bluuebunny/crossref_metadata_2025_split huggingface dataset:
Convergence of steady and unsteady formulations for inviscid hovering rotor solutions
Authors: Allen C. B. 
Published: March 2003

AbstractAn upwind Euler solver is presented, and applied to multibladed lifting hovering rotor flow. These flows can be simulated as a steady case, in a blade‐fixed rotating co‐ordinate system. However, forward flight simulation will always require an unsteady solution. Hence, as a stepping stone in the development of a forward flight simulation tool, both explicit steady and implicit unsteady simulations of the same hovering case are presented. Convergence of the two approaches is examined and compared, in terms of residual history, cost, and solution evolution, as a means of both validating the unsteady formulation and considering implications for forward flight simulation. Consideration of the solution evolution and wake capturing shows that for hovering rotor cases, the unsteady and steady solutions are the same, but the unsteady solution is more expensive in terms of CPU time. It is also shown that for hover, the fewer real time‐steps taken per revolution the more efficient the implicit scheme is. However, this is a characteristic of the case, which results in smooth solution variation between time steps. It is also demonstrated that for rotary flow simulation, the global residual is not a useful quantity to assess convergence. The residual reaches a very low (constant in the implicit case) value while the solution is still evolving. Copyright © 2003 John Wiley & Sons, Ltd.
A Godunov method for the computation of erosional shallow water transients
Authors: Fraccarollo L. , Capart H. , Zech Y. 
Published: March 2003

AbstractA Godunov method is proposed for the computation of open‐channel flows in conditions of rapid bed erosion and intense sediment transport. Generalized shallow water equations govern the evolution of three distinct interfaces: the water free‐surface, the boundary between pure water and a sediment transport layer, and the morphodynamic bottom profile. Based on the HLL scheme of Harten, Lax and Van Leer (1983), a finite volume numerical solver is constructed, then extended to second‐order accuracy using Strang splitting and MUSCL extrapolation. Lateralisation of the momentum flux is adopted to handle the non‐conservative product associated with bottom slope. Computational results for erosional dam‐break waves are compared with experimental measurements and semi‐analytical Riemann solutions. Copyright © 2003 John Wiley & Sons, Ltd.
Rearrangement of the MOZ gene in pediatric therapy‐related myelodysplastic syndrome with a novel chromosomal translocation t(2;8)(p23;p11)
Authors: Imamura Toshihiko , Kakazu Naoki , Hibi Shigeyoshi , Morimoto Akira , Fukushima Yoko , Ijuin Ikuko , Hada Satoshi , Kitabayashi Issei , Abe Tatsuo , Imashuku Shinsaku 
Published: March 2003

AbstractIn this study, we examined a pediatric case of therapy‐related myelodysplastic syndrome (tMDS). The symptoms developed 17 months after treatment for acute myeloblastic leukemia (AML, M2 subtype according to the French–American–British [FAB] classification) involving a chromosome abnormality at t(8;21)(q22;q22). Upon diagnosis of tMDS, spectral karyotyping analysis detected a new chromosomal translocation at t(2;8)(p23;p11.2). In addition, fluorescence in situ hybridization analysis suggested a rearrangement in the monocytic leukemia zinc finger (MOZ) gene, located in the 8p11 region of chromosome 8. However, no partner gene on 2p23 could be identified. To our knowledge, this is the first report of tMDS associated with a rearrangement of the MOZ gene. MOZ‐linked fusion proteins such as MOZ‐CBP (CREB binding protein), MOZ‐TIF2 (transcriptional intermediary factor 2), and MOZ‐p300 (adenoviral E1A‐associated protein) are associated with AML chromosomal abnormalities at t(8;16)(p11;p13), inv(8)(p11q13), and t(8;22)(p11;q13), respectively, and are thought to account for leukemogenesis occurring through the aberrant regulation of histone acetylation. Through a similar mechanism, we believe that MOZ, fused to an unidentified partner gene at 2p23, may have caused an alteration in histone acetylation, resulting in the development of tMDS in this patient. © 2003 Wiley‐Liss, Inc.
Human prefrontal and sensory cortical activity during divided attention tasks
Authors: Loose Rainer , Kaufmann Christian , Auer Dorothee P. , Lange Klaus W. 
Published: March 2003

AbstractIn our natural environment, the ability to divide attention is essential since we attend simultaneously to a number of sensory modalities, e.g., to visual and auditory stimuli. In this study, functional magnetic resonance imaging (fMRI) was used to study brain activation while a divided attention task was performed. Brain activation was also assessed under selective attention. Fourteen healthy male subjects aged between 19 and 28 years underwent fMRI studies using gradient EPI sequences. Cingulate activation was evident in all attention tasks. Focusing attention on one modality (visual or auditory) increased the activity in the corresponding primary and secondary sensory area. When attention is divided between both modalities, the activation in the sensory areas is decreased, possibly due to a limited capacity of the system for controlled processing. Left prefrontal activation, however, was evident selectively during the divided attention task. The present results suggest that this area may be important in the execution of controlled processing when attention is divided between two sources of information. These results support the view that the prefrontal cortex is involved in the central executive system and controls attention and information flow. Hum. Brain Mapping 18:249–259, 2003. © 2003 Wiley‐Liss, Inc.
Novel ent‐Abietane Diterpenoids from Isodon eriocalyx var. laxiflora
Authors: Niu Xuemei , Li Shenghong , Zhao Qinshi , Mei Shuangxi , Lin Zhongwen , Sun Handong , Lu Yang , Wang Cheng , Zheng Qitai 
Published: March 2003

AbstractTwo novel ent‐abietane diterpenoids, 3α,20‐epoxy‐6β‐hydroxy‐1,7‐dioxo‐ent‐abiet‐15(17)‐en‐16‐oic acid (1) and ent‐abieta‐7,15(17)‐diene‐3β,16,18‐triol (2) were isolated from Isodon eriocalyx var. laxiflora. Their structures were determined by extensive spectroscopic analysis and confirmed by X‐ray crystallography. Compound 1 is an unprecedented example that establishes that a naturally occurring ent‐abietane diterpenoid can have an oxygenation pattern almost identical to those of 3α,20‐epoxy‐ent‐kaurane diterpenoids.
An Improved and Versatile Method for the Rapid Synthesis of Aryldihydrobenzofuran Systems by a Boron Tribromide‐Mediated Cyclization Reaction
Authors: Detterbeck Richard , Hesse Manfred 
Published: March 2003

AbstractBoron tribromide is presented as a highly reactive reagent that simultaneously allows the demethylation and fully diastereoselective cyclization of different precursor molecules, obtained by an aldol‐type reaction, to a series of hydroxylated aryldihydrobenzofuran systems in racemic form. The latter are often found as key structures in natural compounds of different classes. Syntheses of educts, which mainly took advantage of a versatile Rieche formylation, are also described.
Urinary N‐telopeptide levels in multiple myeloma patients, correlation with Tc‐99m‐sestaMIBI scintigraphy and other biochemical markers of disease activity
Authors: Alexandrakis M. G. , Kyriakou D. S. , Passam F. H. , Malliaraki N. , Vlachonikolis I. G. , Karkavitsas N. 
Published: March 2003

AbstractUrinary cross‐linked N‐telopeptide of type I collagen (NTx) has been reported to be a sensitive and specific marker of bone resorption in multiple myeloma (MM). In this study, we measured the levels of NTx in 30 newly diagnosed MM patients and 25 controls. We examined its association with the overall score of skeletal involvement measured by Tc‐99m‐MIBI scintigraphy and other biochemical markers of bone disease (tumour necrosis factor a (TNF‐a), serum calcium and creatinine). We further studied the correlation of NTx with the stage of disease (according to Durie–Salmon criteria) and bone marrow infiltration by plasma cells. High levels of NTx, bone marrow infiltration, TNF‐α, calcium and creatinine were noted at advanced stages of disease (p < 0.05). NTx and TNF‐a were found at significantly higher concentrations in patients with a high overall score (3 and 4) in Tc‐99m‐sestaMIBI in comparison to a low score (0, 1 and 2; p < 0.05). Positive correlations were found between NTx and TNF‐a, as well as between bone infiltration and TNF‐a or calcium. In conclusion, NTx is a useful marker for the monitoring of bone resorption in MM and correlates with imaging findings on Tc‐99m‐sestaMIBI and other biochemical markers of disease activity. Copyright © 2002 John Wiley & Sons, Ltd.
Molecular biologic comparison of new bone formation and resorption on microrough and smooth bioactive glass microspheres
Authors: Itälä A. , Välimäki V. V. , Kiviranta R. , Ylänen H. O. , Hupa M. , Vuorio E. , Aro H. T. 
Published: March 2003

AbstractIn a recent in vitro study, chemical microroughening of a bioactive glass surface was shown to enhance attachment of MG‐63 osteoblastic cells to glass. The current study was designed to delineate the effects of microroughening on the gene expression patterns of bone markers during osteogenesis and new bone remodeling on bioactive glass surface in vivo. With the use of a rat model of paired comparison, a portion of the medullary canal in the proximal tibia was evacuated through cortical windows and filled with microroughened or smooth bioactive glass microspheres. The primary bone‐healing response and subsequent remodeling were analyzed at 1, 2, and 8 weeks, respectively, by radiography, pQCT, histomorphometry, BEI‐SEM, and molecular biologic analyses. The expression of various genes for bone matrix components (type I collagen, osteocalcin, osteopontin, osteonectin) and proteolytic enzymes (cathepsin K, MMP‐9) were determined by Northern analysis of the respective mRNAs. Paired comparison showed significant differences in the mRNAs levels for specific bone matrix components at 2 weeks: osteopontin was significantly higher (p = .01) and osteonectin significantly lower (p = .05) in bones filled with microroughened microspheres than in those filled with smooth microspheres. Bones filled with microrough microspheres also showed significantly increased ratios of cathepsin K and MMP‐9 (both markers of osteoclastic resorption) to type I collagen (p = .02 and p = .02, respectively) at 2 weeks and a significantly increased expression of MMP‐9 at 8 weeks (p = .05). The pQCT, histomorphometric, and BEI‐SEM analyses revealed no significant differences in the pattern of bone‐healing response. Based on these results, microroughening of a bioactive glass surface could trigger temporal changes in the expression of specific genes especially by promoting the resorption part of new bone‐remodeling processes. Future studies are needed to evaluate if the observed changes of gene expression are directly related to the microrough surface of any biomaterial or are biomaterial specific. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 65B: 163–170, 2003
Rapid endothelialization of PhotoFix natural biomaterial vascular grafts
Authors: Carnagey John , Hern‐Anderson Diane , Ranieri John , Schmidt Christine E. 
Published: March 2003

AbstractTo date, no off‐the‐shelf graft has performed better than the autologous vessel in applications requiring small‐bore (< 6‐mm diameter) vascular grafts. Much research has been devoted to seeding endothelial cells on synthetic grafts to improve their long‐term clinical performance. One key challenge is the ability to retain the endothelium on the graft lumen for extended times. The goal of this research was to develop a process to seed endothelial cells inside a vascular graft and to quickly condition the cells so as to minimize their damage or removal under physiological flow. In addition, the use of PhotoFix® natural biomaterial grafts as an improved substrate for human umbilical vein endothelial cells has been evaluated. A motorized system that provides uniform cell seeding of a small‐diameter graft (4‐mm inner diameter, 10‐cm length) by automated radial rotation has been developed. The same system is subsequently adapted for gradual increases in flow rates to strengthen the endothelium, which ultimately was exposed to a final flow rate of 300 ml/min. This process is accomplished without graft transfer, decreasing risks of contamination and physical damage. Cell coverage and cell morphology were evaluated with the use of fluorescence microscopy and scanning‐electron microscopy to determine the effectiveness of the flow conditioning process. It was found that endothelial cells exhibit roughly 20–50% improved adhesion to PhotoFix vessels compared to fibrin‐treated polytetrafluoroethylene (PTFE) synthetic grafts. Flow conditioning for 6 h enhanced in vitro cell retention by 24% and 40% on PhotoFix and PTFE grafts, respectively. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 65B: 171–179, 2003
A cure for outdated capital budgeting techniques
Authors: Cotter James F. , Marcum Bill , Martin Dale R. 
Published: March 2003

AbstractIs your firm still using outdated capital budgeting techniques? They tend to be overly conservative in
evaluating alternatives—and may reject a project that should have been accepted. Instead, the authors
suggest a simulation method that will help you make better decisions. © 2003 Wiley Periodicals,
Inc.
Intracellular zinc fluxes associated with apoptosis in growth plate chondrocytes
Authors: Sauer Glenn R. , Smith Della M. , Cahalane Matthew , Wu Licia N.Y. , Wuthier Roy E. 
Published: March 2003

AbstractMatrix vesicles released by epiphyseal growth plate chondrocytes are known to contain a significant quantity of labile Zn2+. Zonal analysis of chicken metatarsal bones showed that the resting/proliferative region of the growth plate contained high levels of Zn2+ with significantly lower levels in the hypertrophic cartilage suggesting a loss of cellular Zn2+ as the chondrocytes mature. Intracellular labile Zn2+ was measured in primary cultures of growth plate chondrocytes by assay with the fluorescent Zn‐chelator toluenesulfonamidoquinoline (TSQ) and imaged by multi‐photon laser scanning microscopy (MPLSM) with the TSQ derivative zinquin. Short‐term exposure to Zn2+, both in the presence and absence of pyrithione resulted in significant increases in cytosolic Zn2+. Treatment with the membrane‐permeant Zn2+ chelator TPEN rapidly reduced the levels of labile Zn2+ and triggered apoptosis. Cytosolic Zn2+ levels were significantly reduced following 24‐h incubations with known inducers of chondrocyte apoptosis. The loss of intracellular Zn2+ was accompanied by a significant reduction in the cytosolic metal‐binding protein metallothionein. Examination of Zn2+‐treated cells with MPLSM showed uniformly higher zinquin fluorescence. Treatment of Zn2+‐loaded cells with TPEN quenched zinquin fluorescence confirming that the observed fluorescence in chondrocytes is due to the presence of intracellular Zn2+. A dose‐dependent increase in zinquin fluorescence was observed in cells treated with a range of Zn2+ concentrations. Short‐term treatment of cultured chondrocytes with apoptosis‐inducing chemicals resulted in transient increases in intracellular labile Zn2+. These results indicate that Zn2+ is mobilized from intracellular binding sites in the early stages of chondrocyte apoptosis and is subsequently lost from the cells. The early mobilization of Zn2+ provides a mechanism for its movement to matrix vesicles and the extracellular matrix. J. Cell. Biochem. 88: 954–969, 2003. © 2003 Wiley‐Liss, Inc.
Biochemical fractionation reveals association of DNA methyltransferase (Dnmt) 3b with Dnmt1 and that of Dnmt 3a with a histone H3 methyltransferase and Hdac1
Authors: Datta Jharna , Ghoshal Kalpana , Sharma Sudarshana M. , Tajima Shoji , Jacob Samson T. 
Published: March 2003

AbstractDe novo DNA methyltransferases, Dnmt3a and 3b, were purified by fractionation of S‐100 extract from mouse lymphosarcoma cells through several chromatographic matrices followed by glycerol density gradient centrifugation. Dnmt3a was separated from Dnmt3b and Dnmt1 in the first column, Q‐Sepharose whereas Dnmt3b co‐purified with Dnmt1 after further fractionation through Mono‐S and Mono‐Q columns and glycerol density gradient centrifugation. Following purification, the majority of de novo DNA methyltransfearse activity was associated with Dnmt3b/Dnmt1 fractions. By contrast, the fractions containing Dnmt3a alone exhibited markedly reduced activity, which correlated with diminished expression of this isoform in these cells. Histone deacetylase 1(Hdac1) cofractionated with Dnmt3a throughout purification whereas Hdac1 was separated from Dnmt3b/Dnmt1 following chromatography on Mono‐Q column. Dnmt3a purified through glycerol gradient centrifugation was also associated with a histone H3 methyltransferase (HMTase) activity whereas purified Dnmt3b/Dnmt1 was devoid of any HMTase activity. The activity of this HMTase was abolished when lysine 9 of N‐terminal histone H3 peptide was replaced by leucine whereas mutation of lysine 4 to leucine inhibited this activity only partially. This is the first report on the identification of a few key co‐repressors associated with endogenous Dnmt3a and of a complex containing Dnmt3b and a minor form of Dnmt1 following extensive biochemical fractionation. J. Cell. Biochem. 88: 855–864, 2003. © 2003 Wiley‐Liss, Inc.
Molecular mechanics force field parameterization of the fluorescent probe rhodamine 6G using automated frequency matching
Authors: Vaiana Andrea C. , Schulz Andreas , Wolfrum Jürgen , Sauer Markus , Smith Jeremy C. 
Published: March 2003

AbstractNovel single‐molecule fluorescence experimental techniques have prompted a growing need to develop refined computational models of dye‐tagged biomolecules. As a necessary first step towards useful molecular simulations of fluorescence‐labeled biomolecules, we have derived a force field for the commonly used dye, rhodamine 6G (R6G). A novel automated method is used that includes fitting the molecular mechanics potential to both vibrational frequencies and eigenvector projections derived from quantum chemical calculations. The method is benchmarked on a series of aromatic molecules then applied to derive new parameters for R6G. The force field derived reproduces well the crystal structure of R6G. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 632–639, 2003
Performance assessment of density‐functional methods for study of charge‐transfer complexes
Authors: Liao Meng‐Sheng , Lu Yun , Scheiner Steve 
Published: March 2003

AbstractVarious density functionals are applied to a number of weakly bound intermolecular π–π charge‐transfer (CT) complexes. Most functionals, including the recently developed mPWPW91 and mPW1PW91, grossly underestimate experimental excitation energies; good agreement is obtained only with the half‐and‐half hybrid BH&HLYP functional. PW91PW91 provides the best agreement with intermolecular distances measured in crystal, while the BH&HLYP values are about 0.1 Å too long. Various hybrid functionals with nonlocal exchange correction provide binding energies that compare favorably with the experimental heats of formation measured in solution. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 623–631, 2003
Conflict over natural resources among pastoralists in northern Kenya: a look at recent initiatives in conflict resolution
Authors: Berger Rachel 
Published: March 2003

AbstractThe paper describes the traditional relationship between pastoralism and the environment, and the institutions that underpin livelihood security and natural resource management. It identifies the circumstances that have led to pastoralism coming under threat and the resulting increase in inter‐tribal conflict over natural resources. The paper discusses how pastoralist institutions are changing and the role a third party can play in facilitating new institutional arrangements. Recent initiatives by non‐governmental organizations (NGOs) in capacity building for environmental management and peace building are examined for the extent to which these external interventions on conflict resolution can stabilize the pastoralist system. Copyright © 2003 John Wiley & Sons, Ltd.
Suggested role of the Golgi apparatus and endoplasmic reticulum for crucial sites of hepatitis C virus replication in human lymphoblastoid cells infected in vitro
Authors: Serafino Annalucia , Valli Maria Beatrice , Andreola Federica , Crema Annalisa , Ravagnan Giampietro , Bertolini Luisa , Carloni Guido 
Published: March 2003

AbstractIacovacci et al. [(1997a) Research in Virology 148:147–151] described that the euploid diploid cells, of the normal human bone marrow‐derived lymphoblastoid B‐cell line TO.FE., are susceptible to hepatitis C virus (HCV) infection and support long term virus production. Transmission electron microscopy described some steps of HCV replication cycle in this in vitro infected cellular system [Serafino et al. (1997) Research in Virology 148:153–159]. In the present study, in order to identify the intracellular sites involved in HCV replication, the ultrastructural changes associated with infection in TO.FE. cells were correlated with the subcellular localisation of structural and nonstructural viral proteins. Transmission electron microscopy and confocal microscopy data indicate that these viral proteins appeared located in the Golgi apparatus and endoplasmic reticulum, suggesting an active involvement of these compartments in viral assembly and morphogenesis. Furthermore, transmission and scanning electron microscopic observations on cultures infected chronically support the hypothesis that these cellular compartments may serve as starting sites of the morphological changes associated to viral infection and replication, leading to cell‐cell fusion, syncytia formation, and finally lysis of infected cells and virus release. J. Med. Virol. 70: 31–41, 2003. © 2003 Wiley‐Liss, Inc.
High‐density lipoprotein binding rate differs greatly between genotypes 1b and 2a/2b of hepatitis C virus
Authors: Kono Yoshihiro , Hayashida Kazuhiro , Tanaka Hirofumi , Ishibashi Hiromi , Harada Mine 
Published: March 2003

AbstractThe hepatitis C virus (HCV) virion is associated with lipoproteins and immunoglobulins in the sera of patients with chronic hepatitis C; however, an accurate binding rate of HCV to lipoproteins or immunoglobulins has not yet been elucidated. Therefore, the accurate binding rate of HCV to low‐density lipoproteins (LDL), high‐density lipoproteins (HDL), and immunoglobulins was measured quantitatively by a real‐time PCR assay. The immunoglobulin binding rate of HCV was found to be greater than 97.5% in most patients, as compared with an LDL binding rate of greater than 80% in most patients. In contrast, the HDL binding rate was greater than 98% in the genotype 2a/2b patients, while it varied in the genotype 1b patients. The genotype 2a/2b HCV not only had a higher LDL binding rate but also had a strikingly higher HDL binding rate than that of the genotype 1b HCV. These lipoprotein binding rates correlated neither to any patient's variables, including the serum apolipoprotein levels, nor to the viral load or the hypervariable region 1 (HVR 1) amino acid sequences. Most of the HCV virions in the sera of such patients have been shown to be associated simultaneously with immunoglobulins and LDL and/or HDL, but not exclusively. J. Med. Virol. 70: 42–48, 2003. © 2003 Wiley‐Liss, Inc.