bluuebunny/crossref_metadata_2025_split huggingface dataset:
High‐resolution magnetization‐prepared 3D‐FLAIR imaging at 7.0 Tesla
Authors: Visser Fredy , Zwanenburg Jaco J. M. , Hoogduin Johannes M. , Luijten Peter R. 
Published: May 2010

AbstractThe aim of the present study is to develop a submillimeter volumetric (three‐dimensional) fluid‐attenuated inversion recovery sequence at 7T. Implementation of the fluid‐attenuated inversion recovery sequence is difficult as increased T1 weighting from prolonged T1 constants at 7T dominate the desired T2 contrast and yield suboptimal signal‐to‐noise ratio. Magnetization preparation was used to reduce T1 weighting and improve the T2 weighting. Also, practical challenges limit the implementation. Long refocusing trains with low flip angles were used to mitigate the specific absorption rate constraints. This resulted in a three‐dimensional magnetization preparation fluid‐attenuated inversion recovery sequence with 0.8 × 0.8 × 0.8 = 0.5 mm3 resolution in a clinically acceptable scan time. The contrast‐to‐noise ratio between gray matter and white matter (contrast‐to‐noise ratio = signal‐to‐noise ratio [gray matter] − signal‐to‐noise ratio [white matter]) increased from 12 ± 9 without magnetization preparation to 28 ± 8 with magnetization preparation (n = 12). The signal‐to‐noise ratio increased for white matter by 13 ± 6% and for gray matter by 48 ± 15%. In conclusion, three‐dimensional fluid‐attenuated inversion recovery with high resolution and full brain coverage is feasible at 7T. Magnetization preparation reduces the T1 weighting, thereby improving the T2 weighted contrast and signal‐to‐noise ratio. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Preferential patterns of myocardial iron overload by multislice multiecho T*2 CMR in thalassemia major patients
Authors: Meloni Antonella , Positano Vincenzo , Pepe Alessia , Rossi Giuseppe , Dell'Amico MariaChiara , Salvatori Cristina , Keilberg Petra , Filosa Aldo , Sallustio Giuseppina , Midiri Massimo , D'Ascola Domenico , Santarelli Maria Filomena , Lombardi Massimo 
Published: May 2010

AbstractT*2 multislice multiecho cardiac MR allows quantification of the segmental distribution of myocardial iron overload. This study aimed to determine if there were preferential patterns of myocardial iron overload in thalassemia major. Five hundred twenty‐three thalassemia major patients underwent cardiac MR. Three short‐axis views of the left ventricle were acquired and analyzed using a 16‐segment standardized model. The T*2 value on each segment was calculated, as well as the global value. Four main circumferential regions (anterior, septal, inferior, and lateral) were defined. Significant segmental variability was found in the 229 patients with significant myocardial iron overload (global T*2 <26 ms), subsequently divided into two groups: severe (global T*2 <10 ms) and mild to moderate (global T*2 between 10 and 26 ms) myocardial iron overload. A preferential pattern of iron store in anterior and inferior regions was detected in both groups. This pattern was preserved among the slices. The pattern could not be explained by additive susceptibility artifacts, negligible in heavily iron‐loaded patients. A significantly higher T*2 value in the basal slice was found in patients with severe iron overload. In conclusion, a segmental T*2 cardiac MR approach could identify early iron deposit, useful for tailoring chelation therapy and preventing myocardial dysfunction in the clinical setting. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Optimized parallel imaging for dynamic PC‐MRI with multidirectional velocity encoding
Authors: Peng Hsu‐Hsia , Bauer Simon , Huang Teng‐Yi , Chung Hsiao‐Wen , Hennig Jürgen , Jung Bernd , Markl Michael 
Published: May 2010

AbstractPhase contrast MRI with multidirectional velocity encoding requires multiple acquisitions of the same k‐space lines to encode the underlying velocities, which can considerably lengthen the total scan time. To reduce scan time, parallel imaging is often applied. In dynamic phase contrast MRI using standard generalized autocalibrating partially parallel acquisitions (GRAPPA), several central k‐spaces for autocalibration of the reconstruction (autocalibrating signal lines (ACS)) are typically acquired, separately for each velocity direction and each cardiac timeframe, for calculating the reconstruction weights. To further accelerate data acquisition, we developed two methods, which calculated weights with a substantially reduced number of ACSl lines. The effects on image quality and flow quantification were compared to fully sampled data, standard GRAPPA, and time‐interleaved sampling scheme in combination with generalized autocalibrating partially parallel acquisitions (TGRAPPA). The results show that the two proposed methods can clearly improve scan efficiency while maintaining image quality and accuracy of measured flow or myocardial tissue velocities. Compared to TGRAPPA, the proposed methods were more accurate in evaluating flow velocity. In conclusion, the proposed reconstruction strategies are promising for dynamic multidirectionally encoded acquisitions and can easily be implemented using the standard GRAPPA reconstruction algorithm. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Optimal transportation meshfree approximation schemes for fluid and plastic flows
Authors: Li B. , Habbal F. , Ortiz M. 
Published: May 2010

AbstractWe develop an optimal transportation meshfree (OTM) method for simulating general solid and fluid flows, including fluid–structure interaction. The method combines concepts from optimal transportation theory with material‐point sampling and max‐ent meshfree interpolation. The proposed OTM method generalizes the Benamou–Brenier differential formulation of optimal mass transportation problems to problems including arbitrary geometries and constitutive behavior. The OTM method enforces mass transport and essential boundary conditions exactly and is free from tension instabilities. The OTM method exactly conserves linear and angular momentum and its convergence characteristics are verified in standard benchmark problems. We illustrate the range and scope of the method by means of two examples of application: the bouncing of a gas‐filled balloon off a rigid wall; and the classical Taylor‐anvil benchmark test extended to the hypervelocity range. Copyright © 2010 John Wiley & Sons, Ltd.
Three‐dimensional finite element implementation of the nonuniform transformation field analysis
Authors: Fritzen Felix , Böhlke T. 
Published: May 2010

AbstractIn this paper aspects of the nonuniform transformation field analysis (NTFA) introduced by Michel and Suquet (Int. J. Solids Struct. 2003; 40:6937–6955) are investigated for materials with three‐dimensional microtopology. A novel implementation of the NTFA into the finite element method (FEM) is described in detail, whereas the NTFA was originally used in combination with the fast Fourier transformation (FFT). In particular, the discrete equivalents of the averaging operators required for the preprocessing steps and an algorithm for the implicit time integration and linearization of the constitutive equations of the homogenized material are provided. To the authors knowledge this is the first implementation of the method for three‐dimensional problems. Further, an alternative mode identification strategy is proposed with the aim of small computational cost in combination with good efficiency. The new identification strategy is applied to three‐dimensional metal matrix composites in order to investigate its effective non‐linear behaviour. The homogenized material model is implemented into ABAQUS/STANDARD. Numerical examples at integration point level and in terms of structural problems highlight the efficiency of the method for three‐dimensional problems. Copyright © 2010 John Wiley & Sons, Ltd.
Bounded renormalization with continuous penalization for level set interface‐capturing methods
Authors: Battaglia L. , Storti M. A. , D'Elía J. 
Published: May 2010

AbstractIn this work, a reinitialization procedure oriented to regularize the level set (LS) function field is presented. In LS approximations for two‐fluid flow simulations, a scalar function indicates the presence of one or another phase and the interface between them. In general, the advection of such function produces a degradation of some properties of the LS function, such as the smoothness of the transition between phases and the correct position of the interface. The methodology introduced here, denominated bounded renormalization with continuous penalization, consists of solving by the finite element method a partial differential equation with certain distinguishing properties with the aim of keeping the desirable properties of the LS function. The performance of the strategy is evaluated for several typical cases in one, two and three‐dimensional domains, for both the advection and the renormalization stages. Copyright © 2010 John Wiley & Sons, Ltd.
The end of slavery: Disease patterns and cultural behaviours of African Americans in Suriname
Authors: Okumura M. 
Published: May 2010

AbstractThere have been few bioanthropological studies related to African Americans, either slaves or free people. The results of an analysis of eight skeletons of African ancestry (five males and three females) acquired in Suriname at the end of the 19th century by Dr J. Spilzley and currently housed in the Duckworth Collection (University of Cambridge) are presented. Dental abrasion related to habitual pipe smoking was observed in four individuals, confirming the widespread use of pipe to smoke tobacco among slaves observed in other related sites. Our results indicate a very poor state of oral health for these individuals, with females presenting a higher frequency of dental carious lesions and antemortem tooth loss in comparison with males. The presence of cribra orbitalia in some individuals suggests, as observed in other diaspora skeletal series, individuals suffering from severe stress, caused by poor nutrition, infectious diseases, or both. Such appalling life conditions agree with many written records, which describe very harsh work conditions and very deprived diets. Our results, although based in a small sample, contribute to a better understanding of the cultural behaviours as well as the patterns of disease that afflicted the African Americans in Suriname in the 19th century. Copyright © 2010 John Wiley & Sons, Ltd.
Thiazolidinediones, cardiovascular disease and cardiovascular mortality: translating research into action for diabetes (TRIAD)
Authors: Bilik Dori , McEwen Laura N. , Brown Morton B. , Selby Joe V. , Karter Andrew J. , Marrero David G. , Hsiao Victoria C. , Tseng Chien‐Wen , Mangione Carol M. , Lasser Norman L. , Crosson Jesse C. , Herman William H. 
Published: May 2010

AbstractBackgroundStudies have associated thiazolidinedione (TZD) treatment with cardiovascular disease (CVD) and questioned whether the two available TZDs, rosiglitazone and pioglitazone, have different CVD risks. We compared CVD incidence, cardiovascular (CV), and all‐cause mortality in type 2 diabetic patients treated with rosiglitazone or pioglitazone as their only TZD.MethodsWe analyzed survey, medical record, administrative, and National Death Index (NDI) data from 1999 through 2003 from Translating Research Into Action for Diabetes (TRIAD), a prospective observational study of diabetes care in managed care. Medications, CV procedures, and CVD were determined from health plan (HP) administrative data, and mortality was from NDI. Adjusted hazard rates (AHR) were derived from Cox proportional hazard models adjusted for age, sex, race/ethnicity, income, history of diabetic nephropathy, history of CVD, insulin use, and HP.ResultsAcross TRIAD's 10 HPs, 1,815 patients (24%) filled prescriptions for a TZD, 773 (10%) for only rosiglitazone, 711 (10%) for only pioglitazone, and 331 (4%) for multiple TZDs. In the seven HPs using both TZDs, 1,159 patients (33%) filled a prescription for a TZD, 564 (16%) for only rosiglitazone, 334 (10%) for only pioglitazone, and 261 (7%) for multiple TZDs. For all CV events, CV, and all‐cause mortality, we found no significant difference between rosiglitazone and pioglitazone.ConclusionsIn this relatively small, prospective, observational study, we found no statistically significant differences in CV outcomes for rosiglitazone‐ compared to pioglitazone‐treated patients. There does not appear to be a pattern of clinically meaningful differences in CV outcomes for rosiglitazone‐ versus pioglitazone‐treated patients. Copyright © 2010 John Wiley & Sons, Ltd.
A computational study of CX (X = H, C, F, Cl) bond dissociation enthalpies (BDEs) in polyhalogenated methanes and ethanes
Authors: Shi Jing , He Jian , Wang Hua‐Jing 
Published: May 2010

AbstractBond dissociation enthalpies (BDEs) play a significant role in the photolysis of Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), which lead to the depletion of stratospheric ozone. In this work, we estimate the performance of Density Functional Theory (DFT) methods in calculating BDEs of CFCs and HCFCs, and find that DFTs are unreliable for this system. The reasons for the unreliability of DFT methods in this system are also concluded. Furthermore, composite ab initio methods G3 and G3B3 are demonstrated to accurately estimate BDEs of polyhalogenated lower alkanes. Eighty two experimental values from Comprehensive Handbook of Chemical Bond Energies (2007, 2nd edition) are re‐evaluated. Eight of them are doubted as having a deviation exceeding 20.0 kJ/mol between the theoretical and experimental values. We also systematically predict the BDEs in polyhalogenated methanes and ethanes. A further study is conducted on their relationships of structures and properties. Copyright © 2010 John Wiley & Sons, Ltd.
Assessment and validation of bronchodilation using the interrupter technique in preschool children
Authors: Mele Laura , Sly Peter D. , Calogero Claudia , Bernardini Roberto , Novembre Elio , Azzari Chiara , de Martino Maurizio , Lombardi Enrico 
Published: May 2010

AbstractObjectiveTo determine and validate a cut‐off value for bronchodilation using the interrupter resistance (Rint) in preschool children.Patients and MethodsRint was measured in 60 healthy children (age range 2.7–6.4 years) before and after salbutamol inhalation (200 µg). Four potential methods for assessing BDR were evaluated: percent change from baseline, percent change of predicted values, absolute change in Rint, and change in Z‐score. These cut‐off values, determined as the fifth percentile of the healthy group, were applied to children referred for the assessment of recurrent wheezing, classified on the basis of acute symptoms and/or abnormal chest examination into symptomatic (n = 60, age range 2.9–6.1 years) and asymptomatic (n = 60, age range 2.5–5.7 years) groups.ResultsThe cut‐off values for bronchodilation calculated in healthy children were: −32% baseline; −33% predicted; −0.26 kPa L−1 sec; and −1.25 Z‐scores. Assessing BDR in children with a history of wheezing by either a decrease in absolute Rint or a decrease in Z‐score gave sensitivity, specificity, negative predictive value, and positive predictive value all >80% for detecting children with current respiratory symptoms.ConclusionsBoth a decrease in Rint ≥0.26 kPa L−1 sec and a decrease in Z‐score of ≥1.25 are appropriate for assessing BDR in preschool children with a history of recurrent wheezing. As Z‐score is a more general solution, we recommend using a change in Z‐score to determine BDR in preschool children. Further longitudinal studies will be required to determine the clinical utility of measuring BDR in managing lung disease in such children. Pediatr Pulmonol. 2010; 45:633–638. © 2010 Wiley‐Liss, Inc.
An unusual cause of fever in a neonate: Influenza A (H1N1) virus pneumonia
Authors: Sert Ahmet , Yazar Abdullah , Odabas Dursun , Bilgin Hüseyin 
Published: May 2010

AbstractThe 2009 flu outbreak in humans, known as H1N1 influenza A, refers to influenza A due to a new H1N1 strain called swine‐origin influenza virus A. The signs and symptoms of novel influenza A (H1N1) virus infection are similar to those of seasonal influenza, and specific diagnostic testing is required to distinguish novel influenza A (H1N1) virus from seasonal influenza virus. It results in various degrees of infection, ranging from mild to severe to fatal. For the treatment of swine‐origin influenza virus A oseltamivir and zanamivir are effective in most cases. Influenza A (H1N1) pneumonia in the newborn has not been yet reported in the literature. To our knowledge, this is the first report of a neonate of pneumonia in which influenza A (H1N1) virus was isolated. Pediatr Pulmonol. 2010; 45:734–736. © 2010 Wiley‐Liss, Inc.
New surface contacts formed upon reductive lysine methylation: Improving the probability of protein crystallization
Authors: Sledz Pawel , Zheng Heping , Murzyn Krzysztof , Chruszcz Maksymilian , Zimmerman Matthew D. , Chordia Mahendra D. , Joachimiak Andrzej , Minor Wladek 
Published: May 2010

AbstractSurface lysine methylation (SLM) is a technique for improving the rate of success of protein crystallization by chemically methylating lysine residues. The exact mechanism by which SLM enhances crystallization is still not clear. To study these mechanisms, and to analyze the conditions where SLM will provide the optimal benefits for rescuing failed crystallization experiments, we compared 40 protein structures containing N,N‐dimethyl‐lysine (dmLys) to a nonredundant set of 18,972 nonmethylated structures from the PDB. By measuring the relative frequency of intermolecular contacts (where contacts are defined as interactions between the residues in proximity with a distance of 3.5 Å or less) of basic residues in the methylated versus nonmethylated sets, dmLys‐Glu contacts are seen more frequently than Lys‐Glu contacts. Based on observation of the 10 proteins with both native and methylated structures, we propose that the increased rate of contact for dmLys‐Glu is due to both a slight increase in the number of amine‐carboxyl H‐bonds and to the formation of methyl CH···O interactions. By comparing the relative contact frequencies of dmLys with other residues, the mechanism by which methylation of lysines improves the formation of crystal contacts appears to be similar to that of Lys to Arg mutation. Moreover, analysis of methylated structures with the surface entropy reduction (SER) prediction server suggests that in many cases SLM of predicted SER sites may contribute to improved crystallization. Thus, tools that analyze protein sequences and mark residues for SER mutation may identify proteins with good candidate sites for SLM.
Introduction to superstring cosmology
Authors: Kounnas C. 
Published: May 2010

AbstractThis is a summary of lectures in superstring cosmology given by the author at the CORFU 2009 School and Workshops “Theory – Cosmology – Phenomenology”, Corfu Institute, Greece, Sept. 6.–13, 2009. These lectures are based on some recent developments and ideas, in the framework of superstring theory, concerning the evolution and structure of the universe in (i) the very early “non‐geometric” cosmological era, (ii) the intermediate “radiation‐like” era and (iii) the late time cosmological era characterized by the electroweak phase transition.
The “landscape” of Pati–Salam heterotic superstring vacua
Authors: Rizos J. 
Published: May 2010

AbstractThe main aspects of a recently developed method for classification of heterotic superstring vacua in the Free Fermionic Formulation are presented. Using these techniques we classify a big number of approximately 1015 heterotic string vacua with Pati–Salam, SU(4) × SU(2)L × SU(2)R gauge symmetry with respect to their main phenomenological features as the number of families, Pati–Salam breaking Higgs, Standard Model Higgs doublets, additional triplets and exotic charge states. We identify an interesting subclass of these vacua, approximately one to one million, whose massless spectrum is completely free of fractionally charge states.
MBE growth of cubic AlN on 3C‐SiC substrate
Authors: Schupp Thorsten , Rossbach Georg , Schley Pascal , Goldhahn Rüdiger , Röppischer Marcus , Esser Norbert , Cobet Christoph , Lischka Klaus , As Donat Josef 
Published: May 2010

AbstractWe present our recent results on the growth of cubic AlN (001) layers by plasma assisted molecular beam epitaxy (PAMBE) using freestanding 3C‐SiC (001) substrate. For high‐quality c‐AlN layers reflection high‐electron energy diffraction (RHEED) patterns in all azimuths show RHEED patterns of the cubic lattice, hexagonal reflections are absent. High‐resolution X‐ray diffraction (HRXRD) measurements confirm the cubic structure of the c‐AlN layers with a lattice parameter of 4.373 Å. Atomic force microscopy (AFM) scans show an atomically smooth surface with a roughness of 0.2 nm RMS. Ellipsometry studies yield the dielectric function (DF) of c‐AlN from 1 to 10 eV. The direct gap is determined with 5.93 eV at room temperature, while the indirect one is below 5.3 eV (onset of adsorption). The high‐energy part of the DF is dominated by two transitions at 7.20 and 7.95 eV attributed to critical points of the band structure.
A growth model of cubic GaN microstripes grown by MOVPE: Vapour phase diffusion model including surface migration effects
Authors: Sukkaew Pitsiri , Sanorpim Sakuntam , Onabe Kentaro 
Published: May 2010

AbstractGrowth features of c‐GaN stripes grown by selective area metalorganic vapour phase epitaxy (SA‐MOVPE) on GaAs (001) substrates with stripe patterns aligned along [110] direction were analysed by vapour phase diffusion (VPD) model including surface migration effects from (111) facets. An addition of surface migration effects was found to improve the correlation between the simulation and experiment for the fill factors smaller than 0.5. The effects of the surface migration length (L) and the weight of surface migration contribution on the surface profile and the growth rate of the c‐GaN stripes were also analysed. An increase of L was found to strongly enhance the growth rate at the centre of c‐GaN stripes, while increasing the weight of contribution leads to the growth rate enhancement at the edges of the stripes. Our simulation demonstrated that the most probable values of L and the weight of contribution were 0.8 µm and 0.13, respectively. According to our simulation, mechanism of cubic‐to‐hexagonal structural phase transition is suggested as an incentive of the surface concentration profiles.