bluuebunny/crossref_metadata_2025_split huggingface dataset:
Significant glass‐transition‐temperature increase through hydrogen‐bonded copolymers
Authors: Kuo Shiao‐Wei , Xu Hongyao , Huang Chih‐Feng , Chang Feng‐Chih 
Published: September 2002

AbstractThe role of hydrogen bonding in promoting intermolecular cohesion and higher glass‐transition temperatures of polymer is a subject of longstanding interest. A series of poly(vinylphenol‐co‐vinylpyrrolidone) copolymers were prepared by the free‐radical copolymerization of acetoxystyrene and vinylpyrrolidone; this was followed by the selective removal of the acetyl protective group, with corresponding and significant glass‐transition‐temperature increases after this procedure. The incorporation of acetoxystyrene into poly(vinylpyrrolidone) resulted in lower glass‐transition temperatures because of the reduced dipole interactions in its homopolymers. However, the deacetylation of acetoxystyrene to transform the poly(vinylphenol‐co‐vinylpyrrolidone) copolymer enhanced the higher glass‐transition temperature because of the strong hydrogen bonding in the copolymer chain. The thermal properties and hydrogen bonding of these two copolymers were investigated with differential scanning calorimetry and Fourier transform infrared spectroscopy, and good correlations between the thermal behaviors and IR results were observed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2313–2323, 2002
Learning as discourse change: A sociocultural mechanism
Authors: Wickman Per‐Olof , Östman Leif 
Published: September 2002

AbstractThis paper deals with a theoretical mechanism for learning and a methodological approach for analyzing meaning making in classroom talk and action. It examines the potential of the approach for illuminating learning on a discursive level, i.e., how discourses change and how individuals become participants of new practices. Our approach involves a high‐resolution analysis of how meaningful relations are built in encounters between individuals and between individuals and the world. The approach is based mainly on the work of the later Wittgenstein, but also on pragmatism and sociocultural research. To demonstrate how our approach can be used, we analyze what university students learn during a practical on insects. We specifically demonstrate how the encounters with physical pinned insects contribute to the meaning students make and how these encounters interact with other experiences during laboratory work. © 2002 Wiley Periodicals, Inc. Sci Ed 86:601–623, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/sce.10036
Towards renewed research questions from the outcomes of the European project Labwork in Science Education
Authors: Séré Marie‐Geneviève 
Published: September 2002

AbstractA research project about labwork at Upper secondary and Undergraduate levels was launched in 1996, funded by the European Commission. Seven research groups from six European countries participated in the surveys at European scale and carried out a number of case‐studies. This common work allowed numerous discussions which, months later, permit to articulate renewed directions of research about labwork. In this paper, new research questions are presented, drawing upon the outcomes of the project. One of them was to disclose numerous potential objectives which can be aimed for in a laboratory. This means that conscious choices must be taken among objectives. These are studied in this paper under the three classical headings of conceptual/epistemological/procedural objectives. © 2002 Wiley Periodicals, Inc. Sci Ed 86:624–644, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/sce.10040
Scientists as writers
Authors: Yore Larry D. , Hand Brian M. , Prain Vaughan 
Published: September 2002

AbstractThis study attempted to establish an image of a science writer based on a synthesis of writing theory, models, and research literature on academic writing in science and other disciplines and to contrast this image with an actual prototypical image of scientists as writers of science. The synthesis was used to develop a questionnaire to assess scientists' writing habits, beliefs, strategies, and perceptions about print‐based language. The questionnaire was administered to 17 scientists from science and applied science departments of a large Midwestern land grant university. Each respondent was interviewed following the completion of the questionnaire with a custom‐designed semistructured protocol to elaborate, probe, and extend their written responses. These data were analyzed in a stepwise fashion using the questionnaire responses to establish tentative assertions about the three major foci (type of writing done, criteria of good science writing, writing strategies used) and the interview responses to verify these assertions. Two illustrative cases (a very experienced, male physical scientist and a less experienced, female applied biological scientist) were used to highlight diversity in the sample. Generally, these 17 scientists are driven by the academy's priority of publishing their research results in refereed, peer‐reviewed journals. They write their research reports in isolation or as a member of a large research team, target their writing to a few journals that they also read regularly, use writing in their teaching and scholarship to inform and persuade science students and other scientists, but do little border crossing into other discourse communities. The prototypical science writer found in this study did not match the image based on a synthesis of the writing literature in that these scientists perceived writing as knowledge telling not knowledge building, their metacognition of written discourse was tacit, and they used a narrow array of genre, strategies, target audiences, and expectations for their writing. © 2002 Wiley Periodicals, Inc.Sci Ed86:672–692, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/sce.10042
Graph‐based tools for re‐engineering
Authors: Cremer Katja , Marburger André , Westfechtel Bernhard 
Published: September 2002

AbstractMaintenance of legacy systems is a challenging task. Often, only the source code is still available, while design or requirements documents have been lost or have not been kept up‐to‐date with the actual implementation. In particular, this applies to many business applications which are run on a mainframe computer and are written in COBOL. Many companies are confronted with the difficult task of migrating these systems to a client/server architecture with clients running on PCs and servers running on the mainframe. REforDI (REengineering for DIstribution) is a graph‐based environment supporting this task. REforDI provides integrated code analysis, re‐design, and code transformation for COBOL applications. To prepare the application for distribution, REforDI assists in the transition to an object‐based architecture, according to which the source code is subsequently transformed into Object COBOL. Internally, REforDI makes heavy use of generators to reduce the implementation effort and thus to enhance adaptability. In particular, graph‐based tools for re‐engineering are generated from a formal specification which is based on programmed graph transformations. Copyright © 2002 John Wiley & Sons, Ltd.
A semantic entropy metric
Authors: Etzkorn Letha H. , Gholston Sampson , Hughes William E. 
Published: September 2002

AbstractThis paper presents a new semantically‐based metric for object‐oriented systems, called the Semantic Class Definition Entropy (SCDE) metric, which examines the implementation domain content of a class to measure class complexity. The domain content is determined using a knowledge‐based program understanding system. The metric's examination of the domain content of a class provides a more direct mapping between the metric and common human complexity analysis than is possible with traditional complexity measures based on syntactic aspects (software aspects related to the format of the code). Additionally, this metric represents a true design metric that can measure complexity early in the life cycles of software maintenance and software development. The SCDE metric is correlated with analyses from a human expert team, and is also compared to syntactic complexity measures. Copyright © 2002 John Wiley & Sons, Ltd.
Syntactic reductions for efficient deadlock analysis
Authors: De Francesco Nicoletta , Santone Antonella 
Published: September 2002

AbstractA well‐known problem in the verification of concurrent systems based on model checking is state explosion: concurrent systems are often represented by automata with a prohibitive number of states. A reduction technique to reduce state explosion in deadlock checking is presented. The method is based on an automatic syntactic simplification of a calculus of communicating systems (CCS) specification, which keeps the parts of the program structure that may lead to a deadlock and deletes the other parts. Copyright © 2002 John Wiley & Sons, Ltd.
Fetotoxicity caused by the interaction between zinc and arsenic in mice
Authors: Fascineli Maria Luiza , Sidney Hunter E. , De Grava Kempinas Wilma 
Published: September 2002

AbstractArsenic is an environmental pollutant that induces congenital malformations in experimental models and can contribute to human birth defects. The environmental exposure to arsenic is relatively small when compared with the doses required to cause teratogenicity in mice and other laboratory animals. In order to study the action of zinc in the arsenic‐induced teratogenicity, in the present work mice were either pretreated with zinc and later with arsenic or were treated simultaneously with zinc and arsenic in vivo and in vitro. Following administration of arsenate on gestation day 8, pregnant females were killed on the 17th day of gestation; maternal and fetal data were collected by laparotomy and used to calculate reproductive parameters. Fetuses were analyzed for the presence of external malformation and, after the appropriate processing, visceral and skeletal analyses were accomplished. Conceptuses were exposed in whole embryo culture to arsenicals on gestation day 8 (3–6 somite stage). After a 26 h culture period, morphological development was assessed. Neither pretreatment with zinc nor simultaneous administration of zinc prevented arsenic teratogenicity in these experimental models. Teratogenesis Carcinog. Mutagen. 22:315–327, 2002. © 2002 Wiley‐Liss, Inc.
Effects of glucose on cloning efficiency and mutagenesis of fetal rat cells
Authors: Donovan Paul J. , Smith George T. , Riggs Charles W. , Alexandrov Valerii A. 
Published: September 2002

AbstractIn a previous study, treatment of rats with 10% glucose in the drinking water, as fetuses during gestation and for 1.5 months after delivery, significantly enhanced tumor incidence that resulted from N‐methyl‐N‐nitrosourea (MNU, 20 mg/kg) given transplacentally on gestation day 21, with a 1.6‐fold increase in overall tumor incidence. We investigated whether glucose would have an effect on MNU‐induced mutation in fetal F‐344 rat somatic cells as measured in an in vivo/in vitro assay. Rat fetuses were exposed transplacentally to MNU on gestation day 16 and to a 10% glucose solution from gestation day 7 to day 17. Cells were isolated on gestation day 17 for determination of cloning efficiency and for selection of 6‐thioguanine (6‐TG)‐resistant HGPRT mutants. Cloning efficiency of the fetal cells exposed to MNU alone was 22.6±2.3% S.E., while that for cells from fetuses exposed to MNU+glucose was 27.5±1.6% S.E., which was a significant difference (P=0.018). This indicates an effect of glucose on cell proliferation and survival. MNU treatment significantly increased the mutation frequency of fetal cells from a spontaneous value of 0.4×10−6 per viable cell to (8.8±1.8 S.E.,)×10−6 (P=0.0087). The coexposure to MNU and glucose yielded a mutant frequency per plate of 0.62±0.05 S.E., which was a 1.5‐fold increase compared to MNU alone (0.43±0.11 S.E., P=0.075. In summary, the data indicate that glucose during pregnancy increases proliferation/survival of fetal cells and possibly also mutation rate. Teratogenesis Carcinog. Mutagen. 22:329–334, 2002. Published 2002 Wiley‐Liss, Inc.
Rat ventral prostate microsomal biotransformation of ethanol to acetaldehyde and 1‐hydroxyethyl radicals: its potential contribution to prostate tumor promotion
Authors: Castro G.D. , Delgado de Layño A.M.A. , Costantini M.H. , Castro J.A. 
Published: September 2002

AbstractRat ventral prostate microsomal fraction was able to biotransform ethanol to acetaldehyde and 1‐hydroxyethyl radicals (1HEt) in the presence of NADPH and oxygen. The enzymatic processes involved were not inhibited by desferrioxamine, CO, SKF 525A, 4‐methylpyrazole, or polyclonal antibody against P450 reductase but they were significantly inhibited by diethyldithiocarbamate, 2‐mercapto‐1‐methylimidazol, thiobenzamide, or diphenyleneiodonium chloride. Results would suggest the partial participation in these ethanol bioactivation processes of flavin containing monooxygenase (FMO) and/or other flavin dependent oxidases/peroxidases and of a non‐iron metal‐containing enzymes. Acetaldehyde and free radicals production by prostate microsomal fraction might potentially contribute to tumor promotion in heavy alcohol drinkers. Teratogenesis Carcinog. Mutagen. 22:335–341, 2002. © 2002 Wiley‐Liss, Inc.
Teratogenic effects of N‐ethyl‐N‐nitrosourea (ENU) on larvae of the self‐fertilizing fish Rivulus marmoratus (Cyprinodontiformes, Rivulidae)
Authors: Lee Jae‐Seong , Chang Sung Yeoul , Kim Il‐Chan , Han Myung‐Soo , Lee Young‐Sik , Lee Yong‐Sung 
Published: September 2002

AbstractWe showed that N‐Ethyl‐N‐Nitrosourea (ENU) induces teratogenesis in larvae of the self‐fertilizing fish Rivulus marmoratus. We discuss this and the issue of carcinogenesis caused by ENU. Teratogenesis Carcinog. Mutagen. 22:363–367, 2002. © 2002 Wiley‐Liss, Inc.
Determination of allelic deletion of multiple endocrine neoplasm type 1 (MEN1) gene in acute myeloid leukemia (AML) by application of FISH‐TSA technique
Authors: Acar Hasan , Kaynak Murat , Yakut Tahsin , Uçar Fahri , Egeli Ünal 
Published: September 2002

AbstractWe have used the single and dual color fluorescence in situ hybridization (FISH) technique combined with a new detection system, tyramide signal amplification (TSA), by using the multiple endocrine neoplasm type 1 (MEN1) gene and chromosome 11 specific alpha satellite DNA probes for the study of the allelic deletion of the MEN1 gene. The MEN1 gene is a new tumor supressor gene and has been recently cloned on chromosome 11q13. FISH combined with the TSA detection system was performed on bone marrow interphase nuclei of 22 patients with acute myeloid leukemia (AML). The FISH‐TSA analysis revealed the mono allelic deletion of the MEN1 gene in 4 out of 22 patients (18.18%), 2 of 9 AML‐M2 patients (22.2%), 1 of 6 AML‐M4 patients (16.6%), and 1 of 4 AML‐M5 patients (25.0%). Our study indicates that allelic deletion of the MEN1 gene is not a major cause or a primary event in tumorigenesis of AML, although the long arm (q13 region) of chromosome 11 involves a chromosomal rearrangement in AML. Teratogenesis Carcinog. Mutagen. 22:369–375, 2002. © 2002 Wiley‐Liss, Inc.
Blocking the translation elongation factor‐1δ with its antisense mRNA results in a significant reversal of its oncogenic potential
Authors: Lei Yi‐xiong , Chen Jia‐kun , Wu Zhong‐liang 
Published: September 2002

AbstractIn spite of the strong evidence for the carcinogenic activity of cadmium and its related compounds, the underlying molecular mechanisms that lead to malignant transformation in cells exposed to cadmium remain unknown. Recently, Joseph et al. [J. Biol. Chem. 227:6131–6136, 2002] have identified, cloned, and characterized the mouse Translation Elongation Factor‐1δ sub‐unit (TEF‐1δ, GenBank Accession Number AF304351) as a novel cadmium‐responsive proto‐oncogene. Presently, additional studies regarding the oncogenic potential of TEF‐1δ have been carried out. Transfection of NIH3T3 cells with the pcDNA3.1 expression vector containing the TEF‐1δ cDNA in the sense (5′→3′) orientation resulted in overexpression of the encoded 31 kDa protein. Transfection‐mediated overexpression of TEF‐1δ protein resulted in transformation of the cells as evidenced from the appearance of transformed foci. Cotransfection of the cells with a mixture of plasmid DNA consisting of TEF‐1δ cDNA in the sense (5′→3′) and in the antisense (3′→5′) orientation resulted in significant inhibition of translation of the TEF‐1δ protein. Antisense TEF‐1δ mRNA‐mediated inhibition of translation of TEF‐1δ protein, furthermore, resulted in inhibition of TEF‐1δ‐mediated transformation of NIH3T3 cells as evidenced from the decrease in the number of transformed foci. These results further confirm that overexpression of TEF‐1δ is oncogenic and the antisense TEF‐1δ mRNA expression reverses its oncogenic potential. Teratogenesis Carcinog. Mutagen. 22:377–383, 2002. © 2002 Wiley‐Liss, Inc.
The managerial issues associated with global account management
Authors: Harvey Michael , Myers Mathew B. , Novicevic Milorad M. 
Published: September 2002

AbstractThe increase in cooperative global arrangements between suppliers and customers has grown precipitously in the

last five years. These global account management (GAM) strategies frequently are brought about due to

the initiative of the global customer, requiring the customer's supplier to manage their total global needs.

In other cases, suppliers perceive GAM as a means to develop long‐term relationships with key global

customers and at the same time hinder competitive inroads. The managerial considerations in implementing and

managing GAM teams are the focus of this article. A step‐by‐step process for management to follow

when implementing a GAM program is also discussed. © 2002 Wiley Periodicals, Inc.
Characterization of the putative maltose transporters encoded by YDL247w and YJR160c
Authors: Day Rachel E. , Higgins Vincent J. , Rogers Peter J. , Dawes Ian W. 
Published: September 2002

AbstractThe maltose permease family of Saccharomyces cerevisiae comprises five proteins, three of which are characterized, MAL31, MAL61 and AGT1 and two putative permeases, YDL247w (MPH2) and YJR160c (MPH3). The two uncharacterized permeases share 100% identity and have 75% identity with MAL31 and MAL61 and 55% identity with AGT1. Characterization of the genes YDL247w and YJR160c confirmed that they encode α‐glucoside permeases capable of transporting maltose, maltotriose, α‐methylglucoside and turanose. Analysis of the promoter regions identified regulatory elements, binding sites for the transcriptional activator, Malx3p and the inhibitory protein, Mig1p. Further analysis of the flanking sequences located blocks of identity covering five open reading frames, indicating that this region was involved in chromosomal block duplication. The members of the maltose permease family are proteins that have strongly overlapping but nevertheless distinct functions, which is a selective advantage for yeast, as it reflects successful adaptation to the variety of environmental conditions to which the yeast cells are exposed; such adaptability is very important in an industrial context. Copyright © 2002 John Wiley & Sons, Ltd.
Physiological role of the second alcohol oxidase gene MOD2 in the methylotrophic growth of Pichia methanolica
Authors: Nakagawa Tomoyuki , Mizumura Tasuku , Mukaiyama Hiroyuki , Miyaji Tatsuro , Yurimoto Hiroya , Kato Nobuo , Sakai Yasuyoshi , Tomizuka Noboru 
Published: September 2002

AbstractThe methylotrophic yeast Pichia methanolica has nine multiple alcohol oxidase (AOD) isozymes, which can be detected on native electrophoretic polyacrylamide gel and are encoded by two genes, MOD1 and MOD2. The aim of this work is to reveal the physiological roles of these AOD subunits, especially that of Mod2p, encoded by the second AOD‐encoding gene, MOD2. A strain expressing only MOD2 showed severe growth inhibition with a low concentration of methanol (0.1%), but its growth was restored with an increase in the methanol concentration (up to 3%). The expression of MOD2 using the CbAOD1 promoter in the Candida boidinii alcohol oxidase‐depleted strain was more advantageous for methylotrophic growth with high methanol concentrations than that of MOD1. The expression of MOD2 was not observed under derepression conditions (0% methanol), and the expression level increased with an increase in the methanol concentration used for induction. The expression of MOD1 was observed under derepression conditions and was rather constant throughout the tested methanol concentration range. Therefore, the ratio of Mod2p to Mod1p in an active AOD octamer was proved to be mainly controlled by changes in the MOD2 mRNA level. These and other results show that Mod2p is a unique AOD subunit more adapted to methylotrophic growth with high methanol concentrations (3%) than Mod1p. Copyright © 2002 John Wiley & Sons, Ltd.
ARL1 and membrane traffic in Saccharomyces cerevisiae
Authors: Rosenwald Anne G. , Rhodes Mary Ann , Van Valkenburgh Hillary , Palanivel Vikram , Chapman George , Boman Annette , Zhang Chun‐jiang , Kahn Richard A. 
Published: September 2002

AbstractTo examine the functions of the Arf‐like protein, Arl1p, in Saccharomyces cerevisiae, a null allele, arl1Δ::HIS3, was constructed in two strains. In one background only, loss of ARL1 resulted in temperature‐sensitive (ts) growth (suppressed on high‐osmolarity media). Allelic variation at the SSD1 locus accounted for differences between strains. Strains lacking ARL1 exhibited several defects in membrane traffic. First, arl1Δ strains secreted less protein as measured by TCA‐precipitable radioactivity found in the media of [35S]‐labelled cells. A portion of newly synthesized carboxypeptidase Y (CPY) was secreted rather than correctly targeted to the vacuole. Uptake of the fluid‐phase marker, lucifer yellow, was reduced. All these phenotypes were exacerbated in an ssd1 background. The ts phenotype of the arl1Δssd1 strain was suppressed by YPT1, the yeast Rab1a homologue, suggesting that ARL1 and YPT1 have partially overlapping functions. These findings demonstrate that ARL1 encodes a regulator of membrane traffic. Copyright © 2002 John Wiley & Sons, Ltd.
Characterization of Ypr1p from Saccharomyces cerevisiae as a 2‐methylbutyraldehyde reductase
Authors: Ford Gordon , Ellis Elizabeth M. 
Published: September 2002

AbstractThe metabolism of aldehydes and ketones in yeast is important for biosynthetic, catabolic and detoxication processes. Aldo‐keto reductases are a family of enzymes that are able to reduce aldehydes and ketones. The roles of individual aldo‐keto reductases in yeast has been difficult to determine because of overlapping substrate specificities of these enzymes. In this study, we have cloned, expressed and characterized the aldo‐keto reductase Ypr1p from the yeast Saccharomyces cerevisiae and we describe its substrate specificity. The enzyme displays high specific activity towards 2‐methylbutyraldehyde, as well as other aldehydes such as hexanal. It exhibits extremely low activity as a glycerol dehydrogenase. The enzyme functions over a wide pH range and uses NADPH as co‐factor. In comparison to other mammalian and yeast aldo‐keto reductases, Ypr1p has relatively high affinity for D,L‐glyceraldehyde (1.08 mM) and hexanal (0.39 mM), but relatively low affinity for 4‐nitrobenzaldehyde (1.07 mM). It displays higher specific activity for 2‐methylbutyraldehyde than does yeast alcohol dehydrogenase and has a Km for 2‐methyl butyraldehyde of 1.09 mM. The enzyme is expressed during growth on glucose, but its levels are rapidly induced by osmotic and oxidative stress. Yeast in which the YPR1 gene has been deleted possess 50% lower 2‐methylbutyraldehyde reductase activity than the wild‐type strain. This suggests that the enzyme may contribute to 2‐methyl butyraldehyde reduction in vivo. It may therefore play a role in isoleucine catabolism and fusel alcohol formation and may influence flavour formation by strains of brewing yeast. Copyright © 2002 John Wiley & Sons, Ltd.