No interactions for a collection of Weyl gravitons intermediated by a scalar field

The cross-couplings among several Weyl gravitons (described in the free limit by a sum of linearized Weyl actions) in the presence of a scalar field are studied with the help of the deformation theory based on local BRST cohomology. Under the hypotheses of locality, smoothness of the interactions in the coupling constant, Poincare invariance, (background) Lorentz invariance, and the preservation of the number of derivatives on each field, together with the supplementary assumption that the internal metric defined by the sum of Weyl lagrangians is positively defined, we prove that there are no consistent cross-interactions among different Weyl gravitons in the presence of a scalar field. The couplings of a single Weyl graviton to a scalar field are also discussed.Comment: 53 page

Effect of apical dominance on bud take in Citrus vegetative propagation

The objective of the study was to identify the grafting method, which will have a higher success rate of scion development. The study was conducted at Mount Makulu Central Research station in Chilanga, Zambia (15o33S / 28o11E) from April 2010 to November 2011. The study had 4 vegetative propagation methods that varied in the treatment of the rootstock and scion. The four methods were Standard T- budding (STB); Modified TBudding with decapitation (TBD); T- budding with scion bending (TBB); Crown grafting (CG). Bud take, shoot growth, leaf emergence and Leaf area index were measured up to 11 weeks after treatment (WAT). With CG there was 100 % bud take. STB had a bud take of 58.3 %. TBD had a bud take of 50 %. The lowest bud take percentage was recorded in TBB, which had a bud take of 41.7 %. At 5 weeks the STB and TBB treatment had shoot length of 0.7 and 1.0 cm respectively which were the shortest; this was followed by the CG treatment at 15.3 cm and the modified TBD with apical shoot decapitation (21.7 cm). STB shoots did not start growing until about 5 weeks, which was 2 weeks after the rootstock was cut off. At 5 weeks, the TBB and STB were yet to form leaves. The CG had close to 20 leaves and the TBD had almost 15.2 leaves. At the end of 11 weeks, the TBB had the highest number of leaves. Across the grafting methods; the Leaf area exhibited a pattern similar to leaf number; it kept on doubling every 2 weeks to until the 9th week after which the increase was negligible. At 11 weeks, the highest leaf area was in the TBD followed by the STB and lowest in the CG treatment.Int. J. Agril. Res. Innov. & Tech. 7 (1): 64-70, June, 201

A Long History of Low Productivity in Zambia: Is it Time to Do Away with Blanket Recommendations?

Although there have been calls to ramp up efforts to design and implement a fertiliser programme that recognises the spatial variability of soil fertility and climatic conditions in the country, Zambia like most countries in Africa, continues to rely heavily on outdated general fertiliser recommendations, which are uniform across geographic locations and crops. This could be one of the main reasons why Zambia continues to record low crop productivity despite government fertilizer subsidy programmes. Using soil analysis and household data collected in rural Zambia, this study presents a comparative analysis of location-specific fertilizer application versus blanket recommendation to demonstrate why it is important for the Zambian government to invest in area-specific fertiliser recommendations in order to raise crop productivity. As expected, the results show that soil fertility varies across the country. This was observed in all the mapped soil properties with ranges of 2.7 to 7.8 for soil pH, 0.08% to 10.1% for soil organic carbon and 1.0 ppm to 333.6ppm for soil Phosphorus. These values belong to different classes in terms of acidities and levels of adequacy and deficiency. These results indicate that blanket fertiliser recommendations, or even liming, may not be well suited across the entire country. Instead, they support the need for Zambia to promote area-specific fertiliser recommendations. It is recommended that soil testing be promoted as part of extension messages, and that the government’s Farmer Input Support Programme (FISP) should consider including soil testing as a requirement for the subsidy

A Long History of Low Productivity in Zambia: Is it Time to Do Away with Blanket Recommendations?

Although there have been calls to ramp up efforts to design and implement a fertiliser programme that recognises the spatial variability of soil fertility and climatic conditions in the country, Zambia like most countries in Africa, continues to rely heavily on outdated general fertiliser recommendations, which are uniform across geographic locations and crops. This could be one of the main reasons why Zambia continues to record low crop productivity despite government fertilizer subsidy programmes. Using soil analysis and household data collected in rural Zambia, this study presents a comparative analysis of location-specific fertilizer application versus blanket recommendation to demonstrate why it is important for the Zambian government to invest in area-specific fertiliser recommendations in order to raise crop productivity. As expected, the results show that soil fertility varies across the country. This was observed in all the mapped soil properties with ranges of 2.7 to 7.8 for soil pH, 0.08% to 10.1% for soil organic carbon and 1.0 ppm to 333.6ppm for soil Phosphorus. These values belong to different classes in terms of acidities and levels of adequacy and deficiency. These results indicate that blanket fertiliser recommendations, or even liming, may not be well suited across the entire country. Instead, they support the need for Zambia to promote area-specific fertiliser recommendations. It is recommended that soil testing be promoted as part of extension messages, and that the government’s Farmer Input Support Programme (FISP) should consider including soil testing as a requirement for the subsidy

Taylor dispersion with absorbing boundaries: A Stochastic Approach

We describe how to solve the problem of Taylor dispersion in the presence of absorbing boundaries using an exact stochastic formulation. In addition to providing a clear stochastic picture of Taylor dispersion, our method leads to closed-form expressions for all the moments of the convective displacement of the dispersing particles in terms of the transverse diffusion eigenmodes. We also find that the cumulants grow asymptotically linearly with time, ensuring a Gaussian distribution in the long-time limit. As a demonstration of the technique, the first two longitudinal cumulants (yielding respectively the effective velocity and the Taylor diffusion constant) as well as the skewness (a measure of the deviation from normality) are calculated for fluid flow in the parallel plate geometry. We find that the effective velocity and the skewness (which is negative in this case) are enhanced while Taylor dispersion is suppressed due to absorption at the boundary.Comment: 4 pages, 1 figur

Underreporting of side effects of standard first-line ART in the routine setting in Blantyre, Malawi

Introduction: In the Malawi ART programme, 92% of 250,000 patients are using the standard first-line regime of stavudine-lamivudine-nevaripine. National ART reports indicate <4% experience ART side effects, much less than expected from literature.Methods: We interviewed adult patients on standard first-line ART for at least one year, after routine visits to an urban clinic in Blantyre, Malawi. We determined the prevalence of symptoms that are common side-effects, described discrepancies between symptoms that patients reported to us and those that had been recorded by attending staff as side-effects in the point-of-care electronic monitoring system, and studied factors associated with such discrepancies.Results: Of 170 participants, 75 (44%) reported at least one symptom, most common were symptoms suggesting peripheral neuropathy (n=57) and lipodystrophy (n=16). Forty-six (66%) symptomatic patients said they reported symptoms to attending ART staff. Side-effects were recorded in the clinic database for just 4 patients. Toxicity recording was too low for meaningful analysis of factors associated with discrepancies between reporting and recording of side-effects. The prevalence of symptoms indicating characteristic side-effects of the standard first-line regimen was 39% based on interviews, and 2% in the electronic monitoring system. Conclusion: There was gross under-recording of side-effects in this setting, mainly due to not recording by ART staff. Pressure of work and insufficient perceived benefit of side-effect recording are suspected causes. Local and national ART reports do not reflect the true toxicity of the standard firstline regimen