bluuebunny/crossref_metadata_2025 huggingface dataset:
Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry and high‐performance liquid chromatography study of quantitative and qualitative variation in tarantula spider venoms
Authors: Escoubas Pierre , Corzo Gerardo , Whiteley Brian J. , Célérier Marie‐Louise , Nakajima Terumi
Published: September 2002

Animal venoms are important sources of novel pharmacological tools, useful in biochemical characterization of their receptors. Venom quality control, batch‐to‐batch homogeneity and high reproducibility of venom fractionation and toxin purification are crucial issues for biochemical and pharmacological studies. To address these issues, a study of the variability of tarantula spider venom samples was undertaken. Venom profiles of samples collected from individuals of different age and sex, and from sibling spiders of the same species, were generated by high‐performance liquid chromatography (HPLC) and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) and analyzed to assess venom variability and method accuracy. Sex‐linked venom variation was studied on eight species. Clear qualitative differences were observed for six out of eight species, as well as quantitative differences. Age‐related variation studied in Poecilotheria rufilata showed essentially age‐related quantitative differences between adults of both sexes and immature juveniles. The venoms of nine siblings and three wild‐collected Pterinochilus murinus were studied for individual variation, showing only very minor quantitative differences. On the same samples, the quality of MALDI‐TOFMS venom fingerprinting was demonstrated to be highly reproducible. Our results show that tarantula venom peptide fingerprinting is a highly reliable identification method, that pooled batches of venom from several animals can be used for venom purification, that venom composition does not appear to be qualitatively related to ontogenesis in the spiders studied, and that qualitative sex‐linked variation occurs across most species and may be important in activity studies. Copyright © 2002 John Wiley & Sons, Ltd.
Measurements by gas chromatography/pyrolysis/mass spectrometry: fundamental conditions in 2H/1H isotope ratio analysis
Authors: Bilke Steffi , Mosandl Armin
Published: September 2002

Gas chromatography/pyrolysis/isotope ratio mass spectrometry (GC/P/IRMS) is a relatively new method for on‐line determination of 2H/1H isotope ratios. The influence of different parameters on the 2H/1H isotope ratios obtained in GC/P/IRMS has been thoroughly studied using several flavor compounds, such as 5‐nonanone, linalool, menthol, linalyl acetate and 4‐decanolide. The requirement of ‘conditioning’ the pyrolysis reactor to obtain reliable δ2HV−SMOW values is discussed. Furthermore, the influence of the carrier gas flow of the gas chromatograph on the completeness of pyrolysis and subsequently on the δ2HV−SMOW values is investigated in detail. The linear range of the compounds investigated is determined. The results show that calibrating the GC/P/IRMS system with secondary standard substances is absolutely necessary in order to obtain reliable δ2HV−SMOW values. In view of interlaboratory comparability, validation procedures are recommended. Copyright © 2002 John Wiley & Sons, Ltd.
Identification of omega hydroxy fatty acids in biological samples as their pentafluoropropyl derivatives by gas chromatography/mass spectrometry with positive and negative ion detection
Authors: Zemaitis Michael , Poloyac Samuel , Frye Reginald
Published: September 2002

A simple one‐step procedure for derivatization of the omega hydroxy fatty acids 20‐hydroxyeico‐tetraeonic acid and 12‐hydroxylauric acid is presented. The procedure involves acylation of the terminal hydroxy group and esterification of the carboxylic acid with a mixture of pentafluoropropionic anhydride and pentafluoropropanol. Positive and negative ion spectra for the derivatives are presented. The procedure was used to demonstrate conversion of arachidonic acid to 20‐hydroxyeicosatetraeonic acid and lauric acid to 12‐hydroxylauric acid in kidney microsomal incubations. The reaction appears to be specific, since derivatives of subterminal fatty acids (secondary alcohols) could not be detected. Copyright © 2002 John Wiley & Sons, Ltd.
Quantitative analysis of diclazuril in animal plasma by liquid chromatography/electrospray ionization mass spectrometry
Authors: Croubels Siska , Cherlet Marc , Backer Patrick De
Published: September 2002

A novel, sensitive and specific method for the quantitative determination of diclazuril in animal plasma using liquid chromatography combined with electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) with negative ion detection is presented. Extraction of the samples was performed with a rapid deproteinization step using acetonitrile. Chromatography of diclazuril and the internal standard was achieved on a Nucleosil ODS 5‐µm column, using a gradient elution with 0.01 M ammonium acetate and acetonitrile. To obtain the highest sensitivity and specificity possible, the mass spectrometer was operated in the multiple reaction monitoring (MRM) mode. The method was validated according to the requirements defined by the European Community. Calibration curves using plasma fortified between 1–100 ng/mL and 100–2000 ng/mL showed good linear correlation (r ≥ 0.9991, goodness‐of‐fit coefficient ≤7.0%). The trueness and within‐run precision at 50 and 500 ng/mL did not exceed 8.8 and 10.5%, respectively. The between‐run precision for the analysis of quality control samples at 50 and 1000 ng/mL was within 11.7%. The most striking advantage of the proposed method was the high sensitivity and specificity achieved. A limit of quantification of 1 ng/mL was obtained, for which the trueness and precision also fell within acceptable limits. Using a signal‐to‐noise ratio of 3:1, the limit of detection was calculated to be 0.03 ng/mL. The method has been successfully used for the quantitative determination of diclazuril in plasma samples from treated sheep, demonstrating the usefulness of the developed method for application in the field of pharmacology and pharmacokinetics. Copyright © 2002 John Wiley & Sons, Ltd.
New example of proline‐induced fragmentation in electrospray ionization mass spectrometry of peptides
Authors: Maux Delphine , Enjalbal Christine , Martinez Jean , Aubagnac Jean‐Louis
Published: September 2002

The positive ion electrospray ionization (ESI+) mass spectra of peptides usually display only protonated molecules provided that soft ionization conditions are applied (low cone voltage to prevent in‐source dissociations). Such ions can be multiply charged depending on the molecular weight of the studied compounds. We have experienced an unexpected behavior during the ESI analysis of a modified peptide of relatively high mass (3079 Da). A specific fragmentation occurred even under soft energetic conditions, leading to a mass spectrum containing multiply charged molecular and fragment ions. The selective rupture involved the amide bond between the glutamic acid and proline residues (E‐P sequence). The successive replacement of each amino acid by an alanine residue (positional scanning study) was undertaken to assess which part of the sequence induced such selective and abundant fragmentation on multiply charged species. The succession P‐P was evidenced as the minimum unit giving rise to the first peptide bond rupture in the sequence X‐P‐P. Any acidic amino acid at the X position (X = D, E) favored the fragmentation by an intramolecular interaction. Such proline‐induced fragmentation occurring readily in the source differed from the literature data on the specific behavior of proline‐containing peptides where bond ruptures occur solely in dissociation conditions. Copyright © 2002 John Wiley & Sons, Ltd.
Control of a thrust‐vectored flying wing: a receding horizon—LPV approach
Authors: Jadbabaie Ali , Hauser John
Published: September 2002

This paper deals with the application of receding horizon methods to hover and forward flight models of an experimental tethered flying wing developed at Caltech. The dynamics of the system are representative of a vertical landing and take off aircraft, such as a Harrier around hover, or a thrust‐vectored aircraft such as F18‐HARV or X‐31 in forward flight. The adopted control methodology is a hybrid of receding horizon techniques and control Lyapunov function (CLF)‐based ideas.

First, a CLF is generated using quasi‐LPV methods and then, by using the CLF as the terminal cost in the receding horizon optimization, stability is guaranteed. The main advantage of this approach is that stability can be guaranteed without imposing constraints in the on‐line optimization, allowing the problem to be solved in a more efficient manner. Models of the experimental set‐up are obtained for the hover and forward flight modes. Numerical simulations for different time horizons are presented to illustrate the effectiveness of the discussed methods. Specifically, it is shown that a mere upper bound on the cost‐to‐go is not an appropriate choice for a terminal cost, when the horizon length is short. Simulation results are presented using experimentally verified model parameters. Copyright © 2002 John Wiley & Sons, Ltd.
Numerical direct kinematic analysis of fully parallel linearly actuated platform type manipulators
Authors: Wang Li‐Chun T. , Oen Ka‐Tjun
Published: September 2002

This article presents a new numerical approach for solving the direct kinematics problem of fully parallel, linearly actuated platform manipulators. The solution procedure consists of two stages. The first stage transforms the direct kinematics problem into an equivalent nonlinear programming program, and a robust search algorithm is developed to bring the moving platform from arbitrary initial approximation to a feasible configuration that is near to the true solution. The second stage uses the Newton‐Raphson iterative method to converge the solution to the desired accuracy. This approach is numerically stable and computationally efficient. In addition, by randomly perturbing the initial approximations, it can be implemented successively to find multiple solutions to the direct kinematics problem. Two numerical examples are presented to demonstrate the stability and efficiency of this approach. © 2002 Wiley Periodicals, Inc.
Phase transition for Parking blocks, Brownian excursion and coalescence
Authors: Chassaing P. , Louchard G.
Published: September 2002

In this paper, we consider hashing with linear probing for a hashing table with m places, n items (n < m), and ℓ = m − n empty places. For a noncomputer science‐minded reader, we shall use the metaphore of n cars parking on m places: each car ci chooses a place pi at random, and if pi is occupied, ci tries successively pi + 1, pi + 2, until it finds an empty place. Pittel [42] proves that when ℓ/m goes to some positive limit β < 1, the size B of the largest block of consecutive cars satisfies 2(β − 1 − log β)B = 2 log m − 3 log log m + Ξm, where Ξm converges weakly to an extreme‐value distribution. In this paper we examine at which level for n a phase transition occurs between B = o(m) and m − B = o(m). The intermediate case reveals an interesting behavior of sizes of blocks, related to the standard additive coalescent in the same way as the sizes of connected components of the random graph are related to the multiplicative coalescent. © 2002 Wiley Periodicals, Inc. Random Struct. Alg., 21: 76–119, 2002
The diameter of a long‐range percolation graph
Authors: Coppersmith Don , Gamarnik David , Sviridenko Maxim
Published: September 2002

We consider the following long‐range percolation model: an undirected graph with the node set {0, 1, … , N}d, has edges (x, y) selected with probability ≈ β/∥x − y∥s if ∥x − y∥ > 1, and with probability 1 if ∥x − y∥ = 1, for some parameters β, s > 0. This model was introduced by Benjamini and Berger [2], who obtained bounds on the diameter of this graph for the one‐dimensional case d = 1 and for various values of s, but left cases s = 1, 2 open. We show that, with high probability, the diameter of this graph is Θ(log N/log log N) when s = d, and, for some constants 0 < η1 < η2 < 1, it is at most N when s = 2d, and is at least N when d = 1, s = 2, β < 1 or when s > 2d. We also provide a simple proof that the diameter is at most logO(1) N with high probability, when d < s < 2d, established previously in [2]. © 2002 Wiley Periodicals, Inc. Random Struct. Alg., 21: 1–13, 2002
Support system for user interests expression on searching web pages
Authors: Sunayama Wataru , Nomura Yuji , Ohsawa Yukio , Yachida Masahiko
Published: September 2002

An Internet user who wants to know about a certain topic uses a search engine to find pages related to that topic. However, there are so many pages on the World Wide Web that the user cannot access the pages directly, because most search engines output URLs matching the exact words entered by the user. In addition, even though users use intelligent search techniques, it is difficult to input proper keywords because of lack knowledge or lapse of memory. This paper presents a Support System for User Interest Expression which supplies users with keywords, combining the user's interests with information on the WWW, making it possible to input search keywords concretely and precisely. © 2001 Scripta Technica, Syst Comp Jpn, 32(13): 14–22, 2001
A dynamic synchronization protocol and scheduling method based on Timestamp Ordering for real‐time transactions
Authors: Adaka Masanori , Okubo Eiji
Published: September 2002

In this article, we propose a dynamic synchronization protocol and a scheduling method based on Timestamp Ordering for real‐time transactions. First, we describe a synchronization protocol that avoids transaction abort by reserving shared resources accessed by transactions. This protocol does not incur unnecessary wait for resources, so it shows excellent performance under time constraint, compared with the priority ceiling protocol used in static scheduling environment. Next, we describe a dynamic scheduling method that takes into account both Timestamp Ordering and priority of transactions. This method does not incur deadlock unlike two‐phase locking, for example, and it can decrease violation of time constraint due to resource waiting. We compare the two proposed methods and other methods by simulation, and discuss the effectiveness of the proposed methods. © 2001 Scripta Technica, Syst Comp Jpn, 32(13): 61–70, 2001
A feature of 2D and 3D images invariant to similarity transformations based on the bispectrum
Authors: Horikawa Yo
Published: September 2002

A novel feature of 2D and 3D patterns invariant to similarity transformations is derived from the bispectrum. The invariant feature is a histogram of triple products of frequency components and is calculated with the Fourier transform of original images. Computer experiments on sinusoidal patterns, 2D texture images, and 3D brain images show that the invariant feature is applicable to the classification of images shifted and rotated arbitrarily, scaled up to double size, and including additive noise up to 0 dB. © 2002 Scripta Technica, Syst Comp Jpn, 33(3): 1–10, 2002
Real‐time production system shell supporting persistent data
Authors: Nishiyama Satoshi , Ono Chihiro , Obana Sadao , Suzuki Kenji
Published: September 2002

The implementation and evaluation of a production system shell which can negotiate a large amount of data over a database and is capable of responding in real time to external changes such as alarms, from networks is discussed with the goal of applying it to expert systems in such fields as network management. The matching algorithm is obtained by extending the LEAPS matching algorithm, based on the highest priority search, by incorporating external changes into it in real time. In addition, data are stored persistently in a database and such persistent data can be used for inference by differentiating them from the nonpersistent data of the main memory. The evaluation results showed that external changes can be reflected in inference in real time, that inference with respect to the persistent data can be realized with a performance 1/10 to 1/50 of that in the case of nonpersistent data by matching, and that it is possible to achieve high‐speed processing, several times to several tens of times as fast as past inference methods which store data in widely used database management systems (DBMS) and perform inference by accessing the data by SQL and the like from the expert system. © 2002 Scripta Technica, Syst Comp Jpn, 33(3): 11–20, 2002
Evaluation of a data preload mechanism for a linked list structure
Authors: Yamamura Shuji , Kadota Tadafumi , Hirata Hiroaki , Niimi Haruo , Shibayama Kiyoshi
Published: September 2002

The authors have been developing a data preload/prefetch scheme for a linked list structure. In this paper, results of evaluating this preload scheme with benchmark programs requiring frequent pointer operations are reported. This scheme is characterized by the fact that the pointer value of a linked list is preloaded and stored, and a mechanism of providing the pointer value without delay for subsequent instructions is installed inside the processor. While dramatic performance improvement is expected by preloading/prefetching of a pointer value in this scheme, it is feared that a speculative execution using a preloaded pointer value before an update may fail if the linked list structure is modified, which may influence the performance negatively. However, it has been confirmed that in actual programs, such a failure of speculative execution does not occur, so that no performance problem arises. The evaluation results have confirmed a maximum performance improvement of 24.3% and the efficacy of the scheme. © 2002 Scripta Technica, Syst Comp Jpn, 33(3): 21–30, 2002
Styling and animating human hair
Authors: Kishi Keisuke , Morishima Shigeo
Published: September 2002

Synthesizing facial images by computer graphics (CG) has attracted attention in connection with the current trends toward synthesizing virtual faces and realizing communication systems in cyberspace. In this paper, a method for representing human hair, which is known to be difficult to synthesize in computer graphics, is presented. In spite of the fact that hair is visually important in human facial imaging, it has frequently been replaced by simple curved surfaces or a part of the background. Although the methods of representing hair by mapping techniques have achieved results, such methods are inappropriate in representing motions of hair. Thus, spatial curves are used to represent hair, without using textures or polygons. In addition, hair style design is simplified by modeling hair in units of tufts, which are partially concentrated areas of hair. This paper describes the collision decisions and motion representations in this new hair style design system, the modeling of tufts, the rendering method, and the four‐branch (quadtree) method. In addition, hair design using this hair style design system and the animation of wind‐blown hair are illustrated. © 2002 Scripta Technica, Syst Comp Jpn, 33(3): 31–40, 2002
Response of a pacemaker neuron model to transient pulse trains
Authors: Yamanobe Takanobu , Nomura Taishin , Pakdaman Khashayar , Sato Shunsuke
Published: September 2002

In this study, the response of the pacemaker neuron model to transient pulse inputs (input sequence composed of a finite number of pulses with interval variations) is examined. The shift of the firing phase of the pacemaker neuron generated by a single pulse stimulus is represented by the phase transition curve. The dynamics of the pacemaker neuron receiving pacemaker pulse stimuli has been analyzed in terms of the one‐dimensional discrete dynamical system derived from the phase transition curve. This paper shows that the dynamics of the model for the transient pulse input can be described by a finite set of phase transition curves. The constructed pacemaker neuron model can reproduce the response of the slowly adapting stretch receptor organ (SAO) of the crayfish to the transient pulse inputs observed in the experiment. It is observed in the experiment that the qualitative property of the response pattern of the SAO to the transient pulse inputs changes suddenly while the input is applied. In order to analyze the generation mechanism underlying the response to the transient pulse inputs, the response of the model is analyzed in detail for inputs with increasing rate, that is, pulse input trains in which the inverse of the input pulse interval monotonically increases. In particular, the mechanism of generation of the paradoxical response, in which the output rate increases monotonously in response to the inhibitory input with increasing rate, is described. © 2002 Scripta Technica, Syst Comp Jpn, 33(3): 63–73, 2002
Meshing technology with quality assurance for curved surfaces defined by linear Lie algebra
Authors: Kawano Shin‐ichi , Makino Mitsunori , Ishii Shinya , Chao Jinhui
Published: September 2002

A high‐quality triangular meshing is proposed for surfaces defined by linear Lie algebra. It is known that linear Lie algebra can define a variety of surfaces including a certain type of nonalgebraic surfaces as well as algebraic ones. Therefore, it is also applicable to the field of computer vision. However, in a case of visualizing efficiently such surfaces by computer graphics, an adaptive approximation of the surfaces is necessary. In this paper, by considering fluctuation of the normal vector in the neighborhood of an obtained point on the surface, an adaptive meshing algorithm is presented, which holds high‐quality approximation of the object. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(10): 64–73, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1158
Using infrared‐transparent pigments to identify objects
Authors: Yamamiya Shirou , Makino Hideo , Hirono Mikihiko , Maeda Yoshinobu , Ishii Ikuo
Published: September 2002

With the goal of developing an invisible code that can be used to identify objects, we have created several pigments for color printing that share the characteristic of being transparent to near‐infrared light, along with methods to print them. Our recent research has emphasized applications as we continue to pursue our investigations of the characteristics of these infrared‐transparent pigments. In the course of our studies, we have discovered a black pigment with high transparency in the infrared (AM‐BK) (Makino, Yamamiya, and colleagues, 1997). This pigment has visible light characteristics that are the same to the naked eye as ordinary pigments, and like these pigments it is “lightfast,” that is, resistant to bleaching by light. For this reason, we anticipate that there will be applications for AM‐BK in the so‐called “universal design” area, whose goals are to provide information to visually impaired people, to keep track of lost or disoriented elderly people noninvasively, and so on. With this in mind, we have recently attempted to create pigments with colors other than black, and to increase the information density they can encode, so as to extend the range of uses for such pigments. In this article, we describe the optical characteristics of the pigments we have developed, and our efforts to use them in a specific type of invisible code. The inks we used in our code experiments generally were of two types: inks that incorporate carbon black (CB), which absorbs infrared light, and inks that contain AM‐BK pigment, which is transparent to infrared light. By mixing these two varieties of inks with solid‐color pigments, we were able to make pigments in three visible‐light colors—yellow, red, and blue. In an experiment with applications in mind, we then screen‐printed a bright yellow lattice‐like floral pattern on a T‐shirt with a “marker” for identifying an individual—the numbers [911]—hidden in it. Our results confirmed that when these numbers were concealed in the T‐shirt pattern by printing them with the above‐mentioned IR‐transparent pigments AM‐BK and CB, a CCD camera was able to distinguish them with ease although they were invisible to the naked eye. These experiments also revealed that as the amount of CB added to the pigment increases, its transparency to near‐infrared light falls off exponentially. This shows that it is possible to create gray‐scale contrasts, which could be used to encode high‐density two‐dimensional bar codes. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(10): 74–82, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1159
Floodplains and Agenda 21: the Upper Nene Valley Project
Authors: Kwolek A. V. A. , Jackson J. I.
Published: September 2002

There is a growing awareness of how floodplain habitats contribute to global biodiversity and of the benefits of undrained floodplain ecosystems, for example: floodwater storage and improvement of water quality. Yet floodplain habitats in Britain are much diminished, with a recent survey showing only 4.2% of lowland river sites, with adjacent floodplain, had extensive wetlands remaining. This Agenda 21 pilot project addresses issues raised by local communities in six parishes along the Upper Nene Valley, in Northamptonshire. These include intensive agriculture, biodiversity conservation, recent serious flooding, gravel extraction and the pressure for housing developments. The project aims to increase the local community's environmental awareness, develop links with farmers and businesses and provide a valuable input to planning policies. Partners include the parish councils and residents within the project area, South Northamptonshire Council and University College Northampton. This paper describes the project vision and initial steps taken to involve local communities in ecological and archaeological surveys. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
Developing sustainability: environmental non‐governmental organizations in former Soviet Central Asia
Authors: Farmer Andrew M. , Farmer Alma A.
Published: September 2002

Former Soviet Central Asia has inherited severe environmental problems from the Soviet Union, alongside a range of social and political structures and poor economic performance. Subsequent political developments have been highly varied, ranging from the development of relatively open societies to highly authoritarian. A large number of environmental NGOs have been formed in all five republics, some from the Soviet period, but mostly in the independent republics. These have received some support from western institutions. However, while they are successful in undertaking a range of activities, they are often fragmented and have short‐term planning and limited impacts of governments. Environmental NGO activity is complicated by the presence of ‘quasi’‐NGOs with official government support and, in some cases, by the direct participation of NGOs in election processes. Environmental NGOs play an important role in developing a more sustainable society in Central Asia, not least in promoting the concepts of civil society. However, their future development should not necessarily be viewed within western models of NGOs. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
Social equity in housing in the Hong Kong Special Administrative Region: a social sustainability perspective
Authors: Chiu Rebecca L. H.
Published: September 2002

The housing arena in Hong Kong has undergone dramatic transformation due to the change in government in 1997 and the subsequent economic recession engendered by the Asian financial crisis. This paper applies the sustainable development perspective to investigate whether policy changes and government responses to the collapse in the property market have made the distribution and consumption of Hong Kong more equitable. It argues that the government's emphasis on home ownership has intensified horizontal and vertical inequity but that the economic recession has the unintended effect of reducing vertical inequity between the low‐ and the lower‐middle‐income groups. Simultaneously, the recession has reduced the housing choices and mobility of the middle‐income groups, rendering them the real losers of the housing policies and economic changes after 1997. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment.
Property‐led urban renewal in Hong Kong: any place for the community?
Authors: Ng Mee Kam
Published: September 2002

The community plays a very limited role in urban governance in pro‐growth Hong Kong. Urban renewal is a case in point. The government has relied on market forces in renewing the city. In 1988, the Land Development Corporation (LDC) was set up to facilitate private–public partnerships in redevelopment. Residents were not involved until the project implementation stage, when owners needed to be compensated and tenants rehoused. However, the growing stock of dilapidated buildings, coupled with the collapse of the property market in the late 1990s, contributed to a market failure. The Urban Renewal Authority (URA) was set up in 2000 to replace the LDC and an Urban Renewal Strategy (URS) was published in 2001. This paper argues that the URS is just a redevelopment programme and that it is doubtful whether the URA can overcome problems faced by the LDC. An integrated approach is advocated to tackle urban restructuring, with active involvement from the community. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment.
Social justice, equity and housing: a new agenda for Scotland?
Authors: McCarthy John , Edgar Bill
Published: September 2002

The formulation and delivery of housing policy in Scotland has undergone significant change in recent years, due in large part to the momentum for change brought about by the creation of the Scottish Parliament and the Scottish Executive in 1999. This paper sets out the context to the parliament's approach to housing policy and the broader historical context to housing and regeneration policy in Scotland. It then focuses on the effects of these contextual changes in terms of the substance of the Housing (Scotland) Act 2001 and the creation of a new executive housing and community regeneration agency—Communities Scotland. Finally, it speculates on the longer‐term implications of these institutional and policy innovations with respect to broader issues of social justice and equity in Scotland. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment.
Dana Meadows: thinking globally, acting locally
Authors: Sterman John D.
Published: September 2002

This article introduces the special issue of System Dynamics Review dedicated to the memory of Dana Meadows. It reviews her role as a leader in the fields of environmental journalism, system dynamics, and systems analysis, and summarizes the articles in the special issue. Copyright © 2002 John Wiley & Sons, Ltd.
Correcting for non‐compliance of repeated binary outcomes in randomized clinical trials: randomized analysis approach
Authors: Matsuyama Yutaka
Published: September 2002

We develop the randomized analysis for repeated binary outcomes with non‐compliance. A break randomization‐based semi‐parametric estimation procedure for both the causal risk difference and the causal risk ratio is proposed for repeated binary data. Although we assume the simple structural models for potential outcomes, we choose to avoid making any assumptions about comparability beyond those implied by randomization at time zero. The proposed methods can incorporate non‐compliance information, while preserving the validity of the test of the null hypothesis, and even in the presence of non‐random non‐compliance can give the estimate of the causal effect that treatment would have if all individuals complied with their assigned treatment. The methods are applied to data from a randomized clinical trial for reduction of febrile neutropenia events among acute myeloid leukaemia patients, in which a prophylactic use of macrophage colony‐stimulating factor (M‐CSF) was compared to placebo during the courses of intensive chemotherapies. Copyright © 2002 John Wiley & Sons, Ltd.
Estimating efficacy in clinical trials with clustered binary responses
Authors: Albert Jeffrey M.
Published: September 2002

When non‐compliance occurs in a clinical trial, it may be of interest to supplement the intent‐to‐treat analysis with an analysis of the efficacy (or biological effect) of therapy. Sommer and Zeger (1991) developed a method for estimating efficacy applicable to the case of a binary response variable and all‐or‐none compliance that assumes independent subject responses. We extend this approach to accommodate within‐cluster correlations as may be expected in a cluster‐randomized design. The method is illustrated using data from a controlled village‐randomized clinical trial conducted in Indonesia to investigate the effect of vitamin A supplementation on mortality in children. We find that within‐cluster correlations for these data are very small and that taking into account the clustering does not substantially affect inferences in this case. Additional calculations show that small within‐cluster correlations (though larger than those found in the vitamin A data) may have a large impact on efficacy inferences. We also present the results of a simulation study that demonstrates the validness of the proposed approach for finite sample sizes. Copyright © 2002 John Wiley & Sons, Ltd.
Estimation of the survival function for Gray's piecewise‐constant time‐varying coefficients model
Authors: Valenta Zdenek , Weissfeld Lisa
Published: September 2002

Gray's extension of Cox's proportional hazards (PH) model for right‐censored survival data allows for a departure from the PH assumption via introduction of time‐varying regression coefficients (TVC). For this model estimation of the conditional hazard rate relies on the inclusion of penalized splines. Cubic penalized splines tend to be unstable in the right tail of the distribution and thus quadratic, linear and piecewise‐constant penalized splines may be a favourable choice. We derive a survival function estimator for one important member of the class of TVC models – a piecewise‐constant time‐varying coefficients (PC‐TVC) model. Using the first‐order Taylor series approximation we also derive an estimate for the variance of the log‐transformed and log(‐log)‐transformed survival function, which in turn leads to estimated confidence limits on the corresponding scales of the survival function. Accuracy in estimating underlying survival times and survival quantiles is assessed for both Cox's and Gray's PC‐TVC model using a simulation study featuring scenarios violating the PH assumption. Finally, an example of the estimated survival functions and the corresponding confidence limits derived from Cox's PH and Gray's PC‐TVC model, respectively, is presented for a liver transplant data set. Copyright © 2002 John Wiley & Sons, Ltd.
Traumatic stress and coping strategies of sesternary victims following an aircraft disaster in Coventry
Authors: Chung Man Cheung , Easthope Yvette , Chung Catherine , Clark‐Carter David
Published: September 2002

In December 1994, an aircraft was returning to Coventry, UK after unloading a cargo of live animals in Amsterdam. The aircraft struck a pylon, subsequently lost control, and started to descend on a large complex of housing estates. It clipped the roofs of two houses and finally crashed into a woodland area close to the edge of a large housing estate. Hundreds of residents on the housing estate had escaped death and were classified as sesternary victims, in that, but by chance, they would have been primary victims. The aims of the study were to examine the traumatic stress of the sesternary victims and the coping strategies that they employed in order to cope with the effects of the trauma. The hypothesis was that the victims would exhibit traumatic distress associated with a specific model of coping characterized by distancing, escape–avoidance, and seeking social support. Eighty‐two victims participated in the study and were interviewed using the Impact of Event Scale (IES), the General Health Questionnaire (GHQ) and the Ways of Coping Checklist (WOC). The results showed that the victims experienced more intrusion than avoidance, and that there were no significant differences between the present samples and standardized samples. Fifty‐six per cent scored above the cutoff point of 4 in the GHQ. Confrontive coping, distancing, self‐controlling, accepting responsibility, escape–avoidance, and positive reappraisal were used by the victims significantly more than the standardized samples. Path analyses showed that avoidance was predicted by the escape–avoidance coping strategy, that intrusion was predicted by distancing and escape–avoidance strategies and that the GHQ total was predicted by distancing and escape–avoidance coping strategies. The conclusion was that the victims exhibited significant traumatic distress which was partially associated with the specific model of coping that we hypothesized. Seeking social support did not seem to account for distress. Copyright © 2001 John Wiley & Sons, Ltd.
How hospital consultants cope with stress at work: implications for their mental health
Authors: Graham Jill , Albery Ian P. , Ramirez Amanda J. , Richards Michael A.
Published: September 2002

Aims. This study examined the ways in which hospital consultants commonly cope with stress at work, and the relationships of these behaviours with their mental health.

Methods. Eight hundred and eighty‐two consultants returned a postal questionnaire asking them how frequently they used various behaviours in response to stress at work. The prevalence of psychiatric morbidity was estimated using the 12‐item General Health Questionnaire.

Findings. Hospital consultants who maintained a balanced, healthy lifestyle while experiencing stress at work were approximately half as likely as those who did not to have psychiatric morbidity [odds ratio 0.44 (0.31–0.61)]. Consultants who used alcohol or non‐prescription drugs in response to stress at work were more than twice as likely as those who did not to have psychiatric morbidity [odds ratio 2.22 (1.58–3.12)]. Over a quarter of the consultants were estimated to have clinically significant psychiatric morbidity, but only a very few had sought professional help in the last few months.

Implications. Hospital consultants should be made aware that the strategies they adopt to try to reduce the stress they experience through their work can influence their mental health both positively and negatively. Copyright © 2001 John Wiley & Sons, Ltd.
Participatory planning and design in a protracted conflict situation: applications with citizen peace‐building groups in Cyprus
Authors: Broome Benjamin J.
Published: September 2002

Since the demise of the ‘cold war’ that pitted Western Europe and the United States against the Soviet Union, the world's attention has been dominated by smaller inter‐state and intra‐state conflicts often centered on ethnic differences but with roots in superpower rivalries. An instructive example of such conflicts exists in Cyprus, which arose during the height of cold war politics and has outlasted both the cold war and many of the disputes that have consumed the majority of the world's attention in recent years. Since the physical division of the island in 1974 into separate Greek Cypriot and Turkish Cypriot zones, communication between ordinary citizens has been cut off, creating a serious obstacle to the development of a citizen peace‐building movement. Beginning in 1994, participatory planning and design methodologies have been applied with several groups of Greek Cypriots and Turkish Cypriots in a systematic attempt to develop and implement an agenda for citizen peace‐building activities. Using these methodologies the groups developed a heightened mutual understanding of the situation in Cyprus and a stronger sense of teamwork, while carrying out a variety of projects related to citizen peace building. This paper summarizes the activities involved in these efforts, poses a number of research questions about the applications of such methodologies, and draws upon the work in Cyprus to address these questions. Copyright © 2002 John Wiley & Sons, Ltd.
Marking the unmarked: using drama cross‐culturally in teacher education in New Zealand
Authors: Greenwood Janinka
Published: September 2002

Recently, following initiatives from the local people, a leading college of education in New Zealand ran an outpost teacher training programme in a remote Maori community in the far north. Part of that programme involved workshops that used drama as a participatory process to explore students' understandings of their goals and their relationship to the socio‐political context in which they worked. This paper reports on some of the understandings of cross‐cultural negotiation that were made explicit through the workshops. It also asks what we mark as difference and what assumptions we make, through not marking, about what is normal. At the very least the programme as a whole was successful in providing a group of culturally appropriate teachers for the region. However, this paper suggests that there are further implications for teacher training within the experience. Copyright © 2002 John Wiley & Sons, Ltd.
Web engineering: now and beyond
Authors: Myerson Judith M.
Published: September 2002

Since 1997, interest in Web engineering has been growing and will continue to grow as Web‐based systems become critical elements in a large number of applications. Web engineering is specifically targeted toward the design, analysis, implementation and other aspects of successful development and deployment of large, complex Web‐based systems.JUDITH MYERSONassesses the tools and models in current use. Copyright © 2001 John Wiley & Sons, Ltd.
Connectivity provisioning with security attributes
Authors: Tripunitara Mahesh V. , Spafford Gene
Published: September 2002

MAHESH TRIPUNITARA and GENE SPAFFORD discuss the problem of connectivity provisioning with security attributes. They then discuss the features of a piece of software that solves the problem. Also discussed are the benefits to a service provider and its customers from adopting the paradigm and the software solution. Copyright © 2001 John Wiley & Sons, Ltd.
Parallel and distributed computing
Authors: Wismüller Roland
Published: September 2002

After a decade of research, parallel processing is just becoming a standard instrument of high performance computing, which is used as naturally as any other specialised programming technique. ROLAND WISMÜLLER highlights some interesting trends in Concurrency and Computation: Practice and Experience. Copyright © 2001 John Wiley & Sons, Ltd.
Inhibition of autonomic nerve‐mediated inotropic responses in guinea pig atrium by bafilomycin A
Authors: Hong S.J.
Published: September 2002

Neurosecretory vesicles actively accumulate neurotransmitter by consuming proton motive force generated by vacuolar H+‐ATPase (V‐ATPase). The effects of bafilomycin A, a macrolide antibiotic that inactivates V‐ATPase, on nerve stimulation‐mediated inotropic responses of the left atrium were studied to explore the role of the enzyme in the cholinergic and adrenergic neurotransmissions. On field stimulation, the contractility of paced atrium exhibited initial atropine‐sensitive depression followed by propranolol‐sensitive facilitation. Both the negative and positive inotropic effects were abolished by bafilomycin A. The inhibitions were irreversible and followed a similar time course and the inhibitory effects were accelerated by intense nerve stimulation. In contrast, bafilomycin A had no effect on the inotropic responses produced by muscarinic acetylcholine or α‐adrenergic receptor agonist. Stimulation of neuronal nicotinic acetylcholine receptor also elicited biphasic changes of contractile force, which were depressed by bafilomycin A. Compared with the inhibitory effects on field stimulation, the depressions progressed slowly and incompletely. The results suggest that inhibition of V‐ATPase depressed the synaptic transmissions at autonomic nerve–muscle junctions. Furthermore, bafilomycin A preferentially inhibited neurotransmitter release emanating from the immediately releasable pool. Synapse 45:200–205, 2002. © 2002 Wiley‐Liss, Inc.
LY293558, an AMPA glutamate receptor antagonist, prevents and reverses levodopa‐induced motor alterations in Parkinsonian rats
Authors: Marin C. , Jiménez A. , Bonastre M. , Vila M. , Agid Y. , Hirsch E.C. , Tolosa E.
Published: September 2002

To evaluate the possible involvement of glutamate AMPA receptor‐mediated mechanisms in levodopa‐induced motor fluctuations, we investigated the effects of LY293558, a competitive AMPA receptor antagonist, on levodopa‐induced motor alterations in rats with unilateral 6‐OHDA lesion. Acute and chronic administration of LY293558 was studied to evaluate the possible reversion or prevention of these levodopa effects. In the first set of experiments, rats were treated with levodopa (25 mg/kg with benserazide, twice daily, i.p.) for 22 days and on day 23 LY293558 (5 mg/kg, i.p.) was administered immediately before levodopa. In the second set of experiments, rats were treated daily for 22 days with levodopa and LY293558 (5 mg/kg, twice daily, i.p.). In the third set of experiments, the effect of LY293558 (5 mg/kg, i.p.) administration on selective dopamine D‐1 (SKF38393, 1.5 mg/kg, s.c.) and D‐2 agonist (quinpirole, 0.1 mg/kg, i.p.)‐induced rotational behavior after daily levodopa treatment was studied. The duration of the rotational behavior induced by chronic levodopa decreased by 30% after 22 days. Acute administration of LY293558 on day 23 reversed this effect. The group of animals that were chronically treated with levodopa and LY293558 did not show the decrease in this motor response duration. Chronic levodopa treatment attenuated the rotational response to the D‐1 agonist SKF38393 and increased the response to the D‐2 agonist quinpirole. LY293558 did not reverse the effect of levodopa on rotational behavior induced by the D‐1 agonist but significantly reduced the rotational response to the D‐2 agonist in levodopa‐treated animals by 40%. Our results demonstrate that an AMPA receptor antagonist reverses and prevents levodopa‐induced motor alterations in parkinsonian rats and that this effect on motor fluctuations induced by chronic levodopa is probably due to a modulation of the indirect output pathway of the basal ganglia. Synapse 42:40–47, 2001. © 2001 Wiley‐Liss, Inc.
Seismic tests on a 16‐storey cast‐in‐place r/c building, and stochastic simulation results
Authors: Zaicenco A. , Alkaz V.
Published: September 2002

Records of the dynamic response of a 16‐storey cast‐in‐place reinforced concrete apartment building subjected to moderate‐magnitude (Mw < 7·0) earthquakes were performed before and after three recent significant Vrancea earthquakes. They are compared with random vibration simulation results based on a newly developed computer program and with an FEM linear model of the building, employing time‐history analysis. Theoretical investigations fitted to the results of the tests confirmed the validity of the approaches used and demonstrate satisfactorily good compatibility of the simulated and observed structural responses. The seismic records from the test building (str. Roz 15, Kishinev, Moldova), consisting of displacements and accelerations, were taken in ‘free‐field’, and at the foundation, the 8th storey and the top of the building. Copyright © 2001 John Wiley & Sons, Ltd.
X‐ray fluorescence analysis at the naval research laboratory
Authors: Gilfrich John V.
Published: September 2002

In the 50 years that the Naval Research Laboratory has been involved in x‐ray fluorescence analysis, there have been many developments which have made the technique what it is today. Many of the advances owe at least part of their success to the contributions made by the scientists of a specific group. This essay will present one man's opinion of the significant work by members of that group, as related to the impact that x‐ray fluorescence analysis has had on the field of analytical chemistry in general. Published in 2001 by John Wiley & Sons, Ltd.