bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new broadband radiomagnetotelluric instrument: applications to near surface investigations
Authors: Tezkan B. , Saraev A. 
Published: August 2009

ABSTRACTA new radiomagnetotelluric (RMT) instrument has been developed that can record time series of electric and magnetic fields in the frequency range from 10 kHz to 1 MHz. Military and civilian radio stations broadcasting in this frequency range are used as transmitters. Transfer functions (e.g., apparent resistivities and phases as a function of frequency) are determined by spectral analysis using a newly developed processing software. The transfer functions presented here are the first ones ever at frequencies above 300 kHz and they can lead to a better resolution of the shallow structure. The new RMT instrument enables quick and efficient mapping of shallow structures and supports tensor measurements thereby allowing a 2D or 3D interpretation of field data. The new RMT system was tested in the laboratory and then applied successfully in the field to several environmental and engineering problems. Case studies from applications in St. Petersburg, Russia and in Uzin, Ukraine will be presented. The observed apparent resistivities and phases are reliable and they show smooth frequency dependence. The data were inverted for 2D conductivity models under the assumption that the strike direction was known beforehand.
Seismic characterization of an Alpine site
Authors: Valentina Socco Laura , Boiero Daniele , Comina Cesare , Foti Sebastiano , Wisén Roger 
Published: August 2009

ABSTRACTSite amplification of earthquake ground motion can arise from local stratigraphic and morphological conditions. In this respect, a detailed geo‐mechanical 2D model is needed, in particular for peculiar situations such as the ones in Alpine valleys. This paper reports a site characterization case history for seismic response analysis, where a combination of both body and surface wave seismic techniques has been used. In particular, it is shown that synergies and mutual cross‐checking of information lead to a reliable 2D model for site amplification studies.The evaluation of the deep structure and the location of the seismic bedrock have been obtained through seismic reflection and combined active‐passive surface wave analysis, while the shear‐wave velocity profile of the sediments has been obtained by downhole measurements and surface wave tests. Furthermore, a detailed compressional wave velocity model has been retrieved by tomographic inversion of the first arrivals picked on seismic reflection records. This model is useful for geological interpretation as well as for quality control of the other methods. Surface wave analysis has also been performed on the ground roll of the seismic reflection records. The large amount of profile oriented data has made it possible to reconstruct lateral variations of the shear‐wave velocity in the soil deposit. The final pseudo‐2D shear‐wave velocity model is the product of an innovative inversion approach, based on the integration of the Monte Carlo and laterally constrained least‐squares techniques. In the laterally constrained inversion the shear‐wave velocity profiles obtained from downhole tests and data from passive surface wave measurements have been used to constrain the inversion. This has greatly improved the final solution.This case history underlines the necessity of combining different seismic techniques to derive an accurate and reliable 2D model for site amplification studies. Through several different and independent analyses of the same seismic records, the cost effectiveness of the whole survey is optimized and a full exploitation of the information contained in the reflection seismic data set is achieved.
A multicomponent GPR survey in Marambaia Isthmus
Authors: Travassos J. M. , André S. , Musa J. E. 
Published: August 2009

ABSTRACTThis work deals with a multicomponent ground‐penetrating radar data set obtained on Quaternary unconsolidated deposits of eolian, alluvial, lacustrine and marine sands with a choice of two cross‐dipole and two co‐polar antenna configurations. The geophysical response is characterized by strong reflectors observed in both co‐ and cross‐polarized 100 MHz data sets down to a two‐way time (TWT) of 400 ns. With this data set we delineate a given horizon using its overall polarization direction, which is different from that defined by the position of the antennas and of profile direction. That horizon, whose existence was not previously known, represents a more complex situation than an isolated body, e.g., a buried metallic pipe, a situation well studied elsewhere.The polarizing horizon is characterized by linear polarization and a reasonable uniformity of an Alford rotation angle that maximizes the co‐polar responses. With the modal Alford angle we produce improved images corresponding to the two co‐polar components and a conspicuous improvement in the continuity of the reflectors across the polarizing horizon. All goes as if the antennas were oriented parallel and perpendicular to the main polarizing direction of the structure. In addition, the two co‐polar components display a good degree of independence from each other as revealed by their eigenvalues. Our results illustrate how a data set collected with less than optimal field geometry can still satisfactorily reveal the subsurface.
Frequency‐dependent attenuation and velocity characteristics of nano‐to‐micro scale, lossy, magnetite‐rich materials
Authors: Cassidy Nigel. J. 
Published: August 2009

ABSTRACTIn many situations, the magnetic properties of sub‐surface materials are often considered unimportant when compared to their ‘dielectric’ characteristics (i.e., the permittivity and conductivity). However, if significant amounts of magnetic minerals exist, such as magnetite, hematite, maghemite, etc., then the relaxation phenomena of these magnetically lossy minerals can have a significant effect on the complex apparent permittivity of the materials. In this paper, the apparent complex permittivity, attenuation and propagation characteristics of a range of nano‐to‐micro scale quartz/magnetite mixtures are investigated with the aim of determining how the lossy magnetic minerals affect the propagation of ground‐penetrating radar waves in the near‐surface environment. In addition, the investigated results are compared to popular ‘dielectric‐based’ mixing models (such as the complex refractive index model – CRIM) where the performance of the model is evaluated in terms of its appropriateness for practical situations. The results indicate that even with relatively low amounts of magnetite, the magnetic materials can have a considerable effect on the attenuation, wave propagation velocity and interface reflectivity and that the current non‐linear complex mixing models (such as CRIM) are inadequate for the description of nano‐to‐micro scale, magnetically lossy mixtures.
Numerical modelling of ground‐penetrating radar response from rough subsurface interfaces
Authors: Giannopoulos Antonios , Diamanti Nectaria 
Published: August 2009

ABSTRACTGround‐penetrating radar (GPR) modelling is employed to study the electromagnetic wave scattering that emanates from a rough subsurface interface. The numerical analysis is achieved by using a finite‐difference time‐domain numerical modelling algorithm. For the 2D GPR models, the rough interfaces are generated using both Gaussian and fractal statistics. For a given root mean square interface roughness height, we study the effect that the change in correlation length has on the incident wavefield for a randomly generated surface with a Gaussian roughness spectrum. Similarly, for an interface generated using fractal statistics, we examine the effect of fractal dimension for two different values of maximum wavenumber. For the Gaussian case, the correlation length is the most important parameter in defining the target signature. But, when fractals are used, an increase in clutter is observed as the fractal dimension increases. In addition, the clutter is more pronounced when the highest value of maximum wavenumber is used. Detection performance is evaluated by utilising 3D ground‐penetrating radar models. Comparing the 3D models with and without the presence of a rough subsurface interface, increased wavefield attenuation and strong depolarization effects were observed from a fractal subsurface terrain.
Measuring soil surface water content in irrigated areas of southern Tunisia using full‐waveform inversion of proximal GPR data
Authors: Lambot Sébastien , Slob Evert , Chavarro Diana , Lubczynski Maciek , Vereecken Harry 
Published: August 2009

ABSTRACTFull‐waveform inverse modelling of proximal ground‐penetrating radar was used to measure soil surface water content in irrigated areas of southern Tunisia. The ground‐penetrating radar system consisted of a hand held vector network analyser combined with an off‐ground monostatic horn antenna, thereby setting up an ultra wideband stepped‐frequency continuous‐wave radar. Inversion of the radar Green’s function was performed in the time‐domain, on a time window focused on the surface reflection only. Results were compared with volumetric and time‐domain reflectometry measurements, as well as with an improved version of the standard reflection coefficient method. Except for water contents close to saturation, good agreements were obtained between ground‐penetrating radar, time‐domain reflectometry and volumetric samples. Significant differences were observed when the soil electric conductivity was high and could not be neglected anymore in the inversion process. Accounting for electric conductivity provided better results. Remaining errors were attributed to the different scales of characterization dealt with in relation to the vertical variability of water content in the top few centimetres of the soil. The proposed method appears to be more practical and accurate than the standard reflection coefficient method and shows great promise for real‐time mapping of surface soil moisture at the field scale.
Association studies of −3081(A/T) polymorphism of norepinephrine transporter gene with attention deficit/hyperactivity disorder in Korean population
Authors: Joung Yoosook , Kim Chun‐Hyung , Moon Jisook , Jang Won‐Seok , Yang Jaewon , Shin Dongwon , Lee Soonyoung , Kim Kwang‐Soo 
Published: August 2009

AbstractRecent studies showing the improvement of ADHD symptoms obtained with the highly selective noradrenergic reuptake inhibitor, atomoxetine, demonstrate that the noradrenergic system plays the role of pathophysiology in this disorder. It is revealed that the norepinephrine transporter gene (SLC6A2) is a possible candidate gene directly related to ADHD. To determine possible roles of the SLC6A2 as a susceptibility gene for ADHD, we performed the genetic association study for a functional −3081(A/T) polymorphism, located in the promoter region of SLC6A2. For the present study of association between ADHD and the SLC6A2, 103 male patients with ADHD and 103 normal male controls were randomly gathered. Significant differences were found in the allele frequencies (χ2 = 5.60, P = 0.02) and the odds ratio for the allele T between the ADHD and normal subjects was 1.59 (95% CI: 1.08–2.34) suggesting that T allele is critical to make the group difference. Significant group difference was also found in AA, AT, TT genotypes (χ2 = 7.1, P = 0.02). The odds ratio for TT and AT genotypes was 4.57 (95% CI: 2.56–8.15) and 1.96 (95% CI: 0.96–3.78), respectively. Findings in the present study provided further evidence of association between ADHD and −3081(A/T) polymorphism of SLC6A2. © 2009 Wiley‐Liss, Inc.
Multifunctionality of layered fabric systems based on electrospun polyurethane/zinc oxide nanocomposite fibers
Authors: Lee Seungsin 
Published: August 2009

AbstractTo examine the feasibility of developing multifunctional textiles, layered fabric systems with electrospun polyurethane/zinc oxide nanocomposite fiber webs layered on cotton substrates were developed to impart UV‐protection and antibacterial functions. The morphology of polyurethane/zinc oxide nanocomposite fibers was examined using a field‐emission scanning electron microscope and a transmission electron microscope. UV transmission properties were assessed for layered fabric systems with various levels of electrospun web area density. Antimicrobial properties of zinc oxide nanocomposite fibers and layered fabric systems were evaluated qualitatively using the Parallel Streak method, and quantitatively by measuring the bacterial reductions of a Gram‐positive bacterium (Staphylococcus aureus) and a Gram‐negative bacterium (Klebsiella pneumoniae). A thin layer of electrospun zinc oxide nanocomposite fiber web significantly reduced the transmission of UV radiation and exhibited an ultraviolet protection factor of greater than 50, indicating excellent UV protection. Layered fabric systems with zinc oxide nanocomposite fiber webs containing 5 wt % zinc oxide exhibited over 98% reduction in both Staphylococcus aureus and Klebsiella pneumoniae. The results show that the successful imparting of multifunctionalities such as UV‐protection and antibacterial functions to cotton fabrics is achievable through simultaneous electrospinning of the polymer material with zinc oxide nanoparticles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
In Vivo Tracking of Dual‐Labeled Mesenchymal Stem Cells Homing Into the Injured Common Carotid Artery
Authors: Cao Ai Hong , Shi Hong Jian , Zhang Yu , Teng Gao Jun 
Published: August 2009

AbstractThe aim of this study is to conduct in vivo, noninvasive magnetic resonance imaging of labeled rat bone mesenchymal stem cells (BMSCs) as they home into the site of injured common carotid artery following allograft transplantation. Our study was approved by the Institutional Committee on Animal Research. Purified rat BMSCs were dual labeled with superparamagnetic iron oxide (SPIO) particle and fluorescent DiI dye, and subsequently transplanted into recipient rats injured in the left common carotid arteries. Immediately before and 3 hr, 3, 7 and 12 days after transplantation, the labeled cells were monitored in vivo using a 7T micromagnetic resonance imaging (7T micro‐MRI) scanner. The signal‐to‐noise ratios (SNRs) at the injured sites were corroborated with histological examination using Prussian blue staining and fluorescent imaging. Rat BMSCs were labeled with SPIO and DiI at 100% efficiency. When compared with the baseline level before transplantation, the SNR decreased significantly on Days 3 and 7 after injection in the experimental group (Dunnet t test, P < 0.05), whereas insignificant differences were observed after 3 hr and 12 days (Dunnet t test, P > 0.05). In the control group, no significant differences in SNR were found among different time points (ANOVA, P > 0.05). Histological analyses illustrated that red fluorescence and Prussian blue‐positive cells were mainly distributed around the lesion areas of injured common carotid arteries. Rat BMSCs can be efficiently labeled with SPIO and DiI, and the directional homing of labeled cells to the site of injured common carotid arteries after intravascular transplantation could be tracked in vivo with 7T micro‐MRI. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.
Calcaneal Tendon Regions Exhibit Different MMP‐2 Activation After Vertical Jumping and Treadmill Running
Authors: De Mello Malheiro Olga Cristina , Giacomini Camila Tateishi , Justulin Luis Antonio , Delella Flávia Karina , Dal‐Pai‐Silva Maeli , Felisbino Sérgio Luis 
Published: August 2009

AbstractIncreased activity of matrix metalloproteinases (MMPs) ‐2 and ‐9 was found in calcaneal tendon after physical training. However, little attention has been given to the distinct biomechanical and tissue structure of the calcaneal tendon's proximal and distal regions. Herein, we evaluated the effect of two types of physical activities on tendon morphology and matrix metalloproteinase activities in the proximal and distal regions of rat calcaneal tendon, separately. Adult male Wistar rats from control, water‐adapted, vertical‐jumping, and treadmill‐running groups were sacrificed after 1 or 4 days of physical exercise, 6 hr after the end of that day's exercise session. Tendons were processed for histology, morphometry, and gelatin zymography. Tendons from adapted and trained animals showed active secretory cells and increased thickness, cellularity, and blood vessel volume fraction of peritendinous sheath, but without inflammatory process. In the proximal region, both pro‐ and active MMP‐2 were increased after vertical jumping, but only pro‐MMP‐2 was increased after treadmill running. In contrast, in the distal region, both exercise types increased the activity of pro‐ and active MMP‐2, especially treadmill running, which increased the active MMP‐2 by about 11‐ and eightfold, respectively, after 1 and 4 days of training. No activity of MMP‐9 was observed in either tendon region in this study. In conclusion, distal and proximal regions of calcaneal tendon exhibit differential intensities of tissue remodeling after treadmill running or vertical jumping and MMP‐2, in the absence of inflammation, plays a major role in this adaptive response. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.
Fast dynamic response of the fermentative metabolism of Escherichia coli to aerobic and anaerobic glucose pulses
Authors: Lara Alvaro R. , Taymaz‐Nikerel Hilal , Mashego Mlawule R. , van Gulik Walter M. , Heijnen Joseph J. , Ramírez Octavio T. , van Winden Wouter A. 
Published: August 2009

AbstractThe response of Escherichia coli cells to transient exposure (step increase) in substrate concentration and anaerobiosis leading to mixed‐acid fermentation metabolism was studied in a two‐compartment bioreactor system consisting of a stirred tank reactor (STR) connected to a mini‐plug‐flow reactor (PFR: BioScope, 3.5 mL volume). Such a system can mimic the situation often encountered in large‐scale, fed‐batch bioreactors. The STR represented the zones of a large‐scale bioreactor that are far from the point of substrate addition and that can be considered as glucose limited, whereas the PFR simulated the region close to the point of substrate addition, where glucose concentration is much higher than in the rest of the bioreactor. In addition, oxygen‐poor and glucose‐rich regions can occur in large‐scale bioreactors. The response of E. coli to these large‐scale conditions was simulated by continuously pumping E. coli cells from a well stirred, glucose limited, aerated chemostat (D = 0.1 h−1) into the mini‐PFR. A glucose pulse was added at the entrance of the PFR. In the PFR, a total of 11 samples were taken in a time frame of 92 s. In one case aerobicity in the PFR was maintained in order to evaluate the effects of glucose overflow independently of oxygen limitation. Accumulation of acetate and formate was detected after E. coli cells had been exposed for only 2 s to the glucose‐rich (aerobic) region in the PFR. In the other case, the glucose pulse was also combined with anaerobiosis in the PFR. Glucose overflow combined with anaerobiosis caused the accumulation of formate, acetate, lactate, ethanol, and succinate, which were also detected as soon as 2 s after of exposure of E. coli cells to the glucose and O2 gradients. This approach (STR‐mini‐PFR) is useful for a better understanding of the fast dynamic phenomena occurring in large‐scale bioreactors and for the design of modified strains with an improved behavior under large‐scale conditions. Biotechnol. Bioeng. 2009; 104: 1153–1161. © 2009 Wiley Periodicals, Inc.
DATE analysis: A general theory of biological change applied to microarray data
Authors: Rasnick David 
Published: August 2009

AbstractIn contrast to conventional data mining, which searches for specific subsets of genes (extensive variables) to correlate with specific phenotypes, DATE analysis correlates intensive state variables calculated from the same datasets. At the heart of DATE analysis are two biological equations of state not dependent on genetic pathways. This result distinguishes DATE analysis from other bioinformatics approaches. The dimensionless state variable F quantifies the relative overall cellular activity of test cells compared to well‐chosen reference cells. The variable πi is the fold‐change in the expression of the ith gene of test cells relative to reference. It is the fraction ϕ of the genome undergoing differential expression—not the magnitude π—that controls biological change. The state variable ϕ is equivalent to the control strength of metabolic control analysis. For tractability, DATE analysis assumes a linear system of enzyme‐connected networks and exploits the small average contribution of each cellular component. This approach was validated by reproducible values of the state variables F, RNA index, and ϕ calculated from random subsets of transcript microarray data. Using published microarray data, F, RNA index, and ϕ were correlated with: (1) the blood‐feeding cycle of the malaria parasite, (2) embryonic development of the fruit fly, (3) temperature adaptation of Killifish, (4) exponential growth of cultured S. pneumoniae, and (5) human cancers. DATE analysis was applied to aCGH data from the great apes. A good example of the power of DATE analysis is its application to genomically unstable cancers, which have been refractory to data mining strategies. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
ChemInform Abstract: B‐Site Disordering in Ba3Ln2MoO9 (Ln: Ho, Er) Perovskites: A Neutron Diffraction Study.
Authors: Larregola S. A. , Alonso J. A. , Garcia Hernandez M. , Fernanez‐Diaz M. T. , Pedregosa J. C. 
Published: August 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Centric and Non‐Centric Ca3Au≈7.5Ge≈ 3.5: Electron‐Poor Derivatives of La3Al11. Syntheses, Structures, and Bonding Analyses.
Authors: Lin Qisheng , Corbett John D. 
Published: August 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Metal—Nonmetal Transition in the Sphalerite‐Type Solid Solution [ZnSnSb2]1‐x[2(InSb)]x.
Authors: Tengaa Andreas , Garcia‐Garcia F. Javier , Wu Yang , Newman N. , Haeussermann Ulrich 
Published: August 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: EuTM2Ga8 (TM: Co, Rh, Ir) — A Contribution to the Chemistry of the CeFe2Al8‐Type Compounds.
Authors: Sichevych O. , Kohout M. , Schnelle W. , Borrmann H. , Cardoso‐Gil R. , Schmidt M. , Burkhardt U. , Grin Yu. 
Published: August 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ultrasound Assisted Ambient Temperature Synthesis of Ternary Oxide AgMO2 (M: Fe, Ga).
Authors: Nagarajan R. , Tomar Nobel 
Published: August 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.