Trend of production and export of commercial crops of Vanuatu: 1991-2012

Agriculture is the mainstay of the rural population of Vanuatu. Obviously, improvements in crop production and exports will enhance standard of living of rural people and help support economic development. In Vanuatu beef, copra, cocoa and kava account for the bulk of export earnings. This study analysed trends in area, production and export of coconut, cocoa and kava crops during the 1991-2012 period. The study revealed that area under cocoa and kava crops has been declining during the study period, while the area under coconut crop was stagnant. The production of cocoa and kava showed negative trends. Copra production also showed a declining trend during the study period. Consequently, exports of cocoa and coconut products were declining during the reference period. However, exports of kava showed increasing trend but it also in the later part of the study period started declining. Evidently there is a positive relation between quantity of crop produced and exported. Vanuatu’s climate and land are conducive to produce these export-oriented crops, but detailed investigations are required to understand the problems and constraints faced by farmers in crop production, processing and export. In reversing the downward trend of agriculture export sector in Vanuatu, the integration of production and marketing will prove to be a crucial element of the agricultural development strategy

Large Scale Study of Ligand-Protein Relative Binding Free Energy Calculations: Actionable Predictions from Statistically Robust Protocols

The accurate and reliable prediction of protein-ligand binding affinities can play a central role in the drug discovery process as well as in personalized medicine. Of considerable importance during lead optimization are the alchemical free energy methods that furnish an estimation of relative binding free energies (RBFE) of similar molecules. Recent advances in these methods have increased their speed, accuracy, and precision. This is evident from the increasing number of retrospective as well as prospective studies employing them. However, such methods still have limited applicability in real-world scenarios due to a number of important yet unresolved issues. Here, we report the findings from a large data set comprising over 500 ligand transformations spanning over 300 ligands binding to a diverse set of 14 different protein targets which furnish statistically robust results on the accuracy, precision, and reproducibility of RBFE calculations. We use ensemble-based methods which are the only way to provide reliable uncertainty quantification given that the underlying molecular dynamics is chaotic. These are implemented using TIES (Thermodynamic Integration with Enhanced Sampling). Results achieve chemical accuracy in all cases. Ensemble simulations also furnish information on the statistical distributions of the free energy calculations which exhibit non-normal behavior. We find that the "enhanced sampling" method known as replica exchange with solute tempering degrades RBFE predictions. We also report definitively on numerous associated alchemical factors including the choice of ligand charge method, flexibility in ligand structure, and the size of the alchemical region including the number of atoms involved in transforming one ligand into another. Our findings provide a key set of recommendations that should be adopted for the reliable application of RBFE methods

Chemical Stabilisation of Sand : Part* II Construction and Studies of 50m X 4m Road

An experimental track (50m X 4m) was constructed on a loose sand bed by using two chemical-sand composition containing either 9 per cent urea formaldehyde (UF) resin or 11 per cent sodium silicate binder (on solid content basis). The trafficability studies on 5-6 cm thick stabilised track was found to vary from 1625 to 1700 psi in UF stabilised track and from 1340 to 1460 psi in silicate stabilised track. The effect of resin, desert environmental conditions and trafficability studies showed cumulative loss of load bearing capacity from 1625-1700 to 645-1125 psi

Comparison of Equilibrium and Nonequilibrium Approaches for Relative Binding Free Energy Predictions

Alchemical relative binding free energy calculations have recently found important applications in drug optimization. A series of congeneric compounds are generated from a preidentified lead compound, and their relative binding affinities to a protein are assessed in order to optimize candidate drugs. While methods based on equilibrium thermodynamics have been extensively studied, an approach based on nonequilibrium methods has recently been reported together with claims of its superiority. However, these claims pay insufficient attention to the basis and reliability of both methods. Here we report a comparative study of the two approaches across a large data set, comprising more than 500 ligand transformations spanning in excess of 300 ligands binding to a set of 14 diverse protein targets. Ensemble methods are essential to quantify the uncertainty in these calculations, not only for the reasons already established in the equilibrium approach but also to ensure that the nonequilibrium calculations reside within their domain of validity. If and only if ensemble methods are applied, we find that the nonequilibrium method can achieve accuracy and precision comparable to those of the equilibrium approach. Compared to the equilibrium method, the nonequilibrium approach can reduce computational costs but introduces higher computational complexity and longer wall clock times. There are, however, cases where the standard length of a nonequilibrium transition is not sufficient, necessitating a complete rerun of the entire set of transitions. This significantly increases the computational cost and proves to be highly inconvenient during large-scale applications. Our findings provide a key set of recommendations that should be adopted for the reliable implementation of nonequilibrium approaches to relative binding free energy calculations in ligand-protein systems

Strengthening governance of agriculture to enhance competitiveness of farmers in Pacific Islands countries

Effectiveness of governance and its regulatory quality matter for agricultural development in Pacific islands countries. Agriculture in these countries is important but is poorly developed and suffers due to weak agricultural institutions and governance issues. A stronger performing agriculture is crucial but its development depends on the enabling environment. There is need to facilitate the farmers by enhancing their competitiveness and bargaining power. Needed actions for strengthening the governance in PICs are: investment in rural and market infrastructures and services, ensuring quality of farm enterprises, strengthening the extension capabilities and promotion of regional brand for niche products

Pattern formation in Passiflora incarnata: An activator-inhibitor model

Based on a careful examination of the onset of violet colored dots along the filaments in the developing floral bud stage and the formation of alternating bands of violet and white color in the matured flowers of Passiflora incarnata (Passion flower), it is concluded that the pattern arises from a competition between the production of violet colored anthocyanin and the colorless flavonols along the filaments. The activator-inhibitor model of Gierer and Meinhardt along with the reaction diffusion theory of Turing is used to explain the formation of concentric rings in the flower

Vermicomposting of green Eucalyptus leaf litter by Eisenia foetida and Eudrilus eugenia

Effective clearance of different types of waste has become significant to sustain healthy environment. Vermicomposting has become a suitable substitute for the safe, hygienic and cost effective disposal of organic solid wastes. Earthworms decompose organic waste leading to the production of compost which is high in nutrient content. The present work has been designed to reveal competitive and / or beneficial interactions by studying the inter-specific interactions in terms of growth, maturation, survival and vermicomposting efficiency of two earthworm species Eisenia foetida and Eudrilus eugenia exposed to green leaf litter of Eucalyptus and measured physical variables during entire process. The complete process was taken fourteen weeks.Work was done in plastic beans in four set. 100 % cattle dung was also taken as a control. During the process following parameters viz. pH, temperature, biomass reduction and moisture content were analysed.pHof vermicomposting substrate was recorded low initially acidic but at last stage set in alkaline range. In case of temperature, it was changed 16-18°C ± 1°C from initial value. This was higher than control cattle dung (13°C± 1°C). Organic biomass was also depleted during process which was about 70-71 % ±1 % from initial level as compaired to cattle dung (46 %). Moisture content was lowerinitially then increased and set at high level

COMPARATIVE STUDIES OF COVID-19 IMPACT ON STUDENTS’ VIEWS ON DIGITAL HIGHER EDUCATION

Higher education sector has been significantly adapting to the new situation created by the COVID-19 pandemic. Despite students are often referred to, students are rarely at the centre of the concerns being raised. The research aim is to compare students’ views on digital higher education in light of COVID-19 underpinning the identification of issues in digital higher education in light of COVID-19. The research implies theoretical and empirical methods. The exploratory empirical study was carried out. Semi-structured interviews serves as the data collection method. Content analysis was applied to the obtained data for data processing. The theoretical analysis allows finding that digital environment in higher education is not limited by only a technical aspect of its organisation. Digital environment also implies students’ health, financial and economic situation, etc. The empirical findings contribute to the conclusion that digital higher education in light of COVID-19 is negatively evaluated by students. The most common issues faced by students are identified. The research question is newly formulated. Directions of further research are proposed. The novelty of the paper is presented by the identified issues in digital higher education in light of COVID-19.

Alchemical Free Energy Estimators and Molecular Dynamics Engines: Accuracy, Precision, and Reproducibility

The binding free energy between a ligand and its target protein is an essential quantity to know at all stages of the drug discovery pipeline. Assessing this value computationally can offer insight into where efforts should be focused in the pursuit of effective therapeutics to treat a myriad of diseases. In this work, we examine the computation of alchemical relative binding free energies with an eye for assessing reproducibility across popular molecular dynamics packages and free energy estimators. The focus of this work is on 54 ligand transformations from a diverse set of protein targets: MCL1, PTP1B, TYK2, CDK2, and thrombin. These targets are studied with three popular molecular dynamics packages: OpenMM, NAMD2, and NAMD3 alpha. Trajectories collected with these packages are used to compare relative binding free energies calculated with thermodynamic integration and free energy perturbation methods. The resulting binding free energies show good agreement between molecular dynamics packages with an average mean unsigned error between them of 0.50 kcal/mol. The correlation between packages is very good, with the lowest Spearman's, Pearson's and Kendall's tau correlation coefficients being 0.92, 0.91, and 0.76, respectively. Agreement between thermodynamic integration and free energy perturbation is shown to be very good when using ensemble averaging

Ensemble-Based Approaches Ensure Reliability and Reproducibility

It is increasingly widely recognized that ensemble-based approaches are required to achieve reliability, accuracy, and precision in molecular dynamics calculations. The purpose of the present article is to address a frequently raised question: what is the optimal way to perform ensemble simulation to calculate quantities of interest