bluuebunny/crossref_metadata_2025 huggingface dataset:
Amelioration of non‐alcoholic steatohepatitis and glucose intolerance in ob/ob mice by oral immune regulation towards liver‐extracted proteins is associated with elevated intrahepatic NKT lymphocytes and serum IL‐10 levels
Authors: Elinav Eran , Pappo Orit , Sklair‐Levy Miriam , Margalit Maya , Shibolet Oren , Gomori Moshe , Alper Roslana , Thalenfeld Barbara , Engelhardt Dean , Rabbani Elazar , Ilan Yaron
Published: October 2005

Non‐alcoholic steatohepatitis (NASH) is a common cause of cryptogenic cirrhosis in the Western world. In an animal model of NASH, leptin‐deficient ob/ob mice present with alterations in number and function of hepatic NKT and peripheral CD4 lymphocytes. Oral immune regulation is a method to alter the immune response towards orally administered antigens. To determine the effect of oral immune regulation towards liver‐extracted proteins on the metabolic disorders in ob/ob mice, ob/ob mice and their lean littermates were orally administered liver extracts from wild‐type or ob/ob mice or bovine serum albumin for 1 month. The effect of treatment on hepatic fat content was measured by magnetic resonance imaging (MRI) and using a histological steatohepatitis grading scale. Glucose tolerance was measured by an oral glucose tolerance test (GTT). T lymphocyte subpopulations were assessed by flow cytometry analysis. Induction of immune regulation by oral presentation of liver‐extracted proteins resulted in a significant 18% reduction of the hepatic fat content in ob/ob mice fed with either wild‐type or ob/ob liver extracts for 1 month. The MRI signal intensity index in treated mice decreased to 0.48 and 0.51, respectively, compared with 0.62 in BSA‐fed controls (p = 0.037 and p = 0.019, respectively), while the histological steatohepatitis score decreased in both treated groups to 2.0, compared with 2.4 in BSA‐fed controls (p = 0.05). A significant improvement in GTT was noted in treated ob/ob mice. These changes were accompanied by a marked increase in the intrahepatic NKT lymphocyte population in mice fed with proteins extracted from both wild‐type and ob/ob mice (46.96% and 56.72%, respectively, compared with 26.21% in BSA‐fed controls; p < 0.05) and a significant elevation in serum IL‐10 levels. Oral immune regulation towards liver extracted proteins in leptin‐deficient mice resulted in a marked reduction in hepatic fat content and improved glucose tolerance. This effect was associated with a significant increase in the intrahepatic NKT lymphocyte population and serum IL‐10 levels, suggesting a Th1 to Th2 immune shift. Immune regulation towards disease‐associated antigens holds promise as a new mode of therapy for NASH. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Rhabdomyosarcomas utilize developmental, myogenic growth factors for disease advantage: A report from the children's oncology group
Authors: Blandford Mary C. , Barr Frederic G. , Lynch James C. , Randall R.L. , Qualman Stephen J. , Keller Charles
Published: October 2005

Background

Unresectable or metastatic disease represents the greatest obstacle to cure for children with rhabdomyosarcoma. In this study we sought to identify gene expression signatures of advanced stage and progressive disease.

Procedure

Using oligonucleotide gene expression analysis for a focused set of 60 genes, we analyzed the myogenic expression profiles of 89 rhabdomyosarcomas from the Intergroup Rhabdomyosarcoma Study‐IV.

Results

While the expression profile of rhabdomyosarcomas closely paralleled gene expression profiles of normal embryonic myogenic progenitors, growth factors were most closely associated with disease progression. Specifically, we identified platelet‐derived growth factor (PDGF) receptors and insulin‐like growth factor as strongly correlated with decreased failure‐free survival. Real‐time reverse transcriptase polymerase chain reaction (RT‐PCR) of an independent data set suggested that autocrine growth signaling, if present, is not regulated in a simple manner at the transcriptional level.

Conclusions

Increased transcriptional levels of PDGF receptors and insulin‐like growth factor are associated with decreased survival in rhabdomyosarcomas. Dual blockade of these growth‐factor‐signaling pathways may be a valuable strategy in preclinical therapeutic studies. © 2005 Wiley‐Liss, Inc.
The role of Helicobacter pylori infection in children with acute immune thrombocytopenic purpura
Authors: Jaing Tang‐Her , Tsay Pei‐Kwei , Hung Iou‐Jih , Chiu Cheng‐Hsun , Yang Chao‐Ping , Huang I‐Anne
Published: October 2005

The outcome of immune thrombocytopenic purpura (ITP) is classified as acute or chronic depending on whether platelet count returns to normal. The prevalence of Helicobacter pylori infection increases with age and is independent of gender. We investigated the prevalence of H. pylori infection in Chinese children from Northern Taiwan and analyzed the association between H. pylori infection and acute ITP. Our prospective cohort studies found no statistically significant relation between H. pylori infection and acute ITP. There is therefore no indication to screen children with presumed acute ITP for H. pylori infection. © 2005 Wiley‐Liss, Inc.
Inherited predispositions and hyperactive Ras in myeloid leukemogenesis
Authors: Lauchle Jennifer O. , Braun Benjamin S. , Loh Mignon L. , Shannon Kevin
Published: October 2005

Identifying the molecular basis for inherited cancer predispositions reveals genes that when mutated, play a critical role in the earliest stages of tumorigenesis. Although rare, inherited predispositions to myeloid leukemias have led to a greater understanding of pathways important for myeloid proliferation and maturation. In particular, elucidating why children with neurofibromatosis type 1 (NF1) and Noonan syndrome (NS) are predisposed to juvenile myelomonocytic leukemia (JMML) has uncovered a critical role of hyperactive Ras signaling in normal myeloid growth and leukemogenesis. Here, we review studies of human samples and experiments performed in genetically engineered strains of mice investigating the molecular and biochemical basis of aberrant growth in JMML. These strains model human disease features and provide an opportunity to investigate novel therapeutic strategies that may ultimately cure JMML and other myeloid malignancies characterized by hyperactive Ras. © 2005 Wiley‐Liss, Inc.
Early blood transfusions protect against microalbuminuria in children with sickle cell disease
Authors: Alvarez Ofelia , Montane Brenda , Lopez Gabriela , Wilkinson James , Miller Tracie
Published: October 2005

Background

Microalbuminuria (MA) is an early indicator for glomerulopathy in sickle cell disease (SCD).

Procedure

We reviewed the medical records of asymptomatic patients ages 4–20 with sickle hemoglobinopathies, who were screened for MA in order to find out its prevalence and risk factors.

Results

Nineteen of 120 (15.8%) screened patients had MA detected by spot urine (mean albumin absolute value 6.95 ± 0.56 mg/dl) and abnormal albumin to creatinine ratios (79.8 ± 0.62 mg/g creatinine). Twenty four‐hour urine collections confirmed 57% of MA cases by spot urine. There was no difference in hyperfiltration between positive and negative patients. From the MA‐positive patients, 15 had SS (16.8% of SS group) and 4 had SC (18% of SC group). Nineteen percent of children 10 years of age or older had MA, as compared to 8% of the younger children (P = 0.018), demonstrating that increasing age is a risk factor for MA. There was a positive correlation between MA and acute chest syndrome. Young age at start of chronic transfusions was inversely related to MA and therefore renoprotective (P = 0.03). We did not see a protective effect in the group of patients taking hydroxyurea for a relatively short time, mean age at start of treatment 12 ± 5 years; however the sample was small.

Conclusions

We conclude that: (1) children with sickle cell hemoglobinopathies 10 years or older should be screened for MA and (2) chronic transfusions starting at an early age may be renoprotective. © 2005 Wiley‐Liss, Inc.
Curing childhood acute myeloid leukemia (AML) at the half‐way point: Promises to keep and miles to go before we sleep
Authors: Woods William G.
Published: October 2005

Childhood and adolescent acute myeloid leukemia (AML) is traditionally one of the hardest childhood cancers to successfully treat and had an overall survival well under 10% in the 1960s. Initial progress was made by three major events: (1) active chemotherapeutic agents were identified which led to remissions for the first time in this disease; (2) cooperative groups were instituted leading to important clinical trials; and (3) several single institutions began experimenting with the role of allogeneic matched sibling donor (MSD) BMT as effective intensification. Over the last 25 years, the cure rate has improved from <20% to 50% or higher. Most of the clinical research during this time of great advancement focused on two major themes: (1) the role of aggressive induction therapy in not only improving CR rates but in post‐remission outcomes; and (2) the role of aggressive post‐remission therapy in further improving survival, with an emphasis on high‐dose Ara C‐based chemotherapy, BMT, and supportive care. But we have “miles to go before we sleep.” Some of the challenges that will lead to ongoing reduction of population‐based mortality for AML through young adulthood include: (1) improving access of adolescents to pediatric AML therapy; (2) stratification by prognostic factors; (3) individualized therapy based on individual genetics and leukemia cell biology; (4) and the use of novel therapies including targeted immuno‐conjugates and “small molecules” which disrupt abnormal signal transduction pathways. This brief review looks at both the advances over the last three decades as well as discusses the challenges moving forward for ultimately curing all children with this disease. © 2005 Wiley‐Liss, Inc.
Response to subcutaneous therapy with mistletoe in recurrent multisystem Langerhans cell histiocytosis
Authors: Seifert Georg , Laengler Alfred , Tautz Christoph , Seeger Karl , Henze Günter
Published: October 2005

We report a case of histologically proven multisystem (MS) Langerhans cell histiocytosis (LCH) with recurrent disease reactivations after systemic chemotherapy. Through the use of subcutaneous therapy with mistletoe (MT), an inactive disease state was achieved. Pediatr Blood Cancer 2007;48:591–592. © 2005 Wiley‐Liss, Inc.
Molecular cytogenetic findings of acute leukemia included in the Brazilian Collaborative Study Group of Infant acute leukemia
Authors: Emerenciano Mariana , Agudelo Arias Diana Patricia , Coser Virginia Maria , de Brito Gilena Dantas , Macedo Silva Maria L. , Pombo‐de‐Oliveira Maria S.
Published: October 2005

Background

Chromosome abnormalities often occur prenatally in childhood leukemia, characterizing an early event in leukemogenesis. The majority of the abnormalities occurring in infants involve the MLL gene on chromosome band 11q23. We describe the molecular cytogenetic findings of 207 infant acute leukemia (IAL) cases included in the Brazilian Collaborative Study Group of Infant acute leukemia.

Procedure

The diagnosis of Acute Lymphoblastic leukemia (ALL) or acute myeloblastic leukemia (AML) was made according to morphology and immunophenotyping classification, followed by conventional karyotyping. Samples were then screened using RT‐PCR for the presence of specific chromosome translocations. FISH assay for MLL rearrangements was performed only in cases with negative or inconclusive cytogenetic or PCR results.

Results

The characteristics of children with IAL were as follows: 115 boys and 92 girls, age range 0–23 months, mean age 12 months, 145 ALL, and 62 AML. A statistically significant association was observed between pro‐B ALL cases and MLL+ve (P = 0.0001) cases and the age group 0–3 months with MLL+ve (P = 0.008) cases. Two rare cases of pro‐T ALL with MLL+ve were found. Other than MLL rearrangements, various other molecular aberrations were detected including TEL/AML1+ve (n = 9), E2A/PBX1+ve (n = 4), PML/RARA+ve (n = 4), and AML1/ETO+ve (n = 2). Cytogenetic analysis revealed hyperdiploidy (n = 6), del(7) in two cases and del(11)(q23) in seven cases.

Conclusions

Our results show that not only MLL rearrangements, but also other molecular abnormalities occur before birth and may contribute to leukemogenesis. Pediatr Blood Cancer 2006; 47:549–554. © 2005 Wiley‐Liss, Inc.
Peptide–polymer vesicles prepared by atom transfer radical polymerization
Authors: Ayres Lee , Hans P. , Adams J. , Löwik Dennis W. P. M. , van Hest Jan C. M.
Published: October 2005

The peptide Ac‐Ser‐Ala‐Gly‐Ala‐Gly‐Glu‐Gly‐Ala‐Gly‐Ala‐Gly‐Ser‐Gly‐OH was prepared with solid‐phase peptide chemistry. Before the removal of the peptide from the solid support, the alcohol side groups of the two serines were functionalized with an α‐bromo ester moiety to create a bifunctional initiator. This peptide‐based initiator was used in solution for the atom transfer radical polymerization of methyl methacrylate to yield a well‐defined ABA triblock copolymer, in which the poly(methyl methacrylate) end blocks had a number‐average molecular weight of 1.1 kg/mol (based on 1H NMR spectroscopy) and a polydispersity of 1.17. The aggregation behavior of this amphiphilic triblock copolymer was then investigated. Upon the suspension of the polymer in a mixture of tetrahydrofuran and water, followed by the removal of tetrahydrofuran, spherical aggregates were formed. By the application of different electron microscopy techniques, it was determined that these aggregates were polymersomes, presumably coexisting with large compound micelles. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6355–6366, 2005
QSAR Study of Polychlorinated Dibenzodioxins, Dibenzofurans, and Biphenyls using the Heuristic Method and Support Vector Machine
Authors: Luan F. , Ma W. P. , Zhang X. Y. , Zhang H. X. , Liu M. C. , Hu Z. D. , Fan B. T.
Published: October 2005

Quantitative structure activity relationship (QSAR) models for polychlorinated dibenzofurans (PCDFs), dibenzodioxins (PCDDs), and biphenyls (PCBs) binding to the aryl hydrocarbon receptor (AhR) have been developed based on the Heuristic Method (HM) and Support Vector Machine (SVM). Since various members of all three classes of compounds have been shown to produce qualitatively similar toxicities, a combination of the different classes for each bioactivity were performed in one QSAR study. A subset of five molecular descriptors selected by HM in CODESSA was used as inputs for SVM. The results obtained by none linear SVM model were compared with those obtained by the linear heuristic method. The prediction result of the SVM model is better than that obtained by HM. The model of SVM leads to a correlation coefficient (R) of 0.928 and mean‐square error (MSE) of 0.324 for the test set and the values for HM model are 0.845 and 0.667 respectively. This QSAR models provide a rapid, simple and valid way to model the PCDFs, PCDDs, and PCBs binding affinity in relation to the aryl hydrocarbon receptor (AhR).
Prediction of Solubility Parameters for Polymers by a QSPR Model
Authors: Yu Xinliang , Wang Xueye , Wang Hanlu , Li Xiaobing , Gao Jinwei
Published: October 2005

A set of molecular descriptors, such as hb, alk, Eint, Qii, QH and nN, which are obtained directly from polymeric repeating unit structures, are used to predict the solubility parameter (δ) of polymers and generate a quantitative structure‐property relationship (QSPR) model, with the standard error s of 0.75 (J/cc)0.5 for the training set of 51 polymers and the standard error s of 1.01 (J/cc)0.5 for the test set of 46 polymers. The calculated results show that the QSPR model is easier to apply and has better predictive capability than the existing models.
Theoretical investigation of the decomposition of acyl azides: Molecular orbital treatment
Authors: Abu‐Eittah Rafie H. , Mohamed Adel A. , Al‐Omar Ahmed M.
Published: October 2005

The thermal decomposition of formyl, acetyl, and benzoyl azides to the corresponding isocyanate and nitrogen has been treated theoretically using ab initio molecular orbital calculations at the Møller–Plesset type 2 (MP2)(full)/6‐31G* level. The reaction is stimulated by elongation of NN bond and is followed until the formation of the isocyanate and expulsion of nitrogen. The decomposition of formyl azide proved to be a concerted one‐step reaction without the formation of a nitrene intermediate. In contrast, the conversion of both acetyl and benzoyl azides to the corresponding isocyanate and nitrogen is a two‐step reaction, and a nitrene intermediate is formed. One transition state is located and identified during the course of the conversion of formyl azide, but two transition states are located and identified during the course of the conversion of acetyl and benzoyl azides. The thermodynamic functions, ΔEr and ΔHr, of the studied reactions are calculated. The results predict that the ease of conversion of the acyl azide to the isocyanate and nitrogen goes in the order: formyl azide > acetyl azide > benzoyl azide. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Symplectic partitioned Runge–Kutta scheme for Maxwell's equations
Authors: Huang Zhi‐Xiang , Wu Xian‐Liang
Published: October 2005

Using the symplectic partitioned Runge–Kutta (PRK) method, we construct a new scheme for approximating the solution to infinite dimensional nonseparable Hamiltonian systems of Maxwell's equations for the first time. The scheme is obtained by discretizing the Maxwell's equations in the time direction based on symplectic PRK method, and then evaluating the equation in the spatial direction with a suitable finite difference approximation. Several numerical examples are presented to verify the efficiency of the scheme. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Post‐translational modifications of recombinant B. cinerea EPG 6
Authors: Xie Min , Krooshof Geja H. , Benen Jacques A. E. , Atwood James. A. , King Daniel , Bergmann Carl , Orlando Ron
Published: October 2005

The fungus Botrytis cinerea is a ubiquitous plant pathogen that infects more than 200 different plant species and causes substantial economic losses in a wide range of agricultural crops and harvested products. Endopolygalacturonases (EPGs) are among the first array of cell‐wall‐degrading enzymes secreted by fungi during infection. Up to 13 EPG glycoforms have been described for B. cinerea. The presence of multiple N‐linked glycosylation modifications in BcPG1‐6 is predicted by their deduced amino acid sequences. In this work, the glycosylation sites and the attached oligosaccharide structures on BcPG6 were analyzed. The molecular mass of the intact glycoprotein was determined by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometric (MALDI‐TOFMS) analysis. BcPG6 contains seven potential N‐linked glycosylation sites. Occupancy of these glycosylation sites and the attached carbohydrate structures were analyzed by tryptic digestion followed by liquid chromatography/mass spectrometry (LC/MS) using a stepped orifice voltage approach. Five out of seven potential N‐linked sites present in BcPG6 were determined to be occupied by high‐mannose‐type oligosaccharides. Four of them were readily determined to be at Asn58 (T3 peptide), Asn198 (T7 peptide), Asn237 (T9 peptide) and Asn256 (T11 peptide), respectively. Another was located on the T8 peptide, which contained two potential N‐linked sites, Asn224 and Asn227 (SNNN224VTN227ITFK). LC/MS/MS of a sample treated with N‐glycanase placed the glycan in this peptide at Asn224 rather than at Asn227. The potential glycosylation site on Asn146 (T6 peptide) was not glycosylated. In addition, two disulfide bonds were observed, linking the Cys residues within the T13 and T16 peptides. Copyright © 2005 John Wiley & Sons, Ltd.
An overview of the BEB method for electron‐impact ionization of atoms and molecules
Authors: Stone Philip M. , Kim Yong‐Ki
Published: October 2005

An accurate and simple method for the calculation of electron‐impact ionization cross sections of atoms and molecules was developed by Kim and Rudd in 1994. Since then, many articles by Kim and coworkers have demonstrated the validity of the technique and have applied it to various atomic and molecular systems. The method is particularly useful for computational modeling, where numerous cross sections are needed. This paper presents the basic formulas and method of calculation, shows applications to some neutral atoms, and describes the NIST website where results of recent calculations are available. The limitations of the method as well as the advantages are outlined. Published in 2005 John Wiley & Sons, Ltd.
Experimental and model study of the Rh/Al system by means of EPES
Authors: Pavluch J. , Zommer L. , Polyak Y. , Pekárek Z. , Jablonski A. , Lesiak B. , Hrnčíř T. , Nehasil V.
Published: October 2005

The Rh/Al system has drawn significant attention as a model heterogeneous catalyst due to its unique adsorption properties. In this study, a set of samples consisting of Al substrates made of polished and etched pure metal sheets and deposited in situ with ultrathin Rh overlayers of different thickness was prepared. During the preparation of the samples, in‐depth diffusion of Rh into the surface region of Al substrates obviously took place. To quantify this process, i.e. by non‐destructively ascertaining the resulting depth profile of the samples, elastic peak electron spectroscopy (EPES) was employed. An EPES measurement was performed for energies of 500, 750 and 1000 eV with the initial Rh overlayer thickness in the range 3–20 Å and using pure Rh and Al standards. The measurement was carried out on a precision spherical retarding‐field analyser (RFA). The resulting experimental EPES intensities, as a function of the primary energy and the initial thickness of the Rh overlayer, were compared and fitted with the intensities simulated by the Monte Carlo (MC) method. An MC model of the sample surface consisting of three regions of different inelastic mean free path (IMFP) and Rh concentration were assumed: the first—Rh on the substrate top, the second—Rh/Al with exponential decay of Rh in Al and the third—pure Al. The best fit and best consistency for different primary energies were achieved under the assumption that no Rh was left on Al substrate top, but an exponentially decaying profile of Rh in Al was created at the surface. Copyright © 2005 John Wiley & Sons, Ltd.
Quantification of discrete oxide and sulfur layers on sulfur‐passivated InAs by XPS
Authors: Petrovykh D. Y. , Sullivan J. M. , Whitman L. J.
Published: October 2005

The initial quality and stability in air of InAs(001) surfaces passivated by a weakly‐basic solution of thioacetamide (CH3CSNH2) is examined by XPS. The S‐passivated InAs(001) surface can be modeled as a sulfur‐indium‐arsenic ‘layer‐cake’ structure, such that characterization requires quantification of both arsenic oxide and sulfur layers that are at most a few monolayers thick. This thickness range complicates the quantitative analysis because neither standard submonolayer nor thick‐film models are applicable. Therefore, we develop a discrete‐layer model and validate it with angle‐resolved XPS data and electron attenuation length (EAL) calculations. We then apply this model to empirically quantify the arsenic oxide and sulfur coverage on the basis of the corresponding XPS intensity ratios. Copyright © 2005 John Wiley & Sons, Ltd.
Monte Carlo simulation of X‐ray emission using the general‐purpose code PENELOPE
Authors: Llovet X. , Fernández‐Varea J. M. , Sempau J. , Salvat F.
Published: October 2005

PENELOPE is a general‐purpose Monte Carlo code system for the simulation of coupled electron and photon transport. It is applicable to all materials and covers the energy range from 50 eV up to 1 GeV. The code implements the most reliable cross sections and relaxation data available for the elements. Cross sections for molecules are generated by adding the atomic cross sections of the constituent atoms. The simulation of electron and positron histories is performed by using a mixed, class II, scheme; hard interactions are simulated individually, whereas the effect of soft interactions is described using multiple‐scattering approximations. The code includes a flexible geometry package for automatic tracking of particles in complex geometries consisting of homogeneous bodies limited by quadric surfaces. In this article, we describe briefly the interaction models and transport algorithms implemented in PENELOPE and present results of simulations of X‐ray generation by electron beams. Copyright © 2005 John Wiley & Sons, Ltd.
Cross sections for electron interactions in condensed matter
Authors: Fernández‐Varea J. M. , Llovet X. , Salvat F.
Published: October 2005

The fundamental components of Monte Carlo algorithms for the simulation of electron transport in matter are the differential and total cross sections for the relevant interaction mechanisms. We present different theoretical models and approximations to compute these cross sections for elastic scattering, inelastic collisions and bremsstrahlung emission of electrons with kinetic energies larger than about 100 eV. We limit our considerations to those models that are broadly applicable and suited for efficient random sampling. The approximations underlying the various models and their range of applicability are discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Monte Carlo strategies for simulations of electron backscattering from surfaces
Authors: Jablonski A. , Powell C. J. , Tanuma S.
Published: October 2005

Reliable algorithms for simulation of electron trajectories in solids are needed for quantification of Auger‐electron spectroscopy, particularly for the determination of the backscattering factor (BF). The computational schemes for this purpose should be universal, i.e. applicable to any solid for energies down to 50 eV. In addition, the algorithms should ideally require simple input parameters, e.g. the stoichiometry of the solid and the experimental configuration. Previous Monte Carlo simulations have often been based on the continuous slowing down approximation (CSDA), a relatively simple and convenient approach. However, this approach requires information on the electron stopping power for a given solid. General expressions for the stopping power are briefly reviewed and discussed. We report results of BF calculations for Cu M3VV, Ag M5VV, and Au N67VV Auger transitions from Monte Carlo simulations based on the CSDA in which stopping powers from optical data and from Tougaard's two‐parameter universal inelastic‐scattering cross section were employed. The resulting BFs, for primary energies between 500 eV and 10 keV, differed by up to 12% (at an energy of 10 keV). BFs from the Monte Carlo algorithm based on the CSDA were compared with similar results from a more sophisticated code involving simulations of individual elastic‐ and inelastic‐scattering events. Both algorithms yielded equivalent BFs for the same Auger transitions with primary energies exceeding 1000 eV; at lower energies, deviations up to 10% occurred because of an approximation in the evaluation of an integral. Copyright © 2005 John Wiley & Sons, Ltd.
Monte Carlo modeling of electron‐excited X‐ray emission from bulk materials and thin‐film/substrate systems
Authors: Nagatomi T.
Published: October 2005

A Monte Carlo (MC) simulation model for the calculation of electron‐excited X‐ray spectra was developed. The model includes characteristic K‐ and L‐lines and continuous X‐ray emission by electron impact, fluorescent X‐ray emission following absorption of continuous and characteristic X rays, L‐line X‐ray emission following K‐shell ionization and Coster‐Kronig transitions. The simulated spectra were directly compared with experimental spectra without any fitting parameters. This comparison revealed that continuous X‐ray and K‐line peak intensities can be well reproduced by the present simulation. The applications of Gryzinski's and Casnati's ionization cross sections to L‐shell ionization resulted in underestimation of the L‐line peak intensity by 10 to ∼30% and overestimation by 20 to ∼40%, respectively. Casnati's equation was found to be applicable to describing L‐shell ionization by MC modeling when the Coster‐Kronig transition was neglected. Copyright © 2005 John Wiley & Sons, Ltd.
Why is it possible to detect doped regions of semiconductors in low voltage SEM: a review and update
Authors: El‐Gomati M. , Zaggout F. , Jayacody H. , Tear S. , Wilson K.
Published: October 2005

There is an urgent need for fast, non‐destructive and quantitative two‐dimensional dopant profiling of modern and future ultra large‐scale semiconductor devices. The low voltage scanning electron microscope (LVSEM) has emerged to satisfy this need, in part, whereby it is possible to detect different secondary electron yield values (brightness in the SEM signal) from the p‐type to the n‐type doped regions as well as different brightness levels from the same dopant type. The mechanism that gives rise to such a secondary electron (SE) contrast effect is not fully understood, however. A review of the different models that have been proposed to explain this SE contrast is given. We report on new experiments that support the proposal that this contrast is due to the establishment of metal‐to‐semiconductor surface contacts. Further experiments showing the effect of instrument parameters including the electron dose, the scan speeds and the electron beam energy on the SE contrast are also reported. Preliminary results on the dependence of the SE contrast on the existence of a surface structure featuring metal‐oxide semiconductor (MOS) are also reported. Copyright © 2005 John Wiley & Sons, Ltd.
A flexible and efficient approach to E‐beam proximity effect correction—PYRAMID
Authors: Lee Soo‐Young
Published: October 2005

Electron scattering in the resist causes blurring of the written circuit features in electron‐beam (E‐beam) lithography, which is referred to as the proximity effect. As the feature size in a circuit pattern is continuously reduced in an effort to increase circuit density, the proximity effect has become too prominent to be ignored any more. Without a proper correction of the proximity effect, the pattern density and feature shapes that can be fabricated would be significantly limited especially for nanoscale circuit patterns. A hierarchical approach, named PYRAMID, was proposed in order to develop a flexible and efficient method for proximity effect correction. It distinguishes itself from other methods in that it takes a two‐level approach to exposure estimation and modification of shape and/or dose of circuit features. The hierarchical approach of PYRAMID, which exploits the shape of a typical point spread function (PSF) of the E‐beam lithographic process, attempts to reduce the computational requirement without degrading correction accuracy substantially. Through experiments and simulation, it has been demonstrated that PYRAMID has a potential to be a practical E‐beam proximity effect correction method. Currently, PYRAMID is being extended for grayscale lithography and nonrectangular features. Copyright © 2005 John Wiley & Sons, Ltd.
Modeling of imaging processes in the low‐vacuum SEM
Authors: Thiel Bradley L.
Published: October 2005

The presence of a gas in the specimen chamber of low‐vacuum scanning electron microscopes (SEMs) gives rise to a number of interactions that are not found in their high‐vacuum counterparts. Many of these interactions are integral to the specimen charge neutralizing capabilities of these instruments. However, these interactions, and the electronic charge state of the specimen, give rise to a number of processes that influence, and sometimes even dominate, secondary electron contrast. As many of the processes are stochastic in nature, and depend on discrete interactions between electrons, gaseous ions, neutral molecules, and the specimen surface, modeling can offer important insights for contrast interpretation. This paper discusses these interactions and the mechanisms through which contrast is influenced. Copyright © 2005 John Wiley & Sons, Ltd.
Monte Carlo simulation of Nb Kα secondary fluorescence in EPMA: comparison of PENELOPE simulations with experimental results
Authors: Fournelle John H. , Kim Sungtae , Perepezko John H.
Published: October 2005

Secondary fluorescence across phase boundaries is a difficult problem encountered in several electron probe microanalysis (EPMA) situations: diffusion couples; small phases enclosed in a larger phases; eutectic intergrowths; and thin films. In some cases, it is possible to construct nondiffused couples and to measure the amount of secondary fluorescence across the phase boundary, but in most cases this is difficult, time consuming, expensive, or impossible. It is thus desirable to model the secondary fluorescence by Monte Carlo methods. Here we compare the results of experimentally measured secondary fluorescence of Nb K α with results from the PENELOPE Monte Carlo program, and find that there is close correspondence. Copyright © 2005 John Wiley & Sons, Ltd.
EBSD geometry in the SEM: simulation and representation
Authors: Deal Andrew , Tao Xiaodong , Eades Alwyn
Published: October 2005

To obtain a sufficient electron backscatter diffraction (EBSD) signal in the scanning electron microscope (SEM), the sample is highly tilted. This significantly increases both the backscatter yield and the percentage of electrons that are scattered in a forward direction, making them available for detection by the phosphor screen of the EBSD camera. Unlike a conventional Everhart–Thornley detector in SE mode, which collects electrons of multiple trajectories via an applied voltage, the exact position of the phosphor screen with respect to the sample determines what solid angle of the forward scattered electrons is detected. Poor positioning of the camera or an unfavorable working distance may result in patterns that are less than ideal, increasing the difficulty of automated indexing or phase identification. Accordingly, we have used a single‐scattering Monte Carlo model to simulate electron transport through tilted samples. Results of the simulations include tracking the spatial and energy distributions of the electrons during three phases of the process: within the interaction volume, on exiting the sample surface, and when reaching the phosphor screen. Subsequent analysis fosters a better understanding of the geometric requirements for EBSD. Furthermore, our graphical representation of the Monte Carlo results is, we feel, a significant improvement over ‘connect‐the‐dots’ figures typical of the literature, providing greater insight into the nature of the backscatter yield from tilted samples. Copyright © 2005 John Wiley & Sons, Ltd.
Gelatinisation Properties of Cassava Starch in the Presence of Salts, Acids and Oxidising Agents
Authors: Jyothi Alummoottil N. , Sasikiran Korappatti , Sajeev Moothandasseri S. , Revamma R. , Moorthy Subramoney N.
Published: October 2005

The effect of various cations, anions, acids and oxidising agents on the gelatinisation properties of cassava starch was studied and wide variation was observed in the pasting and swelling properties. Sodium chloride and sodium thiosulphate slightly lowered the peak viscosity of cassava starch with increase in concentration, whereas with sodium sulphite, calcium chloride and sodium hypochlorite, a more significant decrease in the viscosity and breakdown was observed. Ferrous sulphate, alum, aluminium chloride and acids enhanced the peak viscosity at lower concentrations followed by a decrease at 1% and above. Sodium metabisulphite elevated the viscosity at 0.05 and 0.1%, while sodium hypochlorite lowered the viscosity and breakdown. DSC studies showed that aluminium chloride, sodium sulphite, and sodium thiosulphate brought about an increase in Tonset, Tend and ΔH values at higher concentrations. A decrease in swelling volume was observed from 0.05 to 1% concentration of sodium chloride and above that there was a gradual increase. With sodium sulphite, a significant increase in swelling volume was observed at 2.5 and 5% levels. With 0.05 and 0.1% aluminium chloride and sodium metabisulphite an increase in swelling volume was noticed, but at higher concentrations there was a drastic fall. Sodium chloride, sodium sulphite, sodium thiosulphate and calcium chloride brought about decrease in starch paste clarity with increase in salt concentration, whereas ferrous sulphate, aluminium chloride, sodium hypochlorite, hydrochloric acid and acetic acid improved the starch paste clarity.
On blanket statements about the epistemic effects of religious diversity
Authors: KOEHL ANDREW
Published: October 2005

Religious diversity poses a challenge to the view that exclusive religious beliefs can be justified and warranted. Equally upright and thoughtful people who appear to possess similarly well-grounded and coherent systems of belief, come up with irreconcilable religious views. The content of religious beliefs also seems unduly dependent upon culture, and no one religion has been shown to be more transformative than the others. Philosophers have recently made at least three kinds of claims about the effects of diversity on exclusive religious beliefs, and five kinds of claims about the proper effect of diversity on exclusivists themselves. Since there are numerous factors that can influence the epistemic impact of religious diversity on exclusive beliefs, each kind of blanket pronouncement made about the epistemic effects of religious diversity is inadequate.
Can faith be a doxastic venture?
Authors: BUCKAREFF ANDREI A.
Published: October 2005

In a recent article in this journal, John Bishop argues in defence of conceiving of Christian faith as a ‘doxastic venture’. That is, he defends the claim that, in exercising faith, agents believe beyond ‘what can be established rationally on the basis of evidence and argument’. Careful examination reveals that Bishop fails adequately to show that faith in the face of inadequate epistemic reasons for believing is, or can even be, a uniquely doxastic venture. I argue that faith is best conceived of as a sub-doxastic venture that involves pragmatically assuming that God exists.
A realist epistemology of faith
Authors: MACDONALD PAUL A.
Published: October 2005

In this paper, I analyse and interpret Thomas Aquinas's account of faith in order to show how Thomistic faith is a veridical cognitive state that directs the mind to God, and consequently constitutes a distinct form of knowledge of God. By assenting to the revealed propositions of faith (which express the truth about God), and thereby forming true beliefs about God under the authority and guidance of God's grace, the possessor of faith comes to know or apprehend truly something about God, even if she fails to ‘see’ or know fully the truth that she believes. A further task of the paper is to show how Thomistic faith qualifies (at least potentially) as knowledge from a contemporary epistemological standpoint, insofar as it consists of true belief that is appropriately justified and warranted, by virtue of being supernaturally informed and generated. By expositing and defending this central claim – focusing specifically on faith as a form of knowledge – I show how Aquinas offers an epistemologically realist account of faith.
Can God Be Free?: Rowe's dilemma for theology
Authors: HASKER WILLIAM
Published: October 2005

In his book, Can God Be Free?, William Rowe has argued that if God is unsurpassably good He cannot be free; if He is free, He cannot be unsurpassably good. After following the discussion of this topic through a number of historical figures, Rowe focuses on the recent and contemporary debate. A key claim of Rowe's is that, if there exists an endless series of better and better creatable worlds, then the existence of a morally perfect creator is impossible. I show that this argument is unsound, since a key premise can be proved false from propositions Rowe himself accepts.
Institutional Fragmentation and Scandinavian Childcare Variations
Authors: RAUCH DIETMAR
Published: October 2005

Institutional fragmentation is usually assumed to influence social policy outcomes in countries with constitutional features such as federalism and divided government, but not in unitary and parliamentary states. The example of childcare politics in the Scandinavian countries suggests that institutional fragmentation and veto points also can play a significant role in unitary and parliamentary systems. The rules of childcare implementation in the Scandinavian countries to a varying degree provide municipalities and NGOs with veto opportunities and veto incentives against the realization of the central government's ambition of universal childcare coverage. In Norway but not in Sweden and Denmark municipalities and NGOs have been provided with significant veto opportunities as well as considerable incentives to act. This might help to understand why Norwegian childcare development has lagged behind its Scandinavian neighbours.
Range image generator including robot motion
Authors: Gaffare Mayra Garduño , Vachon Bertrand , de los Ríos Armando Segovia
Published: October 2005

The system here described has the capability of generating range images that include robot motion. The system has two main modules, the motion and the image generator. Motion is modeled using a Bezier's curve method. To compute a range value corresponding to a pixel image, the robot position in the coordinated system is obtained from trajec-tory generation. In this way, distortion is produced in the image, or sequence of images, as a consequence of motion. The obtained range images represent scenes perceived by the robot from a specific location or during a specified dis-placement in a very “real” view.
Control and navigation aspects of a group of walking robots
Authors: Zielinska Teresa
Published: October 2005

The properties of the software part of a control system implemented in walking robots are described. The paper presents also the navigation method elaborated for a family of hexapods. The general structure of the programming system is given together with the functional description of the system modules. The event-based action scheme of the central part of the system responsible for data distribution and high level navigation is addressed in detail.
Singularity analysis of a 3-DOF parallel manipulator with R-P-S joint structure
Authors: Sokolov Alexei , Xirouchakis Paul
Published: October 2005

This paper presents a singularity analysis for a 3-DOF parallel manipulator with R-P-S (Revolute-Prismatic-Spherical) joint structure. All three types of singularities are investigated with most attention paid for direct kinematics singularities (DKS). The loci of inverse kinematics and combined singularities are identified using a new approach. The equation of DKS is defined first from the condition of existence of an instantaneous motion. The geometrical method is used to find the loci of trajectories corresponding to DKS-s. As a result of these investigations, an optimization procedure was proposed of a robot design in order to have an enlarged singularity free part of the working space. The construction of a singularity free path is discussed without changing the robot trajectory by selecting the appropriate inverse kinematics task solution.
Structure and property of the singularity loci of the 3/6-Stewart-Gough platform for general orientations
Authors: Huang Z. , Cao Y. , Li Y. W. , Chen L. H.
Published: October 2005

This paper focuses on the structure and property of the singularity loci of the 3/6-Stewart-Gough platform for general orientations. Based on the singularity kinematics principle, a planar singularity-equivalent-mechanism is proposed, by which the complicated singularity analysis of that parallel mechanism is transformed into a simpler position analysis of the planar mechanism. All the possible positions of the planar mechanism form the singularity loci of the 3/6-Stewart-Gough manipulator. The result shows that the singularity equation become quite simple moreover the structure and property of the singularity loci are also identified and explained. For the most general orientations of the typical 3/6-Stewart-Gough platform, the singularity locus equation is a special irresolvable polynomial expression of degree three, which in infinite parallel principal sections includes a parabola, four pairs of intersecting straight lines and infinity of hyperbolas. This result is beneficial to analysis of the similar issue of other Stewart-Gough manipulators.
Tactile tele-operation of a mobile robot with a collision vector
Authors: Ko Jae-Pyung , Lee Jang-Myung
Published: October 2005

In this paper, we have developed and implemented a system that combines autonomous obstacle avoidance with force-reflective tele-operation. In this system, a tele-operated mobile robot is controlled by a local two-degrees-of-freedom force-reflective joystick that a human operator holds while he is monitoring the screen. The force-reflective joystick transforms the relation between a mobile robot and the environment to the operator as a virtual force. A virtual force is generated in the form of a new collision vector and reflected to the operator, which makes the tele-operation of a mobile robot safe from collision in an uncertain and obstacle-cluttered remote environment. A mobile robot controlled by a local operator usually takes pictures of remote environments and sends the images back to the operator over the Internet. Because of limitations of communication bandwidth and the narrow view-angles of the camera, the operator cannot observe shadow regions and curved spaces. To overcome this problem, a new form of virtual force is generated along the collision vector according to both distance and approaching velocity between an obstacle and the mobile robot, which is obtained from ultrasonic sensors. This virtual force is transferred back to a master (two degrees of freedom joystick) over the Internet to enable a human operator to feel the geometrical relation between the mobile robot and the obstacle. It is demonstrated by experiments that this haptic reflection improves the performance of a tele-operated mobile robot significantly.
A FAT-based adaptive controller for robot manipulators without regressor matrix: theory and experiments
Authors: Huang An-Chyau , Wu Shi-Chang , Ting Wen-Fa
Published: October 2005

In this paper, an adaptive control scheme is proposed for an n-link rigid robot manipulator without using the regressor. The robot is firstly modeled as a set of second-order nonlinear differential equations with the assumption that all of the matrices in that model are unavailable. Since these matrices are time-varying and their variation bounds are not given, traditional adaptive or robust designs do not apply. The function approximation technique (FAT) is used here to represent uncertainties in some finite linear combinations of orthonormal basis. The dynamics of the output tracking can thus be proved to be a stable first order filter driven by function approximation errors. Using the Lyapunov stability theory, a set of update laws is derived to give closed loop stability with proper tracking performance. Experiments are also performed on a 2-D robot to test the efficacy of the proposed scheme.
Reports and Surveys
Authors: Rudall B. H.
Published: October 2005

Organic transistors have been developed to a state where, combined with pressure sensors, they may prepare the way for the development of an artificial skin that could be utilised by robots and in automation applications.
Target tracking using the efficient estimation of the image Jacobian with large residual
Authors: Kim Gon Woo , Lee Beom Hee
Published: October 2005

An efficient calibration-free visual servoing method is presented. The nonlinear optimization problem is formulated with the residual term for tracking a target. The residual term is estimated based on the secant approximation method. The image Jacobian is estimated using the affine model of the end-effector feature. Some experimental results are presented for a moving target.