No. 05: Mapping the Informal Food Economy in Cape Town, South Africa

The informal food retail sector is an important component of urban food systems and plays a vital role in ensuring access to food by the urban poor. Yet, policy frameworks both to address food security and to govern the informal sector neglect informal retail in the food system and, as a result, the sector is poorly understood. This discussion paper argues that it is essential to understand the dynamics of the informal food retail sector, which is diverse in terms of products traded as well as the business models utilized. The paper attempts to identify the characteristics of the sector that impact on its ability to address the food needs of the neighbourhoods in which the businesses are located. It illustrates that far from existing independently of each other, the informal and the formal food retail sectors intersect at various points upstream as well as through customer practices. The paper argues that it is essential to view the formal and informal sectors as part of the same food system and to generate policy and planning responses that acknowledge the role of both in meeting local food security needs. Although the paper is focused on Cape Town, South Africa, the findings are of broader relevance

No. 11: The State of Food Insecurity in Cape Town

Cape Town is one of the wealthiest cities in the Southern African region. Yet, the vast majority of households in poor areas of the city experience food insecurity. This paper uses AFSUN data to examine the characteristics and drivers of food insecurity in Cape Town. While food insecurity correlates closely with income poverty and household structure, broader factors also impact upon urban food security, most notably urban design and market structure. Efforts to address urban food insecurity should therefore not simply target the household. Instead, a food systems approach is necessary, which considers supply chains, procurement, nutrition support programmes, public health, environmental sustainability, water and waste, the support of local enterprise and so on. Furthermore, this approach must consider the geography of the urban food system, in particular planning and zoning regulations regarding the location of both formal and informal food retail within low-income areas of the city

The Lifetimes of Phases in High-Mass Star-Forming Regions

High-mass stars form within star clusters from dense, molecular regions, but is the process of cluster formation slow and hydrostatic or quick and dynamic? We link the physical properties of high-mass star-forming regions with their evolutionary stage in a systematic way, using Herschel and Spitzer data. In order to produce a robust estimate of the relative lifetimes of these regions, we compare the fraction of dense, molecular regions above a column density associated with high-mass star formation, N(H2) > 0.4-2.5 x 10^22 cm^-2, in the 'starless (no signature of stars > 10 Msun forming) and star-forming phases in a 2x2 degree region of the Galactic Plane centered at l=30deg. Of regions capable of forming high-mass stars on ~1 pc scales, the starless (or embedded beyond detection) phase occupies about 60-70% of the dense, molecular region lifetime and the star-forming phase occupies about 30-40%. These relative lifetimes are robust over a wide range of thresholds. We outline a method by which relative lifetimes can be anchored to absolute lifetimes from large-scale surveys of methanol masers and UCHII regions. A simplistic application of this method estimates the absolute lifetimes of the starless phase to be 0.2-1.7 Myr (about 0.6-4.1 fiducial cloud free-fall times) and the star-forming phase to be 0.1-0.7 Myr (about 0.4-2.4 free-fall times), but these are highly uncertain. This work uniquely investigates the star-forming nature of high-column density gas pixel-by-pixel and our results demonstrate that the majority of high-column density gas is in a starless or embedded phase.Comment: 10 pages, accepted to Ap

No. 24: Mapping the Invisible: The Informal Food Economy of Cape Town, South Africa

The informal food retail sector, which is diverse in terms of products traded as well as business models utilized, is an important component of urban food systems and plays a vital role in ensuring access to food by the urban poor. Yet, policy frameworks both to address food security and to govern the informal sector neglect informal retail in the food system and, as a result, the sector is poorly understood. This report attempts to identify the characteristics of the sector that impact on its ability to address the food needs of the neighbourhoods in which the businesses are located. The findings illustrate that far from existing independently of each other, the informal and the formal food retail sectors intersect at various points upstream as well as through customer practices. It is therefore essential to view the formal and informal food sectors as part of the same food system and to generate policy and planning responses that acknowledge the role of both in meeting local food security needs. If South Africa’s constitutional right to food is to be achieved, it will be necessary to develop a multi-departmental food system and food security strategy that champions and facilitates the progressive realization of the right of all residents to access sufficient, nutritious, safe and culturally appropriate food. Although the research in this report is focused on Cape Town, South Africa, the findings are of broader relevance

There are no starless massive proto-clusters in the first quadrant of the Galaxy

We search the lambda = 1.1 mm Bolocam Galactic Plane Survey for clumps containing sufficient mass to form ~10^4 M\odot star clusters. 18 candidate massive proto-clusters are identified in the first Galactic quadrant outside of the central kiloparsec. This sample is complete to clumps with mass M(clump) > 10^4 M_sun and radius r < 2.5 pc. The overall Galactic massive cluster formation rate is CFR(M_cluster > 10^4) ~ 5 Myr^-1, which is in agreement with the rates inferred from Galactic open clusters and M31 massive clusters. We find that all massive proto-clusters in the first quadrant are actively forming massive stars and place an upper limit of t_starless < 0.5 Myr on the lifetime of the starless phase of massive cluster formation. If massive clusters go through a starless phase with all of their mass in a single clump, the lifetime of this phase is very short.Comment: Accepted to ApJL. See also Bressert et al 2012, http://arxiv.org/abs/1208.347

An interface to virtual environments for people who are blind using Wii technology - mental models and navigation

Accessible games, both for serious and for entertainment purposes, would allow inclusion and participation for those with disabilities. Research into the development of accessible games, and accessible virtual environments, is discussed. Research into accessible Virtual Environments has demonstrated great potential for allowing people who are blind to explore new spaces, reducing their reliance on guides, and aiding development of more efficient spatial maps and strategies. Importantly, Lahav and Mioduser (2005, 2008) have demonstrated that, when exploring virtual spaces, people who are blind use more and different strategies than when exploring real physical spaces, and develop relatively accurate spatial representations of them. The present paper describes the design, development and evaluation of a system in which a virtual environment may be explored by people who are blind using Nintendo Wii devices, with auditory and haptic feedback. The nature of the various types of feedback is considered, with the aim of creating an intuitive and usable system. Using Wii technology has many advantages, not least of which are that it is mainstream, readily available and cheap. The potential of the system for exploration and navigation is demonstrated. Results strongly support the possibilities of the system for facilitating and supporting the construction of cognitive maps and spatial strategies. Intelligent support is discussed. Systems such as the present one will facilitate the development of accessible games, and thus enable Universal Design and accessible interactive technology to become more accepted and widespread