bluuebunny/crossref_metadata_2025 huggingface dataset:
Perception of phrase structure in music
Authors: Knösche Thomas R. , Neuhaus Christiane , Haueisen Jens , Alter Kai , Maess Burkhard , Witte Otto W. , Friederici Angela D.
Published: January 2005

Neither music nor spoken language form uniform auditory streams, rather, they are structured into phrases. For the perception of such structures, the detection of phrase boundaries is crucial. We discovered electroencephalography (EEG) and magnetoencephalography (MEG) correlates for the perception of phrase boundaries in music. In EEG, this process was marked by a positive wave approximately between 500 and 600 ms after the offset of a phrase boundary with a centroparietal maximum. In MEG, we found major activity in an even broader time window (400–700 ms). Source localization revealed that likely candidates for the generation of the observed effects are structures in the limbic system, including anterior and posterior cingulate as well as posterior mediotemporal cortex. The timing and topography of the EEG effect bear some resemblance to a positive shift (closure positive shift, CPS) found for prosodic phrase boundaries during speech perception in an earlier study, suggesting that the underlying processes might be related. Because the brain structures, which possibly underlie the observed effects, are known to be involved in memory and attention processes, we suggest that the CPS may not reflect the detection of the phrase boundary as such, but those memory and attention related processes that are necessary to guide the attention focus from one phrase to the next, thereby closing the former and opening up the next phrase. Hum Brain Mapp 24:259–273, 2005. © 2005 Wiley‐Liss, Inc.
Salicylic acid‐derived poly(anhydride‐esters) inhibit bone resorption and formation in vivo
Authors: Harten Robert D. , Svach David J. , Schmeltzer Robert , Uhrich Kathryn E.
Published: January 2005

The objective of this study was to investigate the effects of a novel polymer that biodegrades into salicylic acid (SA) on the healing of critical sized long bone defects. Microspheres of the homopolymer, or a copolymer containing 50% less of the SA, were packed into 5‐mm mid‐diaphyseal defects in rat femurs. Control animals received collagen sponge implants. After 4 and 8 weeks of implantation, bone healing was evaluated using microradiography and quantitative histomorphometry. Four weeks postsurgery, significantly less new bone was formed in both of the polymer groups (p < 0.038). Reduced bone loss was also noted with the polymers at this time, although it was not statistically significant. However, at 8 weeks postsurgery, a statistically significant reduction in bone loss was observed in both of the polymer groups compared with controls (p < 0.0072). Both polymers seemed to elicit identical tissue responses because there were no differences detected between the homopolymer and copolymer materials at either time point. These results indicate that locally released SA can significantly reduce both bone loss and bone formation in this animal model. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res 72A: 354–362, 2005
Sensory quality and mineral and glycoalkaloid concentrations in organically and conventionally grown redskin potatoes (Solanum tuberosum)
Authors: Wszelaki Annette L , Delwiche Jeannine F , Walker Sonia D , Liggett Rachel E , Scheerens Joseph C , Kleinhenz Matthew D
Published: January 2005

Triangle tests were used to determine if panellists could distinguish (by tasting) cooked wedges of potatoes grown organically, either with (+) or without (−) compost, and conventionally. Mineral and glycoalkaloid analyses of tuber skin and flesh were also completed. When the skin remained on the potatoes, panellists detected differences between conventional potatoes and organic potatoes, regardless of soil treatment. However, they did not distinguish between organic treatments (± compost) when samples contained skin, or between any treatments if wedges were peeled prior to preparation and presentation. Glycoalkaloid levels tended to be higher in organic potatoes. In tuber skin and flesh, potassium, magnesium, phosphorus, sulfur and copper concentrations were also significantly higher in the organic treatments, while iron and manganese concentrations were higher in the skin of conventionally grown potatoes. Copyright © 2005 Society of Chemical Industry
On first order congruences of lines in ℙ4 with irreducible fundamental surface
Authors: De Poi Pietro
Published: January 2005

In this article we study congruences of lines in ℙn, and in particular of order one. After giving general results, we obtain a complete classification in the case of ℙ4 in which the fundamental surface F is in fact a variety, i.e. it is integral, and the congruence is the irreducible set of the trisecant lines of F. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A relative index on the space of 3‐dimensional embeddable CR‐structures of finite type
Authors: Greiner Peter , Staubach Wolfgang , Wang Wei
Published: January 2005

For a small deformation Φ of a 3‐dimensional pseudoconvex embeddable CR‐structure of finite type, we prove that Φ defines an embeddable CR‐structure if and only if the Szegö projection from ker $ ^{\rm \Phi} {\bar \partial} _{b} $ to ker $ {\bar \partial} _{b} $ is a Fredholm operator. This defines a relative index which is in this case equal to the negative of number of small eigenvalues of the operator $ ^{\rm \Phi} \bar \partial _{b}^{*} \, ^{\rm \Phi} \bar \partial _{b}^{} $. We also prove a cocycle formula for the relative index. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Generalized Bessel potentials on Lipschitz type spaces
Authors: Iaffei Bibiana
Published: January 2005

We introduce generalizations of Bessel potentials by considering operators of the form φ[(I – Δ)–½] where the functions φ extend the classical power case. The kernel of such an operator is subordinate to a growth function η. We explore conditions on η in such a way that these operators become isomorphisms between generalized Lipschitz spaces. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An inversion formula for the dual horocyclic Radon transform on the hyperbolic plane
Authors: Katsevich Alexander
Published: January 2005

Consider the Poincare unit disk model for the hyperbolic plane H2. Let Ξ be the set of all horocycles in H2 parametrized by (θ, p), where eiθ is the point where a horocycle ξ is tangent to the boundary |z| = 1, and p is the hyperbolic distance from ξ to the origin. In this paper we invert the dual Radon transform R* : μ(θ, p) → $ \check \mu $(z) under the assumption of exponential decay of μ and some of its derivatives. The additional assumption is that Pm(d/dp)(μm(p)ep) be even for all m ∈ ℤ. Here Pm(d/dp) is a family of differential operators introduced by Helgason, and μm(p) are the coefficients of the Fourier series expansion of μ(θ, p). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
1H and 13C assignments of three new drimenes from Iresine diffusa Humb. & Bonpl. ex Willd.
Authors: Rios María Yolanda , Berber Laura Álvarez
Published: January 2005

The structure elucidation and 1H and 13C assignments of iresin (1) and three new drimenes, 3β,14‐dihydroxy‐Δ7, 8‐drimen‐11,12‐acetonide (2), 3β,7β,14‐trihidroxy‐Δ8, 9‐drimen‐11,12‐olide (3) and 3β,7α,14‐trihydroxy‐Δ8, 9‐drimen‐11,12‐olide (4), isolated from the aerial parts of the medicinal plant Iresine diffusa Humb. & Bonpl. ex Willd. are reported. Copyright © 2005 John Wiley & Sons, Ltd.
Venous refocusing for volume estimation: VERVE functional magnetic resonance imaging
Authors: Stefanovic Bojana , Pike G. Bruce
Published: January 2005

A novel, noninvasive magnetic resonance imaging‐based method for measuring changes in venous cerebral blood volume (CBVv) is presented. Venous refocusing for volume estimation (VERVE) exploits the dependency of the spin–spin relaxation rate of deoxygenated blood on the refocusing interval. Interleaved CPMG EPI acquisitions following a train of either tightly or sparsely spaced hard refocusing pulses (every 3.7 or 30 msec, respectively) at matched echo time were used to isolate the blood signal while minimizing the intravascular blood oxygenation level dependent (BOLD) signal contribution. The technique was employed to determine the steady‐state increase in the CBVv in the visual cortex (VC) in seven healthy adult volunteers during flickering checkerboard photic stimulation. A functional activation model and a set of previously collected in vitro human whole blood relaxometry data were used to evaluate the intravascular BOLD effect on the VERVE signal. The average VC venous blood volume change was estimated to be 16 ± 2%. This method has the potential to provide efficient and continuous monitoring of venous cerebral blood volume, thereby enabling further exploration of the mechanism underlying BOLD signal changes upon physiologic, pathophysiologic, and pharmacologic perturbations. Magn Reson Med 53:339–347, 2005. © 2005 Wiley‐Liss, Inc.
Detection and correction of frequency instabilities for volumetric 1H echo‐planar spectroscopic imaging
Authors: Ebel Andreas , Maudsley Andrew A.
Published: January 2005

Spectral quality in 1H magnetic resonance spectroscopic imaging (MRSI) critically depends on the stability of the main magnetic field. For echo‐planar MRSI implemented at 3 T, temperature variation in the passive steel shims of the magnet system can lead to a significant drift in the resonance frequency. A method is presented that incorporates interleaved measurement of the instantaneous resonance frequency of a reference water signal into a volumetric MRSI sequence and allows correction for the drift during postprocessing. Results from normal human brain at 3 T indicate that the correction largely removes lineshape distortions, recovers metabolite signal loss, and improves spectral quality by reducing the width of spectral lines; however, particularly in inferior regions, other sources of distortion may be present that cause broadening of spectral lines. Magn Reson Med 53:465–469, 2005. © 2005 Wiley‐Liss, Inc.
On labeling the vertices of products of complete graphs with distance constraints
Authors: Erwin D.J. , Georges J.P. , Mauro D.W.
Published: January 2005

Variations of Hale's channel assignment problem, the L(j, k)‐labeling problem and the radio labeling problem require the assignment of integers to the vertices of a graph G subject to various distance constraints. The λj,k‐number of G and the radio number of G are respectively the minimum span among all L(j, k)‐labelings, and the minimum span plus 1 of all radio labelings of G (defined in the Introduction). In this paper, we establish the λj,k‐number of ∏ K for pairwise relatively prime integers t1 < t2 < … < tq, t1 ≥ 2. We also show the existence of an infinite class of graphs G with radio number |V(G)| for any diameter d(G). © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2005
Stability and error analysis for a spectral Galerkin method for the Navier‐Stokes equations with H2 or H1 initial data
Authors: He Yinnian
Published: January 2005

In this article we consider a spectral Galerkin method with a semi‐implicit Euler scheme for the two‐dimensional Navier‐Stokes equations with H2 or H1 initial data. The H2‐stability analysis of this spectral Galerkin method shows that for the smooth initial data the semi‐implicit Euler scheme admits a large time step. The L2‐error analysis of the spectral Galerkin method shows that for the smoother initial data the numerical solution u exhibits faster convergence on the time interval [0, 1] and retains the same convergence rate on the time interval [1, ∞). © 2005 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005.
Downregulation of internal enhancer activity contributes to abnormally low immunoglobulin expression in the MedB‐1 mediastinal B‐cell lymphoma cell line
Authors: Ritz Olga , Leithäuser Frank , Hasel Cornelia , Brüderlein Silke , Ushmorov Alexey , Möller Peter , Wirth Thomas
Published: January 2005

Primary mediastinal B‐cell lymphoma (PMBL) is a highly aggressive tumour with a unique pattern of clinical, morphological, immunological and genetic features distinct from other diffuse large B‐cell lymphomas. PMBLs are characterized by a mature B‐cell phenotype, but they typically lack immunoglobulin (Ig) gene expression. The PMBL cell line MedB‐1 shares many characteristic properties of the primary tumour, including low‐level Ig production despite a functionally rearranged IgVH gene and absence of ‘crippling’ mutations. In this study, a search was undertaken for reasons for downregulated Ig expression. Similar levels of the B‐cell‐specific transcription factors BOB.1/OBF.1 and PU.1 were found in MedB‐1 cells to those in the Ig‐producing UM‐1 lymphoblastoid cell line. However, MedB‐1 lacked the Oct2 transcription factor. Reporter assays showed that Ig‐type promoters were active in MedB‐1 cells. In contrast, activity of the intronic heavy chain enhancer was dramatically reduced. Ectopic expression of Oct2 was able partially to restore enhancer activity but transcription from the endogenous IgVH gene could not be rescued. Therefore, the role of epigenetic factors in the downregulation of Ig was investigated. Methylated histone 3 lysine 9, a reliable marker of chromatin silencing, was not detected in MedB‐1 promoter and enhancer regions. Inhibition of DNA methyltransferase and of histone deacetylases also did not reactivate Ig production. These data suggest the existence of alternative mechanisms of Ig inhibition in MedB‐1 cells, different from chromatin silencing and the lack of Oct2. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Lack of Bcl‐2 expression in follicular lymphoma may be caused by mutations in the BCL2 gene or by absence of the t(14;18) translocation
Authors: Schraders Margit , de Jong Daphne , Kluin Philip , Groenen Patricia , van Krieken Han
Published: January 2005

Follicular lymphoma (FL), except grade 3B, is characterized by the chromosomal translocation t(14;18)(q32;q21), which results in over‐expression of the Bcl‐2 protein. Ten per‐cent of all FLs, however, do not show Bcl‐2 protein expression with standard immunohistochemistry using a monoclonal Bcl‐2 antibody against residues 41–54 of the Bcl‐2 protein. In this study, the biological background of 18 Bcl‐2‐negative FL cases grade I, II, or IIIa was investigated by immunohistochemical staining and western blot analysis with alternative antibodies. Bcl‐2 protein was demonstrated in five of the 18 cases and all of these carried the t(14;18) translocation. Of the 13 cases that were Bcl‐2 negative with alternative antibodies, 12 lacked the t(14;18) translocation. PCR and subsequent sequence analysis of cDNA demonstrated that three cases with a t(14;18) contained somatic mutations in the translocated BCL2 gene, resulting in amino acid replacements in the region of the epitope recognized by the antibody. In conclusion, the majority of Bcl‐2‐negative FL lack a t(14;18) but a significant subset of these tumours are false negative due to mutations in the BCL2 gene. These findings may have consequences for the use of Bcl‐2 immunohistochemistry for diagnostic purposes. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Gene expression analysis of renal carcinoma: adipose differentiation‐related protein as a potential diagnostic and prognostic biomarker for clear‐cell renal carcinoma
Authors: Yao Masahiro , Tabuchi Hisahiro , Nagashima Yoji , Baba Masaya , Nakaigawa Noboru , Ishiguro Hitoshi , Hamada Kenji , Inayama Yoshiaki , Kishida Takeshi , Hattori Keiko , Yamada‐Okabe Hisafumi , Kubota Yoshinobu
Published: January 2005

The gene expression profiles of 33 renal cell carcinomas (RCCs) and nine normal kidney samples were examined using high‐density oligonucleotide microarrays in an attempt to identify biomolecular markers for the diagnosis of tumour subtypes and also for prediction of prognosis. Hierarchical clustering demonstrated that clear‐cell RCC, chromophobe RCC, and normal kidney tissue showed distinctive gene expression profiles. The mean expression levels of 149 of 12 500 genes were more than three times higher in clear‐cell RCC than in chromophobe RCC and normal kidney tissue. Among the genes whose expression was upregulated in clear‐cell RCC, adipose differentiation‐related protein (ADFP) and nicotinamide N‐methyltransferase (NNMT) were selected for further analysis. Consistent with the results of the microarray, increased levels of ADFP and NNMT mRNA were found more frequently in clear‐cell RCCs than in other non‐clear‐cell tumour subtypes using real‐time quantitative PCR. Immunohistochemistry for ADFP showed strong and unique tumour cell staining patterns in the majority of clear‐cell RCCs. More importantly, patients bearing tumours with higher AFDP mRNA levels showed significantly better survival in both univariate and multivariate analyses. ADFP is a lipid storage droplet‐associated protein and its transcription is considered to be regulated by the von Hippel–Lindau/hypoxia‐inducible factor pathway. It is known that clear‐cell RCC contains abundant lipids and cholesterols. Thus it is likely that sustained upregulation of ADFP following VHL inactivation is involved in the morphological appearance of clear‐cell RCC. Moreover ADFP expression status may provide useful prognostic information as a biomolecular marker in patients with clear‐cell RCC. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Identification and validation of prognostic markers in breast cancer with the complementary use of array‐CGH and tissue microarrays
Authors: Callagy Grace , Pharoah Paul , Chin Suet‐Feung , Sangan Trogon , Daigo Yataro , Jackson Lucy , Caldas Carlos
Published: January 2005

Gene amplification, an important mechanism of oncogene activation in breast cancer, can have both prognostic and therapeutic implications. In this work, an attempt is made to identify amplified genes that can be used to improve prognostication in breast cancer. A series of 52 node‐negative tumours was screened for genomic gains at 57 loci by array‐CGH. A subset of these genes was identified that could divide the series into two divergent outcome groups of either long‐term survivors or early disease‐related deaths (p = 0.01) using a combination of k‐means clustering and statistical analysis. The prognostic significance of amplification of four of the genes (EMS1, TOP2A, CCNE1, and ERBB2) was then evaluated, using fluorescent in situ hybridization on a tissue microarray, in a second larger ‘validation’ series of 232 tumours with a median follow‐up of 4.8 years. Adverse disease‐related outcome was associated with amplification of TOP2A (p = 0.004); ERBB2 (p = 0.002); and with the combined amplification of TOP2A, ERBB2, and EMS1 (p = 0.01). EMS1 amplification was more common (26% of cases) than previously reported but, in isolation, had no prognostic significance. Amplification of CCNE1, seen in only 6% of cases, had no prognostic role. These results indicate that the complementary use of array‐CGH and tissue microarrays has the potential to help in the identification and validation of molecular markers that can be used to classify breast cancers into different prognostic groups. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Differential expression of Hela‐type caldesmon in tumour neovascularization: a new marker of angiogenic endothelial cells
Authors: Zheng Ping‐Pin , van der Weiden M , Kros Johan M
Published: January 2005

Caldesmon (CaD) is a major actomyosin‐binding protein found in various cell types. There are at least two high‐molecular‐weight isoforms (h‐CaD) and four low‐molecular‐weight isoforms (l‐CaD) produced by alternative splicing. The alternatively spliced variants of the l‐CaD class are further differentiated by inclusion (Hela l‐CaD) or exclusion (WI‐38 l‐CaD) of exon 1. Currently, nothing is known about differential expression of the Hela l‐CaD in tumour neovascularization. In a previous study, expression of the Hela‐type transcripts was found in glioma blood vessels but not in the normal cerebral vasculature. To investigate whether the differentially expressed transcripts are translated into protein, a specific antibody against the peptide encoded by exon 1 was raised. Initially, exclusive expression of the protein in glioma vasculature was confirmed. To determine further whether these findings are generalizable to neovascularization in a wide variety of other tumour types, a large cohort of cancers derived from various organs, including breast, lung, kidney, colon, stomach, ovary, uterus, prostate, thyroid, liver, giving a total of 180 cases, were examined. Expression of the Hela l‐CaD was restricted to tumour vasculature and was not found in normal blood vessels. Hela l‐CaD was preferentially expressed in the early stage of tumour neovascularization and the Hela l‐CaD+ endothelial cells (ECs) were frequently enlarged, multinucleated, and developed elongated cell projections or free fragments of cytoplasm, correlating with the features of motile cells. In the Hela l‐CaD+ ECs, disassembly of focal adhesion and the formation of podosome‐like structures was observed. Therefore, the findings support the notion that quiescent ECs undergo activation of motility, necessary for ubiquitous tumour‐associated neovascularization. The data indicate that Hela l‐CaD can be considered as a marker for angiogenic ECs during the early stages of tumour neovascularization. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
CD10+ stromal cells form B‐lymphocyte maturation niches in the human bone marrow
Authors: Torlakovic Emina , Tenstad Ellen , Funderud Steinar , Rian Edith
Published: January 2005

In adult mammals, early B‐lymphopoiesis takes place in the bone marrow in close association with stromal cells. Both the phenotype of the stromal cells and the molecules involved in this essential interaction are as yet inadequately described. In this study, all benign, differentiating B‐cells (Pax‐5+ lymphoid cells) are shown, by using two‐colour immunohistochemistry on biopsies from human bone marrow, to be in close contact with scant dendritic CD10+ stromal cells until they leave via the sinusoids. This CD10+ stromal cell population does not fully overlap with the VCAM‐1+ stromal cell population. Furthermore, using a set of B‐cell differentiation markers (TdT, Pax‐5, and CD20), B‐cell development is shown to be spatially oriented, with maturation progressing towards bone marrow sinusoids. In conclusion, CD10+ stromal cells form distinct B‐lymphocyte maturation niches in the human bone marrow. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Dynamic alteration of the E‐cadherin/catenin complex during cell differentiation and invasion of undifferentiated‐type gastric carcinomas
Authors: Nakamura Etsuko , Sugihara Hiroyuki , Bamba Masamichi , Hattori Takanori
Published: January 2005

To examine qualitative alterations of the E‐cadherin/catenin complex (CCC) during cell differentiation and invasion of undifferentiated‐type gastric carcinoma, immunoreactivity for the intracytoplasmic domain and the extracellular domain (ECD) of E‐cadherin, and that of β‐catenin, was analysed in the mucosal, submucosal, and deepest invasive parts of 20 early and 20 advanced cancers that had a component of intramucosal signet ring cell carcinoma. Histological subtype affected the mode of E‐CCC alteration. The tumours with a tubular component and without organized differentiation of signet ring cells in a layered structure were associated with nuclear expression of β‐catenin and may derive from tubular adenocarcinomas through de‐differentiation and de‐regulation of the Wnt pathway. These tumours were characterized by relatively stable ECD expression throughout the course of tumour progression. On the other hand, the tumours with a layered structure, which may derive from signet ring cell carcinoma by de novo abnormality of E‐cadherin, were characterized by dynamic alteration of ECD expression during cell differentiation and tumour progression; intramucosal spread (with a layered structure) as well as deep invasion (beyond the submucosa) commonly showed cellular dissociation with downregulation of ECD, whereas submucosal invasion and lymph node metastasis often showed cellular cohesion and retention (or ‘reappearance’) of ECD. Thus, cellular dissociation did not always reflect enhanced invasive activity but may be reversibly regulated during tumour progression. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Getting the message across
Authors: Nerup Professor Jorn
Published: January 2005

This Leader is based on an interview Professor Jorn Nerup, President of the EASD, gave Practical Diabetes International during this year's meeting of the European Association for the Study of Diabetes in Jerusalem in September (see also Highlights Report on page 280).
A proteomic investigation into etoposide chemo‐resistance of neuroblastoma cell lines
Authors: Urbani Andrea , Poland Julia , Bernardini Sergio , Bellincampi Lorenza , Biroccio Antonino , Schnölzer Martina , Sinha Pranav , Federici Giorgio
Published: January 2005

Neuroblastoma, one of the most common pediatric solid tumors, originates from the peripheral sympathetic nervous system and is responsible for approximately 15% of all childhood cancer deaths. Among the several antineoplastic drugs used in neuroblastoma chemotherapeutic protocols, topoisomerase inhibitors (i.e., etoposide) represent the most commonly used. Several resistance mechanisms limit the clinical success of topoisomerase‐targeting drugs, mainly reducing the ability of neoplastic cells to start programmed cell death when exposed to antineoplastic drugs. The aim of this study was to determine, by means of proteomics, potential markers of etoposide resistance in human neuroblastoma cell lines as well as to investigate protein levels and modifications possibly involved in the onset of resistance. The etoposide resistant clone showed overexpression of the following proteins: peroxiredoxin 1, β‐galactoside soluble lectin binding protein, vimentin (three protein spots), heat shock 27 kDa protein (two protein spots) and heterogeneous nuclear ribonucleoprotein K. In addition, we also found down‐regulation of dUTP pyrophosphatase. This investigation might represent a first step towards the development of novel prognostic markers of neuroblastoma chemotherapy.
Interaction of singlet oxygen and superoxide radical anion with guanine and formation of its mutagenic modification 8‐oxoguanine
Authors: Mishra P. C. , Singh A. K. , Suhai S.
Published: January 2005

Formation of 8‐oxoguanine (8OG) from guanine in biological systems is known to cause lethal mutation and cancer. It has been suggested earlier, on the basis of experimental studies, that the oxygen molecule in its lowest singlet excited state (1O2) plays an important role in the formation of 8OG. In order to understand the possible mechanisms in this context, B3LYP/6‐31+G* and MP2/6‐31+G* calculations were carried out on the structures and stabilities of different molecules and complexes involved in the formation of 8OG. All the molecules, complexes, and transition states studied in the present report were solvated in aqueous media. Guanine has been found to make a strong complex with 1O2 with the latter species located above the imidazole ring plane, and the complex of guanine with 3O2 is much weaker than that with 1O2. Transition state calculations were carried out to study formation of 7,8‐dihydro,8‐hydroxyguanine (8OHG) and 2‐oxo‐imidazole. It has been shown that 8OG can be formed in two different ways: (i) due to interaction of the radical cation of guanine with O where 8OHG complexed with 1O2 would occur as an intermediate, and (ii) due to interaction of guanine with 1O2 leading to the formation of guanine hydroperoxide that would react with a water molecule in the presence of two 1O2 molecules serving as a source of energy to overcome the barrier. It is shown that because the interaction strengths of 3O2 and 1O2 with other molecules, e.g., guanine, are very different, a crossing of their potential energy surfaces takes place in both gas phase and aqueous media, as a result of which the lifetime of 1O2 is strongly decreased. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Density functional theory study of the hydrogen bonding interaction of 1:1 complexes of serine with water
Authors: Gong Xiaoli , Zhou Zhengyu , Du Dongmei , Dong Xiuli , Liu Shuzhen
Published: January 2005

The hydrogen bonding of 1:1 complexes formed between serine and water molecules were completely investigated in the present study employing ab initio and Density Functional Theory (DFT) methods at varied basis set levels from 6‐31g to 6‐311++g (2d,2p). For comparison, we also used the second‐order Moller–Plesset Perturbation (MP2) method at the 6‐31+g(d) level. Twelve reasonable geometries on the potential energy hypersurface of serine and water system were considered with the global minimum, 10 of which are cyclic double‐hydrogen bonded structures and the other two are one‐hydrogen bonded structures. The optimized geometric parameters and interaction energies for various isomers at different levels were estimated. The infrared spectrum frequencies, IR intensities, and the vibrational frequency shifts are reported. Finally, the solvent effects on the geometries of the serine–water complexes were also investigated using self‐consistent reaction‐field (SCRF) calculations at the B3LYP/6‐311++g(d,p) level. The results indicate that the polarity of the solvent played an important role in the structures and relative stabilities of different isomers. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Logarithmic perturbation theory for a spiked oscillator and sum rules
Authors: Bandyopadhyay S. K. , Bhattacharyya K.
Published: January 2005

We show that logarithmic perturbation theory nicely yields the wavefunction correction terms in closed forms for the spiked perturbation λ/x2 on the first excited state of the harmonic oscillator, where the conventional Rayleigh‐Schrödinger scheme is known to encounter serious problems. The study also provides a direct route to obtain several sum rules, some of which appear to be new. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Mittendrin statt nur dabei: Integration eines IT‐Risikomanagement‐Prozesses in laufende Firmenprozesse
Authors: Kleuker Stephan , Ebrahim‐Pour Roya
Published: January 2005

Risikomanagement findet in IT‐Projekten häufig nur in den Köpfen der Projektleiter statt, obwohl zugehörige Prozesse bekannt und teilweise dokumentiert sind. Der vorliegende Beitrag beschreibt eine Vorgehensweise, die zur Entwicklung und Einführung eines akzeptierten und auf die firmenindividuellen Gegebenheiten angepassten Risikomanagement‐Prozesses führt. Dabei werden grundlegende Gestaltungsaspekte für einen solchen Prozess aufbereitet.
Richtig gewichtet: Erkenntnisse aus dem Sachsen‐Rating‐Projekt
Authors: Blum Ulrich , Gleißner Werner , Leibbrand Frank
Published: January 2005

Das Projekt “Stabilisierung und Verbesserung der Beschäftigung in sächsischen mittelständischen Unternehmen – Maßnahmen vor dem Hintergrund der Baseler Beschlüsse (Basel II) und der Erfordernis einer verbesserten Risiko‐Aufstellung” (besser bekannt geworden unter “Rating in Sachsen”), zielte auf die Verringerung der Beschäftigungsprobleme Sachsens mittels eines neuen, unkonventionellen Ansatzes der Arbeitsmarktpolitik, nämlich der Stabilisierung von Unternehmen.
Faites votre jeu: Unternehmensplanung unter quantitativer Risiko‐Betrachtung
Authors: Zhou Shuqin
Published: January 2005

Wesentliche Unternehmensaktivitäten – wie etwa Personalaufbau und Kapazitätserweiterung – basieren auf der lang‐, mittel‐ oder kurzfristigen Unternehmensplanung. Daher spielen die Planungsqualität beziehungsweise ‐genauigkeit für die Erreichung der Unternehmensziele eine wichtige Rolle. Aufgrund der zunehmenden Unsicherheiten im Hinblick auf Einflussfaktoren – beispielsweise den Marktbedarf oder die Wettbewerbssituation – ist jedoch eine genaue Prognose von Unternehmenskennzahlen wie Absatz oder Umsatz nicht einfach. In dem vorliegenden Beitrag wird gezeigt, wie sich die Unsicherheiten für die Unternehmensplanung am Beispiel der Produktionskapazität quantifizieren lassen, indem die Wahrscheinlichkeitsverteilungen der Einflussparameter berücksichtigt werden. Mit Hilfe der Monte‐Carlo‐Simulation wird der Kapazitätsbedarf zu einem zukünftigen Zeitpunkt beziehungsweise sein Gesamtverlauf auf der Basis von Wahrscheinlichkeiten generiert, um die Unternehmensplanung zu erleichtern.
Junge, komm bald wieder ...
Authors: Greil Max , Komrowski Ernst Thomas , Schwarzer Joachim
Published: January 2005

Dass der Begriff “Risiko” aus der Seefahrt stammt (ital. risco = Die Klippe, die es zu umschiffen gilt), ist sicher kein Zufall. Schließlich waren unsere Vorfahren den Naturgewalten auf hoher See praktisch schutzlos ausgeliefert. Und auch heute dürfte es kaum ein Risiko geben, dem man auf den sieben Weltmeeren nicht begegnet: von Piraten über blinde Passagiere bis hin zum Risikofaktor Mensch.
Risiken der Männlichkeit
Authors: Zwick Michael M.
Published: January 2005

Die Anstrengungen der Frauenbewegung zur sozialen und wirtschaftlichen Gleichstellung der Frau haben respektable Erfolge bewirkt und das öffentliche Interesse auf das Thema “Gender” gelenkt, freilich um den Preis einer Vernachlässigung des Themas “Männlichkeit”. Erst in den letzten Jahren erfährt auch das Thema “Männlichkeit” verstärkte Zuwendung. Sich mit der sozialen Kategorie “Mann” zu beschäftigen ist nicht ohne Tücken, signalisiert doch bereits die Alltagswahrnehmung, dass es den Mann nicht gibt, sondern sich die Gattung aus einer facettenreichen Vielzahl von Protagonisten rekrutiert.
Weg mit dem Silodenken: Die Effizienz und Ertragskraft deutscher Banken im Kontext Outsourcing/Securitization/Basel II (Teil II)
Authors: Füser Karsten , Bopp Robert E.
Published: January 2005

Nachdem im ersten Teil der Serie (siehe RISKNEWS 06/2004) die Herausforderungen beschrieben wurden, denen sich die Banken aufgrund von Outsourcing gegenüber sehen, werden im Folgenden die entsprechenden Fragestellungen thematisiert, die sich durch die Verbriefung von Forderungen (Securitization) sowie die neuen Eigenkapitalrichtlinien (Basel II) ergeben. Im Anschluss wird ein Ansatz zur integrierten Behandlung des Themenkanons “Outsourcing/Securitization/Basel II” dargestellt.
Bridging the gap between statistical analysis and decision making in public health research
Authors: Stangl Dalene K.
Published: January 2005

Statisticians have eagerly taken on the role of presenting statistical summaries of quantitative data. In areas of health, this means providing point and interval estimates for quantities of interest such as diagnostic risks and treatment effects or providing curve estimates for quantities of interest such as survival probabilities across time. Methods for providing such summaries are highly formalized and constantly evolving. While decision making is the incentive for nearly all such efforts, the process that transforms statistical summaries into decisions usually remains informal and ad hoc. Statisticians have not eagerly accepted the role of promoting formalized decision‐theoretic techniques. This paper will argue that the gap between statistical synthesis and decision making is an unnatural and undesirable one, because it undermines the impact of quantitative information. An argument for bridging the gap by expanding the role of statisticians will be presented. Copyright © 2005 John Wiley & Sons, Ltd.
Statistical issues and challenges associated with rapid detection of bio‐terrorist attacks
Authors: Fienberg Stephen E. , Shmueli Galit
Published: January 2005

The traditional focus for detecting outbreaks of an epidemic or bio‐terrorist attack has been on the collection and analysis of medical and public health data. Although such data are the most direct indicators of symptoms, they tend to be collected, delivered, and analysed days, weeks, and even months after the outbreak. By the time this information reaches decision makers it is often too late to treat the infected population or to react in some other way. In this paper, we explore different sources of data, traditional and non‐traditional, that can be used for detecting a bio‐terrorist attack in a timely manner. We set our discussion in the context of state‐of‐the‐art syndromic surveillance systems and we focus on statistical issues and challenges associated with non‐traditional data sources and the timely integration of multiple data sources for detection purposes. Copyright © 2005 John Wiley & Sons, Ltd.
Modelling the incubation period of anthrax
Authors: Brookmeyer Ron , Johnson Elizabeth , Barry Sarah
Published: January 2005

Models of the incubation period of anthrax are important to public health planners because they can be used to predict the delay before outbreaks are detected, the size of an outbreak and the duration of time that persons should remain on antibiotics to prevent disease. The difficulty is that there is little direct data about the incubation period in humans. The objective of this paper is to develop and apply models for the incubation period of anthrax. Mechanistic models that account for the biology of spore clearance and germination are developed based on a competing risks formulation. The models predict that the incubation period distribution depends critically on the rate that spores are cleared from the lung and to a lesser extent on the dose of inhaled spores. The models are used in a statistical analysis of data from an anthrax outbreak that occurred in Sverdlovsk, Russia. The analysis suggests that spores are cleared from the lung at a rate between 8 per cent per day and 14 per cent per day, which is in good agreement with experimental studies of animals. The analysis suggests that at low doses, the overall median incubation period time is about 10 days, which includes a median lag of about 2 days between spore germination and onset of symptoms. Male gender and younger ages were associated with longer incubation periods as was lower dose of inhaled spores. Copyright © 2005 John Wiley & Sons, Ltd.
Ranking states' immunization coverage: an example from the National Immunization Survey
Authors: Barker Lawrence E. , Smith Philip J. , Gerzoff Robert B. , Luman Elizabeth T. , McCauley Mary M. , Strine Tara W.
Published: January 2005

The National Immunization Survey (NIS) provides state‐level estimates of preschool immunization coverage. These coverages are frequently presented in ranked lists, and ranks are frequently over‐interpreted. In this paper, we highlight the difficulty in interpreting ranked point estimates. To demonstrate the uncertainty of ranks, parametric bootstrap methods were used to derive 90 per cent confidence intervals for ranks of state vaccination coverage levels among preschool children. We graphically compared states to a reference state. If NIS data are used to rank states, one should consider presenting confidence intervals for rank and the results of comparisons of one state with another graphically. Published in 2005 by John Wiley & Sons, Ltd.
Efficient estimation of the risk of a disease by quantile‐categories of a key predictor variable using generalized additive models
Authors: Borkowf Craig B. , Albert Paul S.
Published: January 2005

Suppose that one wishes to make inference to the risk of a disease by the population quartile‐categories of a key continuous predictor variable. When one collects data on a prospective cohort, the standard method is simply to categorize the key predictor variable by the empirical quartiles. One may then include indicator variables for these empirical quartile‐categories as predictors, along with other covariates, in a generalized linear model (GLM), with the observed health status of each subject as the response. The standard GLM method, however, is relatively inefficient, because it treats all observations that fall in the same quartile‐category of the predictor variable identically, regardless of whether they lie in the centre or near the boundaries of that category. Alternatively, one may include the key predictor variable, along with other covariates, in a generalized additive model (GAM), again with the observed health status of each subject as the response. The alternative GAM method non‐parametrically estimates the functional relationship between the key predictor variable and the response. One may then compute statistics of interest, such as proportions and odds ratios, from the fitted GAM equation using the empirical quartile‐categories. Simulations show that both the GLM and GAM methods are nearly unbiased, but the latter method produces smaller variances and narrower bootstrap confidence intervals. An example from nutritional epidemiology illustrates the use of these methods. Published in 2005 by John Wiley & Sons, Ltd.
Molding and Replication of Ceramic Surfaces with Nanoscale Resolution
Authors: Auger Maria A. , Schilardi Patricia L. , Caretti Ignacio , Sánchez Olga , Benítez Guillermo , Albella José M. , Gago Raúl , Fonticelli Mariano , Vázquez Luis , Salvarezza Roberto C. , Azzaroni Omar
Published: January 2005

The design of reproducible and more efficient nanofabrication routes has become a very active research field in recent years. In particular, the development of new methods for micro‐ and nanopatterning materials surfaces has attracted the attention of many researchers in industry and academia as a consequence of the growing relevance of patterned surfaces in many technological fields, ranging from optoelectronics to biotechnology. In this work we explore, discuss, and demonstrate the possibility of extending the well‐known molding and replication strategy for patterning ceramic materials with nanoscale resolution. To achieve this goal we have combined physical deposition methods, molecule‐thick anti‐sticking coatings, and nanostructured substrates as master surfaces. This new perspective on an “old technology”, as molding is, provides an interesting alternative for high‐resolution, direct surface‐relief patterning of materials that currently requires expensive and time‐consuming lithographic approaches.
Exposure to violence and parenting as mediators between poverty and psychological symptoms in urban African American adolescents
Authors: Grant Kathryn E. , McCormick Anthony , Poindexter LaShaunda , Simpkins Tandra , Janda Cassandra M. , Thomas Kina J. , Campbell Amanda , Carleton Russell , Taylor Jeremy
Published: January 2005

The present study builds on past research that has found support for a conceptual model in which poverty is linked with adolescent psychological symptoms through economic stressors and impaired parenting. The present study examined this model in a sample of urban African American mothers and their adolescent children. In addition, an alternative hypothesis was examined: that exposure to community violence mediates the relation between poverty and psychological symptoms in urban youth. Limited support was found for a model in which poverty is linked with internalizing symptoms through exposure to community violence and with externalizing symptoms through economic stressors and inconsistent discipline. Interpretations, limitations, and directions for future research are outlined.
On a Cahn–Hilliard model for phase separation with elastic misfit
Authors: Garcke Harald
Published: January 2005

Existence of solutions to a Cahn–Hilliard system taking elastic stresses into account is shown. The analysis is hindered by a logarithmic singularity and a quadratic term in the displacement gradient. This makes careful a priori estimates for both terms necessary. In particular, a global version of

L^{p}

-estimates for gradients of nonlinear elliptic systems is shown in order to control the logarithmic singularity.

On établit l'existence de solutions pour un système de Cahn–Hilliard qui tient compte des stress élastiques. Cette analyse est rendue plus difficile à cause d'une singularité logarithmique et d'un terme quadratique dans le gradient déplacé, qu'on va devoir a priori estimer. En particulier, pour contrôler la singularité logarithmique on démontre une version globale des

L^{p}

-estimatiens pour les gradients des systèmes elliptiques nonlinénaires.
Inhomogeneous mechanical behavior of the human supraspinatus tendon under uniaxial loading
Authors: Huang Chun‐Yuh , Wang Vincent M. , Pawluk Robert J. , Bucchieri John S. , Levine William N. , Bigliani Louis U. , Mow Van C. , Flatow Evan L.
Published: January 2005

Disorders of the rotator cuff, particularly tears of the rotator cuff tendons, cause significant shoulder disability. Among numerous factors thought to be responsible for the initiation and progression of supraspinatus tears are those related to the tendon's biomechanical properties. We hypothesized that in supraspinatus tendons subjected to tensile loading a strain gradient (difference) exists between the articular and bursal tendon surfaces, that regional strain differences exist on each of these two tendon surfaces, and that tendon surface strains vary with glenohumeral abduction. To test these hypotheses, the intrinsic inhomogeneous deformational characteristics of the articular and bursal surfaces of eight intact human cadaveric supraspinatus tendons were studied at three glenohumeral abduction angles using a novel multiple strain measuring system which simultaneously recorded surface marker displacements on two opposing soft tissue surfaces. Under applied tensile loads, the articular surface exhibited greater strain at 22° (7.4 ± 2.6% vs. 1.3 ± 0.7%, p = 0.0002) and 63° (6.4 ± 1.6% vs. 2.7 ± 1.2%, p = 0.0001) whereas the bursal surface exhibited greater strain at 90° (7.6 ± 2.8% vs. 4.9 ± 0.4%, p = 0.013). At all abduction angles, insertion strains were higher than those of the mid‐tendon and tendon–muscle junction regions. The existence of inhomogeneous surface strains in the intact supraspinatus tendon demonstrates that intratendinous shear occurs within the tendon. The higher strain on the articular side of the tendon, especially at the insertion region, suggests a propensity for tears to initiate in the articular tendinous zone. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
McTaggart's Argument
Authors: Corish Denis
Published: January 2005

The argument of J. M. E. McTaggart in ‘The Unreality of Time’ (Mind 1908) fails logically. There is no A series as such, but there is a shifting past-present-future arrangement within and consistent with the earlier-later B series, past being always earlier, future always later, present always a position earlier or later. An exactly similar logical structure is constructible within the number series, by making each number as one goes up it in turn (it does not matter what ‘it’, or ‘present’, means, ontologically). The subsequent argument that past-present-future time falls into contradiction then fails also, and proves to be equivocal.
Truth and the Magic of ‘Is’
Authors: MacKenzie P. T.
Published: January 2005

Both the Correspondence Theory of Truth and the Redundancy/Performative Theory of Truth appear to be unquestionably correct and yet each seems to be inconsistent with the other. As a result we have a puzzle.

The way out of this dilemma is to be found by taking a closer look at the role that ‘Is’ and its cognates play in the structure of the standard statement. Once this is done it can be seen that both theories are compatible with one another.
Dummett on the Time-Continuum
Authors: Meyer Ulrich
Published: January 2005

Michael Dummett claims that the classical model of time as a continuum of instants has to be rejected. In his view, “it allows as possibilities what reason rules out, and leaves it to the contingent laws of physics to rule out what a good model of physical reality would not even be able to describe.” This paper argues otherwise.