Search

This paper describes some of the results of a detailed farm-level survey of 32 small-scale cotton farmers in the Makhathini Flats region of South Africa. The aim was to assess and measure some of the impacts (especially in terms of savings in pesticide and labour as well as benefits to human health) attributable to the use of insect-tolerant Bt cotton. The study reveals a direct cost benefit for Bt growers of SAR416 ($51) per hectare per season due to a reduction in the number of insecticide applications. Cost savings emerged in the form of lower requirements for pesticide, but also important were reduced requirements for water and labour. The reduction -in the number of sprays was particularly beneficial to women who do some spraying and children who collect water and assist in spraying. The increasing adoption rate of Bt cotton appears to have a health benefit measured in terms of reported rates of accidental insecticide poisoning. These appear to be declining as the uptake of Bt cotton increases. However, the understanding of refugia and their management by local farmers are deficient and need improving. Finally, Bt cotton growers emerge as more resilient in absorbing price fluctuations.

This paper describes the results of research intended to explore the volatility inherent in the United Nations Development Programme's (UNDP) Human Development Index (HDI). The HDI is intended to be a simple and transparent device for comparing progress in human development, and is an aggregate of life expectancy, education and GDP per capita. Values of the HDI for each country are presented in the Human Development Reports (HDRs), the first being published in 1990. However, while the methodology is consistent for all countries in each year there are notable differences between years that make temporal comparisons of progress difficult. The paper presents the results of recalculating the HDI for a simplified sample of 114 countries using various methodologies employed by the UNDP. The results are a set of deviations of recalculated HDI ranks compared to the original ranks given in the HDRs. The volatility that can result from such recalculation is shown to be substantial (±10–15 ranks), yet reports in the popular press are frequently sensitive to movements of only a few ranks. Such movement can easily be accounted for by changes in the HDI methodology rather than genuine progress in human development. While the HDRs often carry warnings about the inadvisability of such year-on-year comparisons, it is argued that the existence of such a high-profile index and the overt presentation within league tables do encourage such comparison. Assuming that the HDI will be retained as a focal point within the HDRs, then it is suggested that greater focus be upon more meaningful and robust categories of human development (e.g. low, medium and high) rather than league tables where shifts of a few places, perhaps as a result of nothing more than a methodological or data artefact, may be highlighted in the press and by policy makers.

In this paper we describe a framework for deterministic adaptive control which involves logic-based switching among a family of candidate controllers. We compare it with more conventional adaptive control techniques that rely on continuous tuning, emphasizing how switching and logic can be used to overcome some of the limitations of traditional adaptive control. The issues are discussed in a tutorial, non-technical manner and illustrated with specific examples. (C) 2003 Elsevier Science B.V. All rights reserved.

This paper presents the results of:(a) On-farm trials (eight) over a two-year period designed to test the effectiveness of leguminous cover crops in terms of increasing maize yields in Igalaland, Nigeria.(b) A survey designed to monitor the extent of, and reasons behind, adoption of the leguminous cover crop technology in subsequent years by farmers involved, to varying degrees, in the trial programme.Particular emphasis was placed on comparing adoption of leguminous cover crops with that of new crop varieties released by a non-governmental organization in the same area since the mid 1980s. While the leguminous cover crop technology boosted maize grain yields by 127 to 136% above an untreated control yield of between 141 and 171 kg ha−1, the adoption rate (number of farmers adopting) was only 18%. By way of contrast, new crop varieties had a highly variable benefit in terms of yield advantage over local varieties, with the best average increase of around 20%. Adoption rates for new crop varieties, assessed as both the number of farmers growing the varieties and the number of plots planted to the varieties, were 40% on average. The paper discusses some key factors influencing adoption of the leguminous cover crop technology, including seed availability. Implications of these results for a local non-governmental organization, the Diocesan Development Services, concerned with promoting the leguminous cover crop technology are also discussed.

The Human Development Index (HDI) introduced by the United Nations Development Programme (UNDP) in 1990 has helped facilitate widespread debate amongst development researchers, practitioners and policy makers. The HDI is an aggregate index, calculated on an annual basis by the UNDP and published in its Human Development Reports, comprising measures of three components deemed by them to be central to development: W income (the gross domestic product per capita), (ii) education (adult literacy rate) and (iii) health (life expectancy at birth). The results of calculating the HDI are typically presented as country/regional league tables, and provide a quick means for policy makers and others to judge performance. Perhaps partly because of the relative simplicity of the index, the HDI has managed to achieve a level of acceptance and use amongst politicians and policy makers that has yet to emerge with any indicator of sustainability. Indeed, despite its existence for 11 years, including nine years after the Rio Earth Summit, the HDI has not even been modified to take on board wider issues of sustainability. This paper will critically examine the potential for 'greening' the HDI so as to include environmental and resource-consumption dimensions. Copyright (C) 2003 John Wiley & Sons, Ltd and ERP Environment.

This research described in this paper examined the impact of varietal mixtures on pest management utilising a model system of partial insecticide applications. In six field experiments conducted in 1995 and 1996 in Igalaland, Kogi State, Nigeria varietal mixtures were simulated through the application of systemic insecticide (carbofuran or furathiocarb) to a pre-determined percentage of a cowpea ( Vigna unguiculata ) crop. The objective was to examine and compare the pest damage on untreated cowpea plants grown in plots in which varying percentages of the cowpea plants were treated with insecticide. A secondary objective was to determine whether action of the foliage pests influenced flower production. The results showed that the presence of insecticide-treated plants reduced the level of leaf damage by Ootheca mutabilis Sahlberg and the densities of Aphis craccivora Koch populations on untreated plants. The greater the percentage of insecticide-treated plants the greater this reduction on the untreated plants. Meanwhile, the number of flowers found on the untreated plants increased suggesting the foliage pest damage reduced flower production.

Field experiments were established in which cowpea (Vigna unguiculata Walpers) was treated with a series of partial insecticide (carbofuran) application treatments to simulate (susceptible/resistant) varietal mixtures and a series of inter-crops with soybean (Glycine max). Treatments were sampled for damage by the foliage pests Ootheca mutabilis Sahlberg and Aphis craccivora Koch and for flower production. The soybean is likely to have provided both a mechanical barrier to pest movement and disruption to O. mutabilis through volatile allelochemicals. The comparison between the two treatment types would suggest whether similar mechanisms were the cause of pest reductions observed in partial insecticide applications on cowpea. The results suggested that the inter-cropping with soybean was not as effective in managing pest populations as a partial insecticide application and could even increase pest numbers. Further examination of the data from the partial insecticide application treatments appeared to show that the pest infestation was lower on the untreated plants closest to the insecticide-treated plants. This could be as a result of pest redistribution onto insecticide-treated plants after initial colonisation. The implications of this, in terms of pest resistance management are discussed.

This paper deals with the problem of switching between several linear time-invariant (LTI) controllers-all of them capable of stabilizing a specific LTI process-in such a way that the stability of the closed-loop system is guaranteed for any switching sequence. We show that it is possible to find realizations for any given family of controller transfer matrices so that the closed-loop system remains stable, no matter how we switch among the controller. The motivation for this problem is the control of complex systems where conflicting requirements make a single LTI controller unsuitable.

This paper presents the results of extensive experience in the development and promotion of tobacco-based insecticides for the control of field crop pests in Igalaland, Nigeria. A non-governmental organization (NGO), the Diocesan Development Services (DDS), became involved in the development of tobacco-based insecticides in the early 1990s, and facilitated a series of ‘on-farm’ trials between 1997 and 2000 designed to test the effectiveness of such insecticides for two crops that are particularly vulnerable to pest attack in Igalaland: cowpea (Vigna unguiculata) and maize (Zea mays). The results suggest that even crude tobacco formulations had a significant benefit on cowpea and maize yields relative to the absence of pest control, although commercial insecticides were more effective. However, while having advantages of cost and availability over commercial insecticides, tobacco-based products appear to have serious internal and external disadvantages that limit their widespread use, and some of these are discussed. It is concluded that while technical efficacy of botanicals is an important element, there are others such as the logistics of production and preparation that need to be considered. A better understanding of the balance between these factors and how context-specific they may be is required in order to maximize their adoption by farmers under ‘resource-poor’ conditions.

The subject of this paper is hybrid control of nonlinear systems with large-scale uncertainty. We describe a high-level controller, called a ''supervisor'', which orchestrates logic-based switching among a family of candidate controllers. We show that in this framework, the problem of controller design at the lower level can be reduced to finding an integral-input-to-state stabilizing control law for an appropriate system with disturbance inputs. Employing the recently introduced ''scale-independent hysteresis'' switching logic, we prove that in the case of purely parametric uncertainty with unknown parameters taking values in a finite set the switching terminates in finite time and state regulation is achieved.

This paper describes the results of a six year study based in a village (Eroke) in Igalaland, Nigeria, designed to compare an external vision of agricultural sustainability with internal perspectives. Cropping intensities were high, and change was apparent over the study period, with, for example, a decline in production of maize and an increase in production of cassava and some legumes. From an external perspective many of the indicators pointed towards unsustainability in agriculture, with the main driving force being individual household circumstance, and particularly the availability of labour. Households were dynamic, with constant immigration and emigration of males and females, but all members of the family saw emigration of young males as positive as it adds to ‘household sustainability.’ Agricultural sustainability was seen as negotiable, and often played off against wider concerns of family sustainability. If stakeholder participation is seen as a fundamental human right rather than jus...

The authors regret that Dr Moreno di Marco's name was published with errors in the original abstract. The authors would like to apologise for any inconvenience caused.

In a network of n agents, consensus means that all n agents reach an agreement on a specific value of some quantity via local interactions. A linear consensus process can typically be modeled by a discrete-time linear recursion equation or a continuous-time linear differential equation, whose equilibria include nonzero states of the form a1 where a is a constant and 1 is a column vector in ℝn whose entries all equal 1. Using a suitably defined semi-norm, this paper extends the standard notions of uniform asymptotic stability and exponential stability from linear systems to linear recursions and differential equations of this type. It is shown that these notions are equivalent just as they are for conventional linear systems. The main contributions of this paper are first to provide a simple, direct proof of the necessary graph-theoretic condition given in [1] for a discrete-time linear consensus process to be exponentially stable, and second to derive a necessary graph-theoretic condition for a piecewise time-invariant continuous-time linear consensus process to be exponentially stable.

In [1], given a matrix A and a vector b, a distributed algorithm was proposed for solving linear algebraic equations of the form Ax = b when there is at least one solution. The equation is simultaneously solved by a group of autonomous agents whose neighbor relations are characterized by a time-dependent directed graph. The main contribution of this paper is to provide necessary and sufficient conditions for exponential convergence of the algorithm under the most general assumption. These conditions utilize a new notion of graph connectivity which is less restrictive than strong connectivity.

SUMMARYWhite yam (Dioscorea rotundata) is a major root crop grown throughout West Africa but one of the major factors that limits its production is the availability of good quality planting material. This paper described the results of farmer-managed demonstration plots established in 2012 and 2013 designed to promote the Adapted Yam Minisett Technique (AYMT) in Nigeria. The AYMT was developed between 2005 and 2008 to produce quality seed yam tubers at a cost that is viable for small-scale farmers. Since its development the agronomic performance of AYMT has not been explored across a large sample of farmers, and neither has there been any attempt to explore possible varietal effects although farmers have often alluded to this. This papers seeks to address these gaps in the literature and the results suggest that the AYMT does succeed in producing seed yams of the required size and the economic returns are also good. Results also suggest that there is a varietal affect with AYMT, including a significant interaction with pesticide treatment; the first time this has been demonstrated.

The level of uptake and use of personal protective equipment (PPE) by farm workers in Oman is low; the conditions under which pesticides are stored are frequently below acceptable international standards. Research was undertaken to explore the drivers working against safe storage of agrochemicals and effective personal protection usage by pesticide application personnel. Results from a survey of over 200 respondents, representing workers in, and owners of, farms either within or outside a local farmer's association (FA), suggest that FA membership raises standards of behaviour both in terms of safe pesticide storage and use of PPE. Age of respondents had no apparent effect on the likelihood of PPE (gloves and masks) use. PPE use was, however, highest among respondents with more advanced educational backgrounds. Positive responses for glove and mask use, when applying pesticides, were higher for owners and workers in FA farms compared to non-FA farms. Lowest reported use of PPE was among workers in non-FA farms. Analysis of responses appears to indicate that behaviour patterns of workers in FA farms mirror that of the farm owners. This was not the case in non-FA farms. The results suggest that conformity to social norms, in this case acceptable work-environment behaviour, is a powerful driver behind raised usage levels of PPE in farms in Oman.

In a study of pesticide use on farms in Oman, over 200 respondents were surveyed from amongst owners of and workers on farms that belonged to a Farmers' Association (FA) and those that did not belong to the FA. A questionnaire was used to gauge attitudes to pesticide use whilst inventories of active ingredients were taken for all farms. The age profiles of the respondents were broadly similar, as was the distribution of nationalities amongst the workers. Workers and owners of FA farms were better educated than respondents from non-member farms. A majority of non-FA farm workers reported that they always used pesticides, fewer FA member farm workers and non-FA farm owners reported this behaviour with FA owners showing the lowest proportion of respondents who always used pesticides. Responses amongst farm owners to questions about frequency of pesticide use suggested that this was unaffected by age or education status, but for farm workers younger or less well educated respondents were more likely to respond by indicating that pesticides were always used. When asked to rate pesticides on a scale of 1 (bad) to 10 (good), high responses were most frequent amongst non-FA farm workers followed by FA member farm workers and non-FA farm owners. On average FA farm owners had the lowest average response, and responses by all groups were unaffected by age or education status. Prohibited pesticide use was higher on non-FA farms (4.9% of all pesticides) than on FA farms (1.3%). Pesticide products observed on FA member farms generally contained newer classes of active ingredients and were most frequently from major manufacturing companies in Europe, North America and Japan. Older, off-patent active ingredient-containing products were frequently observed on non-FA farms, often from so-called ‘me-too’ producing companies in Asia, the Middle East and North Africa.

This paper describes some of the insights gained by the authors in the development of an approach for systemic sustainability analysis to arrive at sustainability indicators (SIs) for development. The paper describes the problems of perspective and mindset which such research involves, and the necessity to rethink both the purpose and content of SIs as well as taking into account the perspective of the researcher. The result represents a new perspective on the classification of SIs that serves to highlight one of the central difficulties encountered so far with these tools, namely their limited use in management and the setting of policy. We argue that this is due in large part to the nature of the SI frameworks created to date, even if carried out in a 'participative' mode. The framework itself is representative of a mindset or paradigm of understanding which, when applied as the sole device, we find less than adequate in achieving useful SIs. SIs arising from this mindset tend to be quantitative and exp...

Multiple Model Adaptive Control involves a supervisor switching among one of a finite number of controllers as more is learnt about the plant. Safe Adaptive Control is concerned with ensuring that when the controller is changed in an adaptive control algorithm, the frozen plant-controller combination is never (closed loop) unstable. A controller scheme is proposed that combines these principles and involves a frequency-dependent performance measure based on the Vinnicombe metric. Safe switching is guaranteed to the extent which closed loop transfer function identification is accurate.

This paper studies the notion of output-input stability, which is a variant of the minimum-phase property for general smooth nonlinear control systems. In the spirit of the "input-to-state stability" philosophy, the definition of the new concept requires the state and the input of the system to be bounded by a suitable function of the output and derivatives of the output, modulo a decaying term depending on initial conditions. The class of output-input stable systems includes all affine systems in global normal form whose internal dynamics are input-to-state stable and also all left-invertible linear systems whose transmission zeros have negative real parts. A characterization of output-input stability for SISO systems is given in terms of suitable relative degree and detectability concepts.

SUMMARY This paper addresses the problem of controlling a continuous-time linear system with large modelling errors. We employ an adaptive control algorithm consisting of a family of linear candidate controllers supervised by a high-level switching logic. Methods for constructing such controller families have been discussed in the recent paper by the authors. The present paper concentrates on the switching task in a multiple model context. We describe and compare two di!erent switching logics, and in each case study the behaviour of the resulting closed-loop hybrid system. Copyright 2001 John Wiley & Sons, Ltd.

SUMMARY The purpose of this paper is to marry the two concepts of multiple model adaptive control and safe adaptive control. In its simplest form, multiple model adaptive control involves a supervisor switching among one of a "nite number of controllers as more is learnt about the plant, until one of the controllers is "nally selected and remains unchanged. Safe adaptive control is concerned with ensuring that when the controller is changed in an adaptive control algorithm, the frozen plant}controller combination is never (closed-loop) unstable. This is a non-trivial task since by de"nition of an adaptive control problem, the plant is not fully known. The proposed solution method involves a frequency-dependent performance measure and employs the Vinnicombe metric. The resulting safe switching guarantees depend on the extent to which a closed-loop transfer function can be accurately identi"ed. Copyright 2001 John Wiley & Sons, Ltd.

Sustainability indicators (SIs) are increasingly seen as important tools in the implementation of sustainable development. Numerous suggested SI lists and matrices exist, but a remaining problem is how these diverse SIs are to be integrated into an answer as to whether something is sustainable or not. In some studies of sustainability workers have adopted a quantitative integration approach whereby SIs are given numerical values and integrated mathematically to produce a value for sustainability. In this paper the authors discuss SI integration by drawing upon the results of a six-year research project based in a village in Nigeria. They conclude that an element of'qualitative integration' incorporating value judgements and subjectivity is inevitable with a concept such as sustainability, even if one begins with what may seem like sharp and quantitative SIs. It is argued that SIs are primarily a product of development intervention rather than a desire to understand, and as a result carry with them the desired characteristics, from the donor perspective, of efficiency and accountability. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment

and public concerns due to accounts in the popular press of killer germs. 7 The initial activities were aimed at regulation of biological agent transfers and training emergency responders in 120 cities—commonly referred to as the Nunn-Lugar-Domenici preparedness programme—and was aimed at overt chemical terrorism. 8,9 This focus has expanded to acknowledge and address the key role that public health will have in detection and management of a covert biological terrorist incident. Similar efforts to coordinate national contingency arrangements and successfully conclude negotiations over the protocol for verification of the Biological Weapons Convention are underway in the UK. 9

This paper explores the fundamental limits of the use of quartz tuning forks as force detectors in scanned probe microscopy. It is demonstrated that at room temperature, pressure, and atmosphere these force sensors have a noise floor of 0.62 pN/Hz and exhibit a root mean square Brownian motion of only 0.32 pm. When operated as a shear force sensor both dissipative and reactive forces are detected on approach to the sample. These forces are sufficient to reduce the amplitude of motion of the probe nearly to zero without physically contacting the surface. It is also demonstrated that conventional proportional-integral feedback control yields closed loop responses at least 40 times faster than their open loop response.

A number of studies have explored the relationship between uncertainty and savings behaviour amongst resource-poor farmers. This paper describes the results of such a study for five villages in the Ibaji area of Igalaland, Kogi State, Nigeria. Savings behaviour over a 20-year period was examined in the face of two severe types of shock: flooding and land war. The results suggest that although the macroeconomic climate in Nigeria could explain some general trends in savings behaviour, some clear peaks in activity were not due to shocks but to operational changes introduced by the non-government organization facilitating the savings scheme—the Diocesan Development Services (DDS). The results suggest that great care needs to be taken when interpreting such time-series data, especially as one peak in savings activity corresponded with the period of the land war. Copyright © 2000 John Wiley & Sons, Ltd.

Yam rots caused by fungal pathogens (mostly Fusarium spp.) are a major cause of storage losses, and previous work has shown that fungal lesions were only found if there was pre-existing physical damage to the tuber. The general perception is that damage inflicted in the field prior to storage is far more important in this regard than damage caused during storage, and this has led to much research directed at the minimisation of field damage with relatively little work on the amelioration of insect damage during storage. This study examined whether insect damage inflicted on yam tubers during storage in specialised barns is an important agent in the incidence of fungal disease. It was found that treatment of tubers with insecticide dust (Actellic 2% Dust; ai=pirimiphos-methyl) significantly reduced fungal infections resulting from insect attack during storage. In addition, physical damage acquired during harvest appeared to be ameliorated by the insecticide, resulting in significantly fewer fungal lesions. The results suggest that insecticide treatment of yam tubers prior to storage could provide a relatively cheap and effective means of preservation.

This paper is concerned with control of nonholonomic systems in the presence of parametric modeling uncertainty. The specific problem considered is that of parking a wheeled mobile robot of unicycle type with unknown parameters, whose kinematics can be described by Brockett's nonholonomic integrator after an appropriate state and control coordinate transformation. We employ the techniques of supervisory control to design a hybrid feedback control law that solves this problem.

We present a sucient condition for asymptotic stability of a switched linear system in terms of the Lie algebra generated by the individual matrices. Namely, if this Lie algebra is solvable, then the switched system is exponentially stable for arbitrary switching. In fact, we show that any family of linear systems satisfying this condition possesses a quadratic common Lyapunov function. We also discuss the implications of this result for switched nonlinear systems. c 1999 Elsevier Science B.V. All rights reserved.

This paper explains how to stabilize a ''nonholonomic integrator'' using a hybrid control law employing switching and logic. Results concerning asymptotic stability and exponential convergence to the origin are derived. The notion of a (positively) invariant set is extended to hybrid systems and sufficient conditions for invariance are presented. The verification of these conditions does not require the computation of the state trajectories and their use goes beyond the analysis of the system presented in this paper.

We present a brief introduction to the five articles that make up this special issue: Shock Graphs and Shape Matching, The Bas-Relief Ambiguity, Incremental Focus of Attention for Robust Vision Based Tracking, What Tasks can be Performed with an Uncalibrated Stereo Vision System, and Volumetric Deformation Analysis Using Mechanics-Based Data Fusion: Application in Cardiac Motion Recovery. Tjis introduction and accompanying articles provide a by no means exhaustive, but hopefully representative sampling of the computational vision at Yale University.

This paper describes soil N and P balances calculated at field and farm level in Kindo Koisha, southern Ethiopia. The balances were calculated for eight farms representing two agro-ecological zones (highland and lowland) and four socio-economic farmer groups (rich, medium, poor and very poor). Processes quantified included mineral fertilizer, organic matter, deposition, N fixation (inputs) and harvested products, removed residues, leaching, denitrification and water erosion (outputs). Measurements of N and P flows were made in the four major farm components: enset-garden, darkoa, taro root and shoka fields. Field scale analysis showed that N and P balances were either in equilibrium or positive in most of the farm components across all farms, suggesting that soil fertility is being maintained or even increasing. However, the shoka field, one of the most important components in terms of contribution to total farm output, had strongly negative N balances in all farms. P balances were mostly positive although slight deficits were occasionally observed. The aggregated farm scale balances varied considerably across socio-economic groups and agro-ecological zones. N depletion was severe for rich farmers in the highland and for poor farmers in the lowland. Differences in N and P balances were also observed between agro-ecological zones. There is a need for a more targeted approach to soil fertility intervention that differentiates between farm component, agro-ecological zone and socio-economic group.

summary The article discusses some of the issues surrounding sustainability in the provision of financial services by the Diocesan Development Services (DDS) in Nigeria. The article describes the history and growth of DDS within the turbulent social, economic and political conditions in Nigeria, and examines (i) to what extent financial sustainability is an achievable goal for DDS, and (ii) whether donors should play a pro‐active role in influencing local decisions. The article analyses the problems faced by DDS when a major donor tried to push it to attain rapidly financial sustainability.

Despite its theoretical prominence and sound principles, integrated pest management (IPM) continues to suffer from anemic adoption rates in developing countries. To shed light on the reasons, we surveyed the opinions of a large and diverse pool of IPM professionals and practitioners from 96 countries by using structured concept mapping.\ud The first phase of this method elicited 413 open-ended responses on perceived obstacles to IPM. Analysis of responses revealed 51 unique statements on obstacles, the most frequent of which was “insufficient training and technical support to farmers.” Cluster analyses, based on participant opinions, grouped these unique statements into six themes: research weaknesses, outreach weaknesses, IPM weaknesses, farmer weaknesses, pesticide industry interference, and weak adoption incentives. Subsequently, 163 participants rated the obstacles expressed in the 51 unique statements according to importance and remediation difficulty. Respondents from developing countries and high-income countries rated the obstacles differently. As a group, developing-country respondents rated “IPM requires collective action within a farming community” as their top obstacle to IPM adoption. Respondents from high-income countries prioritized instead the “shortage of well-qualified IPM experts and extensionists.” Differential prioritization was also evident among developing-country regions, and when obstacle statements were grouped into themes. Results highlighted the need to improve the participation of stakeholders from developing countries in the IPM adoption debate, and also to situate the debate within specific regional contexts.

With a unique cultural background and fast economic development, China’s adoption of corporate social responsibility (CSR) has become the center of discussion worldwide, and its successful implementation will have great significance for global sustainability. This paper aims to explore how CSR has given way to economic growth in China since the start of economic transition and its cultural, historical and political background, and how this has affected or been affected by the economic performance of firms. Thus, the recent calls for China to adopt CSR in its industries follow a period where the country arguably had one of the strongest implementations of CSR approaches in the world. This transition is considered in the context of a case study of a Chinese state-owned enterprise (SOE) and a group of small private firms in the same industrial sector in Zhengzhou City, Henan Province over a time span of eight years. While the CSR of the SOE has been steadily decreasing along with the change of ownership structure, its economic performance did not improve as expected. On the other hand, with a steady improvement in economic performance, the small private firms are showing a great reluctance to engage in CSR. The results indicate that implementation of CSR in China needs both the manager’s ethical awareness and the change of institutional framework. The results also raise the question as to whether CSR is a universal concept with a desired means of implementation across the developed and developing world.

Groupthink is a known weakness leading to a number of problems relating primarily to false senses of consensus. But, positive group 'wisdom' is an ideal which many aspire to make happen but few manage to achieve in practice. The mystery of the group comes at a number of levels and raises various issues. What is the relative importance of how groups assemble? How they are motivated? The value of inducement? How can group work be assessed and how is a 'good' group identified? How is positive and not negative group working achieved? How is group working linked to what the group achieves? In the area of policy use of indicators the function of the group becomes more critical. In an age of transparency in decision making and calls for more evidence-based policy, the importance of good group work is becoming vital if the project is to succeed. Based on research undertaken around the European Union between 2009 and 2010 this paper explores some of these questions by providing a series of 'rich pictures' of indicator use, the meanings ascribed to the pictures by the group members and some insights regarding the dynamics of the groups that rest behind them and how this may have influenced the stories told by the pictures. We argue that in many ways the pictures represent a window to the understanding of the groups use of indicators. © 2013 Elsevier Ltd. All rights reserved.

A distributed algorithm is described for solving a linear algebraic equation of the form Ax = b where A is a matrix for which the equation has at least one solution. The equation is simultaneously and asynchronously solved by m agents assuming each agent knows only a subset of the rows of the partitioned matrix [A b], the estimates of the equation's solution generated by its neighbors, and nothing more. Each agent recursively updates its estimate of a solution at its own event times by utilizing estimates generated by each of its neighbors which are transmitted with delays. Each agent has its own event time sequence and the event time sequences of different agents are not assumed to be synchronized. Neighbor relations are characterized by a time-dependent directed graph whose vertices correspond to agents and whose arcs depict neighbor relations. It is shown that for any matrix A for which the equation has a solution and any repeatedly jointly strongly connected sequence of neighbor graphs defined on the merged sequence of all agents' event times, the algorithm causes all agents' estimates to converge exponentially fast to the same solution to Ax = b.

Gradient control laws can be used for effectively achieving undirected formation shape, by assuming that interagent distances between a certain set of joint agent pairs can be accurately specified and measured. This paper examines the formation behavior in a 3-D space context in the case that the neighboring agent pairs have slightly differing views or estimates about the desired interagent distances they are tasked to maintain. It is shown, by using a tetrahedron formation example, that the final formation shape will be slightly distorted as compared to the desired one. Further, in general each agent's motion will be a combination of rotation and translation. Specifically, a helical movement can be observed in the presence of distance mismatch.

In this study, four commonly-used sampling devices (vacuum socks, 37 mm 0.8 μm mixed cellulose ester (MCE) filter cassettes, 37 mm 0.3 μm polytetrafluoroethylene (PTFE) filter cassettes, and 3M™ forensic filters) were comparatively evaluated for their ability to recover surface-associated spores. Aerosolized spores (~ 10 5 CFU cm − 2 ) of a Bacillus anthracis surrogate were allowed to settle onto three material types (concrete, carpet, and upholstery). Ten replicate samples were collected using each vacuum method, from each material type. Stainless steel surfaces, inoculated simultaneously with test materials, were sampled with pre-moistened wipes. Wipe recoveries were utilized to normalize vacuum-based recoveries across trials. Recovery (CFU cm − 2 ) and relative recovery (vacuum recovery/wipe recovery) were determined for each method and material type. Recoveries and relative recoveries ranged from 3.8 × 10 3 to 7.4 × 10 4 CFU cm − 2 and 0.035 to 1.242, respectively. ANOVA results indicated that the 37 mm MCE method exhibited higher relative recoveries than the other methods when used for sampling concrete or upholstery. While the vacuum sock resulted in the highest relative recoveries on carpet, no statistically significant difference was detected. The results of this study may be used to guide selection of sampling approaches following biological contamination incidents.

The objective of this study was to compare an extraction-based sampling method to two vacuum-based sampling methods (vacuum sock and 37 mm cassette filter) with regards to their ability to recover Bacillus atrophaeus spores (surrogate for Bacillus anthracis) from pleated heating, ventilation, and air conditioning (HVAC) filters that are typically found in commercial and residential buildings. Electrostatic and mechanical HVAC filters were tested, both without and after loading with dust to 50% of their total holding capacity. The results were analyzed by one-way ANOVA across material types, presence or absence of dust, and sampling device. The extraction method gave higher relative recoveries than the two vacuum methods evaluated (p ≤ 0.001). On average, recoveries obtained by the vacuum methods were about 30% of those achieved by the extraction method. Relative recoveries between the two vacuum methods were not significantly different (p > 0.05). Although extraction methods yielded higher recoveries than vacuum methods, either HVAC filter sampling approach may provide a rapid and inexpensive mechanism for understanding the extent of contamination following a wide-area biological release incident.