ARBUSCULAR MYCORRHIZAL ASSOCIATION IN SOME SELECTED DRY FOREST SPECIES AT BUNDALA NATIONAL PARK, SRI LANKA

The vegetation of dry forests at Bundala National Park, Sri Lanka is under a threat due tothe invasion of alien exotic species and poor natural forest regeneration. Since it isimportant to understand the effects of soil microorganisms in sustainable forestmanagement, this study attempts to find out how the mycorrhizal infections would favourdry forest plant species for their growth and survival. Fine lateral roots of seven naturalforest species (Cassia auriculata, Drypetes sepiaria, Dichrostachys cineria, Securenigaleucopyros, Salvadora persica, Zyzyphus oenoplia, Manilkara hexandra) and twoinvasive species (Opuntia dillenii, Prosopis juliflora) were collected from BundalaNational Park and examined for mycorrhizal infection in two different times (wet anddry) of the year. Processing and staining of root samples were carried out using themodified Philips and Heyman (1970) method.Muscular mycorrhizal infections were detected in fine lateral roots of all the studiedspecies except in Manilkara hexandra. Percentage infection of mycorrhizae in dry andwet periods was significantly different. There was an increased mycorrhizal infection inCassia auriculata, Drypetes septaria, Opuntia dillenii and Prosopis juliflora in the dryseason compared to the wet season and this would facilitate the absorption of water andphosphorus by these species and thereby help them to grow and compete with other plantspecies successfully. A non-cyst forming nematode has been identified in the xylem offine roots of Manilkara hexandra and this may be the reason for the die-back of matureindividuals of the species in the area during the drought periods.

Predictive coupled-cluster isomer orderings for some Sin{}_nCm{}_m (m,n≤12m, n\le 12) clusters; A pragmatic comparison between DFT and complete basis limit coupled-cluster benchmarks

The accurate determination of the preferred ${\rm Si}_{12}{\rm C}_{12}$ isomer is important to guide experimental efforts directed towards synthesizing SiC nano-wires and related polymer structures which are anticipated to be highly efficient exciton materials for opto-electronic devices. In order to definitively identify preferred isomeric structures for silicon carbon nano-clusters, highly accurate geometries, energies and harmonic zero point energies have been computed using coupled-cluster theory with systematic extrapolation to the complete basis limit for set of silicon carbon clusters ranging in size from SiC$_3$ to ${\rm Si}_{12}{\rm C}_{12}$. It is found that post-MBPT(2) correlation energy plays a significant role in obtaining converged relative isomer energies, suggesting that predictions using low rung density functional methods will not have adequate accuracy. Utilizing the best composite coupled-cluster energy that is still computationally feasible, entailing a 3-4 SCF and CCSD extrapolation with triple-$\zeta$ (T) correlation, the {\it closo} ${\rm Si}_{12}{\rm C}_{12}$ isomer is identified to be the preferred isomer in support of previous calculations [J. Chem. Phys. 2015, 142, 034303]. Additionally we have investigated more pragmatic approaches to obtaining accurate silicon carbide isomer energies, including the use of frozen natural orbital coupled-cluster theory and several rungs of standard and double-hybrid density functional theory. Frozen natural orbitals as a way to compute post MBPT(2) correlation energy is found to be an excellent balance between efficiency and accuracy

An Investigation into the effect of monocultural plantation of eucalyptus camaldulensis on soil fertility status

The effect of Eucalyptus camaldulensis monoculture on soil fertility statusin the dry zone was studied comparatively with another monoculture of Tectonagrandis and a naturalforest located in the same area over a period of 5 months.Total litter production of Eucalyptus was 370.68 kglha as compared with1349.07 kglha in Tectona grandis (study period overlapped the leaf senescence)and 217.75 kglha in the natural forest. Litter decomposition was 40.22% inEucalyptus while it was 40.27% and 44.95% in naturalforest, and Tectona respectively.Nutrient release to litter at the time of fall did not differ between thevegetation types. However, it differed between the tree components and nutrients,the orders being leaves>twigs>bark and N>P>K>Ca.Significant differences (p;;;::0.05)were seen in moisture content, pH, organicmatter content, total nitrogen percentage, available potassium and calcium betweenthe soils in the vegetation types

DIVERSITY OF TERRESTRIAL FERN SPECIES IN A SUBMONTANE SECONDARY FOREST AT UPPER HANTANA

Although there are many fern species at the secondary forest of Upper Hantana area, theirdistribution and the diversity has not been studied adequately. In the Upper Hantana areamany of the habitats are under threat due to human activities and therefore, most of thesefern species are at a risk. Therefore, it is very importarit to conserve these fern species andfor this purpose, it is necessary to identify all the ferns in the area and their distribution.The objectives of this study were to find out the fern diversity in the Upper Hantana areaand to find out microhabitat requirements of these fern species.Forty-five, 2x4cm2 quadrates were established at different sites i.e, at the roadside,streamside and in the forest interior of the study site. All the fern species in these quadrateswere identified and recorded.Results revealed that the species, genera and family diversities were high at Upper Hantanaarea. A total of 29 species belonging to 17 genera and 13 families were recorded from thearea. Out of 29 species 53% were recorded from roadside while 34% and 17% wererecorded from streamside and forest interior respectively. With respect to the 13 familiesrecorded 48% were found at roadside, 35% from the streamside and 17% from the forestinterior.As there were more fern species at roadside, these may easily be disturbed with increasedhuman activities.

Pediatric cancer care in Africa: SIOP Global Mapping Program report on economic and population indicators

Introduction Inalignment with the World Health Organization (WHO) Global Initiative for Childhood Cancer (GICC), the International Society of Pediatric Oncology initiated a program to map global pediatric oncology services. As survival rates in Africa are low and data are scant, this continent was mapped first to identify areas with greatest need. Methods Beginning November 2018, an electronic survey was sent to all known stakeholders, followed by email communications and internet searches to verify data. Availability of pediatric oncologists, chemotherapy, surgical expertise, and radiotherapy was correlated with geographic region, World Bank income status, Universal Health Coverage, population < 15 and < 24 years, percentage of gross domestic product spent on healthcare, and Human Development Index (HDI). Results Responses were received from 48/54 African countries. All three treatment modalities were reportedly available in 9/48 countries, whereas seven countries reported no pediatric oncology services. Negative correlations were detected between provision of all three services and geographic region (P = 0.01), younger median population age (P = 0.002), low-income country status (P = 0.045), and lower HDI (P < 0.001). Conclusion This study provides a comprehensive overview of pediatric oncology care in Africa, emphasizing marked disparities between countries: some have highly specialized services, whereas others have no services. A long-term strategy to eliminate disparities in African pediatric cancer care should be aligned with the WHO GICC aims and facilitated by SIOP Africa. Meeting abstracts SIOP maps pediatric oncology services in Africa to address inequalities in childhood cancer services. Geel J, Ranasinghe N, Davidson A, Challinor J, Howard S, Wollaert S, Myezo K, Renner L, Hessissen L, Bouffet E. 51st Annual Congress of the International Society of Paediatric Oncology (SIOP), Lyon, France, October 2019. Pediatric Blood and Cancer Vol 66 S219-S219. Pediatric cancer care in Africa: SIOP Global Mapping Program report on economic and population indicators

Design and Implementation of a Web Application for an E-Plant Store

With the advancement of technology in every industry, finding items with a few clicks is now simpler. Most people do not have enough knowledge about planting and its advantages of it. Therefore, this platform will be very helpful for those who sell and buy plants. Customers cannot compare prices or pay online when it comes to markets or plant nurseries. So, in this case, Plantae.lk offers various opportunities to customers. They can inspect, get details, compare plants’ pricing, and make online payments easily. In this competitive business world, customer satisfaction is extremely important. We want each customer to have a pleasant shopping experience. With that intention, customer support service offers technical advice and guidance when it is needed. This web application also consists of detailed gardening advice. The major goal of this web application is to provide a better business experience for both seller and consumer.([1])([2]

The Information Geometry of the Ising Model on Planar Random Graphs

It has been suggested that an information geometric view of statistical mechanics in which a metric is introduced onto the space of parameters provides an interesting alternative characterisation of the phase structure, particularly in the case where there are two such parameters -- such as the Ising model with inverse temperature $\beta$ and external field $h$. In various two parameter calculable models the scalar curvature ${\cal R}$ of the information metric has been found to diverge at the phase transition point $\beta_c$ and a plausible scaling relation postulated: ${\cal R} \sim |\beta- \beta_c|^{\alpha - 2}$. For spin models the necessity of calculating in non-zero field has limited analytic consideration to 1D, mean-field and Bethe lattice Ising models. In this letter we use the solution in field of the Ising model on an ensemble of planar random graphs (where $\alpha=-1, \beta=1/2, \gamma=2$) to evaluate the scaling behaviour of the scalar curvature, and find ${\cal R} \sim | \beta- \beta_c |^{-2}$. The apparent discrepancy is traced back to the effect of a negative $\alpha$.Comment: Version accepted for publication in PRE, revtex