bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parental expectations, experiences and reactions, sense of coherence and grade of anxiety related to routine ultrasound examination with normal findings during pregnancy
Authors: Ekelin M. , Crang Svalenius E. , Larsson A‐K. , Nyberg P. , Maršál K. , Dykes A‐K. 
Published: July 2009

AbstractObjectiveTo investigate parents' expectations, experiences and reactions, sense of coherence and anxiety before and after a second‐trimester routine ultrasound examination, with normal findings.MethodsBefore and after ultrasound questionnaires including the scales parents' expectations, experiences and reactions to routine ultrasound examination (PEER‐U state of mind index), sense of coherence (SOC) and state and trait anxiety inventory (STAI), were sent to a 1‐year cohort of women and their partners. Replies received were 2183.ResultsBoth parents had significantly less worried state of mind (PEER‐U) after the examination than before. Women had a lower grade of state anxiety after than before, but for men there was no significant change. Before the ultrasound, women had a higher degree of worried state of mind, as well as a higher grade of state and trait anxiety and a lower sense of coherence, than men. The women showed a greater reduction in worried state of mind than the men after the ultrasound examination. There were no significant differences in sense of coherence before and after ultrasound.ConclusionsWomen and men are affected in their psychological well‐being in relation to a routine ultrasound examination, but their sense of coherence remains stable. Copyright © 2009 John Wiley & Sons, Ltd.
Decreased serum levels of kisspeptin in early pregnancy are associated with intra‐uterine growth restriction and pre‐eclampsia
Authors: Armstrong R. Anne , Reynolds Rebecca M. , Leask Rosemary , Shearing Catherine H. , Calder Andrew A. , Riley Simon C. 
Published: July 2009

AbstractObjectiveTo investigate whether pregnancies with development of subsequent pre‐eclampsia and intra‐uterine growth restriction are associated with altered levels of kisspeptin in maternal serum in the second trimester.Study DesignRetrospective case–control study of 16–20 week serum samples matched for duration of storage at −70 °C. Levels of kisspeptin were measured in serum from women with pregnancies with subsequent development of pre‐eclampsia (n = 57), intra‐uterine growth restriction (n = 118), and matched controls (n = 317).ResultsSerum kisspeptin levels were significantly lower in those women who subsequently developed pre‐eclampsia than in controls [median (quartile range) 1109 (449) vs 1188 (365) pg/mL, p = 0.029] and in those with intra‐uterine growth restriction [1164 (386) vs 1188 (365) pg/mL, p = 0.016].ConclusionsKisspeptin levels are lower in maternal serum in the second trimester, in pregnancies associated with placental dysfunction. The differences in kisspeptin are modest, so although not forming a single screening marker in pre‐eclampsia and intra‐uterine growth restriction, measurement of kisspeptin may be useful in combination with other markers. Understanding the role of kisspeptin in the establishment of the placenta may further our knowledge of the mechanisms underlying placental function. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of amphiphilic and thermoresponsive ABC miktoarm star terpolymer via a combination of consecutive click reactions and atom transfer radical polymerization
Authors: Li Changhua , Ge Zhishen , Liu Hewen , Liu Shiyong 
Published: July 2009

AbstractWell‐defined amphiphilic and thermoresponsive ABC miktoarm star terpolymer consisting of poly(ethylene glycol), poly(tert‐butyl methacrylate), and poly(N‐isopropylacrylamide) arms, PEG(‐b‐PtBMA)‐b‐PNIPAM, was synthesized via a combination of consecutive click reactions and atom transfer radical polymerization (ATRP). Click reaction of monoalkynyl‐terminated PEG with a trifunctional core molecule bis(2‐azidoethyl)amine, (N3)2NH, afforded difunctional PEG possessing an azido and a secondary amine moiety at the chain end, PEG‐NHN3. Next, the amidation of PEG‐NHN3 with 2‐chloropropionyl chloride led to PEG‐based ATRP macroinitiator, PEG(N3)Cl. The subsequent ATRP of N‐isopropylacrylamide (NIPAM) using PEG(N3)Cl as the macroinitiator led to PEG(N3)‐b‐PNIPAM bearing an azido moiety at the diblock junction point. Finally, well‐defined ABC miktoarm star terpolymer, PEG(‐b‐PtBMA)‐b‐PNIPAM, was prepared via the click reaction of PEG(N3)‐b‐PNIPAM with monoalkynyl‐terminated PtBMA. In aqueous solution, the obtained ABC miktoarm star terpolymer self‐assembles into micelles consisting of PtBMA cores and hybrid PEG/PNIPAM coronas, which are characterized by dynamic and static laser light scattering, and transmission electron microscopy. On heating above the phase transition temperature of PNIPAM in the hybrid corona, micelles initially formed at lower temperatures undergo further structural rearrangement and fuse into much larger aggregates solely stabilized by PEG coronas. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4001–4013, 2009
Nanostructured polymer composite nanoparticles synthesized in a single step via simultaneous ROMP and ATRP under microemulsion conditions
Authors: Airaud Cédric , Ibarboure Emmanuel , Gaillard Cédric , Héroguez Valérie 
Published: July 2009

AbstractRing‐Opening Metathesis Polymerization (ROMP) and Atom‐Transfer Radical Polymerization (ATRP) were carried out simultaneously under microemulsion conditions with 1st generation Grubbs catalyst playing a double role: ROMP initiator and ATRP controlling agent. Starting from two distinct microemulsions—one containing the monomers and the other the catalyst—well‐defined composite nanoparticles with z‐average hydrodynamic diameter smaller than 50 nm were prepared. Depending on the monomers droplet composition, homopolymers blends or graft‐copolymers were synthesized in a one‐pot, one‐step, one‐catalyst approach. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4014–4027, 2009
Thermodynamic and structural analysis of highly stabilized BPTIs by single and double mutations
Authors: Islam Mohammad Monirul , Sohya Shihori , Noguchi Keiichi , Kidokoro Shun‐ichi , Yohda Masafumi , Kuroda Yutaka 
Published: July 2009

AbstractEnhancing protein conformational stability is an important aspect of protein engineering and biotechnology. However, protein stabilization is difficult to rationalize as it often results from the small cumulative and intertwined effects of multiple mutations. Here, we analyzed the mechanisms behind a remarkable 13° stabilization produced by a single A14G and a double A14GA38V mutation in BPTI‐[5,55], a natively folded bovine pancreatic trypsin inhibitor variant. Differential scanning calorimetry analysis of three BPTI‐[5,55] variants (A14G, A38V, and A14GA38V) indicated that the A14G mutation stabilized the structure enthalpically, whereas the A38V stabilization was entropy driven. We also determined the structure of the A14GA38V mutant at 1.09 Å resolution, whereas the A38V variant did not crystallize, and we previously reported the A14G variant's structure (2ZJX). The overall structures of the A14G and A14GA38V variants were very similar to that of wild‐type BPTI, but small local structure perturbations around residues 14 and 38 strongly suggested potential factors contributing to the enthalpy stabilization. First, the A14G mutation displaced the local backbone structures around residues 14 and 38 by up to 0.7 Å, presumably increasing local van der Waals interactions. Next, this displacement produced steric clashes between neighboring residue's side‐chains in all but the variants containing the A14G mutation. Noteworthy, these clashes are not predicted from the wild type BPTI structure. These observations provide one of the first unambiguous analyses of how a subtle interplay between the sidechain and backbone structures can have a major effect on protein stability. Proteins 2009. © 2009 Wiley‐Liss, Inc.
ATP conformations and ion binding modes in the active site of anthrax edema factor: A computational analysis
Authors: Martínez Leandro , Laine Elodie , Malliavin Thérèse E. , Nilges Michael , Blondel Arnaud 
Published: July 2009

AbstractThe Edema Factor (EF), one of the virulence factors of anthrax, is an adenylyl cyclase that promotes the overproduction of cyclic‐AMP (cAMP) from ATP, and therefore perturbs cell signaling. Crystallographic structures of EF bound to ATP analogs and reaction products, cyclic‐AMP, and Pyrophosphate (PPi), revealed different substrate conformations and catalytic‐cation binding modes, one or two cations being observed in the active site. To shed light into the biological significance of these crystallographic structures, the energetics, geometry, and dynamics of the active site are analyzed using molecular dynamics simulations. The ATP conformation observed in the one‐metal‐ion structure allows stronger interactions with the catalytic ion, and ATP is more restrained than in the structure containing two Mg2+ ions. Therefore, we propose that the conformation observed in the one‐ion crystal structure is a more probable starting point for the reaction. The simulations also suggest that a C3′‐endo sugar pucker facilitates nucleophilic attack. Additionally, the two‐cation binding mode restrains the mobility of the reaction products, and thus their tendency to dissociate. Proteins 2009. © 2009 Wiley‐Liss, Inc.
Insecticidal action of mammalian galectin‐1 against diamondback moth (Plutella xylostella)
Authors: Chen Shiang Jiuun , Chen Nien‐Ting , Wang Siou‐Hua , Hsu Ju Chun , Ding Wang‐Hsien , Kuo‐Huang Ling‐Long , Huang Rong Nan 
Published: July 2009

AbstractBACKGROUND: Previous studies showed that mammalian galectin‐1 (GAL1) could interact with chitosan or chitin, one component of the peritrophic membrane (PM). This finding suggests that the PM could be a target of GAL1, which prompted the authors to explore the effect of GAL1 on larval growth and its potential mechanism.RESULTS: The development of Plutella xylostella (L.) larvae was significantly disturbed after they were fed recombinant GAL1. The histochemical structure and immunostaining pattern suggested that GAL1 treatment resulted in dose‐ and time‐dependent disruption of the microvilli and abnormalities in these epithelial cells. Ultrastructural studies showed that the PM was not present in the midgut of GAL1‐treated insects; instead, numerous bacteria were found in the lumen area. These results indicate that the protective function of the PM was disrupted by GAL1 treatment. Moreover, in vitro data showed that GAL1 interacts with chitosan/chitin in a dose‐dependent manner, and also specifically binds to the PM in vitro.CONCLUSION: In view of the fact that the carbohydrate recognition domain of GAL1 recognises the structural motif N‐acetyl lactosamine (Gal β 1–4 GlcNAc), which is similar to that of chitin (β‐1,4 N‐acetyl‐D‐glucosamine), it is proposed that the insecticidal mechanism of GAL1 involves direct binding with chitin to interfere with the structure of the PM. Copyright © 2009 Society of Chemical Industry
Magnetic and structural study of FCCγ‐Fe precipitates in Cu
Authors: Hines W. A. , Shanthakumar P. , Huang T. , Budnick J. I. , Miller R. L. , Pease D. M. , Perry D. M. 
Published: July 2009

AbstractMagnetization, X‐ray absorption fine structure, and resistivity measurements on two samples of Cu + 2.0 at% Fe are reported here. The first sample, prepared by annealing at 950 °C for 2 days followed by rapid quenching, consists of a random solid solution of Fe in Cu. The paramagnetic susceptibility follows the Curie–Weiss law 10 K ≤ T ≤ 300 K yielding an effective Fe moment of 1.9 ± 0.1 µBand a Curie temperature −2.0 ± 2.0 K. The second sample, prepared using the heat treatment above followed by a second annealing at 620 °C for 2 h, consists of face‐centered‐cubic (FCC)γ‐Fe precipitates in the Cu matrix. The formation of the Fe precipitates reduces the electronic scattering, which is reflected in the resistivity behavior. The FCC atomic short‐range order for the Fe is demonstrated with X‐ray absorption fine structure. The paramagnetic susceptibility follows the Curie–Weiss law 100 K ≤ T ≤ 300 K yielding an effective Fe moment of 1.8 ± 0.2 µBand a Curie temperature −58 ± 10 K, consistent with an antiferromagnetic (AFM) ordering. The results are discussed in the light of previous neutron investigations of the ordered magnetic structure.
Spiral structures in layered magnets
Authors: Rosenfeld E. V. , Mushnikov N. V. , Dyakin V. V. 
Published: July 2009

AbstractThe formation and stability of spiral magnetic structures in isotropic layered magnets have been studied under the assumption of a strong intralayer and several relatively weak interlayer exchange interactions. It was shown that all the possible magnetic structures can be derived from eigenvectors of a matrix of interlayer exchange integrals. No more than S different magnetic structures can be realized in a crystal that comprises S nonequivalent magnetic layers. Each of these structures can be presented as S nested simple spirals with an equal period, which turn about over the layers of the same type. However, not all of them are stable. In particular, in a two‐layer magnet (S = 2), there can exist two different double spirals but only one of them would be stable.
Realization of longitudinal pure spin currents in a four‐terminal parallel double‐quantum‐dot structure
Authors: Han Yu , Gong Weijiang , Wei Guozhu 
Published: July 2009

AbstractSpin‐dependent electron transport properties in a parallel double‐quantum‐dot structure with four terminals are theoretically investigated by means of the nonequilibrium Green function technique. When applying a local Rashba spin–orbit interaction on an individual quantum dot and introducing a finite bias between the transverse terminals, we show that in the presence of appropriate structure parameters, apparent pure spin currents come into being in the longitudinal terminals with the same amplitude and opposite polarization directions. Besides, the polarization directions of such spin currents can be efficiently inverted by the adjustment of structure parameters.
The science of atomic engineering of chalcogenide glasses
Authors: Ovshinsky Stanford 
Published: July 2009

AbstractWe briefly describe how science, invention, and technology affected and stimulated an unexplored field of material science, disordered and amorphous semiconductors, which resulted in unexpected and useful new physical, electronic, and stereochemical mechanisms. Our special focus is on chalcogenide glasses and the unique electronic devices that are made from these materials.
Amorphous selenium and its alloys from early xeroradiography to high resolution X‐ray image detectors and ultrasensitive imaging tubes
Authors: Kasap Safa , Frey Joel B. , Belev George , Tousignant Olivier , Mani Habib , Laperriere Luc , Reznik Alla , Rowlands John A. 
Published: July 2009

AbstractWe describe the progress in the science and technology of stabilized a‐Se from its early use in xerography and xeroradiography to its present use in commercial modern flat panel X‐ray imagers and ultrasensitive video tubes which utilize impact ionization of drifting holes. Both electrons and holes can drift in stabilized a‐Se, which is a distinct advantage since X‐ray photogeneration of charge carriers occurs throughout the bulk of the photoconductive layer. An a‐Se photoconductor has to be operated at high fields to ensure that the photogeneration efficiency is sufficiently large to provide reasonable X‐ray sensitivity. However, at high fields, the dark current is unacceptably large in simple metal/a‐Se/metal devices, and special multilayer device structures need to be designed. The dark current decays with time and increases with the nominal applied field. The reduction of the dark current to a tolerable level was one of the key factors that lead to the commercialization of a‐Se X‐ray detectors. We discuss the origin of the dark current, and highlight some of the current challenges in the design of next generation detectors. We also discuss the origin of impact ionization in a‐Se, and its fruitful utilization in ultrasensitive imaging devices, including the Harpicon, which are likely to lead to new high detective quantum efficiency detectors.
Local structure of amorphous GeSbTe alloys: Ge umbrella flip vs. DFT simulations
Authors: Kolobov A. V. , Fons P. , Tominaga J. 
Published: July 2009

AbstractIn this paper, we discuss the structure of amorphous Ge2Sb2Te5 derived from X‐ray absorption experiments and computer simulations. We demonstrate that despite seeming differences the proposed structures are not in contradiction and refer to the same local structure.
Photocurrent measurements in chlorine‐doped amorphous selenium
Authors: Benkhedir Mohammed L. , Mansour Mohammed , Djefaflia Fahima , Brinza Monica , Adriaenssens Guy J. 
Published: July 2009

AbstractTransient photocurrent (TPC) measurements have been carried out on evaporated a‐Se films doped with either 12.5 or 67 ppm of Cl and compared with analogous measurements on undoped a‐Se samples. The two doping levels lead to strikingly different resulting current traces. While the 12.5 ppm doping level weakens, but does not eliminate the signature of the two hole traps that are observed in the TPC signals of undoped a‐Se, no indication for those levels remains in the 67 ppm Cl‐doped samples. It is argued that suppression of the trap generated by the negative‐U D− centre agrees with the notion that they are being supplanted by doping‐induced Cl− centres. The enhanced density of D+ centres and accompanying cross‐linking of Se chains by those three‐fold coordinated sites leads in turn to the weakening and disappearance of the shallower hole trap ascribed to dihydral angle variations. Results from constant‐photocurrent and time‐of‐flight (TOF) experiments support this interpretation of the TPC observations.
Modelling thermally‐stimulated currents in disordered semiconductors
Authors: Main Charles 
Published: July 2009

AbstractWe report a computer modelling study of thermally stimulated currents in thin film semiconductors. In a multi trapping context, we examine this method as a ‘spectroscopy’ of the energy distribution of localised states. We consider so‐called ‘weak’ and ‘strong’ re‐trapping conditions, the use of non‐physical ‘effective’ attempt‐to‐escape frequencies and the effect of lifetime variation as distributions relax. We show that for strong re‐trapping in distributed states, the energy scale can be better approximated by the quasi‐Fermi level position and propose that the density of states may alternatively be computed using the easily determined derivative of the quasi‐Fermi energy with respect to temperature.
Low‐temperature amorphous silicon p–i–n photodiodes
Authors: Street Robert A. , Wong William S. , Lujan Rene 
Published: July 2009

AbstractAmorphous silicon p–i–n photodiodes are important for image sensors and solar cells. The paper describes the properties of photodiodes fabricated below 200 °C on flexible plastic substrates. The increased defect density of the low‐temperature growth increases the reverse saturation current but the forward characteristics are largely unchanged. The role of the dangling bond defects in the diode characteristics is discussed.
Applying Design of Experiments to a lift test rig
Authors: Viles Elisabeth , Tanco Martín , Isasa Inge , Arteche Unai , Sagartzazu Xabier 
Published: July 2009

AbstractAs comfort has become an important factor in the lift industry, validated lift models are currently a significant research area. In this article, we present an analysis of a lift guiding system, which transmits vibrations to the cabin and affects passengers' comfort. The project consisted of determining the most important lift guiding system factors that affect a lift's comfort. The Design of Experiments technique was chosen as the best technique available to maximize the information gathered from the experiments. In order to carry out the experiments, a lift test rig was specially constructed in order to simulate a real installation. We screened and analyzed the influence of many factors on the response with an adapted factorial fractional design. This article shows the steps carried out in planning and analyzing the experiments, putting special emphasis on the planning during every phase of the DoE application. This research project was co‐developed by a research center, a university and a well‐known Spanish lift company. Copyright © 2009 John Wiley & Sons, Ltd.
New control charts for monitoring covariance matrix with individual observations
Authors: Memar Ahmad Ostadsharif , Niaki Seyed Taghi Akhavan 
Published: July 2009

AbstractIt has recently been shown that the performance of multivariate exponentially weighted mean square and multivariate exponentially weighted moving variance charts of Huwang et al. (J. Qual. Technol. 2007; 39:258–278) in monitoring the variability of a multivariate process for individual observations is better than existing schemes. Both of these control charts monitor a distinct matrix which is an estimator of the in‐control covariance matrix. Instead of using the trace, in this paper, we propose a L1‐norm and a L2‐norm‐based distance between diagonal elements of the estimators from their expected values to design new control charts in monitoring the covariance matrix of a multivariate process. The results of simulations show that employing the new control statistics significantly improve the ability of the change detection process in the covariance matrix. Copyright © 2009 John Wiley & Sons, Ltd.
Theoretical calculation of the low laying electronic states of the molecular ion RbH+
Authors: Korek M. , Hammoud S. , Harb T. 
Published: July 2009

AbstractUsing an ab initio method, the potential energy has been calculated for the 29 lowest molecular states of symmetries 2Σ+, 2Π, 2Δ for the molecular ion RbH+. The calculation is based on nonempirical pseudopotentials and parameterized ℓ‐dependent polarization potentials. Gaussian basis sets have been used for both atoms. The spectroscopic constants for 18 electronic sates have been calculated by fitting the calculated energy values to a polynomial in terms of the internuclear distance R. Through the canonical functions approach the eigenvalue Ev, the abscissas of the corresponding turning points (Rmin and Rmax) and the rotational constants Bv have been calculated up to 24 vibrational levels for the considered bound states. The comparison of the present results with those available in literature shows a very good agreement. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010