bluuebunny/crossref_metadata_2025_split huggingface dataset:
1H and 13C NMR conformational study of 2‐(benzotriazol‐1‐yl)‐substituted tetrahydrofurans
Authors: Katritzky Alan R. , Akhmedov Novruz G. , Ghiviriga Ion , Denisko Olga V. , Steel Peter J. 
Published: February 2003

AbstractAssignments of the proton and carbon NMR signals for 2‐(benzotriazol‐1‐yl)tetrahydrofurans 1–6 are based on 1H–1H COSY, NOESY, 1H–13C heteronuclear HETCOR, 1H–13C heteronuclear long‐range HETCOR‐LR and nuclear Overhauser enhancement experiments, and supported by selective spin decoupling experiments. The electronic and steric effects of the 2‐benzotriazolyl substituent on the 1H and 13C NMR chemical shifts are evaluated and discussed. Conformational isomers cis and trans are distinguished by the magnitude of the J(H−2,H−3) coupling constant, by one‐bond 1J(C−2, H−2) coupling constants and by 13C chemical shifts of the C‐2 anomeric carbon. The benzotriazol‐1‐yl group prefers the pseudo‐axial orientation in each of 1–6. The stereochemistry and conformation of 6 are rigorously demonstrated by an x‐ray structure. Copyright © 2003 John Wiley & Sons, Ltd.
Cyclopropylbenzene ring opening by chlorine atom: radicals or radical ions?
Authors: Trukhin Aleksei V. , Eliseenkov Evgeny V. , Dneprovskii Aleksei S. 
Published: February 2003

AbstractCyclopropylbenzene radical chlorination leads to hydrogen atom abstraction and to ring opening. The contribution of the last process is increased in the presence of acids and in polar solvents. It is suggested that the ring opening process proceeds via radical cation formation by single electron transfer from cyclopropylbenzene to the chlorine atom in the first stage of reaction. Copyright © 2003 John Wiley & Sons, Ltd.
Theoretical study of the gas‐phase decomposition of neutral α‐amino acid ethyl esters. Part 2—Elimination of ethyl picolinate and ethyl 1‐methylpipecolinate
Authors: Notario Rafael , Quijano Jairo , León Luis A. , Sánchez Claudia , Quijano J. Camilo , Alarcón Gustavo , Chamorro Eduardo , Chuchani Gabriel 
Published: February 2003

AbstractTheoretical studies of the thermolysis in the gas phase of two α‐amino acid ethyl esters, ethyl picolinate and ethyl 1‐methylpipecolinate, were carried out using ab initio theoretical methods, at the MP2/6–31G(d) and MP2/6–311+G(2d,p) levels of theory. The reactions studied have two steps: the first corresponds to the formation of a neutral amino acid intermediate via a six‐membered cyclic transition state, and the second is the rapid decarboxylation of this intermediate via a five‐membered cyclic transition state. The progress of the first step of the reactions was followed by means of the Wiberg bond indices. The results indicate that the transition states have an intermediate character between reactants and products, and the calculated synchronicities show that the reactions are concerted and slightly asynchronous. The bond‐breaking processes are more advanced than the bond‐forming processes, indicating a bond deficiency in the transition states. The kinetic parameters calculated for both reactions agree very well with the available experimental results. Copyright © 2003 John Wiley & Sons, Ltd.
Theory and example of a small‐molecule motor
Authors: Mock William L. , Ochwat Krzysztof J. 
Published: February 2003

AbstractConceptual principles for operation of a molecular motor stipulate that such a species must consist of an energy‐consuming catalyst that exhibits within its mechanism temporal overlap of successive catalytic cycles, so as to induce irreversible intramolecular motion during operation. The exothermic hydration reaction of MeCOCHCNCMe3 brought about by catalyst HO2CCH2OCMe(CO2H)2 qualifies as such a process, in the form of serial conversion between canonical carboxylic anhydride structures within the catalyst. The steady‐state kinetic behavior and inactivation by methanol demonstrate the operation of an appropriate repetitive catalytic loop in this case. Copyright © 2003 John Wiley & Sons, Ltd.
A new blue light‐emitting oligofluorene glass: synthesis, characterization and photophysical properties
Authors: Belfield Kevin D. , Bondar Mykhailo V. , Morales Alma R. , Yavuz Ozlem , Przhonska Olga V. 
Published: February 2003

AbstractThe synthesis, electrochemical, thermal and spectroscopic properties of the oligoaminofluorene derivative 9,9‐didecyl‐N,N‐bis(9,9‐didecyl‐7‐N,N‐diphenylaminofluoren‐2‐yl)‐N,N‐diphenylfluorene‐2,7‐diamine (4), an organic glass, were investigated in solvents of differing polarity at room and 77 K temperature, including quantum yield and lifetime. The oligomer exhibited a glass transition near room temperature and was thermally stable to ca 400 °C. Intramolecular interactions between the fluorenyl chromophores were investigated. The relatively complex nature of the emission band of 4 was characterized by reduced anisotropy and two components in its fluorescence decay at room temperature. Emission spectra of 4 at 77 K exhibited a single component in its fluorescence decay and a dependence on the excitation wavelength at the red edge of the absorption band. A spectroscopic model of 4 is proposed to explain the observed spectral behavior of this potentially important electroluminescent material. Copyright © 2003 John Wiley & Sons, Ltd.
Correlation analysis between equilibria for addition of semicarbazide and hydroxylamine to several carbonyl compounds and their equilibria for addition of water
Authors: Malpica A. , Calzadilla M. 
Published: February 2003

AbstractEquilibrium constants for semicarbazide and hydroxylamine addition to several carbonyl compounds are reported and compared with those for addition of water. The results are correlated by the linear free relationship log Kadd = Sw + B, where w is a measure of the reactivity of a given compound to water addition, S is a measure of the sensitivity of the examined reactions compared with the model of hydration equilibrium constants and B is a constant for a given reaction series. Copyright © 2003 John Wiley & Sons, Ltd.
Fabrication of Ordered Macroporous Structures Based on Hetero-Coagulation Process Using Nanoparticle as Building Blocks
Authors: Tang Fengqiu , Fudouzi Hiroshi , Uchikoshi Tetsuo , Awane Toru , Sakka Yoshio 
Published: February 2003

Abstract
A simple method based on hetero-coagulation process for the preparation of well-defined ordered macroporous inorganic materials from nanoparticles and spherical polymer templates is reported.
Cyclodextrin-induced Color Changes in Polymerized Diacetylene Langmuir-Schaefer Films
Authors: Cho Jae-Taek , Woo Sung-Min , Ahn Dong June , Ahn Kwang-Duk , Lee Haiwon , Kim Jong-Man 
Published: February 2003

Abstract
We have observed the first example of a cyclodextrin-induced color change of polymerized diacetylene film sensor. The PDA film, prepared from a diacetylene monomer containing a terminal anilide moiety was found to preferentially interact with α-cyclodextrin causing a color transition which is both time and concentration dependent.
Optimization of an industrial afterburner
Authors: Öberg Tomas 
Published: February 2003

AbstractAn industrial afterburner was optimized using statistical experimental design. A computer‐generated optimal design was adapted to domain constraints and previous knowledge about the experimental variables. Carbon monoxide was used as a general indicator for the operating conditions, and a reduced response surface model was fitted to the experimental data. In a second phase the initial results were verified and investigated in more detail with regard to chlorinated aromatics. The empirical models obtained were further interpreted using results from laboratory investigations and more fundamental knowledge from combustion theory. Copyright © 2003 John Wiley & Sons, Ltd.
Centering and scaling in component analysis
Authors: Bro Rasmus , Smilde Age K. 
Published: February 2003

AbstractIn this paper the purpose and use of centering and scaling are discussed in depth. The main focus is on two‐way bilinear data analysis, but the results can easily be generalized to multiway data analysis. In fact, one of the scopes of this paper is to show that if two‐way centering and scaling are understood, then multiway centering and scaling is quite straightforward. In the literature it is often stated that preprocessing of multiway arrays is difficult, but here it is shown that most of the difficulties do not pertain to three‐ and higher‐way modeling in particular. It is shown that centering is most conveniently seen as a projection step, where the data are projected onto certain well‐defined spaces within a given mode. This view of centering helps to explain why, for example, centering data with missing elements is likely to be suboptimal if there are many missing elements. Building a model for data consists of two parts: postulating a structural model and using a method to estimate the parameters. Centering has to do with the first part: when centering, a model including offsets is postulated. Scaling has to do with the second part: when scaling, another way of fitting the model is employed. It is shown that centering is simply a convenient technique to estimate model parameters for models with certain offsets, but this does not work for all types of offsets. It is also shown that scaling is a way to fit models with a weighted least squares loss function and that sometimes this change in objective function cannot be performed by a simple scaling step. Further practical aspects of and alternatives to centering and scaling are discussed, and examples are used throughout to show that the conclusions in the paper are not only of theoretical interest but can have an impact on practical data analysis. Copyright © 2003 John Wiley & Sons, Ltd.
Multivariate data analysis: quo vadis?
Authors: Esbensen Kim H. , Höskuldsson Agnar 
Published: February 2003

AbstractIndustry and academe are characterized by steadily increasing huge amounts of data with very different data structures. Both static and dynamic data contexts need to be addressed. A new generic, flexible and comprehensive general data‐modelling concept is needed to cope with these demands. During the past 20 years, object‐oriented programming (OOP) has become a de facto industry standard of how programming tasks should be defined and carried out in the context of deterministic data modelling. We present here a first framework of analogous ideas for multivariate data analysis. A new strategy, object‐oriented data modelling (OODM), is proposed which is invariant with respect to the specific data structures and the practical data context. We present a first delineation of meta‐principles, ideas and stimulants for tomorrow's possible development paths of modelling, in which the fundamental data analysis unit is the generalized ‘PLS object’ in the OOP sense. The key novel aspect concerns inter‐object information transfer, facilitated by ‘root‐sum‐of‐squares averaging’ (RSSA), which uses w loading weights as between‐object transfer agents. These features allow a powerful generalization beyond multiblock as well as hierarchical bilinear modelling to be laid out. The present part I outlines a first framework for the new data‐modelling approach, while part II forms a complementing catalogue of specific options and possibilities when implementing the new principles. Copyright © 2003 John Wiley & Sons, Ltd.
O2‐PLS, a two‐block (X–Y) latent variable regression (LVR) method with an integral OSC filter
Authors: Trygg Johan , Wold Svante 
Published: February 2003

AbstractThe O2‐PLS method is derived from the basic partial least squares projections to latent structures (PLS) prediction approach. The importance of the covariation matrix (Y
TX) is pointed out in relation to both the prediction model and the structured noise in both X and Y. Structured noise in X (or Y) is defined as the systematic variation of X (or Y) not linearly correlated with Y (or X). Examples in spectroscopy include baseline, drift and scatter effects. If structured noise is present in X, the existing latent variable regression (LVR) methods, e.g. PLS, will have weakened score–loading correspondence beyond the first component. This negatively affects the interpretation of model parameters such as scores and loadings. The O2‐PLS method models and predicts both X and Y and has an integral orthogonal signal correction (OSC) filter that separates the structured noise in X and Y from their joint X–Y covariation used in the prediction model. This leads to a minimal number of predictive components with full score–loading correspondence and also an opportunity to interpret the structured noise. In both a real and a simulated example, O2‐PLS and PLS gave very similar predictions of Y. However, the interpretation of the prediction models was clearly improved with O2‐PLS, because structured noise was present. In the NIR example, O2‐PLS revealed a strong water peak and baseline offset in the structured noise components. In the simulated example the O2‐PLS plot of observed versus predicted Y‐scores (u vs u
hat) showed good predictions. The corresponding loading vectors provided good interpretation of the covarying analytes in X and Y. Copyright © 2003 John Wiley & Sons, Ltd.
Multivariate analysis of G protein‐coupled receptors
Authors: Gunnarsson Ingrid , Andersson Per , Wikberg Jarl , Lundstedt Torbjörn 
Published: February 2003

AbstractWith the rapidly increasing amount of data of a bioinformatic nature, it is of great interest to find different methods to help overview, classify, identify outliers and in other ways extract information from the large amounts of data. In this paper, chemometric methods often applied in statistical process control are utilized to analyse a large number of G protein‐coupled receptors. They have been investigated with respect to groupings among the sequences based on their physicochemical properties using multivariate methods. The transmembrane (TM) regions of 897 receptors were examined. The sequences were multivariately characterized using principal properties for amino acids. The methods used include principal component analysis (PCA), hierarchical principal component analysis (HPCA) and partial least squares projections to latent structures (PLS). The results show that groups of receptors belonging to the same functional class can be identified using this approach, and that the rhodopsin class of G protein‐coupled receptors is very different from other classes present in the study with regard to their physicochemical properties. Copyright © 2003 John Wiley & Sons, Ltd.
Multivariate data analysis: quo vadis?
Authors: Höskuldsson Agnar , Esbensen Kim H. 
Published: February 2003

AbstractIn part I we presented an analysis of the situation facing multivariate data analysis at the turn of the
millenium. As a direct analogy to object‐oriented programming we presented similar
ideas for multivariate data analysis, resulting in a proposal for a new paradigm for
object‐oriented data modelling (OODM), which is invariant w.r.t. data
structures and practical data contexts. In this part II we give a first overview of tomorrow's
meta‐principles, ideas and stimulants for the implementation of multivariate OODM. This is
exemplified by analysing the typical objectives behind data modelling, and we give numerous
suggestions for what may be important development areas for the near future. We have
arranged the many disparate data analysis objectives in a series of ‘levels of modelling’
in an attempt to make a systematic categorization. Copyright © 2003 John Wiley & Sons,
Ltd.
Socially responsible investment in the UK—criteria that are used to evaluate suitability
Authors: Jayne Michael Ross , Skerratt Glynn 
Published: February 2003

AbstractEthical and environmental investment criteria, collectively grouped under the title socially responsible investment (SRI), are becoming increasingly important factors in today's markets. Nowadays, banks, pension funds and other investment institutions frequently undertake some form of environmental risk analysis of an organization's relevant operational practices before committing themselves to direct investment. Factors such as a company's past pollution record, its future potential to contaminate and its overall social policy are often cited as important influences in this respect.Many funding institutions now have their own ethical investment arms, even if these are not part of their mainstream activity. Understanding the role of ‘ethical’ investors and their ‘ethical’ considerations is becoming increasing important to fund managers and businesses alike.The activities of fund managers who are specifically marketing themselves and their products as ‘ethical’ have been explored using an in‐depth questionnaire, in order to determine the nature of the environmental and sustainability criteria that are used as a basis for directing investments, and the ways in which these factors are compared and balanced during the evaluation process. Copyright © 2003 John Wiley & Sons, Ltd. and ERP Environment.
Should we measure corporate social responsibility?
Authors: Korhonen Jouni 
Published: February 2003

AbstractThis paper is critical towards efforts that try and measure corporate social responsibility (CSR). A critical approach can be important for the development of the theory of the emerging field of corporate social responsibility. A critical and provocative approach can generate discussion and debate. Three main points of critique are presented toward the current efforts in the literature to measure corporate contributions to economic, social and ecological sustainability. First, the use of the concepts of eco‐efficiency and eco‐efficacy in measuring corporate contributions to sustainability are criticized from the viewpoint of the complementarity relation of human‐manufactured capital, natural capital and social sustaining functions. Second, the use of measures that focus on an individual process or an individual company are reconsidered with an approach to industrial and firm networks. Third, the use of the monetary value is reconsidered, e.g. by suggesting an approach based on physical material and energy flows and on a new paradigmatic foundation for social responsibility. The social and ecological indicators illustrating the social and environmental impacts of economic activity and of firms can be combined with economic indicators, but not expressed in monetary terms. Copyright © 2003 John Wiley & Sons, Ltd. and ERP Environment.
Gene expression profiling in islet biology and diabetes research
Authors: Bernal‐Mizrachi Ernesto , Cras‐Méneur Corentin , Ohsugi Mitsuru , Permutt M. Alan 
Published: February 2003

AbstractFollowing the sequencing of most of the human and mouse genomes, the next task for physicians and scientists will be to assess the relative levels of expression of these genes during development, following exposure to various nutritional and pharmacological conditions, and in disease states such as diabetes and related metabolic disorders. This review provides an overview of the various methodologies available for monitoring global gene expression. Use of cDNA libraries, Expressed Sequence Tag (EST)equencing projects and databases, differential display (DD), serial analysis of gene expression (SAGE), subtractive cloning, and both cDNA and oligo microarrays are discussed, along with their merits and limitations. The Endocrine Pancreas Consortium http://www.cbil.upenn.edu/EPConDB/ has constructed mouse and human cDNA libraries from adult and various stages of embryonic development of endocrine pancreas. Over 100 000 ESTs have been deposited in public databases, and each clone is available through the IMAGE Consortium. A guide to Internet access is provided for future investigation. Copyright © 2002 John Wiley & Sons, Ltd.
The prevalence of coeliac disease in Libyan children with type 1 diabetes mellitus
Authors: Ashabani Abdelhakim , Abushofa Umaima , Abusrewill Suliman , Abdelazez Mahmoud , Tučková Ludmila , Tlaskalová‐Hogenová Helena 
Published: February 2003

AbstractBackgroundDiagnosis of atypical and silent forms of coeliac disease (CD) is important because of its serious complications. Increased prevalence of coeliac disease worldwide in individuals with type 1 diabetes mellitus (DM) was described. There are no data on the prevalence of CD in the Libyan population and Libyan DM patients. The aim of this study was to test the occurrence of CD‐related markers in a group of Libyan children with DM.MethodsA cohort of 234 Libyan children with DM (121 males and 113 females) aged between 2 and 25 years and 50 healthy school children were screened for CD using the enzyme‐linked immunosorbent assay (ELISA) for IgA and IgG antigliadin (AGA), anti‐tissue transglutaminase (tTG), and anticalreticulin antibodies. An IgA antiendomysial antibody (EmA) was determined by immunofluorescence.ResultsFifty patients (21.3%) were positive for IgA‐ and/or IgG‐AGA, tTG, and anticalreticulin antibodies. Nineteen of these patients were EmA positive and seven were EmA negative. From the EmA negative patients we found that five sera with IgA deficiency had high IgG class in antigliadin, anti‐tissue transglutaminase, and anticalreticulin antibodies. All these patients underwent intestinal biopsy. Twenty‐four had clear histological (atrophy) evidence of CD including the EmA negative patients with IgA deficiency; prevalence of CD in this study was thus 10.3%.ConclusionThe prevalence of CD in diabetic children in Libya was found to be higher than in several European countries. Serological markers are useful for identifying DM patients who should undergo a small intestinal biopsy. Copyright © 2002 John Wiley & Sons, Ltd.
Ascorbic acid supplementation restores defective leukocyte‐endothelial interaction in alloxan‐diabetic rats
Authors: Onishi Zanardo Renata Cristina , Cruz José Walber Miranda Costa , de Oliveira Maria Aparecida , Fortes Zuleica Bruno 
Published: February 2003

AbstractBackgroundDefective leukocyte‐endothelial interactions are observed in experimental diabetes and may reduce the capacity to mount an adequate inflammatory response. The present study investigated the effect of ascorbic acid, an inhibitor of free radical and glycated protein formation as well as an aldose reductase inhibitor, on leukocyte‐endothelial interaction in alloxan‐diabetic rats.MethodsRats were rendered diabetic by alloxan injection (40 mg/kg; iv). After 30 days, diabetic and nondiabetic controls were supplemented for 12 days with ascorbic acid (50 or 200 mg/kg/day) or received saline by gavage. The number of rollers, stickers after zymosan‐activated plasma (10%) or leukotriene B4 (1 µM) applied topically, and migrated cells after local injection of carrageenan (100 µg) were determined in the venules of the internal spermatic fascia by intravital microscopy. Erythrocyte velocity and wall shear rate were determined as well. Reactive oxygen species formation by endothelial cells was measured in vivo by the same technique. Immunocytochemistry for ICAM‐1 detection on the endothelium of the venules of the internal spermatic fascia was carried out in cross sections of the whole testis of the animals.ResultsThe reduced number of rollers, stickers and migrated cells, as well as the higher production of reactive oxygen species by endothelial cells in diabetic rats was corrected by ascorbic acid supplementation. The low immunoreactivity for ICAM‐1 in the venules of diabetic rats was improved by ascorbic acid supplementation. Ascorbic acid supplementation did not interfere with erythrocyte velocity or wall shear stress. Ascorbic acid administered to control rats did not alter the parameters studied above.ConclusionWe conclude that ascorbic acid improves leukocyte‐endothelial interaction in diabetic rats at least in part by restoring the expression of ICAM‐1 in the venules of diabetic rats. Copyright © 2002 John Wiley & Sons, Ltd.