No. 12: The State of Food Insecurity in Johannesburg

Johannesburg is the economic hub of South Africa and the Southern African region. At the same time, it is a city of extremes which juxtaposes ostentatious wealth and conspicuous consumption with grinding poverty and food insecurity. Not enough is known about the prevalence and nature of food insecurity in the city, making it dif!cult to challenge and plan to reduce the urban food gap. This paper uses AFSUN data from three lower-income areas of the city (Alexandra, Orange Farm and the Inner City) to examine the characteristics and drivers of food insecurity in Johannesburg. Despite high overall levels of food insecurity, the three study areas exhibited important differences. While the proportion of food secure households was similar in each area, the proportion of severely food insecure households was highest in the informal settlement of Orange Farm and lowest in Alexandra. Household food insecurity is directly linked to household income as the vast majority of food consumed is purchased not grown. In general, the poorer the household, the greater the proportion of household income that is spent on food. Households rely signi!cantly on supermarkets and the informal food economy as food sources. Less than ten percent are involved in any form of urban agriculture or receive food transfers directly from rural areas. This paper also shows that food insecurity correlates with poor health outcomes and concludes with a discussion of the policy implications of the AFSUN study

The influence of CEO political outspokenness on stock market reaction and firm performance

CEOs\u27 public communications are considered essential parts of their stakeholder management efforts. Specifically, CEOs\u27 oral and written communications pertaining to their firms\u27 actions receive scrutiny from external stakeholders (e.g. investors, stock analysts, regulators) and members of the media (Conaway & Wardrope, 2010; Kassel, 2017). There is a burgeoning body of research on CEO communication. Research evidence, for instance, points to the extent to which CEOs\u27 communications influence firm performance and investor behavior (Whittington, Yakis-Douglas, Ahn, 2016; Elliott, Grant & Hodge, 2018). Furthermore, CEOs\u27 communications have been shown to shape firm reputation and stakeholder perceptions in times of crises (Seeger, Sellnow & Ulmer, 2003). In recent years, there have been reports of a growing number of CEOs publicly weighing in on controversial public policy debates (Chatterji & Toffel, 2016; Soergel, 2016). These CEOs are addressing a wide range of societal hot button issues in the political arena. This trend is considered unusual because it goes against the implicit societal expectation that CEOs refrain from being involved in controversial political debates and instead focus on managing their businesses. We refer to this growing trend as CEO political outspokenness and define it as CEO\u27s public and opinionated expression of personal beliefs and values on controversial political issues. Because this trend is very nascent, scholarly research has not examined the consequences of controversial political comments made by CEOs on firm performance. In exploring this issue, we consider two important contingency factors that moderate the impact of CEO political outspokenness on firm performance: firm \u27s past reputation ( Celebrity Status) and history of consumer activism. In the next section, we first provide an overview of CEO political outspokenness. We will then present our study\u27s predictions and conclude by highlighting the scholarly and managerial implications of our empirical findings

No. 12: The State of Food Insecurity in Johannesburg

Johannesburg is the economic hub of South Africa and the Southern African region. At the same time, it is a city of extremes which juxtaposes ostentatious wealth and conspicuous consumption with grinding poverty and food insecurity. Not enough is known about the prevalence and nature of food insecurity in the city, making it dif!cult to challenge and plan to reduce the urban food gap. This paper uses AFSUN data from three lower-income areas of the city (Alexandra, Orange Farm and the Inner City) to examine the characteristics and drivers of food insecurity in Johannesburg. Despite high overall levels of food insecurity, the three study areas exhibited important differences. While the proportion of food secure households was similar in each area, the proportion of severely food insecure households was highest in the informal settlement of Orange Farm and lowest in Alexandra. Household food insecurity is directly linked to household income as the vast majority of food consumed is purchased not grown. In general, the poorer the household, the greater the proportion of household income that is spent on food. Households rely signi!cantly on supermarkets and the informal food economy as food sources. Less than ten percent are involved in any form of urban agriculture or receive food transfers directly from rural areas. This paper also shows that food insecurity correlates with poor health outcomes and concludes with a discussion of the policy implications of the AFSUN study

Nucleon Structure and High Energy Scattering

If the pomeron is generated by a two gluon exchange there is no a priori reason for a drastic suppression of three gluon exchange with negative parity and charge parity. This would lead to an unacceptably large difference between $p\,p$ and $p\, \bar{p}$ scattering. It is shown that a natural suppression of the $C$=$P$=--1 contribution to high energy scattering is given by a cluster structure of the nucleon.Comment: 10 pages, epsf.sty and a4wide.sty, 8 eps figs included complete PS-file (with all figs) available at: http://www.thphys.uni-heidelberg.de/~rueter

Using polymer electrolyte membrane fuel cells in a hybrid surface ship propulsion plant to increase fuel efficiency

Thesis (Nav. E.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and, (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2010.Cataloged from PDF version of thesis.Includes bibliographical references (p. 59).An increasingly mobile US Navy surface fleet and oil price uncertainty contrast with the Navy's desire to lower the amount of money spent purchasing fuel. Operational restrictions limiting fuel use are temporary and cannot be dependably relied upon. Long term technical research toward improving fuel efficiency is ongoing and includes advanced gas turbines and integrated electric propulsion plants, but these will not be implemented fleet wide in the near future. The focus of this research is to determine if a hybrid fuel cell and gas turbine propulsion plant outweigh the potential ship design disadvantages of physically implementing the system. Based on the potential fuel savings available, the impact on surface ship architecture will be determined by modeling the hybrid fuel cell powered ship and conducting a side by side comparison to one traditionally powered. Another concern that this solution addresses is the trend in the commercial shipping industry of designing more cleanly running propulsion plants.Douglas M. Kroll.S.M.in Engineering and ManagementNav.E

Role of Factor Xa Inhibitors in Cancer-Associated Thrombosis: Any New Data?

The association between cancer and venous thromboembolism (VTE) has been well documented in the literature. Prevention and treatment of VTE in cancer patients is imperative. Typically, the mainstay regimen for VTE prevention and treatment has been anticoagulation therapy, unless contraindicated. This therapy consists of unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), factor Xa inhibitor, or vitamin K antagonist (VKA). Current guidelines recommend LMWH over VKA for the treatment of VTE in cancer patients. Factor-specific anticoagulants have been proven safe and effective, and recently factor Xa inhibitors have emerged as a treatment alternative to heparins and VKA. Currently, three factor Xa inhibitors have been identified: fondaparinux (the only one approved so far by the US Food and Drug Administration), idraparinux (in clinical trials), and idrabiotaparinux (in clinical trials). This paper will examine the role of these agents, focusing on fondaparinux, for the prevention and treatment of VTE in cancer patients

Infinite Momentum Frame Calculation of Semileptonic Heavy \Lambda_b\to\Lambda_c Transitions Including HQET Improvements

We calculate the transition form factors that occur in heavy $\Lambda$-type baryon semileptonic decays as e.g. in $\Lambda_{b} \to \Lambda_{c}^{+} + l^{-} + \bar{\nu}_{l}$. We use Bauer-Stech-Wirbel type infinite momentum frame wave functions for the heavy $\Lambda$-type baryons which we assume to consist of a heavy quark and a light spin-isospin zero diquark system. The form factors at $q^{2} = 0$ are calculated from the overlap integrals of the initial and final $\Lambda$-type baryon states. To leading order in the heavy mass scale the structure of the form factors agrees with the HQET predictions including the normalization at zero recoil. The leading order $\omega$-dependence of the form factors is extracted by scaling arguments. By comparing the model form factors with the HQET predictions at ${\cal O}(1/m_{Q})$ we obtain a consistent set of model form factors up to ${\cal O}(1/m_{Q})$. With our preferred choice of parameter values we find that the contribution of the non-leading form factor is practically negligible. We use our form factor predictions to compute rates, spectra and various asymmetry parameters for the semi-leptonic decay $\Lambda_{b} \to \Lambda_{c}^{+} + l^{-} + \bar{\nu}_{l}$.Comment: 24 pages, LaTeX, 6 figures are included in PostScript format. Final version of paper to appear in Phys.Rev.

Interplay of Fluorescence and Phosphorescence in Organic Biluminescent Emitters

Biluminescent organic emitters show simultaneous fluorescence and phosphorescence at room temperature. So far, the optimization of the room temperature phosphorescence (RTP) in these materials has drawn the attention of research. However, the continuous wave operation of these emitters will consequently turn them into systems with vastly imbalanced singlet and triplet populations, which is due to the respective excited state lifetimes. This study reports on the exciton dynamics of the biluminophore NPB (N,N-di(1-naphthyl)-N,N-diphenyl-(1,1-biphenyl)-4,4-diamine). In the extreme case, the singlet and triplet exciton lifetimes stretch from 3 ns to 300 ms, respectively. Through sample engineering and oxygen quenching experiments, the triplet exciton density can be controlled over several orders of magnitude allowing to studying exciton interactions between singlet and triplet manifolds. The results show, that singlet-triplet annihilation reduces the overall biluminescence efficiency already at moderate excitation levels. Additionally, the presented system represents an illustrative role model to study excitonic effects in organic materials.Comment: 45 pages, 10 figures (main manuscript and supplementary information

No. 02: The State of Urban Food Insecurity in Southern Africa

The number of people living in urban areas is rising rapidly in Southern Africa. By mid-century, the region is expected to be 60% urban. Rapid urbanization is leading to growing food insecurity in the region’s towns and cities. This paper presents the results of the first ever regional study of the prevalence of food insecurity in Southern Africa. The AFSUN food security household survey was conducted simultaneously in 2008-9 in 11 cities in 8 SADC countries. The results confirm high levels of food insecurity amongst the urban poor in terms of food availability, accessibility, reliability and dietary diversity. The survey provides important insights into the causes of food insecurity and the kinds of households that are most vulnerable to food insecurity. It also shows the heavy reliance of the urban poor on informal food sources and the growing importance of supermarket chains