Use of seasonal climate information to predict coconut production in Sri Lanka

Accurate forecasting of annual national coconut production (ANCP) is important for national agricultural planning and negotiating forward contracts. Climate and the long-term trends (attributed to 'technology') are major factors that determine ANCP. The effect of climate on ANCP of the following year was studied for the seven agro-ecological regions (AER's) in the principal coconut growing areas for the period 1950-2002. Climate was studied based on seasons aggregated by the monsoon calendar and by quarters that are consistent with the agricultural calendar. The use of quarterly seasons explained more of the variability of ANCP than the use of monsoon based seasons. January-March rainfall in all AER's and July-September rainfall in the wetter regions are positively correlated with the ANCP (p < 0.005). The technology effect was estimated using a log-linear trend model. The regression model integrates both climate and technology effects developed to predict ANCP with high fidelity (R2 = 0.94). The climate effect was estimated by regressing production data that had been de-trended to remove the technology effects with quarterly rainfall in the year prior to harvest. The most significant predictors were found to be the quarterly rainfall from the AER's in the coconut growing regions that are designated as wet and intermediate. Representative rainfall from each quarter was used in a regression model with corrections for the technology effect. The correlation between observed and predicted values of the ANCP was 0.83 (p < 0.001). The prediction of ANCP for 2003 and 2004 gave errors of only 6.5 and 7.0%. The estimated value of ANCP for 2005 is 2715 million nuts, which is 12% higher than the mean. The lead time of the prediction extends to 15 months but it may be extended with the use of seasonal climate forecasts to 24 months

Economic Value of Climate Variability Impacts on Coconut Production in Sri Lanka

This paper assesses the economic value of climate variability, employing a percentile analysis on an array of 31-years national annual coconut production data from 1971 to 2001. Of the production array, 10% and 90% percentiles have been considered respectively as lower and upper production extremes. The 60% of production departures of each year of extremes with respect to the mean production of 10% to 90% percentile were attributed to climate variability because studies show that the 60% of the variation of coconut production is explained by climate. These production deviations were then valued multiplying by free-on-board (FOB) prices of fresh coconuts. Results show that the foregone income from coconuts due to low rainfall varied between US$32 million to US$ 73 million while the incremental coconut income in crop glut extremes due to high rainfall varied between US$42 million and US$ 87 million. Results show that the climate variability causes income losses to the economy estimated at US$32 million to US$ 73 million in years of extreme crop shortage. And in years of extreme crop surplus, the economy realises income gains of US$42 million to US$ 87 million. These indicate the potential for significant economic benefits from investments in adaptations that would reduce variability in nut production which is caused by variations in climate. Further work is however needed to estimate the effectiveness and economic benefits that might be achieved from investments in adaptation

Use of gas liquid chromatography in combination with pancreatic lipolysis and multivariate data analysis techniques for identification of lard contamination in some vegetable oils

A study was conducted to investigate the use of gas liquid chromatography (GLC) to identify lard (LD) contamination in palm oil (PO), palm kernel oil (PKO), and canola oil (CLO). Vegetable oils were deliberately adulterated with animal fats such as LD, beef tallow (BT), and chicken fat (CF) in varying proportions. In order to monitor the fatty acid (FA) compositional changes due to adulteration, GLC analyses of fatty acid methyl esters (FAME) were performed on 2-monoacylglycerol (2-MG) and neutral triacylglycerol (TAG) isolated from each sample. For the evaluation of FA data, multivariate statistical techniques were employed. The results showed that canonical discriminant (CANDISC) analysis was the most effective technique for discriminating LD-adulterated samples from those adulterated with other animal fats. Additionally, mathematical equations obtained by simple regression analysis could be used for quantification of LD contents in admixtures

Viscous Fluids and Gauss-Bonnet Modified Gravity

We study effects of cosmic fluids on finite-time future singularities in modified $f(R,G)$-gravity, where $R$ and $G$ are the Ricci scalar and the Gauss-Bonnet invariant, respectively. We consider the fluid equation of state in the general form, $\omega=\omega(\rho)$, and we suppose the existence of a bulk viscosity. We investigate quintessence region ($\omega>-1$) and phantom region ($\omega<-1$) and the possibility to change or avoid the singularities in $f(R,G)$-gravity. Finally, we study the inclusion of quantum effects in large curvatures regime.Comment: 14 page

Quantum corrections to the inflaton potential and the power spectra from superhorizon modes and trace anomalies

We obtain the effective inflaton potential during slow roll inflation by including the one loop quantum corrections to the energy momentum tensor from scalar curvature and tensor perturbations as well as quantum fluctuations from light scalars and light Dirac fermions generically coupled to the inflaton. During slow roll inflation there is a clean and unambiguous separation between superhorizon and subhorizon contributions to the energy momentum tensor. The superhorizon part is determined by the curvature perturbations and scalar field fluctuations: both feature infrared enhancements as the inverse of a combination of slow roll parameters which measure the departure from scale invariance in each case.Fermions and gravitons do not exhibit infrared divergences. The subhorizon part is completely specified by the trace anomaly of the fields with different spins and is solely determined by the space-time geometry. The one-loop quantum corrections to the amplitude of curvature and tensor perturbations are obtained to leading order in slow-roll and in the (H/M_PL)^2 expansion. This study provides a complete assessment of the backreaction problem up to one loop including bosonic and fermionic degrees of freedom. The result validates the effective field theory description of inflation and confirms the robustness of the inflationary paradigm to quantum fluctuations. Quantum corrections to the power spectra are expressed in terms of the CMB observables:n_s, r and dn_s/dln k. Trace anomalies (especially the graviton part) dominate these quantum corrections in a definite direction: they enhance the scalar curvature fluctuations and reduce the tensor fluctuations.Comment: 18 pages, no figure

Correlation of influenza infection with glycan array

Poster Presentation: SPB1 / SPB2 - Virus Host Interaction/Pathogensis/Transmission: abstract no. B109PINTRODUCTION: The past 6 years has seen the introduction of glycan arrays containing large numbers of sialic acid (Sia) containing compounds and these arrays have been used to demonstrate the relative binding affinity of influenza viruses to different glycans. Though infor...postprin

Cosmological perturbations from varying masses and couplings

We study the evolution of perturbations during the domination and decay of a massive particle species whose mass and decay rate are allowed to depend on the expectation value of a light scalar field. We specialize in the case where the light field is slow-rolling, showing that during a phase of inhomogeneous mass-domination and decay the isocurvature perturbation of the light field is converted into a curvature perturbation with an efficiency which is nine times larger than when the mass is fixed. We derive a condition on the annihilation cross section and on the decay rate for the domination of the massive particles and we show that standard model particles cannot dominate the universe before nucleosynthesis. We also compare this mechanism with the curvaton model. Finally, observational signatures are discussed. A cold dark matter isocurvature mode can be generated if the dark matter is produced out of equilibrium by both the inflaton and the massive particle species decay. Non-Gaussianities are present: they are chi-square deviations. However, they might be too small to be observable.Comment: 21 pages, 4 figures, published versio

Quintessentially Flat Scalar Potentials

Both inflationary and quintessence cosmologies require scalar fields which roll very slowly over cosmological time scales, and so typically demand extremely flat potentials. Sufficiently flat potentials are notoriously difficult to obtain from realistic theories of microscopic physics, and this poses a naturalness problem for both types of cosmologies. We propose a brane-world-based microscopic mechanism for generating scalar potentials which can naturally be flat enough for both types of cosmological applications. The scalars of interest are higher-dimensional bulk pseudo-Goldstone bosons whose scale of symmetry breaking is exponentially suppressed in the higher-dimensional theory by the separation between various branes. The light scalars appear in the effective 4D theory as pseudo-Goldstone bosons. Since naturalness problems are more severe for quintessence models, motivated by our construction we explore in more detail the possibilities for using pseudo-Goldstone bosons to build quintessence models. Depending on how the cosmological constant problem is solved, these models typically imply the universe is now entering a matter-dominated oscillatory phase for which the equation of state parameter w = p/rho oscillates between w = 1 and w = -1.Comment: 27 pages, LaTeX, 5 figures using epsfig, uses JHEP

A single residue substitution in the receptor-binding domain of H5N1 hemagglutinin is critical for packaging into pseudotyped lentiviral particles

© 2012 Tang et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Serological studies for influenza infection and vaccine response often involve microneutralization and hemagglutination inhibition assays to evaluate neutralizing antibodies against human and avian influenza viruses, including H5N1. We have previously characterized lentiviral particles pseudotyped with H5-HA (H5pp) and validated an H5pp-based assay as a safe alternative for high-throughput serological studies in BSL-2 facilities. Here we show that H5-HAs from different clades do not always give rise to efficient production of H5pp and the underlying mechanisms are addressed. Methodology/Findings: We have carried out mutational analysis to delineate the molecular determinants responsible for efficient packaging of HA from A/Cambodia/40808/2005 (H5Cam) and A/Anhui/1/2005 (H5Anh) into H5pp. Our results demonstrate that a single A134V mutation in the 130-loop of the receptor binding domain is sufficient to render H5Anh the ability to generate H5Anh-pp efficiently, whereas the reverse V134A mutation greatly hampers production of H5Cam-pp. Although protein expression in total cell lysates is similar for H5Anh and H5Cam, cell surface expression of H5Cam is detected at a significantly higher level than that of H5Anh. We further demonstrate by several independent lines of evidence that the behaviour of H5Anh can be explained by a stronger binding to sialic acid receptors implicating residue 134. Conclusions: We have identified a single A134V mutation as the molecular determinant in H5-HA for efficient incorporation into H5pp envelope and delineated the underlying mechanism. The reduced binding to sialic acid receptors as a result of the A134V mutation not only exerts a critical influence in pseudotyping efficiency of H5-HA, but has also an impact at the whole virus level. Because A134V substitution has been reported as a naturally occurring mutation in human host, our results may have implications for the understanding of human host adaptation of avian influenza H5N1 virusesThis work was supported by grants from the Research Fund for the Control of Infectious Diseases of Hong Kong (RFCID#08070972), the Area of Excellence Scheme of the University Grants Committee (grant AoE/M-12/-06 of the Hong Kong Special Administrative Region, China), the French Ministry of Health, and the RESPARI project of the Institut Pasteur International Network

Immunohistochemical detection of Claudin low breast cancer; which subcellular level to be assessed?

Objectives: Claudin low breast cancers are often high grade, triple negative tumours with poor prognosis.  They are identified at genetic level and are not diagnosed routinely by immunohistochemistry. The objective was to determine the best subcellular level to detect Claudin low breast cancer by immunohistochemistry, in terms of their histopathological prognostic features.Methods: This cross sectional study included all archival breast cancer tissue collected up to December 2015 in our unit. Tissue microarrays (TMA) were constructed using 23 breast cancer cores with a diameter of 2mm, in each TMA. TMAs were immunohistochemically stained for Claudin 3 expression and was scored as; no staining=0, weak staining=1, moderate staining=2 and strong staining=3, separately for membrane, cytoplasmic and nuclear staining. A score <2 was considered Claudin low and analysed against the histopathological prognostic features of the breast cancer.Results: A total of 546 breast cancers were assessed. Claudin low expression was identified at cytoplasmic, membrane and nuclear level in 74.9%, 74.5% and 42% of breast cancers respectively. Low nuclear expression of Claudin 3 was associated with high grade (p=0.028), Nottingham Prognostic Index of >3.4 (p=0.028), ER and PR negative (p<0.001) and HER 2 negative (p=0.013) tumours while low membrane staining was associated with low grade (p=0.038), HER 2 negative (p<0.001) breast cancers. Low cytoplasmic staining was associated with HER 2 negative breast cancer only (p=0.002).Conclusions: Nuclear staining for Claudin should be assessed to identify Claudin low breast cancer by immunohistochemistry as it significantly associates with most of the Claudin low breast cancer characteristics