bluuebunny/crossref_metadata_2025 huggingface dataset:
Toolkits for automatic web service and GUI generation: KWATT
Authors: Qu Yenan , Erlebacher Gordon , Bollig Evan , Lafourcade Julien , Lapeyre‐Mirande Magali
Published: October 2009

In a previous paper, we explained how to translate an input script into a functional web service, independent of the script language. We extend this work by considering the automatic creation of graphical user interfaces to allow interaction between a user and the web service generated by KWATT. The key aspects of this work are three‐fold. First, comment lines inserted into the script provide hints to the interface generator regarding the interface widgets. Second, the structure of the GUI is encoded into an XML file, and third, a plugin architecture permits the interface to be the output in one of several languages. We present an example interface to illustrate the concepts. Copyright © 2009 John Wiley & Sons, Ltd.
Large‐scale numerical simulations of earthquake fault systems: illuminating the role of dilatational gravity in earthquake nucleation
Authors: Hayes T. J. , Tiampo K. F. , Rundle J. B.
Published: October 2009

Simulated slip histories and the associated gravity changes were generated using a large‐scale numerical simulation program for the San Andreas earthquake faults system, Virtual California. Statistical analysis of 55 000 years of these simulated earthquake cycles was investigated in order to study the usefulness of the dilatational gravity signal, those gravity changes due to a subsurface dilatational (or compressional) process, as a proxy for precursory stress and strain changes. Results indicate that the precursory dilatational gravity signal is dependent upon the fault orientation with respect to the tectonic loading plate velocity. This effect is interpreted as a consequence of preferential amplification of the shear stress or reduction of the normal stress, depending on the steady‐state regime investigated. Copyright © 2009 John Wiley & Sons, Ltd.
Implementation, performance, and science results from a 30.7 TFLOPS IBM BladeCenter cluster
Authors: Stewart Craig A. , Link Matthew , McCaulay D. Scott , Rodgers Greg , Turner George , Hancock David , Wang Peng , Saied Faisal , Pierce Marlon , Aiken Ross , Mueller Matthias S. , Jurenz Matthias , Lieber Matthias , Tillotson Jenett , Plale Beth A.
Published: October 2009

This paper describes Indiana University's implementation, performance testing, and use of a large high performance computing system. IU's Big Red, a 20.48 TFLOPS IBM e1350 BladeCenter cluster, appeared in the 27th Top500 list as the 23rd fastest supercomputer in the world in June 2006. In spring 2007, this computer was upgraded to 30.72 TFLOPS. The e1350 BladeCenter architecture, including two internal networks accessible to users and user applications and two networks used exclusively for system management, has enabled the system to provide good scalability on many important applications while being well manageable. Implementing a system based on the JS21 Blade and PowerPC 970MP processor within the US TeraGrid presented certain challenges, given that Intel‐compatible processors dominate the TeraGrid. However, the particular characteristics of the PowerPC have enabled it to be highly popular among certain application communities, particularly users of molecular dynamics and weather forecasting codes. A critical aspect of Big Red's implementation has been a focus on Science Gateways, which provide graphical interfaces to systems supporting end‐to‐end scientific workflows. Several Science Gateways have been implemented that access Big Red as a computational resource—some via the TeraGrid, some not affiliated with the TeraGrid. In summary, Big Red has been successfully integrated with the TeraGrid, and is used by many researchers locally at IU via grids and Science Gateways. It has been a success in terms of enabling scientific discoveries at IU and, via the TeraGrid, across the US. Copyright © 2009 John Wiley & Sons, Ltd.
A High Molecular Weight Donor for Electron Injection Interlayers on Metal Electrodes
Authors: Bröker Benjamin , Blum Ralf‐Peter , Beverina Luca , Hofmann Oliver T. , Sassi Mauro , Ruffo Riccardo , Pagani Giorgio A. , Heimel Georg , Vollmer Antje , Frisch Johannes , Rabe Jürgen P. , Zojer Egbert , Koch Norbert
Published: October 2009

The molecular donor 9,9′‐ethane‐1,2‐diylidene‐bis(N‐methyl‐9,10‐dihydroacridine) (NMA) has been synthesized, and its electronic properties were characterized both in solution using cyclic voltammetry and optical absorption spectroscopy, and at interfaces to metals with photoelectron spectroscopy (PES). The optical energy gap of NMA in solution increases by 0.10 eV when the compound is doubly oxidized. On the basis of quantum‐chemical calculations, this ipsochromic effect is rationalized by a change in geometry involving a severe torsion of the two acridinium moieties with respect to the central double bond, thus reducing conjugation upon oxidation. PES is reported for NMA deposited on Au(111), Ag(111), and Cu(111) single crystals. A decrease of the sample work function is observed that becomes larger with increasing molecular coverage and clearly exceeds values that would be expected for metal surface electron “push back” alone, confirming the electron donating nature of NMA. The growth mode of NMA on all three surfaces is almost layer‐by‐layer (Frank–van der Merwe). For tris(8‐hydroxyquinoline)aluminum (Alq3) deposited on top of a NMA‐modified Au(111) surface, the electron injection barrier (EIB) is reduced by 0.25 eV compared to that on pristine Au(111). Furthermore, the EIB reduction depends linearly on Φ of the donor‐modified Au(111) surface, adjustable by NMA precoverage. This enables continuous tuning of the EIB in organic electronic devices, in order to optimize device efficiency and performance.
Preparation of Cyanoguanidine and Ethylcyanamide Complexes of Ruthenium(II) and Osmium(II)
Authors: Albertin Gabriele , Antoniutti Stefano , Castro Jesús
Published: October 2009

Cyanoguanidine complexes [MCl{η1‐N≡CN(H)C(NH2)=NH}(η6‐p‐cymene)(PR3)]BPh4 [M = Ru, Os; PR3 = P(OEt)3, PPh(OEt)2, PPh2OEt, PiPr3] were prepared by treating compounds [MCl2(η6‐p‐cymene)(PR3)] with cyanamide N≡CNH2. Alternatively, complexes [MCl{η1‐N≡CN(H)C(NH2)=NH}(η6‐p‐cymene)(PR3)]BPh4 were prepared by treating [MCl2(η6‐p‐cymene)(PR3)] with cyanoguanidine. Diethylcyanamide complexes [MCl(N≡CNEt2)(η6‐p‐cymene)(PR3)]BPh4 were also obtained by treating [MCl2(η6‐p‐cymene)(PR3)] with an excess amount of N≡CNEt2. Complexes were characterised spectroscopically (IR, 1H, 31P, 13C NMR) and in the case of [RuCl{N≡CN(H)C(NH2)=NH}(η6‐p‐cymene){PPh(OEt)2}]BPh4 by X‐ray crystal structure determination.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Dynamic Enzymatic Kinetic Resolution of Methyl 2,3‐Dihydro‐1H‐indene‐1‐carboxylate
Authors: Pietruszka Jörg , Simon Robert Christian , Kruska Fabian , Braun Manfred
Published: October 2009

A new reaction setup for kinetic enzymatic resolution was established and is demonstrated for the case of the hydrolase‐catalysed conversion of methyl 2,3‐dihydro‐1H‐indene‐1‐carboxylate (1) in conjunction with a base‐catalysed racemisation. The system allows controlled racemisation, resulting in efficient dynamic kinetic resolution (DKR) of the title compound. Short reaction times and high enantioselectivities were obtained with CAL‐B and TBD (1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene). Compound (R)‐1 (ee 95 %) served as a starting material in a domino reaction that led to the biaryl indanyl ketone (R)‐8, a lead compound for novel inhibitors of peptidyl‐prolyl‐cis/trans‐isomerases, in 94 % ee. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Evaluation of a wind erosion model in a desert area of northern Asia by eddy covariance
Authors: Fratini Gerardo , Santini Monia , Ciccioli Paolo , Valentini Riccardo
Published: October 2009

For the first time, vertical fluxes of mineral dust measured by Eddy Covariance in two desert sites of Northern Asia have been used to test the performances of a wind erosion model in the field. Soil parameters required by the model were obtained through field and laboratory determinations. Model predictions and direct measurements have been compared. The main finding was that the direction of the horizontal wind relative to the orientation of nebkhas played a crucial role in determining the emission of particles in one of the investigated sites. Being unable to simulate such interaction, the model generally overestimated the actual emission. It provided, instead, reliable predictions (r2 = 0·87) when the wind direction was suitable in detaching loose erodible elements placed on nebkhas thanks to their normal orientation. Copyright © 2009 John Wiley & Sons, Ltd.
Control of sediment dynamics by vegetation as a key function driving biogeomorphic succession within fluvial corridors
Authors: Corenblit Dov , Steiger Johannes , Gurnell Angela M. , Tabacchi Eric , Roques Lydie
Published: October 2009

Riparian vegetation responds to hydrogeomorphic disturbances and environmental changes and also controls these changes. Here, we propose that the control of sediment erosion and deposition by riparian vegetation is a key geomorphological and ecological (i.e. biogeomorphic) function within fluvial corridors. In a 3 year study, we investigated the correlations between riparian vegetation and hydrogeomorphic dynamics along a transverse gradient from the main channel to the floodplain of the River Tech, France. Sediment erosion and deposition rates varied significantly along the transverse gradient as a function of the vegetation biovolume intercepting water flow. These effects, combined with the extremely strong mechanical resistance of pioneer woody structures and strong resilience of pioneer labile herbaceous communities, Populus nigra and Salix spp., explain the propensity of biogeomorphic succession (i.e. the synergy between vegetation succession and landform construction) to progress between destructive floods. This geomorphological function newly identified as an ‘ecosystem function’ per se encompasses the coupling of habitat and landform creation, maintenance and change with fundamental ecosystem structural changes in space and in time. Three different biogeomorphic functions, all related to the concept of ecosystem engineering, were identified: (i) the function of pioneer herbaceous communities to retain fine sediment and diaspores in the exposed zones of the active tract near the water resource, facilitating recruitment of further herbaceous and Salicacea species; (ii) the function of woody vegetation to drive the construction of forested islands and floodplains; and (iii) the function of stabilised riparian forests to act as ‘diversity reservoirs’ which can support regeneration after destructive floods. Overall, this study based on empirical data points to the fundamental importance of sediment flow control by pioneer riparian vegetation in defining fluvial ecosystem and landform organisation in time and in space. Copyright © 2009 John Wiley & Sons, Ltd.
Dried Blood Spot for Hepatitis C Virus Serology and Molecular Testing
Authors: Tuaillon Edouard , Mondain Anne-Marie , Meroueh Fadi , Ottomani Laure , Picot Marie-Christine , Nagot Nicolas , Van de Perre Philippe , Ducos Jacques
Published: October 2009

We investigated the performance of dried blood spots (DBS) in hepatitis C virus (HCV) diagnosis using modified commercial tests. Paired DBS and serum samples were collected from 200 patients: 100 patients with anti-HCV antibodies (anti-HCV), including 62 patients with detectable serum HCV RNA, and 100 patients without anti-HCV. The DBS sample consisted of three drops of approximately 50 μL of whole blood applied to a paper card, which was then stored at −20°C within 48 hours of collection. Using the Ortho HCV 3.0 enzyme-linked immunosorbent assay kit on DBS, we observed both a specificity and sensitivity of 99% in detecting anti-HCV. HCV RNA was detected on DBS in 60/62 (97%) patients with detectable serum HCV RNA, which was then successfully quantified in 55 samples (89%) using the Cobas TaqMan HCV test. A good correlation was observed between the DBS HCV RNA concentration and the serum level (

r2

= 0.95;

P

< 0.001). HCV genotyping was successfully performed on DBS samples, with a full concordance between the 14 paired DBS and serum samples (genotypes 1-4).

Conclusion:

This study presents DBS as a reliable alternative to serum specimens for detecting anti-HCV, quantifying HCV RNA and genotyping HCV. DBS may increase the opportunities for HCV testing and treatment follow-up in hard-to-reach individuals. (Hepatology 2010.)
Bile Salt Sequestration Induces Hepatic De Novo Lipogenesis Through Farnesoid X Receptor– and Liver X Receptorα–Controlled Metabolic Pathways in Mice
Authors: Herrema Hilde , Meissner Maxi , van Dijk Theo H. , Brufau Gemma , Boverhof Renze , Oosterveer Maaike H. , Reijngoud Dirk-Jan , Müller Michael , Stellaard Frans , Groen Albert K. , Kuipers Folkert
Published: October 2009

Diabetes is characterized by high blood glucose levels and dyslipidemia. Bile salt sequestration has been found to improve both plasma glycemic control and cholesterol profiles in diabetic patients. Yet bile salt sequestration is also known to affect triglyceride (TG) metabolism, possibly through signaling pathways involving farnesoid X receptor (FXR) and liver X receptor α (LXRα). We quantitatively assessed kinetic parameters of bile salt metabolism in lean C57Bl/6J and in obese, diabetic

db/db

mice upon bile salt sequestration using colesevelam HCl (2% wt/wt in diet) and related these to quantitative changes in hepatic lipid metabolism. As expected, bile salt sequestration reduced intestinal bile salt reabsorption. Importantly, bile salt pool size and biliary bile salt secretion remained unchanged upon sequestrant treatment due to compensation by

de novo

bile salt synthesis in both models. Nevertheless, lean and

db/db

mice showed increased, mainly periportally confined, hepatic TG contents, increased expression of lipogenic genes, and increased fractional contributions of newly synthesized fatty acids. Lipogenic gene expression was not induced in sequestrant-treated

Fxr

−/− and

Lxr

α−/− mice compared with wild-type littermates, in line with reports indicating a regulatory role of FXR and LXRα in bile salt–mediated regulation of hepatic lipid metabolism.

Conclusion:

Bile salt sequestration by colesevelam induces the lipogenic pathway in an FXR- and LXRα-dependent manner without affecting the total pool size of bile salts in mice. We speculate that a shift from intestinal reabsorption to

de novo

synthesis as source of bile salts upon bile salt sequestration affects zonation of metabolic processes within the liver acinus. (Hepatology 2010.)
Treatment of an extracapsular post‐renal biopsy pseudoaneurysm with ultrasound‐guided thrombin injection
Authors: Eng Mary , Vaughan Thomas E. , Woo Danny , Buell Joseph F.
Published: October 2009

Percutaneous renal biopsy is a convenient method to obtain allograft tissue for histologic evaluation. Vascular complications, such as arteriovenous (AV) fistula and pseudoaneurysm, following renal biopsy are well known, and they usually resolve without further intervention. When symptomatic, they should be treated. We present a patient on chronic anticoagulation who developed a pseudoaneurysm after percutaneous renal biopsy. Applying techniques learned in the management of femoral artery pseudoaneurysm, we treated our patient with ultrasound‐guided thrombin injection. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010
3D velocity quantification in the heart: Improvements by 3D PC‐SSFP
Authors: Rolf Marijn P. , Hofman Mark B.M. , Kuijer Joost P.A. , van Rossum Albert C. , Heethaar Rob M.
Published: October 2009

Purpose:

To test whether a 3D imaging sequence with phase contrast (PC) velocity encoding based on steady‐state free precession (SSFP) improves 3D velocity quantification in the heart compared to the currently available gradient echo (GE) approach.

Materials and Methods:

The 3D PC‐SSFP sequence with 1D velocity encoding was compared at the mitral valve in 12 healthy subjects with 3D PC‐GE at 1.5T. Velocity measurements, velocity‐to‐noise‐ratio efficiency (VNReff), intra‐ and interobserver variability of area and velocity measurements, contrast‐to‐noise‐ratio (CNR), and artifact sensitivity were evaluated in both long‐ and short‐axis orientation.

Results:

Descending aorta mean and peak velocities correlated well (r2 = 0.79 and 0.93) between 3D PC‐SSFP and 3D PC‐GE. At the mitral valve, mean velocity correlation was moderate (r2 = 0.70 short axis, 0.56 long axis) and peak velocity showed good correlation (r2 = 0.94 short axis, 0.81 long axis). In some cases VNReff was higher, in others lesser, depending on slab orientation and cardiac phase. Intra‐ and interobserver variability was generally better for 3D PC‐SSFP. CNR improved significantly, especially at end systole. Artifact levels did not increase.

Conclusion:

3D SSFP velocity quantification was successfully tested in the heart. Blood‐myocardium contrast improved significantly, resulting in more reproducible velocity measurements for 3D PC‐SSFP at 1.5T. J. Magn. Reson. Imaging 2009;30:947–955. © 2009 Wiley‐Liss, Inc.
Resovist enhanced MR imaging of the liver: Does quantitative assessment help in focal lesion classification and characterization?
Authors: Santoro Lucia , Grazioli Luigi , Filippone Antonella , Grassedonio Emanuele , Belli Giacomo , Colagrande Stefano
Published: October 2009

Purpose:

To improve characterization of focal liver lesions by a prospective quantitative analysis of percentage signal intensity change, in dynamic and late phases after slow (0.5 mL/s) Resovist administration.

Materials and Methods:

Seventy‐three patients were submitted on clinical indication to MR examination with Resovist. Signal intensity of 92 detected focal lesions (5–80 mm) were measured with regions of interest and normalized to paravertebral muscle in arterial, portal, equilibrium and T1/T2 late phases, by two observers in conference. Five values of percentage variations per patient were obtained and statistically evaluated.

Results:

The enhancement obtained on dynamic study is more suitable in hemangiomas and focal nodular hyperplasias than in adenomas and hepatocellular carcinomas. To discriminate benign versus malignant lesions on late‐phase‐T2‐weighted images, a cutoff = −26%, allowed sensitivity and specificity values of 97.4% and 97.7%, respectively. Area under the receiver operating characteristic (ROC) curve was 0.99. To differentiate hemangioma versus all other focal liver lesions, on late‐phase‐T1‐weighted images, a cutoff = +40% permitted sensitivity and specificity values of 90.5% and 98.0%, respectively. Area under the ROC curve was 0.98.

Conclusion:

Late phase quantitative evaluation after slow Resovist administration, allows to differentiate malignant from benign hepatic masses and hemangiomas from all the others focal liver lesions, on T2‐/T1‐weighted acquisitions, respectively. J. Magn. Reson. Imaging 2009;30:1012–1020. © 2009 Wiley‐Liss, Inc.
Diffusion‐weighted MR imaging of the liver at 3.0 Tesla using TRacking Only Navigator echo (TRON): A feasibility study
Authors: Ivancevic Marko K. , Kwee Thomas C. , Takahara Taro , Ogino Tetsuo , Hussain Hero K. , Liu Peter S. , Chenevert Thomas L.
Published: October 2009

Purpose:

To assess the feasibility of TRacking Only Navigator echo (TRON) for diffusion‐weighted magnetic resonance imaging (DWI) of the liver at 3.0T.

Materials and Methods:

Ten volunteers underwent TRON, respiratory triggered, and free breathing DWI of the liver at 3.0 Tesla (T). Scan times were measured. Image sharpness, degree of stair‐step and stripe artifacts for the three methods were assessed by two observers.

Results:

Mean scan times of TRON and respiratory triggered DWI relative to free breathing DWI were 34% and 145% longer respectively. In four of eight comparisons (two observers, two b‐values, two slice orientations), TRON DWI image sharpness was significantly better than free breathing DWI, but inferior to respiratory triggered DWI. In two of four comparisons (two observers, two b‐values), degree of stair‐step artifacts in TRON DWI was significantly lower than in respiratory triggered DWI. Degree of stripe artifacts between the three methods was not significantly different.

Conclusion:

DWI of the liver at 3.0T using TRON is feasible. Image sharpness in TRON DWI is superior to that in free breathing DWI. Although image sharpness of respiratory triggered DWI is still better, TRON DWI requires less scan time and reduces stair‐step artifacts. J. Magn. Reson. Imaging 2009;30:1027–1033. © 2009 Wiley‐Liss, Inc.
Measurement of R1 dynamics using sliding window‐DESPOT
Authors: Schulz Jessica , Korn Matthias , Woenne Eva C. , Umathum Reiner , Briel Andreas , Hengerer Arne , Semmler Wolfhard , Bock Michael
Published: October 2009

Purpose:

To measure longitudinal relaxation rate (R1) changes during contrast agent studies using a driven equilibrium single pulse observation of T1 (DESPOT) method with a sliding window (sw) acquisition.

Materials and Methods:

A sw‐DESPOT technique was implemented that uses several three‐dimensional (3D) image data sets to calculate R1 with a temporal resolution of only a single data set. Different sources of systematic errors were studied in simulations, and the technique was tested in a tumor‐bearing mouse using an intravascular contrast agent.

Results:

Consistent concentration distributions of the CA were calculated with a temporal resolution of 10 s.

Conclusion:

Sw‐DESPOT offers a precise and fast method to monitor the CA dynamics in 3D volumes. J. Magn. Reson. Imaging 2009;30:1163–1170. © 2009 Wiley‐Liss, Inc.
Cardiac function by MRI in congenital heart disease: Impact of consensus training on interinstitutional variance
Authors: Beerbaum Philipp , Barth Peter , Kropf Siegfried , Sarikouch Samir , Kelter‐Kloepping Andrea , Franke Diana , Gutberlet Matthias , Kuehne Titus
Published: October 2009

Purpose:

To investigate the impact of interinstitutional variance (=interobserver variance between institutions) for volumetric and flow cardiac MR (CMR) data and if training on image reading could improve bias.

Materials and Methods:

In a three‐center study, a total of 32 adults with repaired Tetralogy of Fallot and 23 controls underwent CMR using standardized protocols for ventricular volumes/mass (by transverse and short‐axis cine‐MRI) and pulmonary/aortic blood flow by velocity‐encoded MRI (VEC‐MRI). Data were analyzed blinded and independently in each institution by experienced readers. Interinstitutional variance was determined before/after training on consented guidelines for image analysis.

Results:

In patients, initial interinstitutional variability of right ventricular parameters was substantial but decreased by training. On transverse planes, variation coefficient for end‐diastolic/systolic volumes and ejection fraction decreased from 22%, 19%, and 19% to 7%, 10%, and 8%, respectively (P < 0.025). Left‐ventricular variation coefficients improved for end‐diastolic and stroke volumes from 8% and 15% to 4% and 6%, respectively (P < 0.007). For short‐axis volumetry training resulted in narrowed limits of confidence. Variability did not significantly change in the controls. There was no significant difference between transverse/short‐axis MRI. Interinstitutional variance for VEC‐MRI in patients/controls was low (<4%).

Conclusion:

Interinstitutional variance is an important source of variability in volumetric but not in flow CMR. Such variance can be reduced effectively by consented training. J. Magn. Reson. Imaging 2009;30:956–966. © 2009 Wiley‐Liss, Inc.
Liver parenchymal enhancement of hepatocyte‐phase images in Gd‐EOB‐DTPA‐enhanced MR imaging: Which biological markers of the liver function affect the enhancement?
Authors: Motosugi Utaroh , Ichikawa Tomoaki , Sou Hironobu , Sano Katsuhiro , Tominaga Licht , Kitamura Takatoshi , Araki Tsutomu
Published: October 2009

Purpose:

To clarify the factors that predict enhancement of the liver parenchyma in hepatocyte‐phase of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd‐EOB‐DTPA)‐enhanced MR imaging.

Materials and Methods:

Gd‐EOB‐DTPA–enhanced hepatocyte‐phase MR images of 198 patients with chronic liver diseases (Child‐Pugh class A in 112 patients, class B in 74 patients, and class C in 12 patients) were retrospectively analyzed. The hepatocyte‐phase images were obtained using fat‐suppressed T1‐weighted gradient‐echo images with a 3D acquisition sequence 10 min and 20 min after IV administration of Gd‐EOB‐DTPA (0.025 mmol/kg body weight). The quantitative liver–spleen contrast ratio (Q‐LSC) was calculated using the signal intensities of the liver and spleen. Serum albumin levels, total bilirubin levels, prothrombin activity, and the results of indocyanine green clearance tests (ICGs) were recorded and correlated with the Q‐LSC. Logistic regression analysis was performed to analyze which factors predict sufficient liver enhancement using a Q‐LSC of 1.5 as a cutoff value.

Results:

Only ICGs and Child‐Pugh classifications showed a statistically significant correlation with the Q‐LSC. Logistic regression analysis showed that ICGs were the only factors that accurately predicted liver enhancement on hepatocyte‐phase images.

Conclusion:

ICGs were found to be predictors of sufficient liver enhancement on hepatocyte‐phase images. J. Magn. Reson. Imaging 2009;30:1042–1046. © 2009 Wiley‐Liss, Inc.
Surface‐enhanced Raman scattering from polystyrene on gold clusters
Authors: Anema J. R. , Brolo A. G. , Felten A. , Bittencourt C.
Published: October 2009

Surface‐enhanced Raman scattering (SERS) constitutes a spectroscopic method of rapidly growing importance, and polystyrene is a widely used compound of great industrial importance. In this work, SERS data were obtained from polystyrene samples prepared by vapor deposition of gold and plasma‐induced polymerization of styrene gas. A thorough examination of this data is presented. The relationships between sample preparation parameters, gold‐cluster morphology, and SERS intensity were elucidated. Using Wilson's notation, vibrations were assigned to all bands between 250 and 1750 cm−1 in the ordinary Raman and SERS spectra of polystyrene. The correct assignment of these bands would be a significant achievement because they have been controversial in the literature for ∼30 years. Our assignments were made by reviewing the literature and comparing the assignments found there to spectral data acquired during this study; they were confirmed using density functional theory (DFT) calculations performed on the styrene monomer. The orientation of polystyrene's phenyl ring, relative to the gold surface, was determined. It has been suggested that reactions involving silver catalyze polystyrene degradation during SERS, but we found that silver is not necessary for the degradation to occur. Copyright © 2009 John Wiley & Sons, Ltd.
Epithelial differentiation of adipose‐derived stem cells for laryngeal tissue engineering
Authors: Long Jennifer L. , Zuk Patricia , Berke Gerald S. , Chhetri Dinesh K.
Published: October 2009

Objectives/Hypothesis:

One potential treatment option for severe vocal fold scarring is to replace the vocal fold cover layer with a tissue‐engineered structure containing autologous cells. As a first step toward that goal, we sought to develop a three‐dimensional cell‐populated matrix resembling the vocal fold layers of lamina propria and epithelium.

Study Design:

Basic science investigation.

Methods:

Adipose‐derived stem cells were cultured in fibrin hydrogels with various growth factors. At the end of the culture period, matrices were sectioned and labeled with immunomarkers to identify cell phenotype.

Results:

Adipose‐derived stem cells survived, attached, and populated three‐dimensional fibrin matrices. Under select conditions, a superficial layer of cells expressing epithelial marker proteins overlay a deeper mesenchymal cell layer.

Conclusions:

A three‐dimensional structure of fibrin and adipose‐derived stem cells was created as a prototype vocal fold replacement. Two segregated cell phenotypes occurred, producing a bilayered structure resembling epithelium over lamina propria. This preliminary work demonstrates the feasibility of tissue engineering to produce structures for vocal fold replacement. Laryngoscope, 2010
Chemical shift calibration of 1H MAS NMR liver tissue spectra exemplified using a study of glycine protection of galactosamine toxicity
Authors: Hong Young‐Shick , Coen Muireann , Rhode Cynthia M. , Reily Michael D. , Robertson Donald G. , Holmes Elaine , Lindon John C. , Nicholson Jeremy K.
Published: October 2009

High‐resolution 1H magic angle spinning (MAS) NMR spectroscopy is a useful tool for analysing intact tissues as a component of metabonomic studies. The effect of referencing MAS NMR spectra to the chemical shifts of glucose or to that or trimethylsilylpropionic acid on the resultant multivariate statistical models have been investigated. It is shown that referencing to known chemical shifts of either α‐glucose or β‐glucose in 1H MAS NMR‐based metabolic data of intact liver tissues is preferred. This has been exemplified in studies of galactosamine toxicity in the rat where co‐administration of glycine ameliorates the toxic response. This approach leads to better aligned sets of spectra and reduces the inter‐sample variability in multivariate statistical models. If glucose is not present in the tissue under study, then a number of alternative internal reference chemical shifts are presented. Finally, the chemical shift difference between that of the anomeric H1 proton of α‐glucose and residual water is confirmed as a suitable internal temperature calibration method. Copyright © 2009 John Wiley & Sons, Ltd.
Detection and quantification of flaws in structures by the extended finite element method and genetic algorithms
Authors: Waisman Haim , Chatzi Eleni , Smyth Andrew W.
Published: October 2009

This paper investigates the extended finite element method (XFEM)‐GA detection algorithm proposed by Rabinovich et al. (Int. J. Numer. Meth. Engng 2007; 71(9):1051–1080; Int. J. Numer. Meth. Engng 2009; 77(3):337–359) on elastostatic problems with different types of flaws. This algorithm is designed for non‐destructive assessment of structural components. Trial flaws are modeled using the XFEM as the forward problem and genetic algorithms (GAs) are employed as the optimization method to converge to the true flaw location and size. The main advantage of the approach is that XFEM alleviates the need for re‐meshing the domain at every new iteration of the inverse solution process and GAs have proven to be robust and efficient optimization techniques in particular for this type of problems.

In this paper the XFEM‐GA methodology is applied to elastostatic problems where flaws are considered as straight cracks, circular holes and non‐regular‐shaped holes. Measurements are obtained from strain sensors that are attached to the surface of the structure at specific locations and provide the target solution to the GA. The results show convergence robustness and accuracy provided that a sufficient number of sensors are employed and sufficiently large flaws are considered. Copyright © 2009 John Wiley & Sons, Ltd.
Adipocytokines in relation to Hodgkin lymphoma in children
Authors: Petridou Eleni Th. , Dessypris Nick , Panagopoulou Paraskevi , Sergentanis Theodoros N. , Mentis Alexios‐Fotios A. , Pourtsidis Apostolos , Polychronopoulou Sophia , Kalmanti Maria , Athanasiadou‐Piperopoulou Fani , Moschovi Maria
Published: October 2009

This case–control study aims to explore the association of serum adiponectin/leptin with childhood Hodgkin lymphoma (HL). Study participants were 75 children with histologically confirmed HL, registered in the Nationwide Registry for Childhood Haematological Malignancies and 75 age‐ and gender‐matched controls. Multiple conditional logistic regression analyses were performed, adjusting for sociodemographic and lifestyle parameters. Adiponectin levels were consistently higher among cases in all models with ORs >1.25; 95% CIs ranging from 0.9 to 1.8 and P‐values from 0.09 to 0.20. By contrast, there was no association of serum leptin with HL. In conclusion, elevated serum adiponectin might be a risk factor for childhood HL. Pediatr Blood Cancer 2010;54:311–315. © 2009 Wiley‐Liss, Inc.
Rapamycin (sirolimus) in tuberous sclerosis associated pediatric central nervous system tumors
Authors: Lam Catherine , Bouffet Eric , Tabori Uri , Mabbott Donald , Taylor Michael , Bartels Ute
Published: October 2009

Tuberous sclerosis complex (TSC) is associated with hamartomatous growths including subependymal giant cell astrocytomas (SEGAs). Since chemo‐radiation therapies offer scant benefit, oncologists had traditionally been little involved in managing SEGAs. Recent evidence demonstrating rapamycin efficacy in adults and children with TSC‐associated tumors foresee a practice change. We summarize our institutional experience and literature review that highlight potential benefits and hazards of rapamycin therapy, for TSC patients with SEGA, and other syndromal brain tumors. Pediatr Blood Cancer 2010;54:476–479. © 2009 Wiley‐Liss, Inc.
MGMT as a potential stratification marker in relapsed high‐grade glioma of children: The HIT‐GBM experience
Authors: Schlosser Sabrina , Wagner Sabine , Mühlisch Jörg , Hasselblatt Martin , Gerß Joachim , Wolff Johannes E.A. , Frühwald Michael C.
Published: October 2009

Background

Studies in adults with malignant glioma suggest MGMT methylation as a stratification marker. Similar data for children are sparse. We investigated the impact of MGMT methylation and expression on survival of children with high‐grade glioma (HGG) registered into the German HIT‐GBM database receiving temozolomide (TMZ) as part of their treatment (n = 21 relapsed, n = 4 primary).

Procedure

Twenty‐four patients were included retrospectively. Methylation specific PCR (MSP), calibrated combined bisulfite restriction analysis (COBRA), and immunohistochemistry (IHC) were applied. Survival analyses were performed by Kaplan–Meier and Cox proportional‐hazards models.

Results

MSP demonstrated DNA methylation in 77%. Patients with a methylated MGMT promoter had a sixfold longer median EFS (P = 0.015; 5.5 months vs. 0.9 months). Considering the results of calibrated COBRA, MGMT methylation was again associated with an elevated EFS (P = 0.05; 10.2 months vs. 2.6 months) and OS (P = 0.06; 18.7 months vs. 7.2 months) only if methylation was >14%. No difference in EFS and OS at all was noted between unmethylated and tumors methylated at low level (n = 9). Twenty‐two tumors were positive by IHC, 10 showed low MGMT expression (IHC score 0–4). We did not detect any difference in EFS and OS between moderate/high‐expressing tumors (IHC score 6–12) and those with low or no expression (IHC score 0–4).

Conclusion

DNA methylation, but not protein expression of MGMT was associated with an increased median EFS and OS of children with relapsed HGG. MGMT methylation status warrants prospective evaluation as a stratification marker for children with HGG. Pediatr Blood Cancer 2010;54:228–237. © 2009 Wiley‐Liss, Inc.
Retrospective analysis of non‐anaplastic peripheral T‐cell lymphoma in pediatric patients in Japan
Authors: Kobayashi Ryoji , Yamato Kazumi , Tanaka Fumiko , Takashima Yoshifumi , Inada Hiroko , Kikuchi Akira , Kumagai Masa‐aki , Sunami Shosuke , Nakagawa Atsuko , Fukano Reiji , Fujita Naoto , Mitsui Tetsuo , Tsurusawa Masahito , Mori Tetsuya
Published: October 2009

Background

Reports of non‐anaplastic peripheral T‐cell lymphoma (PTCL) in pediatric patients are relatively rare.

Procedure

We performed a retrospective analysis in patients with PTCL over an 18‐year period (1991–2008).

Results

We could analyze clinical data in 21 patients with non‐anaplastic PTCL; 10 were female and 10 male. Median age of onset was 11 years (range: 1–21 years). There were nine patients with PTCL, not otherwise specified (PTCL‐NOS); ten with extranodal NK/T‐cell lymphoma, nasal type; one with angioimmunoblastic T‐cell lymphoma; and one with subcutaneous panniculitis‐like T‐cell lymphoma. Initial lesions involved cervical lymph nodes in five patients, and the skin in five patients. In five patients, hemophagocytic syndrome (HPS) was the initial clinical feature. There were 12 patients with advanced stage disease (stages III and IV). Chemotherapy and radiation was administered in 18 and 2 patients, respectively. Among the two patients who did not receive chemotherapy and radiation, one patient died while being treated for HPS but another improved spontaneously. Although 5 patients relapsed, 18 of 21 patients remained alive without disease at last follow‐up. Five‐year overall survival rate was 85.2%.

Conclusions

Generally, the outcome results of conventional chemotherapy for high‐risk PTCL are poor in adult patients. However, the excellent results in our study suggest that PTCL of childhood is quite different from that of adulthood. Although this study is first report about PTCL of Asian children, the number of patients was small in this study. Larger studies are needed to confirm these findings. Pediatr Blood Cancer 2010;54:212–215. © 2009 Wiley‐Liss, Inc.
Effect of an epoxy octasilsesquioxane on the thermodegradation of an epoxy/amine system
Authors: Montero Belén , Ramírez Carmen , Rico Maite , Barral Luis , Díez Javier , López Joaquín
Published: October 2009

Polyhedral oligomeric silsesquioxanes (POSS®) can be added to thermoplastic and thermostable polymers to obtain hybrid materials with only a minor tendency to suffer ignition. The aim of the work reported was to analyse the influence of an octafunctional POSS® in the pyrolysis of an epoxy/amine system as well as during the combustion process. Thermal degradation of the modified materials, with respect to the unmodified ones, was analysed using thermogravimetric analysis. As the content of POSS® increased the stability improved and the char/ceramic yields were higher. The Kissinger–Akahira–Sunose method was applied to the modified blends and it showed a decrease in the activation energy with POSS® content. Empirical kinetic models, as well as generalized master plots, were applied to explain the degradation mechanism for ternary blends. The limiting oxygen index parameter was measured to analyse the fire retardancy effect of POSS®: it increased from 24.3 to 25.4% with the addition of 2.5 wt% of POSS®. The mechanism of thermal degradation of the hybrid materials based on an epoxy resin is affected by the presence of the octaepoxy POSS®. Only small amounts of POSS® are necessary to enhance the combustion resistance of the system. Copyright © 2009 Society of Chemical Industry
Nicotinic acid/laropiprant: a new lipid‐modifying therapy
Authors: Chaplin Steve , Evans Marc
Published: October 2009

Tredaptive is a combination of nicotinic acid and laropiprant for the treatment of dyslipidaemia and primary hypercholesterolaemia. In our New products review, Steve Chaplin discusses the clinical data relating to its efficacy and side‐effects, and Dr Marc Evans describes its place in therapy. Copyright © 2009 Wiley Interface Ltd
A bivariate survival model with compound Poisson frailty
Authors: Wienke A. , Ripatti S. , Palmgren J. , Yashin A.
Published: October 2009

A correlated frailty model is suggested for analysis of bivariate time‐to‐event data. The model is an extension of the correlated power variance function (PVF) frailty model (correlated three‐parameter frailty model) (J. Epidemiol. Biostat. 1999; 4:53–60). It is based on a bivariate extension of the compound Poisson frailty model in univariate survival analysis (Ann. Appl. Probab. 1992; 4:951–972). It allows for a non‐susceptible fraction (of zero frailty) in the population, overcoming the common assumption in survival analysis that all individuals are susceptible to the event under study. The model contains the correlated gamma frailty model and the correlated inverse Gaussian frailty model as special cases. A maximum likelihood estimation procedure for the parameters is presented and its properties are studied in a small simulation study. This model is applied to breast cancer incidence data of Swedish twins. The proportion of women susceptible to breast cancer is estimated to be 15 per cent. Copyright © 2009 John Wiley & Sons, Ltd.
Flexible modeling of longitudinal highly skewed outcomes
Authors: Chen Huichao , Manatunga Amita K. , Lyles Robert H. , Peng Limin , Marcus Michele
Published: October 2009

The analysis of data from epidemiologic and environmental studies presents challenges such as skewness of distribution, rounding and multiple measurements over time. To model trends over time based on repeated measurements, we propose a general latent model suitable for highly skewed data. The model assumes that the observed outcome is determined by an unobservable outcome that follows a Weibull distribution. To accommodate correlations among repeated responses over time, we introduce a general random effect from the power variance function (PVF) family of distributions, including the gamma distribution often employed in the literature. The resulting marginal likelihood has a closed form without resorting to numerical or approximation methods. We study estimation and hypothesis testing under these models, with different choices of random effect distributions. Simulation studies are conducted to evaluate their performance. Finally, we apply the proposed method to exposure data collected from the Michigan polybrominated biphenyl (MIPBB) study. Copyright © 2009 John Wiley & Sons, Ltd.
Nonlinear Marangoni instability of a liquid jet in the presence of electric field
Authors: Zakaria K. , Sirwah M. , Assaf A.
Published: October 2009

The work discusses the linear and nonlinear stability of cylindrical surface deformations between two incompressible fluids. The interface is carrying a uniform surface charge. The inner fluid is assumed to be a liquid jet. Both fluids are modeled as a special type of a Newtonian viscous fluid. Furthemore, the effect of surface adsorption is taken into account. Both fluids are assumed to be dielectric and the stability is discussed in the presence of a constant electric field in axial direction. The analysis is performed along the lines of a multiple scale perturbation expansion with additional slow time and space variables. The various stability criteria are discussed both analytically and numerically. The results are displayed in many plots showing the stability criteria in various parameter planes. The results show the dual role of the electric field and the negative rate of change of surface tension with the concentration of surfactant on the system stability, in both the linear and nonlinear steps. The nonlinear theory, when used to investigate the stability of liquid jet, appears accurately to predict new unstable regions.
Free convection gas flow near a vertical porous plate with heat sources/sinks
Authors: Toki C.J.
Published: October 2009

In this work, we study the two dimensional free‐convection boundary‐layer gas flow of a viscous and incompressible fluid near a moving porous, infinite and vertical plate (or wall) in the presence of heat sources/sinks. Exact solution of this problem is found with the help of Laplace transform technique. Analytical expressions of this solution for velocity, temperature, skin‐friction, and rate of heat transfer have been developed. The corresponding expressions for nonporous plate are discussed. The derived results are also discussed in details with the help of graphs for vertical air flows, in order to observe the effects of various governing parameters, such as the heat source/sink parameter. Furthermore, a comparison between the results obtained for porous plate and nonporous plate is illustrated in these graphs.
Analysis of Phospholipids in Rat Brain Using Liquid Chromatography–Mass Spectrometry
Authors: Norris Carmen , Fong Bertram , MacGibbon Alastair , McJarrow Paul
Published: October 2009

The brain is a lipid‐rich organ containing complex polar lipids including phospholipids (PLs) and sphingolipids. These lipids are involved in the structure and function of cell membranes in the brain. We developed a fast and efficient liquid chromatography–tandem mass spectrometry (LC–MS/MS) method to quantify five different classes of PLs [Choline glycerophospholipid (consists of phosphatidyl choline and plasmenyl choline in these samples), ethanolamine glycerophospholipid (consist of phosphatidyl ethanolamine and plasmenyl ethanolamine in these samples), phosphatidyl serine, phosphatidyl inositol, and sphingomyelin] in the brain tissues of 80‐day‐old Wistar rats. The PLs were extracted from rat brain using chloroform/methanol/water. After separation using a hydrophilic high performance liquid chromatography column, PL‐class‐specific fragmentation (head group identification) with a tandem mass spectrometer in positive ion mode was utilized to measure changes in the relative concentration of the five PL classes. The advantage of this approach was its improved specificity over previously reported LC–MS methods. The method had good repeatability (coefficient of variation 3–9%, excluding phosphatidyl inositol) and recovery (92–103%) and compared well with more laborious traditional methods.
Variation in the helminth community structure ofThrichomys pachyurus(Rodentia: Echimyidae) in two sub-regions of the Brazilian Pantanal: the effects of land use and seasonality
Authors: Simões R. , Gentile R. , Rademaker V. , D'Andrea P. , Herrera H. , Freitas T. , Lanfredi R. , Maldonado A.
Published: October 2009

The Pantanal is a large ecosystem located in South America. This preserved area is seasonally flooded due to abundant rainfall during the summer and the subsequent overflow of the Paraguai River. In this paper, we examine the helminth community structure in the wild rodentThrichomys pachyurusduring the wet and dry seasons in two locations of the preserved and cattle ranching areas in the Southern Pantanal. We identified 12 species of helminth, and, although we did not find any differences in species richness between locations within the Pantanal, we found that richness was higher during the wet season. Helminth species were largely aggregated in both farm locations and during seasons. The most common helminth species were more abundant during the dry season than during the wet season, which may have been due to the increased habitat availability and rodent population increase. The intensity of the infection also followed the same pattern for most helminths. The trichostrongylids (Heligmostrongylus crucifer,H. almeidaiandPudica cercomysi) were dominant at both farm locations. The land use of each area was not correlated with helminth diversity. However, species composition of the helminth community ofT. pachyurusdiffered between locations and may be correlated with environmental differences between the habitats. The seasonality of the Pantanal was highly correlated with helminth parasitism inT. pachyurus.