Accelerating technical change through ICT: Evidence from a video-mediated extension experiment in Ethiopia

Despite enthusiasm around applications of information and communications technologies (ICTs) to smallholder agriculture in many lower-income countries, there are still many questions on the effectiveness of ICT-based approaches. This study assesses the impacts of video-mediated agricultural extension service provision on farmers’ adoption of improved agricultural technologies and practices in Ethiopia using data from a two-year randomized experiment. Our results show that the video-mediated extension approach significantly increases uptake of recommended technologies and practices by improving extension access and farmer knowledge. Specifically, we find that video-mediated extension reaches a wider audience than the government’s conventional extension approach and leads to higher levels of farmer understanding and uptake of the subject technologies in those locations randomly assigned to the program. While our results also point to greater extension access and greater knowledge among female spouses in locations where both male and female spouses were targeted by the program, we do not find clear evidence that a more inclusive approach translates into higher uptake of the subject technologies. Finally, we find that the video-mediated approach becomes less costly as the scale of operation increases

Examiner Training and Reliability in Two Randomized Clinical Trials of Adult Dental Caries

This report describes the training of dental examiners participating in two dental caries clinical trials and reports the inter- and intra- examiner reliability scores from the initial standardization sessions

Cross-National Analysis of the Associations between Traumatic Events and Suicidal Behavior: Findings from the WHO World Mental Health Surveys

Background Community and clinical data have suggested there is an association between trauma exposure and suicidal behavior (i.e., suicide ideation, plans and attempts). However, few studies have assessed which traumas are uniquely predictive of: the first onset of suicidal behavior, the progression from suicide ideation to plans and attempts, or the persistence of each form of suicidal behavior over time. Moreover, few data are available on such associations in developing countries. The current study addresses each of these issues.Methodology/Principal Findings Data on trauma exposure and subsequent first onset of suicidal behavior were collected via structured interviews conducted in the households of 102,245 (age 18+) respondents from 21 countries participating in the WHO World Mental Health Surveys. Bivariate and multivariate survival models tested the relationship between the type and number of traumatic events and subsequent suicidal behavior. A range of traumatic events are associated with suicidal behavior, with sexual and interpersonal violence consistently showing the strongest effects. There is a dose-response relationship between the number of traumatic events and suicide ideation/attempt; however, there is decay in the strength of the association with more events. Although a range of traumatic events are associated with the onset of suicide ideation, fewer events predict which people with suicide ideation progress to suicide plan and attempt, or the persistence of suicidal behavior over time. Associations generally are consistent across high-, middle-, and low-income countries.Conclusions/Significance This study provides more detailed information than previously available on the relationship between traumatic events and suicidal behavior and indicates that this association is fairly consistent across developed and developing countries. These data reinforce the importance of psychological trauma as a major public health problem, and highlight the significance of screening for the presence and accumulation of traumatic exposures as a risk factor for suicide ideation and attempt.African and African American StudiesPsycholog

Topology Optimization of Transport Problems Modeled by the Boltzmann Equation

Design optimization provides a mechanism to create novel and non-intuitive optimal designs in a formal and mathematical process. The current paradigm for design optimization is to relax the discrete description of a material layout and vary continuously the density of a fictitious porous material. This dissertation builds on a new design optimization paradigm using the level set method (LSM) and the extended finite element method (XFEM). The LSM and the XFEM allow crisp descriptions of the material layout and address numerical artifacts typically seen in density methods. The LSM and XFEM approach is applied to structural problems and fluid-thermal transport problems. Fluid flow is predicted by the Boltzmann equation, which has a simpler numerical formulation than the Navier-Stokes equations and is valid in a larger flow regime. The most popular approach is the lattice Boltzmann method (LBM). This dissertation initially explores the current LBM and density approach to optimization. The theoretical basis to allow LSM and XFEM topology optimization with an alternative to the LBM is presented including a streamline upwind Petrov-Galerkin finite element formulation for the Boltzmann equation and consistent material interpolation in the XFEM. Finally, the finite element hydrodynamic Boltzmann approach is explored for topology optimization of transport problems. The finite element Boltzmann approach is found to address several numerical issues with the LBM at the cost of solving a sparse linear system of equations. The LSM and XFEM approach does not suffer from the numerical artifacts seen in the LBM and density approach. However, a robust regularization strategy has not been developed

Drought-tolerant rice, weather index insurance, and comprehensive risk management for smallholders: evidence from a multi-year field experiment in India

In rainfed production systems throughout India, agricultural activities are dependent upon the summer monsoon, and any aberration in monsoon rainfall patterns can have severe consequences for rice production. There is considerable policy interest in designing programs to lower small-scale farmers’ exposure to these types of risk given the regularity with which adverse monsoon events occur. This paper introduces a field experiment conducted with two risk management options in the state of Odisha: a drought-tolerant rice cultivar; and a weather index insurance product designed to complement the performance of the cultivar. Uptake rates for the cultivar itself and for the joint product are compared across two years alongside an analysis of factors that predict uptake. Results indicate high levels of demand for both the products, albeit with a significant degree of price sensitivity. But this sensitivity is agnostic to the nature of price reductions, suggesting that public investments that lower the costs of risk management may be sufficient to encourage broad uptake, without necessarily relying upon distortionary subsidies as is so often done. Sustained demand between years one and two is primarily explained where individuals were indemnified in year one and had a large number of peers also purchasing the product