negatively regulate T‐cell activation in models of multiple sclerosis and acute viral encephalitis. In this study, we investigated the role of glial cell PD‐L1 in controlling encephalitogenic CD8+ T‐lymphocytes, which infiltrate the brain to manage viral infection, but remain to produce chronic neuroinflammation. Using a model of chronic neuroinflammation following murine cytomegalovirus (MCMV)‐induced encephalitis, we found that CD8+ T‐cells persisting within the brain expressed PD‐1. Conversely, activated microglia expressed PD‐L1. In vitro, primary murine microglia, which express low basal levels of PD‐L1, upregulated the co‐inhibitory ligand on IFN‐γ‐treatment. Blockade of the PD‐1: PD‐L1 pathway in microglial: CD8+ T‐cell co‐cultures increased T‐cell IFN‐γ and interleukin (IL)−2 production. We observed a similar phenomenon following blockade of this co‐inhibitory pathway in astrocyte: CD8+ T‐cell co‐cultures. Using ex vivo cultures of brain leukocytes, including microglia and CD8+ T‐cells, obtained from mice with MCMV‐induced chronic neuroinflammation, we found that neutralization of either PD‐1 or PD‐L1 increased IFN‐γ production from virus‐specific CD8+ T‐cells stimulated with MCMV IE1168–176 peptide. These data demonstrate that microglia and astrocytes control antiviral T‐cell responses and suggest a therapeutic potential of PD1: PD‐L1 modulation to manage the deleterious consequences of uncontrolled neuroinflammation. GLIA 2014;62:1582–1594
Gender influence on schizophrenia‐relevant abnormalities in a cuprizone demyelination model
Authors: Valeiras Brenda , Rosato Siri María Victoria , Codagnone Martín , Reinés Analía , Pasquini Juana María
Published: June 2014

The aim of this study was to determine whether early demyelination can impact behavior in young adulthood. For this purpose, albino Wistar rats of either sex were exposed to cuprizone (CPZ) in two different intoxication protocols: one group was intoxicated before weaning (CPZ‐BW), from postnatal day 7 (P7) to P21, through maternal milk, whereas the other group was intoxicated after weaning (CPZ‐AW), from P21 to P35. After treatment, rats were returned to a normal diet until P90 when behavioral studies were performed. Both treatments produced marked demyelination in the corpus callosum and retraction of cortical myelin fibers. The subsequent normal diet allowed for effective remyelination at P90. Interestingly, CPZ‐AW correlated with significant behavioral and neurochemical changes in a gender‐dependent manner. CPZ‐AW treatment altered both the number of social activities and the latency to the first social interaction in males, while also highly compromising recognition‐related activities. In addition, only P90 males treated AW showed a hyperdopaminergic striatum, confirmed by an increase in tyrosine hydroxylase expression and in dopamine levels. Our results suggest that the timing of demyelination significantly influences the development of altered behavior, particularly in adult males. GLIA 2014;62:1629–1644
Behavioral skills training to improve installation and use of child passenger safety restraints
Authors: Himle Michael B. , Wright Kalon A.
Published: June 2014

The risk for serious injury and death to children during motor vehicle accidents can be greatly reduced through the correct use of child passenger safety restraints (CPSRs). Unfortunately, most CPSRs are installed or used incorrectly. This study examined the effectiveness of behavioral skills training (BST) to teach 10 participants to install rear‐facing CPSRs correctly using a multiple baseline design. Results show that installation errors were common for all participants during baseline. After BST, all 10 participants were able to install the rear‐facing CPSR without error. An extension probe to assess whether the skills taught during BST extended to forward‐facing installation showed that each participant made at least 1 critical error.
Effects of sodium acetate buffer on chitosan sponge properties andin vivodegradation in a rat intramuscular model
Authors: Parker Ashley Cox , Smith James Keaton , Reves Benjamin , Jennings Jessica Amber , Bumgardner Joel D. , Haggard Warren O.
Published: June 2014

Chitosan sponges were developed for adjunctive local antibiotic delivery to reduce bacteria in wounds. There is a need to increase sponge degradation for rapid clearance from the wound site during initial wound care. This work examined the effect of using 0.25Msodium acetate buffers, at pH 4.6 or 5.6, to fabricate sponges with an amorphous chitosan polymer structure. Sponges were evaluated for their crystallinity, thermal, spectroscopic, and morphological properties, in addition toin vitrodegradation, and cytocompatibility analysis using normal human dermal fibroblasts.In vivodegradation and biocompatibility were also examined after 4 and 10 days in rat intramuscular tissues. Both buffered chitosan sponge variations exhibited decreases in crystallinity and thermal decomposition temperatures, and increases in surface roughness, which resulted in over 40% increases in degradation over 10 daysin vitrocompared to the neutral sponges. There were no significant differences between sponges duringin vivodegradation over 10 days with respect to histomorphometric analysis of the recovered sponges. These results demonstrated that the acetate buffer did change characteristic chitosan sponge material properties, and increasing thein vivosponge degradation rate will require balancing material characteristics and processing. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 387–396, 2015.
Generalized Balanced Tournament Packings and Optimal Equitable Symbol Weight Codes for Power Line Communications
Authors: Chee Y. M. , Kiah H. M. , Ling A. C. H. , Wang C.
Published: June 2014

Generalized balanced tournament packings (GBTPs) extend the concept of generalized balanced tournament designs introduced by Lamken and Vanstone (1989). In this paper, we establish the connection between GBTPs and a class of codes called equitable symbol weight codes (ESWCs). The latter were recently demonstrated to optimize the performance against narrowband noise in a general coded modulation scheme for power line communications. By constructing classes of GBTPs, we establish infinite families of optimal ESWCs with code lengths greater than alphabet size and whose narrowband noise error‐correcting capability to code length ratios do not diminish to zero as the length grows.
Pigment identification of an illuminated mediaeval manuscriptDe Civitate Deiby means of a portable Raman equipment
Authors: Lauwers Debbie , Cattersel Vincent , Vandamme Ludo , Van Eester Annabel , De Langhe Kaat , Moens Luc , Vandenabeele Peter
Published: June 2014

Direct identification of pigments in mediaeval illuminated manuscripts was one of the first applications of Raman spectroscopy in art and archaeology. In previousin situanalysis of handwritings, the equipment was typically provided with a single excitation source. In this work, a portable Raman spectrometer (EZRAMAN‐I‐DUAL Raman system) is introduced to characterise the pigments used in an important illuminated mediaeval manuscript,De Civitate Dei(Library in Bruges, Ms.106). Characteristics important for thesein situmeasurements were discussed. We introduce a set‐up that allows stable positioning of the equipment and point out the advantage of the availability of two lasers, which are part of the instrument. Good performance of the introduced Raman spectrometer, to allow pigment identification in a short time, is proved. Finally, pigments such as lead white (2PbCO3 · Pb(OH)2), lead–tin yellow type I (Pb2SnO4), malachite (Cu2CO3(OH)2), mosaic gold (SnS2), vermillion (HgS), carbon black (C), red lead (Pb3O4) and azurite (Cu3(CO3)2(OH)2) could be identified. These pigments were often used in mediaeval artworks and contribute to the enrichment of information of the materials used by the illuminator. Copyright © 2014 John Wiley & Sons, Ltd.
Relative intensity correction of Raman optical activity spectra facilitates extending the spectral region
Authors: Profant Václav , Pazderková Markéta , Pazderka Tomáš , Maloň Petr , Baumruk Vladimír
Published: June 2014

Using home‐built Raman optical activity (ROA) spectrometer and a relative intensity correction for different instrument responses, we report ROA spectra beyond the traditionally utilized spectral region of 200–2500 cm−1. With three different interchangeable gratings covering partially overlapping spectral regions, we can study ROA in the whole region of fundamental molecular vibrations (150–4000 cm−1). Complete panoramic spectra are assembled from subparts collected with different gratings after a relative intensity correction based on the National Institute of Science and Technology standards known from the analogous application in Raman and fluorescence spectroscopy. Using this setup, we report the still little known ROA from C–H and C–D stretching region of the testing substances α‐pinene and a tricyclic spirodilactam. The intensity‐corrected experimental data were compared with calculated ROA and Raman spectra of these substances both with and without anharmonic corrections. A comparison revealed that above 1200 cm−1, the anharmonic correction provides a clear improvement of the agreement. While the calculation of Raman spectra achieves already good accuracy, the analogous ROA calculations still need further development. Copyright © 2014 John Wiley & Sons, Ltd.
Shoot‐through current reduction scheme for low power LTPS TFT programmable shift register
Authors: Song Eunji , Nam Hyoungsik
Published: June 2014

This paper proposes a programmable pulse width shift register where an output pulse width is adjusted only by changing a start pulse width without any additional signals and reconfiguration for the pre‐charging scheme of high resolution and high frame rate active‐matrix flat‐panel displays. In addition, the overall power consumption of a proposed circuitry is dramatically reduced by alleviating the shoot‐through current of an interval inverter, compared with the previous shift registers with the programmable or fixed output pulse width. The proposed shift register is verified by the simulation program with integrated circuit emphasis (SPICE) simulation at low temperature poly‐Si thin film transistor process for 50 stages. The proposed shift register lessens the power consumption by 34% and 54% for the output pulse widths of two and 10 line times, respectively, compared with those of the previous shift register structures.
Enhanced Fluorescence Quenching of 2‐Thiohydantoin‐Containing Conjugated Polymers: Applications for Ion Sensing
Authors: Zeng Weifeng , Yong Xue , Yang Xiaodong , Yan Yichen , Lu Xinwei , Qu Jinqing , Liu Ruiyuan
Published: June 2014

A novel poly(phenylene ethynylene) containing 2‐thiohydantoin [poly(1)] is synthesized. The addition of F− quenches the fluorescence, while the fluorescence of the solution only changes slightly upon addition of other anions, indicating the sensing ability of poly(1) toward F−. The addition of Ag+ quenches the fluorescence of the polymer, whereas the addition of other metal ions results in only slight changes to the fluorescence. Compared with its small‐molecule counterpart, the Stern–Volmer quenching constants of poly(1) toward F− and Ag+ are 165 and 105 times greater, respectively. This result indicates the amplified quenching effect of poly(1).

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Novel ANO5 homozygous microdeletion causing myalgia and unprovoked rhabdomyolysis in an Arabic man
Authors: Lahoria Rajat , Winder Thomas L. , Lui Jie , Al‐Owain Mohammed A. , Milone Margherita
Published: June 2014

Introduction: Recessive mutations in the anoctamin‐5 gene (ANO5) cause a spectrum of clinical phenotypes, including limb‐girdle muscular dystrophy (LGMD 2L), distal myopathy, and asymptomatic hyperCKemia. Methods: In this report we describe our clinical, electrophysiological, pathological, and molecular findings in a subject with anoctaminopathy‐5. Results: A 49‐year‐old Arabic man from a consanguineous family presented with a 5‐year history of myalgias, hyperCKemia and an episode of unprovoked rhabdomyolysis. Muscle biopsy showed mild myopathic changes and interstitial amyloid deposition. ANO5 analysis detected a novel homozygous deletion of approximately 11.9 kb encompassing exons 13–17, predicted to be pathogenic. Conclusions: Anoctaminopathy‐5 can manifest with a phenotype reminiscent of metabolic myopathy and should be considered as a potential cause of myalgia and myoglobinuria. Amyloid deposition in the muscle biopsy is helpful for the diagnosis. A novel homozygous ANO5 deletion was identified, suggesting that screening for common mutations may have low yield in non‐European subjects. Muscle Nerve 50: 610–613, 2014
Patient perception of pain versus observed pain behavior during a standardized electrodiagnostic test
Authors: Verson Josh , Haig Andrew J. , Sandella Danielle , Yamakawa Karen S.J. , London Zachary , Tomkins‐Lane Christy
Published: June 2014

Introduction: Clinicians often assume that observations of pain behavior are adequate for assessment of patient pain perception during procedures. This has not been tested during a standardized electrodiagnostic experience. Methods: During a prospective trial including extensive, standardized electrodiagnostic testing on persons with lumbar stenosis, vascular claudication, and asymptomatic volunteers, the subjects and an observer rated levels of pain. Results: In 60 subjects, observers significantly under‐rated pain (Visual Analog Scale 3.17 ± 2.23 vs. 4.38 ± 2.01, t = −4.577, df = 59, P < 0.001). Perceived pain during testing related to bodily pain as measured by the visual analog, McGill, Pain Disability, and Quebec scales, but not age, duration of symptoms, Tampa kinesiphobia, Center for Epidemiological Studies Depression scale, or SF‐36 health quality of life. Conclusions: Persons with worse pain syndromes may perceive more pain during testing than others. Clinicians and researchers should understand that patients may have more pain than they recognize. Muscle Nerve 51: 185–191, 2015
High angular resolution diffusion imaging with stimulated echoes: compensation and correction in experiment design and analysis
Authors: Lundell Henrik , Alexander Daniel C. , Dyrby Tim B.
Published: June 2014

Stimulated echo acquisition mode (STEAM) diffusion MRI can be advantageous over pulsed‐gradient spin‐echo (PGSE) for diffusion times that are long compared with T2. It therefore has potential for biomedical diffusion imaging applications at 7T and above where T2 is short. However, gradient pulses other than the diffusion gradients in the STEAM sequence contribute much greater diffusion weighting than in PGSE and lead to a disrupted experimental design. Here, we introduce a simple compensation to the STEAM acquisition that avoids the orientational bias and disrupted experiment design that these gradient pulses can otherwise produce. The compensation is simple to implement by adjusting the gradient vectors in the diffusion pulses of the STEAM sequence, so that the net effective gradient vector including contributions from diffusion and other gradient pulses is as the experiment intends. High angular resolution diffusion imaging (HARDI) data were acquired with and without the proposed compensation. The data were processed to derive standard diffusion tensor imaging (DTI) maps, which highlight the need for the compensation. Ignoring the other gradient pulses, a bias in DTI parameters from STEAM acquisition is found, due both to confounds in the analysis and the experiment design. Retrospectively correcting the analysis with a calculation of the full B matrix can partly correct for these confounds, but an acquisition that is compensated as proposed is needed to remove the effect entirely. © 2014 The Authors. NMR in Biomedicine published by John Wiley & Sons, Ltd.
Influence of surface modification of carbon nanotubes on interactions with polystyrene‐b‐polyisoprene‐b‐polystyrene matrix and its photo‐actuation properties
Authors: Ilčíková Markéta , Mosnáček Jaroslav , Mrlík Miroslav , Sedláček Tomáš , Csomorová Katarína , Czaniková Klaudia , Krupa Igor
Published: June 2014

The influence of various surface modification of multiwalled carbon nanotubes (MWCNT) on preferential interactions with individual phases of the linear triblock copolymer polystyrene‐b‐polyisoprene‐b‐polystyrene (SIS) and the photo‐actuation ability, reproducibility, and stability of the composite was investigated. The preferential interactions of MWCNT were achieved with covalent modification of MWCNT surface either with cholesteryl groups (MWCNT‐chol) or with short polystyrene chains (MWCNT‐PS). The specific interactions were investigated by dynamic mechanical analysis. The activation energy of glass transition of the polystyrene phase in the MWCNT‐PS/SIS composite increased significantly compared with the neat SIS matrix, while the incorporation of MWCNT‐chol resulted in selective increase of activation energy of glass transition of the polyisoprene phase. The best reproducible and stable photo‐actuation behavior was obtained during irradiation of the composite containing low content of MWCNT‐PS. Copyright © 2014 John Wiley & Sons, Ltd.
Thermodynamic description and modeling of two‐way shape‐memory effect in crosslinked semicrystalline polymers
Authors: Dolynchuk Oleksandr , Kolesov Igor , Radusch Hans‐Joachim
Published: June 2014

Recently received results have shown that crosslinked semicrystalline polymers are able to exhibit not only one‐way irreversible shape‐memory effect (SME) but also two‐way reversible SME, which is revealed as an anomalous elongation of a specimen under load during non‐isothermal crystallization and subsequent contraction during heating. Up to now, there is no well‐based physical theory, which is able to explain this phenomenon. The present study deals with theoretical explanation and description of two‐way SME in crosslinked semicrystalline polymers. The proposed approach is based on the theory of the stress‐induced crystallization but allows calculating the free energy change of a specimen deformed under constant load and cooled down below crystallization temperature at constant cooling rate, i.e. in non‐isometric and non‐isothermal conditions, respectively. The presented theory was confirmed for a covalently crosslinked high‐density polyethylene. The analysis of the free energy change performed in case of different crosslink density and deformation predicts the possible crystal morphology (extended or folded chains) and orientation of crystallites generating at cooling under load. It is shown that aforementioned anomalous elongation may be observed when the orientation of chain folds in crystals is parallel to or makes a sharp angle with the stretch direction. The stress–strain–temperature relationship derived from the free energy change was used to fit the experimental findings of the two‐way SME, which were received by the authors for crosslinked high‐density polyethylene for the first time. The fitting curves have shown well agreement with the experimental values. Copyright © 2014 John Wiley & Sons, Ltd.
A Hybrid Approach to Quantitative Software Project Scheduling within Agile Frameworks
Authors: Jahr Michael
Published: June 2014

In this article we focus on the quantitative project scheduling problem in IT companies that apply the agile management philosophy and Scrum, in particular. We combine mathematical programming with an agile project flow using a modified multi-mode resource constrained project scheduling model for software projects (MRCPSSP). The proposed approach can be used to generate schedules as benchmarks for agile development iterations. Computational experiments based on real project data indicate that this approach significantly reduces the project cycle time. The approach can be a useful addition to agile project management, especially for software projects with predefined deadlines and budgets.
Enzyme structure captures four cysteines aligned for disulfide relay
Authors: Gat Yair , Vardi‐Kilshtain Alexandra , Grossman Iris , Major Dan Thomas , Fass Deborah
Published: June 2014

Thioredoxin superfamily proteins introduce disulfide bonds into substrates, catalyze the removal of disulfides, and operate in electron relays. These functions rely on one or more dithiol/disulfide exchange reactions. The flavoenzyme quiescin sulfhydryl oxidase (QSOX), a catalyst of disulfide bond formation with an interdomain electron transfer step in its catalytic cycle, provides a unique opportunity for exploring the structural environment of enzymatic dithiol/disulfide exchange. Wild‐type Rattus norvegicus QSOX1 (RnQSOX1) was crystallized in a conformation that juxtaposes the two redox‐active di‐cysteine motifs in the enzyme, presenting the entire electron‐transfer pathway and proton‐transfer participants in their native configurations. As such a state cannot generally be enriched and stabilized for analysis, RnQSOX1 gives unprecedented insight into the functional group environments of the four cysteines involved in dithiol/disulfide exchange and provides the framework for analysis of the energetics of electron transfer in the presence of the bound flavin adenine dinucleotide cofactor. Hybrid quantum mechanics/molecular mechanics (QM/MM) free energy simulations based on the X‐ray crystal structure suggest that formation of the interdomain disulfide intermediate is highly favorable and secures the flexible enzyme in a state from which further electron transfer via the flavin can occur.
Self‐assembly of azide containing dipeptides
Authors: Yuran Sivan , Razvag Yair , Das Priyadip , Reches Meital
Published: June 2014

Functional structures and materials are formed spontaneously in nature through the process of self‐assembly. Mimicking this process in vitro will lead to the formation of new substances that would impact many areas including energy production and storage, biomaterials and implants, and drug delivery. The considerable structural diversity of peptides makes them appealing building blocks for self‐assembly in vitro. This paper describes the self‐assembly of three aromatic dipeptides containing an azide moiety: H‐Phe(4‐azido)‐Phe(4‐azido)‐OH, H‐Phe(4‐azido)‐Phe‐OH, and H‐Phe‐Phe(4‐azido)‐OH. The peptide H‐Phe(4‐azido)‐Phe(4‐azido)‐OH self‐assembled into porous spherical structures, whereas the peptides H‐Phe(4‐azido)‐Phe‐OH and H‐Phe‐Phe(4‐azido)‐OH did not form any ordered structures under the examined experimental conditions. The azido group of the peptide can serve as a photo cross‐linking agent upon irradiation with UV light. To examine the effect of this group and its activity on the self‐assembled structures, we irradiated the assemblies in solution for different time periods. Using electron microscopy, we determined that the porous spherical assemblies formed by the peptide H‐Phe(4‐azido)‐Phe(4‐azido)‐OH underwent a structural change upon irradiation. In addition, using FT‐IR, we detected the chemical change of the peptide azido group. Moreover, using indentation experiments with atomic force microscopy, we showed that the Young's modulus of the spherical assemblies increased after 20 min of irradiation with UV light. Overall, irradiating the solution of the peptide assemblies containing the azido group resulted in a change both in the morphology and mechanical properties of the peptide‐based structures. These ordered assemblies or their peptide monomer building blocks can potentially be incorporated into other peptide assemblies to generate stiffer and more stable materials. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.
Weakly nonlinear Prandtl model for simple slope flows
Authors: Grisogono Branko , Jurlina Toni , Večenaj Željko , Güttler Ivan
Published: June 2014

The Prandtl model couples, probably in the most succinct way, basic boundary‐layer dynamics and thermodynamics for pure anabatic and katabatic flows over inclined surfaces by assuming a one‐dimensional steady‐state balance between buoyancy and turbulent friction. Although the classic Prandtl model is linear, having an a priori assigned vertically constant eddy diffusivity and heat conductivity, K, in this analytic work we partly relax both of these restrictions. The first restriction is loosened by using a weakly nonlinear approach where a small parameter, ε, controls feeding of the flow‐induced potential temperature gradient back to the environmental potential temperature gradient, because the former, below the katabatic jet, can be 20–50 times stronger than the latter, background or free‐flow gradient. An appropriate range of values for ε, controlling the weak nonlinearity for pure katabatic flow, is provided. In this way, the near‐surface potential temperature gradient becomes stronger and the corresponding katabatic jet somewhat weaker (at a slightly lower height) than that in the classic Prandtl solution. The second restriction is partly relaxed by using a prescribed, gradually varying K with distance from the underlying surface, all within the usual validity of the zero‐order Wentzel–Kramers–Brillouin approximation to solve the coupled differential equations. The new model is compared with the glacier wind data from the Pasterze experiment (PASTEX‐94), Austria. Further discussion includes gradient Richardson number consideration and an application to simple anabatic flows. The model may be applied for estimation and interpretation of the wind affecting glacier mass balance and air pollution.
A Distribution‐freeCUSUMChart for Monitoring Variability of AutocorrelatedProcesses
Authors: Kim Seong‐Hee
Published: June 2014

We present a distribution‐free tabular cumulative sum chart for monitoring the variability of an autocorrelated process. A quantity known as the asymptotic variance parameter is employed as a measure of the variability, and a distribution‐free tabular cumulative sum chart is applied to variance estimates calculated from batches of nonoverlapping samples. The proposed chart is applicable to a stationary process with a general marginal distribution and a general autocorrelation structure. It also determines control limits analytically without trial‐and‐error simulations. The performance of the proposed chart is tested on stationary processes with both normal and nonnormal marginals with various autocorrelation structures. Copyright © 2014 John Wiley & Sons, Ltd.
The significance of GBA for Parkinson's disease
Authors: Brockmann Kathrin , Berg Daniela
Published: June 2014

From the first descriptions of Parkinson's disease (PD) and Gaucher's disease (GD) in the nineteenth century, it took more than 100 years to discover the link between the GBA gene and Parkinsonism. The observation that mutations in the GBA gene represent the most common genetic risk factor for PD so far only came into focus because of astute clinical observation of Gaucher patients and their families. In this review, we (i) outline how GBA was identified as a genetic risk factor for Parkinsonism, (ii) present clinical characteristics of GBA‐associated Parkinsonism, (iii) discuss possible mechanisms of the underlying pathogenesis in GBA‐associated Parkinsonism, and (iv) provide an outlook on potentially new areas of research and treatment that arise from this important discovery.
Sodium Alkyl Ether Sulfonates (SAES): Dual Anionic‐Nonionic Behavior in Synthetic Brine Having High Salinity and Hardness
Authors: Al‐Faraji Said , Al‐Maamari Rashid S. , Aoudia Mohamed
Published: June 2014

Due to the presence of non‐sulfonated residual alkyl ether (AE), sodium alkyl ether sulfonate (SAES) may exhibit clear point‐cloud point solubilization behavior in brine. Accordingly, the effect of temperature on the compatibility of iC17EOxS (x = 7 and 10), nC17EO10S, along with their analogous nonionic surfactants iC17EOxH (x = 7 and 10) and nC17EO10, in addition to iC9EO14 in brine has been investigated. Depending on their molecular structures, these surfactants exhibited concentration‐dependent clear point and cloud point solubilization behavior. The cloud point was associated with the AE component whereas the clear point was attributed to the sulfonated one. Interestingly, an increase in the cloud point of the nonionic component with respect to the corresponding nonionic AE (100 % active) was observed. Adding iC9EO14 (100 % active) to iC17EO7S (xan = 0.0–0.362) resulted in a significant decrease in the clear point of iC17EO7S from above 100 °C to below 22 °C with a concomitant increase in iC17EO7/iC9EO14 mixture cloud point from 68 °C. (xan = 0) to 72 °C (xan = 0.325). This relatively modest increase by 4 °C was attributed to the interrelationship of different competitive mechanisms, namely an increase in mixed micelle charge with increasing xan, the dehydration of OE groups via ion (SO3−)‐dipole (O → CH2) interactions, and possible shielding of SO3− groups by iC9EO14 nearby extended EO groups. To the best of our knowledge, this is the first instance where dual anionic‐nonionic solubilization behavior of SAES in brine characterized by high salinity and hardness is being reported.
The Eurasian Customs Union: An Alternative to the EU's Association Agreements?
Authors: Zahorka Hans-Jürgen , Sargsyan Ofelya
Published: June 2014

The choice for Eastern Partnership countries between the Eurasian Customs Union (CU) and the EU with its Association Agreements (AA) (including the Deep and Comprehensive Free Trade Agreements) is a political decision: the CU will never go as deep into the structure of the economy as the EU-oriented AAs. To a large extent the CU has followed the set-up of the EU, albeit under the institutionalised dominance of Russia. However, many potential CU member states are reluctant to join, especially now, in view of the Crimea crisis. One may ask whether countries are free to join or not join the CU, such freedom being a condition for regional integration.
Superlubricity on the nanometer scale
Authors: Meyer Ernst , Gnecco Enrico
Published: June 2014

The transition from atomic stick-slip to continuous sliding has been observed in a number of ways. If extended contacts are moved in different directions, so-called structural lubricity is observed when the two surface lattices are non-matching. Alternatively, a “superlubric” state of motion can be achieved if the normal force is reduced below a certain threshold, the temperature is increased, or the contact is actuated mechanically. These processes have been partially demonstrated using atomic force microscopy, and they can be theoretically understood by proper modifications of the Prandtl-Tomlinson model.
AURKA regulates JAK2–STAT3 activity in human gastric and esophageal cancers
Authors: Katsha Ahmed , Arras Janet , Soutto Mohammed , Belkhiri Abbes , El-Rifai Wael
Published: June 2014

Aurora kinase A is a frequently amplified and overexpressed gene in upper gastrointestinal adenocarcinomas (UGCs). Using in vitro cell models of UGCs, we investigated whether AURKA can regulate Signal Transducer and Activator of Transcription 3 (STAT3). Our data indicate that overexpression of AURKA in FLO‐1 and AGS cells increase STAT3 phosphorylation at the Tyr705 site, whereas AURKA genetic depletion by siRNA results in decreased phosphorylation levels of STAT3 in FLO‐1 and MKN45 cells. Immunofluorescence analysis showed that AURKA overexpression enhanced STAT3 nuclear translocation while AURKA genetic knockdown reduced the nuclear translocation of STAT3 in AGS and FLO‐1 cells, respectively. Using a luciferase reporter assay, we demonstrated that AURKA expression induces transcriptional activity of STAT3. Pharmacological inhibition of AURKA by MLN8237 reduced STAT3 phosphorylation along with down‐regulation of STAT3 pro‐survival targets, BCL2 and MCL1. Moreover, by using clonogenic cells survival assay, we showed that MLN8237 single dose treatment reduced the ability of FLO‐1 and AGS cells to form colonies. Additional experiments utilizing cell models of overexpression and knockdown of AURKA indicated that STAT3 upstream non‐receptor tyrosine kinase Janus kinase 2 (JAK2) is mediating the effect of AURKA on STAT3. The inhibition of JAK2 using JAK2‐specific inhibitor AZD1480 or siRNA knockdown, in presence of AURKA overexpression, abrogated the AURKA‐mediated STAT3 activation. These results confirm that the AURKA‐JAK2 axis is the main mechanism by which AURKA regulates STAT3 activity. In conclusion, we report, for the first time, that AURKA promotes STAT3 activity through regulating the expression and phosphorylation levels of JAK2. This highlights the importance of targeting AURKA as a therapeutic approach to treat gastric and esophageal cancers.