bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of organic solvent to prevent protein adsorption in CE‐MS experiments
Authors: Staub Aline , Comte Sylvain , Rudaz Serge , Veuthey Jean‐Luc , Schappler Julie 
Published: September 2010

AbstractProtein adsorption onto capillary wall often hampers CE separations, particularly in the CZE mode. Electrostatic interactions are not the only factors affecting adsorption, as hydrophobic interactions and/or protein conformational changes are also involved in the adsorption phenomenon. Numerous methods can be used to reduce or avoid adsorption, such as (i) addition of low molecular weight molecules in the BGE, (ii) use of surfactants, or (iii) capillary coatings. However, most of these methods are not MS‐compatible. In this study, we evaluated the addition of organic solvent as an alternative MS‐compatible method to decrease protein adsorption. The effect of the solvent addition was emphasized using classical methods for estimating reversible and irreversible adsorption. In many cases, organic solvents were effective at decreasing adsorption. However, the influence of the organic solvent on protein adsorption should be evaluated case‐by‐case in CE method development.
An automated capillary electrophoresis system for high‐speed separation of DNA fragments based on a short capillary
Authors: Cheng Yong‐Qiang , Yao Bo , Zhang Hui‐Dan , Fang Jin , Fang Qun 
Published: September 2010

AbstractA high‐speed DNA fragment separation system was developed based on a short capillary and a slotted‐vial array automated sample introduction system. The injection process of DNA sample in a short capillary was investigated systematically with three injection techniques including constant‐field‐strength, low‐field‐strength and translational spontaneous injections. Under the optimized conditions, picoliter‐scale sample plugs (corresponding to ca. 20‐μm plug length) were obtained, which ensure the high‐speed and high‐efficiency separation for DNA fragments with a short effective separation length. Other separation conditions including the sieving matrix concentration, separation field strength and effective separation length were also optimized. The present system was applied in the separation of ΦX174‐Hae III digest DNA marker. With an effective separation length of 2.5 cm, the separation could be achieved in <100 s with plate heights ranging from 0.21 to 0.74 μm (corresponding to plate numbers from 4.86×106 to 1.36×106/m). The repeatabilities for the migration time of the eleven fragments were between 0.4 and 1.1% RSD (n=8). By using the automated continuous injection method, the separation for four different DNA samples could be achieved within 250 s. The present system was further applied in the fast sizing of real DNA samples of PCR products.
Fairness‐aware user selection and resource allocation in MISO‐OFDMA
Authors: Papoutsis Vasileios D. , Fraimis Ioannis G. , Kotsopoulos Stavros A. 
Published: September 2010

AbstractThe problem of user selection and resource allocation for the downlink of wireless systems operating over a frequency‐selective channel is investigated. It is assumed that the Base Station (BS) uses many antennas, whereas a single antenna is available to each user (Multiple Input Single Output—MISO case). To relieve heavy computational burden, a suboptimal, but efficient algorithm is devised that is based on Zero Forcing (ZF) beamforming and is less complex than other approaches. The algorithm maximises the sum of the users' data rates subject to constraints on total available power and proportional fairness among users' data rates. Simulation results are provided to indicate that the algorithm can satisfy the fairness criterion. Thus, the algorithm can be applied to latest‐generation wireless systems that provide Quality‐of‐Service (QoS) guarantees. Copyright © 2010 John Wiley & Sons, Ltd.
Gender does not moderate hippocampal volume deficits in adults with posttraumatic stress disorder: A meta‐analysis
Authors: Woon Fu , Hedges Dawson W. 
Published: September 2010

AbstractEpidemiological studies show a higher point prevalence of posttraumatic stress disorder (PTSD) in women than in men, and early evidence has suggested that gender may moderate hippocampal volume deficits in PTSD. Our objective was to use random‐effects meta‐regression to assess gender effects on hippocampal volume deficits in PTSD. Using the terms posttraumatic stress disorder, gender, MRI, hippocampus, trauma, and abuse, we searched electronic databases for peer‐reviewed articles up to April 2009 containing data for hippocampal volume and gender composition in PTSD adults compared with controls. We identified 23 studies that met inclusion criteria and calculated effect sizes for differences in hippocampal mean volumes for each study and used the percentage of men with PTSD as a continuous moderating variable in meta‐regression. Additionally, we did a subgroup analysis of hippocampal volume deficits between women and men with gender as a categorical moderating variable. Hippocampal volumes were significantly smaller in the PTSD group compared to the control group, but gender did not significantly moderate any effect sizes in the meta‐regression or subgroup analyses. The lack of gender moderation on hippocampal volume deficits suggests that hippocampal volume deficits in PTSD are independent of gender. The higher prevalence of PTSD in females than in males does not correspond to increased hippocampal volume deficits in women with PTSD compared to men with PTSD, and neither gender appears protective against hippocampal volume deficits in adults with PTSD. © 2011 Wiley‐Liss, Inc.
The effects of selective hippocampal damage on tests of oddity in rhesus macaques
Authors: Alvarado Maria C. , Kazama Andy , Zeamer Alyson , Bachevalier Jocelyne 
Published: September 2010

AbstractThe oddity task (e.g., A−, A−, B+) is classified as a conjunctive or relational task in which accurate performance depends upon learning to attend to stimulus relationships, not stimulus identity, and has no retention component as stimuli are presented simultaneously. It has been suggested that the hippocampus may play a particular role in learning this type of task in humans and animals. To test this, we trained adult rhesus macaques with selective neurotoxic damage to the hippocampal formation on their ability to learn and apply an oddity rule. The results suggest that the monkeys were able to adapt simple strategies to solve variations of the oddity task, however as the opportunity for such strategies was reduced, monkeys with hippocampal damage were increasingly impaired. © 2010 Wiley‐Liss, Inc.
Dissociations within human hippocampal subregions during encoding and retrieval of spatial information
Authors: Suthana Nanthia , Ekstrom Arne , Moshirvaziri Saba , Knowlton Barbara , Bookheimer Susan 
Published: September 2010

AbstractAlthough the hippocampus is critical for the formation and retrieval of spatial memories, it is unclear how subregions are differentially involved in these processes. Previous high‐resolution functional magnetic resonance imaging (fMRI) studies have shown that CA2, CA3, and dentate gyrus (CA23DG) regions support the encoding of novel associations, whereas the subicular cortices support the retrieval of these learned associations. Whether these subregions are used in humans during encoding and retrieval of spatial information has yet to be explored. Using high‐resolution fMRI (1.6 mm × 1.6‐mm in‐plane), we found that activity within the right CA23DG increased during encoding compared to retrieval. Conversely, right subicular activity increased during retrieval compared to encoding of spatial associations. These results are consistent with the previous studies illustrating dissociations within human hippocampal subregions and further suggest that these regions are similarly involved during the encoding and retrieval of spatial information. © 2010 Wiley‐Liss, Inc.
Components of recognition memory: Dissociable cognitive processes or just differences in representational complexity?
Authors: Cowell Rosemary A. , Bussey Timothy J. , Saksida Lisa M. 
Published: September 2010

AbstractMany current theoretical views within the literature on recognition memory—a representative sample of which is provided by the present special issue—advocate the dissociation of recognition memory into two cognitive processes: familiarity‐based recognition, and recollection/recall. Furthermore, these processes are proposed to be mediated by distinct and dissociable anatomical regions, usually the perirhinal cortex and hippocampus, respectively. In this article, we describe a representational‐hierarchical view that provides an account of cognition, including mnemonic and perceptual processing, within a brain pathway we term the ventral visual‐perirhinal‐hippocampal stream. According to this view cognition, perception, memory, and indeed amnesia may be understood by considering the content and organization of stimulus representations in the brain. Taking this view leads us to question the idea of cognitive modules for introspectively derived notions such as familiarity and recollection. We begin by reviewing the representational‐hierarchical framework, explain how it has been used to account for object recognition memory in perirhinal cortex, and review the rationale for extending this framework to the hippocampus. We then discuss whether the principles of the representational‐hierarchical framework can be used to understand recollection and familiarity in terms of stimulus complexity, and use these principles to reconsider some of the evidence for neuroanatomical, dual‐process models of recognition memory. © 2010 Wiley‐Liss, Inc.
Changes in the two‐dimensional electrophoresis pattern of the Parkinson's disease related protein DJ‐1 in human SH‐SY5Y neuroblastoma cells after dopamine treatment
Authors: Alberio Tiziana , Colapinto Monica , Natale Massimo , Ravizza Raffaella , Gariboldi Marzia B. , Bucci Enrico M. , Lopiano Leonardo , Fasano Mauro 
Published: September 2010

AbstractChanges in the Two‐Dimensional Electrophoresis Pattern of the Parkinson's Disease Related Protein DJ‐1 in Human SH‐SY5Y Neuroblastoma Cells After Dopamine Treatment by Tiziana Alberio, Monica Colapinto, Massimo Natale, Raffaella Ravizza, Marzia B. Gariboldi, Enrico M. Bucci, Leonardo Lopiano, and Mauro Fasano, pp. 688–692.
Steric effects on alkyl cation affinities of maingroup‐element hydrides
Authors: Ruiz Juan M. , Mulder R. Joshua , Guerra Célia Fonseca , Bickelhaupt F. Matthias 
Published: September 2010

AbstractWe have carried out an extensive exploration of gas‐phase alkyl cation affinities (ACA) of archetypal anionic and neutral bases across the periodic system using zeroth order regular approximation‐relativistic density functional theory at BP86/QZ4P//BP86/TZ2P. ACA values were computed for the methyl, ethyl, i‐propyl and t‐butyl cations and compared with the corresponding proton affinities (PA). One purpose of this work is to provide an intrinsically consistent set of values of the 298 K ACA of all anionic (XH) and neutral bases (XHn) constituted by maingroup‐element hydrides of groups 14–17 and the noble gases (group 18) along the periods 1–6. Another purpose is to determine and rationalize the trend in affinity for a cation as the latter varies from proton to t‐butyl cation. This undertaking is supported by quantitative bond energy decomposition analyses. Correlations are established between PA and ACA values. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011
Exponential bounds on the number of designs with affine parameters
Authors: Clark David , Jungnickel Dieter , Tonchev Vladimir D. 
Published: September 2010

AbstractIt is well‐known that the number of designs with the parameters of a classical design having as blocks the hyperplanes in PG(n, q) or AG(n, q), n≥3, grows exponentially. This result was extended recently [D. Jungnickel, V. D. Tonchev, Des Codes Cryptogr, published online: 23 May, 2009] to designs having the same parameters as a projective geometry design whose blocks are the d‐subspaces of PG(n, q), for any 2≤d≤n−1. In this paper, exponential lower bounds are proved on the number of non‐isomorphic designs having the same parameters as an affine geometry design whose blocks are the d‐subspaces of AG(n, q), for any 2≤d≤n−1, as well as resolvable designs with these parameters. An exponential lower bound is also proved for the number of non‐isomorphic resolvable 3‐designs with the same parameters as an affine geometry design whose blocks are the d‐subspaces of AG(n, 2), for any 2≤d≤n−1. © 2010 Wiley Periodicals, Inc. J Combin Designs 18: 475–487, 2010
Automatic method for tracing regions of interest in rat brain magnetic resonance imaging studies
Authors: Nie Binbin , Hui Jiaojie , Wang Lijing , Chai Pei , Gao Juan , Liu Shuangquan , Zhang Zhijun , Shan Baoci , Zhao Shujun 
Published: September 2010

AbstractPurposeTo automatically extract regions of interest (ROIs) and simultaneously preserve the anatomical characteristics of each individual, we developed a new atlas‐based method utilizing a pair of coregistered brain template and digital atlas.Materials and MethodsUnlike the previous atlas‐based method, this method treats each individual as the target image, and the template and atlas are each transformed to register with the individual. To evaluate the accuracy of this method we implemented it in extracting the hippocampus from two groups of T2‐weighted structural images with different spatial resolutions and a group of T2*‐weighted functional images. Furthermore, the results were compared against a manually segmented hippocampus and an atlas‐derived hippocampus.ResultsJaccard similarity (JS) reached 84.7%–90.5%, and relative error in volume (RV) was 4.8%–12.7%. The consistency observed between the results of the proposed method and manual drawing was therefore considerable.ConclusionWe developed a new atlas‐based method for ROI extraction that can automatically extract ROI and simultaneously preserve each individual's unique anatomical characteristics. J. Magn. Reson. Imaging 2010;32:830–835. © 2010 Wiley‐Liss, Inc.
Percent infarct mapping for delayed contrast enhancement magnetic resonance imaging to quantify myocardial viability by Gd(DTPA)
Authors: Simor Tamás , Surányi Pál , Ruzsics Balázs , Tóth Attila , Tóth Levente , Kiss Pál , Brott Brigitta C. , Varga‐Szemes Ákos , Elgavish Ada , Elgavish Gabriel A. 
Published: September 2010

AbstractPurposeTo demonstrate the advantages of signal intensity percent‐infarct‐mapping (SI‐PIM) using the standard delayed enhancement (DE) acquisition in assessing viability following myocardial infarction (MI). SI‐PIM quantifies MI density with a voxel‐by‐voxel resolution in clinically used DE images.Materials and MethodsIn canines (n= 6), 96 hours after reperfused MI and administration of 0.2 mmol/kg Gd(DTPA), ex vivo DE images were acquired and SI‐PIMs calculated. SI‐PIM data were compared with data from DE images analyzed with several thresholding levels using SIremote+2SD, SIremote+6SD, SI full width half maximum (SIFWHM), and with triphenyl‐tetrazolium‐chloride (TTC) staining. SI‐PIM was also compared to R1 percent infarct mapping (R1‐PIM).ResultsLeft ventricular infarct volumes (IV) in DE images, IVSIremote+2SD and IVSIremote+6SD, overestimated (P < 0.05) TTC by medians of 13.21 mL [10.2; 15.2] and 6.2 mL [3.79; 8.23], respectively. SIFWHM, SI‐PIM, and R1‐PIM, however, only nonsignificantly underestimated TTC, by medians of −0.10 mL [−0.12, −0.06], −0.86 mL [−1.04; 1.54], and −1.30 mL [−4.99; −0.29], respectively. The infarct‐involved voxel volume (IIVV) of SI‐PIM, 32.4 mL [21.2, 46.3] is higher (P < 0.01) than IIVVs of SIFWHM 8.3 mL [3.79, 19.0]. SI‐PIMFWHM, however, underestimates TTC (−5.74 mL [−11.89; −2.52] (P < 0.01)). Thus, SI‐PIM outperforms SIFWHM because larger IIVVs are obtained, and thus PIs both in the rim and the core of the infarcted tissue are characterized, in contradistinction from DE‐SIFWHM, which shows mainly the infarct core.ConclusionWe have shown here, ex vivo, that SI‐PIM has the same advantages as R1‐PIM, but it is based on the scanning sequences of DE imaging, and thus it is obtainable within the same short scanning time as DE. This makes it a practical method for clinical studies. J. Magn. Reson. Imaging 2010;32:859–868. © 2010 Wiley‐Liss, Inc.
Magnetic resonance imaging near metal implants
Authors: Koch K.M. , Hargreaves B.A. , Pauly K. Butts , Chen W. , Gold G.E. , King K.F. 
Published: September 2010

AbstractThe desire to apply magnetic resonance imaging (MRI) techniques in the vicinity of embedded metallic hardware is increasing. The soft‐tissue contrast available with MR techniques is advantageous in diagnosing complications near an increasing variety of MR‐safe metallic hardware. Near such hardware, the spatial encoding mechanisms utilized in conventional MRI methods are often severely compromised. Mitigating these encoding difficulties has been the focus of numerous research investigations over the past two decades. Such approaches include view‐angle tilting, short echo‐time projection reconstruction acquisitions, single‐point imaging, prepolarized MRI, and postprocessing image correction. Various technical advances have also enabled the recent development of two alternative approaches that have shown promising clinical potential. Here, the physical principals and proposed solutions to the problem of MRI near embedded metal are discussed. J. Magn. Reson. Imaging 2010;32:773–787. © 2010 Wiley‐Liss, Inc.
Fat‐water separation in dynamic objects using an UNFOLD‐like temporal processing
Authors: Ababneh Riad , Yuan Jing , Madore Bruno 
Published: September 2010

AbstractPurposeTo separate fat and water signals in dynamic imaging. Because important features may be embedded in fat, and because fat may take part in disease processes, separating fat and water signals may be of great importance in a number of clinical applications. This work aims to achieve such separation at nearly no loss in temporal resolution compared to usual, nonseparated acquisitions. In contrast, the well‐known 3‐point Dixon method may cause as much as a 3‐fold reduction in temporal resolution.Materials and MethodsThe proposed approach involves modulating the echo time TE from frame to frame, to force fat signals to behave in a conspicuous manner through time, so they can be readily identified and separated from water signals. The strategy is inspired from the “unaliasing by Fourier encoding the overlaps in the temporal direction” (UNFOLD) method, although UNFOLD involves changes in the sampling function rather than TE, and aims at suppressing aliased material rather than fat.ResultsThe method was implemented at 1.5 T and 3 T, on cardiac cine and multiframe steady‐state free precession sequences. In addition to phantom results, in vivo results from volunteers are presented.ConclusionGood separation of fat and water signals was achieved in all cases. J. Magn. Reson. Imaging 2010;32:962–970. © 2010 Wiley‐Liss, Inc.
Functional MRI of liver using BOLD MRI: Effect of glucose
Authors: Haque Muhammad , Koktzoglou Ioannis , Li Wei , Carbray JoAnn , Prasad Pottumarthi 
Published: September 2010

AbstractPurposeTo demonstrate feasibility of functional MRI of liver using glucose as a stimulus to monitor metabolic changes using blood oxygenation level dependent (BOLD) contrast. We hypothesized that during hyperglycemia, liver stores the glucose and consequently there is a reduction in oxygen consumption, which can be detected using BOLD MRI.Materials and MethodsIn four mini pigs, measurements were made before and after 54 g of glucose administered intravenously. In six healthy young human subjects, measurements were made before and after oral ingestion of 75 g of glucose. T2* weighted images of the liver were obtained on a Siemens 3 Tesla Verio MRI scanner using multiple gradient recalled echo (mGRE) sequence.ResultsA statistically significant decrease (P < 0.05) in R2* (1/T2*) was observed postglucose both in swine (110.41 ± 14.1 s−1 to 72.22 ± 5.7 s−1) and human (55.84 ±3.8 s−1 to 50.6 ±0.5 s−1), suggesting improved liver oxygenation during hyperglycemia.ConclusionOur preliminary data presented here demonstrate the feasibility of obtaining functional liver images that illustrate the changes in oxygen consumption. Further studies are necessary to fully validate the technique. J. Magn. Reson. Imaging 2010;32:988–991. © 2010 Wiley‐Liss, Inc.
In vivo quantification of murine aortic cyclic strain, motion, and curvature: Implications for abdominal aortic aneurysm growth
Authors: Goergen Craig J. , Barr Kyla N. , Huynh Diem T. , Eastham‐Anderson Jeffrey R. , Choi Gilwoo , Hedehus Maj , Dalman Ronald L. , Connolly Andrew J. , Taylor Charles A. , Tsao Philip S. , Greve Joan M. 
Published: September 2010

AbstractPurposeTo develop methods to quantify cyclic strain, motion, and curvature of the murine abdominal aorta in vivo.Materials and MethodsC57BL/6J and apoE−/− mice underwent three‐dimensional (3D) time‐of‐flight MR angiography to position cardiac‐gated 2D slices at four locations along the abdominal aorta where circumferential cyclic strain and lumen centroid motion were calculated. From the 3D data, a centerline through the aorta was created to quantify geometric curvature at 0.1‐mm intervals. Medial elastin content was quantified with histology postmortem. The location and shape of abdominal aortic aneurysms (AAAs), created from angiotensin II infusion, were evaluated qualitatively.ResultsStrain waveforms were similar at all locations and between groups. Centroid motion was significantly larger and more leftward above the renal vessels than below (P < 0.05). Maximum geometric curvature occurred slightly proximal to the right renal artery. Elastin content was similar around the circumference of the vessel. AAAs developed in the same location as the maximum curvature and grew in the same direction as vessel curvature and motion.ConclusionThe methods presented provide temporally and spatially resolved data quantifying murine aortic motion and curvature in vivo. This noninvasive methodology will allow serial quantification of how these parameters influence the location and direction of AAA growth. J. Magn. Reson. Imaging 2010;32:847–858. © 2010 Wiley‐Liss, Inc.
Improving proton MR spectroscopy of brain tissue for noninvasive diagnostics
Authors: Alusta Pierre , Im Inessa , Pearce Bruce A. , Beger Richard D. , Kretzer Ryan M. , Buzatu Dan A. , Wilkes Jon G. 
Published: September 2010

AbstractPurposeTo examine preprocessing methods affecting the potential use of Magnetic Resonance Spectroscopy (MRS) as a noninvasive modality for detection and characterization of brain lesions and for directing therapy progress.Materials and MethodsTwo reference point re‐calibration with linear interpolation (to compensate for magnetic field nonhomogeneity), weighting of spectra (to emphasize consistent peaks and depress chemical noise), and modeling based on chemical shift locations of 97 biomarkers were investigated. Results for 139 categorized scans were assessed by comparing Leave‐One‐Out (LOO) cross‐validation and external validation.ResultsFor distinction of nine brain tissue categories, use of re‐calibration, variance weighting, and biomarker modeling improved LOO classification of MRS spectra from 31% to 95%. External validation of the two best nine‐category models on 47 unknown samples gave 96% or 100% accuracy, respectively, compared with pathological diagnosis.ConclusionPreprocessing of MRS spectra can significantly improve their diagnostic utility for automated consultation of pattern recognition models. Use of several techniques in combination greatly increases available proton MRS information content. Accurate assignment of unknowns among nine tissue classes represents a significant improvement, for a much more demanding task, than has been previously reported. J. Magn. Reson. Imaging 2010;32:818–829. © 2010 Wiley‐Liss, Inc.