68,968 research outputs found
Dynamics of Network Formation Processes in the Co-Author Model
No full textThis article studies the dynamics in the formation processes of a mutual consent network in game theory setting: the Co-Author Model. In this article, a limited observation is applied and analytical results are derived. Then, 2 parameters are varied: the number of individuals in the network and the initial probability of the links in the network in its initial state. A simulation result shows a finding that is consistent with an analytical result for a state of equilibrium while it also shows different possible equilibria.Dynamics, Network, Game Theory, Model,Simulation, Equilibrium, Complexity
Interplay between network configurations and network governance mechanisms in supply networks a systematic literature review
No full textPurpose: This work systematically reviews the extant academic management literature on supply networks. It specifically examines how network configurations and network governance mechanisms influence each other in supply networks.
Design: 125 analytical and empirical studies were identified using an evidence-based approach to review the literature mainly published between 1985 and 2012.
Synthesis: Drawing on a multi-disciplinary theoretical foundation, this work develops an integrative framework to identify three distinct yet interdependent themes that characterize the study of supply networks: a) Network Configurations (structures and relationships); b) Network Governance Mechanisms (formal and informal); and c) The Interplay between Network Configurations and Network Governance Mechanisms.
Findings: Network configurations and network governance mechanisms mutually influence each other and cannot be considered in isolation. Formal and informal governance mechanisms provide better control when used as complements rather than as substitutes. The choice of governance mechanism depends on the nature of exchange; role of management; desired level of control; level of flexibility in formal contracts; and complementary role of formal and informal governance mechanism.
Research implications: This nascent field has thematic and methodological research opportunities for academics. Comparative network analysis using longitudinal case studies offers a rich area for further study.
Practical Implications: The complexity surrounding the conflicting roles of managers at the organisation and network levels poses a significant challenge during the development and implementation stage of strategic network policies.
Originality/value: This review reveals that formal and informal governance mechanisms provide better control when used as complements rather than as substitutes
author-bios-SRD-19-0063.R1 – Supplemental material for The Network Structure of Police Misconduct
No full textSupplemental material, author-bios-SRD-19-0063.R1 for The Network Structure of Police Misconduct by George Wood, Daria Roithmayr and Andrew V. Papachristos in Socius</p
Potato diversity at height: multiple dimensions of farmer-driven in-situ conservation in the Andes
No full textIn-situ conservation Two types of in-situ conservation of crop genetic resources can be distinguished: farmer-driven and externally driven. The first is subject of this thesis and refers to the persistence of potato genetic resources in areas where everyday practices of farmers maintain diversity on-farm. The second concerns the more recent phenomenon of Research & Development (R&D) interventions which aim to support in-situ conservation by farmers. In this study, farmer-driven in-situ conservation of the potato in the central Andes of Peru is investigated at different system levels from alleles, cultivars, and botanical species up to the level of the landscape, as well as the interconnected seed and food systems. Dimensions of time and space are inferred upon by taking both annual and longer-term spatial patterns into account. Further, diversity is linked to selected farmer-based and external drivers. Objective and study area The overall objective of the study is to enhance our understanding of farmer-driven in-situ conservation and the context in which it takes place. The main field research was conducted between 2003 and 2006 in eight farmer communities following a north-south transect through the department of Huancavelica. Communities were selected on the basis of distribution and distance along the north-south transect, tradition of potato cultivation, ethnicity, and relative distance from major markets or cities. Depending on the specific dimension of farmer-driven in-situ conservation investigated, a range of different methods and tools were used. Chapter 1 provides a brief description of the study area and an overview of the research methods used. Species, cultivar and allelic diversity In chapter 2 the species, morphological and molecular diversity of Andean potatoes in Huancavelica is treated at different scales of conservation: farmer family, community, geographically distanced, regional, in-situ and ex-situ subpopulations. The infraspecific diversity of in-situ collections was characterized using morphological descriptor lists and 18 polymorphic microsatellite markers (SSR). Botanical species were determined through ploidy counts in combination with morphological keys. Datasets were used for descriptive statistics, (dis)similarity analysis, dendrogram construction, cophenetic analysis, matrix correlations calculations (Mantel tests), and Analysis of Molecular Variance (AMOVA). Results show that farmers in Huancavelica maintain high levels of species, morphological and molecular diversity. All cultivated potato species with the exception of Solanum phureja and Solanum ajanhuiri proved to be present. Tetraploid species were most abundant followed by diploids, triploids and pentaploids. A total of 557 morphologically unique cultivars were identified based on the morphological characterization of 2,481 accessions belonging to 38 in-situ collections. Genetic fingerprinting of 989 accessions belonging to 8 in-situ collections resulted in the identification of 406 genetically unique cultivars. AMOVA shows that the principal source of molecular variation is found within rather than between geographically distanced and farmer family subpopulations. No evidence of genetic erosion was found as the contemporary regional in-situ population and a geographically restricted subset of CIP´s ex-situ core collection share 98.8% of allelic diversity. Yet, in-situ collections contain numerous unique genotypes. Indigenous biosystematics The indigenous biosystematics of potatoes (folk taxonomy, folk descriptors and nomenclature) is investigated in chapter 3. The chapter includes an extensive literature review on the subject. Folk taxonomy was investigated with the use of grouping exercises with farmers, participant observation, and comparison of farmer-recognized groups with formal classification based on morphological descriptors and 18 polymorphic microsatellite markers (SSR). Analysis of the latter was based on (dis)similarity analysis, dendrogram construction and consequent levels of coherent clustering by folk taxonomic entity (folk specific and varietal taxon). Ethnobotanical free and indicated listing exercises with farmers were used for research concerning folk descriptors. Descriptive statistics were used for analysis and interpretation. Nomenclature was investigated by applying nomenclature surveys, participant observation and basic ethnolinguistic analysis of regional names. Folk taxonomy of the potato consists of no less than five ranks. The folk generic rank is composed of three taxa: Araq Papa (semi-wild / consumed), Papa Tarpuy (cultivated / consumed), and Atoq Papa (wild / not consumed). Folk specific taxa (= cultivar groups) and varietal taxa (= cultivars) within the generic taxon of Papa Tarpuy are abundant. Use categories and agroecological criteria are of little importance in the folk taxonomical system of the potato. Folk varietal taxa cluster well when using formal morphological descriptors; folk specific taxa less so. A moderate concordance, albeit with considerable exceptions, exists between folk specific or varietal taxa and their genetic make-up as characterized with molecular markers (18 SSR microsatellites). The coherence of clustering in a dissimilarity tree varies for each folk specific or varietal taxon considered. Farmers use 22 plant and 15 tuber folk descriptors with recognized character states in the Quechua language. Farmers are well able to recognize specific cultivars based on aboveground plant parts only (without exposing tubers). Nomenclature is regionally consistent for common cultivars, while inconsistent for scarce cultivars. Primary cultivar names (nouns) generally refer to a folk specific taxon through predominant metaphorical reference to tuber shape. Secondary cultivar names (adjectives) predominantly provide direct reference to tuber color. Annual spatial patterns Annual spatial management of the potato consists of cropping and labor calendars, field scattering practices, and genotype by environmental management. These three dimensions of agrobiodiversity management are explored in chapter 4. A structured survey was conducted to investigate the potato cropping and labor calendars. Participatory cartography resulted in the detailed mapping of 601 scattered potato fields, including their cultivar content, belonging to a total of 122 households. A genotype by environment (GxE) experiment employing 4 environments and 31 cultivars was conducted following an altitudinal transect. Data obtained was analyzed and interpreted using descriptive statistics, correlation analysis, Geographical Information Systems (GIS), Additive main Effects and Multiplicative Interaction (AMMI) analysis, and analysis of variance (ANOVA). The annual distribution of tasks and labor is primarily an adaptation to the single-season rain-fed character and climate extremes of high-altitude agriculture. Three different footplough-based tillage systems allow farmers to efficiently manage scarce labor availability for soil preparation. Native-floury, nativebitter and improved potato cultivars show considerable overlap concerning their altitudinal distribution patterns. The notion that these cultivar categories occupy separate production spaces (so-called “altitudinal belts”) is rejected as results show that differences between the altitudinal medians for areal distribution by altitude of the different cultivar categories are modest (chapter 4). Field scattering is based on a combined logic which results in a patchy distribution of potato genetic diversity across the agricultural landscape. Depending on the community, farmers annually crop an average of 3.2 to 9.1 potato fields measuring between 660 to 1,576 m² and containing up to a hundred cultivars per field. However, neither field scattering nor the management of high levels of diversity by farmers is a direct consequence of niche adaptation as most cultivars are versatile (chapter 4). Rather, it is suggested that farmers conduct annual spatial management by deploying combined tolerance and resistance traits imbedded in particular cultivar combinations in order to confront the predominant biotic and abiotic stresses present in different agroecologies. Andean farmers manage GxE adaptation for overall yield stability rather than fine-grained environmental adaptation of native cultivars. Dimensions of land use Three specific dimensions of potato land use were researched in order to gain insights into possible contemporary changes affecting the in-situ conservation of potato genetic resources: land use tendencies, rotation designs and their intensity, and sectoral fallowing systems (chapter 5). The main research method involved participatory cartography using printed poster-size high-resolution Quickbird satellite images combined with in-depth consultation through interviews and focus group meetings with members of the communities. A total of 4,343 fields and their 1995-2005 crop contents were mapped. The evolution over a 30-year time-span (1975-2005) of traditional sectoral fallow systems (“diversity hotspots”) was documented for each community. Data was analyzed using descriptive statistics and Geographical Information Systems (GIS). Processes of change and adaptive innovation were documented by building case studies. Land use tendencies between 1995 and 2005 shows that the total cropping area dedicated to improved cultivars has grown fast while the area dedicated to native-floury and native-bitter cultivars has remained more or less stable. Reduced fallow periods for existing fields and the gradual incorporating of high-altitude virgin pasture lands sustain areal growth. Areal growth is particularly fast at extreme altitudes between 3,900 and 4,350 m. However, fallow periods at these altitudes are still relatively long compared to fields at lower altitudes. Results show that fallowing rates increase by altitude for all cultivar categories, but tend to be lowest for improved cultivars followed by native-floury and native-bitter cultivars. There is no evidence of a straightforward replacement of one cultivar category by another resulting in the replacement and loss of infraspecific diversity. Inquiry into the dynamics of sectoral fallow systems over a 30 year period evidences the gradual disintegration and abandonment of these systems rich in cultivar diversity. They are replaced by more individualist management regimes based on household decision making. Nowadays, the spatial patterning of potato genetic diversity within the agricultural landscape is increasingly characterized by patchy distribution patterns rather than its concentration within a single communal sector. Where sectoral rotation designs survive local innovations have been adopted. Farmer seed systems Farmer seed systems can be conceived as an overlay of crop genetic diversity determining its temporal and spatial patterning. Chapter 6 investigates the relation between selected farmer seed system components (storage, health and procurement) and infraspecific diversity of potato in Huancavelica. A sampling exercise was carried out in farmer seed stores in order to gain insight into the internal organization of seed stores and how this relates to the management of infraspecific diversity. Virus infection rates were determined by taking seed tuber samples of diverse cultivars from farmer’s storage facilities. ELISA tests were conduced for APMoV, PLRV, PMTV, PVY and PVX. Seed procurement was investigated through a series of structured surveys focusing on household seed exchange, the role of regular markets and biodiversity seed fairs, and seed provision after severe regional frost. Data was analyzed and interpreted using descriptive statistics. Potato seed stores contain different seed lots, reflecting the rationales underlying management of cultivar diversity at the field level and the overall structure of infraspecific diversity. Seed health of farmer conserved cultivar stocks in Huancavelica is affected by Diabrotica leaf beetle and contact transmitted viruses (APMoV, PVX) while aphid and powdery scab transmitted viruses (PMTV, PLRV, PVY) are of limited importance. During normal years without extreme events seed exchange of native-floury cultivars is practiced by few households and characterized by a limited number of transactions involving small quantities of seed of few cultivars covering relatively short distances. Native-bitter and uncommon nativefloury cultivars are rarely exchanged and generally reproduced year after year by the same households that maintain them. High-altitude diversity-rich communities tend to be net seed exporters. However, the capacity of the farmer seed system to annually widely supply and distribute infraspecific diversity is limited. Regular markets have a decentralized capacity to supply and widely distribute seed of a limited number of well-known cultivars. Frequencies of seed exchange at biodiversity seed fairs are low and involve small quantities of a few uncommon cultivars. The resilience of the farmer seed system to cope with severe regional seed stress is insufficient for households to be able to restore volumes and cultivar portfolios within a short period of time. The potato-based food system The role of biodiverse potatoes within the human diet in Huancavelica is investigated in chapter 7. Analysis to determine the dry matter, gross energy, crude protein, iron (Fe) and zinc (Zn) content of 12 native-floury cultivars (fresh / boiled tuber samples) and 9 native-bitter cultivars (boiled unprocessed / boiled processed tuber samples) was conduced. Additionally, the nutritional composition of the native-floury cultivars was determined after 3 and 5 months of storage under farmer conditions. A food intake study was conducted during two contrasting periods of food availability (abundance versus scarcity) in order to quantify and characterize the contribution of the potato, different cultivar categories and other food sources to the diet of children between 6 and 36 months of age and their mothers. The specific method consisted of direct measurement of food intake by weight during a 24 hour period for each household (77 households). Further, the overall nutritional status of 340 children aged between 4 and 16 years was determined. Selected cultural connotations of the highland diet were investigated through participant and ethnographic observation, surveys, and workshops. Results show that several native-floury cultivars contain higher contents of specific nutrients (protein, iron) than those commonly reported as representative for native potato cultivars. This suggests that infraspecific diversity can make a valuable contribution to enhanced nutrition. Storage does not affect the nutritional quality of native-floury cultivars very significantly while traditional freeze-drying of native-bitter cultivars considerably reduces protein and zinc content. The research shows that malnutrition in Huancavelica is primarily a consequence of micronutrient deficiency and secondarily of insufficient total energy coverage. The highland diet is heavily dependent on staple foods, particularly potato and barley, and generally short in vegetable, fruit, meat and milk intake. The potato contributes significantly to the nutritional balance and the recommended requirements for energy, protein, iron and zinc of women and children during periods of both food abundance and scarcity. Improved and native-floury cultivars complement each other as each category provides the bulk of potatoes consumed at different moments in time. The consumption of diverse potato cultivars is entangled with cultural constructions of meals and local perceptions of preference traits and quality. The potato itself, as a food item, is no socioeconomic class marker. However, certain dishes or products and the overall cultivar diversity grown and used by a household shape perceptions of relative wealth. Conclusions and implications Chapter 8 highlights the main conclusions of the study and provides answers to the original research questions while taking the different system levels explored throughout the thesis into account. Selected priority areas of future research are identified and, where appropriate, links to other parts of the Andes are drawn. Furthermore, the implications for externally driven R&D oriented in-situ conservation efforts seeking to support dynamic and ongoing farmer-driven conservation are discussed. It is argued that the science and practice of R&D oriented in-situ conservation lag behind the policy commitments to its implementation and that institutional learning from diverse projects already implemented throughout the Andes and the diffusion of key lessons is essential for the success of future interventions
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Network Q
No full textA press release from Network Q announcing that they will begin featuring Brian McNaught, a gay columnist and author, for a monthly segment
Network Q
No full textA press release from Network Q announcing that they will begin featuring Brian McNaught, a gay columnist and author, for a monthly segment
The importance of network goals for strategic chain management
No full textNowadays food products are increasingly produced in supply chain networks that involve numerous firms. Due to their pyramidal-hierarchical structure, such networks possess a focal company that coordinates the network. The managerial task of the focal company is to work out collective strategy that addresses cooperation and coordination problems at the firm, dyadic and network levels. These strategies must take into account that at each level specific goals must be achieved. Though the focal company is a strategy setting unit that sets network goals, other network actors may perceive these goals as firm-level goals of the focal company. Therefore, conflicts may occur in supply chain networks.Supply chain networks, focal company, network goals, Agribusiness,
Innovate and prosper: ensuring Australia's future competitiveness through university-industry collaboration
No full textExecutive summary
The continuation of Australia’s economic growth is under threat. In order to sustain the levels of prosperity we have previously experienced, we have to build on our competitive edge in key industries to remain globally competitive. Alongside these developments, Australia’s higher education system is under increased pressure to become more productive and develop courses that address employability. Innovation represents the most reliable and sustainable solution to transition into a high value, high wage economy. Yet Australia ranks 29th out of 30 in the Organisation for Economic Co-operation and Development (OECD) in terms of the proportion of large businesses and small to medium enterprises (SMEs) collaborating with higher education and public research institutions on innovation.
This report acts as the next level of detail to publications such as the Department of Industry’s Boosting the Commercial Returns from Research report and the Business Council of Australia’s Building Australia’s Comparative Advantages, which have highlighted Australia’s poor performance in collaborative innovation.
We present five recommendations that are a call to action to universities, industry and Government to take the necessary steps to build an innovation economy. They are not a call for additional funding from Government, rather a more effective way of using our existing resources. PricewaterhouseCoopers (PwC) have engaged with leading figures from industry, including the Australian Industry Group (Ai Group), and partnered with the ATN to develop this five point action plan for Government, the university sector and industry 5 that will provide incentives and impetus for collaboration.
Our recommendations include:
Rebalance the national research agenda to underpin Australia\u27s economy and future prosperity
Create incentives for university-industry collaboration
Train researchers for diverse careers
Enhance career mobility between industry, academia and government
Provide incentives for co-investment in research infrastructure between universities, industry and state and federal government
Each recommendation contains a number of practical strategies for consideration by Government, universities and industry. The hope is that the report will encourage dialogue between the three groups and prompt bold policy changes in the coming 12 months and beyond.
 
Contrôle géodynamique des transferts de masses entre une chaîne et son piémont : exemples du mégacône du Napo-Pastaza (Equateur-Pérou)
No full textLes relations entre un bassin versant et son piedmont sont complexes. Elles mettent notamment en œuvre ont appel à des phénomènes physiques incluant l'érosion, le transport et la répartition 3D des zones d'accumulations de sédiments.
L'étude du méga-cône de piedmont du Napo-Pastaza sur le piedmont des Andes d'Equateur et du Pérou et de ses relations avec son bassin d'alimentation permet de mettre en évidence divers types de contrôles, liés à la géodynamique, influant sur la morphologie fluviale, la structure du réseau hydrographique et les transferts de masse entre la chaine des Andes et son piedmont amazonien.
A partir de données hydro-pluviométriques et hydro-sédimentologiques recueillies sur une période de 5 ans sur le Rio Napo et contenant un épisode éruptif d'un volcan se situant dans le bassin versant, nous pouvons mettre en évidence le rôle de l'érosion et du transport des produits de l'éruption (cendres) sur le transport de matières en suspension et l'évolution de la morphologie du cours d'eau.
L'exploitation de données cartographiques, photogrammétriques et d'imagerie satellitaire couvrant le dernier siècle (de 1906 à 2008) concernant un tronçon du Rio Pastaza, localisé dans une zone sismiquement active de la zone subandine permet de mettre en évidence un changement de morphologie associé une série d'avulsions partielle directement liées à la déformation de surface.
L'étude sur les derniers 20 000ans de l'évolution du drainage distributif du cône du Rio Pastaza montre un grand nombre de traces d'avulsions successives. Ces avulsions peuvent être reliées, suivant leur localisation et leur enchainement, soit à un contrôle tectonique direct quand ces avulsions sont situées aux voisinages du front actif de la chaîne, soit à un contrôle indirect, lié a des phénomènes d'augmentation brusque de la charge sédimentaire lorsque ces avulsions ce sont produites dans le partie distale du cône de piedmont. Dans ce cas ces surcroît de sédiments peuvent-être, entre autres, lié aux éruptions volcaniques dans le bassin versant.The relationships between a catchment and sedimentation on its foothill are complex. They involve physical phenomena such as erosion, particles transport and location of sedimentation area.
The study of the Napo-Pastaza megafan, on the Amazonian foothills of Ecuador end Northern Peru and in relation with its catchment led us to evidence different kind of controlling factors related to the local geodynamic context. These factors control fluvial morphology, drainage network structure as well as suspended load transport from the Andes to the amazonian foothill.
A study led on Hydropluviometric and hydrosedimentologic data concerning the Rio Napo, covering 5 years and a volcanc eruption of the Reventador volcano, located in the Rio Napo catchment, we can evidence the role of the erosion and the transport of the products of eruption such as cinders on the transport of the suspended load and the morphology of the river.
The compilation of historic topographic data, aerial photography and satelite images over the last century (from 1906 to 2008) of a reach of the Rio Pastaza located in a sismically active area of the andean foothill show a progressive change of the morphology of the Rio Pastaza associated with several partial avulsions. These avulsions are directly controlled by local superficial deformation.
The mapping of the successive reaches of the Rio Pastaza since the Last Glacial Maximum revealed a great amount of avulsions traces. Depending on the location of the avulsions nodes, these avulsions can be related to several controlling factors. The nodes located close to the active tectonic front of the Andes can be the result of local tectonics. The nodes located in the distal part of the megafan results from sharp increase of the sedimentary load in the channel and its sedimentation in the lower reach of the river. Such an increase of the sedimentary can result, among others, from volcanic eruptions in the catchment
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