bluuebunny/crossref_metadata_2025_split huggingface dataset:
A methodology to analyse and simulate mechanical characteristics of poly(2‐hydroxyethyl methacrylate) hydrogel
Authors: Zhao Weiwei , Lenardi Cristina , Webb Patrick , Liu Changqing , Santaniello Tommaso , Gassa Federico 
Published: November 2012

AbstractIn the present work, the mechanical properties of poly(2‐hydroxyethyl methacrylate) (PHEMA) such as ultimate strength, ultimate strain and shear modulus under compression were measured. Mathematical models for hyperelastic materials, which are often used to study rubbers or tyres and include the Mooney–Rivlin and neo‐Hookean models, were also used to theoretically analyse mechanical nonlinear behaviour of the hydrogel. The simulations based on these models were then implemented and validated by analysis with experimental data for comparison. The accuracy of simulations using the two models was subsequently assessed and discussed in order to determine which model is a feasible representation and reflection of the true behaviour of the hydrogel. This study on the mechanical behaviour of PHEMA under compression stress will ultimately serve for optimization of the design and manufacture of multilayer microfluidic devices in terms of the distribution of pressure induced in the packaging process, since the implementation of thin PHEMA hydrogel free‐standing films is required to be incorporated with harder polymeric material components, such as thermoplastics or thermoset microfabricated platforms. © 2012 Society of Chemical Industry
(Co)polymers of oligo(ethylene glycol) methacrylates—temperature‐induced aggregation in aqueous solution
Authors: Trzebicka Barbara , Szweda Dawid , Rangelov Stanislav , Kowalczuk Agnieszka , Mendrek Barbara , Utrata‐Wesołek Alicja , Dworak Andrzej 
Published: November 2012

AbstractThe synthesis and aggregation behavior of well‐defined thermosensitive (co)polymers of oligo(ethylene glycol) methacrylates (POEGMA) in aqueous solutions were investigated. The cloud points of the POEGMAs solutions were determined by turbidimetry and dynamic light scattering. For POEGMA (co)polymers the cloud point temperature (TCP) increased linearly with increasing content of more hydrophilic comonomer. The mesoglobules formed by POEGMAs in dilute aqueous solutions above TCP were studied by light scattering. The size of mesoglobules depended on the concentration and the heating procedures. The aggregates became smaller with decreasing initial concentration of polymer and increasing rates of temperature change. By selecting the proper heating and dilution procedures, the influence of the (co)polymer structure on the size of the mesoglobules could be determined. The size of the mesoglobules decreased with the length of the OEG side chains and increased with increasing content of more hydrophilic comonomer. The light scattering parameters of the mesoglobules—A2 values and shape factors
${R_{\rm g}\over R_{\rm h}}$—suggested that the hydrophilic OEG side chains placed at the periphery of the mesoglobules in direct contact with the surrounding water controlled the size of mesoglobules and their stability. Shape factors for all POEGMA mesoglobules indicated that the mesoglobules remained highly hydrated after formation. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Shear modulus determination in model hydrogels by means of elongated magnetic nanoprobes
Authors: Roeder Lisa , Bender Philipp , Tschöpe Andreas , Birringer Rainer , Schmidt Annette M. 
Published: November 2012

AbstractThe mechanical characterization of complex soft matter by quasi‐static magnetometry using nanoscopic magnetic probes is demonstrated for model hydrogels doped with two types of elongated magnetic nanoparticles. Chemically crosslinked poly(acrylamide) (PAAm) hydrogels serve as the matrix in which nickel nanorods or weakly magnetized hematite (α‐Fe2O3) ellipsoids are embedded as local probes. We investigated the swelling behavior of the ferrogels in order to verify that their equilibrium swelling degree in water is not influenced by the probes, shows a good correlation with the Frenkel–Flory–Rehner model. The proposed magnetomechanical method relies on a correlation between the shear modulus of the PAAm hydrogel matrix and the coercive fields of the corresponding isotropic ferrogels. By extending the Stoner–Wohlfarth model for single‐domain blocked magnetic particles by a term for particle rotation in an elastic matrix, information on the shear modulus of the matrix can be obtained. Comparison of the results with the expected relation from rubber elasticity theory illustrates both the general potential as well as the limits of the approach. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Chemical vapor deposition of carbon nanotube forests
Authors: Robertson J. , Zhong G. , Esconjauregui S. , Zhang C. , Fouquet M. , Hofmann S. 
Published: November 2012

AbstractWe review the growth mechanisms of vertically aligned carbon nanotube forests, in terms of what controls the growth rate and control of the catalyst lifetime. We also review the production of very high‐density forests, in terms of increasing the catalyst particle density.
Carbon nanowalls synthesis by means of atmospheric dcPECVD method
Authors: Meško Marcel , Vretenár Viliam , Kotrusz Peter , Hulman Martin , Šoltýs Ján , Skákalová Viera 
Published: November 2012

AbstractCarbon nanowalls (CNWs) were grown by atmospheric dc plasma enhanced chemical vapour deposition method. Maintaining plasma at atmospheric pressure give us possibility to synthetize CNWs at high rate. By using two different liquid carbon sources we can control CNWs density. Growth of sparsely distributed CNWs can be achieved by using ethanol, while hexane gives densely packed CNWs films.
All‐optical structure assignment of individual single‐walled carbon nanotubes from Rayleigh and Raman scattering measurements
Authors: Berciaud Stéphane , Deshpande Vikram V. , Caldwell Robert , Miyauchi Yuhei , Voisin Christophe , Kim Philip , Hone James , Heinz Tony F. 
Published: November 2012

AbstractWe present an all‐optical method for structure assignment of individual single‐walled carbon nanotubes (SWNTs) based on combined measurements of the elastically (Rayleigh) and inelastically (Raman) scattered light by individual freestanding specimens. The optical resonances of a single SWNT are identified from the Rayleigh spectra. These measurements are complemented with an independent estimation of the SWNT diameter and chiral angle from its radial breathing and G Raman modes, respectively. An assignment of the (n,m) chiral indices can thus be provided. In the most simple cases, a reliable structure assignment can be inferred from the Rayleigh spectra alone. However, we also show that SWNTs with different structures may display similar Rayleigh spectra within a given photon energy window. In these situations, Raman measurements provide unambiguous criteria for a proper structure assignment. This approach is particularly helpful in order to identify the high‐symmetry armchair and zig‐zag structures.
Independent Reading: Perspectives and Practices of Highly Effective Teachers
Authors: Sanden Sherry 
Published: November 2012

AbstractThis article summarizes conclusions reached regarding the independent reading perspectives and practices of eight elementary teachers, acknowledging the significant role teacher understandings and practices play on the literacy learning process and specifically on classroom independent reading. The commonalities in beliefs and practices regarding independent reading of these eight highly effective elementary teachers may lead to better insight for other teachers regarding the use of independent reading as a component of literacy learning. Included are practical outcomes of these findings, including independent reading events that incorporate teacher guidance, focus on student learning, and privilege student needs. Classroom implications of these findings might allow other teachers to more confidently embed independent reading in their literacy programs.
Essential role of Ubr11, but not Ubr1, as an N‐end rule ubiquitin ligase in Schizosaccharomyces pombe
Authors: Fujiwara Hidenobu , Tanaka Nobukazu , Yamashita Ichiro , Kitamura Kenji 
Published: November 2012

AbstractThe N‐end rule pathway degrades proteins bearing a destabilization‐inducing amino acid at the N‐terminus. In this proteolytic system, Ubr ubiquitin ligases recognize and ubiquitylate substrates intended for degradation. Schizosaccharomyces pombe has two similar Ubr proteins, Ubr1 and Ubr11. Both proteins have unique roles in various cellular processes, although the ubr1∆ strain shows more severe defects. However, their involvement in the N‐end rule pathway is unclear, and even the N‐end rule pathway‐dependent proteolytic activity has not been demonstrated in Sz. pombe. Here, we show that: (a) Sz. pombe has the N‐end rule pathway in which only Ubr11, but not Ubr1, is responsible; and (b) the C‐terminal fragment of the meiotic cohesin Rec8 (denoted as Rec8c) generated by separase‐mediated cleavage is an endogenous substrate of the N‐end rule pathway. Forced overexpression of stable Rec8c was deleterious in mitosis and caused a loss of the mini‐chromosome. In unperturbed mitosis without overexpression, the rate of mini‐chromosome loss was five‐fold higher in the ubr11∆ strain. Since Rec8 is normally produced in meiosis, we examined whether meiosis and sporulation were affected in the ubr11∆ strain. In unperturbed meiosis, chromosome segregation occurred almost normally and viable spores were produced in the ubr11∆ cells, irrespective of the presence of undegraded endogenous Rec8c peptides. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis and Properties of a Novel Linear Alkylated Diphenylmethane Sulfonate Gemini Surfactant
Authors: Hujun Xu , Hui Geng , Peng Kang , Dandan Chen 
Published: November 2012

AbstractThe linear alkylated diphenylmethane sulfonate (C12‐DSDM) was synthesized by a four‐step reaction with lauric acid, diphenylmethane and chlorosulfonic acid as raw materials. The structure of the final product was characterized by MS. The air–liquid surface tensions at various temperatures and salt solutions (NaCl) were measured by using the drop‐volume technique and the thermodynamic parameters of the micellization were calculated. The results show that the critical micelle concentration (CMC) and γCMC of the surfactant are 1.452 mmol L−1 and 38.49 mN m−1 at 298 K. With an increase in temperature, the CMC gradually increases, the γCMC and the maximum surface adsorption capacity Γmax decrease. The free energy of micelle formation is negative (−51.2 to −60.5 kJ mol−1).
Synthesis and Properties of Dicephalic Cationic Surfactants Containing a Quaternary Ammonium and a Guanidine Group
Authors: Song Yongbo , Li Qiuxiao , Li Yunling , Zhi Lifei 
Published: November 2012

AbstractNovel dicephalic surfactants containing a quaternary ammonium and a guanidine group were synthesized, and the effect of the alkyl chain length on micellization and antimicrobial activity were investigated. Surface tension and conductivity were applied to study the self‐aggregation of the amphiphilic molecule in aqueous solution. The results indicated that these compounds reduce the surface tension to a level of 30–36 mN/m at the air/water interface and that there is a characteristic chain length dependence of the micellization process of surfactants. The antimicrobial activity was evaluated against Gram‐negative, Gram‐positive bacteria and fungi, indicating strong antibacterial activity against tested strains.
Lipidomic Profiling of Chylomicron Triacylglycerols in Response to High Fat Meals
Authors: Bonham Maxine P. , Linderborg Kaisa M. , Dordevic Aimee , Larsen Amy E. , Nguo Kay , Weir Jacquelyn M. , Gran Petra , Luotonen Marika K. , Meikle Peter J. , Cameron‐Smith David , Kallio Heikki P. T. , Sinclair Andrew J. 
Published: November 2012

AbstractUsing lipidomic methodologies the impact that meal lipid composition and metabolic syndrome (MetS) exerts on the postprandial chylomicron triacylglycerol (TAG) response was examined. Males (9 control; 11 MetS) participated in a randomised crossover trial ingesting two high fat breakfast meals composed of either dairy‐based foods or vegetable oil‐based foods. The postprandial lipidomic molecular composition of the TAG in the chylomicron‐rich (CM) fraction was analysed with tandem mass spectrometry coupled with liquid chromatography to profile CM TAG species and targeted TAG regioisomers. Postprandial CM TAG concentrations were significantly lower after the dairy‐based foods compared with the vegetable oil‐based foods for both control and MetS subjects. The CM TAG response to the ingested meals involved both significant and differential depletion of TAG species containing shorter‐ and medium‐chain fatty acids (FA) and enrichment of TAG molecular species containing C16 and C18 saturated, monounsaturated and diunsaturated FA. Furthermore, there were significant changes in the TAG species between the food TAG and CM TAG and between the 3‐ and 5‐h postprandial samples for the CM TAG regioisomers. Unexpectedly, the postprandial CM TAG concentration and CM TAG lipidomic responses did not differ between the control and MetS subjects. Lipidomic analysing of CM TAG molecular species revealed dynamic changes in the molecular species of CM TAG during the postprandial phase suggesting either preferential CM TAG species formation and/or clearance.
A case of drug‐induced interstitial pneumonia caused by repeated exposure to bepridil
Authors: Yokoi Kensuke , Yada Hirotaka , Yoshimoto Daisuke , Hakuno Daihiko , Miyazaki Koji , Adachi Takeshi 
Published: November 2012

AbstractThe patient was a 78‐year‐old man. In August 2007, he underwent catheter ablation for atrial fibrillation after taking bepridil for 3 weeks. Soon after the ablation, he experienced frequent atrial extrasystoles and began taking bepridil again on the day he left the hospital. Six days after discharge, he was readmitted to our hospital with dyspnea and was diagnosed with acute heart failure. The patient had no recurrence of atrial fibrillation, so the administration of bepridil was stopped. His dyspnea was eased using standard therapy for heart failure and he was discharged from our hospital. In March 2011, he had a recurrence of atrial fibrillation and was readmitted to our hospital. The administration of bepridil was initiated to defibrillate the atrial fibrillation. Although bepridil stopped the atrial fibrillation by the third day, he presented with dyspnea and fever on the fourth day. A chest radiograph showed bilateral interstitial patterns that radiated from the pulmonary hilum. He was treated for acute heart failure and bacterial pneumonia, but this was ineffective. We suspected that the interstitial pneumonia was caused by bepridil. Corticosteroid therapy dramatically improved his symptoms. This was a rare case of acute drug‐induced interstitial pneumonia caused by repeated exposure to bepridil.
Are Facet Joint Bone Marrow Lesions and Other Facet Joint Features Associated With Low Back Pain? A Pilot Study
Authors: Suri Pradeep , Dharamsi Aisha S. , Gaviola Glenn , Isaac Zacharia 
Published: November 2012

ObjectiveTo determine the frequency of facet joint (FJ) bone marrow lesions, high FJ periarticular signal intensity, and FJ effusions in a convenience sample of patients with axial low back pain (LBP).DesignA cross‐sectional pilot study with retrospective data collection.SettingOutpatient spine clinics.PatientsSixty‐four adults with axial LBP scheduled to receive an FJ intra‐articular corticosteroid injection.MethodsClinical data were abstracted from the medical record by 1 physician, who was blinded to results of the magnetic resonance imaging evaluations. A musculoskeletal radiologist blinded to clinical information performed standardized assessments of the L1‐S1 spinal levels for FJ bone marrow lesions, effusions, and high periarticular signal intensity on lumbar magnetic resonance imaging, including short tau inversion recovery sequences. We calculated the frequency of these FJ features and used generalized estimating equations to examine side‐specific associations between the location of FJ features and the side on which LBP was experienced.ResultsThe sample included 64 participants with a mean (standard deviation) age of 59.9 ± 14.5 years. FJ bone marrow lesions were present in 64.1%, effusions in 70.3%, and high periarticular signal intensity in 65.6% of participants. All the features were most common at the L4‐L5 level. These FJ features showed significant associations with the side on which LBP was experienced or statistical trends toward an association, with or without adjustment for age, gender, and body mass index. The strongest side‐specific associations were seen for the number of bone marrow lesions (odds ratio [OR] 1.60 [95% confidence interval {CI},1.05‐2.43]), any FJ effusion (OR 2.23 [95% CI, 1.02‐4.85]), and the number of joints with high periarticular signal intensity (OR 1.75 [95% CI, 1.16‐2.63]).ConclusionsFJ bone marrow lesions, effusions, and high periarticular signal intensity were common in this sample of patients with axial LBP and substantially more frequent than in prior reports from unselected samples of patients with or without radicular pain. These FJ features demonstrate side‐specific associations with LBP. Further study of associations between these FJ features and LBP are warranted.
Thermally driven migration of ice-stream shear margins
Authors: Schoof Christian 
Published: November 2012

AbstractIce-stream shear margins are the lateral boundaries of narrow, fast-flowing bands of ice within an ice sheet. We develop a theory for the migration of shear margins over time driven by viscous dissipation of heat within the ice, focusing on widening of the ice stream. The location of the margin is modelled as a transition from a cold to a temperate ice-sheet bed, and simultaneously as the transition from no slip to free slip at the same location. The temperature field in the ice is affected by intense shear heating as well as by the migration velocity of the margin (i.e. by the widening rate of the ice stream); if migration is too fast, there is little time for the ice to warm up and the margin remains cold, causing the bed to freeze. This suppresses widening. Conversely, if the migration speed is too slow, the ice in the margin warms up, causing the bed on the far side of the cold–temperate transition to reach the melting point, and migration to speed up. Using a Wiener–Hopf method, we show that for a given far-field shear stress, geothermal heat flux, and ice geometry, there is a single migration velocity that balances the two effects and permits widening at a steady rate. This velocity increases with the far-field lateral shear stress imposed by the ice stream, which controls shear heating in the margin. Our results also indicate that (i) a region of temperate ice must form in the margin, and that (ii) lateral advection of ice may play a significant role in controlling migration speeds.
On the effects of finite-rate carbon/oxygen chemistry on supersonic jet instability
Authors: Massa Luca , Ravindran Prashaanth 
Published: November 2012

AbstractThe instability of high-temperature jets is studied because of its importance to the analysis of gas-turbine engine exhaust flow, shock–shock interaction and bypass transition. The focus is on fluid–chemistry coupling, where the chemical time scales are supported by both reactive and inelastic molecular processes. The former are associated with dissociation/exchange reactions, while the latter are associated with transfers of vibrational quanta. The interaction affects both the instability growth rate and acoustic feedback by sustaining thermo-acoustic damping. Resonance conditions are identified as those that yield the maximum damping against the Damköhler number. The main results of the present study are the explanation of the dichotomy between vortical and acoustic modes in relation to the thermo-acoustic damping, and the analysis of the resonance condition as it depends on the physico-chemical properties of carbon/oxygen mixtures. The ability of a mode to support thermo-acoustic damping is related to the local convective Mach number of its most amplified frequency, and thus to the phenomenon of acoustic trapping in the jet core. Regarding the second issue, carbon dioxide acts as the best damper at low jet temperatures${T}_{j} \approx 1000~\mathrm{K} $, where the vibrational relaxation is the main chemical scale, and up to${T}_{j} = 3500~\mathrm{K} $because its reactive chemistry resonates with the fluid fluctuation at a lower temperature than the dissociation of${\mathrm{O} }_{2} $. At higher temperatures, oxygen is the best damper because of the larger endothermicity of the reactions it supports.
Investigation of the Convection Term Discretization Schemes for a Force-Generated Ring-Vortex
Authors: Nouri N. M. , Motlagh S. Yekani , Navidbakhsh M. , Yasari E. 
Published: November 2012

ABSTRACTIn this paper, a model has been presented for generating a special ring vortex by applying a nonconservative force with specific distribution through the Navier-Stokes equations. Moreover, the ring's vortical pattern has been compared with the analytical and experimental results. In continuation, the diffusion, dissipation, and dispersion errors of four basic convection term interpolation schemes for the velocity and vorticity field of the vortex ring have been investigated. The simulations are performed for both the small and large time steps. Next, an appropriate discretization scheme for the convection term, and a proper order of time steps for simulating flows that contain ring vortices have been proposed. Finally, the ring vortexes generated by non-conservative force are added to the turbulent channel flow as a bubble induced vortex on carrier flow in two-phase flows, and the drag reduction due to the interaction between ring vortexes and flow vorticity field is observed.
Transient Response of Magnetostrictive Functionally Graded Material Square Plates Under Rapid Heating
Authors: Hong C. C. 
Published: November 2012

AbstractWe used the generalized differential quadrature (GDQ) method to compute the transient responses of thermal stresses and center deflection amplitude in the magnetostrictive functionally graded material (FGM) square plate under rapid heating acting at its lower surface. We obtained the GDQ solutions in the three-layer of magnetostrictive FGM plates subjected to four simply supported edges. We presented the transient responses of thermal stress and center deflection amplitude of magnetostrictive FGM plates with/without velocity feedback control, respectively, under the effects of the ratio of length to thickness, the power law index, the temperature of environment and the applied heat flux.