To predict the potential severity of outbreaks of infectious diseases such as SARS, HIV, TB and smallpox, a summary parameter, the basic reproduction number R(0), is generally calculated from a population-level model. R(0) specifies the average number of secondary infections caused by one infected individual during his/her entire infectious period at the start of an outbreak. R(0) is used to as...

Control of the 2002-2003 severe acute respiratory syndrome (SARS) outbreak was based on rapid diagnosis coupled with effective patient isolation. We used uncertainty and sensitivity analysis of the basic reproductive number R0 to assess the role that model parameters play in outbreak control. The transmission rate and isolation effectiveness have the largest fractional effect on R0. We estimate...

OBJECTIVE To assess the effect of R0 resection margin status and R0 en bloc resection in pancreatoduodenectomy outcomes. DESIGN Retrospective medical record review. SETTING Mayo Clinic, Rochester, Minnesota. PATIENTS Patients who underwent pancreatoduodenectomy for pancreatic adenocarcinoma at our institution between January 1, 1981, and December 31, 2007, were identified and their medica...

In this paper we consider the inventory problem with backorder such that both order and total demand quantities are triangular fuzzy numbers Q̃ = (q1, q0, q2), and R̃ = (r1, r0, r2) respectively, where q1 = q0−Δ1, q2 = q0+Δ2,r1 = r0−Δ3, r2 = r0+Δ4 such that 0 < Δ1 < q0, 0 < Δ2, 0 < Δ3 < r0, 0 < Δ4. Let s denote the maximum inventory quantity. Under conditions s ≤ q1 < q0 < q2 < r1 < r0 < r2, we f...

Clustering of cosmic-ray sources affects the flux observed beyond the cutoff imposed by the cosmic microwave background and may be important in interpreting the AGASA, Fly’s Eye, and HiRes data. The standard deviation, σ, in the predicted number, N , of events above 10 eV is σ/N = 0.9(r0/10Mpc) 0.9, where r0 is the unknown scale length of the correlation function (r0 ≃ 10 Mpc for field galaxies...

A parameterized model of the mass distribution within the Milky Way is fitted to the available observational constraints. Constraints at R < R0 and at R ≃ R0 are well satisfied, while those at 1 < R/R0 <∼ 2 cannot be adequately fitted with the consequence that the circular speed vc(R) at R > R0 is extremely uncertain. The most important single parameter is the ratio of the scale length Rd,∗ of ...

This paper focuses on a fundamental input parameter for most existing mathematical models of pandemic influenza, the ‘basic reproductive number R0,’ defined to be the mean number of new influenza infections created by a newly infected person in a population of all susceptible people. We argue that R0 is limited in policy and scientific value as is any single parameter attempting to characterize...

I reconsider the problem of the Newtonian limit in nonlinear gravity models in the light of recently proposed models Lgrav ∼ √−gf(R) with inverse powers of R. Expansion around a maximally symmetric local background with curvature scalar R0 > 0 gives the correct Newtonian limit on length scales ≪ R 0 if the gravitational Lagrangian √−gf(R) satisfies |f(R0)f (R0)| ≪ 1, and I propose two models wi...