bluuebunny/crossref_metadata_2025_split huggingface dataset:
Virtual screening to enrich hit lists from high‐throughput screening: A case study on small‐molecule inhibitors of angiogenin
Authors: Jenkins Jeremy L. , Kao Richard Y. T. , Shapiro Robert 
Published: December 2002

Abstract“Hit lists” generated by high‐throughput screening (HTS) typically contain a large percentage of false positives, making follow‐up assays necessary to distinguish active from inactive substances. Here we present a method for improving the accuracy of HTS hit lists by computationally based virtual screening (VS) of the corresponding chemical libraries and selecting hits by HTS/VS consensus. This approach was applied in a case study on the target‐enzyme angiogenin, a potent inducer of angiogenesis. In conjunction with HTS of the National Cancer Institute Diversity Set and ChemBridge DIVERSet E (∼18,000 compounds total), VS was performed with two flexible library docking/scoring methods, DockVision/Ludi and GOLD. Analysis of the results reveals that dramatic enrichment of the HTS hit rate can be achieved by selecting compounds in consensus with one or both of the VS functions. For example, HTS hits ranked in the top 2% by GOLD included 42% of the true hits, but only 8% of the false positives; this represents a sixfold enrichment over the HTS hit rate. Notably, the HTS/VS method was effective in selecting out inhibitors with midmicromolar dissociation constants typical of leads commonly obtained in primary screens. Proteins 2003;50:81–93. © 2002 Wiley‐Liss, Inc.
Prediction of load–settlement relationship for large‐diameter piles
Authors: Xiao H. B. , Luo Q. Z. , Tang J. , Li Q. S. 
Published: December 2002

AbstractAn analytical solution for the bearing capacity of a large‐diameter pile is proposed based on the load transfer function in this paper. The load–settlement relationship or the P–S curve of such a pile can be determined by the proposed method for practical application. Comparison is made between the results obtained by the proposed method and the test data, and close agreement has been found, thus verifying the accuracy of the proposed method. It is noted that the most reliable approach to the determination of the vertical load capacity of a pile is to use the ­P–S curve, which is usually obtained through on‐site load test. However, for a large‐diameter pile (e.g. a diameter over 3 m), this kind of test requires a thousand tons of test load, which sometimes is impossible to provide. It is expected that the proposed method can be used in this kind of situation. Copyright © 2002 John Wiley & Sons, Ltd.
LATTICE-GAS AUTOMATA FOR THE PROBLEM OF KINETIC THEORY OF GAS DURING FREE EXPANSION
Authors: KHOTIMAH SITI NURUL , ARIF IDAM , LIONG THE HOUW 
Published: December 2002

The lattice-gas method has been applied to solve the problem of kinetic theory of gas in the Gay–Lussac–Joule experiment. Numerical experiments for a two-dimensional gas were carried out to determine the number of molecules in one vessel (Nr), the ratio between the mean square values of the components of molecule velocity [Formula: see text], and the change in internal energy (ΔU) as a function of time during free expansion. These experiments were repeated for different sizes of an aperture in the partition between the two vessels. After puncturing the partition, the curve for the particle number in one vessel shows a damped oscillation for about half of the total number. The oscillations do not vanish after a sampling over different initial configurations. The system is in nonequilibrium due to the pressure equilibration, and here the flow is actually compressible. The equilibration time (in time steps) decreases with decreased size of aperture in the partition. For very small apertures (equal or less than [Formula: see text] lattice units), the number of molecules in one vessel changes with time in a smooth way until it reaches half of the total number; their curves obey the analytical solution for quasi-static processes. The calculations on [Formula: see text] and ΔU also support the results that the equilibration time decreases with decreased size of aperture in the partition.
Low‐modulus siloxane–polyurethanes. Part II. Effect of chain extender structure on properties and morphology
Authors: Adhikari Raju , Gunatillake Pathiraja A. , McCarthy Simon J. , Bown Mark , Meijs Gordon F. 
Published: December 2002

AbstractA series of six polyurethanes were prepared to study the effect of silicon chain extender structure on properties and morphology of siloxane–polyurethanes. Polyurethanes were prepared by a two‐step bulk polymerization without a catalyst. The soft segment of the polyurethanes was based on an 80:20 (w/w) mixture of α,ω‐bis(6‐hydroxyethoxypropyl) polydimethylsiloxane (PDMS, MW 966) and poly(hexamethylene) oxide (MW 714). The hard segment was based on 4,4′‐methylenediphenyl diisocyanate (MDI) and a 60:40 molar mixture of 1,4‐butanediol (BDO) and a silicon chain extender. Silicon chain extenders (SCE) investigated were 1,3‐bis(4‐hydroxybutyl)1,1,3,3‐tetramethyldisiloxane (BHTD), 1,3‐bis(3‐hydroxypropyl)1,1,3,3‐tetramethyldisiloxane (BPTD), 1,4‐bis(3‐hydroxypropyl)1,1,3,3‐tetramethyldisilylethylene (HTDE), 1,3‐bis(6‐hydroxyethoxypropyl)1,1,3,3‐tetramethyldisiloxane (BETD). All polyurethanes were clear and transparent with number average molecular weights between 72,000 to 116,000. Incorporation of the silicon chain extender resulted in polyurethanes with low‐modulus and high elongation. This was achieved without significant compromise in ultimate tensile strength in all cases, except BETD. Differential scanning calorimetry (DSC) results showed that the silicon chain extenders did not significantly disrupt the hard segment crystallinity, but exhibited a unique morphological feature where SCE‐based hard segments formed separate domains, which may be the primary reason for achieving low modulus without significant compromise in strength. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1092–1100, 2003
Reactive extrusion of polypropylene with supercritical carbon dioxide: Free radical grafting of maleic anhydride
Authors: Dorscht B. M. , Tzoganakis C. 
Published: December 2002

AbstractA reactive extrusion process for the functionalization of polypropylene with maleic anhydride in the presence of supercritical carbon dioxide was studied. Supercritical carbon dioxide was used in this reactive extrusion system to reduce the viscosity of the polypropylene melt phase by forming a polymer–gas solution in order to promote better mixing of the reactants. Subsequently, the effect of supercritical carbon dioxide on the level of grafting, product homogeneity, and molecular weight was evaluated. Analysis of the products revealed that the use of supercritical carbon dioxide led to improved grafting when high levels of maleic anhydride were used. The experimental results showed no evidence of an improvement in the homogeneity of the product, while melt flow rate measurements showed a reduction in the degradation of polypropylene during the grafting reaction when low levels of maleic anhydride were employed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1116–1122, 2003
Banking (on) different forms of symbolic capital
Authors: Cronin Blaise , Shaw Debora 
Published: December 2002

AbstractThe accrual of symbolic capital is an important aspect of academic life. Successful capital formation is commonly signified by the trappings of scholarly distinction or acknowledged status as a public intellectual. We consider and compare three potential indices of symbolic capital: citation counts, Web hits, and media mentions. Our findings, which are domain specific, suggest that public intellectuals are notable by their absence within the information studies community.
Complementary user‐centered methodologies for information seeking and use: System's design in the Biological Information Browsing Environment (BIBE)
Authors: Heidorn P. Bryan , Mehra Bharat , Lokhaiser Mary F. 
Published: December 2002

AbstractComplementary, socially grounded, user‐centered methodologies are being used to design new information systems to support biodiversity informatics. Each of the methods—interviews, focus groups, field observations, immersion, and lab testing—has its own strengths and weaknesses. Methods vary in their ability to reveal the automatic processes of experts (that need to be learned by novices), data richness, and their ability to help interpret complex information needs and processes. When applied in concert, the methods provide a much clearer picture of the use of information while performing a real life information‐mediated task. This picture will be used to help inform the design of a new information system, Biological Information Browsing Environment (BIBE). The groups being studied are high school students, teachers, and volunteer adult groups performing biodiversity surveys. In this task the people must identify and record information about many species of flora and fauna. Most of the information tools they use for training and during the survey are designed to facilitate the difficult species identification task.
Design of an MR‐compatible piezoelectric actuator for MR elastography
Authors: Uffmann Kai , Abicht Claus , Grote Wolfgang , Quick Harald H. , Ladd Mark E. 
Published: December 2002

AbstractMagnetic Resonance (MR) elastography is a method for measuring tissue elasticity via phase images acquired with an MR scanner. The propagation of periodic mechanical waves through the tissue can be captured by means of a modified phase contrast sequence. These waves are generated with a mechanical oscillator (actuator) and coupled into the tissue through the skin. The actuator must be capable of generating a sinusoidal excitation with excellent phase and amplitude stability, while not disturbing the MR imaging process. In this work, an actuator based on a piezoelectric principle was developed. Based on the imaging evaluation of several material samples, the housing for the piezoelectric ceramic was constructed of aluminum. Smaller parts of the housing were manufactured from brass and titanium to fulfill the mechanical constraints. A lever was used to transfer the oscillation generated by the piezoelectric ceramic to the point of excitation. The lever amplifies the piezoelectric motion, allowing for a more compact design. Three different lever designs were characterized by an acceleration sensor both outside and inside the magnet. It was shown that the rigidity of the lever, as determined by its material and form, was decisive in determining the resonant frequency of the system and therefore the maximum practical frequency of operation. It was also shown that the motion of the oscillator is unaffected by the electromagnetic fields of the MR imager. The final design can be placed directly in the magnet bore within a few centimeters of the tissue volume to be imaged without generating significant artifacts. An amplitude range of 0–1 mm in the frequency range from 0 to over 300 Hz was achieved, sufficient for performing most MR elastography applications. © 2002 Wiley Periodicals, Inc. Concepts in Magnetic Resonance (Magn Reson Engineering) 15: 239–254, 2002
Developmental and contextual influences on autonomic reactivity in young children
Authors: Alkon Abbey , Goldstein Lauren H. , Smider Nancy , Essex Marilyn J. , Kupfer David J. , Boyce W. Thomas 
Published: December 2002

AbstractStudies of cardiovascular reactivity in young children have generally employed integrated, physiologically complex measures, such as heart rate and blood pressure, which are subject to the multiple influences of factors such as blood volume, hematologic status, thermoregulation, and autonomic nervous system (ANS) tone. Reactivity studies in children have rarely employed more differentiated, proximal measures of autonomic function capable of discerning the independent effects of sympathetic and parasympathetic responses. We describe 1) the development, validity, and reliability of a psychobiology protocol assessing autonomic reactivity to challenge in 3‐ to 8‐year‐old children; 2) the influences of age, gender, and study context on autonomic measures; and 3) the distributions of reactivity measures in a normative sample of children and the prevalences of discrete autonomic profiles. Preejection period (PEP) and respiratory sinus arrythmia (RSA) were measured as indices of sympathetic and parasympathetic nervous system reactivity, respectively, and autonomic profiles were created to offer summative indices of PEP and RSA response. Results confirmed the protocol's validity and reliability, and showed differences in autonomic reactivity by age and study context, but not by gender. The studies' findings offer guidelines for future research on autonomic reactivity in middle childhood and support the feasibility of examining sympathetic and parasympathetic responses to challenge in 3‐ to 8‐year‐old children. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 64–78, 2003.
The development of “roughness” in the play fighting of rats: A Laban Movement Analysis perspective
Authors: Foroud Afra , Pellis Sergio M. 
Published: December 2002

AbstractWith increasing age, rats, when play fighting, become rougher. In part, this change can be accounted for by the increasing likelihood of using adult‐typical fighting tactics. However, even when using the same tactics, adults appear rougher than juveniles in their play. In this study, videotaped sequences of play fighting in rats from the juvenile (30 days) to the post‐pubertal (70 days) period were analyzed using Laban Movement Analysis (LMA). Movement qualities called Effort Factors in LMA captured the character of some of this change. Juveniles tended to use Indulging Efforts, whereas older rats tended to use Condensing Efforts. The latter are related to performing movements that are more controlled. This greater level of control was also evident in the way older rats maintained postural support during play fights. When standing over supine partners, juveniles are more likely to stand on the partner with all four paws, reducing their postural stability, and hence ability to control their partner's movements. Older rats are more likely to place their hind paws on the ground, thus providing a firmer anchor for movements with their upper bodies and forepaws. These age‐related changes in behavior were found for both males and females. The findings lend support to a growing body of evidence that play fighting in the juvenile phase of rats is not just a more frequently occurring version of that present in adults, but rather, has unique organizational properties. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 35–43, 2003.
Categorization of infant‐directed speech: Development from 4 to 6 months
Authors: Spence Melanie J. , Moore David S. 
Published: December 2002

AbstractTo extend a previous finding that 6‐month‐old infants categorized low‐pass filtered infant‐directed (ID) utterances, we examined a) 6‐month‐old infants' categorization of more naturalistic, unfiltered ID utterances and b) the developmental progression of ID‐speech categorization. In Experiment 1, 6‐month‐olds heard seven different unfiltered tokens from one class of ID utterance (approving or comforting), followed by a novel token from either the same or an unfamiliar category. Infants recovered, responding only to the unfamiliar category token, suggesting that they categorized naturalistic ID utterances. Four‐month‐olds' categorization of filtered and unfiltered versions of the ID utterances was assessed in Experiments 2 and 4. Four‐month‐olds did not recover, responding to a test token from an unfamiliar class, suggesting that they did not categorize either filtered or unfiltered ID utterances. Experiment 3 demonstrated that 4‐month‐old infants' failure to categorize did not result from their inability to complete the procedure. These results suggest that infants' processing of ID speech changes from 4 to 6 months of age. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 97–109, 2003.
Putting domain decomposition at the heart of a mesh‐based simulation process
Authors: Chow Peter , Addison Clifford 
Published: December 2002

AbstractIn computational mechanics analyses such as those in computational fluid dynamics and computational structure mechanics, some 60‐90% of total modelling time is taken by specifying and creating the model of the geometry and mesh. The rest of the time is spent in actual analyses and interpreting the results. This is especially true for industries such as aerospace and electronics, where 3D geometrically complex models with multiple physical processes are common. Advances in computational hardware and software have tended to increase the proportion of time spent in model creation, partly because such advances have made it feasible to solve hard and complex geometry problems in a timely fashion. This paper shows one way to exploit the advances in computation to reduce the model creation time and potentially the overall modelling time, namely the use of domain decomposition to define consistent and coherent global models based on existing component geometry and mesh models. In keeping with existing modelling processes the re‐engineering cost for the process is minimal. Copyright © 2002 John Wiley & Sons, Ltd.
Construction of interface conditions for solving the compressible Euler equations by non‐overlapping domain decomposition methods
Authors: Dolean Victorita , Nataf Frédéric , Lanteri Stéphane 
Published: December 2002

AbstractIn this work we examine the acceleration of the convergence of a non‐overlapping additive Schwarz‐type algorithm by modifying the transmission conditions applied to the subdomain interfaces. We have built generalized zero‐order interface conditions using the Smith theory of diagonalizing polynomial matrices. The numerical experiments confirmed qualitatively the behaviour in accordance with the theory, but we could not reproduce identically the results obtained in the continuous case. The preliminary results are very encouraging since they lead to a very good convergence rate for certain Mach numbers. Copyright © 2002 John Wiley & Sons, Ltd.
Current status of the molecular genetics of human prostatic adenocarcinomas
Authors: Karan Dev , Lin Ming‐Fong , Johansson Sonny L. , Batra Surinder K. 
Published: December 2002

AbstractMolecular genetic mechanisms involved in the progression of prostate cancer are not well understood due to extensive tumor heterogeneity and lack of suitable models. New methods such as fluorescence in‐situ hybridization (FISH), comparative genomic hybridization (CGH) and microsatellite analysis have documented losses or gains on various chromosomes. Altered chromosomal regions have been associated with the activation of oncogenes and the inactivation of tumor suppressor genes or defects in mismatch repair (MMR) genes. It is suggested that increased genomic instability is associated with decreased androgen‐responsive and progressive behavior of human prostate tumors, but it remains unclear whether this genomic instability is causing the progression of cancer or is the consequence of cancer. Extended studies on hereditary prostate cancer have identified 7 prostate cancer susceptibility loci on several chromosomes, but no specific gene has been confined for a large proportion of susceptibility. In this review we summarize the ongoing molecular genetic events associated with the sporadic and hereditary prostate cancer development and progression. © 2002 Wiley‐Liss, Inc.
β2‐microglobulin aberrations in diffuse large B‐cell lymphoma of the testis and the central nervous system
Authors: Jordanova Ekaterina S. , Riemersma Sietske A. , Philippo Katja , Schuuring Ed , Kluin Philip M. 
Published: December 2002

AbstractHuman leukocyte antigen (HLA) class I molecules are expressed on the surface of all nucleated cells and present antigenic peptides to cytotoxic T cells, thereby playing an important role in initiating the cellular anti‐tumor immune response. We previously reported that loss of HLA class I expression in diffuse large B‐cell lymphoma (DLBCL) of the central nervous system (CNS) and the testis is a common event. Loss of expression and mutations of the light chain of the HLA class I molecule, β2‐microglobulin (β2m) have been described in a variety of human tumors and cell lines. In our study, we screened 15 DLBCL cases with a combined loss of HLA class I and β2m expression for mutations in the latter gene by direct sequencing. Frame shift mutations in repetitive sequences within the β2m gene leading to loss of functional β2m were detected in 2 cases. Loss of heterozygosity (LOH) and fluorescent in situ hybridization (FISH) analysis for chromosome 15 exhibited loss of the remaining copy of the β2m gene in both cases but also hemizygous deletions and monosomies in 6 additional cases. Since similar mutations in the β2m gene have been associated with microsatellite instability (MSI), we used 8 markers to study MSI involvement in DLBCL. Low MSI was more frequent (33%) as compared to nodal DLBCL (n=15) but did not correlate with the β2m mutations. Our data indicate that multiple mechanisms lead to downregulation of β2m and concomitant loss of HLA class I expression in DLBCL. © 2002 Wiley‐Liss, Inc.
Effect of methylenetetrahydrofolate reductase 677C→T polymorphism on toxicity and homocysteine plasma level after chronic methotrexate treatment of ovarian cancer patients
Authors: Toffoli Giuseppe , Russo Antonio , Innocenti Federico , Corona Giuseppe , Tumolo Salvatore , Sartor Franca , Mini Enrico , Boiocchi Mauro 
Published: December 2002

AbstractMTHFR is a critical enzyme that regulates the metabolism of folate and methionine, both of which are important factors in DNA methylation and synthesis. Subjects with the 677C→T variant have impaired remethylation of Hcy to methionine that could determine hyperhomocysteinemia. Remethylation of Hcy into methionine and DNA methylation are also affected by MTX treatment. Thus, a combined effect between MTX and reduced activity of the MTHFR 677C→T polymorphism could occur, leading to toxicity. In a clinical trial, 43 ovarian cancer patients were treated with low doses of MTX. During MTX therapy, 12 patients (27.9%) developed G3/4 WHO toxicity. In these 12 patients, we observed 6 G3/4 thrombocytopenias, 1 G3 neutropenia, 1 G3 anemia, 9 G3 mucositis cases and 1 G4 mucositis case. A significant association was observed between toxicity and TT MTHFR 677 genotype (p < 0.0001). G3/4 toxicity occurred in 10 of 13 (77%), 1 of 17 (6%) and 1 of 13 (8%) patients with the TT, CT and CC MTHFR genotypes, respectively. According to the logistic regression model, patients with the TT genotype had a relative risk of 42.0 (95% CI 4.2–418.6) of developing G3/4 toxicity compared to patients with the CC and CT genotypes. Patients with the TT genotype had Hcy plasma levels after MTX therapy significantly (p = 0.0001) higher than basal levels (mean ± SD = 16.71 ± 4.72 vs. 12.48 ± 3.57 μmol/l); moreover, they also had higher Hcy plasma levels after MTX than patients with other MTHFR 677 genotypes (CC mean ± SD = 9.87 ± 3.61 μmol/l and CT mean ± SD = 11.48 ± 3.13 μmol/l). Finally, significant associations were observed between G3/4 WHO toxicity and higher Hcy plasma levels after MTX treatment (p = 0.0004). In conclusion, our data suggest that the TT MTHFR 677 genotype is associated with marked MTX‐induced hyperhomocysteinemia and could represent a pharmacogenetic marker for toxicity after chronic treatment with low doses of MTX. © 2002 Wiley‐Liss, Inc.