We present an extensive pseudospectral study of the randomly forced Navier-Stokes equation (RFNSE) stirred by a stochastic force with zero mean and a variance ∼ k 4−d−y , where k is the wavevector and the dimension d = 3. We present the first evidence for multiscaling of velocity structure functions in this model for y ≥ 4. We extract the multiscaling exponent ratios ζp/ζ2 by using extended self similarity (ESS), examine their dependence on y, and show that, if y = 4, they are in agreement with those obtained for the deterministically forced Navier-Stokes equation (3dNSE). We also show that well-defined vortex filaments, which appear clearly in studies of the 3dNSE, are absent in the RFNSE. PACS : 47.27.Gs, 47.27.Eq, 05.45.+b, 05.70.Jk Kolmogorov's classic work (K41) on homogeneous, isotropic fluid turbulence focussed on the scaling behavior of velocity v structure functions S p (r) = |v i (x + r) − v i (x)| p , where the angular brackets denote an average over the statistical steady state [1]. He suggested that, for separations r ≡ |r| in the inertial range, which is substantial at large Reynolds numbers Re and lies between the forcing scale L and the dissipation scale η d , these structure functions scale as S p ∼ r ζp , with ζ p = p/3. Subsequent experiments [2] have suggested instead that multiscaling obtains with p/3 > ζ p , which turns out to be a nonlinear, monotonically increasing function of p; this has also been borne out by numerical studies of the three-dimensional Navier-Stokes equation forced deterministically (3dNSE) at large spatial scales [2,3]. The determination of the exponents ζ p has been one of the central, but elusive, goals of the theory of turbulence. One of the promising starting points for such a theory is the randomly forced Navier-Stokes equation (RFNSE) [4][5][6], driven by a Gaussian random force whose spatial Fourier transform f (k, t) has zero mean and a covariancehere k, k ′ are wave numbers, t, t ′ times, i, j Cartesian components in d dimensions, and P ij (k) the transverse projector which enforces the incompressiblity condition. One-loop renormalization-group (RG) studies of this RFNSE yield [4,5] a K41 energy spectrum, namely, E(k) ∼ k 2 S 2 (k) ≡ k 2 |v(k)| 2 ∼ k −5/3 , if we set d = 3 and y = 4; this has also been verified numerically [6]. Nevertheless, these RG studies have been criticised for a variety of reasons [7,8] such as using a large value for y in a small-y expansion and neglecting an infinity of marginal operators (if y = 4). These criticisms of the approxima-tions used in these studies might well be justified; but they clearly cannot be used to argue that the RFNSE is in itself inappropriate for a theory of turbulence. It is our purpose here to check if, indeed, the RFNSE is a good starting point for such a theory. Specifically we want to test whether structure functions in the RFNSE display the same multiscaling as in the 3dNSE for some value of y; if they do, then we can argue that both equations are in the same universality class and the RFNSE can, defensi...

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African swine fever (ASF) is one of the most important transboundary diseases of pigs. ASF has been identified in India for the first time in domestic pigs from outbreaks reported in two of the northeastern states, Arunachal Pradesh and Assam in 2020. A total of 11 ASF outbreaks in different regions killed over 3700 pigs and devastated the economy of small-scale livestock owners of both the states. Considering the first outbreak of ASF in India, a generic risk assessment framework was determined to identify potential risk factors that might favor future emergence of the disease. Based on the Indian scenario, we considered population density of host, farming practice, availability of biological vectors and wildlife reservoirs, epidemiological cycles, and international trade to analyze the possibility of future outbreaks of ASF and chances of establishment of endemism. On critical analysis of the identified risk factors associated with ASFV transmission, we observed that the risk factors are well preserved in the Indian geography and might participate in future outbreaks, further disseminating the disease to nearby countries. Since no vaccine is currently available against ASF, the domestic and the wild pigs (wild boars and the endangered pygmy hogs native to India) of this region are under constant threat of infection. For the near future, this region will have to continue to rely on the implementation of preventive measures to avoid the devastating losses that outbreaks can cause. The various adaptive control strategies to minimize the risks associated with the transmission of ASF, keeping our views to Indian settings, have been described. The risk-analysis framework presented in the study will give a further understanding of the dynamics of disease transmission and will help to design control strategies and corresponding measures to minimize the catastrophic consequences of ASF disease.

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Aims: To evaluate the role of the Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM), the Portsmouth variant (p-POSSUM) and the Glasgow Prognostic Score (GPS) in predicting outcome after pancreatic surgery with reference to the International Study Group of Pancreatic Surgery (ISGPS) definitions of post-pancreatectomy complications. Methods: All consecutive patients undergoing major pancreatic resection over a 32- month period were included. POSSUM, p-POSSUM and GPS score were calculated for each patient and correlated against the observed mortality and morbidity using the ISGPS definitions. Results: The observed:expected ratios for POSSUM mortality, POSSUM morbidity and p-POSSUM mortality were 0.24 (p < 0.0001), 0.86 (p < 0.0001) and 0.79 (p = 0.09), respectively. POSSUM had a ‘poor fit’ with respect to predicting morbidity (χ² = 16.4, 8 d.f., p = 0.04). Multifactorial regression analysis revealed the GPS as an independent predictor of post-operative outcome (GPS 1, p = 0.03, OR 2.99, 95% CI 1.4–7.9, and GPS 2, p = 0.02, OR 4.3, 95% CI 1.8–15.5). Conclusion: POSSUM has a limited role as an outcome score in pancreatic resection. The GPS may be a novel alternative to POSSUM as a pre-operative predictor of outcome.