bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methodological development of solid‐state NMR for characterization of membrane proteins
Authors: Bjerring M. , Vosegaard T. , Malmendal A. , Nielsen N.C. 
Published: June 2003

AbstractSolid‐state NMR is a promising method for structural analysis of membrane proteins. The method is capable of providing atomic‐resolution structure information without the need for crystals or fast molecular motion as is required for X‐ray diffraction and liquid‐state NMR, respectively. However, it is clear that solid‐state NMR still needs substantial methodological development before it can provide the desired detailed information about large structures or be applied routinely for structure–function relationship studies. Here, we address some important considerations and elements in the solid‐state NMR methodology relevant for characterization of membrane proteins. These are relevant for establishing the appropriate technology and may serve as an inspiration for future developments in synthesis, isotope labeling, and physical preparation of samples for solid‐state NMR characterization. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 18A: 111–129, 2003
Type‐1 polarized nature of mouse liver CD8α– and CD8α+ dendritic cells: tissue‐dependent differences offset CD8α‐related dendritic cell heterogeneity
Authors: O'Connell Peta J. , Son Young‐Ik , Giermasz Adam , Wang Zhiliang , Logar Alison J. , Thomson Angus W. , Kalinski Pawel 
Published: June 2003

AbstractInterleukin‐12 p70 (IL‐12p70) is a major dendritic cell (DC)‐produced cytokine known to support type‐1 T helper (Th1) cells and inflammatory‐type immunity. While the ability of DC to produce bioactive IL‐12p70 depends on both the DC subtype and the microenvironmental conditions of DC development, the relative contribution of each of these factors remains unclear. Here, we report that in contrast to spleen CD8α+ and CD8α– DC that show strong differences in their respective IL‐12p70‐producing capacities, CD8α+ and CD8α– DC isolated from the liver, a non‐lymphoid organ, both efficiently produce IL‐12p70 in amounts comparable to spleen CD8α+ DC. The IL‐12p70‐producing capacity of CD8α+ and CD8α– DC from either location is greatly increased following their overnight culture in the presence of granulocyte‐macrophage colony‐stimulating factor. The elevated production of IL‐12p70 by short‐term cultured DC correlates with their enhanced expression of CD40 and other costimulatory molecules, and elevated T cell‐stimulatory capacity. These data indicate that low IL‐12‐producing capacity is not an intrinsic property of the CD8α– DC subtype, and support the hypothesis that factors such as the site of DC development and maturation stage play a dominant role in defining DC function.
Using geostatistics to elucidate temporal change in the spatial variation of aeolian sediment transport
Authors: Chappell Adrian , Mctainsh Grant , Leys John , Strong Craig 
Published: June 2003

AbstractLittle is known about the spatial and temporal scales of variation in aeolian processes. Studies that aim to investigate surface erodibility often sample aeolian sediment transport at the nodes of a regular grid of arbitrary size. Few aeolian transport investigations have the resources to obtain sufficient samples to produce reliable models for mapping the spatial variation of transport. This study reports the use of an innovative nested strategy for sampling multiple spatial scales simultaneously using 40 sediment samplers. Reliable models of the spatial variation in aeolian sediment transport were produced and used for ordinary punctual kriging and stochastic simulated annealing to produce maps for several wind erosion events over a 25 km2 playa in western Queensland, Australia. The results support the existence of a highly dynamic wind erosion system that was responding to possibly cyclic variation in the availability of material and fluctuations in wind energy. The spatial scale of transport was considerably larger than the small scale expected of the factors controlling surface erodibility. Thus, it appears that transport cannot be used as a surrogate of erodibility at the scale of this investigation. Simulation maps of transport provided considerably more information than those from kriging about the variability in aeolian sediment transport and its possible controlling factors. The proposed optimal sampling strategy involves a nested approach using ca 50 samplers. Copyright © 2003 John Wiley & Sons, Ltd.
Recent channel adjustments in alluvial rivers of Tuscany, central Italy
Authors: Rinaldi Massimo 
Published: June 2003

AbstractDrastic channel adjustments have affected the main alluvial rivers of Tuscany (central Italy) during the 20th century. Bed‐level adjustments were identified both by comparing available topographic longitudinal profiles of different years and through field observations. Changes in channel width were investigated by comparing available aerial photographs (1954 and 1993–98).Bed incision represents the dominant type of vertical adjustment, and is generalized along all the fluvial systems investigated. The Arno River system is the most affected by bed‐level lowering (up to 9 m), whereas lower incision (generally less than 2 m) is observed along the rivers of the southern part of the region. Human disturbances appear to be the dominant factors of adjustments: the main phase of vertical change occurred during the period 1945–80, in concomitance with the phase of maximum sediment mining activity at the regional scale.The second dominant type of adjustment that involved most of the rivers in the region consists of a narrowing of the active channel. Based on measurements of channel width conducted on aerial photographs, 38% of the reaches analysed experienced a narrowing greater than 50% of the initial channel width. The largest values of channel narrowing were observed along initially braided or sinuous with alternate bars morphologies in the southern portion of the region.A regional scheme of channel adjustments is derived, based on initial channel morphology and on the amounts of incision and narrowing. Different styles of channel adjustments are described. Rivers that were originally sinuous with alternate bars to braided generally became adjusted by a moderate incision and a moderate to intense narrowing; in contrast, sinuous‐meandering channels mainly adjusted vertically, with a minor amount of narrowing. Copyright © 2003 John Wiley & Sons, Ltd.
Grid transfer operators for highly variable coefficient problems in two‐level non‐overlapping domain decomposition methods
Authors: Giraud L. , Guevara Vasquez F. , Tuminaro R. S. 
Published: June 2003

AbstractWe propose a robust interpolation scheme for non‐overlapping two‐level domain decomposition methods applied to two‐dimensional elliptic problems with discontinuous coefficients. This interpolation is used to design a preconditioner closely related to the BPS scheme proposed in [Bramble et al. (Math. Comput. 1986; 47(175):103)]. Through numerical experiments, we show on structured and unstructured finite element problems that the new preconditioning scheme reduces to the BPS method on smooth problems but outperforms it on problems with discontinuous coefficients. In particular it maintains good scalable convergence behaviour even when the jumps in the coefficients are not aligned with subdomain interfaces. Copyright © 2003 John Wiley & Sons, Ltd.
Electronic properties of Si/SiGe ultrathin quantum wire superlattices
Authors: Benkhettou N. , Rached D. , Sekkal N. 
Published: June 2003

AbstractThe electronic bandstructure of ultrathin Si/Si1–xGex quantum wire superlattices is investigated using two methods. The first is the pseudopotential method of M. Jaros. The second is the first‐principles method of full potential linear muffin‐tin orbitals (FP‐LMTO) coupled to a plane‐wave basis (PLW) in the interstitial regions, which is employed to verify the results obtained with the previous method. Larger quantum wire superlattices (but always ultrathin) are also investigated. The most important result is that one of these systems is found to be promising for optoelectronic applications.
Impact of stress and long‐range interaction on ultrathin ferroelectric films
Authors: Cao Hai‐Xia , Wu Yin‐Zhong , Dong Wen , Li Zhen‐Ya 
Published: June 2003

AbstractBased on the Landau–Devonshire type theory, the polarization, critical thickness, pyroelectric coefficient and correlation length of epitaxial ultrathin ferroelectric BaTiO3 films with first‐order phase transition have been investigated using the finite difference method. The theory not only allows for the influence of the stress attributed to lattice constant misfit between the ferroelectric film and the thick substrate, but also takes into account the long‐range dipole–dipole interactions. It is shown that both the compressive stress and the long‐range interaction increase the polarization and the Curie temperature, which can be compared with the experimental results, whereas the tensile stress reduces the polarization. In addition, both the stress and long‐range interaction remarkably affect the pyroelectric coefficient and the correlation length.
Acid inhibition on the first day of dosing: comparison of four proton pump inhibitors
Authors: Pantoflickova D. , Dorta G. , Ravic M. , Jornod P. , Blum A. L. 
Published: June 2003

SummaryBackground: Rapid and consistent acid suppression on the first day of dosing may be important in treating acid‐related disorders.Aim: To compare the antisecretory activity and onset of action of single doses of rabeprazole, lansoprazole, pantoprazole, omeprazole capsule, omeprazole multiple unit pellet system (MUPS) tablet and placebo in healthy Helicobacter pylori‐negative subjects.Methods: This cross‐over, double‐blind, randomized study was performed in 18 H. pylori‐negative subjects. Twenty‐four‐hour intragastric pH monitoring was performed on the day of treatment (once‐daily dose of rabeprazole 20 mg, lansoprazole 30 mg, pantoprazole 40 mg, omeprazole capsule 20 mg, omeprazole MUPS tablet 20 mg or placebo).Results: The intragastric pH (3.4) and time at pH > 4 during the 24 h post‐dose (8.0 h) were significantly greater with rabeprazole than with lansoprazole, pantoprazole, omeprazole capsule, omeprazole MUPS tablet or placebo (P ≤ 0.04 for rabeprazole vs. the others). Daytime and night‐time pH values were higher with rabeprazole and lansoprazole than with pantoprazole, omeprazole capsule and omeprazole MUPS tablet (P ≤ 0.04).Conclusion: Rabeprazole was the most potent acid inhibitor of all the proton pump inhibitors tested during the first day of dosing.
Trans‐catheter arterial chemoembolisation for hepatocellular carcinoma in patients with viral cirrhosis: role of combined staging systems, Cancer Liver Italian Program (CLIP) and Model for End‐stage Liver Disease (MELD), in predicting outcome after treatment
Authors: Testa R. , Testa E. , Giannini E. , Botta F. , Malfatti F. , Chiarbonello B. , Fumagalli A. , Polegato S. , Podesta E. , Romagnoli P. , Risso D. , Cittadini G. , Caro G. DE 
Published: June 2003

SummaryBackground:  Trans‐catheter arterial chemoembolisation (TACE) is the most common palliative treatment for hepatocellular carcinoma (HCC). The therapeutic options depend both on the characteristics of the tumour and on functional staging of the cirrhosis.Aim:  To evaluate the effects of TACE on the survival of cirrhotic patients with HCC according to different staging systems [Okuda score, Cancer Liver Italian Program (CLIP) score, Model for End‐stage Liver Disease (MELD) score] and in relation to the side‐effects of TACE.Methods:  Fifty cirrhotic patients, 36 CTP class A and 14 class B, underwent 106 TACE treatments with mitoxantrone. Survival at 12, 24, and 36 months was evaluated.Results:  MELD at 12 months and CLIP at 24 months were identified as significant variables associated with survival. Combined cut‐offs of CLIP and of MELD identified four subgroups of patients with different survivals, at 12, 24 and 36 months, respectively: CLIP ≥ 2 and MELD ≥ 10 (63%, 20% and 0%), CLIP < 2 and MELD ≥ 10 (73%, 40% and 22%), CLIP ≥ 2 and MELD < 10 (73%, 40% and 22%) and CLIP < 2 and MELD < 10 (100%, 63% and 50%). Post‐TACE side‐effects proved to have no influence on survival.Conclusion:  In patients with poor probability of survival (CLIP ≥ 2 and MELD ≥ 10), TACE must be planned with a great deal of caution, while in patients with possibly good outcomes (CLIP < 2 and MELD < 10), more ‘aggressive’ therapy should be taken into consideration.
Teaching an engine‐driven preparation technique to undergraduates: initial observations
Authors: Hänni S. , Schönenberger K. , Peters O. A. , Barbakow F. 
Published: June 2003

AbstractAim  This paper describes the initial experiences following the introduction of a rotary engine‐driven preparation technique into the undergraduate endodontic programme at the Zurich University Dental Centre.Methods  Forty third‐year students practised the ProFile .04 (PF .04) technique between January and July 2001 in a preclinical course. Between November 2001 and February 2002, 20 of these students (Group A) root‐treated 51 teeth in their clinical course using either PF .04, the balanced force technique (BFT) or a combination of both. The second group of 20 students (Group B) similarly treated another 36 randomly selected teeth between April and July 2002. Types of teeth treated by the students and the canal preparation techniques were recorded. The students also completed a short questionnaire, evaluating their opinions of the new course.Results  Of the 87 teeth endodontically treated during the clinical course, 34, 14 and 39 were shaped using PF .04 alone, a combination of PF .04 and BFT and BFT alone, respectively. No rotary instruments were fractured during the 1‐year clinical course, although some instruments were fractured during the preclinical laboratory course. Overall, the students rated the rotary technique as positive.Conclusion  A rotary technique was successfully introduced into an undergraduate endodontic programme (this will be continued in the foreseeable future). However, the continuity between the preclinical and the clinical courses was poor as a result of the constraints of the general teaching programme.
Twelve‐week RBC storage
Authors: Hess John R. , Hill Heather R. , Oliver Cindy K. , Lippert Lloyd E. , Rugg Neeta , Joines Amy D. , Gormas Jennifer F. , Pratt P. Gayle , Silverstein Edward B. , Greenwalt Tibor J. 
Published: June 2003

BACKGROUND: Better storage can improve RBC availability and safety. Optimizing RBC ATP production and minimizing hemolysis has allowed progressively longer storage.STUDY DESIGN AND METHODS: In the first study, 24 units of packed CPD RBCs were pooled in groups of four, realiquoted, and added to 300 mL of one of four variants of experimental additive solution 76 (EAS‐76) containing 45, 40, 35, or 30 mEq per L NaCl. Units were sampled weekly for 12 weeks for morphologic and biochemical measures. In the second study, 10 volunteers donated 2 units of RBCs for a crossover comparison of Tc/Cr 24‐hour in vivo recovery of 6‐week storage in AS‐1 versus 12‐week storage in EAS‐76 variant 6 (EAS‐76v6) having 30 mEq per L NaCl.RESULTS: RBCs stored in the lower salt variants of EAS‐76 had higher concentrations of RBC ATP with less hemolysis and microvesiculation. RBC 2,3 DPG was preserved for two weeks. RBCs stored for 12 weeks in EAS‐76v6 exhibited 78 ± 4 percent 24‐hour in vivo recovery.CONCLUSIONS: It is possible to store RBCs for 12 weeks with acceptable recovery and 0.6 percent hemolysis and with normal 2,3 DPG concentrations for 2 weeks.
Detection of a healthy carrier of HCV with no evidence of antibodies for over four years
Authors: Arrojo Isidro Prat , Pareja Macarena Ortiz , Orta Maria Dolores Retamero , Luque Federico Navajas , Lamas Maria Carmen Hernandez , Gordo Hrancisco Sanchez , Mancha Isabel Vidales 
Published: June 2003

BACKGROUND: Posttransfusion HCV has been notably reduced over recent years as a result of the systematic testing for antibodies to HCV in blood donors. However, the risk of transfusing blood‐derived components from virus‐carrying donors still remains. A diagnosis is reported here of HCV in a regular blood donor who had no antibodies during the entire time she was followed up.CASE REPORT: The pharmaceutical company responsible for fractioning the plasma detected a donor who was a carrier of HCV, confirmed by PCR, but whose tests to detect anti‐HCV were systematically negative. The donor had given blood on five previous occasions, from which 14 components were manufactured. Of the 11 components traced, six had been transfused, and in the two cases in which study of the anti‐HCV was possible in the recipients, the result was positive. It was possible to check the blood samples from the donor from May 1997 to March 2002 (58 months). The tests to detect anti‐HCV were all negative, while the PCR and core antigen tests were positive.CONCLUSION: The incorporation of RNA detection or HCV core antigen techniques in blood banks may reduce the residual risk of contracting posttransfusion HCV. Measures such as the correct traceability of the components, the existence of a specimen bank, or follow up of the recipients of blood‐derived components would help to improve the quality of blood banking with percentage of survivability and case investigations.
A learning approximator for compact representation of experimental mappings
Authors: Carotenuto Riccardo 
Published: June 2003

AbstractAn iterative technique is proposed to efficiently represent n‐dimensional discrete mappings from experimental sampled data. The original sampled mapping is approximated, under some assumptions, with a proper set of one‐dimensional arrays. The proposed technique highly reduces the severe memory requirements of classical memory‐based techniques. A convergence discussion on the proposed algorithm and application examples are presented. Copyright © 2003 John Wiley & Sons, Ltd.
Preparation and adsorption properties of the chelating resins containing carboxylic, sulfonic, and imidazole groups
Authors: Rivas Bernabé L. , Jara Miguel , Pereira Eduardo D. 
Published: June 2003

AbstractThe crosslinked poly(1‐vinylimidazole‐co‐acrylic acid), P(VIm‐co‐AA), and poly(1‐vinylimidazole‐co‐2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid) P(VIm‐co‐APSA) were synthesized by radical polymerization and tested as adsorbents under competitive and noncompetitive conditions for Cu(II), Cd(II), Hg(II), Zn(II), Pb(II), and Cr(III) by batch equilibrium procedure. The resin–metal ion equilibrium was achieved before 1 h. The resin P(VIm‐co‐AA) showed a maximum retention capacity (MRC) value for Pb(II) at pH 3 and Hg(II) at pH 1 of 1.1 and 1.2 mEq/g, respectively, and the resin P(VIm‐co‐AA) showed at pH 3 the following MRC values: Hg(II) (1.5 mEq/g), Cd(II) (1.9 mEq/g), Zn(II) (2.7 mEq/g), and Cr(III) (2.8 mEq/g). The recovery of the resin was investigated at 25°C with 1 M and 4 M HNO3 and 1 M and 4 M HClO4. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2852–2856, 2003
The efficacy of complement‐mediated phagocytosis of Cryptococcus neoformans is dependent on the location of C3 in the polysaccharide capsule and involves both direct and indirectC3‐mediated interactions
Authors: Zaragoza Oscar , Taborda Carlos P. , Casadevall Arturo 
Published: June 2003

AbstractComplement component 3 (C3) is the major opsonin for the pathogenic fungus Cryptococcus neoformans in the non‐immune host. However, the efficiency of complement‐mediated opsonization varies, depending on the strain, through mechanisms that are not understood. Analysis of complement‐mediated phagocytosis for 12 strains grown in Sabouraud medium revealed that phagocytic indices were inversely correlated with capsule volume. In contrast, there was no correlation between phagocytic index and capsule volume for IgG1‐opsonized cells. When capsule size was increased, the efficacyof complement‐mediated phagocytosis decreased, whereas that of antibody‐mediated phagocytosis increased. C3 localized inside the capsule and at the outer capsule edge for poorly phagocytozed and well‐phagocytozed strains, respectively. Blocking experiments revealed that complement‐mediated phagocytosis occurred through complement receptor 3 (CR3), without significant involvement of CR1 or CR4. Blocking experiments with antibodies to C3 did not completely abrogate yeast cell uptake, consistent with phagocytosis through glucuronoxylomannan–CR3 interactions. Our data explain how some large encapsulated cells avoid phagocytosis and suggest a novel strategy for immune evasion whereby a microbial capsule interferes with phagocytosis by modifying the location of C3 deposition.
Logical inconsistencies in survey respondents' health state valuations ‐ a methodological challenge for estimating social tariffs
Authors: Devlin Nancy J. , Hansen Paul , Kind Paul , Williams Alan 
Published: June 2003

AbstractLogical inconsistencies in survey respondents' valuations of hypothetical health states – represented by the EQ‐5D, for example – present a conundrum as to whether or not their responses ought to be included for estimating social ‘tariffs’. A ‘logical inconsistency’ occurs when a state that ‘in logical terms’ is unambiguously less severe than another is assigned a lower value. Excluding such responses is defensible on data quality grounds but puts at risk the representativeness of the estimated tariff, given it is meant to represent the preferences of ‘society’. This paper explores the rationale for and effect of excluding, to varying degrees, responses distinguished by the number of pairwise inconsistencies they contain, and reports equations for two tariffs that arise from contrasting approaches. The data are from a random sample of adult New Zealanders whose visual analogue scale valuations for a selection of EQ‐5D states were collected in 1999 via a postal survey to which 1360 people responded (a 50% response rate). We conclude that there is no simple, generalisable ‘rule’ to guide exclusions and therefore researchers ought to explore the sensitivity of their estimated tariffs (and ultimately QALY estimates) to alternative treatments of logically inconsistent responses. Copyright © 2002 John Wiley & Sons, Ltd.
Demand for private health insurance: how important is the quality gap?
Authors: Costa Joan , Garcia Jaume 
Published: June 2003

AbstractPerceived quality of private and public health care, income and insurance premium are among the determinants of demand for private health insurance (PHI). In the context of a model in which individuals are expected utility maximizers, the non purchasing choice can result in consuming either public health care or private health care with full cost paid out‐of‐pocket. This paper empirically analyses the effect of the determinants of the demand for PHI on the probability of purchasing PHI by estimating a pseudo‐structural model to deal with missing data and endogeneity issues. Our findings support the hypothesis that the demand for PHI is indeed driven by the quality gap between private and public health care. As expected, PHI is a normal good and a rise in the insurance premium reduces the probability of purchasing PHI albeit displaying price elasticities smaller than one in absolute value for different groups of individuals. Copyright © 2002 John Wiley & Sons, Ltd.