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51.
ABSTRACT

Rapidly growing populations, urbanisation and income are together triggering increased demand for high-value agricultural commodities across Southern Africa with scope for gains from trade and regional integration. The poultry sector in Zambia, in particular, has witnessed a rapid growth triggering increased investments and competition, benefiting the consumers. Despite this growth, the sector still faces huge challenges hindering the development of the animal feed, feed input and poultry production sub-sectors. This has limited the extent of participation of the Zambian poultry industry in the regional market due to uncompetitive prices. This study analyses the animal feed to poultry value chain in Zambia, focusing on the industry capabilities with a view to enhancing its competitiveness and production for the regional market. Enhancing value chain capabilities will require improvements in productivity and production of key poultry inputs, and addressing transportation inefficiencies and coordination among governments.  相似文献   
52.
European farmland hosts a species assemblage of animals and plants which have undergone declines through the late twentieth and early twenty-first centuries, at least partly as a result of increased productivity. Further increases in human populations, changes in availability and cost of raw materials, policy constraints, price volatility and climatic changes will further drive greater efficiency and high yields in agriculture, with the risk of further adverse environmental impacts. We assess the effects of different management priorities (production-driven cropping vs. wildlife-friendly farming) at an arable farm in eastern England on food production, greenhouse gas (GHG) emissions and biodiversity. We modelled one actual and three alternative cropping scenarios using actual yields from the farm over 13 years, to calculate total yields and those foregone for agri-environmental measures. We measured crop yields, relative abundance of 19 farmland bird species, and CO2 and N2O emissions related to crop production. Removing up to 10.5% of land from production coupled with a more diverse rotation (including legumes) resulted in a large increase in breeding birds (177%) and reduction of 9.4% in GHG emissions at the cost of 9.6% of food energy. Food protein lost was only 2.9%. A smaller increase in bird numbers of 50% could be achieved at a much smaller cost to yield (~1.7% energy or protein) but with correspondingly smaller emissions reductions (1.2%). Results are discussed within the context of continued biodiversity loss to agriculture, increasing food demand and changing diets.  相似文献   
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Suppliers are increasingly being involved in interorganizational new product development (NPD) teams. Successful management of this involvement is critical both to the performance of the new product and to meeting the project's goals. Yet the transfer of knowledge between buyer and supplier may be subject to varying degrees of causal ambiguity, potentially limiting the effect of supplier involvement on performance. Understanding the dynamics of causal ambiguity within interorganizational product development is thus an important unanswered empirical question. A theoretical model is developed exploring the effect of supplier involvement practices (supplier involvement orientation, relationship commitment, and involvement depth) on the level of causal ambiguity experienced within interorganizational NPD teams, and the subsequent impact on time to competitor imitation, new product advantage, and project performance. The model also serves as a test of the paradox that causal ambiguity both inhibits imitation by competitors, but adversely affects organizational outcomes. Survey data collected from 119 research and development‐intensive manufacturing firms in the United Kingdom largely support these hypotheses. Results from structural equation modeling show that supplier involvement orientation and long‐term relationship commitment lower causal ambiguity within interorganizational NPD teams. The results also shed light on the causal ambiguity paradox showing that causal ambiguity during interorganizational NPD decreases both product and project performance, but has no significant effect on time to competitor imitation. Instead, competitor imitation is delayed by the extent to which the firm develops a new product advantage within the market. A product development strategy based upon maintaining interfirm causal ambiguity to delay competitor imitation is thus unlikely to result in a sustainable competitive advantage. Instead, managers are encouraged to undertake supplier involvement practices aimed at minimizing the level of knowledge ambiguity in the NPD project, and in doing so, improve product and project‐related performance.  相似文献   
54.
This paper is in general concerned with the role of firm heterogeneity for economic growth. We focus on heterogeneous productivity in innovation and credit constraints of firms within a semi-endogenous growth model reflecting recent empirical findings on firm heterogeneity. Our model allows for an explicit solution for transitional growth and for the balanced growth path level of innovations or ideas. The model predicts an optimal degree of heterogeneity in the presence of an endogenous firm distribution. This enables us to draw inference about the impact of key policy parameters of the model on these quantities and to draw conclusions about firm and capital market related policies.  相似文献   
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Introduction     
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58.
This study assesses changes over the past decade in the farm size distributions of Ghana, Kenya, Tanzania, and Zambia, drawing on two or more waves of nationally representative population‐based and/or area‐based surveys. Analysis indicates that much of Sub‐Saharan Africa is experiencing major changes in farm land ownership patterns. Among all farms below 100 hectares in size, the share of land on small‐scale holdings under five hectares has declined except in Kenya. Medium‐scale farms (defined here as farm holdings between 5 and 100 hectares) account for a rising share of total farmland, especially in the 10–100 hectare range where the number of these farms is growing especially rapidly. Medium‐scale farms control roughly 20% of total farmland in Kenya, 32% in Ghana, 39% in Tanzania, and over 50% in Zambia. The numbers of such farms are also growing very rapidly, except in Kenya. We also conducted detailed life history surveys of medium‐scale farmers in each of these four countries and found that the rapid rise of medium‐scale holdings in most cases reflects increased interest in land by urban‐based professionals or influential rural people. About half of these farmers obtained their land later in life, financed by nonfarm income. The rise of medium‐scale farms is affecting the region in diverse ways that are difficult to generalize. Many such farms are a source of dynamism, technical change, and commercialization of African agriculture. However, medium‐scale land acquisitions may exacerbate land scarcity in rural areas and constrain the rate of growth in the number of small‐scale farm holdings. Medium‐scale farmers tend to dominate farm lobby groups and influence agricultural policies and public expenditures to agriculture in their favor. Nationally representative Demographic and Health Survey (DHS) data from six countries (Ghana, Kenya, Malawi, Rwanda, Tanzania, and Zambia) show that urban households own 5–35% of total agricultural land and that this share is rising in all countries where DHS surveys were repeated. This suggests a new and hitherto unrecognized channel by which medium‐scale farmers may be altering the strength and location of agricultural growth and employment multipliers between rural and urban areas. Given current trends, medium‐scale farms are likely to soon become the dominant scale of farming in many African countries.  相似文献   
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This study investigates the impact of two organizational antecedents, (1) Six Sigma resources (technical) and (2) team psychological safety (social), on learning behaviour and knowledge creation and, in turn, on the success of Six Sigma process improvement projects. The paper proposes an integrated model to explain process improvement implementation success through two learning activities undertaken by Six Sigma project teams: Knowing-what and Knowing-how. The conceptualization of these knowledge types in this research is different from usual conceptualization as it represents the knowledge brought into projects through various phases of Six Sigma projects. The three hypotheses proposed in the model were tested using the data collected from 52 Six Sigma project teams from a single organization. Regression analysis showed psychological safety affects project performance through knowing-how. Regression and bootstrapping analyses showed resources influence project performance through the combined mediation of knowing-what and knowing-how.The paper provides an interdisciplinary treatment of knowledge management in process improvement teams, and offers a research model demonstrating how Six Sigma project teams promote deliberate organizational learning. By doing so, this study empirically establishes the notion that technical and social supports jointly impact the success of operations management initiatives such as Six Sigma through learning. The limitations of the study along with the future research directions are highlighted.  相似文献   
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