842 resultados para diffusion of innovations
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Cassava is one of the major food crops in Nigeria, with multiple uses from human consumption to industrial applications. This study explores the potential of cassava in Nigerian agriculture based on a review of cassava development policies; performs a trend analysis of the cultivation area, production, productivity, and real price of cassava and other competing crops for the period 1961–2013; identifies the sources of growth in production; and examines the production constraints at the local level based on a survey of 315 farmers/processors and 105 marketers from Delta State. The results revealed that several policies and programmes were implemented to develop the cassava sector with mixed outcomes. Although cassava productivity grew at 1.5% per annum (p.a.) during the post-structural adjustment programme period (1993–2013), its real price declined at a rate of 3.5% p.a. The effect of yield is the main source of growth in production, contributing 76.4% of the total growth followed by the area effect (28.2%). The cassava sector is constrained by inadequate market infrastructure, processing facilities, and lack of information and unstable prices at the local level. The widespread diffusion of improved tropical manioc selection technologies and investments in market and marketing infrastructure, processing technologies, irrigation/water provision and information dissemination are recommended to enhance the potential of the cassava sector to support agricultural growth in Nigeria.
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Thesis (Ph.D.)--University of Washington, 2016-06
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Management of customer co-development means involving customers in the development of new products and services, and coordinating the process. In business-tobusiness markets, customer co-development enables the development of innovations that better match customer needs and strengthens customer relationships. However, close collaboration with customers can hamper the innovativeness of new products and lead to overly customized solutions. Therefore, the management of co-development is crucial to its success. Yet the existing research on management of co-development has mainly focused on selecting the right collaboration partners, and the field lacks understanding on how to manage the tensions inherent in customer co-development. The purpose of this thesis is to increase understanding on the management of the codevelopment. The thesis is divided into two parts. The first comprises the literature review and conclusions for the whole study, and the second presents four publications. From the methodological perspective, the research papers follow exploratory qualitative research design. The empirical data comprise interviews with 60 persons, representing 25 different organizations, and a group of 11 end users. The study conceptualizes management of customer co-development in three dimensions 1) relational co-development processes, 2) co-development challenges and paradoxes, and 3) internal customer involvement processes. The findings contribute to the customersupplier relationship, innovation, and marketing management literatures by providing a framework on supplier-customer co-development, addressing co-development paradoxes and their management processes, and suggesting practices for customer involvement. For practitioners, the findings provide tools to manage the challenges related to codevelopment with customers.
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In November 2013 the European Commission issued the “Proposal for a Directive on the European Parliament and of the Council on the protection of undisclosed know-how and business information (trade secrets) against their unlawful acquisition, use and disclosure” (referred to as “TSD”). The TSD offers minimum harmonisation and aims at promoting sharing of knowledge, and the exploitation of innovations on the Internal Market. The European Parliament adopted the TSD on April 14, 2016 and the EU Member States will have two years to implement it. The TSD includes a harmonised definition of a trade secret that builds on the definition provided in Article 39 of the TRIPS Agreement. Moreover, it also ensures the freedom of expression and information and the protection of whistle-blowers. Appropriate means of actions and remedies against unlawful acquisition, use and disclosure of trade secrets are also included, such as provisional and pecuniary measures, injunctions and corrective measures or allocation of damages. This study examines the protection of trade secrets in the course of litigation regulated in Article 9 of the TSD. Currently, the protection of trade secrets within the EU is fragmented especially in this regard, which makes companies reluctant to resort to litigation when a trade secret has unlawfully been misappropriated or it is suspected that a trade secret is being misused. The regulations in Article 9 expand only to the hearing in court. Such protection is welcomed and a step in the right direction. However, in my study I have found that in order for the protection to be sufficient there is a need to further establish measures to protect trade secrets during the entire process, from the filing of the claim to the end when the judgement is given. Consequently, I also discuss different measures that could be used to strengthen the protection of trade secrets before the hearing in court, as evidence are gathered.
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In November 2013 the European Commission issued the “Proposal for a Directive on the European Parliament and of the Council on the protection of undisclosed know-how and business information (trade secrets) against their unlawful acquisition, use and disclosure” (referred to as “TSD”). The TSD offers minimum harmonisation and aims at promoting sharing of knowledge, and the exploitation of innovations on the Internal Market. The European Parliament adopted the TSD on April 14, 2016 and the EU Member States will have two years to implement it. The TSD includes a harmonised definition of a trade secret that builds on the definition provided in Article 39 of the TRIPS Agreement. Moreover, it also ensures the freedom of expression and information and the protection of whistle-blowers. Appropriate means of actions and remedies against unlawful acquisition, use and disclosure of trade secrets are also included, such as provisional and pecuniary measures, injunctions and corrective measures or allocation of damages. This study examines the protection of trade secrets in the course of litigation regulated in Article 9 of the TSD. Currently, the protection of trade secrets within the EU is fragmented especially in this regard, which makes companies reluctant to resort to litigation when a trade secret has unlawfully been misappropriated or it is suspected that a trade secret is being misused. The regulations in Article 9 expand only to the hearing in court. Such protection is welcomed and a step in the right direction. However, in my study I have found that in order for the protection to be sufficient there is a need to further establish measures to protect trade secrets during the entire process, from the filing of the claim to the end when the judgement is given. Consequently, I also discuss different measures that could be used to strengthen the protection of trade secrets before the hearing in court, as evidence are gathered.
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Having into consideration that we live in a multicultural society, it is important to analyse how far people view and accept each other. Therefore, one should reflect upon concepts such as: representations and stereotypes, because they are interpersonal constructs which are (re)built during the interaction of different sociocultural groups. In this study, we focus our attention on the representations a sociocultural group – Portuguese teachers - has of intercultural education and the role of teachers and educators in the promotion of an intercultural approach at school. We believe that teachers have the responsibility to: find out the representations students have of the Other; reconfigure stereotyped representations; and create representations which favor dialogue and relationship with the Other flourish. Following a sociolinguistic approach (Müller, 1998; Vasseur, 2001; Vasseur & Hudelot, 1998), which is related to the construction and diffusion of representations in discourse, we analyse the discourse of teachers during a workshop called ‘The Other and Myself’, in which they build and discuss about a didactic mask that portrays their own vision of both themselves and their ideas of intercultural education.
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Magnesium (Mg) battery is considered as a promising candidate for the next generation battery technology that could potentially replace the current lithium (Li)-ion batteries due to the following factors. Magnesium possesses a higher volumetric capacity than commercialized Li-ion battery anode materials. Additionally, the low cost and high abundance of Mg compared to Li makes Mg batteries even more attractive. Moreover, unlike metallic Li anodes which have a tendency to develop a dendritic structure on the surface upon the cycling of the battery, Mg metal is known to be free from such a hazardous phenomenon. Due to these merits of Mg as an anode, the topic of rechargea¬ble Mg batteries has attracted considerable attention among researchers in the last few decades. However, the aforementioned advantages of Mg batteries have not been fully utilized due to the serious kinetic limitation of Mg2+ diffusion process in many hosting compounds which is believed to be due to a strong electrostatic interaction between divalent Mg2+ ions and hosting matrix. This serious kinetic hindrance is directly related to the lack of cathode materials for Mg battery that provide comparable electrochemical performances to that of Li-based system. Manganese oxide (MnO2) is one of the most well studied electrode materials due to its excellent electrochemical properties, including high Li+ ion capacity and relatively high operating voltage (i.e., ~ 4 V vs. Li/Li+ for LiMn2O4 and ~ 3.2 V vs. Mg/Mg2+). However, unlike the good electrochemical properties of MnO2 realized in Li-based systems, rather poor electrochemical performances have been reported in Mg based systems, particularly with low capacity and poor cycling performances. While the origin of the observed poor performances is believed to be due to the aforementioned strong ionic interaction between the Mg2+ ions and MnO2 lattice resulting in a limited diffusion of Mg2+ ions in MnO2, very little has been explored regarding the charge storage mechanism of MnO2 with divalent Mg2+ ions. This dissertation investigates the charge storage mechanism of MnO2, focusing on the insertion behaviors of divalent Mg2+ ions and exploring the origins of the limited Mg2+ insertion behavior in MnO2. It is found that the limited Mg2+ capacity in MnO2 can be significantly improved by introducing water molecules in the Mg electrolyte system, where the water molecules effectively mitigated the kinetic hindrance of Mg2+ insertion process. The combination of nanostructured MnO2 electrode and water effect provides a synergic effect demonstrating further enhanced Mg2+ insertion capability. Furthermore, it is demonstrated in this study that pre-cycling MnO2 electrodes in water-containing electrolyte activates MnO2 electrode, after which improved Mg2+ capacity is maintained in dry Mg electrolyte. Based on a series of XPS analysis, a conversion mechanism is proposed where magnesiated MnO2 undergoes a conversion reaction to Mg(OH)2 and MnOx and Mn(OH)y species in the presence of water molecules. This conversion process is believed to be the driving force that generates the improved Mg2+ capacity in MnO2 along with the water molecule’s charge screening effect. Finally, it is discussed that upon a consecutive cycling of MnO2 in the water-containing Mg electrolyte, structural water is generated within the MnO2 lattice, which is thought to be the origin of the observed activation phenomenon. The results provided in this dissertation highlight that the divalency of Mg2+ ions result in very different electrochemical behaviors than those of the well-studied monovalent Li+ ions towards MnO2.
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We presented a model that estimates the bioconcentration factor (BCF) of pesticides in potatoes supposing that the pesticide in the soil solution is absorbed by the potato by passive diffusion, following Fick?s second law. The pesticides in the model are nonionic organic substances, traditionally used in potato crops that degrade in the soil according to a first order kinetic equation. This presents an expression that relates BCF with the pesticide elimination rate by the potato, with the pesticide accumulation rate within the potato, with the rate of growth of the potato and with the pesticide degradation rate in the soil. BCF was estimated supposing steady state equilibrium of the quotient between the pesticide concentration in the potato and the pesticide concentration in the soil solution. It is suggested that a negative correlation exists between the pesticide BCF and the soil sorption partition coefficient. The model was built based on the work of Trapp et al. (2007), [Diffusion of PAH in Potato and Carrot Slices and Applications for a Potato Model] in which an expression to calculate the diffusivity of persistent organic substances in potatoes is presented. The model consists in adding to the expression of Trapp et al. (2007) the hypothesis that the pesticide degrades in the soil. The value of BCF suggests which pesticides should be monitored in potatoes.
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Neste artigo, pretende-se desenvolver uma versão desagregada da abordagem pós-Keynesiana para o crescimento econômico, mostrando que de fato esse modelo pode ser tratado como um caso particular do modelo Pasinettiano de mudança estrutural e crescimento econômico. Utilizando-se o conceito de integração vertical, torna-se possível conduzir a análise iniciada por Kaldor (1956) e Robinson (1956, 1962), e seguido por Dutt (1984), Rowthorn (1982) e, posteriormente, Bhaduri e Marglin (1990) em um modelo multi-sectorial em que há aumentos da demanda e produtividade em ritmos diferentes em cada setor. Ao adotar essa abordagem, é possível mostrar que a dinâmica de mudança estrutural está condicionada não apenas aos padrões de demanda de evolução das preferências e da difusão do progresso tecnológico, mas também com as características distributivas da economia, que podem dar origem a diferentes regimes setoriais de crescimento econômico. Além disso, é possível determinar a taxa natural de lucro que faz com que a taxa de mark-up seja constante ao longo do tempo. _________________________________________________________________________________ ABSTRACT
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We describe and evaluate two reduced models for nonlinear chemical reactions in a chaotic laminar flow. Each model involves two separate steps to compute the chemical composition at a given location and time. The “manifold tracking model” first tracks backwards in time a segment of the stable manifold of the requisite point. This then provides a sample of the initial conditions appropriate for the second step, which requires solving one-dimensional problems for the reaction in Lagrangian coordinates. By contrast, the first step of the “branching trajectories model” simulates both the advection and diffusion of fluid particles that terminate at the appropriate point; the chemical reaction equations are then solved along each of the branched trajectories in a second step. Results from each model are compared with full numerical simulations of the reaction processes in a chaotic laminar flow.
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The use of virtual social networks (VSNs) has been prevalent among consumers worldwide. Numerous studies have investigated various aspects of VSNs. However, these studies have mainly focused on students and young adults as they were early adopters of these innovative networks. A search of the literature revealed there has been a paucity of research on adult consumers’ use of VSNs. This research study addressed this gap in the literature by examining the determinants of engagement in VSNs among adult consumers in Singapore. The objectives of this study are to empirically investigate the determinants of engagement in VSNs and to offer theoretical insights into consumers’ preference and usage of VSNs. This study tapped upon several theories developed in the discipline of technology and innovation adoption. These were Roger’s Diffusion of Innovation, Theory of Reasoned Action (TRA), Theory of Planned Behavior (TPB), Technology Acceptance Model (TAM), Conceptual Framework of Individual Innovation Adoption by Frambach and Schillewaert (2002), Enhanced Model of Innovation Adoption by Talukder (2011), Extended Unified Theory of Acceptance and Use of Technology (UTAUT2) and the Information Systems (IS) Success Model. The proposed research model, named the Media Usage Model (MUM), is a framework rooted in innovation diffusion and IS theories. The MUM distilled the essence of these established models and thus provides an updated, lucid explanation of engagement in VSNs. A cross-sectional, online social survey was conducted to collect quantitative data to examine the validity of the proposed research model. Multivariate data analysis was carried out on a data set comprising 806 usable responses by utilizing SPSS, and for structural equation modeling AMOS and SmartPLS. The results indicate that consumer attitude towards VSNs is significantly and positively influenced by: three individual factors – hedonic motivation, incentives and experience; two system characteristics – system quality and information quality; and one social factor – social bonding. Consumer demographics were found to influence people’s attitudes towards VSNs. In addition, consumer experience and attitude towards VSNs significantly and positively influence their usage of VSNs. The empirical data supported the proposed research model, explaining 80% of variance in attitude towards VSNs and 45% of variance in usage of VSNs. Therefore, the MUM achieves a definite contribution to theoretical knowledge of consumer engagement in VSNs by deepening and broadening our appreciation of the intricacies related to use of VSNs in Singapore. This study’s findings have implications for customer service management, services marketing and consumer behavior. These findings also have strategic implications for maximizing efficient utilization and effective management of VSNs by businesses and operators. The contributions of this research are: firstly, shifting the boundaries of technology or innovation adoption theories from research on employees to consumers as well as the boundaries of Internet usage or adoption research from students to adults, which is also known as empirical generalization; secondly, highlighting the issues associated with lack of significance of social factors in adoption research; and thirdly, augmenting information systems research by integrating important antecedents for success in information systems.
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Ion channels are a large class of integral membrane proteins that allow for the diffusion of ions across a cellular membrane and are found in all forms of life. Pentameric ligand-gated ion channels (pLGICs) comprise a large family of proteins that include the nicotinic acetylcholine receptor (nAChR) and the γ-aminobutyric acid (GABA) receptor. These ion channels are responsible for the fast synaptic transmission that occurs in humans and as a result are of fundamental biological importance. pLGICs bind ligands (neurotransmitters), and upon ligand-binding undergo activation. The activation event causes an ion channel to enter a new physical state that is able to conduct ions. Ion channels allow for the flux of ions across the membrane through a pore that is formed upon ion channel activation. For pLGICs to function properly both ligand-binding and ion channel activation must occur. The ligand-binding event has been studied extensively over the past few decades, and a detailed mechanism of binding has emerged. During activation the ion channel must undergo structural rearrangements that allow the protein to enter a conformation in which ions can flow through. Despite this great and ubiquitous importance, a fundamental understanding of the ion channel activation mechanism and kinetics, as well as concomitant structural arrangements, remains elusive.
This dissertation describes efforts that have been made to temporally control the activation of ligand-gated ion channels. Temporal control of ion channel activation provides a means by which to activate ion channels when desired. The majority of this work examines the use of light to activate ion channels. Several photocages were examined in this thesis; photocages are molecules that release a ligand under irradiation, and, for the work described here, the released ligand then activates the ion channel. First, a new water-soluble photoacid was developed for the activation of proton-sensitive ion channels. Activation of acid-sensing ion channels, ASIC2a and GLIC, was observed only upon irradiation. Next, a variety of Ru2+ photocages were also developed for the release of amine ligands. The Ru2+ systems interacted in a deleterious manner with a representative subset of biologically essential ion channels. The rapid mixing of ion channels with agonist was also examined. A detection system was built to monitor ion channels activation in the rapid mixing experiments. I have shown that liposomes, and functionally-reconstituted ELIC, are not destroyed during the mixing process. The work presented here provides the means to deliver agonist to ligand-gated ion channels in a controlled fashion.
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In order to deepen the knowledge about the origin of the CO preoxidation process and the intrinsic catalytic activity of Pt superficial steps toward CO oxidation, a series of CO stripping experiments were performed on stepped Pt electrodes in acidic medium. For the occurrence of CO preoxidation, it was found that it arises (reproducibly) whenever four interconnected conditions are simultaneously fulfilled: (1) CO adsorption at potentials lower than about 0.2 V; (2) on surfaces saturated with COads; (3) in the presence of traces of CO in solution; (4) in the presence of surface steps. If any of these four conditions is not satisfied, the CO preoxidation pathway does not appear, even though the steps on the electrode surface are completely covered by CO. By controlling the removal of the CO adlayer (voltammetrically), we show that once the CO adlayer has been partially oxidized, the (111) terrace sites of stepped surfaces are released earlier than the (110) step sites. Moreover, if (110) steps are selectively decorated with CO, its oxidation occurs only at potentials ∼150 mV higher than the CO preoxidation peak. Our results systematically demonstrate that step sites are less active to oxidize CO than those ones responsible for the CO preoxidation process. Once the sites responsible for the CO preoxidation are made free, there is no apparent motion of the remaining adsorbed CO layer, suggesting that the activation of the surface controls the whole process, rather than the diffusion of COads toward hypothetically “most active sites”. Voltammetric and chronoamperometric experiments performed on partially covered CO adlayers suggest that adsorbed CO behave as a motionless species during its oxidation, in which the CO adlayer is removed piece by piece. By means of in situ FTIR experiments, the stretching frequency of CO selectively adsorbed on (110) step sites was examined. Band frequency results confirm that those molecules adsorbed on steps are fully coupled with the adsorbed CO on (111) terraces when the surface reaches full coverage.
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London, Wellcome Library, MS 411 is a codex in one volume which dates from the late fifteenth century. It houses a collection of practical treatises and tracts in English and Latin, in verse as well as in prose, on different topics including prognostications, nativities, medical astrology, reproduction, toxicology, bloodletting, etc. In this paper, the Middle English anonymous treatise on venomous bites, written in prose and held in folios 56r to 61r, is taken into consideration. The objective is twofold: on the one hand, to examine the contents, transmission and sources of the text and, on the other, to describe it from a physical standpoint. Investigation on those aspects of the treatise contained in Wellcome MS 411 can shed some light on the function and diffusion of the text, and may also prove significant for a better understanding of it.
What Determines the Innovativeness of Polish Family Firms? Empirical Results and Theoretical Puzzles
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This article will review and synthesize the existing research on the innovativeness of Polish family firms in order to separate universal factors that influence the degree of innovativeness of firms from the factors which distinctively influence the innovativeness of family firms. To better assess the innovation propensity of family firms the author will work out the typology by combining the variety of innovations with particular features of family firms and the industrial context. A more nuanced approach will help to understand why the academic literature is inconclusive with regards to the question of whether family firms are anti-innovative (as some authors claim), pro-innovative or ambivalent with regard to innovations. In particular it will be argued that when assessing family firms’ innovativeness special attention needs to be paid to the impact of the management of intergenerational change on the propensity to innovate, as this process relates to the capacity for investments into innovativeness and the time horizon of the owner’s decisions.