bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of micronuclei in peripheral blood lymphocytes of traffic wardens: Effects of exposure, metabolic genotypes, and inhibition of excision repair in vitro by ARA‐C
Authors: Leopardi P. , Zijno A. , Marcon F. , Conti L. , Carere A. , Verdina A. , Galati R. , Tomei F. , Baccolo T.P. , Crebelli R.
Published: March 2003

The cytokinesis‐block micronucleus (MN) assay in peripheral lymphocytes was used to assess the genetic effects of the occupational exposure to traffic fumes in policemen from the Municipality of Rome. The study population consisted of 192 subjects engaged in traffic control (exposed, 134 subjects), or in office work (controls, 58 subjects). Groups were balanced for age, gender, and smoking habits. The average benzene exposure during the workshift was 9.5 and 3.8 μg/m3 in exposed individuals and controls, respectively. All subjects were genotyped for CYP1A1, CYP2E1, GSTM1, GSTT1, and DT‐diaphorase polymorphisms. The incidence of micronuclei and micronucleated cells was recorded in 1,000 binucleated cells harvested 66 hr after mitogen stimulation. Regression analysis of data showed that MN frequency was mainly modulated by the age (P = 0.001) and gender (P = 0.001) of the study subjects (relatively higher in the elderly and females), whereas it was unaffected by the occupational exposure to traffic fumes and smoking habits. A weak (P = 0.02) association between lower MN frequency and the GSTM1 null genotype was also observed. In order to improve the sensitivity of the method to excision‐repairable lesions, a modified protocol, with exposure of cells to the repair inhibitor cytosine arabinoside (Ara‐C) during the first 16 hr of growth, was applied to 78 subjects (46 exposed and 32 controls). The results confirmed the higher MN frequency in females (P < 0.05), but failed to demonstrate any significant effect of chemical exposure (occupational or related to smoking habits). When the frequency of MN induced by Ara‐C (i.e., spontaneous values subtracted) was considered, a significant inverse correlation with age was observed (P = 0.005), possibly related to the age‐dependent decrease in repair proficiency. Environ. Mol. Mutagen. 41:126–130, 2003. © 2003 Wiley‐Liss, Inc.
Estimation of erosion and deposition volumes in a large, gravel‐bed, braided river using synoptic remote sensing
Authors: Lane Stuart N. , Westaway Richard M. , Murray Hicks D.
Published: March 2003

System‐scale detection of erosion and deposition is crucial in order to assess the transferability of findings from scaled laboratory and small field studies to larger spatial scales. Increasingly, synoptic remote sensing has the potential to provide the necessary data. In this paper, we develop a methodology for channel change detection, coupled to the use of synoptic remote sensing, for erosion and deposition estimation, and apply it to a wide, braided, gravel‐bed river. This is based upon construction of digital elevation models (DEMs) using digital photogrammetry, laser altimetry and image processing. DEMs of difference were constructed by subtracting DEM pairs, and a method for propagating error into the DEMs of difference was used under the assumption that each elevation in each surface contains error that is random, independent and Gaussian. Data were acquired for the braided Waimakariri River, South Island, New Zealand. The DEMs had a 1·0 m pixel resolution and covered an area of riverbed that is more than 1 km wide and 3·3 km long. Application of the method showed the need to use survey‐specific estimates of point precision, as project design and manufacturer estimates of precision overestimate a priori point quality. This finding aside, the analysis showed that even after propagation of error it was possible to obtain high quality DEMs of difference for process estimation, over a spatial scale that has not previously been achieved. In particular, there was no difference in the ability to detect erosion and deposition. The estimates of volumes of change, despite being downgraded as compared with traditional cross‐section survey in terms of point precision, produced more reliable erosion and deposition estimates as a result of the large improvement in spatial density that synoptic methods provide. Copyright © 2003 John Wiley & Sons, Ltd.
Convergence of steady and unsteady formulations for inviscid hovering rotor solutions
Authors: Allen C. B.
Published: March 2003

An 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

A 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

In 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

In 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

Two 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

Boron 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

Urinary 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

In 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

To 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

Is 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

Matrix 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

De 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

Novel 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

Various 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

The 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

Iacovacci 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

The 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.
Huygens' principle in the transmission line matrix method (TLM). Local theory
Authors: Enders Peter , Vanneste Christian
Published: March 2003

Huygens' principle (HP) is a well‐known fundamental principle of wave propagation. More generally, it can be understood as representing the principle of action‐by‐proximity (cf. Faraday's field theory etc.) and the superposition of secondary wavelets re‐irradiated at each point of the wavefront (Huygens' construction). These wavelets are isotropic in free space and in isotropic materials. We will show, that HP is realized within the transmission line matrix method (TLM) for scalar fields in free space of any dimension, if one considers only the scattered fields to represent the secondary wavelets. This corrects and generalizes the previous result for the total field in 2D. This property of TLM provides another explanation for its wide range of applicability. Copyright © 2003 John Wiley & Sons, Ltd.
Lithium inhibits Aβ‐induced stress in endoplasmic reticulum of rabbit hippocampus but does not prevent oxidative damage and tau phosphorylation
Authors: Ghribi Othman , Herman Mary M. , Savory John
Published: March 2003

The goal of this study was to assess the in vivo effect of Aβ on apoptosis pathways involving the endoplasmic reticulum and mitochondria, and its relationship to the induction of tau phosphorylation and DNA oxidative damage. In rabbits treated intracisternally with aggregated Aβ(1–42), clear evidence of endoplasmic reticulum stress was observed by the activation of caspase‐12 and cleavage of caspase‐3 in the endoplasmic reticulum. Mitochondrial injury was evident from the release of cytochrome c into the cytosol and the induction of oxidized mitochondrial DNA. Tau phosphorylation and nuclear translocation of NF‐κB and GSK‐3β were also observed. Treatment with lithium, an inhibitor of GSK‐3β, inhibited caspase activation but did not prevent mitochondrial DNA damage or tau hyperphosphorylation, suggesting that the translocation of GSK‐3β may represent an upstream event that leads to caspase activation but is unrelated to tau hyperphosphorylation or mitochondrial DNA oxidative damage. We propose that treatment by lithium alone is not sufficient to protect against the multiple adverse effects of Aβ, and the use of agents that prevent oxidative DNA damage and tau hyperphosphorylation, together with lithium, may provide better protection from the neurotoxic effect of Aβ. © 2003 Wiley‐Liss, Inc.
Preservation potential for Late Quaternary river alluvium
Authors: Lewin John , Macklin Mark G.
Published: March 2003

Valley sequences of Late Quaternary alluvial units reflect alluvial preservation as well as alluvial production factors. Effects of lateral channel migration, incision, aggradation and channel stability on preservation potential are explored and then considered in the light of 14 available data sets: cartographically dated and model data based on lateral channel migration; well‐mapped and dated Late Quaternary valley unit surveys; and composite age–frequency plots for dated alluvial units and flood sediments.

Despite much expectable variation between sites, and the complex effects of river‐activity combinations, a common characteristic of the data sets examined is the significance of preservation factors. Lateral migration tends to eliminate older units as it creates new alluvial deposits, whereas incision may lead to the preferential preservation of older units beyond the incision slot. Aggradational environments are likely to preserve more complete records, although simultaneous lateral migration may eliminate, possibly repeatedly, the upper parts of alluvial units. The common pattern of inset and incised streams within Pleistocene and early Holocene fills or bedrock gives finite extent to later units within narrowing valleys so that development of new valley‐floor units is necessarily at the expense of reprocessing earlier ones. Floods associated with both slack water deposits and berms are also responsible for the removal of accessible earlier materials, thus limiting the preserved record of earlier events.

In light of these censoring effects of river activities, the sequence of preserved Late Quaternary units within UK sequences is reconsidered. It is concluded that preservation potential factors have led to spatial and temporal bias in the alluvial record, and that both here and elsewhere preservation potential needs to be considered systematically alongside variable sedimentation resulting from allogenic environmental factors when interpreting the alluvial archive. Copyright © 2003 John Wiley & Sons, Ltd.
Backpackers in the Northern Territory of Australia—motives, behaviours and satisfactions
Authors: Mohsin Asad , Ryan Chris
Published: March 2003

This paper reports the findings of a study of 475 backpackers in the Northern Territory of Australia. It finds that backpackers tend to visit many of the same locations as other tourists, and like those tourists, are attracted to the natural sights of the Territory. It is also found that the backpackers can be divided into various groups. For example, of this sample about one‐third had left their previous career to travel, and about 12% had just completed studies. On the other hand about one‐quarter were holidaying during periods of normal paid holiday leave. It is argued that the market is not solely comprised of ‘life change’ or rite de passage holidaymakers. Additionally, differences are found between national groupings. Copyright © 2003 John Wiley & Sons, Ltd.
Kinetics and mechanism for the CH2O + NO2 reaction: A computational study
Authors: Xu Z. F. , Lin M. C.
Published: March 2003

The reactants, products, and transition states of the CH2O + NO2 reaction on the ground electronic potential energy surface have been searched at both B3LYP/6−311+G(d,p) and MPW1PW91/6−311+G(3df,2p) levels of theory. The forward and reverse barriers are further improved by a modified Gaussian‐2 method. The theoretical rate constants for the two most favorable reaction channels 1 and 2 producing CHO + cis‐HONO and CHO + HNO2, respectively, have been calculated over the temperature range from 200 to 3000 K using the conventional and variational transition‐state theory with quantum‐mechanical tunneling corrections. The former product channel was found to be dominant below 1500 K, above which the latter becomes competitive. The predicted total rate constants for these two product channels can be presented by kt (T) = 8.35 × 10−11 T6.68 exp(−4182/T) cm3/(mol s). The predicted values, which include the significant effect of small curvature tunneling corrections, are in quantitative agreement with the available experimental data throughout the temperature range studied (390–1650 K). © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 184–190, 2003
Preservativity logic: An analogue of interpretability logic for constructive theories
Authors: Iemhoff Rosalie
Published: March 2003

In this paper we study the modal behavior of Σ‐preservativity, an extension of provability which is equivalent to interpretability for classical superarithmetical theories. We explain the connection between the principles of this logic and some well‐known properties of HA, like the disjunction property and its admissible rules. We show that the intuitionistic modal logic given by the preservativity principles of HA known so far, is complete with respect to a certain class of frames.
DMAP/Cr(III) Catalyst Ratio: The Decisive Factor for Poly(propylene carbonate) Formation in the Coupling of CO2 and Propylene Oxide
Authors: Eberhardt Robert , Allmendinger Markus , Rieger Bernhard
Published: March 2003

Highly efficient formation of poly(propylene carbonate) can be achieved in the coupling of CO2 and propylene oxide assisted by 4‐(N,N‐dimethylamino)pyridine (DMAP) and catalyzed with salen chromium(III) chloride by using DMAP/Cr ratios of less than 2. Under these conditions a possible backbiting mechanism is suppressed, leading to only minor amounts of cyclic carbonate as a side product.

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Dual Self‐Assembling Polycondensation of p‐Acetoxybenzoic Acid and p‐Acetamidobenzoic Acid
Authors: Kimura Kunio , Kobashi Kazufumi , Maeda Hitoshi , Yamashita Yuhiko
Published: March 2003

The dual self‐assembling polycondensation of p‐acetoxybenzoic acid (ABA) and p‐acetamidobenzoic acid in Therm S 800 was examined at 300 °C. Needle‐like crystals and lath‐like crystals were formed simultaneously through reaction‐induced crystallization of oligomers at a molar ratio of 30–50 mol‐% ABA in the feed. The needle‐like crystals comprised more p‐oxybenzoyl units, whereas the lath‐like ones contained higher amounts of p‐benzamide moieties.

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Decreased striatal dopamine transporter binding in a patient with extrapontine myelinolysis
Authors: Kim Joong‐Seok , Lee Kwang‐Soo , Han Si‐Ryung , Chung Yong‐An
Published: March 2003

We describe the case of a 61‐year‐old woman who developed extrapontine myelinolysis (EPM) with parkinsonism. Decreased striatal dopamine transporter binding assessed by [123I]N‐(3‐iodopropen‐2‐yl)‐2β‐carbomethoxy‐3β‐(4‐chlorophenyl) tropane and single photon emission computed tomography ([123I]IPT) SPECT) were observed in the patient, suggesting that osmotic injury causes the demyelination of nigrostriatal dopaminergic neurons and that such injury may be involved in the pathogenesis of EPM with parkinsonism.
Burden of parkinsonism: A population‐based study
Authors: Guttman Mark , Slaughter Pamela M. , Theriault Marc‐Erick , DeBoer Donald P. , Naylor C. David
Published: March 2003

Parkinson's disease (PD) is associated with a significant burden of illness and cost to society, which has been difficult to quantify. Our objective was to use linked administrative databases from the population of Ontario, Canada, to assess the prevalence of parkinsonism, physician‐ and drug‐related costs, and hospital utilization for parkinsonian patients compared with age/sex matched controls. An inception cohort of parkinsonian cases from 1993/1994 was age and sex matched (1:2) to controls and followed for 6 years. Patients were identified by the diagnostic code for PD, the use of specific PD drugs, or a combination. The parkinsonian case cohort (15,304) was matched to (30,608) controls that did not have parkinsonism. The age‐adjusted prevalence rates were 3.63 for men and for 3.24 women per 1,000 (increased by 5.4% for men and 9.8% for women). Physician costs were 1.4 times more, there were 1.44 times more hospital admissions, admissions were on average 1.19 times longer, and drug costs were 3.0 times more for parkinsonian cases. We conclude that the substantially higher physician and drug costs as well as hospitalization rates compared with controls clearly suggest that parkinsonism is associated with large direct costs to society. © 2002 Movement Disorder Society
Pallidotomy in Parkinson's disease improves single‐joint, repetitive, ballistic movements, but fails to modify multijoint, repetitive, gestural movements
Authors: Merello Marcelo , Balej Jorge , Leiguarda Ramon
Published: March 2003

We studied 12 non‐demented PD patients in on state before and 3 months after posteroventral pallidotomy (PVP), in order to evaluate the effects of surgery upon an unconstrained, multijoint skilled movement as well as a single joint, repetitive, ballistic movement. A Selspot II System was used for three‐dimensional data acquisition, processing and reconstruction of limb trajectories. Specific wrist kinematic features of spatial accuracy (linearity and planarity), temporal attributes (acceleration and velocity), spatiotemporal relationships (velocity‐curvature coupling), and joint kinematic variables (relationships between wrist and elbow velocities and relative arm angle amplitudes) for each cycle of movement were graphically and numerically analysed. QMC was applied to single joint, repetitive, ballistic movements. QMC significantly improved after PVP (P < 0.0006). However, wrist as well as joint kinematic variables of the gestural movements failed to change significantly after PVP. The lack of improvement of the kinematic abnormalities of the gestural movement in PD patients would indicate that they are unrelated to the basic motor deficit; most likely they are the result of a disruption of a complex of sensorimotor integration processes due to abnormal parieto‐frontal basal ganglia interaction. © 2002 Movement Disorder Society
Effects of dopaminergic cell degeneration on electrophysiological characteristics and GAD65/GAD67 expression in the substantia nigra: Different action on GABA cell subpopulations
Authors: Díaz Manuel Rodríguez , Barroso‐Chinea Pedro , Acevedo Abraham , González‐Hernández Tomás
Published: March 2003

The motor disturbances occurring in Parkinson's disease have been partially attributed to a hyperactivity of γ‐aminobutyric acid (GABA) ‐ergic nigral cells largely in the substantia nigra pars reticulata (SNr) secondary to the degeneration of dopaminergic nigrostriatal neurons. However, some aspects of this response remain unclear. In this work, different electrophysiological and neurochemical parameters were studied in GABAergic cells of the SN after unilateral nigrostriatal dopaminergic lesion using 6‐hydroxydopamine injection in rats. Our data showed that 1) the SN under normal conditions contains different subsets of GABAergic cells according to their firing pattern and glutamic acid decarboxylase mRNA levels, and 2) the response of these GABAergic cell subgroups was different after the ipsi‐ and contralateral dopaminergic cell degeneration. These findings indicate a complex regulation of nigral GABAergic activity after nigrostriatal dopaminergic degeneration that probably involves local mechanisms, the nigro‐striato‐nigral loop, as well as interhemispheric mechanisms whose anatomical basis remains unstudied. © 2002 Movement Disorder Society
Reliability of reported age at onset for Parkinson's disease
Authors: Reider Carson R. , Halter Cheryl A. , Castelluccio Peter F. , Oakes David , Nichols William C. , Foroud Tatiana ,   and the Parkinson Study Group
Published: March 2003

An individual's age at onset of Parkinson disease (PD) can be collected through a variety of sources, including medical records, family report, and clinical observation. The most common source of PD age at onset information in the research setting is family‐report, which is then typically used to classify a subject as juvenile, young, or late age at onset. The reliability of the family‐reported age at onset of PD has not been rigorously examined. The present study used data from individuals diagnosed with PD to evaluate the reliability of age at onset information by comparing data obtained from three sources: 1) the subject's medical records, 2) a Family History Questionnaire, and 3) a Subject History Questionnaire. Among the 149 subjects with data for all three age at onset sources, the estimated reliability was R = 0.94. Similar reliability was observed when the sample was stratified based on gender, age at examination, disease duration, first symptom of PD, and years of education. The three measures of age at onset of PD show excellent agreement, strengthening confidence in the reliability of the reported age of clinical onset for PD. © 2002 Movement Disorder Society
An adaptive non‐conforming finite‐element method for Reissner–Mindlin plates
Authors: Carstensen Carsten , Weinberg Kerstin
Published: March 2003

Adaptive algorithms are important tools for efficient finite‐element mesh design. In this paper, an error controlled adaptive mesh‐refining algorithm is proposed for a non‐conforming low‐order finite‐element method for the Reissner–Mindlin plate model. The algorithm is controlled by a reliable and efficient residual‐based a posteriori error estimate, which is robust with respect to the plate's thickness. Numerical evidence for this and the efficiency of the new algorithm is provided in the sense that non‐optimal convergence rates are optimally improved in our numerical experiments. Copyright © 2003 John Wiley & Sons, Ltd.
Brittle fracture in polycrystalline microstructures with the extended finite element method
Authors: Sukumar N. , Srolovitz D. J. , Baker T. J. , Prévost J.‐H.
Published: March 2003

A two‐dimensional numerical model of microstructural effects in brittle fracture is presented, with an aim towards the understanding of toughening mechanisms in polycrystalline materials such as ceramics. Quasi‐static crack propagation is modelled using the extended finite element method (X‐FEM) and microstructures are simulated within the framework of the Potts model for grain growth. In the X‐FEM, a discontinuous function and the two‐dimensional asymptotic crack‐tip displacement fields are added to the finite element approximation to account for the crack using the notion of partition of unity. This enables the domain to be modelled by finite elements with no explicit meshing of the crack surfaces. Hence, crack propagation can be simulated without any user‐intervention or the need to remesh as the crack advances. The microstructural calculations are carried out on a regular lattice using a kinetic Monte Carlo algorithm for grain growth. We present a novel constrained Delaunay triangulation algorithm with grain boundary smoothing to create a finite element mesh of the microstructure. The fracture properties of the microstructure are characterized by assuming that the critical fracture energy of the grain boundary (Gcgb) is different from that of the grain interior (Gci). Numerical crack propagation simulations for varying toughness ratios Gcgb/Gci are presented, to study the transition from the intergranular to the transgranular mode of crack growth. This study has demonstrated the capability of modelling crack propagation through a material microstructure within a finite element framework, which opens‐up exciting possibilities for the fracture analysis of functionally graded material systems. Copyright © 2003 John Wiley & Sons, Ltd.
Nonprofit organization financial performance measurement: An evaluation of new and existing financial performance measures
Authors: Ritchie William J. , Kolodinsky Robert W.
Published: March 2003

Consensus about financial performance measurement remains elusive for nonprofit organization (NPO)
researchers and practitioners alike, due in part to an overall lack of empirical tests of existing and new
measures. The purpose of the current study was to explore potential similarities of financial performance measures
derived from two sources: current NPO research and key informant interviews with NPO foundation constituencies. The
authors examined financial performance measurement ratios with data from fifteen Internal Revenue Service
(IRS) Form 990 line items. Using factor analytic techniques, they found three performance factors, each
with two associated financial measurement ratios, to be present. They categorized the performance factors as
fundraising efficiency, public support, and fiscal performance. This article discusses implications of the findings
and future research.
Efffects of vigabatrin on spontaneous locomotor activity of rats
Authors: Bouwman Brigitte M. , van Rijn Clementina M. , Willems‐van Bree Elly , Coenen Anton M.L.
Published: March 2003

Effects of vigibatrin (saline, 125, 250, or 500 mg/kg i.p.) on spontaneous locomotor activity in Wistar rats were investigated. There was a dose dependent decrease in amount of locomotion for doses up to 250 mg/kg. This decrease was measurable 2–4 hours after injection and still became more pronounced in the following hours. The mean velocity during the movements 2–6 hours after injection remained intact and was higher in the 500 mg/kg group. In this high dose group an abnormal posture with a hunched back and pilo‐erection was observed. The decrease of the amount of motor activity with the preservation of the mean velocity in this non‐stimulating procedure, suggests that the level in which the experimental procedure imposes motor activity might be an important factor when measuring effects of vigabatrin. Postscript: Immediate post injection effects were observed, equivalent to those seen in the writhing test, a pain test using hyperosmolar saline injections. These observations stress the importance of controlling the osmolarity of the injection fluids.