1,629 research outputs found
Climate Change, Its Implications for Agriculture and Rural Development in Nigeria
This study identified the indicators of climate change both anthropogenic and natural variability which affect agriculture and rural development in Oji River Local Government Area of Enugu State, Nigeria. A structured interview schedule was used in sourcing information from sixty farmers. Data obtained were analysed using descriptive statistics. The following indicators of climate change affected agricultural and rural development; early on set of rainfall and early ceasation, early on set of rainfall and late ceasation, late on set of rainfall and late ceasation, late on set of rainfall and early cessation, above normal rainfall, below normal rainfall, longer than normal rainfall, shorter than normal rainfall, high intensity rainfall, irratic/torrential rainfall, flash flooding, rainstorms, coastal flooding, gustiness, erosion/flooding, rivers and streams overflowing their banks, unusual patterns of precipitation, high sunshine intensity, early on set and early ceasation of harmattan, late on set and early ceasation of harmattan, irratic wind, high speed wind, frequency of clement weather, constant draught, rising temperature, high humidity, presence and incidence of unfamiliar pests and diseases
Shear Stress Measurements of Non-Spherical Particles in High Shear Rate Flows
The behavior of liquid-solid flows varies greatly depending on fluid viscosity; particle and liquid inertia; and collisions and near-collisions between particles. Shear stress measurements were made in a coaxial rheometer with a height to gap ratio (b/r0) of 11.7 and gap to outer radius ratio (h/b) of 0.166 that was specially designed to minimize the effects of secondary flows. Experiments were performed for a range of Reynolds numbers, solid fractions and ratio of particle to fluid densities. With neutrally buoyant particles, the dimensional shear stress exhibits a linear dependence on Reynolds number: the slope is monotonic but a non-linear function of the solid fraction. Though non-neutrally buoyant particles exhibit a similar linear dependence at higher Reynolds numbers, at lower values the shear stress exhibits a non-linear behavior in which the stress increases with decreasing Reynolds number due to particle settling
Southern Gals / music by Albert Gumble; words by Jack Yellen
Cover: a drawing of a woman with Hat; photo inset of Florence Moore; Publisher: Jerome H. Remick and Co. (Detroit)https://egrove.olemiss.edu/sharris_c/1133/thumbnail.jp
Alexander\u27s Band is Back in Dixieland / music by Albert Gumble; words by Jack Yellen
Cover: African American band parading in uniform; Publisher: Jerome H. Remick and Co. (New York)https://egrove.olemiss.edu/sharris_c/1157/thumbnail.jp
Relativistic Green's function approach to charged-current neutrino-nucleus quasielastic scattering
A relativistic Green's function approach to inclusive quasielastic
charged-current neutrino-nucleus scattering is developed. The components of the
hadron tensor are written in terms of the single-particle Green's function,
which is expanded on the eigenfunctions of the nuclear optical potential, so
that final state interactions are accounted for by means of a complex optical
potential but without a loss of flux. Results for the (neutrino_mu, mu-)
reaction on 16O and 12C target nuclei are presented and discussed. A reasonable
agreement of the flux-averaged cross section on 12C with experimental data is
achieved.Comment: 7 pages, 4 figure
Effective Action and Schwinger Pair Production in Scalar QED
Some astrophysical objects are supposed to have very strong electromagnetic
fields above the critical strength. Quantum fluctuations due to strong
electromagnetic fields modify the Maxwell theory and particularly electric
fields make the vacuum unstable against pair production of charged particles.
We study the strong field effect such as the effective action and the Schwinger
pair production in scalar QED.Comment: RevTex 6 pages, no figure; Proceedings of APCTP Winter School on
Black Hole Astrophysics 2008, Jan 24-29, 200
Variation in host susceptibility and infectiousness generated by co-infection: the myxoma–Trichostrongylus retortaeformis case in wild rabbits
One of the conditions that can affect host susceptibility and parasite transmission is the occurrence of concomitant infections. Parasites interact directly or indirectly within an individual host and often these interactions are modulated by the host immune response. We used a free-living rabbit population co-infected with the nematode Trichostrongylus retortaeformis, which appears to stimulate an acquired immune response, and the immunosuppressive poxvirus myxoma. Modelling was used to examine how myxoma infection alters the immune-mediated establishment and death/expulsion of T. retortaeformis, and consequently affects parasite intensity and duration of the infection. Simulations were based on the general TH1–TH2 immunological paradigm that proposes the polarization of the host immune response towards one of the two subsets of T helper cells. Our findings suggest that myxoma infections contribute to alter host susceptibility to the nematode, as co-infected rabbits showed higher worm intensity compared with virus negative hosts. Results also suggest that myxoma disrupts the ability of the host to clear T. retortaeformis as worm intensities were consistently high and remained high in old rabbits. However, the co-infection model has to include some immune-mediated nematode regulation to be consistent with field data, indicating that the TH1–TH2 dichotomy is not complete. We conclude that seasonal myxoma outbreaks enhance host susceptibility to the nematode and generate highly infected hosts that remain infectious for a longer time. Finally, the virus–nematode co-infection increases heterogeneities among individuals and potentially has a large effect on parasite transmission
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