bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serum ferritin underestimates liver iron concentration in transfusion independent thalassemia patients as compared to regularly transfused thalassemia and sickle cell patients
Authors: Pakbaz Zahra , Fischer Roland , Fung Ellen , Nielsen Peter , Harmatz Paul , Vichinsky Elliott 
Published: June 2007

AbstractSerum ferritin (SF) and liver iron concentration (LIC), as measured by SQUID biosusceptometry, were assessed in a convenience sample of transfusion independent thalassemia patients (nTx‐Thal, n = 26), regularly transfused thalassemia (Tx‐Thal, n = 89), or sickle cell patients (SCD, n = 45) to investigate the severity of iron overload and the relationship between SF and LIC in nTx‐Thal compared to SCD and Tx‐Thal. SF correlated with LIC (RS = 0.53, P < 0.001), but was found to be a poor predictor for LIC. SF was significantly lower (P < 0.001) in nTx‐Thal patients than in other groups, despite similar LIC values. The SF‐to‐LIC ratio was significantly lower in nTx‐Thal compared to Tx‐Thal and SCD patients (median of 0.32, 0.87, and 1.2, respectively: P < 0.001). Due to underestimation of LIC by ferritin levels, chelation treatment may be delayed or misdirected in patients with thalassemia intermedia. Pediatr Blood Cancer 2007;49:329–332. © 2007 Wiley‐Liss, Inc.
Loss of antibody titers and effectiveness of revaccination in post‐chemotherapy pediatric sarcoma patients
Authors: Yu Jennifer , Chou Alexander J. , Lennox Alison , Kleiman Phillip , Wexler Leonard H. , Meyers Paul A. , Gorlick Richard 
Published: June 2007

AbstractBackgroundLittle is known about the effects of chemotherapy on patient antibody titers to vaccine‐preventable infectious diseases; thus, there is no standard protocol for revaccinating post‐chemotherapy patients.ProceduresTo assess losses of detectable antibody titers due to chemotherapy, we retrospectively examined antibody titers for tetanus, varicella, measles, mumps, rubella, hepatitis B, and polio in 109 pediatric sarcoma patients. We also evaluated revaccination data to determine current practices and efficacy of revaccination. We limited our sample to osteosarcoma, Ewing sarcoma, and rhabdomyosarcoma patients to control for the chemotherapy regimen patients received.ResultsPatients had pre‐treatment detectable antibody titer that fell within the range of healthy children's antibody titers. However, 71% of patients had post‐chemotherapy negative titers for at least one infectious disease. Patients most commonly had negative titers for hepatitis B (64%). Few patients had negative titers for measles (14%), mumps (9%), rubella (4%), polio 1 (0%), polio 2 (2.9%), polio 3 (4.8%), tetanus (5%), or varicella (11%). Revaccinations most frequently administered were hepatitis B and polio.ConclusionsOur findings suggest that post‐chemotherapy patients may need to be revaccinated against certain vaccine‐preventable diseases including hepatitis B, tetanus, varicella, polio, measles, mumps, and rubella. Larger studies need to be performed to establish guidelines for revaccinating post‐chemotherapy pediatric patients. Pediatr Blood Cancer 2007;49:656–660. © 2007 Wiley‐Liss, Inc.
Polyester oligodiols by cationic AM copolymerization of L,L‐lactide and ε‐caprolactone initiated by diols
Authors: Baśko Małgorzata , Kubisa Przemyslaw 
Published: June 2007

AbstractCationic copolymerization of L,L‐lactide (LA) and ε‐caprolactone (CL) initiated by low molecular weight diols in the presence of acid catalyst gives corresponding copolyesters terminated at both ends with hydroxyl groups in practically quantitative yield. Copolymerization proceeds by Activated Monomer mechanism. LA is consumed preferentially and at the later stages of copolymerization the reaction mixture is enriched with CL. In spite of that, random distribution of both units is observed and end‐groups are mainly LA‐OH groups and not CL‐OH groups. This is explained by the fact that to reach high conversion of both comonomers the relatively long reaction times are required and at those conditions transesterification reaction becomes significant. Thus the microstructure of copolymers and the nature of the end‐groups is governed by transesterification rather then by the kinetics of comonomers incorporation. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3090–3097, 2007
RGD peptide grafted biodegradable amphiphilic triblock copolymer poly(glutamic acid)‐b‐poly(L‐lactide)‐b‐poly(glutamic acid): Synthesis and self‐assembly
Authors: Deng Chao , Chen Xuesi , Sun Jing , Lu Tiancheng , Wang Wenshou , Jing Xiabin 
Published: June 2007

AbstractA novel amphiphilic biodegradable triblock copolymer (PGL‐PLA‐PGL) with polylactide (PLA) as hydrophobic middle block and poly(glutamic acid) (PGL) as hydrophilic lateral blocks was successfully synthesized by ring‐opening polymerization (ROP) of L‐lactide (LA) and N‐carboxy anhydride (NCA) consecutively and by subsequent catalytic hydrogenation. The results of cell experiment of PGL‐PLA‐PGL suggested that PGL could improve biocompatibility of polyester obviously. The copolymer could form micelles of spindly shape easily in aqueous solution. The pendant carboxyl groups of the triblock copolymer were further activated with N‐hydroxysuccinimide and combined with a cell‐adhesive peptide GRGDSY. Incorporation of the oligopeptide further enhanced the hydrophilicity and led to formation of spherical micelles. PGL‐PLA‐PGL showed better cell adhesion and spreading ability than pure PLA and the GRGDSY‐containing copolymer exhibited even further improvement in cell adhesion and spreading ability, indicating that the copolymer could find a promising application in drug delivery or tissue engineering. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3218–3230, 2007
Integrated mechanism for the morphological structure development in HDPE melt‐blown and machine‐direction‐oriented films
Authors: Bafna Ayush , McFaddin Douglas , Beaucage Gregory , Merrick‐Mack Jean , Mirabella Francis M. 
Published: June 2007

AbstractThe morphologies of a series of blown films and machine‐direction‐oriented (MDO) films, all produced from high density polyethylene, were characterized. In the blown film process, the crystalline morphology develops while the melt is under extensional stress. In the MDO process, drawing takes place in the solid state and deforms the crystalline morphology of the starting film. The films were characterized by wide‐angle X‐ray scattering (WAXS), small‐angle X‐ray scattering (SAXS) and atomic force microscopy to determine the lamellar morphology. The effect of the type of deformation on the lamellar morphology was studied and relationships were developed between the lamellar and polymer chain morphology using SAXS and WAXS. Blown and MDO films were found to have very different morphologies. However, an integrated mechanism was developed linking the sequential events in the deformation and morphology development in blown and MDO films. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1834–1844, 2007
Subacute proteome changes following traumatic injury of the developing brain: Implications for a dysregulation of neuronal migration and neurite arborization
Authors: Kaindl Angela M. , Zabel Claus , Stefovska Vanya , Lehnert Ron , Sifringer Marco , Klose Joachim , Ikonomidou Chrysanthy 
Published: June 2007

AbstractTraumatic brain injury (TBI) is a major cause of morbidity and mortality among children and adolescents. To gain insight into developmental events influenced by TBI, we analyzed subacute mouse brain proteome changes in a percussion head trauma model at P7 ipsi‐ and contralateral to the site of injury. The comparison of brain proteomes of trauma mice and controls revealed reproducible changes in the intensity of 28 proteins (30 protein spots) in response to trauma. The changes detected suggest that TBI leads to apoptosis, inflammation, and oxidative stress. These changes were consistent with our results of histological and biochemical evaluation of the brains which revealed widespread apoptotic neurodegeneration, microglia activation, and increased levels of protein carbonyls. Furthermore, we detected changes in proteins involved in neuronal migration as well as axonal and dendritic growth and guidance, suggesting interference of trauma with these developmental events.
Crystal structure of calcium binding protein‐1 from Entamoeba histolytica: A novel arrangement of EF hand motifs
Authors: Kumar Shivesh , Padhan Narendra , Alam Neelima , Gourinath S. 
Published: June 2007

AbstractCalcium plays a pivotal role in the pathogenesis of amoebiasis, a major disease caused by Entamoeba histolytica. Several EF‐hand containing calcium‐binding proteins (CaBPs) have been identified from E. histolytica. Even though these proteins have very high sequence similarity, they bind to different target proteins in a Ca2+ dependent manner, leading to different functional pathways (Yadava et al., Mol Biochem Parasito 1997;84:69–82; Chakrabarty et al., J Biol Chem 2004;279:12898–12908) The crystal structure of the Entamoeba histolytica calcium binding protein‐1 (EhCaBP1) has been determined at 2.4 Å resolution. The crystals were grown using MPD as precipitant and they belong to P63 space group with unit cell parameters of a = 95.25 Å, b = 95.25 Å, c = 64.99 Å. Only two out of the four expected EF hand motifs could be modeled into the electron density map and the final model refined to R factor of 25.6% and Free_R of 28%. Unlike CaM, the first two EF hand motifs in EhCaBP1 are connected by a long helix and form a dumbbell shaped structure. Owing to domain swapping oligomerization three EhCaBP1 molecules interact in a head to tail manner to form a triangular trimer. This arrangement allows the EF‐hand motif of one molecule to interact with that of an adjacent molecule to form a two EF‐hand domain similar to that seen in the N‐terminal domain of the NMR structure of CaBP1, calmodulin and troponin C. The oligomeric state of EhCaBP1 results in reduced flexibility between domains and may be responsible for the more limited set of targets recognized by EhCaBP1. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Tilted properties of the 67–78 fragment of α‐synuclein are responsible for membrane destabilization and neurotoxicity
Authors: Crowet Jean‐Marc , Lins Laurence , Dupiereux Ingrid , Elmoualija Benaïssa , Lorin Aurélien , Charloteaux Benoit , Stroobant Vincent , Heinen Ernst , Brasseur Robert 
Published: June 2007

Abstractα‐Synuclein is a 140 residue protein associated with Parkinson's disease. Intraneural inclusions called Lewy bodies and Lewy neurites are mainly composed of α‐synuclein aggregated into amyloid fibrils. Other amyloidogenic proteins, such as the β amyloid peptide involved in Alzheimer's disease and the prion protein (PrP) associated with Creuztfeldt‐Jakob's disease, are known to possess “tilted peptides”. These peptides are short protein fragments that adopt an oblique orientation at a hydrophobic/hydrophilic interface, which enables destabilization of the membranes. In this paper, sequence analysis and molecular modelling predict that the 67–78 fragment of α‐synuclein is a tilted peptide. Its destabilizing properties were tested experimentally. The α‐synuclein 67–78 peptide is able to induce lipid mixing and leakage of unilamellar liposomes. The neuronal toxicity, studied using human neuroblastoma cells, demonstrated that the α‐synuclein 67–78 peptide induces neurotoxicity. A mutant designed by molecular modelling to be amphipathic was shown to be significantly less fusogenic and toxic than the wild type. In conclusion, we have identified a tilted peptide in α‐synuclein, which could be involved in the toxicity induced during amyloidogenesis of α‐synuclein. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Synthesis and mass spectrometry of benzoxazoline, dimethyloxazoline and 4‐phenyloxazoline derivatives of polyunsaturated fatty acids
Authors: Kangani Cyrous O. , Kelley David E. , Evans Rhobert W. 
Published: June 2007

AbstractCyclic nitrogen moieties have proved to be of great value for the mass spectrometric location of double bonds in polyunsaturated fatty acids. However, their synthesis has traditionally required long reaction times and/or high temperatures. Recently, we introduced a one‐pot, high‐yield, mild and efficient method for the synthesis of various fatty acid amide derivatives. We have now extended this procedure to include the synthesis of benzoxazoline, dimethyloxazoline and 4‐phenyloxazoline analogs of a series of fatty acids containing 18 to 22 carbon atoms and 0 to 6 double bonds. A comparison of the mass spectral properties of the three derivatives of these saturated and unsaturated fatty acids is described. Copyright © 2007 John Wiley & Sons, Ltd.
Feedback control with signal transmission after‐effects
Authors: Gao Huijun , Lam James , Chen Tongwen , Wang Changhong 
Published: June 2007

AbstractIn many practical systems, the physical plant, controller, sensor, and actuator are difficult to be located at the same place, and thus signals are required to be transmitted from one place to another. One immediate problem arising from such situations is that signals may exhibit after‐effect phenomena during their transmission. In this paper, we present a new model to characterize the state‐feedback control systems with signal transmission after‐effects, which deals with the transmission after‐effects from sensor to controller and from controller to actuator separately. Analysis and synthesis results based on this new model are established by using a Lyapunov–Krasovskii approach. Numerical simulations are provided to illustrate the usefulness of the theoretical results. Copyright © 2007 John Wiley & Sons, Ltd.
Electric‐Field‐Directed Assembly of Biomolecular‐Derivatized Nanoparticles into Higher‐Order Structures
Authors: Dehlinger Dietrich A. , Sullivan Benjamin D. , Esener Sadik , Heller Michael J. 
Published: June 2007

AbstractMultilayered structures composed of biomolecule‐derivatized nanoparticles can be fabricated by electric‐field‐directed self‐assembly. A microelectrode‐array device facilitates the rapid parallel electrophoretic transport and binding of biotin and streptavidin fluorescent nanoparticles to specific sites on the microarray. Control of the current, voltage, and activation time of each of the 400‐microarray electrodes allows a combinatorial approach to optimize nanoparticle binding. Under optimal conditions, nanoparticle layers form within 15 s of microelectrode activation, and the directed assembly of more than 50 alternate layers of nanoparticles is complete within an hour. The final multilayered structures are removed from the support by a relatively simple lift‐off process. The electric‐field process allows the parallel patterned assembly of multilayer structures using extremely low concentrations of nanoparticles and produces minimal nonspecific binding to unactivated sites. These results are significant for the development of rapid, maskless nanofabrication and hierarchical integration of biomolecular‐derivatized nanocomponents into higher‐order materials and devices.
Eine Dichtegleichung für Schwingungssysteme bei gleichzeitigen kontinuierlichen und diskreten stochastischen Erregungen
Authors: Renger A. 
Published: June 2007

AbstractFür Schwingungssysteme, die gleichzeitig durch Gaußsches Weißes Rauschen und durch Impulsprozesse erregt werden, wird eine partielle Integrodifferentialgleichung für die Wahrscheinlichkeitsdichte der Systemantwort hergeleitet. Die Gleichung kann als Verallgemeinerung der Fokker‐Planck‐Gleichung auf Markov‐Prozesse, die keine Diffusionsprozesse darstellen, interpretiert werden. Am Beispiel des einfachen Tiefpasses sowie eines durch shot‐noise in Längsrichtung parametererregten Balkens werden erste Untersuchungen auf der Grundlage dieser Gleichung vorgeführt.
Behandlung eines stochastischen Steuerproblems mit Hilfe eines abstrakten Maximumprinzips von Spremann
Authors: Müller H.‐O. 
Published: June 2007

AbstractIn der Arbeit wird mit Hilfe des abstrakten Optimalitätsprinzips von Spremann ein stochastisches Maximumprinzip für Steuerprobleme bewiesen, deren Bewegungsgleichung die Gestalt

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über einem festen Zeitintervall [t0, t1] besitzt. Z ist dabei ein stochastischer Prozeß, der die zufälligen Parameter des Systems repräsentiert, und die Steuerung U wird in Abhängigkeit von den unvollständigen Beobachtungen der Prozesse φ, Z und des Wiener‐Prozesses W gewählt. Das Maximumprinzip hat die Form einer Ungleichung der bedingten Erwartung einer Hamilton‐Funktion bezüglich der σ‐Algebra der vorliegenden Informationen. Die Hamilton‐Funktion entspricht dabei strukturell dem deterministischen Fall.
Unsteady Combined Convection from an Isothermal Circular Cylinder
Authors: Katagiri M. , Pop I. 
Published: June 2007

AbstractAn investigation is made of the heat transfer by combined free and forced convection from an isothermal circular cylinder in an unsteady stream of viscous incompressible fluid. Numerical solutions of unsteady boundary layer equations are sought by employing the local non‐similarity solution method (see Ref. [7]), together with difference‐differential method. In particular, the development of the boundary layer flow, the skin friction and heat transfer coefficients at the front stagnation point are examined. The numerical solution is compared with previous numerical work on the problem.
Zur Struktur der Gleichungen der Elastokinetik und Elastostabilität
Authors: Bufler H. 
Published: June 2007

AbstractAusgehend von D'Alembertschen Prinzip und seinen für eine gemischte Formulierung erforderlichen Erweiterungen werden die entsprechenden Variationsgleichungen für die inkrementellen Größen entwickelt. Diese dienen als Grundlage für die approximative Lösung kontinuierlicher Schwingungs‐ und Stabilitätsaufgaben und führen zu den Lagrangeschen Gleichungen 2. Art des diskreten Ersatzsystems und ihren Erweiterungen. Die Symmetrien der dabei entstehenden Matrizen beruhen auf der Potentialeigenschaft der Operatoren der nichtlinearen Ausgangsdifferentialgleichungen.
Random Vibration and Stability of a Linear Parametrically Excited Oscillator
Authors: Ariaratnam S. T. , Tam D. S. F. 
Published: June 2007

AbstractThe random vibration and stability of a linear second‐order oscillator subjected to both parametric and forced excitations of small intensity are investigated. Using a method of stochastic averaging, the steady‐state values of the response amplitudes as well as conditions for moment and sample stability are obtained. The first‐passage problem for envelope crossing is also examined.
Free Convection Boundary Layer on a Flat Plate due to Small Fluctuations in Surface Temperature
Authors: Muhuri P. K. , Gupta A. S. 
Published: June 2007

AbstractUsing the method of matched asymptotic expansions the unsteady free convection boundary layer flow past a vertical flat plate is obtained when the plate temperature oscillates about a non‐zero mean. It is found that when the Prandtl number is not unity, the solution far downstream reveals a double boundary layer, the inner layer being a shear layer having a double‐deck structure. The skin‐friction has a phase lag π/4 and the wall heat transfer has a phase lead π/4 over that of the surface temperature oscillations.
Weitere Konvergenzkriterien für das Gauß‐Seidel‐Verfahren
Authors: Albrand H.‐J. 
Published: June 2007

AbstractIn dieser Arbeit werden Zeilen‐ und Spaltensummennormen zweier Iterationsmatrizen exakt berechnet und naheliegende Abschätzungen de Matrixnormen und des Spektralradius hergeleitet. Diese Abschätzungen ergeben einige einfach strukturierte Konvergenzkriterien für das Gauß‐Seidel‐Verfahren zur Lösung linearer Gleichungssysteme. Die Arbeit enthält ferner einige Aussagen zur Schärfe der Abschätzungen, über Zusammenhänge zwischen den Abschätzungen, Fehlerabschätzungen und instruktive Beispiele.
Vergleich von Algorithmen für die Anpassung des Rechenmodells einer schwingungsfähigen elastomechanischen Struktur an Versuchswerte
Authors: Natke H. G. 
Published: June 2007

AbstractDie Systemanalyse elastomechanischer Strukturen, basierend auf den Konstruktionszeichnungen, ergibt das Rechenmodell als Annäherung an die reale Struktur. Im allgemeinen weichen die mit Hilfe des Rechenmodells errechneten Werte von den Versuchswerten ab. Die Verbesserung des Rechenmodells durch die Korrektur der in Submatrizen zerlegten Steifigkeits‐ (Nachgiebigkeits‐)matrix anhand von gemessenen Eigenfrequenzen, Eigenfrequenzen und Eigenschwingungsformen, harmonischen Kräften und/oder zugehörigen dynamischen Antworten wird für ungedämpfte Strukturen behandelt. Die verschiedenen zur Korrektur verwendeten Versuchswerte führen auf unterschiedliche Verlustfunktionen für die Methode der gewichteten kleinsten Fehlerquadrate. Die sich ergebenden unterschiedlichen Anpassungsverfahren werden global miteinander verglichen. Als günstig erscheint die Verwendung von gemessenen stationären Antworten der Struktur und der eingeleiteten harmonischen Kräfte für die Verbesserung des Rechenmodells über die Anpassung der Kraftvektoren.
Auswirkungen von Rundungen und Näherungen bei einer Klasse iterativer Verfahren
Authors: Wildenauer P. 
Published: June 2007

AbstractDer Einfluß auf das Konvergenzverhalten einer Iterationsfolge durch Rundungs‐ und evtl. Näherungsfehler, die bei jedem Iterationsschritt auftreten, wird untersucht. Dabei werden die zulässigen maximalen Fehler bei den einzelnen Iterationsschritten nicht als konstant vorausgesetzt. Die angegebenen Aussagen (Satz 1, Lemmata 2, 3) zur Fehler‐Analyse eignen sich für Verfahren, die in einem Bereich globale Konvergenz ergeben. Für diese ermöglichen sie die Fehler‐Analyse für jede in diesem Bereich gestartete Iterationsfolge. Die allgemeinen Sätze werden auf das Banachsche‐ und Newtonsche Iterationsverfahren angewandt. Die Arbeit ermöglicht eine wesentliche Einsparung von Rechenzeit. wenn die Approximationsgenauigkeit mit der Zahl der Iterationen gesteigert wird (siehe Abschnitt 5).
Monotone Difference Schemes for Diffusion‐Convection Problems
Authors: Stoyan Gisbert 
Published: June 2007

AbstractMonotone difference schemes are considered (that is schemes for which the maximum principle holds) for diffusion‐convection problems modelled by (1) or by corresponding parabolic and two‐dimensional elliptic equations. The diffusion/convection ratio may be small or great, and a continuous connection is created between these two cases. For instance, in one of the variants a continuous transition is achieved from the Crank‐Nicholson‐scheme (applied if convection is zero) and a symmetric, second order Wendroff scheme (for the pure transport equation.) Numerical results for (1) show the efficiency of the method.
On a Griffith Crack at the Interface of two Bonded Dissimilar Elastic Wedges
Authors: Srivastava K. N. , Palaiya R. M. , Choudhary Arati 
Published: June 2007

AbstractThe stress field in the vicinity of a Griffith crack located at the interface of two bonded dissimilar wedges is determined. A systematic use of inverse Mellin transform reduces the problem to that of solving a set of simultaneous dual integral equations and this system in turn is shown to be equivalent to a Riemann boundary value problem with closed form solution. The particular case in which the crack is opened by constant pressure is discussed in detail. Expressions for the stress intensity factors at the crack tip are derived.
Lagrange‐Formalismus für diskrete elektromechanische Systeme
Authors: Maisser P. , Steigenberger J. 
Published: June 2007

AbstractEs werden notwendige und hinreichende Bedingungen für die Existenz eines Lagrangeschen Models diskreter elektromechanischer Systeme (charakterisiert durch Kopplung von Starrkörpermechanik und Kirchhoff‐Theorie) formuliert. Bei Erfülltsein dieser Bedingungen werden das Lagrange‐Modell (Lagrange ‐ und Dissipationsfunktion) konstruiert und die Lagrangeschen Gleichungen explizit angegeben.