Improving the Impact of Market Reform on Agricultural Productivity in Africa: How Institutional Design Makes a Difference

Improving the Impact of Market Reform on Agricultural Productivity in Africa: How Institutional Design Makes a Difference Abstract: This paper reviews the emerging empirical record of agricultural marketing policy reform and agricultural productivity, drawing from research on food access and agricultural productivity supported by USAID’s Africa Bureau on seven countries in West, Eastern, and Southern Africa. We also examine key factors constraining past and future performance of the food systems in these countries. The paper concludes by identifying a set of policy issues for further consideration that would help provide the investment incentives to promote productivity growth for the millions of low-input semi-subsistence rural households in the region.food security, food policy, market reform, Agricultural and Food Policy, Marketing, Productivity Analysis, Downloads June 2008 - July 2009: 40, Q13,

STRATEGIC CHOICES IN PRODUCE MARKETING: ISSUES OF COMPATIBLE USE AND EXCLUSION COSTS

Fresh produce suppliers in Europe and the United States use a mix of price and non-price marketing strategies. This paper shows that these strategies create, using Mancur Olson's terms, two collective goods: overall consumer confidence in the market's ability to deliver credence attributes, and overall consumer satisfaction with the experience attributes of fresh produce. The characteristics of these two collective goods, i.e., their compatible use and high costs of exclusion, influence the costs, effectiveness, and nature of the marketing strategies of firms. This paper presents examples from the fresh produce industries of Europe and the U.S. to show how compatible-use and high-exclusion costs influence firm strategies. It concludes that there are unavoidable interdependencies that create a need for collective action -- a need that will increase as consumer and retailer demand for quality attributes in fresh produce increases.Demand and Price Analysis, Marketing,

Optimal Pacing for Running 400 m and 800 m Track Races

Physicists seeking to understand complex biological systems often find it rewarding to create simple "toy models" that reproduce system behavior. Here a toy model is used to understand a puzzling phenomenon from the sport of track and field. Races are almost always won, and records set, in 400 m and 800 m running events by people who run the first half of the race faster than the second half, which is not true of shorter races, nor of longer. There is general agreement that performance in the 400 m and 800 m is limited somehow by the amount of anaerobic metabolism that can be tolerated in the working muscles in the legs. A toy model of anaerobic metabolism is presented, from which an optimal pacing strategy is analytically calculated via the Euler-Lagrange equation. This optimal strategy is then modified to account for the fact that the runner starts the race from rest; this modification is shown to result in the best possible outcome by use of an elementary variational technique that supplements what is found in undergraduate textbooks. The toy model reproduces the pacing strategies of elite 400 m and 800 m runners better than existing models do. The toy model also gives some insight into training strategies that improve performance.Comment: 14 pages, 4 figures, submitted to the American Journal of Physic

The Geospace Dynamics Observatory (GDO) A Paradigm-changing Geospace Mission

No abstract availabl

The Geospace Dynamics Observatory; a Mission of Discovery for Geospace

A few examples of potential advances include: 1. Unparalleled advances in the connection of the upper atmosphere to the Sun. In the aurora and lower latitudes, extending the duration of uninterrupted images would advance understanding of the transfer of energy from the Sun to the upper atmosphere and the response of the space environment. 2. Advances in the influence of waves and tides on the upper atmosphere. Increasing both the signal to noise and the duration ofthe observations would reveal contributions that are not identifiable using other approaches. 3. The ability to probe the mechanisms that control the evolution of planetary atmospheres. The vantage point provided by this mission allows the flux of hydrogen (which is tied to the escape of water from a planet) to be mapped globally. It also allows unique observations of changes in the atmospheric structure and their causes

SAM: A Tool for Measurement of Moderate to Vigorous Physical Activity (MVPA) in School Physical Education

Int J Exerc Sci 5(2) : 127-135, 2012. Observational methods have been a primary methodology used by physical educators for assessing teacher and student behaviors in school physical education (PE) classes for over 30 years. Observational instruments traditionally used in PE are economical, but are time intensive and complicated. Recently national PE recommendations have been promoted to encourage practitioners to achieve ≥ 50% of PE class in moderate to vigorous physical activity (MVPA). The purpose of this preliminary study was to develop, validate, and test the reliability of the Simple Activity Measurement (SAM) instrument for assessing MVPA during school PE classes. Students (N=36, representing grades 3-10) from a convenient sample of schools in San Antonio, TX were randomly selected to wear SUUNTOTM heart rate (HR) monitors during PE classes as an MVPA intensity measure, and the SAM instrument was used to observe 6 classes (N=281 students) for MVPA each minute using the SAM 0-10 scale. The SAM instrument was found to be a significant predictor for HR (r=0.555, r2=0.308, p\u3c0.05) using linear regression, and the intra class correlation coefficient to test reliability was found to be R=0.803, p\u3c0.05. Students averaged 88.5 % of class time spent in MVPA at the elementary level and only 36.5 % of class time spent in MVPA at the high school level. The results of this preliminary study indicate that the SAM has promise to provide school PE evaluators with an effective economical observation tool to document minutes of student MVPA in PE classes, and to promote accountability with national MVPA recommendations