bluuebunny/crossref_metadata_2025 huggingface dataset:
The outcomes of a longitudinal study of non‐organic failure‐to‐thrive
Authors: Iwaniec Dorota , Sneddon Helga , Allen Sarah
Published: October 2003

Individuals who had failed‐to‐thrive for non‐organic reasons received psychosocial intervention which was tailor‐made to their particular needs during childhood. Their progress was followed up over 20 years later, including their physical growth and social and cognitive functioning. Not all clients showed the same outcomes. The quality of the parental relationship and the reason for the growth‐faltering were found to be related to the outcomes at 20 years. Unless they experienced a positive and sustained change in their life or circumstances, individuals who had experienced abuse showed poorer outcomes than those whose growth‐faltering had been thought due to neglect, lack of parenting or feeding difﬁculties. Abuse tended to be a contributing factor to growth‐faltering more frequently in families where the parents were observed to have a poor relationship with each other. However, a signiﬁcant change in the quality of care given to the child and the emotional environment experienced by them resulted in positive outcomes 20 years later despite experiencing abuse during childhood. Copyright © 2003 John Wiley & Sons, Ltd.
Novel Fabrication of Conductive Polymers Contained Micro‐Array Gas Sensitive Films Using A Micromanipulation Method
Authors: Jung H.‐S. , Shimanouchi T. , Morita S. , Kuboi R.
Published: October 2003

A novel method for fabricating a micro gas sensor film on an indium tin oxide (ITO) electrode patterned using micro‐machining technology was developed. A micromanipulation system equipped with a counter electrode (Au; Ø10 μm) and a microsyringe, which was connected to a microinjection system, was first constructed. With this system, micro gas sensor arrays could be successfully prepared on ITO electrodes. Two kinds of micro gas sensor films were prepared, based on polythiophene (PTh) and poly(3‐n‐dodecylthiophene) (PD). The response behavior of conventional PTh and micro‐PTh films against NH3 at three different operating temperatures (25, 40 and 60 °C) was investigated by measuring the resistance of the film. With the micro‐PTh film, a reversible response was observed against NH3 when measured at 40 and 60 °C. In addition, the responsive characteristics of the microsensor films against different testing gases were examined at the three operating temperatures. The resistance of the microsensor films of PTh and PD changed considerably, depending on the type of testing gas, allowing these sensor films to be used for the detection of various gases. Furthermore, the microsensor films had a high stability compared with conventional films prepared from the same polymer.
Highly Selective and Sensitive Perchlorate Sensors Based on Some Recently Synthesized Ni(II)‐Hexaazacyclotetradecane Complexes
Authors: Ganjali Mohammad Reza , Yousefi Mohammad , Poursaberi Tahereh , Naji Leila , Salavati‐Niasari Masoud , Shamsipur Mojtaba
Published: October 2003

Three nickel(II)‐hexaazacyclotetradecane complexes were studied to characterize their abilities as perchlorate ion carrier in PVC membrane electrodes. The electrodes based on these complexes exhibit Nernstian responses for ClO$\rm{ {_{4}^{-}}}$ over very wide concentration ranges (1.0×10−1 −5.0×10−7 M) with detection limits of 2.0×10−7 −5.0×10−7 M (20–50 ng/mL). The sensors show very good selectivity for ClO$\rm{ {_{4}^{-}}}$ ion in comparison with the most common organic and inorganic anions. The responses of the proposed electrodes are independent of pH in the range of 3.5–11.0. The perchlorate selective membranes show fast response time (<10 s) and can be used for 4–12 weeks without any major deviation. The sensors were successfully used to determine the perchlorate ion in water, wastewater and human urine samples.
Quantitation of Metal Ions in Archaeological Glass by Abrasive Stripping Square‐Wave Voltammetry Using Graphite/Polyester Composite Electrodes
Authors: Doménech‐Carbó A. , Doménech‐Carbó M. T. , Osete‐Cortina L. , Gimeno‐Adelantado J. V. , Sánchez‐Ramos S. , Bosch‐Reig F.
Published: October 2003

A method for identifying Co, Cu, Sb, Sn, Fe, Zn, and Zr pigments in glasses using square‐wave voltammetry as the detection mode is described. It is based on the abrasive attachment of glass microsamples to graphite/polyester composite electrodes. Sample amounts less than 1 μg are used allowing for the study of archaeological samples. In all cases well‐defined anodic stripping peaks corresponding to the oxidation of metal deposits generated at potentials ranging from −0.6 to −1.6 V (vs. SCE) are obtained. This response is in agreement with that displayed by the corresponding metal oxides. Quantitative estimates of the relative population of metal ions in glasses are obtained from peak area measurements with an accuracy comparable to that obtained with SEM/EDX.
Electrochemical Study of s‐Triazine Herbicides Transfer Across the Water/1,2‐Dichloroethane Interface
Authors: Juárez A. V. , Yudi L. M.
Published: October 2003

The transfer of three s‐triazine herbicides, atrazine (ATR), propazine (PRO) and prometrine (PROM), across the water/1,2‐dichloroethane interface was investigated using cyclic voltammetry. A facilitated proton transfer mechanism from the aqueous to organic phase is demonstrated by the analysis of positive peak potential and peak current as a function of pH. It is shown that the determination of 2.5×10−5 M – 5×10−4 M concentration of herbicides in aqueous phase may be possible under the experimental conditions employed.
Electrocatalysis via Direct Electrochemistry of Myoglobin Immobilized on Colloidal Gold Nanoparticles
Authors: Liu Songqin , Ju Huangxian
Published: October 2003

The direct electron transfer between immobilized myoglobin (Mb) and colloidal gold modified carbon paste electrode was studied. The Mb immobilized on the colloidal gold nanoparticles displayed a pair of redox peaks in 0.1 M pH 7.0 PBS with a formal potential of –(0.108 ± 0.002) V (vs. NHE). The response showed a surface‐controlled electrode process with an electron transfer rate constant of (26.7 ± 3.7) s −1 at scan rates from 10 to 100 mV s−1 and a diffusion‐controlled process involving the diffusion of proton at scan rates more than 100 mV s−1. The immobilized Mb maintained its activity and could electrocatalyze the reduction of both hydrogen peroxide and nitrite. Thus, the novel renewable reagentless sensors for hydrogen peroxide and nitrite were developed, respectively. The activity of Mb with respect to the pseudo peroxidase with a KMapp value of 0.65 mM could respond linearly to hydrogen peroxide concentration from 4.6 to 28 μM. The sensor exhibited a fast amperometric response to NO2− reduction and reached 93% of steady‐state current within 5 s. The linear range for NO2− determination was from 8.0 to 112 μM with a detection limit of 0.7 μM at 3σ.
Hydrodynamic Modulation Voltammetry with a Dual Disk Chopped Flow‐Microjet Electrode (CF‐MJE)
Authors: Simjee Nafeesa , Unwin Patrick R. , Macpherson Julie V.
Published: October 2003

A novel form of hydrodynamic modulation voltammetry (HMV) is described, based on the periodic variation of mass transport in a microjet electrode (MJE) system, in combination with phase‐sensitive detection techniques. In the configuration developed, a jet of solution is fired from a nozzle that is aligned directly over the surface of a dual disk Pt‐Pt ultramicroelectrode (UME). The potential at each electrode is controlled separately. A rotating blade, positioned between the nozzle and the UME probe, is used to periodically interrupt flow to the electrode surface, resulting in modulation of the overall mass transfer rate between two defined extremes. The use of a dual disk UME enables two transport‐limited current signals to be recorded simultaneously, one for the analyte of interest, and the other for a ‘reference species’ (oxygen for the studies described herein). The latter current response corresponds to the variation in mass transport rate in the chopped flow (CF) arrangement and is used as the signal for phase sensitive detection of the analyte current. Studies of potassium hexachloroiridate (III) [IrCl$\rm{ {_{6}^{3-}}}$] oxidation in aqueous solution are used to demonstrate the capabilities of the technique. HMV in the CF‐MJE arrangement allows quantitative concentration measurements, down to at least 5×10−7 M.
Immobilized Cytochrome c Sensor in Organic/Aqueous Media for the Characterization of Hydrophilic and Hydrophobic Antioxidants
Authors: Beissenhirtz Moritz , Scheller Frieder , Lisdat Fred
Published: October 2003

A method for the characterization of antioxidants is introduced, which allows the measurement of pure hydrophilic and hydrophobic substances as well as complex cosmetic creams. The sensor is based on cytochrome c covalently immobilized on a gold wire electrode working in mixtures of phosphate buffer and organic solvents. It is combined with a superoxide generating enzyme system. The decrease of the superoxide concentration in the test solution by the added antioxidants is detected and used for the quantification of their antioxidative efficiency. Electrochemical properties of immobilized cytochrome c, such as formal potential and heterogeneous electron transfer rate constant, have been investigated in mixtures of aqueous buffer and DMSO, methanol, butanediol, and THF. The maximum organic solvent content for quasi‐reversible electrode behavior was correlated to spectroscopic measurements. The activity of the radical producing enzyme in such media was determined and the radical generation characterized. The antioxidative properties of pure substance such as ascorbic acid and Biochanin A as well as of five anti‐ageing cosmetic creams were studied. This showed also the influence of matrix composition on the efficiency of antioxidative supplements.
Mixed‐model splines for environmental time series
Authors: Street W. Scott , Edwards Don , Feller Robert J. , Coull Bruce C. , Stancyk Stephen E.
Published: October 2003

Eleven‐year biweekly time series of larval abundance of benthic fauna in a South Carolina salt marsh reveal, in the log scale, a clear annual pattern of alternating near‐linear growth and decay. The ecological processes governing these dynamics, particularly the dramatic year‐to‐year differences in annual maxima and minima, are mysterious. Traditional time series analyses (Fourier and ARIMA methods) can in some cases adequately mimic the patterns in these series, but they do little to enhance ecological understanding because they are not meaningfully parameterized. We model these series using floating‐knot linear splines in two ways: (i) as high‐dimensional non‐linear regression models with no forced similarity from year to year; and (ii) as a hierarchical spline model placing a probability distribution on annual maxima, minima, growth rate and decay rate across years, thereby enforcing some similarity in seasonal patterns. We discuss fitting and inference under both approaches; both yield excellent fits with ecologically interpretable results that can be used to shed light on governing processes. Results of a simulation study show that the hierarchical approach can yield substantial improvements in efficiency over the non‐linear regression approach, particularly for series with low interannual variability. Copyright © 2003 John Wiley & Sons, Ltd.
Parametric estimation for the location parameter for symmetric distributions using moving extremes ranked set sampling with application to trees data
Authors: Al‐Saleh Mohammad Fraiwan , Al‐Hadrami Said Ali
Published: October 2003

A modification of ranked set sampling (RSS) called moving extremes ranked set sampling (MERSS) is considered parametrically, for the location parameter of symmetric distributions. A maximum likelihood estimator (MLE) and a modified MLE are considered and their properties are studied. Their efficiency with respect to the corresponding estimators based on simple random sampling (SRS) are compared for the case of normal distribution. The method is studied under both perfect and imperfect ranking (with error in ranking). It appears that these estimators can be real competitors to the MLE using (SRS). The procedure is illustrated using tree data. Copyright © 2003 John Wiley & Sons, Ltd.
Analyzing weather effects on airborne particulate matter with HGLM
Authors: Dong Lee Yoon , Yun Sungcheol , Lee Youngjo
Published: October 2003

Particulate matter is one of the six constituent air pollutants regulated by the United States Environmental Protection Agency. In analyzing such data, Bayesian hierarchical models have often been used. In this article we propose the use of hierarchical generalized linear models, which use likelihood inference and have well developed model‐checking procedures. Comparisons are made between analyses from hierarchical generalized linear models and Danielset al.'s (2001) Bayesian models. Model‐checking procedure indicates that Danielset al.'s model can be improved by use of the log‐transformation of wind speed and precipitation covariates. Copyright © 2003 John Wiley & Sons, Ltd.
Accuracy of geostatistical prediction of yearly precipitation in Lower Saxony
Authors: Wameling Almuth
Published: October 2003

Geostatistical methods allow the interpolation of spatially referenced data. They allow the prediction of values for arbitrary points in the area of interest. From these point predictions, maps are created which display areas of low or high predicted values. Apart from three dimensional and raster plots, contour line maps are frequently used. Contours are lines with constant process values. The article describes two accuracy concepts of geostatistical predictions. Local errors describe the accuracy of individual point predictions as mean squared prediction errors. They do not describe adequately the precision of contour lines extracted from an interpolated surface. A method is proposed to construct horizontal confidence intervals for arbitrary contours. This method is based on the theory of conditional simulations and is applicable whenever a suitable simulation algorithm is found. In a case study, two geostatistical models are compared regarding both accuracy concepts. Results show that higher local precision need not induce higher contour line accuracy. It is concluded that the local error concept is not sufficient to evaluate the precision of a contour line map. Copyright © 2003 John Wiley & Sons, Ltd.
Design of the farm‐scale evaluations of genetically modified herbicide‐tolerant crops
Authors: Rothery Peter , Clark Suzanne J. , Perry Joe N.
Published: October 2003

The Farm‐Scale Evaluations (FSE) is a three‐year experiment to study the effects on farmland wildlife of the commercial management of four genetically modified herbicide‐tolerant (GMHT) crops—beet, maize, spring oil‐seed rape and winter oil‐seed rape. The experiment records abundance of a wide range of weed and invertebrates in the arable system. The FSE is a paired comparison arranged as a randomized block design with two treatments (GMHT and conventional crop management) and fields as blocks. The choice of the half‐field as the experimental unit is based on field availability, the primary focus on the vegetation, the need to reduce variability and gains in sampling effort. Farms and fields are selected to reflect the range of geographical variation and farming intensity for each crop. A power analysis shows that using about 60 fields per crop over the three years will be sufficient to detect differences of ecological significance. Copyright © 2003 John Wiley & Sons, Ltd.
Real‐time video postprocessing for deblocking and deringing on mediaprocessors
Authors: Gao Wenfeng , Mermer Coskun , Kim Yongmin
Published: October 2003

Blocking and ringing are two major artifacts in highly compressed images and videos coded by block‐based discrete cosine transform. Many existing deblocking and deringing algorithms are computationally very expensive and/or cannot produce satisfactory results at very low bit rates. We have developed an adaptive deblocking algorithm and a clustering‐based deringing algorithm. These algorithms can smooth out the blocking and ringing artifacts while preserving the strong edges and texture areas. In addition, our postprocessing algorithms have low computational cost. We have implemented them on a commercially available, programmable processor. For an image size of 352 × 288, our algorithms take only 3.17 ms, demonstrating the feasibility of real‐time video postprocessing. © 2003 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 161–168, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10052
Superresolution image reconstruction from blurred observations by multisensors
Authors: Ching Wai‐Ki , Ng Michael K. , Sze Kenton N. , Yau Andy C.
Published: October 2003

Superresolution image reconstruction refers to obtaining an image at a resolution higher than that of the camera (sensor) used in recording the image. In this article, we present a joint minimization model with an objective function setup that comprises three terms: the data‐fitting term (DFT), the regularization term for the reconstructed image, and the observed low‐resolution images. An alternating minimization iterative algorithm is presented to reconstruct the image. We also analyze the alternating minimization iterative algorithm and show that it converges globally for H1‐norm or total‐variation regularization that are functional for the reconstructed image. Numeric examples are given to illustrate the effectiveness of the joint minimization model and the efficiency of the algorithm. © 2003 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 153–160, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10053
Subband decomposition strategies for object‐based image coding
Authors: de Souza Marcio Albuquerque , Acocella Emilio Carlos , Alcaim Abraham
Published: October 2003

In order to attain perfect reconstruction, subband decomposition of arbitrarily shaped objects requires special strategies to deal with the decimation problem. One of the two strategies described in this paper (scheme 1) inserts pixels with amplitudes equal to the mean values of the neighboring ones belonging to the object. The requirement of transmitting (coding) these pixels reduces the coding gain and is avoided by the second strategy (scheme 2) examined in this paper. This strategy determines specific values of the pixels added to the object in such a way that they result in predefined amplitudes after decimation. For this reason, this method outperforms scheme 1. PSNR versus bit rate are presented for two objects. © 2003 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 179–187, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10054
Fast template matching using correlation‐based adaptive predictive search
Authors: Sun Shijun , Park HyunWook , Haynor David R. , Kim Yongmin
Published: October 2003

We have developed the Correlation‐based Adaptive Predictive Search (CAPS) as a fast search strategy for multidimensional template matching. A 2D template is analyzed, and certain characteristics are computed from its autocorrelation. The extracted information is then used to speed up the search procedure. This method provides a significant improvement in computation time while retaining the accuracy of traditional full‐search matching. We have extended CAPS to three and higher dimensions. An example of the third dimension is rotation where rotated targets can be located while again substantially reducing the computational requirements. CAPS can also be applied in multiple steps to further speed up the template matching process. Experiments were conducted to evaluate the performance of 2D, 3D, and multiple‐step CAPS algorithms. Compared to the conventional full‐search method, we achieved speedup ratios of up to 66.5 and 145 with 2D and 3D CAPS, respectively. © 2003 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 169–178, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10055
Identification of local interaction models with imperfect location data
Authors: Conley Timothy G. , Topa Giorgio
Published: October 2003

This paper considers the problem of estimating a local interaction model defined at the level of individual agents, in the absence of perfect information about agent locations in the relevant socio‐economic space. We consider two types of data limitations: one in which individual locations are measured with error, the other in which location information is correct but only up to some spatial region (e.g., census tracts or zip codes). Our results indicate that the model parameters are not identified almost surely in the former situation, whereas identification is preserved in the latter. We also suggest a potential estimation strategy that can yield useful information about the likely range of parameters even when point identification fails. Copyright © 2003 John Wiley & Sons, Ltd.
Peer effects, financial aid and selection of students into colleges and universities: an empirical analysis
Authors: Epple Dennis , Romano Richard , Sieg Holger
Published: October 2003

This paper develops a model in which colleges seek to maximize the quality of the educational experience provided to their students. We deduce predictions about the hierarchy of schools that emerges in equilibrium, the allocation of students by income and ability among schools, and about the pricing policies that schools adopt. The empirical findings of this paper suggest that there is a hierarchy of school qualities which is characterized by substantial stratification by income and ability. The evidence on pricing by ability is supportive of positive peer effects in educational achievement from high ability at the college level. Copyright © 2003 John Wiley & Sons, Ltd.
Interdependence in worker productivity
Authors: Rees Daniel I. , Zax Jeffrey S. , Herries Joshua
Published: October 2003

This paper investigates interactions between co‐worker productivity levels in a rich empirical context. Workers have unambiguous output measures, compensation that depends on individual and group output to differing degrees and potential peers beyond their immediate work group. Important productivity interdependencies exist, which could arise from the group‐based component of compensation, peer pressure, common supervisors or information exchanges, but not group‐based output or technological interdependence. Workers with the strongest individual incentives seem least sensitive to these interactions. In contrast, they are important to workers with no individual incentives. For these workers, peer pressure must be a powerful influence. Copyright © 2003 John Wiley & Sons, Ltd.
Correlations between sisters and neighbouring girls in their subsequent income as adults
Authors: Page Marianne E. , Solon Gary
Published: October 2003

This study uses data on sisters and neighbouring girls in the Panel Study of Income Dynamics to estimate sister and neighbour correlations in adult income. Our results suggest that the income resemblance between sisters stems more from growing up in the same family than from growing up in the same neighbourhood. We also find that much of the neighbour correlation is explicable in terms of the large income differential between urban and non‐urban areas combined with the strength with which urbanicity of childhood neighbourhood predicts urbanicity of adult location. This pattern is subject to a variety of interpretations, but it is quite different from the usual view of neighbourhood effects. Copyright © 2003 John Wiley & Sons, Ltd.
Neighbourhood effects and housing demand
Authors: Ioannides Yannis M. , Zabel Jeffrey E.
Published: October 2003

In this paper, we estimate a model of housing demand with neighbourhood effects. We exploit special features of the national sample of the American Housing Survey and properties of housing markets that allow us to create ‘natural’ instruments and therefore identify the impact of social interactions. We find evidence of both endogenous and contextual neighbourhood effects. We report two alternative sets of estimates for neighbourhood effects that differ in terms of the instruments we use for estimating the model. When the endogenous neighbourhood effect is large the respective contextual effects are weak, andvice versa. The elasticity of housing demand with respect to the mean of the neighbours' housing demands (the endogenous effect) ranges from 0.19 to 0.66 and is generally very significant. The contextual effects are also very significant. A key such effect, the elasticity with respect to the mean of neighbours' permanent incomes, ranges from 0.17 to 0.54. Copyright © 2003 John Wiley & Sons, Ltd.
Does peer ability affect student achievement?
Authors: Hanushek Eric A. , Kain John F. , Markman Jacob M. , Rivkin Steven G.
Published: October 2003

Empirical analysis of peer effects on student achievement has been open to question because of the difficulties of separating peer effects from other confounding influences. While most econometric attention has been directed at issues of simultaneous determination of peer interactions, we argue that issues of omitted and mismeasured variables are likely to be more important. We control for the most important determinants of achievement that will confound peer estimates by removing student and school‐by‐grade fixed effects in addition to observable family and school characteristics. The analysis also addresses the reciprocal nature of peer interactions and the interpretation of estimates based upon models using past achievement as the measure of peer group quality. The results indicate that peer achievement has a positive effect on achievement growth. Moreover, students throughout the school test score distribution appear to benefit from higher achieving schoolmates. On the other hand, the variance in achievement appears to have no systematic effect. Copyright © 2003 John Wiley & Sons, Ltd.
Social planning: past, present, and future
Authors: Bromley Ray
Published: October 2003

This article discusses the history of the idea of social planning, and of the pioneering Masters Programme in Social Planning established at the University of Wales Swansea in 1973. Swansea's initiative in social planning led to the creation of the University's Centre for Development Studies (CDS), and it broadened development studies as an academic and policy field. Social planning is a controversial term because it has sometimes been associated with social engineering and totalitarianism. Nevertheless, it has a very important intellectual and policy agenda, and if the word ‘planning’ proves a liability it can be replaced by ‘policy’ or ‘strategy’. The major questions reviewed at CDS‐Swansea in the 1970s are still pertinent, and new dimensions have been added through growing concerns for nation‐building, sustainability, democracy, gender equity and human rights. Copyright © 2003 John Wiley & Sons, Ltd.
Re‐approaching social development: a field of action between social life and policy processes
Authors: Arce Alberto
Published: October 2003

This article reflects on contemporary social development, and suggests that we need to initiate a process of thinking about a post neo‐liberal development agenda. As a step in this direction, it is suggested we need to re‐approach the social as a conceptual category in order to consider social analysis not simply as an epiphenomenon of economic development, but as a social sphere in its own right. To start thinking about this process, the social is approached through the metaphor of the middle ground, which acts as a device to help conceptualize a field of action between social life and policy processes. Exploration of this field of action is used to consider changes in the policy community by focusing on the implications of ‘liberal freedom’ and ‘negative freedom’ for people's actions. This provides a basis to take a critical view of concepts such as social capital and approaches such as sustainable livelihoods, reflect neo‐liberal social development discourses. This leads us to argue for the need to consider the potential of contemporary biological science and of social movements for reinvigorating our understanding of social development. Copyright © 2003 John Wiley & Sons, Ltd.
Patterns of difference and practical theory: researching the new poverty strategy processes in Africa
Authors: Booth David
Published: October 2003

A collection on the past and future of social‐development analysis provides an opportunity to reflect and connect. This article reflects on a ten‐year‐old book called Rethinking Social Development and connects it with a recent study of Poverty Reduction Strategy processes in Africa. It argues that the recent work fills a gap in the empirical basis of the book, adding force to its main arguments—about dominance, agency and diversity in development—while also speaking to some unresolved issues: about the place of macro‐institutional analysis, the limits of ‘actor orientation’ and the generation of practical theory. Copyright © 2003 John Wiley & Sons, Ltd.
Mainstreaming the social dimension into the overseas development administration: a partial history
Authors: Eyben Rosalind
Published: October 2003

Written by the first Chief Social Development Adviser of the Overseas Development Administration (now called the Department for International Development), this article describes when, why and how an understanding of the social dimension became mainstreamed into the policy and practice of the British aid programme. Exploring the growth within the context of the changing political aid environment of the final quarter of the last century, the history of social development within the British aid programmes is described from its origins in the mid‐1970s up to 1997. It asks how it was that a new specialist group of social analysts was established as part of the agency's bureaucratic machinery and compares this with the World Bank's experience. The article concludes by briefly considering the challenges facing social development expertise following 1997. Copyright © 2003 John Wiley & Sons, Ltd.
Why has it ended up here? Development (and other) messages and social connectivity in northern Orissa
Authors: Rew Alan
Published: October 2003

In northern Orissa, official messages about government schemes and UN millennium development goals arrive in the villages; but the subsequent action is perceived as unpredictable, with latent costs, and often not matched to community demands. Messages sent by villagers illustrate the principle of ‘self‐organizing connectivity’; they travel along complex, indeterminate, social routes yet arrive in good time and without charge; and bring new ways of coping with poverty. The research suggests that significant social development gains are at risk from over‐concentration on global millennium development goal supply targets. Insufficient attention is being paid to community demands. Context sensitive and democratised social analysis as a key part of implementation is recommended. Copyright © 2003 John Wiley & Sons, Ltd.
Generation of orthogonal curvilinear meshes in three dimensions
Authors: Meliani H. , Djebbar J.A. , de Cogan D.
Published: October 2003

In this article a method of curvilinear orthogonal mesh generation in three dimensions is described. This technique is based on the solution of elliptic equations in two and three dimensions. Frequently, the generated meshes are not quite orthogonal; hence a modified Davies' algorithm is used to solve this problem. The effectiveness of the method is demonstrated using examples based on electromagnetic field problems. These curvilinear meshes have the ability to correctly represent non‐uniform geometry, as well as regions containing singularities or high gradient fields. Copyright © 2003 John Wiley & Sons, Ltd.
The computation of the input impedance of a biconical antenna by means of a method of segmentation based on 3D finite elements
Authors: Ma Gil José , Rubio Jesús , Zapata Juan
Published: October 2003

The analysis of structures with complex geometries leads to the use of three‐dimensional numerical methods. Such devices can be unmanageable unless a segmentation technique is applied. In this work, a hybrid 3D finite‐element‐mode matching method, based on the generalized admittance matrix (GAM) is applied to the computation of the input impedance of a biconical antenna fed by a cylindrical cavity loaded with resonant slots and matched by a coupling network composed of three multi‐ridge circular irises and sections of circular waveguides. The structure is segmented into regions which are analysed separately and, by means of linking the partial matrices calculated, the generalized scattering matrix (GSM) is obtained. In order to validate the method, numerical results and measurements are compared. Copyright © 2003 John Wiley & Sons, Ltd.
Sleeve monopole on a circular ground‐plane
Authors: Shen Zhongxiang , MacPhie Robert H.
Published: October 2003

This paper presents a modal‐expansion analysis of a sleeve monopole antenna on a finite ground‐plane. Two perfectly conducting plates (one above the monopole and the other under the ground‐plane) are introduced to confine the modeling region and to facilitate the modal‐expansion analysis. The resulting guided‐wave structure is then divided into a number of regions and the electromagnetic field components in each region are expanded into the summation of its modal functions. The surface current distribution on the monopole and the antenna's input impedance and radiation pattern are obtained by finding the expansion coefficients through matching the tangential field components across the regional interfaces. Calculated results by the modal‐expansion method agree well with measured results for the return loss of a sleeve monopole fed through a circular ground‐plane by a coaxial probe. Numerical results for the surface current distribution, input impedance, and radiation pattern of a sleeve monopole on a circular ground plane are presented and discussed. Copyright © 2003 John Wiley & Sons, Ltd.
TLM models of waves in moving media: refinements and dispersion analysis
Authors: O'Connor William J
Published: October 2003

Two recent papers about transmission line matrix (TLM) models of waves in moving media used notional diodes to achieve the appropriate direction‐dependent wave speeds. Despite the algorithm's demonstrated success, the operation of the diodes might be criticized for being non‐physical from a circuit theory perspective. Alternative circuit models are here developed that avoid this objection, being based on wave two‐ports and standard circuit theory components. Their operation obeys the same numerical algorithm derived using the diodes, thereby confirming the validity of the original computational scheme. Furthermore these circuits lead more easily to the direction‐dependent wave speed expressions and provide exact analytic results for dispersion and attenuation effects, which are here presented and discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Transmission‐line matrix models for solving transient problems of diffusion with recombination
Authors: Gui Xiang , de Cogan Donard
Published: October 2003

Starting from the general telegrapher's equation, we investigate two nodal network constructions for modelling diffusion with recombination by means of the transmission‐line matrix (TLM) method. The diffusion effect is modelled by the series and shunt capacitance in one approach, and by the series inductance and shunt resistance in the other. Both approaches use the series and shunt resistances to model the recombination effect. The constraint of using both TLM networks for solving transient problems of diffusion with recombination is found to be identical in terms of the physics behind the numerical routines. A practical way of determining the spatial resolution and iteration time step for accurate TLM numerical computations is suggested based on a simple frequency analysis. Copyright © 2003 John Wiley & Sons, Ltd.
Use of lossless transmission‐line segments and shunt resistors for TLM diffusion modelling
Authors: Gui Xiang
Published: October 2003

In diffusion modelling by means of the transmission‐line matrix (TLM) method, a nodal arrangement of using lossless transmission‐line segments and series resistors is almost exclusively adopted and is currently considered as a standard approach. In this paper, the use of shunt resistors instead of series resistors is shown to represent an equally valid configuration. As a starting point, we have derived the telegrapher's equation in its most general form for TLM modelling of diffusion processes. A general algorithm based on the shunt‐resistor TLM model for implementing a numerical solution of the diffusion equation in multiple dimensions is given. Fundamental analysis and calculated examples confirm that the alternative shunt‐resistor configuration does not exhibit the unwanted absorption effects suggested by a recent paper (Internat. J. Numerical Model.: Electronic Networks, Devices and Fields 2002; 15:261). Copyright © 2003 John Wiley & Sons, Ltd.
Computation of STM images of carbon nanotubes
Authors: Lambin P. , Márk G. I. , Meunier V. , Biró L. P.
Published: October 2003

Scanning tunneling microscopy (STM) is the only probing technique that allows for the investigation of both the topography and the electronic structure of carbon nanosystems at a subnanometer resolution. The interpretation of the STM images of carbon nanostructures involves complications that are normally absent in the study of planar crystalline surfaces. The complications typically appear from a number of quantum effects responsible for distortions in the microscope image of a nano‐object. Because of these difficulties, computer simulation plays an extremely important role in the analysis of experimental data. In the current article, we report on two theoretical approaches developed for aiding in the interpretation and understanding of the formation of the STM image of a nanotube: first, the quantum mechanical dynamics of a wave packet, which allows for the modeling of the flow of the tunneling current between a tip and a nanotube supported by a substrate; and, second, a tight‐binding perturbation theory that allows for the explicit calculation of realistic STM images and scanning tunneling spectra of carbon nanostructures. An atlas of computed STM images is provided for a series of 27 single‐wall nanotubes with diameter around 1.3 nm. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Further observations of projectile‐z dependence in target parameters of modified Bethe–Bloch theory
Authors: Porter L. E.
Published: October 2003

Several studies of a systematic dependence on projectile atomic number (z) of the values of the two prominent target parameters of modified Bethe–Bloch theory have been published over the past 3 years. The target materials for which parameter values were extracted from stopping power measurements by analyses with modified Bethe–Bloch theory were initially the four organic (co)polymers—formvar, polyimide, polysulfone, and vyns—and the cobalt‐base alloy, havar. An additional (in press) study for the frequently utilized target materials, aluminum and copper, and for titanium and zinc targets, revealed considerable corroboration of the initially discovered trends. The scope of the investigation has been enlarged in the current study to include analyses of measurements with light projectiles of the stopping powers of 11 halogenated hydrocarbons, and with both light projectiles and heavy ions of the stopping powers of kapton (a polyimide), polycarbonate, havar, and nickel. The results of this, most recent, study are also generally corroborative of the previously established pattern of behavior of the two prominent parameters of modified Bethe–Bloch theory. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
A novel method for generating approximate wavefunctions
Authors: Weiner B.
Published: October 2003

Molecular Hamiltonians are constituted by momentum operators (e.g., kinetic energy and interaction with electromagnetic radiation), local potential operators (e.g., electron–electron coulomb, electron–nucleus, and electron–external field interactions), and spin operators. In general, the effect of transformations that generate states from a reference state is to destroy this form. Here it is shown how one can generate all pure states by the action of a commutative semigroup of transformations that are diagonal in the space–spin coordinate representation that do not destroy this form and thus maintain the physical interpretability of effective Hamiltonians. Using such transformations, we formulate an approximation theory that has physical interpretation at all orders. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Internal energy and magnetic moment of three‐dimensional ferromagnets
Authors: Misra Anirban , Klein D. J. , Datta Sambhu N. , March N. H.
Published: October 2003

The unique relationship between the reduced internal energy and magnetic moment is investigated for a three‐dimensional ferromagnet on the basis of a many‐body k‐space spin‐wave solution of an anisotropic Heisenberg Hamiltonian of general site spin S. Spin‐wave interactions up through terms quartic in Boson creation and annihilation operators are considered. The three‐dimensional lattice on which the Hamiltonian is developed is in terms of the so‐called “bundle representation” for three independent axes as applicable to systems of orthorhombic and higher symmetry. The Hamiltonians considered are general enough to encompass models ranging from the ordinary (isotropic) Heisenberg Hamiltonian to the anisotropic Ising Hamiltonian, all for general values of S. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Unified quantum molecular dynamics method based on centroid molecular dynamics and semiempirical molecular orbital theory
Authors: Ohta Yasuhito , Ohta Koji , Kinugawa Kenichi
Published: October 2003

We have developed a unified quantum molecular dynamics method, in which the centroid molecular dynamics including the quantum effect of atomic nuclei is unified with the semiempirical molecular orbital calculation for the atomic configuration generated in the molecular dynamics. This unified method has successfully been applied to a couple of diatomic molecular systems for examining its performance. The method has yielded excellent agreement with exact quantum results and taken sufficiently short CPU time for practical use. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Inclusion of Rydberg orbitals in semiempirical calculations on excited states?
Authors: Head John D.
Published: October 2003

Semiempirical methods, especially Zerner's INDO/S method, are well‐established tools for theoretically investigating the low‐lying valence excitations in large biologically important molecules. In recent years ab initio calculations have shown that low‐lying excited states arise from both valence and Rydberg states. Using experience from ab initio calculations we explore whether Rydberg orbitals can be successfully added to semiempirical procedures. The procedure, implemented in Zerner's INDO/S method, consists of adding a shell of Rydberg orbitals at a single center on the molecule. New integral approximations are introduced to take into account that a Rydberg orbital has a much greater radial extent than the valence basis functions and allow mixing between the valence and Rydberg excited states. Parameters for the Rydberg orbitals are obtained by fitting to the experimental vertical excitation energies for ethylene and benzene while keeping the original valence orbital parameters fixed. The procedure is then evaluated by examining the vertical excitation energies computed for t‐butadiene, all‐trans hexatriene, cyclobutadiene, pyrrole, and furan. Overall we obtain encouraging results suggesting that Rydberg orbitals can realistically be treated by a semiempirical procedure. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Global optimization of SixHy at the ab initio level via an iteratively parametrized semiempirical method
Authors: Ge Yingbin , Head John D.
Published: October 2003

Previously we searched for the ab initio global minima of several SixHy clusters by a genetic algorithm in which we used the AM1 semiempirical method to facilitate a rapid energy calculation for the many different cluster geometries explored. However, we found that the AM1 energy ranking significantly differs from the ab initio energy ranking. To better guarantee locating the ab initio global minimum while retaining the efficiency of the AM1 method, we present an improved iterative global optimization strategy. The method involves two separate genetic algorithms that are invoked consecutively. One is the cluster genetic algorithm (CGA), mentioned above, to find the semiempirical SixHy cluster global minimum. A second and separate parametrization genetic algorithm (PGA) is used to reparametrize the AM1 method using some of the ab initio data generated from the CGA to form a training set of different reference clusters but with fixed SixHy stoichiometry. The cluster global optimization search (CGA) and the semiempirical parametrization (PGA) steps are performed iteratively until the semiempirical GA reparametrized AM1 (GAM1) calculations give low‐energy optimized structures that are consistent with the globally optimized ab initio structure. We illustrate the new global optimization strategy by attempting to find the ab initio global minima for the Si6H2 and Si6H6 clusters. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Computational prediction of relative group polarizabilities
Authors: Jin Ping , Brinck Tore , Murray Jane S. , Politzer Peter
Published: October 2003

Earlier work has shown that molecular polarizabilities correlate well with the quantity V/IS,ave, where V is the volume of the molecule and IS,ave is the average value of the local ionization energy on its surface. We now extend this to group polarizabilities; we computed V/IS,ave for four common chemical groups (NO2, CH3, NH2, and OH) in a variety of molecules. The transferabilities of IS,ave, V, and V/IS,ave are examined, as well as the correlation between V/IS,ave and literature polarizabilities of CH3, NH2, and OH. This permits the value for NO2 to be predicted (α = 2.77 Å3). The dependence of IS,ave, and therefore V/IS,ave, upon the remainder of the molecule is discussed. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Mechanism of phosphoryl transfer in kinases investigated by semiempirical calculations
Authors: Hutter Michael C. , Helms Volkhard
Published: October 2003

The reaction mechanism of the enzymatic phosphoryl transfer in active site model systems of three kinases has been studied previously by AM1 semiempirical molecular orbital calculations. The computed mechanism shows the synchronous shift of a proton to the transferred PO3 group in all our kinase model systems despite the chemical variety of the phosphoryl acceptors and the distinct differences of the associated energy profiles. Here, computed geometries are compared with X‐ray crystallographic data and results of density functional calculations. Further, the presence of the transition‐state analog aluminum fluoride was found to alter the protonation state of the phosphoryl acceptors. In combination with recent experimental studies we suggest that the concerted mechanism of phosphoryl transfer is common to all kinases. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Crystal orbital study of polycarbonyl
Authors: Podeszwa Rafał , Bartlett Rodney J.
Published: October 2003

We present crystal orbital calculations of polymeric carbon monoxide (polycarbonyl) by means of Hartree–Fock (HF), density functional theory (DFT), and second‐order many‐body perturbation theory [MBPT(2)] methods. The calculations are performed with improved integral evaluation routines. The results include optimized geometries obtained with HF and DFT methods and MBPT(2) correlation energies calculated at fixed geometry. The chain forms a zig‐zag of equidistant carbonyl groups. The results indicate the relative stability of polycarbonyl and may suggest the possibility of experimental detection of metastable forms of the polymer. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003