bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculating populations of subcellular compartments using density matrix formalism
Authors: Alexandrov Vadim , Gerstein Mark
Published: August 2002

In our earlier paper (Ref. 1) we developed an integrated probabilistic system for predicting the subcellular localization of proteins and estimating the relative populations of the various compartments in yeast. To justify our formulas we show here that there is a one‐to‐one correspondence between our previous calculations and the prediction of a state of a many‐particle quantum system. The equivalence between these two types of predictions can be easily established if one maps the probability of finding a particular protein in a certain subcellular compartment to the probability of measuring the corresponding quantum particle in one of the possible quantum states (the number of proteins being equal to the number of particles in the system, and the number of compartments being equal to the number of achievable quantum states). Once the sought correspondence is established, we can utilize a well‐known formula from quantum statistical mechanics to calculate the overall occupation of a particular quantum state, associating the state with the corresponding subcellular compartment. In the present work we present the details of how we arrived at the formula for the compartment population, borrowing the tools from quantum statistical mechanics. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Ladder operators for the modified Pöschl–Teller potential
Authors: Dong Shi‐Hai , Lemus R.
Published: August 2002

A closed form of the normalization constants of the wave function for the modified Pöschl–Teller (MPT) potential is obtained from two different methods. It is shown that the discrete spectrum of the MPT potential is associated to the su(2) algebra. This identification is achieved by means of a realization of raising and lowering operators in terms of the physical variable u=tanh (αx). Analytical expressions for the matrix elements derived from these operators are obtained for the functions \documentclass{article}\pagestyle{empty}\begin{document}$u/{\sqrt{1-u^{2}}}$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$\sqrt{1-u^{2}}\,(d/du)$\end{document}. The harmonic limit of the su(2) operators is also analyzed. © 2002 John Wiley & Sons, Inc. Int J Quantum Chem 86: 265–272, 2002
Modification of a commercial electrospray nebulizer for operation in a liquid chromatography/mass spectrometry system at flow rates in the low µL/min range
Authors: Carrier Alain , Parent Josée
Published: August 2002

A simple and inexpensive approach to convert the electrospray nebulizer of a commercial liquid chromatography/mass spectrometry (LC/MS) system (HP 1100) to accommodate lower flow rates has been proposed and evaluated. This modification consists of simply replacing the nebulizer needle by a commercially available stainless steel needle with a smaller internal diameter. Experiments were conducted in order to optimize operational parameters. Using two different internal diameter needle sizes, flow rates ranging from 1 to 250 µL/min could be accommodated. The modification presented allows an extension of the range of compatible flow rates without major modification of the standard design of the interface. Copyright © 2001 John Wiley & Sons, Ltd.
Electrolytic electrospray ionization mass spectrometry of C60‐TTF‐C60 derivatives: high‐resolution mass measurement and molecular ion gas‐phase reactivity
Authors: Rondeau David , Kreher David , Cariou Michel , Hudhomme Piétrick , Gorgues Alain , Richomme Pascal
Published: August 2002

The electrochemical process involved in electrospray ionization is used to obtain odd‐electron molecular ions from C60‐TTF‐C60 and its methano derivatives. Exact mass measurements obtained using high‐resolution mass spectrometry are reported, and the gas‐phase behavior of the radical cation (retro‐Diels‐Alder reaction and [M/2 + H]+ ion formation) is described. Copyright © 2001 John Wiley & Sons, Ltd.
Optimization of quartz tube pyrolysis atmospheric pressure ionization mass spectrometry for the generation of bacterial biomarkers
Authors: Tripathi Ashish , Maswadeh Waleed M. , Snyder A. Peter
Published: August 2002

Experimental procedures were investigated to improve the efflux of biomolecule pyrolyzates from quartz tube pyrolysis under atmospheric pressure ionization mass spectrometry conditions. Heating regimes, airflows, and ion focusing parameters were optimized to increase the informative mass spectral signals generated from the pyrolysis of Gram‐positive bacterial spores and vegetative cells. Dipicolinic acid (DPA) is found in 5–15% by weight in Gram‐positive Bacillus spores, and the parameter optimization procedures provided an intense mass spectral signature of the m/z 168 protonated DPA molecule with a minimization of pyrolytic and ionization fragments. Moreover, mass spectral information from the optimization protocols yielded peaks and mass patterns characteristic of DNA and RNA nitrogen bases, protein diketopiperazines, and amino sugars. Copyright © 2001 John Wiley & Sons, Ltd.
Stabilization of a class of uncertain nonlinear affine systems subject to control constraints
Authors: Goodall D. P. , Wang J.
Published: August 2002

Practical and asymptotic stabilization is investigated for a class of uncertain nonlinear affine control systems subject to constraints on the control inputs. The uncertain systems are modelled as non‐linear perturbations to a known non‐linear idealized system and a problem formulation based on differential inclusions is adopted. A class of constrained generalized state‐feedback controls (containing both continuous and discontinuous selections) is developed, which guarantees stabilization with a specified region of attraction. In the presence of residual uncertainty, sufficient conditions for global stabilizability are presented, whilst local results are obtained by relaxing these conditions. Copyright © 2001 John Wiley & Sons, Ltd.
State‐feedback H∞ control of nonlinear singularly perturbed systems
Authors: Fridman E.
Published: August 2002

We study the H∞ control problem for an affine singularly perturbed system, which is nonlinear in the state variables. Under suitable assumptions on the linearized problem, we construct ε‐independent composite and linear controllers that solve the local H∞ control problem for the full‐order system for all small enough ε. These controllers solve also the corresponding problem for the descriptor system. The ‘central’ nonlinear controller can be approximated in the form of expansions in the powers of ε. An illustrative example shows that the higher‐order approximate controller achieves the better performance, while the composite (zero‐order approximate) controller leads to the better performance than the linear one. Copyright © 2001 John Wiley & Sons, Ltd.
Cadenced runs of impulse and hybrid control systems
Authors: Aubin Jean‐Pierre , Haddad Georges
Published: August 2002

Impulse differential inclusions, and in particular, hybrid control systems, are defined by a differential inclusion (or a control system) and a reset map. A run of an impulse differential inclusion is defined by a sequence of cadences, of reinitialized states and of motives describing the evolution along a given cadence between two distinct consecutive impulse times, the value of a motive at the end of a cadence being reset as the next reinitialized state of the next cadence.

A cadenced run is then defined by constant cadence, initial state and motive, where the value at the end of the cadence is reset at the same reinitialized state. It plays the role of a ‘discontinuous’ periodic solution of a differential inclusion.

We prove that if the sequence of reinitialized states of a run converges to some state, then the run converges to a cadenced run starting from this state, and that, under convexity assumptions, that a cadenced run does exist. Copyright © 2001 John Wiley & Sons, Ltd.
Quantitative non‐diagonal controller design for multivariable systems with uncertainty
Authors: García‐Sanz M. , Egaña I.
Published: August 2002

The loop coupling reduction of multivariable systems under the presence of plant uncertainty is currently a most discussed topic. Following the ideas suggested by Horowitz, in this paper the role played by the non‐diagonal controller elements is analysed in order to state a design methodology. Thus, the definition of a coupling matrix and a quality function of the non‐diagonal elements come into use to quantify the amount of loop interaction and to design the controllers, respectively. This yields a criterion that makes possible to propose a sequential design methodology of the fully populated matrix controller, in the quantitative feedback theory (QFT) robust control frame. Finally, a real example with the heat exchanger of a pasteurization plant is included to show the practical use of this technique. Copyright © 2002 John Wiley & Sons, Ltd.
Propagation phase noise and impact on future VSAT system design
Authors: Vilar E. , Catalan C.
Published: August 2002

The concepts of propagation phase and fm noise are presented comparing oscillator noise with phase fluctuations introduced by the propagation medium. Numerical values of the spectral density and variance are presented. Values of the excess propagation phase noise are presented for measurements obtained at 40 GHz using the F40 Italsat beacon. The ultimate effect of the propagation phase noise is analysed for its effects in (i) a carrier acquisition system and (ii) the irreducible error rate of a digital communications system using MPSK or MQAM constellations. Several parametric studies are given illustrating the use of the expressions and curves obtained, and a way forward for the future analysis of optimization of data rate and throughput is presented. Recommendations are given as regards the future short‐term stability improvement of satellite on board oscillators with implications for the future use of laptop type of portable VSAT stations permitting substantial data throughput. Copyright © 2001 John Wiley & Sons, Ltd.
The use of historical materials in elementary science classrooms
Authors: Kafai Yasmin B. , Gilliland‐Swetland Anne J.
Published: August 2002

Science educators have stressed in recent years the importance of providing students with an historical understanding of the development of scientific knowledge. Although many approaches have been suggested for building historical understanding of science, historical source materials have often been deemed too difficult to use with elementary school students. This article reports on a case study that used archival and contemporary source materials in project activities, such as photographs and field notes, to engage students in the processes of data generation, selection, annotation, and evaluation. The curricular science activities of one elementary classroom with 29 fourth and fifth grade students are decribed and analyzed as they build and use archives of historical and contemporary naturalist materials. The article concludes with a discussion of the feasibility and benefits of using historical source materials within elementary science education, as well as the implications for selecting and preparing historical source materials in digital format for use in elementary education. © 2001 John Wiley & Sons, Inc. Sci Ed 85:349–367, 2001.
Image retrieval system for street‐landscape images using adjectives
Authors: Shibata Tatsuya , Kato Toshikazu
Published: August 2002

It has hitherto been difficult to treat landscape images in a database, since their physical characteristics have been described empirically. This paper analyzes the correlation between the physical characteristics (colors, including their brightness, directions, and positions) and their associated adjectives, so that a landscape image can be modeled by using the adjectives. As a result, landscape images can be evaluated automatically, and an unknown landscape image can be retrieved and evaluated. Experiments have been carried out to show the usefulness of the proposed method. © 2001 Scripta Technica, Syst Comp Jpn, 32(6): 62–71, 2001
Information retrieval using conceptual index terms for technical papers in a digital library
Authors: Horii Chinatsu , Imai Masakazu , Chihara Kunihiro
Published: August 2002

In a conventional library the librarian eliminates individual differences in concepts in queries and maintains the reliability of information. In a digital library, however, the goal is to not involve people, and so queries which eliminate precision problems in query results are in demand as a replacement for the librarian. In current retrieval systems, precision is improved by using a hierarchical method such as synonym notation processing. In methods based on word systems, processing to handle the inadequate expression of the intention of a query or the semantic interpretation of a query are insufficient, and information retrieval from a more hierarchical perspective is needed. In this paper the authors propose a retrieval method using a hierarchical perspective based on a system of concepts, and not a retrieval method based on conventional word systems. By adopting the EDR electronic dictionary as a thesaurus and using concept information, queries and words which appear in papers are not processed merely as character strings, but are used in queries with consideration for the meaning of the words. The authors' method can estimate imprecise information in the intentions of queries and the meaning hidden in words, allowing for appropriate query results to be provided to users without the cooperation of a librarian. © 2001 Scripta Technica, Syst Comp Jpn, 32(8): 40–52, 2001
Curvature‐based internal structure analysis of pulmonary nodules using thoracic 3D CT images
Authors: Kawata Yoshiki , Niki Noboru , Ohmatsu Hironobu
Published: August 2002

In qualitative diagnosis for discrimination between malignant and benign pulmonary nodules, the features contributing to the morphologies of existing structures, such as the internal structure and peripheral characteristics of the nodules, pulmonary blood vessels and bronchi become important. In this paper, we will characterize the internal structure of pulmonary nodules in terms of 3D curvature by using thoracic 3D CT images, which present valuable information for qualitative diagnosis, and will describe a technique for distinguishing between benign and malignant nodules. The 3D curvature calculation uses the method of isointensity surfaces, and the image elements of the nodule interior are represented locally by CT values as well as by the shape index and curvedness obtained from the 3D curvature. From these histograms, benign and malignant nodules are globally characterized, allowing their discrimination. Results of screening by physicians, using the pulmonary nodules and the discrimination results obtained by the proposed technique, are compared by using ROC curves and the effectiveness of the proposed technique is shown. © 2001 Scripta Technica, Syst Comp Jpn, 32(11): 9–19, 2001
Fault detection for IC board using histogram of thermography
Authors: Nishino Satoshi , Ohshima Kenji
Published: August 2002

This paper presents a method for fault detection using the standard deviation of the histogram of the thermographic image of an entire board acquired by infrared camera. Another method proposed earlier by the authors requires as many measurements as the IC chips packed on the board; on the other hand, the new method reduces measurement effort by two orders of magnitude while maintaining the same level of accuracy. With this method applied to a high‐density VLSI board, fault detection becomes easier because the variation of the standard deviation in the case of a fault is accelerated by the influence of the faulty IC on neighbor chips and on the entire board. In addition, in terms of the efficiency index defined in terms of the number of measurements and the detection accuracy, the proposed method proves to outperform other techniques, thus offering accurate fault detection with small effort. © 2001 Scripta Technica, Syst Comp Jpn, 32(11): 38–48, 2001
It is not how long it is, but how you make it long – waiting lines in a multi‐step service process
Authors: Fung K. K.
Published: August 2002

Accurate signals are essential to ensure the integrity of the feedback mechanism in systems. But in a multi‐step service process such as a restaurant business, where the flow capacities of the service steps are not identical, visible signals may not indicate the true magnitude to which the system should respond. Specifically, the visible standing queue may not reflect the full length of the waiting line. And if potential customers cannot accurately judge the actual length of the waiting line, varying meal prices to regulate queue length would not be an effective feedback mechanism. Instead, queue length can be more effectively controlled by correctly identifying and widening the most binding bottleneck. Copyright © 2001 John Wiley & Sons, Ltd.
X‐ray photoelectron spectroscopy study of carbon nitride coatings deposited by IR laser ablation in a remote nitrogen plasma atmosphere
Authors: Jama C. , Al khawwam A. , Loir A‐S. , Goudmand P. , Dessaux O. , Gengembre L. , Grimblot J.
Published: August 2002

The reactive pulsed laser deposition technique was used to deposit carbon nitride (CNx) coatings on a silicon substrate. In this process, an infrared transversely excited atmospheric pressure CO2 laser ablation of a graphite target in a remote nitrogen plasma afterglow was used to provide simultaneously both carbon and nitrogen‐containing species. Evidence of different CN bonding configurations has been observed in the deposited coatings. For nitrogen pressures (P) of ≥700 Pa there is an increase in the contribution of sp2 carbon atoms that is associated with graphitization of the CNx coatings. For P increasing from zero to 100 Pa, the comparison between XPS core‐level and valence band spectra of the CNx coatings shows good correlation between the p‐derived states (C 2p electrons) of C–C π bonds in the valence band and the sp2 carbon atom concentration deduced from the C 1s spectra.

The progressive positive contribution of nitrogen lone pair electrons to the valence band is consistent with the increase of the N–C sp3 contribution with P. The decrease in the sp2 carbon atom contribution is associated with the increase of the nitrogen concentration in the coatings. Copyright © 2001 John Wiley & Sons, Ltd.
Summary of ISO/TC 201 Standard: II ISO 14237:2000—Surface chemical analysis—Secondary ion mass spectrometry—Determination of boron atomic concentration in silicon using uniformly doped materials
Authors: Homma Y.
Published: August 2002

This International Standard specifies a secondary ion mass spectrometric method for the determination of boron atomic concentration in single crystalline silicon using uniformly doped materials calibrated by a certified reference material implanted with boron. This method is applicable to uniformly doped boron in the concentration range 1 × 1016–1 × 1020 atoms cm−3. Copyright © 2002 John Wiley & Sons, Ltd.
Individual particle analysis for source apportionment of suspended particulate matter using electron probe microanalysis
Authors: Kim B. A. , Tomiyasu B. , Owari M. , Nihei Y.
Published: August 2002

Suspended particulate matter (SPM) has a complicated system of emission and transport, and a receptor model is required for apportioning the sources of SPM. We have developed a method for individual particle analysis as a method of source apportionment using electron probe microanalysis (EPMA). In this method, elemental analysis of individual SPM particles is carried out using EPMA and the emission source of each is defined according to its x‐ray spectrum. When many particles are analysed, cluster analysis is used to classify particles based on the similarity of elemental composition. If this procedure were automated it could process data more rapidly, with little work required of an analyst. In this study, we examined different kinds of cluster analyses using the data obtained from real SPM samples to increase the reliability of cluster analysis as the method of data analysis for SPM source apportionment. Copyright © 2001 John Wiley & Sons, Ltd.
The design and implementation of the Gecko NFS Web proxy
Authors: Baker Scott , Hartman John H.
Published: August 2002

The World Wide Web uses a naming scheme (URLs), transfer protocol (HTTP), and cache algorithms that are different from traditional network file systems. This makes it impossible for unmodified Unix applications to access the Web; as a result, the Web is only accessible to special Web‐enabled applications. Gecko bridges the gap between Web‐enabled applications and conventional applications, allowing any unmodified Unix application to access the Web. We developed two prototypes of the Gecko system at the University of Arizona and incorporated the many lessons learned from the first into the second. Minimizing the amount of state was a key goal of the Gecko redesign and the second prototype uses a unique compression technique to reduce server state. Experiments performed on the prototype show that Gecko not only makes the Web accessible to unmodified applications, but does so at a performance that meets or exceeds that of HTTP. Copyright © 2001 John Wiley & Sons, Ltd.
Enriching the model‐building phase of soft systems methodology
Authors: Bergvall‐Kåreborn Birgitta
Published: August 2002

Soft Systems Methodology (SSM) has been criticized for its tendency to result in regulatory, rather than radical, agendas for change. It has also been argued that when stressing the difference between different Weltanschauungs SSM takes them at face value and does not investigate the similarities between them or seek an explanation for this in terms of the structure of society. The aim of the paper is to address these critical comments made towards SSM by incorporating a concept called qualifying function as a conceptual tool for modelling and design. The concept has the potential to help people in a particular problem situation to view the situation from new and different perspectives. It also has the potential to enrich the conceptual models by directing the transformation process. Finally, it provides an alternative technique for model validation by relating the root definition and the conceptual model closer together. Copyright © 2001 John Wiley & Sons, Ltd.
Image‐guided breast biopsy
Authors: King Tari A. , Fuhrman George M.
Published: August 2002

Image‐guided breast biopsy has become an attractive alternative to wire‐localized excisional biopsy to evaluate women with nonpalable abnormalities detected by breast imaging. We have organized a database from our institution that includes over 3,500 procedures. We have reviewed our institutional results and the literature pertaining to image‐guided breast biopsy. Discussed in this review are the indications and contraindications for image‐guided biopsy, common techniques employed, accuracy based on pathology, reimbursement issues, and the multidisciplinary approach used at our institution. The results of our review affirm our position that image‐guided breast biopsy is the preferred technique to evaluate women with nonpalpable breast imaging abnormalities. Semin. Surg. Oncol. 20:197–205, 2001. © 2001 Wiley‐Liss, Inc.
A Review of Some Rigorous Software Design and Analysis Tools
Authors: Sheldon Frederick , Xie Gaoyan , Pilskalns Orest , Zhou Zhihe
Published: August 2002

The increasing maturity of formal methods cannot be attributed to only the formal notations and methodologies that are accessible to system designers. The development of powerful software tools that apply and facilitate the use of these notations and methodologies effectively has been crucial. In this paper, FREDERICK SHELDON, GAOYAN XIE, OREST PILSKALNS and ZHIHE ZHOU survey some well‐known software tools that have been deployed and used by both academic and industrial sections for rigorous design and analysis. The software tools are categorized by both the notations and methodologies, upon which they are based. We mainly discuss the tools' underlying formal methods, achievements and scope of applicability. We finish with the future trend of the development of such software tools. Copyright © 2002 John Wiley & Sons, Ltd.
A positron‐emitter labeled glycineB site antagonist, [11C]L‐703,717, preferentially binds to a cerebellar NMDA receptor subtype consisting of GluR ϵ3 subunit in vivo, but not in vitro
Authors: Haradahira Terushi , Okauchi Takashi , Maeda Jun , Zhang Ming‐Rong , Kida Takayo , Kawabe Kouichi , Mishina Masayoshi , Watanabe Yasuyoshi , Suzuki Kazutoshi , Suhara Tetsuya
Published: August 2002

In previous studies, we have found that [11C]L‐703,717, a positron‐emitter labeled antagonist for the glycine‐binding site of NMDA receptors, only localizes in rodent cerebellum under in vivo conditions. In order to understand the unusual cerebellar localization, we have examined the binding of [11C]L‐703,717 to a cerebellar‐specific NMDA receptor subtype consisting of GLuRϵ3 subunit, by comparing its autoradiographic distributions between GluRϵ3‐deficient and wild‐type mice. Ex vivo [11C]L‐703,717 binding to wild‐type mice showed a highly specific localization of radioactivity in the cerebellum, whereas that to the GluRϵ3‐deficient mice showed no specific localization of radioactivity in any of the brain regions. In contrast to the ex vivo binding, in vitro [11C]L‐703,717 binding displayed a similar binding characteristic between GluRϵ3‐deficient and wild‐type mice with highly specific localizations in the hippocampus and cerebral cortex. Therefore, the present study clearly demonstrated that [11C]L‐703,717 preferentially binds to a cerebellar NMDA receptor subtype consisting of GluRϵ3 subunit in vivo, but not in vitro. Synapse 43:131–133, 2002. © 2001 Wiley‐Liss, Inc.
Reciprocal synaptic relationships between angiotensin II‐containing neurons and enkephalinergic neurons in the rat area postrema
Authors: Guan Jian‐Lian , Wang Qing‐Ping , Lu Shuang , Shioda Seiji
Published: August 2002

A preembedding double immunostaining technique was used to study synaptic relationships between angiotensin‐II‐like immunoreactive and enkephalin‐like immunoreactive neurons in the rat area postrema. The angiotensin‐II‐like immunoreactive neurons were detected by silver‐gold intensification of the DAB reaction results while the enkephalin‐like immunoreactive neurons were detected by simple ABC‐DAB reaction. The synaptic relationships were reciprocal between the two neurons. Most of the synapses found between these two neurons were the presynaptic enkephalin‐like immunoreactive axon terminals that made synapses on the angiotensin‐II‐like immunoreactive perikarya and dendrites. Both the axo‐somatic and axo‐dendritic synapses were symmetrical. However, although angiotensin‐II‐like immunoreactive axon terminals also made synapses on enkephalin‐like perikarya and dendrites, the axo‐somatic synapses were symmetrical, while the axo‐dendritic synapses were asymmetrical. The present results confirm the presence of angiotensin‐II‐like immunoreactive neurons in the area postrema and suggest that these angiotensinergic neurons in the area postrema may play a role in the regulation of blood pressure via coordinated synaptic interactions with enkephalinergic neurons. Synapse 41:112–117, 2001. © 2001 Wiley‐Liss, Inc.
Learning and improvement in product innovation processes: Enabling behaviors
Authors: Gieskes Jose F.B. , Langenberg Ilse
Published: August 2002

Product Innovation is described as a continuous and cross‐functional process involving all stages in the product life cycle. This approach gives way to study product innovation processes from a continuous improvement and learning viewpoint. The Continuous Improvement in the global product MAnagement (CIMA) model describes learning and improvement within product innovation processes in terms of a number of interrelated variables: (improvement) performances, behaviors, and levers to stimulate learning and improvement, contingencies, and learning/innovation capabilities. At the Research & Development Department of THOMSON‐CSF SIGNAAL the model was used to assess its current practices with regard to learning and improvement in product innovation processes. The results validate efforts on current and past improvement actions and provide additional insight into the past, current, and future situation. Explicit use of levers that relate to the transfer of knowledge within the product innovation process, such as the formalization and explicit deployment of the emerging strategy, innovation process definition, project planning and control, and human resource management policies, will increase improvement and learning. The recommendations are used to enhance current CMM‐based improvement plans and expand implementation plans. © 2001 John Wiley & Sons, Inc. Syst Eng 4: 134–144, 2001
Probabilistic structural damage assessment and control based on energy approach
Authors: Wong K. K. F. , Wang Y.
Published: August 2002

This paper proposes a probabilistic method for assessing the seismic damage to structures based on both plastic rotation and plastic energy. Four basic features of this method are: (1) the incorporation of the state space method and force analogy method in inelastic dynamic analysis; (2) the exact quantification of the overall plastic energy and individual plastic energy dissipated at each plastic hinge; (3) the definition of damage model with both the monotonic and cyclic damage extremes; and (4) the probabilistic expression of the structural damage indices. An example of a ten‐storey moment‐resisting steel frame is presented to demonstrate the practical application of the proposed procedure. Optimal linear control is applied to improve the structural performance. Responses and energies at selected plastic hinges arising from 28 earthquake ground motions are compared, and statistical characteristic values of these variables are computed. Finally, comparisons are made between the drift ratio and failure probability of the proposed local damage index. Results show that active control can reduce plastic rotation and plastic energy, therefore reducing the damage. In addition, this study shows that using the drift ratio alone is inadequate to predict damage on certain occasions, and the proposed damage index is a more rational measure. Copyright © 2001 John Wiley & Sons, Ltd.
Possible prevention by abieslactone of development of diethylnitrosamine‐initiated GST‐P positive foci in the rat liver
Authors: Iwai Shuji , Wei Min , Morimura Keiichirou , Wanibuchi Hideki , Tanaka Reiko , Matsunaga Shunyo , Yoshitake Akira , Seki Shuichi , Fukushima Shoji
Published: August 2002

Triterpenoid compounds, isolated from plants of Abies genus (Pinceae), are known to exert anti‐tumor promotion activities in mouse skin carcinogenesis. In the present study, we investigated whether AVB‐1 and acid and acid methyl ester derivatives have inhibitory effects on rat hepatocarcinogenesis by using a liver medium‐term bioassay for carcinogens (Ito’s test), immunohistochemically assessing the numbers and areas per cm2 of preneoplastic lesions, glutathione S‐transferase placental form (GST‐P)‐positive foci. In experiment 1, 6‐week‐old male Fisher 344 rats were given a single intraperitoneal injection of diethylnitrosamine (200 mg/kg b.w.) and subjected to two‐thirds partial hepatectomy at week 3. From weeks 2 to 8, the compounds were given three times a week at a dose of 1 mg/kg b.w. by i.g. gavage and found to significantly decrease the number of GST‐P‐positive foci in the liver. In experiment 2, AVB‐1 was given three times a week at doses of 3, 1, or 0.3 mg/kg b.w. by i.g. gavage from weeks 2 to 8. All doses of AVB‐1 significantly decreased the numbers of GST‐P‐positive foci. Thus, our results suggest that AVB‐1 is a chemopreventive agent for rat hepatocarcinogenesis. Teratogenesis Carcinog. Mutagen. 21:223–229, 2001. © 2001 Wiley‐Liss, Inc.
The changing competitive landscape of retail banking in the e‐commerce age
Authors: Wright April
Published: August 2002

The Internet and e‐commerce have changed the competitive landscape of retail banking by eroding the
barriers to entry created by physical branch networks and by increasing the commoditization of banking products and
services. Retail banking was historically the domain of deposit‐taking retail banks, credit unions, and
building societies. These banks now face competition from Internet‐only banks, branded non‐financial
firms, multinationals such as universal bancassurers, and other specialist technology providers. This study
outlines strategies that traditional banks can use to reconfigure their value chains in order to survive in the new
competitive landscape. Strategies include outsourcing Internet technology (IT) functions, forming
alliances with technology providers and competitors, becoming a global player or a product manufacturer, and
focusing on niche markets. © 2002 John Wiley & Sons, Inc.
Using scanning electron microscopy for statistical characterization of the diameter and shape of airborne particles at an urban location
Authors: Franck Ulrich , Herbarth Olf
Published: August 2002

Particles in the air are characterized not only by their effective diameters but by their shapes as well. In this study electron microscopy was used to provide detailed information about individual particles, including diameter and shape. Following image analysis, statistical methods were used to describe diameter and shape distribution. From using this technique for repeated measuring at a particular location an interesting finding was made: the diameter and shape factor distributions had a constant nature. © 2002 Wiley Periodicals, Inc. Environ Toxicol 17: 98–104, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/tox.10037
Assessment of toxicity and mutagenicity in air particulate matter from an urban industrial area in the coast of the Rio de la Plata
Authors: Müller Andrea , Alzuet Pablo , Herbarth Olf , Ronco Alicia
Published: August 2002

Chemical characterization and effects assessment of semivolatile organic compounds in organic extracts from air particulate matter from the region of the greater La Plata area was undertaken. Effects covered the study of mutagenicity with the Ames test (Salmonella typhimurium TA100 and TA98 strains with metabolic activation by S9) and cytotoxicity using the Tetrahymena pyriformis test system (growth rate, cell volume, and cell respiration). Chemical analysis of organic extracts was done using gas chromatography. Results demonstrate the presence of polycyclic aromatic hydrocarbons (PAH) in the matrix, high mutagenicity, and cytotoxicity. A higher mutagenic activity detected with TA98 and TA100 strains is associated with an increment of total PAH and total five or six ring PAH content, respectively. Linked with it, a PAH dependent toxicity on Tetrahymena pyriformis has been observed. This cell system proved to be very sensitive. From the results obtained with the cell respiration assay with T. pyriformis it appears that uncoupling agents are present in the samples. The results of this study indicate that air particulate matter from the Rio de La Plata area contains significant genotoxic and cytotoxic activity probably due to the presence of PAHs. © 2001 John Wiley & Sons, Inc. Environ Toxicol 16: 151–157, 2001
Silica sand as an artificial control sediment in a 20 day Neanthes arenaceodentata toxicity test
Authors: Mcdonald Blair G. , Haynes Patricia A.
Published: August 2002

The use of artificial control sediments in toxicity tests offers several advantages over field‐collected control sediments, especially for laboratory‐cultured organisms such as Neanthes arenaceodentata. Ten side‐by‐side trials were conducted using a field‐collected sediment from West Beach, Whidbey Island, Washington State, USA and an artificial sediment composed of a silica quartz sand commonly used for masonry applications. After a 20‐d exposure to sediment and clean overlying seawater, a similar biological response (as measured by the final average individual dry weight of Neanthes) was observed. The average individual dry weight was 14.77±3.83 and 14.70±3.57 mg/worm for the artificial and field‐collected negative controls, respectively. © 2001 John Wiley & Sons, Inc. Environ Toxicol 16: 172–176, 2001
Tearing Down the Walls: Environmental Performance Improvement in a Maquiladora Facility
Authors: Platkus Walter
Published: August 2002

A pilot project in Tijuana brings together government, industry, and the community to identify and solve
environmental problems. © 2001 John Wiley & Sons, Inc.
Environment as a Core Competency in World‐Class Organizations
Authors: Ferrone Robert
Published: August 2002

Companies need to understand the strategic nature of the environmental management challenge. They must find
ways to create and utilize strategic knowledge faster and more cost‐effectively than their competitors.
© 2001 John Wiley & Sons, Inc.
HAWT dynamic stall response asymmetries under yawed flow conditions
Authors: Schreck S. , Robinson M. , Hand M. , Simms D.
Published: August 2002

Horizontal axis wind turbines can experience significant time‐varying aerodynamic loads, potentially causing adverse effects on structures, mechanical components and power production. As designers attempt lighter and more flexible wind energy machines, greater accuracy and robustness will become even more critical in future aerodynamics models. Aerodynamics modelling advances, in turn, will rely on more thorough comprehension of the three‐dimensional, unsteady, vortical flows that dominate wind turbine blade aerodynamics under high‐load conditions. To experimentally characterize these flows, turbine blade surface pressures were acquired at multiple span locations via the NREL Phase IV Unsteady Aerodynamics Experiment. Surface pressures and associated normal force histories were used to characterize dynamic stall vortex kinematics and normal force amplification. Dynamic stall vortices and normal force amplification were confirmed to occur in response to angle‐of‐attack excursions above the static stall threshold. Stall vortices occupied approximately one‐half of the blade span and persisted for nearly one‐fourth of the blade rotation cycle. Stall vortex convection varied along the blade, resulting in dramatic deformation of the vortex. Presence and deformation of the dynamic stall vortex produced corresponding amplification of normal forces. Analyses revealed consistent alterations to vortex kinematics in response to changes in reduced frequency, span location and yaw error. Finally, vortex structures and kinematics not previously documented for wind turbine blades were isolated. Published in 2000 by John Wiley & Sons, Ltd.
Horizontal axis wind turbine systems: optimization using genetic algorithms
Authors: Diveux T. , Sebastian P. , Bernard D. , Puiggali J. R. , Grandidier J. Y.
Published: August 2002

A method for the optimization of a grid‐connected wind turbine system is presented. The behaviour of the system components is coupled in a non‐linear way, and optimization must take into account technical and economical aspects of the complete system design. The annual electrical energy cost is estimated using a cost model for the wind turbine rotor, nacelle and tower and an energy output model based on the performance envelopes of the power coefficient of the rotor, CP, on the Weibull parameters k and c and on the power law coefficient α of the wind profile. In this study the site is defined with these three parameters and the extreme wind speed Vmax. The model parameters vary within a range of possible values. Other elements of the project (foundation, grid connection, financing cost, etc.) are taken into account through coefficients. The optimal values of the parameters are determined using genetic algorithms, which appear to be efficient for such a problem. These optimal values were found to be very different for a Mediterranean site and a northern European site using our numerical model. Optimal wind turbines at the Mediterranean sites considered in this article have an excellent profitability compared with reference northern European wind turbines. Most of the existing wind turbines appear to be well designed for northern European sites but not for Mediterranean sites. Copyright © 2001 John Wiley & Sons, Ltd.
Fit of EDXRF spectra with a genetic algorithm
Authors: Brunetti Antonio , Golosio Bruno
Published: August 2002

In energy‐dispersive x‐ray fluorescence analysis, the estimation of the net area of the peaks is a primary requirement. This task requires a non‐linear fitting of the peaks. The most common procedures are based on the Marquardt– Levenberg technique. This technique generally works well only when the spectrum is perfectly known, i.e. all the peaks are recognized. Moreover, it is sometimes difficult to introduce constraints on the fit due to peak shape or other physical properties. In this paper a new technique is proposed, based on a set of genetic operators. It works well even when the knowledge of the peaks is incomplete and it also allows one easily to introduce constraints. The results obtained with this algorithm are generally superior with respect to a standard implementation of a Marquardt– Levenberg procedure. The only drawback is the speed of convergence, that is slower than in the Marquardt– Levenberg technique. Copyright © 2001 John Wiley & Sons, Ltd.
Application of J. E. Fernández algorithms in the evaluation of x‐ray intensities measured on fused glass discs for a set of international standards and a proposed calibration procedure
Authors: Malmqvist J.
Published: August 2002

J. E. Fernández algorithms, based on a solution of the Boltzmann transport equation describing the transport of photons in a specimen, are assembled in a computer program, MSXRF. The algorithms include different treatments of single and double photon collisions undergoing photoelectric, Rayleigh and/or Compton interactions, polarization effects and Compton broadening. The MSXRF program has been linked to another computer program, TNPP, governing input and output data, calibration parameters, choice of main elements etc.

A slightly different approach to a calibration procedure is proposed, which makes use of the hybrid MSXRF‐TNPP program. This lining‐up procedure is based on measurement of a pure calibration standard and is a ‘one‐point’ determination of the analytical curve. The model is examined and adjusted by using a set of international standards covering a range from ppm levels to the highest concentrations. The same international standards are also used to control and describe the performance characteristics of the analytical method. The new calibration procedure is simpler in comparison with the earlier used.

Analytical results, evaluated by the MSXRF‐TNPP program of measured CRM standards, have been compared with results from an earlier investigation, evaluated by the TNPP program only. The latter program is cruder in its design with regards to existing theories and setting of parameters and is not applicable over large concentration ranges without using correction factors for scattering and other specific effects. The results achieved were comparable to those from the production TNPP program.

Problems such as the processing time, which is of utmost importance when applying a program in practice, is discussed. Today the evaluation time is unacceptable but an execution time of only a few minutes is reckoned to be good with new strategies. Copyright © 2001 John Wiley & Sons, Ltd.
Method for the calculation of the chemical composition of a thin film by Monte Carlo simulation and electron probe microanalysis
Authors: Hu Youhua , Pan Yinrong
Published: August 2002

Based on a simplified Monte Carlo simulation model of electron scattering and characteristic x‐ray excitation of a multicomponent film on a substrate, a calculation method with an iteration approach was developed to transform the x‐ray intensity ratios measured by an electron probe microanalyzer into the chemical composition of the thin film on the substrate. The calculation of the characteristic fluorescence is also included in the simulation. The calculation results of compositions for several specimens agree well with measured data. Copyright © 2001 John Wiley & Sons, Ltd.
Multielemental x‐ray fluorescence analysis by using a non‐explicit description of the excitation beam
Authors: Barrea R. A. , Martínez V. Delgado , Plivelic T. S.
Published: August 2002

The fundamental parameters method has been extensively used for XRF analysis applications. One of the method's requirements is an explicit knowledge of the excitation beam used, which is not always available. Recently, a methodology that avoids the direct reconstruction of the x‐ray beam using a non‐explicit representation was published. In this paper the results of a multicomponent analysis of stainless‐steel samples with this methodology are presented. The concentrations obtained were compared with NBS certified values and very good agreement was found. Two parameteric models of beam description were also used in order to compare the goodness of each spectral representation (the non‐explicit model and the parametric ones) to perform x‐ray fluorescence analysis. The proposed methodology showed better results, in terms of accuracy and precision, than the standard methodology, in the case of a continuous spectrum of the exciting beam. When the spectrum of the exciting beam exhibits discontinuities (i.e. absorption edges and characteristic lines), the results of the three descriptions are comparable. It was demonstrated that the fundamental parameters method without an explicit knowledge of the excitation beam is suitable for use in x‐ray fluorescence analysis. Copyright © 2001 John Wiley & Sons, Ltd.
Theoretical model for the calculation of interference effects in TXRF and GEXRF
Authors: Pérez Roberto Daniel , Sánchez Héctor Jorge , Rubio Marcelo
Published: August 2002

Interference effects between the contributions of transmitted and reflected radiation are observed during x‐ray propagation at grazing angles in stratified media. This phenomenon affects the fluorescence intensity in grazing incidence experiments [total reflection x‐ray fluorescence (TXRF)] and grazing emission experiments [grazing emission x‐ray fluorescence (GEXRF)], thus producing a characteristic interference pattern in the fluorescence spectra. The theoretical description of this effect can be studied by using models based on the general problem of an electromagnetic wave propagating through a stratified medium. In this work, a new approach to this problem is presented based on the development of approximations in the electric field. This approach uses a new theoretical formalism introduced recently. By using this new model, we proved that in order to evaluate the interference effects of an electric field in any surface layer, the influence of the surface layers over the layer analyzed can be neglected. By using this result, the precision obtained in the calculations of an electric field is acceptable. As an example, we present theoretical calculations for x‐ray propagation at glancing angles in testing stratified structures. The usual theoretical models for data analysis of TXRF and GEXRF experiments can be simplified by applying the present model. Furthermore, our results allow a better understanding of the experimental data obtained with both techniques. Copyright © 2001 John Wiley & Sons, Ltd.