2,723 research outputs found
Mortality reductions from measles and tetanus immunization : a review of the evidence
In recent years, tetanus and measles are estimated to account for more than 2.5 million childhood deaths annually; measles alone may account for more than 2 million such deaths. The author reviews empirical evidence on the most effective and feasible strategies for measles and tetanus vaccination programs. He found that tetanus and measles immunization programs could significantly reduce deaths among children up to the age of 4 in many developing countries. Vaccinations had a pronounced effect in reducing childhood deaths from measles - with benefits sustained over time, and with the greatest benefits accruing to the most disadvantaged children. He found little support for the existence of a replacement mortality effect. Studies on maternal immunization against tetanus showed a great reduction in the number of neonatal deaths, but considerable uncertainty about the number of doses needed and how long the immunity lasted. Recent evidence suggests that giving the mother two doses of tetanus toxoid may confer significant levels of protection against neonatal death from tetanus for 15 years or more. Evidence on the impact of a single dose is less conclusive.Early Childhood Development,Health Indicators,Early Child and Children's Health,Health Monitoring&Evaluation,Adolescent Health
The Formation of Networks with Local Spillovers and Limited Observability
In this paper I analyze the formation of networks in which each agent is assumed to possess some information of value to the other agents in the network. Agents derive payoff from having access to the information of others through communication or spillovers through the links between them. Linking decisions are based on network-dependent marginal payoff and a network independent noise capturing exogenous idiosyncratic effects. Moreover, agents have a limited observation radius when deciding to whom to form a link. I find that for small noise the observation radius does not matter and strongly centralized networks emerge. However, for large noise, a smaller observation radius generates networks with a larger degree variance. These networks can also be shown to have larger aggregate payoff. I then estimate the model using a network of coinventors, firm alliances and trade relationships between countries, and find that the model can closely reproduce the observed patterns. The estimates show that with increasing levels of aggregation, the observation radius is increasing, indicating economies of scale in which larger organizations are able to process greater amounts of information.diļ¬usion, network formation, growing networks, limited observability
Linear State Space Modeling of Gamma-Ray Burst Lightcurves
Linear State Space Modeling determines the hidden autoregressive (AR) process
in a noisy time series; for an AR process the time series' current value is the
sum of current stochastic ``noise'' and a linear combination of previous
values. We present preliminary results from modeling a sample of 4 channel
BATSE LAD lightcurves. We determine the order of the AR process necessary to
model the bursts. The comparison of decay constants for different energy bands
shows that structure decays more rapidly at high energy. The resulting models
can be interpreted physically; for example, they may reveal the response of the
burst emission region to the injection of energy.Comment: 5 pages, 2 figures, AIPPROC LaTeX, to appear in "Gamma-Ray Bursts,
4th Huntsville Symposium," eds. C. Meegan, R. Preece and T. Koshu
Nestedness in Networks: A Theoretical Model and Some Applications
We develop a dynamic network formation model that can explain the observed nestedness in real-world networks. Links are formed on the basis of agentsā centrality and have an exponentially distributed life time. We use stochastic stability to identify the networks to which the network formation process converges and find that they are nested split graphs. We completely determine the topological properties of the stochastically stable networks and show that they match features exhibited by real-world networks. Using four different network datasets, we empirically test our model and show that it fits well the observed networks.Nestedness, Bonacich centrality, network formation, nested split graphs
ScoutPro mobile field scouting applications for corn and soybean
ScoutPro, a startup business from the Agricultural Entrepreneurship Initiative at Iowa State University (ISU), developed corn and soybean scouting apps for use on tablets (such as iPad and Android-based devices) and Smartphones
Patent Royalties Extending Beyond Expiration: An Illogical Ban From Brulotte to Scheiber
A recent decision by the Seventh Circuit Court of Appeals, Scheiber v. Dolby Laboratories, Inc., called into question, yet dutifully applied, the somewhat disfavored Supreme Court patent case of Brulotte v. Thys Co. For thirty-eight years, Brulotte has served as an absolute prohibition on the collection of any patent royalties extending beyond the expiration date of the patent. As Justice Douglas stated in writing for the eight-Justice majority, a patentee\u27s use of a royalty agreement that projects beyond the expiration date of the patent is unlawful per se. Ostensibly, this concise and easily-applied exposition of the law seems sensible enough. But, the devil is in the details. This iBrief highlights the flawed reasoning underlying Brulotte as evidenced by its application in Scheiber, but ultimately concludes that overruling the case may be of little help to Mr. Scheiber in his suit against Dolby
A Distributed Economics-based Infrastructure for Utility Computing
Existing attempts at utility computing revolve around two approaches. The
first consists of proprietary solutions involving renting time on dedicated
utility computing machines. The second requires the use of heavy, monolithic
applications that are difficult to deploy, maintain, and use.
We propose a distributed, community-oriented approach to utility computing.
Our approach provides an infrastructure built on Web Services in which modular
components are combined to create a seemingly simple, yet powerful system. The
community-oriented nature generates an economic environment which results in
fair transactions between consumers and providers of computing cycles while
simultaneously encouraging improvements in the infrastructure of the
computational grid itself.Comment: 8 pages, 1 figur
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