bluuebunny/crossref_metadata_2025 huggingface dataset:
A predictive model for Arias intensity at multiple sites and consideration of spatial correlations
Authors: Foulser‐Piggott Roxane , Stafford Peter J.
Published: May 2011

Arias intensity, Ia, has been identified as an efficient intensity measure for the estimation of earthquake‐induced losses. In this paper, a new model for the prediction of Arias intensity, which incorporates nonlinear site response through the use of the average shear‐wave velocity and a heteroskedastic variance structure, is proposed. In order to estimate the effects of ground motions on spatially‐distributed systems, it is important to take into account the spatial correlation of the intensity measure. However, existing loss‐estimation models, which use Ia as an input, do not take this aspect of the ground motion into account. Therefore, the potential to model the spatial correlation of Arias intensity is also investigated. The empirical predictive model is developed using recordings from the Pacific Earthquake Engineering Research Center Next Generation of Attenuation database whereas the model for spatial correlation makes use of the well‐recorded events from this database, that is the Northridge and Chi‐Chi earthquakes. Copyright © 2011 John Wiley & Sons, Ltd.
Psychometric evaluation of the compulsive exercise test (CET) in an adolescent population: Links with eating psychopathology
Authors: Goodwin Huw , Haycraft Emma , Taranis Lorin , Meyer Caroline
Published: May 2011

Objective

Compulsive exercise describes a rigid, driven urge to exercise that has been reported in different populations, including eating disorder patients. This compulsion can develop at an early age and yet the measurement of compulsive exercise in adolescents is limited by inappropriate assessment techniques. This study aimed to psychometrically evaluate the Compulsive Exercise Test (CET) in a sample of adolescents.

Methods

The sample consisted of 1012 adolescents aged 12–14 years old, who completed the CET, the Commitment to Exercise Scale (CES), and selected subscales from the Eating Disorder Inventory‐2 (EDI‐2).

Results

Results confirmed the original five‐factor solution of the CET. The CET's concurrent validity with the CES, as well as the convergent validity with the EDI‐2, was established. The CET was not strongly related to exercise frequency.

Conclusion

The CET appears to be valid and reliable for use with adolescents. Replication with an adolescent clinical eating disorder sample is now required. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
Identification of benzothiazole derivatives and polycyclic aromatic hydrocarbons as aryl hydrocarbon receptor agonists present in tire extracts
Authors: He Guochun , Zhao Bin , Denison Michael S
Published: May 2011

Leachate from rubber tire material contains a complex mixture of chemicals previously shown to produce toxic and biological effects in aquatic organisms. The ability of these leachates to induce Ah receptor (AhR)-dependent cytochrome P4501A1 expression in fish indicated the presence of AhR active chemicals, but the responsible chemicals and their direct interaction with the AhR signaling pathway were not examined. Using a combination of AhR-based bioassays, we have demonstrated the ability of tire extract to stimulate both AhR DNA binding and AhR-dependent gene expression and confirmed that the responsible chemicals were metabolically labile. The application of CALUX (chemical-activated luciferase gene expression) cell bioassay-driven toxicant identification evaluation not only revealed that tire extract contained a variety of known AhR-active polycyclic aromatic hydrocarbons but also identified 2-methylthiobenzothiazole and 2-mercaptobenzothiazole as AhR agonists. Analysis of a structurally diverse series of benzothiazoles identified many that could directly stimulate AhR DNA binding and transiently activate the AhR signaling pathway and identified benzothiazoles as a new class of AhR agonists. In addition to these compounds, the relatively high AhR agonist activity of a large number of fractions strongly suggests that tire extract contains a large number of physiochemically diverse AhR agonists whose identities and toxicological/biological significances are unknown. Environ. Toxicol. Chem. 2011; 30:1915–1925. © 2011 SETAC
Effects of four rice paddy herbicides on algal cell viability and the relationship with population recovery
Authors: Nagai Takashi , Ishihara Satoru , Yokoyama Atsushi , Iwafune Takashi
Published: May 2011

Paddy herbicides are a high-risk concern for aquatic plants, including algae, because they easily flow out from paddy fields into rivers, with toxic effects. The effect on algal population dynamics, including population recovery after timed exposure, must be assessed. Therefore, we demonstrated concentration–response relationships of four paddy herbicides for algal growth inhibition and mortality, and the relationship between the effect on algal cell viability and population recovery following exposure. We used SYTOX Green dye assay and flow cytometry to assess cell viability of the alga Pseudokirchneriella subcapitata. Live cells could be clearly distinguished from dead cells during herbicide exposure. Our results showed that pretilachlor and quinoclamine had both algicidal and algistatic effects, whereas bensulfuron-methyl only had an algistatic effect, and pentoxazone only had an algicidal effect. Then, a population recovery test following a 72-h exposure was conducted. The algal population recovered in all tests, but the periods required for recovery differed among exposure concentrations and herbicides. The periods required for recovery were inconsistent with the dead cell ratio at the beginning of the recovery test; that is, population recovery could not be described only by cell viability. Consequently, the temporal effect of herbicides and subsequent recovery of the algal population could be described not only by the toxicity characteristics but also by toxicokinetics, such as rate of uptake, transport to the target site, and elimination of the substance from algal cells. Environ. Toxicol. Chem. 2011; 30:1898–1905. © 2011 SETAC
Effects of cyclic changes in pH and salinity on metals release from sediments
Authors: Hong Yong Seok , Kinney Kerry A , Reible Danny D
Published: May 2011

The effects of dynamic changes in pH and salinity on metal speciation and release are investigated with sediments posed in a simulated estuarine environment. The release of Zn, Cd, Mn, and Fe was studied using sediment from the Anacostia River (Washington, DC, USA) spiked with freshly precipitated amorphous cadmium sulfide to increase Cd content. The sediment was exposed to salt water (high pH, ionic strength) and freshwater (neutral pH, minimal ionic strength) continuously and alternately (to mimic tidal changes) in small microcosms over 100 d. At the conclusion of the experiments, the vertical profiles of acid volatile sulfide (AVS) and simultaneously extracted metals (SEM) as well as porewater metals and anion concentrations were characterized. Acid volatile sulfide oxidation at the sediment surface led to a commensurate increase in dissolved metal species and metal release that was strongly dependent on the changes in the overlying water characteristics. Total Cd release was substantially higher during exposure to salt water, although, as a result of complexation, predicted dissolved Cd2+ concentration in the overlying water was higher during exposure to freshwater. Total Zn release was little changed during exposure to salt water and freshwater, although the predicted dissolved Zn2+ concentration was much higher during freshwater exposures. No significant iron was released because of the rapid oxidation of ferrous iron (Fe2+) in aerobic surficial sediments and overlying water. The present study suggests that cyclic changes in pH and salinity in the overlying water can dramatically influence metal release from estuarine sediments. Environ. Toxicol. Chem. 2011; 30:1775–1784. © 2011 SETAC
An estuarine mudsnail in situ toxicity assay based on postexposure feeding
Authors: Krell Bonny , Moreira-Santos Matilde , Ribeiro Rui
Published: May 2011

In situ assays provide more realistic exposure scenarios than laboratory assays, which is particularly pertinent for estuaries because exposure conditions are difficult to simulate. Traditionally, sublethal toxicity testing endpoints, such as growth, emergence, and reproduction, imply time-delayed extrapolations from individuals to populations, communities, and ecosystems. Sublethal responses mechanistically linked to ecosystem functions have been largely neglected. Feeding is an unequivocal ecologically meaningful response because its impairment has direct and immediate effects on ecosystems, by hampering key functions such as organic matter decomposition, long before its effects at the individual level have consequences at successively higher levels of biological organization. The ultimate goal of the present study was to widen the range of ecosystem functions for estuarine quality assessments. Specifically, a short-term in situ assay based on the postexposure feeding of the mudsnail Hydrobia ulvae is presented. Methodologies to quantify precisely postexposure egestion as a surrogate of feeding were achieved. A multiple regression model from laboratory experiments was successfully applied to an in situ assay at reference (Mira River) and contaminated Portuguese estuaries (Sado River) for predicting reference results and allowing unraveling confounding factors during exposure (temperature, salinity, sediment grain size). Sensitivity comparisons of postexposure feeding with survival and growth, after Cu exposure, were carried out and used for a first preliminary appraisal of the relative consequences of ecosystem-level immediate effects. Environ. Toxicol. Chem. 2011; 30:1935–1942. © 2011 SETAC
Interaction of electrical stimulation and voluntary hand movement in SII and the cerebellum during simulated therapeutic functional electrical stimulation in healthy adults
Authors: Iftime‐Nielsen Simona Denisia , Christensen Mark Schram , Vingborg Rune Jersin , Sinkjær Thomas , Roepstorff Andreas , Grey Michael James
Published: May 2011

The therapeutic application of functional electrical stimulation (FES) has shown promising clinical results in the rehabilitation of post‐stroke hemiplegia. It appears that the effect is optimal when the patterned electrical stimulation is used in close synchrony with voluntary movement, although the neural mechanisms that underlie the clinical successes reported with therapeutic FES are unknown. One possibility is that therapeutic FES takes advantage of the sensory consequences of an internal model. Here, we investigate fMRI cortical activity when FES is combined with voluntary effort (FESVOL) and we compare this activity to that produced when FES and voluntary activity (VOL) are performed alone. FESVOL revealed greater cerebellar activity compared with FES alone and reduced activity bilaterally in secondary somatosensory areas (SII) compared with VOL alone. Reduced activity was also observed for FESVOL compared with FES alone in the angular gyrus, middle frontal gyrus and inferior frontal gyrus. These findings indicate that during the VOL condition the cerebellum predicts the sensory consequences of the movement and this reduces the subsequent activation in SII. The decreased SII activity may reflect a better match between the internal model and the actual sensory feedback. The greater cerebellar activity coupled with reduced angular gyrus activity in FESVOL compared with FES suggests that the cortex may interpret sensory information during the FES condition as an error‐like signal due to the lack of a voluntary component in the movement. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
The Less BOLD, the Wiser: Support for the latent resource hypothesis after traumatic brain injury
Authors: Medaglia John D. , Chiou Kathy S. , Slocomb Julia , Fitzpatrick Neal M. , Wardecker Britney M. , Ramanathan Deepa , Vesek Jeffrey , Good David C. , Hillary Frank G.
Published: May 2011

Previous studies of the BOLD response in the injured brain have revealed neural recruitment relative to controls during working memory tasks in several brain regions, most consistently the right prefrontal cortex and anterior cingulate cortices. We previously proposed that the recruitment observed in this literature represents auxiliary support resources, and that recruitment of PFC is not abnormal or injury specific and should reduce as novelty and challenge decrease. The current study directly tests this hypothesis in the context of practice of a working memory task. It was hypothesized that individuals with brain injury would demonstrate recruitment of previously indicated regions, behavioral improvement following task practice, and a reduction in the BOLD signal in recruited regions after practice. Individuals with traumatic brain injury and healthy controls performed the n‐back during fMRI acquisition, practiced each task out of the scanner, and returned to the scanner for additional fMRI n‐back acquisition. Statistical parametric maps demonstrated a number of regions of recruitment in the 1‐back in individuals with brain injury and a number of corresponding regions of reduced activation in individuals with brain injury following practice in both the 1‐back and 2‐back. Regions of interest demonstrated reduced activation following practice, including the anterior cingulate and right prefrontal cortices. Individuals with brain injury demonstrated modest behavioral improvements following practice. These findings suggest that neural recruitment in brain injury does not represent reorganization but a natural extension of latent mechanisms that engage transiently and are contingent upon cerebral challenge. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
The MP2‐F12 method in the TURBOMOLE program package
Authors: Bachorz Rafał A. , Bischoff Florian A. , Glöß Andreas , Hättig Christof , Höfener Sebastian , Klopper Wim , Tew David P.
Published: May 2011

A detailed description of the explicitly correlated second‐order Møller–Plesset perturbation theory (MP2‐F12) method, as implemented in the TURBOMOLE program package, is presented. The TURBOMOLE implementation makes use of density fitting, which greatly reduces the prefactor for integral evaluation. Methods are available for the treatment of ground states of open‐ and closed‐shell species, using unrestricted as well as restricted (open‐shell) Hartree–Fock reference determinants. Various methodological choices and approximations are discussed. The performance of the TURBOMOLE implementation is illustrated by example calculations of the molecules leflunomide, prednisone, methotrexate, ethylenedioxytetrafulvalene, and a cluster model for the adsorption of methanol on the zeolite H‐ZSM‐5. Various basis sets are used, including the correlation‐consistent basis sets specially optimized for explicitly correlated calculations (cc‐pVXZ‐F12). © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Receptor‐attached amphiphilic terpolymer for selective drug recognition in aqueous solutions
Authors: Loizidou Eriketi Z. , Sun Lifang , Zeinalipour‐Yazdi Constantinos
Published: May 2011

In the present work, a combination of binding studies and molecular docking were employed to demonstrate drug encapsulation and host–guest chemistry in self‐assembled micelles consisting of amphiphilic terpolymers. The terpolymer is composed of poly(3‐sulfopropyl methacrylate), as the hydrophilic component, poly(n‐dodecyl acrylate), as the hydrophobic component and poly(barbiturate receptor), as the component for drug recognition. The combined approach was tested on four model compounds from the family of barbiturates, phenobarbital, mephobarbital, secobarbital, and thiopental, chosen based on their differential hydrogen bonding capabilities. Drug encapsulation and hydrogen‐bonding based recognition within the micellar core of the receptor–terpolymer was demonstrated by micellar electrokinetic chromatography. The resulting trends in the binding affinity of the barbiturates to the receptor–terpolymer, were correlated to the trends obtained from computational docking simulations. This receptor‐modified polymeric micelle is intended to serve as a model for the design of novel, versatile, and highly selective molecular scaffolds that will provide suitable environment for host–guest chemistry and act as simplified mimics to more complex biological systems. Copyright © 2011 John Wiley & Sons, Ltd.
Magnetic resonance imaging evaluation of renal structure and function related to disease: Technical review of image acquisition, postprocessing, and mathematical modeling steps
Authors: Jones Richard A. , Votaw John R. , Salman Khalil , Sharma Puneet , Lurie C. , Kalb Bobby , Martin Diego R.
Published: May 2011

Kidney disease represents a leading cause of morbidity, with high healthcare costs. The existing methods used to evaluate renal function include measures of glomerular filtration rate (GFR), yet the clinical methods are generally inaccurate and poorly reproducible. A method that improves measures of renal function as part of a comprehensive examination that also evaluates renal structure represents an important unmet clinical need. Use of dynamic contrast‐enhanced magnetic resonance imaging (MRI) for the evaluation of renal function has been undergoing development by several groups. The methodology has been referred to as MR Urography (MRU) or MR Nephro‐urography (MRNU). MRU/MRNU shows promise for providing new insights into the evaluation of renal structure and function in relation to important disease processes, including urinary obstruction and in relation to renal transplantation. MRU/MRNU generally requires consideration of imaging acquisition technique, image postprocessing strategies, and subsequent kinetic mathematical modeling of the data in reference to specific physiological renal processes, such as renal blood flow and GFR. Here we review the specifics of proposed methods in light of the overall strengths and limitations of each of these strategies. The overall objective is to provide a roadmap for future developments in this evolving field of novel MRI applications. J. Magn. Reson. Imaging 2011;33:1270–1283. © 2011 Wiley‐Liss, Inc.
MR elastography of human lung parenchyma: Technical development, theoretical modeling and in vivo validation
Authors: Mariappan Yogesh K. , Glaser Kevin J. , Hubmayr Rolf D. , Manduca Armando , Ehman Richard L. , McGee Kiaran P.
Published: May 2011

Purpose:

To develop a novel MR‐based method for visualizing the elastic properties of human lung parenchyma in vivo and to evaluate the ability of this method to resolve differences in parenchymal stiffness at different respiration states in healthy volunteers.

Materials and Methods:

A spin‐echo MR Elastography (MRE) pulse sequence was developed to provide both high shear wave motion sensitivity and short TE for improved visualization of lung parenchyma. The improved motion sensitivity of this approach was modeled and tested with phantom experiments. In vivo testing was then performed on 10 healthy volunteers at the respiratory states of residual volume (RV) and total lung capacity (TLC).

Results:

Shear wave propagation was visualized within the lungs of all volunteers and was processed to provide parenchymal shear stiffness maps for all 10 subjects. Density corrected stiffness values at TLC (1.83 ± 0.22 kPa) were higher than those at the RV (1.14 ± 0.14 kPa) with the difference being statistically significant (P < 0.0001).

Conclusion:

1H‐based MR elastography can noninvasively measure the shear stiffness of human lung parenchyma in vivo and can quantitate the change in shear stiffness due to respiration. The values obtained were consistent with previously reported in vitro assessments of cadaver lungs. Further work is required to increase the flexibility of the current acquisition and to investigate the clinical potential of lung MRE. J. Magn. Reson. Imaging 2011;33:1351–1361. © 2011 Wiley‐Liss, Inc.
Targeted single‐shot methods for diffusion‐weighted imaging in the kidneys
Authors: Jin Ning , Deng Jie , Zhang Longjiang , Zhang Zhuoli , Lu Guangming , Omary Reed A. , Larson Andrew C.
Published: May 2011

Purpose:

To investigate the feasibility of combining the inner‐volume‐imaging (IVI) technique with single‐shot diffusion‐weighted (DW) spin‐echo echo‐planar imaging (SE‐EPI) and DW‐SPLICE (split acquisition of fast spin‐echo) sequences for renal DW imaging.

Materials and Methods:

Renal DWI was performed in 10 healthy volunteers using single‐shot DW‐SE‐EPI, DW‐SPLICE, targeted‐DW‐SE‐EPI, and targeted‐DW‐SPLICE. We compared the quantitative diffusion measurement accuracy and image quality of these targeted‐DW‐SE‐EPI and targeted DW‐SPLICE methods with conventional full field of view (FOV) DW‐SE‐EPI and DW‐SPLICE measurements in phantoms and normal volunteers.

Results:

Compared with full FOV DW‐SE‐EPI and DW‐SPLICE methods, targeted‐DW‐SE‐EPI and targeted‐DW‐SPLICE approaches produced images of superior overall quality with fewer artifacts, less distortion, and reduced spatial blurring in both phantom and volunteer studies. The apparent diffusion coefficient (ADC) values measured with each of the four methods were similar and in agreement with previously published data. There were no statistically significant differences between the ADC values and intravoxel incoherent motion (IVIM) measurements in the kidney cortex and medulla using single‐shot DW‐SE‐EPI, targeted‐DW‐EPI, and targeted‐DW‐SPLICE (P > 0.05).

Conclusion:

Compared with full‐FOV DWI methods, targeted‐DW‐SE‐EPI and targeted‐DW‐SPLICE techniques reduced image distortion and artifacts observed in the single‐shot DW‐SE‐EPI images, reduced blurring in DW‐SPLICE images, and produced comparable quantitative DW and IVIM measurements to those produced with conventional full‐FOV approaches. J. Magn. Reson. Imaging 2011;33:1517–1525. © 2011 Wiley‐Liss, Inc.
Detection of early response to temozolomide treatment in brain tumors using hyperpolarized 13C MR metabolic imaging
Authors: Park Ilwoo , Bok Robert , Ozawa Tomoko , Phillips Joanna J. , James C. David , Vigneron Daniel B. , Ronen Sabrina M. , Nelson Sarah J.
Published: May 2011

Purpose:

To demonstrate the feasibility of using DNP hyperpolarized [1‐13C]‐pyruvate to measure early response to temozolomide (TMZ) therapy using an orthotopic human glioblastoma xenograft model.

Materials and Methods:

Twenty athymic rats with intracranial implantation of human glioblastoma cells were divided into two groups: one group received an oral administration of 100 mg/kg TMZ (n = 10) and the control group received vehicle only (n = 10). 13C 3D magnetic resonance spectroscopic imaging (MRSI) data were acquired following injection of 2.5 mL (100 mM) hyperpolarized [1‐13C]‐pyruvate using a 3T scanner prior to treatment (day D0), at D1 (days from treatment) or D2.

Results:

Tumor metabolism as assessed by the ratio of lactate to pyruvate (Lac/Pyr) was significantly altered at D1 for the TMZ‐treated group but tumor volume did not show a reduction until D5 to D7. The percent change in Lac/Pyr from baseline was statistically different between the two groups at D1 and D2 (P < 0.008), while percent tumor volume was not (P > 0.2).

Conclusion:

The results from this study suggest that metabolic imaging with hyperpolarized [1‐13C]‐pyruvate may provide a unique tool that clinical neuro‐oncologists can use in the future to monitor tumor response to therapy for patients with brain tumors. J. Magn. Reson. Imaging 2011;33:1284–1290. © 2011 Wiley‐Liss, Inc.
Vascular staging of renal and adrenal malignancies with a noncontrast enhanced steady state free precession technique
Authors: Lee Christine U. , Glockner James F.
Published: May 2011

Purpose:

To compare a noncontrast enhanced balanced steady state free precession (bSSFP) MRI technique with a conventional dynamic contrast‐enhanced (DCE) three‐dimensional (3D) spoiled gradient recalled echo (SPGR) imaging in the vascular staging of renal and adrenal malignancies.

Materials and Methods:

Sixty‐three MRIs with both bSSFP and DCE acquisitions performed for initial staging of renal and adrenal malignancies were retrospectively evaluated for presence and extent of thrombus in the renal veins and inferior vena cava (IVC). Thrombus characterization was also evaluated. DCE imaging was used as the standard‐of‐reference. Histopathology was available in 46 of 63 cases as an additional external standard.

Results:

There is very good agreement between bSSFP and DCE imaging for determining the presence or absence of thrombus in the renal veins (r = 0.95; P < 0.0001) and IVC (r = 0.91; P < 0.0001). BSSFP is less successful at distinguishing bland from tumor thrombus.

Conclusion:

Noncontrast enhanced bSSFP is an acceptable alternative to DCE imaging for vascular staging of locally advanced renal/adrenal malignancies, with somewhat limited ability to distinguish bland from tumor thrombus. J. Magn. Reson. Imaging 2011;33:1406–1413. © 2011 Wiley‐Liss, Inc.
Practical signal‐to‐noise ratio quantification for sensitivity encoding: Application to coronary MR angiography
Authors: Yu Jing , Agarwal Harsh , Stuber Matthias , Schär Michael
Published: May 2011

Purpose:

To develop and evaluate a practical method for the quantification of signal‐to‐noise ratio (SNR) on coronary MR angiograms (MRA) acquired with parallel imaging.

Materials and Methods:

To quantify the spatially varying noise due to parallel imaging reconstruction, a new method has been implemented incorporating image data acquisition followed by a fast noise scan during which radiofrequency pulses, cardiac triggering and navigator gating are disabled. The performance of this method was evaluated in a phantom study where SNR measurements were compared with those of a reference standard (multiple repetitions). Subsequently, SNR of myocardium and posterior skeletal muscle was determined on in vivo human coronary MRA.

Results:

In a phantom, the SNR measured using the proposed method deviated less than 10.1% from the reference method for small geometry factors (≤2). In vivo, the noise scan for a 10 min coronary MRA acquisition was acquired in 30 s. Higher signal and lower SNR, due to spatially varying noise, were found in myocardium compared with posterior skeletal muscle.

Conclusion:

SNR quantification based on a fast noise scan is a validated and easy‐to‐use method when applied to three‐dimensional coronary MRA obtained with parallel imaging as long as the geometry factor remains low. J. Magn. Reson. Imaging 2011;33:1330–1340. © 2011 Wiley‐Liss, Inc.
Preclinical use of longitudinal MRI for screening the efficacy of s‐nitrosoglutathione in treating spinal cord injury
Authors: Chou Peter Cheng‐te , Shunmugavel Anandakumar , Sayed Hanaa El , Desouki Mohamed Mokhtar , Nguyen Shaun A. , Khan Mushfiquddin , Singh Inderjit , Bilgen Mehmet
Published: May 2011

Purpose:

To evaluate the therapeutic efficacy of S‐nitrosoglutathione (GSNO) in spinal cord injury (SCI) using in vivo MRI in combination with neuorobehavioral testing and postmortem tissue analysis.

Materials and Methods:

Sixteen female rats were mildly injured at the vertebral T10 level and randomized into control (n = 8) and GSNO‐treatment (n = 8) groups. GSNO was delivered at 0.05 mg/kg dose in saline by means of tail vein at 1 hr postinjury and then given orally on the following days. On postinjury days 1, 3, 7, and 28, the rats were tested behaviorally, then scanned using sagittal T2‐weighted MRI for the quantification of lesion, edema, and hemorrhagic regions at the injury site. Excised cords were analyzed using histology and immunohistochemistry.

Results:

Treatment with GSNO was feasible in rats with SCI. On the average, the GSNO group at each scan day 1, 3, 7, and 28 exhibited better functional recovery as indicated by the behavioral performance of 52%, 33%, 19%, and 18%, and had smaller lesions of −4%, −16%, −20%, and −17% compared with the controls, respectively. Edema trend was parallel to the lesion volumes in both groups. Ex vivo data demonstrated that GSNO plays a role in neuronal tissue preservation and sparing.

Conclusion:

The data collectively provided the preliminary evidence that the injured rats responded favorably to GSNO treatment. Longitudinal MRI provides critical quantitative information regarding the changes in lesion properties, which helps evaluating the efficacy of an exogenous intervention in SCI. J. Magn. Reson. Imaging 2011;33:1301–1311. © 2011 Wiley‐Liss, Inc.
Comparative study of standard space and real space analysis of quantitative MR brain data
Authors: Aribisala Benjamin S. , He Jiabao , Blamire Andrew M.
Published: May 2011

Purpose:

To compare the robustness of region of interest (ROI) analysis of magnetic resonance imaging (MRI) brain data in real space with analysis in standard space and to test the hypothesis that standard space image analysis introduces more partial volume effect errors compared to analysis of the same dataset in real space.

Materials and Methods:

Twenty healthy adults with no history or evidence of neurological diseases were recruited; high‐resolution T1‐weighted, quantitative T1, and B0 field‐map measurements were collected. Algorithms were implemented to perform analysis in real and standard space and used to apply a simple standard ROI template to quantitative T1 datasets. Regional relaxation values and histograms for both gray and white matter tissues classes were then extracted and compared.

Results:

Regional mean T1 values for both gray and white matter were significantly lower using real space compared to standard space analysis. Additionally, regional T1 histograms were more compact in real space, with smaller right‐sided tails indicating lower partial volume errors compared to standard space analysis.

Conclusion:

Standard space analysis of quantitative MRI brain data introduces more partial volume effect errors biasing the analysis of quantitative data compared to analysis of the same dataset in real space. J. Magn. Reson. Imaging 2011;33:1503–1509. © 2011 Wiley‐Liss, Inc.
Impact of outliers on diffusion tensor and Q‐ball imaging: Clinical implications and correction strategies
Authors: Sharman Michael A. , Cohen‐Adad Julien , Descoteaux Maxime , Messé Arnaud , Benali Habib , Lehericy Stéphane
Published: May 2011

Purpose:

To measure the impact of corrupted images often found to occur in diffusion‐weighted magnetic resonance imaging (DW‐MRI). To propose a robust method for the correction of outliers, applicable to diffusion tensor imaging (DTI) and q‐ball imaging (QBI).

Materials and Methods:

Monte Carlo simulations were carried out to measure the impact of outliers on DTI and QBI reconstruction in a single voxel. Methods to correct outliers based on q‐space interpolation and direction removal were then implemented and validated in real image data.

Results:

Corruption in a single voxel led to clear variations in DTI and QBI metrics. In real data, the method of q‐space interpolation was successful in identifying corrupted voxels and restoring them to values consistent with those of uncorrupted images.

Conclusion:

For images containing few gradient directions, where outlier removal was either impossible due to limited volumes or resulted in large changes in DTI/QBI metrics, q‐space interpolation proved to be the method of choice for image restoration. A simple decision support system is proposed to assist clinicians in the correction of their corrupted DW data. J. Magn. Reson. Imaging 2011;33:1491–1502. © 2011 Wiley‐Liss, Inc.
Synoptic environments favourable for urban convection in Atlanta, Georgia
Authors: Bentley Mace L. , Stallins J. Anthony , Ashley Walker S.
Published: May 2011

An examination of synoptic environments conducive to urban thunderstorm development surrounding Atlanta, Georgia, was conducted. Synoptic environmental characteristics were evaluated utilising regional analyses of heights, winds, temperature, and moisture characteristics as well as several thermodynamic variables. A flexible beta cluster analysis was used in order to identify disparate groupings of common synoptic and thermodynamic environments. These groupings were then further analysed through the production of synoptic composites, radar, and lightning distributions. Although the analysis stratified the data by days with weak synoptic flow and maritime tropical airmass characteristics, enough variation existed within the synoptic and thermodynamically grouped parameters to identify four distinct environments present during urban thunderstorms. Environments exhibiting moderate thermodynamic instability were found to produce the highest flash rates and most frequent composite reflectivity days. Copyright © 2011 Royal Meteorological Society
Quasi‐quadrennial variability in European precipitation
Authors: Álvarez‐García Francisco J. , Lorente‐Lorente Pilar M. , OrtizBevia María J.
Published: May 2011

The variability of seasonal precipitation anomalies over Europe displays significant spectral peaks at quasi‐quadrennial periods, appearing in power spectra of the two leading principal components of the field. Band‐pass filtering of these time series reveals the presence of two different signals within the quadrennial band, each associated to distinct precipitation, sea level pressure (SLP) and sea surface temperature (SST) patterns, obtained here by means of linear regression and composite analysis. One of the quadrennial components seems to be connected with the impact of El Niño‐Southern Oscillation (ENSO) over Europe, that leads to anomalous SLP over the North Sea, southwestern Scandinavia and central Europe, along with precipitation anomalies of the same sign in a wide band extending from the British Isles into eastern Europe, fringed by anomalies of the opposite sign along the Norwegian coast and in the western Mediterranean area. The other quadrennial component bears no correlation with the Tropical Pacific SST anomalies, and seems connected with SST anomalies in the equatorial Atlantic, and in the Mediterranean, North and Norwegian Seas. The precipitation anomalies feature a contrast between the northern and southern regions of Europe akin to that associated with the North Atlantic Oscillation (NAO). The SLP pattern resembles the NAO structure, but with a marked eastward shift of its two centres of action towards central Europe and the Barents Sea, respectively. Copyright © 2011 Royal Meteorological Society
Decadal variability in springtime snow over Eurasia: Relation with circulation and possible influence on springtime rainfall over China
Authors: Zuo Zhiyan , Zhang Renhe , Wu Bingyi , Rong Xinyao
Published: May 2011

The relationship between decadal variability in springtime (March–May) snow water equivalent (SWE) over Eurasia and springtime rainfall over China is investigated for 1979–2004 using satellite‐observed SWE, rainfall observations from 595 stations, and NCEP/NCAR reanalysis data. Decreasing springtime SWE in Eurasia corresponded to reduced springtime rainfall over southeastern and northeast China, and more rainfall over southwestern and northwestern China. This relationship was supported by the feedback effect of snow in high‐latitude areas to changes in background atmospheric circulation.

A decadal shift in springtime Eurasian SWE occurred in the late 1980s, marked by a change from persistent positive phases in 1979–1987 to frequent negative phases. The reduction in Eurasian SWE resulted in reduced upward surface heat flux to the atmosphere and, thereby, higher boundary layer height due to increased downward heat flux into subsurface soil. These changes resulted in reduced upward and poleward wave flux activity, which corresponded to anomalous negative heights/pressures in the Arctic and anomalous positive heights/pressures in mid‐latitude regions from the upper‐level troposphere to the surface. There was an anomalous anti‐cyclonic circulation over Siberia and the western Pacific subtropical high was weakened, accompanied by an anomalous northerly in eastern China and westerly in northwestern China. The anomalous northerly resulted in reduced water vapour convergence in southeastern and northeast China, and reduced water vapour export for southwestern and northwestern China. Thus, negative rainfall anomalies developed over southeastern and northeast China, and positive rainfall anomalies appeared over southwestern and northwestern China. Copyright © 2011 Royal Meteorological Society
Late 20th‐century trends in Iowa watersheds: an investigation of observed and modelled hydrologic storages and fluxes in heavily managed landscapes
Authors: Steffens Kayla J. , Franz K. J.
Published: May 2011

Many climate change studies have shown that streamflow has been changing across the US over the last century. However, there are fewer studies examining trends in hydrologic variables such as soil moisture and snow, which tend to be poorly observed in some regions. Hydrologic models can be applied to understand changes in processes with limited spatial or temporal observational records. However, the application of hydrologic models to long time periods can be complicated by human influences on the hydrologic cycle. In this study, we explore hydrologic changes and the applicability of a commonly used hydrologic modelling system for climate change analysis in a heavily managed landscape. Historical streamflow observations and model‐derived time series of subsurface storage, frozen ground, and snow cover were analysed for 10 Iowa watersheds. The modelled data were generated using precipitation and temperature data spanning 1948–2003 as inputs to common hydrologic prediction models. Time series were tested for trends and significance using the Mann‐Kendall (MK) test with the Trend‐Free Pre‐Whitening procedure at a p = 0.1 significance level. Plots of 10‐year running averages were also examined. Significantly increasing trends in mean daily discharge and the number of high‐flow days were found for several watersheds. Increasing monthly subsurface water content was observed throughout the year in most basins, and was greatest during the winter. The number of modelled frozen‐ground days declined at all sites. Three different model calibration periods were tested and found to reproduce the general upward trend observed in the daily mean discharge. However, the model results varied from the observed in both magnitude and the number of sites identified to have MK trends. Additional functionality that considers land management and land cover change may make the models applied here more accurate for studying climate change impacts in regions such as Iowa. Copyright © 2011 Royal Meteorological Society
Synthesis and Characterization of Cytocompatible Sulfonated Polyanilines
Authors: Yang Yanyin , Min Yong , Wu Jen‐Chieh , Hansford Derek J. , Feinberg Stephen E. , Epstein Arthur J.
Published: May 2011

We report here that by good design, polyaniline (PANI) can be cytocompatible and formed into usable scaffolds for bio‐medical applications. By adjusting the ratio of two monomers, aniline (AN) and metanilic acid (MA), a series of copolymers with different sulfonation degrees have been synthesized. Four‐probe conductivity measurements showed that as the sulfonation degree increased, the conductivity decreased. XPS analysis was used to determine the sulfur/nitrogen ratio. In vitro cell culture study was conducted with human osteosarcoma (HOS) cells. Microscopic observation did not show abnormal cellular behavior when sulfonated polyaniline (SPAN) was put in direct contact with HOS cells. Cells growing on the non‐transparent dark green SPAN films were observed with fluorescence by laser scanning cytometry (LSC). In proliferation studies more than 70% of cells were found viable on SPAN compared to 88% for poly(L‐lactic acid) with the number of cells growing on glass as a control, indicating generally good biocompatibility. We expect these polymers would have great potential in biological applications of conducting polymers as we determine that a variety of physical and chemical properties can be controlled through synthesis.

magnified image
A tunable dual band notch on a UWB printed slot monopole antenna by using open circuit stubs
Authors: Nezhad Sajad Mohammad Ali , Dadashzadeh Gholamreza , Foudazi Ali
Published: May 2011

A new printed wide slot antenna with single‐ and dual‐band notch behavior is presented. The base of antenna is a simple fork‐shaped radiating patch, which covers the ultra‐wideband (UWB) frequency range. By using additional protrudent open circuit stubs on the base patch, multiband notch behavior is obtained. Effects of varying the added stubs parameters on the antenna performance show that the center frequency of band rejections can be finely tuned. The proposed dual‐band notch antenna covers 2.4–10 GHz with two bands rejection for WiMAX (3.3–3.9 GHz) and WLAN (5.7–6 GHz) bands. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26095
Surface‐mount WWAN monopole slot antenna for mobile handset
Authors: Wong Kin‐Lu , Lin Po‐Wei
Published: May 2011

A surface‐mount monopole slot antenna with a small volume of 13 × 28.5 × 2.2 mm3 for penta‐band wireless wide area network operation in the mobile handset is presented.The antenna is to be surface‐mounted at a rectangular notch of size 13 × 28.5 mm2 near the bottom edge of the system ground plane. When surface‐mounted, the antenna is closely integrated with surrounding system ground plane on the main circuit board of the handset. The antenna can provide two wide operating bands of 824–960 and 1710–2170 MHz to respectively cover the GSM850/900 and GSM1800/1900/UMTS operations. The surface‐mount antenna mainly comprises a monopole slot of width 4 mm and length 50 mm, which is bent to have a compact size and is fed by a microstrip feedline. Both the monopole slot and microstrip feedline are printed on two opposite surfaces of a dielectric substrate, which is bent into an inverted‐U shape for surface‐mounting on the circuit board of the handset. Details of the proposed antenna are described, and results of the antenna including its specific absorption rate values are presented and discussed. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26096
Design and experimental evaluation of a composite strain rosette using fiber Bragg grating
Authors: Ramos C. A. , de Oliveira R. , Marques A.T. , Frazão O.
Published: May 2011

The purpose of this study is to design a composite strain rosette using embedded fiber Bragg grating (FBG) sensors. Those strain rosettes are meant to be used as alternative to the conventional electric rosettes in structural health monitoring applications being glued at the structure surface. A thin (400 μm) and flexible weaved carbon fiber reinforced plastic (CFRP) composite rosette is proposed. The three FBG sensors were written in a single optical fiber. Special care was devoted to the embedding process of the optical fiber sensors in the weaved composite plate in order to avoid significant alteration of the light reflected back by the FBG. The strain response of the composite rosette was compared to electrical strain gage's when applied at the surface of an aluminium sample submitted to tension, flexion and to dynamic strain. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26098
Bandpass filter with wide stopband using broadside‐coupled microstrip T‐stub/DGS cell
Authors: Luo Xun , Ma Jian‐Guo , Li Erping
Published: May 2011

A bandpass filter with wide stopband is proposed using the novel broadside‐coupled microstrip T‐stub/defected ground structure cells in this letter.The resonance of the proposed cell is finely adjusted. Besides, these cells with a proper coupled‐structure (i.e., interdigital coupled scheme) can achieve high selectivity only around the resonance, which leads to wide stopband operation. The measured filter operated at 2.2 GHz (i.e., center frequency f0) exhibits a wide stopband up to 9.1 f0 with a good rejection level greater than 30.5 dB. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26101
Design of printed multistrip monopole antenna for UWB applications
Authors: Shambavi K. , Alex Zachariah C.
Published: May 2011

Design and performance measures of a printed multistrip monopole antenna for ultra‐wideband application are presented. The proposed antenna consists of six quarter wavelength strips of different resonant frequency combined in a manner to provide wide bandwidth and omnidirectional pattern. It operates in the frequency range 2.22∼11.67 GHz with impedance bandwidth (VSWR < 2) of 9.45 GHz and maximum gain of 6.07 dBi. The radiation pattern is nearly omnidirectional in the Azimuthal plane and bidirectional in the elevation plane and the consistency of the radiation pattern exists for almost all frequency in the operating band. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26103
Comparative study of slot loaded rectangular microstrip antenna for impedance bandwidth and its verification
Authors: Sameena N. M. , Mulgi S. N.
Published: May 2011

This article presents the comparative study of impedance bandwidth of rectangular microstrip antenna comprising different shaped slots on the patch. It is found that the rectangular slot on the center of patch is effective for the enhancement of impedance bandwidth in comparison with elliptical and circular shaped slots. Further, if the rectangular slot is shifted from the center of the patch, antenna provides dual bands. Later, if the G‐shaped slot is constructed using rectangular slots, antenna gives maximum impedance bandwidth of 78.07% and gain 3 dB. The experimental impedance bandwidth of proposed antennas is verified theoretically. In all the cases, the radiation pattern is found to be broadside in nature. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26105
Bandstop filters with variable upper passbands using embedded line, spurline, and conventional microstrip
Authors: Huse Ching‐Wen , Tsai Yi‐Hsien , Wu Chang‐Yu
Published: May 2011

Three planar structures including embedded line, spurline, and conventional microstrip are used to implement bandstop filters and their performances of bandwidth, center frequency and higher‐order stopbands are studied in the discrete‐time domain. A two‐section, equal‐length stub is presented to change the ratio of the next higher‐order harmonic frequency to the fundamental frequency. A filter having upper passband widths of up to nine times the fundamental stopband central frequency can be obtained by using conventional microstrip. A higher‐order bandstop filter is implemented with hybrid embedded line, spurline, and conventional microstrip to show the validity of the design method. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26107
Second iteration fractal Koch planar log periodic antenna design
Authors: Rahim M. K. A. , Karim M. N. A. , Zubir F. , Ayop O. , Samsuri N. A.
Published: May 2011

In this article, the design of log periodic fractal Koch antenna using the second iteration has been developed for ultra high frequency band applications. The ability to reduce the size as maintaining the performances of the antenna such as input return loss and radiation patterns brings fractal Koch and becomes enticing among researchers. The design of the log periodic fractal Koch antenna has been elaborated in this article. The computer simulation technology software has been used to analyze the performances of the designed antenna. This has been compared between simulation and measurement. The results show that this antenna has been reduced by up to 27% in size from the normal log periodic planar dipole antenna. The performance of the antenna has been compared in terms of return losses, bandwidths, and radiation patterns. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26111