a Department of Geological Sciences, University of North Carolina at Chapel Hill, 104 South Rd., Mitchell Hall, CB #3315, Chapel Hill, NC 27599-3315, USA b Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road, NW, Washington, DC 20015-1305, USA c Department of Geosciences, University of Arizona, 1040 E. 4th Street, Tucson, AZ 85721, USA d Department of G...

Address correspondence to: Tyler M. Sharp, PhD, Centers for Disease Control and Prevention Dengue Branch, 1324 Calle Cañada, San Juan, PR 00920. Email: [email protected] Dengue represents an increasingly important public health challenge in Puerto Rico, with recent epidemics in 2007, 2010, and 2012–2013. Although recent advances in dengue vaccine development offer hope for primary prevention, the ...

This paper empirically examines the role of social networks in welfare participation. Social theorists from across the political spectrum have argued that network e ects have given rise to a culture of poverty. Empirical work, however, has found it di cult to distinguish the e ect of networks from unobservable characteristics of individuals and areas. We use data on language spoken to better in...

This Working Paper should not be reported as representing the views of the IMF. The views expressed in this Working Paper are those of the author(s) and do not necessarily represent those of the IMF or IMF policy. Working Papers describe research in progress by the author(s) and are published to elicit comments and to further debate. This paper assesses the relative efficiency and flexibility o...

The occurrence of unilateral flagellar phase variation was previously demonstrated in Escherichia coli strains carrying the non-fliC flagellin-specifying locus flk. In this study, we investigated the mechanism involved in this process. By using sequencing and sequence analysis, the flk region between the chromosomal genes yhaC and rnpB was characterized in all described flk-positive E. coli str...

Time Limits: The Effects on Welfare Use and Other Consumption-Smoothing Mechanisms We use data from the Survey of Income and Program Participation covering the period 19892006 to investigate the impact that time limits on receipt of Temporary Assistance for Needy Families have on female-headed family outcomes, including welfare use, employment and living arrangements. The effects of time limits...