bluuebunny/crossref_metadata_2025_split huggingface dataset:
Injectivity of carbon dioxide in the St. Lawrence Platform, Quebec (Canada): A sensitivity study
Authors: Tran Ngoc T. D. , Doughty Christine , Lefebvre René , Malo Michel 
Published: November 2013

AbstractInjectivity of CO2 in the Bécancour deep saline aquifers, St. Lawrence Platform (Québec), was investigated using 2D radial numerical simulations with TOUGH2/ECO2N. In order to have an appropriate choice for the CO2 injection rate and the duration of injection, sensitivity analyses were carried out, considering different values of hydrodynamic, chemical‐petrophysical, and geometric parameters affecting CO2 injection in a brine reservoir. The parameterization analysis for capillary pressure and relative permeability models indicated large uncertainty for this case study. Simulations took into account Bécancour reservoir conditions in which the maximum pressure was limited to the fracturing pressure. The sensitivity analysis provides guidance on potential injection scenarios. To remain below fracturing pressure, intermittent 5‐year injection periods can be used, with a mass injection rate up to ∼ 20 kg/s, alternating with half‐year periods without injection. This scenario could give maximum CO2 storage in the aquifer. CO2 storage capacities in different phases were calculated versus time. This study shows that the northeastern reservoir block of the Bécancour area could host about 10 Mt CO2, which represents 15% to 50% of regional yearly CO2 emissions during about 60 and 20 years for the case of the injection formation permeability of 0.89 × 10−15 m2 and 4.17 × 10−15 m2, respectively. Finally, this modeling study will also be the basis for the design of a pilot CO2 injection test at the study site. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd
The Effect of miRNA‐122 in Regulating Fat Deposition in a Cell Line Model
Authors: Nie Yu‐Qiang , Cao Jie , Zhou Yong‐Jian , Liang Xia , Du Yan‐Lei , Wan Yu‐Jui Yvonne , Li Yu‐Yuan 
Published: November 2013

ABSTRACTAccumulating evidence supports the role of miR‐122 in fatty liver disease. We investigated miR‐122 expression in a steatotic hepatocyte model, the effect of miR‐122 over‐expression and inhibition in the pathogenesis. Human hepatic cell line L02 was induced with oleic acid to establish the steatotic hepatocyte model. Intracellular lipid content was observed with laser scanning confocal microscope (LSCM), and triglyceride content was determined with kits. Total RNA was extracted and reversely transcribed into cDNA. miR‐122 expression was measured using qRT‐PCR. Subsequently, miR‐122 mimic and miR‐122 inhibitor were transfected into steatotic hepatocytes to observe their effect on intracellular lipid content. The lipid fluorescence intensity and triglyceride content within the steatotic hepatocytes were significantly higher than those in normal control (860.01 ± 26.52 vs. 257.77 ± 29.69 and 3.47 ± 0.12 vs. 1.85 ± 0.02 at 24 h) (P < 0.01). miR‐122 expression in steatotic hepatocytes was down‐regulated compared with that in control ( value: 0.0286 ± 0.0078 vs. 0.0075 ± 0.0012) (P ≪ 0.01). After transfection, miR‐122 expression ( value) in the miR‐122 mimic group increased 2.96‐fold compared with that in control, and its lipid fluorescence intensity was significantly lower than that in control (790.92 ± 46.72 vs. 1,022.16 ± 49.66) (P < 0.01). Nevertheless, miR‐122 expression decreased 3.45‐fold in the miR‐122 inhibitor group compared with that in control, and its fluorescence intensity was significantly higher than that in control (1,386.49 ± 40.34 vs 1,022.16 ± 49.66)(P ≪ 0.01). We concluded that miR‐122 was down‐regulated in steatotic hepatocytes model. The pathogenesis of hepatocyte steatosis was enhanced by miR‐122 mimic and reduced with miR‐122 inhibitor. J. Cell. Biochem. 115: 839–846, 2014. © 2013 Wiley Periodicals, Inc.
CCN2 as a Novel Molecule Supporting Energy Metabolism of Chondrocytes
Authors: Maeda‐Uematsu Aya , Kubota Satoshi , Kawaki Harumi , Kawata Kazumi , Miyake Yoshiaki , Hattori Takako , Nishida Takashi , Moritani Norifumi , Lyons Karen M. , Iida Seiji , Takigawa Masaharu 
Published: November 2013

ABSTRACTCCN2/connective tissue growth factor (CTGF) is a unique molecule that promotes both chondrocytic differentiation and proliferation through its matricellular interaction with a number of extracellular biomolecules. This apparently contradictory functional property of CCN2 suggests its certain role in basic cellular activities such as energy metabolism, which is required for both proliferation and differentiation. Comparative metabolomic analysis of costal chondrocytes isolated from wild‐type and Ccn2‐null mice revealed overall impaired metabolism in the latter. Among the numerous metabolites analyzed, stable reduction in the intracellular level of ATP, GTP, CTP, or UTP was observed, indicating a profound role of CCN2 in energy metabolism. Particularly, the cellular level of ATP was decreased by more than 50% in the Ccn2‐null chondrocytes. The addition of recombinant CCN2 (rCCN2) to cultured Ccn2‐null chondrocytes partly redeemed the cellular ATP level attenuated by Ccn2 deletion. Next, in order to investigate the mechanistic background that mediates the reduction in ATP level in these Ccn2‐null chondrocytes, we performed transcriptome analysis. As a result, several metabolism‐associated genes were found to have been up‐regulated or down‐regulated in the mutant mice. Up‐regulation of a number of ribosomal protein genes was observed upon Ccn2 deletion, whereas a few genes required for aerobic and anaerobic ATP production were down‐regulated in the Ccn2‐null chondrocytes. Among such genes, reduction in the expression of the enolase 1 gene was of particular note. These findings uncover a novel functional role of CCN2 as a metabolic supporter in the growth‐plate chondrocytes, which is required for skeletogenesis in mammals. J. Cell. Biochem. 115: 854–865, 2014. © 2013 Wiley Periodicals, Inc.
Asymptomatic deep vein thrombosis in patients undergoing screening duplex ultrasonography
Authors: Zubrow Marc T. , Urie Jessica , Jurkovitz Claudine , Jiang Xiaozhang , Bowen James R. , DiSabatino Angela , Weintraub William 
Published: November 2013

BACKGROUNDBecause of concerns for propagating clots into pulmonary emboli by the placement of pneumatic compression boots (PCBs), the standard of care at our institution was to perform a duplex Doppler ultrasound with compression (DUSC) before applying PCBs. We sought to determine the rate of asymptomatic preexisting deep vein thrombosis (DVT) in hospitalized patients who underwent DUSC before PCB.METHODSWe evaluated consecutive patients who underwent lower extremity DUSC within 48 hours of admission. All patients were assessed for DVT risk factors using the American College of Chest Physicians' criteria (American College of Chest Physicians Conference on Antithrombotic/Thrombolytic Therapy: Evidence‐Based Guidelines, 9th Edition). A t test, Wilcoxon rank sum test, and χ2 or Fisher exact test were used to compare patients characteristics according to DVT status. Logistic regression was used to determine the importance of each risk factor on the risk of DVT.RESULTSDUSC was performed during 1136 hospitalizations; 1071 patients were included in the dataset. Of those, 19 patients (1.8%) had asymptomatic DVT and had at least 1 risk factor; 16 (84.2%) had more than 1 risk factor. The only risk factors that were statistically significant were ambulatory dysfunction and thromboembolic disease history.CONCLUSIONFew patients have asymptomatic DVT upon admission; all of these patients have at least 1 predisposing risk factor. There appears to be no need for DUSC prior to initiation of PCBs. DUSC evaluation for DVT may be of value if there is a history of previous DVT, ambulatory dysfunction, or more than 3 risk factors, as the information may change therapeutic approaches. Journal of Hospital Medicine 2014;9:19–22. © 2013 Society of Hospital Medicine
Functional and evolutionary aspects of axial stability in euarchontans and other mammals
Authors: Granatosky Michael C. , Lemelin Pierre , Chester Stephen G. B. , Pampush James D. , Schmitt Daniel 
Published: November 2013

ABSTRACTThe presence of a stable thoracolumbar region, found in many arboreal mammals, is considered advantageous for bridging and cantilevering between discontinuous branches. However, no study has directly explored the link between osteological features cited as enhancing axial stability and the frequency of cantilevering and bridging behaviors in a terminal branch environment. To fill this gap, we collected metric data on costal and vertebral morphology of primate and nonprimate mammals known to cantilever and bridge frequently and those that do not. We also quantified the frequency and duration of cantilevering and bridging behaviors using experimental setups for species that have been reported to show differences in use of small branches and back anatomy (Caluromys philander, Loris tardigradus, Monodelphis domestica, and Cheirogaleus medius). Phylogenetically corrected principal component analysis reveals that taxa employing frequent bridging and cantilevering (C. philander and lorises) also exhibit reduced intervertebral and intercostal spaces, which can serve to increase thoracolumbar stability, when compared to closely related species (M. domestica and C. medius). We observed C. philander cantilevering and bridging significantly more often than M. domestica, which never cantilevered or crossed any arboreal gaps. Although no difference in the frequency of cantilevering was observed between L. tardigradus and C. medius, the duration of cantilevering bouts was significantly greater in L. tardigradus. These data suggest that osteological features promoting axial rigidity may be part of a morpho‐behavioral complex that increases stability in mammals moving and foraging in a terminal branch environment. J. Morphol. 313–327, 2014. © 2013 Wiley Periodicals, Inc.
High resolution mass spectrometry based techniques at the crossroads of metabolic pathways
Authors: Junot Christophe , Fenaille François , Colsch Benoit , Bécher François 
Published: November 2013

AbstractThe metabolome is the set of small molecular mass compounds found in biological media, and metabolomics, which refers to as the analysis of metabolome in a given biological condition, deals with the large scale detection and quantification of metabolites in biological media. It is a data driven and multidisciplinary approach combining analytical chemistry for data acquisition, and biostatistics, informatics and biochemistry for mining and interpretation of these data. Since the middle of the 2000s, high resolution mass spectrometry is widely used in metabolomics, mainly because the detection and identification of metabolites are improved compared to low resolution instruments. As the field of HRMS is quickly and permanently evolving, the aim of this work is to review its use in different aspects of metabolomics, including data acquisition, metabolite annotation, identification and quantification. At last, we would like to show that, thanks to their versatility, HRMS instruments are the most appropriate to achieve optimal metabolome coverage, at the border of other omics fields such as lipidomics and glycomics. © 2013 Wiley Periodicals, Inc. Mass Spec Rev 33: 471–500, 2014.
Monitoring Pyrrol Polymerization Using On‐Line Conductivity Measurements and Neural Networks
Authors: Brusamarello Claiton Z. , Santos Leila M. , Amaral Monique , Barra Guilherme M. O. , Fortuny Montserrat , Santos Alexandre F. , de Araújo Pedro Henrique Hermes , Sayer Claudia 
Published: November 2013

SummaryIn this work, the chemical oxidative synthesis of polypyrrole was monitored through on‐line conductivimetry. A group of reactions was carried out at two different temperatures (5 °C and 20 °C) with varying concentrations of pyrrole and oxidant agent (FeCl3) to investigate the effect on conversion and conductivity. The relation of electrical conductivity with conversion was not straightforward. To overcome this, a neural network was proposed to predict conversion based on on‐line conductivity measurements. In this way, the neural networks entry variables were: electrical conductivity, reaction temperature, initial oxidant and pyrrole concentrations. As optimization algorithms Levenberg‐Marquardt and Descent Gradient with momentum term were evaluated. Results obtained by the neural networks based on on‐line conductivity measurements showed a good agreement with off‐line conversion data.
Production of Copolymers in a Tubular Reactors Through Nitroxide Mediated Controlled Free‐Radical Polymerization
Authors: Araujo Carolina L. , Pinto José Carlos 
Published: November 2013

SummaryThis work presents experimental results for styrene / methyl methacrylate (MMA) copolymerizations performed in a tubular reactor equipped with lateral feed lines through the nitroxide mediated controlled free‐radical mechanism. Reactions were carried out in solution with a primary feed containing a mixture of styrene, toluene, initiators and TEMPO (2,2,6,6‐tetramethyl‐1‐piperidinoxyl) and a lateral feed containing a mixture of comonomers and TEMPO. The obtained results show that copolymers can be obtained with weight average molecular weights ranging from 30 × 103 to 60 × 103 g/gmol and polydispersities ranging from 1.3 to 1.6, with monomer conversions ranging from 20 to 70 wt%. When the average residence time is manipulated, it can be observed that the average molecular weights increase linearly with time, confirming the “living” character of the reaction system.
Organoaluminum Initiators: Influence of Al Coordination on Polymerization and Product Properties
Authors: Tracht Ursula , Leiberich Ricarda , Paul Hanns‐Ingolf 
Published: November 2013

SummaryAlkyl aluminum halides are well established initiators for cationic polymerizations. They enable homogeneous polymerization processes in nonchlorinated hydrocarbon processes. Activity and polymer properties can be significantly affected by the choice of the compound used for activating the organoaluminum halide. Three examples of organoaluminum chloride based initiator systems for cationic polymerizations are presented here illustrating different stages of a workflow established for the development and optimization of such initiators and corresponding polymerization processes. Initiator formation via addition of protic compounds to organoaluminum chloride precursors is studied by multiple spectroscopic techniques, in particular IR‐spectroscopy. Differently prepared initiators are tested in lab scale batch polymerizations and continuous mini‐plant polymerizations. The influence of aluminum coordination on polymer properties like molecular weights is analyzed.
Multiobjective optimal control of a four‐body kinematic chain
Authors: Ringkamp Maik , Leyendecker Sigrid , Ober‐Blöbaum Sina 
Published: November 2013

AbstractOptimal control of mechanical systems is an active area of research. However, so far, most contributions are taking only one single objective into account, whereas for many practical problems, one is interested in optimizing several conflicting objectives at the same time. Applying singleobjective optimization to each of them leads to several trajectories each being optimal for one objective, but ignoring all others. In contrast to that, combining all objectives and using multiobjective optimization leads to a variety of trade off solutions taking all objectives into account simultaneously.We use the direct discretization method DMOCC (Discrete Mechanics and Optimal Control for Constrained systems) to approximate trajectories of the underlying optimal control problems, resulting in restricted optimization problems of high dimension. For the multiobjective part, we apply a reference point technique which successively utilizes an auxiliary distance function to gain the trade off solutions. The presented approach is illustrated by the multiobjective optimal control of a constrained multibody system. A four‐body kinematic chain is controlled in a rest to rest maneuver, for which minimal control effort and minimal required maneuver time are the conflicting objectives. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mechanical Synchronization in Dual‐Rotor Vibroactuator
Authors: Miklós Ákos , Szabó Zsolt 
Published: November 2013

AbstractIn the present work the mechanical behaviour of a dual‐rotor vibrotactor has been investigated with special attention to its stationary motions and their linear stability. After the introduction of the used mechanical model, the formulae for the stationary motions are given, and characteristic stablity charts are presented. The linear stability is investigated for uncontrolled and controlled system as well. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The benefits of training with vibration in stabilizers and postural human muscle strengthening
Authors: Fodor Rault , Vescan Sergiu Dan , Arghir Mariana 
Published: November 2013

AbstractThe mechanical vibrations have been perceived as unhealthy, although in some circunstances these may lead to a human body fortification. The trainings that use the vibrating stimulus have certain advantages to the classical trainings. Stabilizers and postural muscles are less visible, being hidden by large muscle groups and have little growth potential. For this reason most types of training does not focus on training and strengthening them. This article presents the advantages of training muscular groups of the vertebral column performed on vibrating plates. This type of training has the advantage that besides the requiring to all muscles in where the vibratory stimulus reaches, leads to an increase flexibility of joints. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Towards a Standardised Method for Visualisation of Stress Distribution at the Cartilage‐Bone Interface
Authors: Mabuma Joffrey , Markert Bernd , Ehlers Wolfgang 
Published: November 2013

AbstractThe degeneration of articular cartilage is one of the most common causes of pain and disability in middle‐aged and older people. In this context, osteoarthritis is a well‐known clinical syndrome related to cartilage degeneration. The degeneration of normal articular cartilage is not simply the result of aging and mechanical wear. Pathological loads may also increase the risk of degeneration of normal joints, and individuals who have an abnormal joint anatomy or inadequate muscle strength probably have a greater risk of degenerative joint disease.The goal of this contribution is to investigate the influence of cartilage degeneration on the stress pattern at the cartilage‐bone interface. In this connection, articular cartilage is described as a highly anisotropic and heterogeneous charged biphasic solid‐fluid aggregate in the framework of the Theory of Porous Media (TPM). After calibration of the model under physiological loading conditions, the results of a sensitivity analysis of the model parameters are presented.Realistic boundary conditions are applied on the cartilage surface of the femoral head obtained from multibody dynamics calculations. Use is made of the Hertzian contact theory for the contact pressure distribution. The applicability of a new rendition technique to visualise simulation results based on a standardised stereographic projection of the von Mises stresses along the curved cartilage‐bone interface is introduced. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Accurate calculation of stress intensity factors for strongly curved cracks applying path‐independent integrals
Authors: Judt Paul , Ricoeur Andreas 
Published: November 2013

AbstractPath‐independent contour integrals like the Jk‐integral or the Ik‐integral are beneficial to calculate accurate stress intensity factors (SIF). In order to avoid special requirements concerning crack tip meshing and with regard to an efficient calculation of contour integrals including internal boundaries and interfaces, it is beneficial to apply large contours far from the crack tip. In the case of mixed‐mode loading and strongly curved cracks, however, this usually leads to highly inaccurate results. In this paper, several methods are presented considerably improving the calculation of SIF based on Jk‐ and Ik‐integrals. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the Numerical Identification of System Properties in a Square Frame
Authors: Zenz Georg , Nachbagauer Karin , Gerstmayr Johannes , Shih Ming‐Hsiang , Yang Yeong‐Bin 
Published: November 2013

AbstractIn this paper the influencing factors of the nonlinear behavior of a highly deformable square frame are aimed to highlight and identify. Therefore, in a first step a square frame consisting of four slender members of equal length has been investigated experimentally. Subsequently to these investigations, a numerical model is set up with a beam finite element model, which is based on the absolute nodal coordinate formulation (ANCF), including geometrical and possible material nonlinearities. The influencing factors as well as the system properties are identified by using a genetic optimization algorithm. The final results show that the highly nonlinear behavior of the square frame can be reproduced accurately in case the nonlinear characteristics of the joints are taken into account carefully. The numerical model combined with the system parameter identification can be utilized for further numerical investigations of non‐standard structures undergoing large deformations. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparison of geometrically nonlinear LSFEM formulations based on different hyperelastic models
Authors: Steeger Karl , Schwarz Alexander , Schröder Jörg , Starke Gerhard , Müller Benjamin 
Published: November 2013

AbstractThis contribution deals with the solution of geometrically nonlinear elastic problems solved by the least‐squares mixed finite element method (LSFEM). The degrees of freedom (displacements and stresses) will be approximated using suitable spaces, namely W1,p with p > 4 and H(div,Ω). In order to define the stress response of the material, different hyperelastic free energy functions will be presented. The residual forms ℛI of the balance of momentum and the constitutive equation build a system of differential equations of first order. Choosing suitable weighting operators and applying L2‐norms lead to a least‐squares functional ℱ(P,u). The interpolation of the unknowns is accomplished using a standard polynomial interpolation for the displacements and vector‐valued Raviart‐Thomas functions for the approximation of the stresses. The formulations presented will be compared considering a uni‐axial spatial tension test. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determination of the derivative of the tangent stiffness matrix with respect to the load parameter
Authors: Jia Xin , Mang Herbert A. 
Published: November 2013

AbstractIn order to solve the so‐called consistently linearized eigenproblem in the frame of the Finite Element Method (FEM), the derivative of the tangent stiffness matrix $\tilde{\bf{K}}_T$ with respect to the load parameter λ needs to be calculated. In this work, three schemes for calculation of $\dot{\tilde{\bf{K}}}_T$ are presented. The first scheme is based on an analytical expression for the first derivative of e the element tangent stiffness matrix $\tilde{\bf{K}}^e_T$ with respect to λ for the special case of a co‐rotational beam element. The second one is a finite difference approach for computation of $\dot{\tilde{\bf{K}}}_T:=d\tilde{\bf{K}}_T/d\lambda$. The third one is also a finite difference approach. However, it is based on a directional derivative of $\tilde{\bf{K}}_T$. An elastic beam, subjected to a compressive axial force and a small transverse uniform load, is chosen as a numerical example. The effectiveness and the accuracy of the three schemes are compared. The third scheme is found to be not only very practical but also more effective than the two competing schemes. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)