THE RISE OF KENYAN SUPERMARKETS AND THE EVOLUTION OF THEIR FRESH FRUITS AND VEGETABLES PROCUREMENT SYSTEMS

Supermarkets are rapidly penetrating urban food retail in Kenya and spreading well beyond their initial tiny market niche into the food markets of lower-income groups. Having penetrated processed and staple food markets much earlier and faster than fresh foods, they have recently begun to make inroads into the fresh fruits and vegetables category. The important changes in their procurement systems bring significant opportunities and challenges for small farmers, and have implications for agricultural diversification and rural development programmes and policies.Marketing,

SUPERMARKETS AND CONSUMERS IN AFRICA: THE CASE OF NAIROBI, KENYA

Supermarkets are rapidly penetrating urban food retail in Kenya and spreading well beyond their initial tiny market niche into the food markets of lower-income groups. Having penetrated processed and staple food markets much earlier and faster than fresh foods, they have recently begun to make inroads into the fresh fruits and vegetables category. The important changes in their procurement systems bring significant opportunities and challenges for small farmers, and have implications for agricultural diversification and rural development programmes and policies.Consumer/Household Economics, Marketing,

The Feasibility of Dynamically Granted Permissions: Aligning Mobile Privacy with User Preferences

Current smartphone operating systems regulate application permissions by prompting users on an ask-on-first-use basis. Prior research has shown that this method is ineffective because it fails to account for context: the circumstances under which an application first requests access to data may be vastly different than the circumstances under which it subsequently requests access. We performed a longitudinal 131-person field study to analyze the contextuality behind user privacy decisions to regulate access to sensitive resources. We built a classifier to make privacy decisions on the user's behalf by detecting when context has changed and, when necessary, inferring privacy preferences based on the user's past decisions and behavior. Our goal is to automatically grant appropriate resource requests without further user intervention, deny inappropriate requests, and only prompt the user when the system is uncertain of the user's preferences. We show that our approach can accurately predict users' privacy decisions 96.8% of the time, which is a four-fold reduction in error rate compared to current systems.Comment: 17 pages, 4 figure

FARM-LEVEL PERSPECTIVES ON THE IMPACT OF DOMESTIC SUPERMARKETS ON KENYA'S FRESH FRUITS AND VEGETABLES SUPPLY SYSTEM

The rise of supermarkets in Kenya has given rise to a new group of medium-sized farms managed by well-educated farmers. Focusing on kale, the essay shows that nearly all supermarket-channel farmers have the capacity to supply larger volumes year round and have transportation vehicles, an irrigation system, a packing shed, a cellular phone, and so on, pointing to the existence of a threshold capital vector which farmers must have in order to access supermarkets. Especially farm size and irrigation were found to be significant determinants of participation in the supermarket channel. Kale suppliers to supermarkets use more capital intensive production technologies, leading to average labor and land productivities which are 60-70% higher than in the traditional channel. Eighty percent of labor consists of hired workers, indicating that these farmers could be important in alleviating poverty for rural households with little or no land. While most traditional-channel kale farmers sell to brokers and get a price that lets them break-even at best, supermarket-channel farmers have a 40% gross profit margin. These margins and lower market risks in the supermarket channel have resulted in a strong growth dynamic of supermarket-channel farmers which have doubled the size of their operations over the last five years.Marketing,

DETERMINANTS OF FERTILIZER ADOPTION BY AFRICAN FARMERS: POLICY ANALYSIS FRAMEWORK, ILLUSTRATIVE EVIDENCE, AND IMPLICATIONS

Crop Production/Industries,

Incentives for Fertilizer Use in Sub-Saharan Africa: A Review of Empirical Evidence on Fertilizer Response and Profitability

This research addresses two questions: Why is fertilizer not yet fulfilling its potential as a major stimulus to agricultural productivity in SSA? What can be done to improve the situation? Our answers are based on an extensive review of fertilizer response, profitability, and policy literature as well as some analysis of crop budgets and aggregate national statistics on fertilizer consumption. Much of the debate about fertilizer use in SSA focuses on two issues: whether the profit incentive is adequate and, if so, whether farmers have the capacity to access and use it.food security, food policy, fertilizer use, sub-Saharan Africa, Crop Production/Industries, Downloads May 2008-July 2009: 153, Q18,

Tracing the Chromospheric and Coronal Magnetic Field with AIA, IRIS, IBIS, and ROSA Data

The aim of this study is to explore the suitability of chromospheric images for magnetic modeling of active regions. We use high-resolutionimages (≈0.2"-0.3"), from the Interferometric Bidimensional Spectrometer in the Ca II 8542 Å line, the Rapid Oscillations in the Solar Atmosphere instrument in the Hα 6563Å line, the Interface Region Imaging Spectrograph in the 2796Å line, and compare non-potential magnetic field models obtainedfrom those chromospheric images with those obtained from images of the Atmospheric Imaging Assembly in coronal (171 Å, etc.) and inchromospheric (304 Å) wavelengths. Curvi-linear structures are automatically traced in those images with the OCCULT-2 code, to which we forward-fitted magnetic field lines computed with the Vertical-current Approximation Nonlinear Force Free Field code. We find that the chromospheric images: (1) reveal crisp curvi-linear structures (fibrils, loop segments, spicules) that are extremely well-suited for constraining magnetic modeling; (2) that these curvi-linear structures arefield-aligned with the best-fit solution by a median misalignment angle of μ2 ≈ 4°–7° (3) the free energy computed from coronal data may underestimate that obtained from chromospheric data by a factor of ≈2–4, (4) the height range of chromospheric features is confined to h≲4000 km, while coronal features are detected up to h = 35,000 km; and (5) the plasma-β parameter is β ≈ 10^-5 - 10^-1 for all traced features. We conclude that chromospheric images reveal important magnetic structures that are complementary to coronal images and need to be included in comprehensive magnetic field models, something that is currently not accomodated in standard NLFFF codes

The rise of a middle class in East and Southern Africa: Implications for food system transformation

We examine the implications of the rise of a middle class in East and Southern Africa for food consumption patterns and the food system. A unique classification of food items shows that highly processed food has one-third of the purchased food market, with comparable shares in rural and urban areas (31 per cent vs 35 per cent), and among the vulnerable and upper middle classes (33 per cent vs 41 per cent). By linking FAOSTAT import data to consumption bundles, we show that the net import share falls with income in urban areas. Implications for food system change to 2040 are discussed

Food Sector Transformation and Standards in Zambia: Smallholder Farmer Participation and Growth in the Dairy Sector

Market liberalization in Zambia has led to a rapid and fundamental transformation of its dairy sector. Mainly through foreign direct investment and international partnerships, a new formal dairy sector, characterized by institutional, organizational and technological innovation, emerged from the ashes of abandoned government projects. Sensing the development opportunity that arose from an untapped milk supply potential in Zambia's traditional smallholder livestock production and a growing milk demand from the newly emerging formal dairy processing sector, numerous donor-funded smallholder dairy farmer support programs emerged. At the same time, in order to protect its domestic market as well as to be in a better position to enter demanding export markets, stakeholders from the private, public and NGO sector have recently joined forces to develop technical dairy product standards for Zambia based on the CODEX.Livestock Production/Industries,