bluuebunny/crossref_metadata_2025_split huggingface dataset:
A distance‐dependent atomic knowledge‐based potential for improved protein structure selection
Authors: Lu Hui , Skolnick Jeffrey 
Published: August 2002

AbstractA heavy atom distance‐dependent knowledge‐based pairwise potential has been developed. This statistical potential is first evaluated and optimized with the native structure z‐scores from gapless threading. The potential is then used to recognize the native and near‐native structures from both published decoy test sets, as well as decoys obtained from our group's protein structure prediction program. In the gapless threading test, there is an average z‐score improvement of 4 units in the optimized atomic potential over the residue‐based quasichemical potential. Examination of the z‐scores for individual pairwise distance shells indicates that the specificity for the native protein structure is greatest at pairwise distances of 3.5–6.5 Å, i.e., in the first solvation shell. On applying the current atomic potential to test sets obtained from the web, composed of native protein and decoy structures, the current generation of the potential performs better than residue‐based potentials as well as the other published atomic potentials in the task of selecting native and near‐native structures. This newly developed potential is also applied to structures of varying quality generated by our group's protein structure prediction program. The current atomic potential tends to pick lower RMSD structures than do residue‐based contact potentials. In particular, this atomic pairwise interaction potential has better selectivity especially for near‐native structures. As such, it can be used to select near‐native folds generated by structure prediction algorithms as well as for protein structure refinement. Proteins 2001;44:223–232. © 2001 Wiley‐Liss, Inc.
Mineralization of 2,4‐D, mecoprop, isoproturon and terbuthylazine in a chalk aquifer
Authors: Kristensen Gitte B , Sørensen Sebastian R , Aamand Jens 
Published: August 2002

AbstractThe potential to mineralize 2,4‐dichlorophenoxyacetic acid (2,4‐D), mecoprop, isoproturon and terbuthylazine was studied in soil and aquifer chalk sampled at an agricultural field near Aalborg, Denmark. Laboratory microcosms were incubated for 258 days under aerobic conditions at 10 °C with soil and chalk from 0.15–4.45 m below the surface. The [ring‐U‐14C]‐labeled herbicides were added to obtain a concentration of 6 µg kg−1and mineralization was measured as evolved [14C]carbon dioxide. The herbicides were readily mineralized in soil from the plough layer, except for terbuthylazine, which was mineralized only to a limited extent. In the chalk, lag periods of at least 40 days were observed, and a maximum of 51%, 33% and 6% of the added 2,4‐D, mecoprop and isoproturon, respectively, were recovered as [14C]carbon dioxide. Large variations in both rate and extent of mineralization were observed within replicates in chalk. No mineralization of terbuthylazine in chalk was observed. As a measure of the general metabolic activity towards aromatic compounds, [ring‐U‐14C]‐benzoic acid was included. It was readily mineralized at all depths.© 2000 Society of Chemical Industry
Cytochromes P450 of insects: the tip of the iceberg
Authors: Scott Jeffrey G , Wen Zhimou 
Published: August 2002

AbstractThe cytochrome P450‐dependent monooxygenases are an extremely important metabolic system involved in the metabolism of endogenous compounds and xenobiotics. Collectively, P450 monooxygenases can metabolize numerous substrates and carry out multiple oxidative reactions. The large number of substrates metabolized is due to the plethora of P450 isoforms and to the broad substrate specificity of some isoforms. Monooxygenases of insects have several functional roles, including growth, development, feeding and protection against xenobiotics, including resistance to pesticides and tolerance to plant toxins. This review begins with background information about P450s and their evolution, followed by a discussion of the extraordinary diversity of insect P450s. Given the enormous interest in studying individual P450s, we then provide a synopsis of the different methods that have been used in their isolation and the substrates that are known to be metabolized. We conclude by summarizing the lessons we have learned from the study of individual insect P450s, including their roles in insecticide resistance, plant–insect interactions and insect physiology. However, these studies are just the ‘tip of the iceberg’. Our knowledge continues to expand at a rapid pace, suggesting that the next decade will outpace the last in terms of improving our understanding of the cytochromes P450 of insects.© 2001 Society of Chemical Industry
Sex‐related differences in the tolerance of Oriental fruit moth (Grapholita molesta) to organophosphate insecticides
Authors: de Lame Frédérique M , Hong Jeon J , Shearer Peter W , Brattsten Lena B 
Published: August 2002

AbstractIn vivo toxicity assays have shown that organophosphate insecticides are less toxic to male than to female Oriental fruit moths Grapholita molesta. While male moths have higher levels of acetylcholinesterase and general esterase activities, female moth acetylcholinesterase enzymes are less sensitive to aromatic and aliphatic organophosphates than male enzymes. Elevated esterase and acetylcholinesterase activities in male moths explain their greater tolerance to aromatic and aliphatic organophosphates. Male and female acetylcholinesterase enzymes are equally tolerant to heteroaromatic organophosphates, the most widely used of this class of insecticides in G molesta control. This observation, in contrast to the greater sensitivity of male acetylcholinesterases to aromatic and aliphatic organophosphates, shows the potential for the evolution of insensitive target sites in male moths, which would increase male G molesta tolerance to these insecticides. Significant sex‐linked differences in insecticide tolerance have not been reported previously in lepidopterans. The practical implications of the observed differences in tolerance in male and female G molesta question the practice of using pheromone traps to monitor populations of these moths in orchards.© 2001 Society of Chemical Industry
Assessment of leaching potential of aldicarb and its metabolites using laboratory studies
Authors: Fava Luca , Bottoni Paola , Crobe Angela , Caracciolo Anna Barra , Funari Enzo 
Published: August 2002

AbstractThe metabolites of pesticides can contaminate groundwater and pose a risk to human health when this water is used for drinking. This paper reports the results of a laboratory study on aldicarb and its main metabolites, aldicarb sulfone and aldicarb sulfoxide. Aldicarb and its metabolites showed Koc values (6–31) which were lower than that of atrazine (55), indicating that they are very mobile in soil. They are less persistent than atrazine (DT50 = 25 days), with DT50 values from less than 1 day and up to 12 days. Aldicarb behaved as a non‐leacher, whereas its metabolites clearly showed the characteristics of leachers. Aged residue leaching experiments showed that aldicarb can occur at high concentrations in the leachate, together with its two metabolites. The leachate composition depends on the incubation time of the parent compound. Aldicarb and its metabolites can form various mixtures in groundwater on the basis of the time elapsing between the application of the insecticide and the first significant rainfall. This study confirms the characteristics of contaminants of aldicarb and especially its metabolites, as reported in the literature.© 2001 Society of Chemical Industry
Design of steel structures under fire conditions
Authors: Bennetts I D , Thomas I R 
Published: August 2002

AbstractChanges have occurred internationally in regulations for fire safety in buildings, and there has been significant recent progress towards rational design for fire safety in buildings. Possible design objectives for fire safety are listed and the interacting factors that influence fire safety in buildings are discussed. A factor of particular importance is fire growth and development, with recent developments in this area leading to increased recognition of non‐uniform conditions occurring in many enclosures of practical significance in fire safety design. Coroner's records and fire statistics have been used to improve our understanding of the factors that lead to casualties (particularly fatalities) in fires, and these have shown that the structure is rarely a factor.Recent progress in understanding and modelling the behaviour of steel structures in fires is reviewed. Recent testing for modern structural steels has resulted in new data for thermal expansion and stress‐related and creep strain, with new mathematical relationships for strain that can easily be used in computer models. Studies of the response of steel columns and composite beams are reviewed, including studies of the effect of temperature gradients and axial restraint on column performance, the development of a simplified equation for concrete‐filled tubular column behaviour and lateral buckling of beams. A major area of recent research is the behaviour in fire of significant parts of a building structure (rather than individual members), particularly in response to the Cardington eight storey steel‐framed building tests. Several recently published approaches to modelling overall structural behaviour are reviewed in the light of these tests.
Engineered durability for timber construction
Authors: Leicester R H 
Published: August 2002

AbstractThe application of reliable prediction models is essential for the development of performance‐based design procedures. Such models for the durability of timber construction are not available. A review of progress in the development of these models reveals that, while models do exist, they must be calibrated with the performance of real structures before they can be used for design. The development of models for predicting performance of constructions under attack by decay fungi, subterranean termites and corrosion is examined.
Acceptable risk bases for design of structures
Authors: Ellingwood Bruce R 
Published: August 2002

AbstractStructural design standards provide the foundation of good engineering practice and a framework for addressing safety and serviceability issues rationally. Structural reliability methods provide the tools for managing uncertainties in modern codified structural design. Current probability‐based structural codes are based on performance measures expressed as notional reliabilities of structural components. These notional reliabilities, encapsulated in reliability indices, were obtained by calibrating the proposed codes to traditional practice rather than from quantitative risk analysis. Because the reliability estimates are based on models of real systems, they may not correspond to historical failure rates, and therefore confound the process of risk communication among structural engineers, building or regulatory officials, and the public. The research and professional engineering communities must work together to confront future challenges arising from new trends in structural engineering practice towards tailoring building design to performance expectations of the building owners, occupants and the public. In this context, the prospects of basing future codes on a quantitative acceptable risk measure warrant further examination.
Brine shrimp lethality assay of Bacopa monnieri
Authors: D'Souza Prashanth , Deepak Mundkinajeddu , Rani Padmaja , Kadamboor Sandhya , Mathew Anjana , Chandrashekar Arun P. , Agarwal Amit 
Published: August 2002

AbstractSuccessive petroleum ether, chloroform, ethanol and water extracts, a saponin rich fraction (SRF) and bacoside A isolated from Bacopa monnieri were tested for brine shrimp lethality. Successive ethanol extracts and SRF showed potent activity. Bacoside A showed the maximum activity with a LC50 of 38.3 μg/mL. The results confirmed the previous reports of an anticancer effect of Bacopa monnieri and suggest bacoside A as the active constituent. Copyright © 2002 John Wiley & Sons, Ltd.
Kava and Valerian in the treatment of stress‐induced insomnia
Authors: Wheatley D. 
Published: August 2002

AbstractKava and valerian are herbal remedies, claimed to have anxiolytic and sedative properties respectively, without dependence potential or any appreciable side‐effects. In this pilot study, 24 patients suffering from stress‐induced insomnia were treated for 6 weeks with kava 120 mg daily. This was followed by 2 weeks off treatment and then, 5 having dropped out, 19 received valerian 600 mg daily for another 6 weeks. Stress was measured in three areas: social, personal and life‐events; insomnia in three areas also: time to fall asleep, hours slept and waking mood. Total stress severity was significantly relieved by both compounds (p < 0.01) with no significant differences between them; as was also insomnia (p < 0.01). The proportion of patients with no side‐effects was 58% with each drug respectively and the ‘commonest’ effect was vivid dreams with valerian (16%), followed by dizziness with kava (12% ). These compounds may be useful in the treatment of stress and insomnia but further studies are required to determine their relative roles for such indications. Copyright © 2001 John Wiley & Sons, Ltd.
Evaluation of the antidiabetic action of Mangifera indica in mice
Authors: Aderibigbe A. O. , Emudianughe T. S. , Lawal B. A. S. 
Published: August 2002

AbstractThe leaves of Mangifera indica were assessed for antidiabetic properties using normoglycaemic, glucose‐induced hyperglycaemia and streptozotocin (STZ) induced diabetic mice. The aqueous extract produced a reduction of blood glucose level in normoglycaemic and glucose‐induced hyperglycaemia, but did not have any effect on streptozotocin‐induced diabetic mice. The hypoglycaemic effect of the aqueous extract was compared with that of an oral dose of chlorpropamide under the same conditions. The results of this study indicate that the aqueous extract of the leaves of Mangifera indica possess hypoglycaemic activity. Copyright © 2001 John Wiley & Sons, Ltd.
Antiradical and antilipoperoxidative effects of some plant extracts used by Sri Lankan traditional medical practitioners for cardioprotection
Authors: J. Munasinghe T. Chaminda , Seneviratne Charita K. , Thabrew M. Ira , Abeysekera Ajith M. 
Published: August 2002

AbstractReactive oxygen species (ROS) are implicated in many pathogenic processes including the cardiovascular system. Detoxification of ROS by antioxidants (AO) therefore affords protection against such diseases. There is a growing body of evidence suggesting that antioxidants contribute to cardioprotection. Therefore, nine plants that are components of Ayurvedic formulations used for the therapy of cardiovascular diseases were investigated to determine whether antioxidant activity is one of the mechanisms by which these plants exert cardioprotection.Initially aqueous freeze dried extracts of the plants were prepared and the antioxidant activity was measured (a) in vitro, by DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) radical scavenging and deoxyribose damage protection assays, and (b) in vivo, by effects on lipid peroxidation. Terminalia arjuna showed significant DPPH radical scavenging activity with EC50 8.3 ± 0.3 Mg/mL (similar to L‐ascorbic acid). The potency of this activity was much lower in Cassia fistula (EC50 = 59.0 ± 2.7 Mg/mL). The other seven extracts demonstrated no such activity in the concentration range tested. In the deoxyribose damage protection assay, T. arjuna> demonstrated no significant effect in the concentration range 0–20 Mg/mL, but above ­20 Mg/mL concentration (20–125 Mg/mL), a pro‐oxidant activity was observed (although markedly less than demonstrated by L‐ascorbic acid). A similar trend was observed with Vitex negundo. In contrast, C. fistula afforded a 30% protection against such damage at 125 Mg/mL concentration. Other plant extracts did not show any activity in this assay. At a dose of 90 mg/kg (single dose) T. arjuna, cardiac lipid peroxidation in male Wistar rats was reduced by 38.8% ± 2.6% (p<0.05) whereas the reduction was only 11.6% ± 3.5% in the case of C. fistula even at a dose of 120 mg/kg.Of all the plants tested, T. arjuna demonstrated the highest antioxidant activity. Overall results show that only some plants used in the therapy of cardiovascular disease exert their beneficial effects via antioxidant activity. Copyright © 2001 John Wiley & Sons, Ltd.
Statistical process monitoring using an empirical Bayes multivariate process control chart
Authors: Feltz Carol J. , Shiau Jyh‐Jen Horng 
Published: August 2002

AbstractIn this paper, we describe the theory underlying an empirical Bayesian approach to monitoring two or more process characteristics simultaneously. If the data is continuous and multivariate in nature, often the multivariate normal distribution can be used to model the process. Then, using Bayesian theory, we develop techniques to implement empirical Bayes process monitoring of the multivariable process. Lastly, an example is given to illustrate the use of our techniques. Copyright © 2001 John Wiley & Sons, Ltd.
Assessment of a capability index sensitive to skewness
Authors: Nahar P. C. , Hubele N. F. , Zimmer L. S. 
Published: August 2002

AbstractFor many quality characteristics, such as circularity, cylindricity, straightness and flatness, positive skewness in the inspection data is the norm, and, in fact, is desirable. Summarizing the process performance using such data in conjunction with capability indices has recently received a considerable amount of attention, with new indices being proposed and compared for usefulness and accuracy. This paper is intended to contribute to this growing discussion, and to add a unique focus. In particular, this investigation concentrates on one form of a neoclassical index, the Cs index, originally proposed to be sensitive to skewness and to decrease in value as the skewness increased in the underlying distribution of the data. In other words, ‘skewness is badness’. Looking at this index from an altered perspective, the possibility that this index could serve a useful purpose in summarizing process performance for such non‐normal processes by merely changing its interpretation or slightly changing its form is considered. Hence, actual data from circularity measurements are used to identify a relevant group of distributions, and then the accuracy of Cs is investigated along with its modified version for this group of distributions. In particular, this investigation includes several Rayleigh and gamma distributions for various sample sizes and reports on the bias of the proposed estimators. These findings indicate that such a modified index has some useful attributes in reflecting process performance, with respect to the percentage of non‐conformance and the accuracy for relatively large samples. Copyright © 2001 John Wiley & Sons, Ltd.
Interaction of acetonitrile with alkaline metal cations: A density functional, coupled‐cluster, and quadratic configuration interaction study
Authors: Pejov Ljupčo 
Published: August 2002

AbstractA systematic quantum chemical study of CH3CN and its CH3CNM+ 1:1 model adducts (M+∈{Li+, Na+}) is presented, with respect to binding energetics, structural and vibrational force field changes. Several gradient‐corrected density functional levels of theory were employed (of both “pure” and “hybrid” character), together with the coupled cluster including double substitutions from the Hartree–Fock determinant (CCD) and quadratic configuration interaction including single and double substitutions (QCISD) methods [with the rather large 6‐311G(d,p) basis set], and their performances compared. The binding energy decompositions according to the Kitaura–Morokuma scheme and the reduced variational space self‐consistent field (RVS‐SCF) method have shown that the electrostatic plus polarization interaction terms are primarily responsible for overall stabilization, while the charge‐transfer term is negligibly small and virtually identical for both adducts. The computed harmonic vibrational frequencies for acetonitrile correlate excellently with the experimental ones (r2>0.9998 for almost all cases, while for the BLYP level, r2=1). It is shown for the first time that the experimentally observed blue shifts of the νCN mode are caused even by formation of 1:1 adducts, contrary to the previously accepted opinions. The CCD and QCISD, as well as the BPW91 and BP86 levels of theory predict almost excellently the νCN mode blue shift upon adduct formation, while the BLYP and B3LYP levels perform significantly poorer. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
On the relationship between the one‐electron and Bohm's quantum potential
Authors: Kohout M. 
Published: August 2002

AbstractThe one‐electron potential, derived from the electron density, is a three‐dimensional function, whereas Bohm's quantum potential depends on the spatial coordinates of all involved electrons. To analyze the relationship between the two potentials in the many‐electron case, first the dimensionality of the quantum potential needs to be reduced to match that of the one‐electron potential. A possible approach for such dimensionality reduction by calculating the expectation value of the quantum potential over all but one electron, using the factorization of the real part of the wave function into a marginal and conditional function is presented, and a relation between such three‐dimensional local quantum potential and the one‐electron potential is given. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
GRECP/MRD‐CI calculations on the Hg atom and HgH molecule
Authors: Mosyagin N. S. , Titov A. V. , Buenker R. J. , Liebermann H.‐P. , Alekseyev A. B. 
Published: August 2002

AbstractMultireference single‐ and double‐excitation configuration interaction (MRD‐CI) calculations of transition energies for the Hg atom and spectroscopic constants for the HgH molecule are carried out with the generalized relativistic effective core potential (GRECP) method. A new selection criterium for the reference configurations is discussed. The calculated spectroscopic constants are compared with experimental data and results of calculations of other groups. Improvement of accuracy is mainly observed for bond lengths from the GRECP/MRD‐CI calculations (without applying the T = 0 correction) with respect to the results of other groups. Analysis of the quality of the approximations employed is carried out. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002
Computed electrostatic potentials and average local ionization energies on the molecular surfaces of some tetracyclines
Authors: Hussein Wedad , Walker Christopher G. , Peralta‐Inga Zenaida , Murray Jane S. 
Published: August 2002

AbstractThe electrostatic potentials and average local ionization energies computed on the molecular surfaces of four tetracyclines have been investigated with the objective of identifying common features as well as subtle differences that may be related to their biological activities. The four are the parent molecule tetracycline, chlortetracycline, oxytetracycline, and doxycyline. The calculations were carried out at the HF/STO‐3G*//STO‐3G* level. Our electrostatic potential results show that each molecule has a large negative region that extends along its lower portion, consistent with its ability to complex Ca2+ and Mg2+ ions. Although the surface electrostatic potentials of the four tetracyclines show many similarities, our statistical measure of local polarity allows us to label doxycycline as the one with the lowest degree of local polarity, consistent with its longer half‐life in vivo. The regions in the tetracyclines with the most reactive electrons are the amide nitrogen lone pairs and certain carbons of the outermost rings. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 82: 160–169, 2001