186 research outputs found

    Five criteria for choosing among poverty programs

    Get PDF
    The author addresses the issue of how to choose among discreet poverty interventions such as food stamp programs, public works, or small enterprise credit schemes where little formal policy modeling is done prior to decisionmaking. The minimum criteria on which to judge the relative merits of poverty programs are the following. Administrative feasibility. This depends on the detailed designof the program, the level of resources available for administration, and the degree of imperfection that can be tolerated. Political feasibility. This depends on how the program is promoted to the public, how coalitions of supporters or detractors are built, and the relative power of beneficiaries, suppliers, and administrators. Collateral effects on the poverty strategy. How will a safety net program affect, for example, the participants'labor supply, participation in other programs, and receipt of private interhousehold transfers, and how will those changes affect markets and government finances? What will be the net effect on poverty reduction. Potential for targeting the poor. Will the program reach significant number of the poor? How much leakage of benefits will there be to the nonpoor? Tailoring the solution to the problem. The program choice should address the real problem. Where the poor have suffered a loss of real wages rather than a loss of jobs, for example, transfers to the working poor may be more relevant than creating jobs. This criterion may seem obvious, but many proposals seem to ignore it. The author illustrates her main points by applying these criteria to a range of poverty programs commonly used in Latin America. General subsidies of food prices, for example, are administratively and politically feasible and lower food costs to the consumer, but they may distort the economy, harming growth. Food stamps are easy to target to the poor, are fairly difficult to administer, depending on program design, but depending on program design, may encourage the use of schools and primary health care. But there is controversy about whether they encourage dependency and diminish the work ethic.Rural Poverty Reduction,Environmental Economics&Policies,Health Economics&Finance,Services&Transfers to Poor,Safety Nets and Transfers

    An observation on the bias in clinic-based estimates of malnutrition rates

    Get PDF
    Clinic-based data on malnutrition are the most readily available for following malnutrition levels and trends in most countries, but there is a bias inherent in clinic-based estimates of malnutrition rates. The authors compare annual clinic-based malnutrition data and those from four household surveys in Jamaica. The clinic data give lower estimates of malnutrition than the survey data in all four cases - significantly so in three. The size of the bias was variable over time, so the clinic data were not a good indicator of either levels of trends in nutrition status.Health Monitoring&Evaluation,Early Child and Children's Health,Early Childhood Development,Health Systems Development&Reform,Regional Rural Development

    A continuum treatment of growth in biological tissue: The coupling of mass transport and mechanics

    Full text link
    Growth (and resorption) of biological tissue is formulated in the continuum setting. The treatment is macroscopic, rather than cellular or sub-cellular. Certain assumptions that are central to classical continuum mechanics are revisited, the theory is reformulated, and consequences for balance laws and constitutive relations are deduced. The treatment incorporates multiple species. Sources and fluxes of mass, and terms for momentum and energy transfer between species are introduced to enhance the classical balance laws. The transported species include: (\romannumeral 1) a fluid phase, and (\romannumeral 2) the precursors and byproducts of the reactions that create and break down tissue. A notable feature is that the full extent of coupling between mass transport and mechanics emerges from the thermodynamics. Contributions to fluxes from the concentration gradient, chemical potential gradient, stress gradient, body force and inertia have not emerged in a unified fashion from previous formulations of the problem. The present work demonstrates these effects via a physically-consistent treatment. The presence of multiple, interacting species requires that the formulation be consistent with mixture theory. This requirement has far-reaching consequences. A preliminary numerical example is included to demonstrate some aspects of the coupled formulation.Comment: 29 pages, 11 figures, accepted for publication in Journal of the Mechanics and Physics of Solids. See journal for final versio

    AN INVESTIGATION OF CERTAIN THERMODYNAMIC AND TRANSPORT PROPERTIES OF WATER AND WATER VAPOR IN THE CRITICAL REGION

    Full text link
    An accurate knowledge of thermodynamic and transport properties of water in the critical region is required in order to analyze future power cycles, nuclear reactor configurations, and other types of heat transfer apparatus. Preliminnry investigations showed that this was rot possible with presently existing tabulations. Experimentel data from volumetric viscosity and thermal conductivity studies were therefore selected and retabulated. Smoothings of these data are described and, for the first time, a tabulation at close intervals of pressure and temperature of the volumetric data is possible for steam in the critical region. A graphical presentation is given of volumetric data from 700 to 750 deg F. An important result of this study was that excellent agreement existed between the many P-V-T measurements for this substance even though some of the data was obtained many years ago. Differences occurring between the tabulated data of various steam tables were found to arise from the use of inexact equations of state or interpolation techniques rather than from faulty primary data. New P-V-T data were derived from measurements of other investigators, by a graphical technique and it is estimated that it yielded pressure values accurate to some five parts in ten thousand except in the subcooled liquid region (for specific volumes below 0.040 ftsup 3/lb), where the uncertainty may be some twenty parts in ten thousand. Study of the existing thermal conductivity and viscosity data suggests that the Russian work is the most consistent. However, it appears that the empirical equations proposed for interpolation do not adequately represent the data in the critical region. No attempt has been made to derive thermodynamic functions or to analyze the transport data. (auth

    LDRD HPC4Energy Wrapup Report - LDRD 12-ERD-074

    Full text link

    Impact Evaluation of Training Natural Leaders during a Community-Led Total Sanitation Intervention: A Cluster-Randomized Field Trial in Ghana

    Get PDF
    We used a cluster-randomized field trial to evaluate training natural leaders (NLs) as an addition to a community-led total sanitation (CLTS) intervention in Ghana. NLs are motivated community members who influence their peers’ behaviors during CLTS. The outcomes were latrine use and quality, which were assessed from surveys and direct observation. From October 2012, Plan International Ghana (Plan) implemented CLTS in 60 villages in three regions in Ghana. After 5 months, Plan trained eight NLs from a randomly selected half of the villages, then continued implementing CLTS in all villages for 12 more months. The NL training led to increased time spent on CLTS by community members, increased latrine construction, and a 19.9 percentage point reduction in open defecation (p < 0.001). The training had the largest impact in small, remote villages with low exposure to prior water and sanitation projects, and may be most effective in socially cohesive villages. For both interventions, latrines built during CLTS were less likely to be constructed of durable materials than pre-existing latrines, but were equally clean, and more often had handwashing materials. CLTS with NL training contributes to three parts of Goal 6 of the Sustainable Development Goals: eliminating open defecation, expanding capacity-building, and strengthening community participation

    A rheological network model for the continuum anisotropic and viscoelastic behavior of soft tissue

    Full text link
    The mechanical behavior of soft tissue demonstrates a number of complex features including nonlinearity, anisotropy, viscoelasticity, and growth. Characteristic features of the time-dependent and anisotropic behavior are related to the properties of various components of the tissue such as fibrous collagen and elastin networks, large proteins and sugars attached to these networks, and interstitial fluid. Attempts to model the elastic behavior of these tissues based on assumptions about the behavior of the underlying constituents have been reasonably successful, but the essential addition of viscoelasticity to these models has been met with varying success. Here, a new rheological network model is proposed using, as its basis, an orthotropic hyperelastic constitutive model for fibrous tissue and a viscoelastic reptation model for soft materials. The resulting model has been incorporated into numerical and computational models, and is shown to capture the mechanical behavior of soft tissue in various modes of deformation including uniaxial and biaxial tension and simple shear.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47943/1/10237_2004_Article_49.pd
    • …
    corecore