A Genetic Algorithm solver for pest management control in Island systems

Island conservation management is a truly multidisciplinary problem that requires considerable knowledge of the characteristics of the ecosystem, species and their interactions. Nevertheless, this can be translated into an optimisation problem. Essentially, within a limited budget, a manager needs to select the conservation actions according to expected payoffs (in terms of protecting or restoring desired species) versus cost (the amount of resources/money) required for the actions. This paper presents the problem in terms of a knapsack formulation and develops optimisation techniques to solve it. From this, decision-support software is being developed, tailored to meet the needs of pest control on islands for conservation managers. The solver uses a Genetic Algorithm and incorporates a simplified model of the problem. The solver derives strategies that reduce the number of threats, allowing the preservation of desired species. However, the problem model needs further refinement to derive truly realistic options for conservation managers

The co-ordinative practices of temporary organisations

Purpose: This paper aims to explore the necessary mechanisms for coordination in complex industrial networks which are temporary in nature, known as temporary organisations (TOs). Design/methodology/approach: The paper is based on two in-depth case studies conducted in the UK construction industry. Findings: The paper outlines the necessary mechanisms for coordination in TOs – referred to as “scaffolding practices” – which ensure consistency(stability in terms of thinking and action), consensus (agreement) and co-constitutiveness (personal pledges and commitments). Research limitations/implications: The study provides practical implications for situations where actors create temporary organisational specific logics. This “logic” helps explain how actors are able to undertake tasks of finite duration where members lack familiarity and have competing loyalties. Originality/value: The paper is novel in that it represents the first extant attempt to examine “temporary industrial organizations” where individuals from different (often competing) organisations collaborate on a task for a defined period and suggests how coordination may be achieved

Contagion and learning in business networks

The purpose of this study is to examine network learning through the application of contagion theories. The transmission of knowledge, sharing of resources, and facilitation of learning through contagion has interested both business-to-business and economic geography researchers. This study responds to calls in both research traditions for research into knowledge and learning at the level of an interfirm network. More specifically, it focuses on developing an understanding of how the contagion of knowledge and ideas and the co-ordination of activities within a network tales place. We achieve this by drawing upon research in both network relationships dynamics and learning processes to investigate the causal mechanisms that drive contagion. We focus on two types of contagion: contagion by cohesion (i.e. the presences and closeness of direct contact with others in the network), and contagion by structural equivalence (i.e. where influence is related to the structural patterns of relationships in the network). We also identify two key mechanisms that act as a barrier to such contagion: isolation and immunity. We explore the implications of these findings for network learning opportunities, specifically learning-by-doing, learning-by-using, and learning-by-interacting

Optimality In Reserve Selection Algorithms: When Does It Matter And How Much?

This paper responds to recent criticisms in Biological Conservation of heuristic reserve selection algorithms. These criticisms primarily concern the fact that heuristic algorithms cannot guarantee an optimal solution to the problem of representing a group of targeted natural features in a subset of the sites in a region. We discuss optimality in the context of a range of needs for conservation planning. We point out that classical integer linear programming methods that guarantee an optimal solution, like branch and bound algorithms, are currently intractable for many realistic problems. We also show that heuristics have practical advantages over classical methods and that suboptimality is not necessarily a disadvantage for many real-world applications. Further work on alternative reserve selection algorithms is certainly needed, but the necessary criteria for assessing their utility must be broader than mathematical optimality

Towards a typology of collusive industrial networks:dark and shadow networks

The prevailing understanding of collusive B2B networks is primarily based on the theories of industrial economists and organizational criminologists. ‘Successful’ collusive industrial networks (such as price-fixing cartels) have been seen to endure due to formal managerial structures of coordination and control. In this paper, we seek to transcend and challenge the understanding of these illegal forms of co-opetition by drawing on evidence from an in-depth examination of four price-fixing cartels that were facilitated chiefly by marketers. Our contribution introduces the notion of ‘shadow networks’ (networks where although attempts are made to ensure secrecy, multilateral modes of network structure dominate akin to ‘normal’ managerial endeavours such as joint ventures) and ‘dark networks’ (networks which appear more opaque and secretive through the adoption of bilateral modes of network structure and limited bureaucracy) to illustrate the types of collusive network forms that may exist. In addition, this allows us to build a deeper understanding of collusive network forms and related inter-firm interaction for an industrial marketing audience. We provide implications for marketing practice, theory, and policy. Specifically, we outline how organizations and the marketing function can perform self-administered antitrust audits in order to help avoid breaches of antitrust. Further, we consider the importance of the two forms of collusive inter-firm networks uncovered where marketers have attempted to render these secret from antitrust agencies, introducing a relatively new line of inquiry to the industrial marketing literature

Sucrose protects cell wall invertase but not vacuolar invertase against proteinaceous inhibitors

AbstractVacuolar (VI) and cell wall invertases (CWI) of higher plants can be inactivated in vitro and, possibly, in vivo by proteinaceous inhibitors. The respective mechanisms have not yet been compared. Therefore, partially purified CWI from transformed tobacco cells and VI from tomato fruit were preincubated with invertase-inhibitor fractions isolated from the same tissues. Both inhibitors were able to inhibit both invertases. However, VI was fully inhibited within less than 1 min by both inhibitors, whereas inactivation of CWI was much slower. Furthermore, CWI, but not VI, was strongly protected against inhibition by sucrose. A polyclonal antiserum directed against the tobacco inhibitor (INT) cross-reacted with a 19 kDa polypeptide in the partially purified tomato inhibitor (ILE) fraction. The results indicate that INT and ILE have similar structural properties, whereas the mechanism of inactivation is clearly different for CWI and VI

Effectiveness Of Alternative Heuristic Algorithms For Identifying Indicative Minimum Requirements For Conservation Reserves

We compared the results of 30 heuristic reserve selection algorithms on the same large data set. Twelve of the algorithms were for presence-absence representation goals, designed to find a set of sites to represent all the land types in the study region at least once. Eighteen algorithms were intended to represent a minimum percentage of the total area of each land type. We varied the rules of the algorithms systematically to find the influence of individual rules or sequences of rules on efficiency of representation. Rankings of the algorithms according to relative numbers or areas of selected sites needed to achieve a specified representation target varied between the full data set and a subset and so appear to be data-dependent. We also ran optimizing algorithms to indicate the degree of suboptimality of the heuristics. For the presence-absence problems, the optimizing algorithms had the advantage of guaranteeing an optimal solution but had much longer running times than the heuristics. They showed that the solutions from good heuristics were 5-10% larger than optimal. The optimizing algorithms failed to solve the proportional area problems, although heuristics solved them quickly. Both heuristics and optimizing algorithms have important roles to play in conservation planning. The choice of method will depend on the size of data sets, the representation goal, the required time for analysis, and the importance of a guaranteed optimal solution

Gone with the forest: Assessing global woodpecker conservation from land use patterns

As a result of their ecological traits, woodpeckers (Picidae, Aves) are highly sensitive to forest cover change. We explored the current land cover in areas of high species richness of woodpeckers to determinate regions where urgent conservation actions are needed. In addition, we identified woodpecker species that are sensitive to forest loss and that have high levels of human habitat modification and low levels of protection (through protected areas) in their distribution ranges. Location: Global. Methods: We joined available range maps for all extant 254 woodpecker species with information of their conservation status and tolerances to human habitat modifications and generated a richness map of woodpecker species worldwide. Then, we associated this information (the richness pattern and individual species’ maps) with land cover and protected areas (PAs) maps. We found that the foremost woodpecker species richness hotspot is in Southeast Asia and is highly modified. At the second species richness hotspot in the eastern Andes, we observed a front of deforestation at its southern extreme and a greater deforested area in its northern extreme but most of its area remains with forest coverage. At the species level, 17 species that are sensitive to forest modification experience extensive deforestation and have low extents of PAs in their ranges.The most diverse woodpecker hotspots are mostly occupied by human-modified landscapes, and a large portion of the species there avoids anthropogenic environments. The level of representation of woodpecker species in PAs is low as a global general pattern, although slightly better in Asia. Our global analysis of threats to woodpecker from land use patterns reiterates the urgent conservation needs for Southeast Asian forests. Finally, based on our results, we recommend a re-evaluation for inclusion in the Red List of five woodpecker species.Fil: Vergara Tabares, David Lautaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; ArgentinaFil: Lammertink, J. Martjan. Cornell University; Estados Unidos. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Verga, Ernesto Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Schaaf, Alejandro Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Jujuy. Universidad Nacional de Jujuy. Centro de Investigaciones y Transferencia de Jujuy; ArgentinaFil: Nori, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentin

What is the extent and distribution of evidence on effectiveness of systematic conservation planning around the globe? A systematic map protocol

Background: Systematic conservation planning involves the prioritisation of conservation actions to optimise biodiversity conservation outcomes whilst considering implementation challenges such as minimising costs. Thousands of systematic conservation plans have been developed around the globe (a popular software package, 'Marxan', has over 4200 active users from more than 180 countries). However, the effects of systematic approaches on conservation actions and outcomes are not generally known, nor are the factors which distinguish effective from ineffective plans. Previous reviews of conservation planning outcomes have been limited in scope and to narrow time intervals, and have revealed very few formal evaluations of plans. Given systematic approaches are widely perceived to offer the best chance to rapidly and efficiently achieve biodiversity protection targets, a thorough, up-to-date synthesis of the evidence is required. Methods: This protocol outlines the methodology for a systematic mapping exercise to identify retrospective studies measuring the effects of systematic conservation planning on biodiversity conservation at regional, national and subnational scales. Our primary research question is: what is the extent and distribution of evidence on the conservation outcomes of systematic conservation planning? Outcomes will be categorised according to types of capital: natural, financial, social, human and institutional, given the range of potential direct and indirect effects of systematic conservation planning on conservation outcomes. A comprehensive and repeatable search strategy will be undertaken, utilising a wide range of sources including grey literature sources and targeted searches of organisational websites and databases. Sources will be restricted to English language publications between 1983 and 2016. The resultant studies will be screened using standardised inclusion and exclusion criteria and data from included studies will be categorised according to a standardised data extraction form. Information about the study design of relevant articles will be recorded to determine study robustness. A searchable database of studies will be made publicly accessible and available for updating in future. The results will be published in this journal and also presented as an interactive online resource to aid conservation planners in identifying impacts and outcomes of conservation plans

Involving customers in innovation: knowledgeability and agency as process variables

Purpose: Recent research places an increased emphasis on the inclusion of the customer in value creation, learning, and innovation processes yet there remains a gap in our understanding of just how such customer involvement may work. This paper seeks to address this gap by examining two aspects of customer involvement; their knowledgeability and their agency. In addition, we explore three boundaries (semantic, syntactic, and pragmatic) across which relationship development occurs and which mayfacilitate and/or inhibit value co-creation, collaborative learning, and innovation processes. Design/methodology/approach: We utilised three case studies. Two were large scale construction projects in the UK, and one was a global professional accounting firm in the USA. Findings: Customers may become frustrated if not allowed to exercise their agency. However, their involvement can create tensions for suppliers who may have to become more tolerant of divergent goals. In respect of knowledgeability, we found that constraint satisfaction is important in allowing customers to reconcile their personal knowledge schema with that of the collective schema. However, we also noted that customer knowledgeability brings with it challenges for suppliers, who must find ways to add value for such customers. Research implications: We pose a number of further questions relating to the agency and knowledgeability of customers and their inclusion in value co-creation, collaborative learning, and innovation processes. We also highlight the need for guidance in identifying and minimising the barriers to crossing semantic, syntactic and pragmatic boundaries between customers and suppliers. Originality/value: We make an important contribution to research in the field in that we investigate how the inclusion of the customer in business networksalters current assumptions and practices