bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of normal spinal veins by using susceptibility‐weighted imaging
Authors: Ishizaka Kinya , Kudo Kohsuke , Fujima Noriyuki , Zaitsu Yuri , Yazu Rie , Tha Khin Khin , Terae Satoshi , Haacke E. Mark , Sasaki Makoto , Shirato Hiroki 
Published: December 2009

AbstractPurpose:To evaluate the visualization of the spinal veins using susceptibility‐weighted imaging (SWI).Materials and Methods:A 1.5‐T magnet equipped with a spine matrix coil was used. Axial SWI scans of 20 healthy volunteers were obtained with a three‐dimensional fast low‐angle shot (3D‐FLASH) sequence. Maximum intensity projection (MIP) of the phase images were reconstructed and five MIP images (at the levels of T11, T11/12, T12, T12/L1, and L1) were selected for the evaluation. The anterior median vein (AMV), posterior median vein (PMV), anterior radiculomedullary vein (ARV), posterior radiculomedullary vein (PRV), and sulcal vein (SV) were evaluated using a 4‐grade scale (0, none; 1, weak; 2, moderate; and 3, prominent).Results:The AMV was detected in all the subjects (100%). The detection rates of the other veins were lower: PMV, 65%; right ARV, 45%; left ARV, 15%; right PRV, 10%; left PRV, 30%; and SV, 0%. The average scores for AMV, PMV, right ARV, left ARV, right PRV, left PRV, and SV were 0.98, 0.24, 0.20, 0.08, 0.08, 0.14, and 0, respectively.Conclusion:SWI of the spine is feasible. The extrinsic spinal veins can be visualized by SWI without using contrast materials. J. Magn. Reson. Imaging 2010;31:32–38. © 2009 Wiley‐Liss, Inc.
Susceptibility weighted imaging with multiple echoes
Authors: Denk Christian , Rauscher Alexander 
Published: December 2009

AbstractPurpose:To extend susceptibility weighted imaging (SWI) to multiple echoes with an adapted homodyne filtering of phase images for the computation of venograms with improved signal to noise ratio (SNR) and contrast to noise ratio (CNR) and to produce high resolution maps of R2* relaxation.Materials and Methods:Three‐dimensional multi echo gradient echo data were acquired with five equidistant echoes ranging from 13 to 41 ms. The phase images of each echo were filtered with filter parameters adjusted to the echo time, converted into a phase mask, and combined with the corresponding magnitude images to obtain susceptibility weighted images. The individual images were then averaged. Conventional single echo data were acquired for comparison. Maps of R2* relaxation rates were computed from the magnitude data. Field maps derived from the phase data were used to correct R2* for the influences from background inhomogeneities of the static magnetic field.Results:Compared with the single echo images, the combined images had an increase in SNR by 46% and an improvement in CNR by 34 to 80%, improved visibility of small venous vessels and reduced blurring along the readout direction. The R2* values of different tissue types are in good agreement with values from the literature.Conclusion:Acquisition of SWI with multiple echoes leads to an increase in SNR and CNR and it allows the computation of high resolution maps of R2* relaxation. J. Magn. Reson. Imaging 2010;31:185–191. © 2009 Wiley‐Liss, Inc.
Hybrid of opposite‐contrast MRA of the brain by combining time‐of‐flight and black‐blood sequences: Initial experience in major trunk stenoocclusive diseases
Authors: Tsuchiya Kazuhiro , Kobayashi Kuninori , Nitatori Toshiaki , Kimura Tokunori , Ikedo Masato , Takemoto Shuhei 
Published: December 2009

AbstractPurpose:To assess the feasibility of a new MR angiography (MRA) technique named hybrid of opposite‐contrast MRA (HOP MRA) that combined the time‐of‐flight (TOF) MRA with a flow‐sensitive black‐blood (FSBB) sequence in the diagnosis of major trunk stenoocclusive diseases.Materials and Methods:On a 1.5 Tesla imager using a dual‐echo three‐dimensional (3D)‐gradient‐echo sequence, we obtained the first echo for TOF MRA followed by the second echo for FSBB. We then subtracted the FSBB data set from that of TOF MRA followed by maximum intensity projection. In four normal volunteers and 19 patients with chronic stenoocclusive disease of the major trunk, we performed HOP MRA along with 3D‐TOF MRA and compared the findings.Results:In the volunteer group, the HOP MRA technique improved the demonstration of distal arterial branches. In 12 of the 19 patients, the HOP MRA better visualized branches distal to the lesion as well as distal branches of normal trunks than 3D‐TOF MRA, while both techniques provided equivalent depiction of branches distal to the lesion but better depiction of normal distal branches in three patients.Conclusion:The HOP‐MRA technique is promising in major trunk stenoocclusive diseases as it better demonstrates distal branches probably representing collaterals than 3D‐TOF MRA. J. Magn. Reson. Imaging 2010;31:56–60. © 2009 Wiley‐Liss, Inc.
Adaptive non‐local means denoising of MR images with spatially varying noise levels
Authors: Manjón José V. , Coupé Pierrick , Martí‐Bonmatí Luis , Collins D. Louis , Robles Montserrat 
Published: December 2009

AbstractPurpose:To adapt the so‐called nonlocal means filter to deal with magnetic resonance (MR) images with spatially varying noise levels (for both Gaussian and Rician distributed noise).Materials and Methods:Most filtering techniques assume an equal noise distribution across the image. When this assumption is not met, the resulting filtering becomes suboptimal. This is the case of MR images with spatially varying noise levels, such as those obtained by parallel imaging (sensitivity‐encoded), intensity inhomogeneity‐corrected images, or surface coil‐based acquisitions. We propose a new method where information regarding the local image noise level is used to adjust the amount of denoising strength of the filter. Such information is automatically obtained from the images using a new local noise estimation method.Results:The proposed method was validated and compared with the standard nonlocal means filter on simulated and real MRI data showing an improved performance in all cases.Conclusion:The new noise‐adaptive method was demonstrated to outperform the standard filter when spatially varying noise is present in the images. J. Magn. Reson. Imaging 2010;31:192–203. © 2009 Wiley‐Liss, Inc.
Computer‐aided detection of metastatic brain tumors using automated three‐dimensional template matching
Authors: Ambrosini Robert D. , Wang Peng , O'Dell Walter G. 
Published: December 2009

AbstractPurpose:To demonstrate the efficacy of an automated three‐dimensional (3D) template matching‐based algorithm in detecting brain metastases on conventional MR scans and the potential of our algorithm to be developed into a computer‐aided detection tool that will allow radiologists to maintain a high level of detection sensitivity while reducing image reading time.Materials and Methods:Spherical tumor appearance models were created to match the expected geometry of brain metastases while accounting for partial volume effects and offsets due to the cut of MRI sampling planes. A 3D normalized cross‐correlation coefficient was calculated between the brain volume and spherical templates of varying radii using a fast frequency domain algorithm to identify likely positions of brain metastases.Results:Algorithm parameters were optimized on training datasets, and then data were collected on 22 patient datasets containing 79 total brain metastases producing a sensitivity of 89.9% with a false positive rate of 0.22 per image slice when restricted to the brain mass.Conclusion:Study results demonstrate that the 3D template matching‐based method can be an effective, fast, and accurate approach that could serve as a useful tool for assisting radiologists in providing earlier and more definitive diagnoses of metastases within the brain. J. Magn. Reson. Imaging 2010;31:85–93. © 2009 Wiley‐Liss, Inc.
Measuring the heart in pulmonary arterial hypertension (PAH): Implications for trial study size
Authors: Bradlow William M. , Hughes Marina L. , Keenan Niall G. , Bucciarelli‐Ducci Chiara , Assomull Ravi , Gibbs J. Simon R. , Mohiaddin Raad H. 
Published: December 2009

AbstractPurpose:To calculate the sample size for a theoretical pulmonary arterial hypertension (PAH) randomized controlled trial (RCT) by using cardiovascular magnetic resonance (CMR) imaging to determine the repeatability of measures between two scans.Materials and Methods:Two same‐day examinations from 10 PAH patients were analyzed manually and semiautomatically. Study size was calculated from the standard deviation (SD) of repeatability. Different approaches to right‐ventricle (RV) mass were investigated, agreement between methods tested and interobserver reproducibility measured by Bland‐Altman analysis to explore how the PAH heart might be best measured.Results:Repeatability was good for almost all manually‐measured indices but poor for semiautomated measurement of RV mass and left‐ventricle (LV) end‐diastolic volume (EDV). Thus, for an RCT (power, 80%; significance level, 5%) analyzing “outcome” indices (RVEDV, LVEDV, RV ejection fraction, and RV mass; anticipated change: 10 mL, 10 mL, 3%, and 10 g, respectively) manually, 34 patients are required compared to 78 if analysis is semiautomated. RV mass was repeatable if the interventricular septum was divided between ventricles or if wholly apportioned to the LV. Limits of agreement between manual and semiautomated analyses were unsatisfactory for RV measures and interobserver reproducibility was worse for semiautomated than manual analysis.Conclusion:Manual is more robust than semiautomated analysis and at present should be favored in RCTs in PAH as it leads to lower sample size requirements. J. Magn. Reson. Imaging 2010;31:117–124. © 2009 Wiley‐Liss, Inc.
A population‐specific symmetric phase model to automatically analyze susceptibility‐weighted imaging (SWI) phase shifts and phase symmetry in the human brain
Authors: Grabner Günther , Haubenberger Dietrich , Rath Jakob , Beisteiner Roland , Auff Eduard , Trattnig Siegfried , Barth Markus 
Published: December 2009

AbstractPurpose:To create a population‐specific symmetric phase model and to evaluate the susceptibility‐weighted imaging (SWI) phase in terms of phase shift using different segmentation methods (manual and automatic) and phase shift symmetry, which is expected as a marker for lateralized Parkinson's disease (PD) symptoms.Materials and Methods:SWI and T1‐weighted data from 25 PD patients and five healthy controls were acquired on a 3T MRI system. A population‐specific, symmetric phase model was developed. Regions of interest (ROIs) were defined manually on the phase model, manually on each individual data set, and automatically using model‐based segmentation (MBS). Manually‐ and MBS‐defined ROIs were compared using kappa values, and left‐right phase symmetry was evaluated using correlation analysis.Results:Independent of the analysis method, a phase increase from the anterior to the posterior putamen, and the average phase value relationship substantia nigra > globus pallidus > red nucleus was found. Phase symmetry analysis shows a difference between lateralized and symmetric PD.Conclusion:The symmetric phase model helps to analyze phase data with similar accuracy, but a greatly reduced tracing effort compared to individual tracing and also allows evaluating left‐right phase symmetries. J. Magn. Reson. Imaging 2010;31:215–220. © 2009 Wiley‐Liss, Inc.
PROMO: Real‐time prospective motion correction in MRI using image‐based tracking
Authors: White Nathan , Roddey Cooper , Shankaranarayanan Ajit , Han Eric , Rettmann Dan , Santos Juan , Kuperman Josh , Dale Anders 
Published: December 2009

AbstractArtifacts caused by patient motion during scanning remain a serious problem in most MRI applications. The prospective motion correction technique attempts to address this problem at its source by keeping the measurement coordinate system fixed with respect to the patient throughout the entire scan process. In this study, a new image‐based approach for prospective motion correction is described, which utilizes three orthogonal two‐dimensional spiral navigator acquisitions, along with a flexible image‐based tracking method based on the extended Kalman filter algorithm for online motion measurement. The spiral navigator/extended Kalman filter framework offers the advantages of image‐domain tracking within patient‐specific regions‐of‐interest and reduced sensitivity to off‐resonance‐induced corruption of rigid‐body motion estimates. The performance of the method was tested using offline computer simulations and online in vivo head motion experiments. In vivo validation results covering a broad range of staged head motions indicate a steady‐state error of less than 10% of the motion magnitude, even for large compound motions that included rotations over 15 deg. A preliminary in vivo application in three‐dimensional inversion recovery spoiled gradient echo (IR‐SPGR) and three‐dimensional fast spin echo (FSE) sequences demonstrates the effectiveness of the spiral navigator/extended Kalman filter framework for correcting three‐dimensional rigid‐body head motion artifacts prospectively in high‐resolution three‐dimensional MRI scans. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
Optimal blood glucose regulation of diabetic patients using single network adaptive critics
Authors: Ali Sk. Faruque , Padhi Radhakant 
Published: December 2009

AbstractDiabetes is a long‐term disease during which the body's production and use of insulin are impaired, causing glucose concentration level to increase in the bloodstream. Regulating blood glucose levels as close to normal as possible leads to a substantial decrease in long‐term complications of diabetes. In this paper, an intelligent online feedback‐treatment strategy is presented for the control of blood glucose levels in diabetic patients using single network adaptive critic (SNAC) neural networks (which is based on nonlinear optimal control theory). A recently developed mathematical model of the nonlinear dynamics of glucose and insulin interaction in the blood system has been revised and considered for synthesizing the neural network for feedback control. The idea is to replicate the function of pancreatic insulin, i.e. to have a fairly continuous measurement of blood glucose and a situation‐dependent insulin injection to the body using an external device. Detailed studies are carried out to analyze the effectiveness of this adaptive critic‐based feedback medication strategy. A comparison study with linear quadratic regulator (LQR) theory shows that the proposed nonlinear approach offers some important advantages such as quicker response, avoidance of hypoglycemia problems, etc. Robustness of the proposed approach is also demonstrated from a large number of simulations considering random initial conditions and parametric uncertainties. Copyright © 2009 John Wiley & Sons, Ltd.
High‐performance nanocomposites based on arcylonitrile‐butadiene rubber with fillers of different particle size: Mechanical and morphological studies
Authors: Thomas P.C. , Tomlal Jose E , Selvin Thomas P , Thomas Sabu , Joseph Kuruvilla 
Published: December 2009

AbstractAcrylonitrile‐butadiene rubber (NBR) nanocomposites with layered silicate (LS), calcium phosphate (CP), and titanium dioxide (TO) of different particle size were prepared in an open two‐roll mixing mill at different filler loading in presence of sulphur as vulcanizing agent. The layered silicate (LS) filled system showed outstanding enhancement in mechanical properties in comparison with nanocalcium phosphate (CP) and titanium dioxide (TO). The variations in properties can be attributed to the extent of intercalation/exfoliation, which was highly influenced by the filler size. The layered silicate filled system at 20 phr showed nearly 349% increase in tensile strength compared to pure NBR whereas an increase of 110% and 84% were shown by CP and TO filled systems respectively. The modulus enhancements were in the order of 200%, 63% and 22%, respectively compared to the unfilled system. The increase in tear resistance was in the order of 230%, 115%, and 41% respectively for the filled systems in comparison with unfilled NBR. The significant enhancements in mechanical properties were supported by the morphological analysis. POLYM. COMPOS., 31:1515–1524, 2010. © 2009 Society of Plastics Engineers
Experimental analysis for extrusion screw geometry to produce highly transparent polypropylene sheets
Authors: Funaki Akira , Takubo Toyokazu , Kanai Toshitaka 
Published: December 2009

AbstractThe observation was experimentally conducted by using many screws with various geometries to obtain a highly transparent polypropylene melt resin sheet. The pressure distribution in the extruder, melt temperature profile across melt flow, the extruder throughput and the specific energy consumption were monitored. In a preliminary evaluation, transparent melt web was obtained in a simple straight channel depth screw and a straight channel depth screw with a torpedo type barrier section. The transparency of melted resin sheet was obtained by the screw geometry so that the specific energy consumption was small and the melted temperature was low. Based on these results and taking a wide applicability for a large size extruder of the production machine into consideration, the screw of gently tapered compression with a torpedo type barrier section was selected as the basic design of the screw geometry to satisfy both the transparency and the extrusion stability. The screw geometry optimization was conducted using the analysis of melting performance by the cooling experiment and the pressure pattern. As a result, the screw geometry to satisfy a low external haze and an extrusion stability under higher throughput conditions was designed. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Assessing effectiveness and efficiency of academic interventions in school psychology journals: 1995–2005
Authors: Bramlett Ron , Cates Gary L. , Savina Elena , Lauinger Brittni 
Published: December 2009

AbstractThis article reviews research in the four major school psychology journals: Journal of School Psychology, Psychology in the Schools, School Psychology Quarterly, and School Psychology Review. The function of the review was to provide school psychologists with a summary of academic interventions published through years 1995–2005, synthesize the commonalities of empirically based interventions, and report on the extent to which each article provides the reader the opportunity to understand the effects of the intervention with regard to the amount of instructional time required to implement it. Results of the review suggest that reading is most heavily investigated followed by math and, to a much lesser degree, written expression. Moreover, studies use a variety of designs including single subject and group designs. Finally, it is clear that a limited number of studies evaluate the effectiveness of an intervention with regard to the amount of instructional time needed to implement the intervention. In light of these findings and in addition to the two major functions of the review, recommendations for practice and future research are presented. © 2009 Wiley Periodicals, Inc.
Morphing, Zoom und 3D. Lamellen‐ und Linsenrasterbilder
Authors: Ucke Christian , Schlichting Hans‐Joachim 
Published: December 2009

AbstractSchon seit Jahrhunderten ist die Technik der Riefel‐ oder Lamellenbilder bekannt, mit der zwei oder drei Bilder in ein Bild zusammengefasst werden. Mit der Linsenrastertechnik kann man heute bis zu dreißig unterschiedliche Bilder in eine ebene Druckvorlage unterbringen. Damit lassen sich Wechselbilder, 3D‐Bilder, ja sogar kleine Videosequenzen realisieren. Linsenraster bestehen aus einer Anordnung von parallelen Zylinderlinsen.
Elektrofahrzeuge. Mobilität und erneuerbare Energie
Authors: Vezzini Andrea 
Published: December 2009

AbstractReine Elektroautos sind im Betrieb Nullemissionsfahrzeuge, sofern sie mit CO2‐frei erzeugtem Strom fahren. Aber auch mit fossil erzeugtem Strom kommen sie auf eine gute CO2‐Bilanz. Der Grund: Elektromotoren haben über 90 % Wirkungsgrad (Diesel 35 %) und kommen sogar ohne Getriebe aus. Der Flaschenhals ist nach wie vor die teure und schwere Batterie mit niedriger Speicherkapazität. Die schnellen Fortschritte in der Lithiumionen‐Technologie lassen jedoch auf einen Durchbruch im kommenden Jahrzehnt hoffen. Große Autobatterien benötigen ein aufwendiges Batteriemanagement, um sicher zu sein und eine hohe Lebensdauer zu erreichen.
Correlation of 2J couplings with protein secondary structure
Authors: Schmidt Jürgen M. , Hua Yixun , Löhr Frank 
Published: December 2009

AbstractGeminal two‐bond couplings (2J) in proteins were analyzed in terms of correlation with protein secondary structure. NMR coupling constants measured and evaluated for a total six proteins comprise 3999 values of 2JCαN′, 2JC′HN, 2JHNCα, 2JC′Cα, 2JHαC′, 2JHαCα, 2JCβC′, 2JN′Hα, 2JN′Cβ, and 2JN′C′, encompassing an aggregate 969 amino‐acid residues. A seamless chain of pattern comparisons across the spectrum datasets recorded allowed the absolute signs of all 2J coupling constants studied to be retrieved. Grouped by their mediating nucleus, C′, N′ or Cα, 2J couplings related to C′ and N′ depend significantly on ϕ,ψ torsion‐angle combinations. β turn types I, I′, II and II′, especially, can be distinguished on the basis of relative‐value patterns of 2JCαN′, 2JHNCα, 2JC′HN, and 2JHαC′. These coupling types also depend on planar or tetrahedral bond angles, whereas such dependences seem insignificant for other types. 2JHαCβ appears to depend on amino‐acid type only, showing negligible correlation with torsion‐angle geometry. Owing to its unusual properties, 2JCαN′ can be considered a “one‐bond” rather than two‐bond interaction, the allylic analog of 1JN′Cα, as it were. Of all protein J coupling types, 2JCαN′ exhibits the strongest dependence on molecular conformation, and among the 2J types, 2JHNCα comes second in terms of significance, yet was hitherto barely attended to in protein structure work. Proteins 2010. © 2009 Wiley‐Liss, Inc.
Amino acid substitutions at protein–protein interfaces that modulate the oligomeric state
Authors: Nishi Hafumi , Ota Motonori 
Published: December 2009

AbstractDespite similarities in their sequence and structure, there are a number of homologous proteins that adopt various oligomeric states. Comparisons of these homologous protein pairs, in terms of residue substitutions at the protein–protein interfaces, have provided fundamental characteristics that describe how proteins interact with each other. We have prepared a dataset composed of pairs of related proteins with different homo‐oligomeric states. Using the protein complexes, the interface residues were identified, and using structural alignments, the shadow‐interface residues have been defined as the surface residues that align with the interface residues. Subsequently, we investigated residue substitutions between the interfaces and the shadow interfaces. Based on the degree of the contributions to the interactions, the aligned sites of the interfaces and shadow interfaces were divided into primary and secondary sites; the primary sites are the focus of this work. The primary sites were further classified into two groups (i.e. exposed and buried) based on the degree to which the residue is buried within the shadow interfaces. Using these classifications, two simple mechanisms that mediate the oligomeric states were identified. In the primary‐exposed sites, the residues on the shadow interfaces are replaced by more hydrophobic or aromatic residues, which are physicochemically favored at protein–protein interfaces. In the primary‐buried sites, the residues on the shadow interfaces are replaced by larger residues that protrude into other proteins. These simple rules are satisfied in 23 out of 25 Structural Classification of Proteins (SCOP) families with a different‐oligomeric‐state pair, and thus represent a basic strategy for modulating protein associations and dissociations. Proteins 2010. © 2009 Wiley‐Liss, Inc.