Arboricultural Assessment of Street Trees in Colombo City, Sri Lanka

Roadside trees are beneficial for providing ecological services, such as heat absorbance, natural air conditioning, and reducing GHG emissions in urban landscapes. This study examines the tree structure, species composition, species diversity, and some field observations (i.e. tree structural defects and disorders) on roadside trees in Colombo City. The vegetation parameters, such as diameter-at-breast height (DBH), tree height, and crown radius were measured in each tree. Purposive random sampling was adapted to invent street trees along High-level Road (Nugegoda to Tummulla junction), Bauddhaloka Mawatha (Tummulla junction to Borella Cemetery junction),Viharamahadevi Park circle and suburbs, Ananda Coomaraswamy Mawatha-Sri Jayawardanapura Mawatha (Kollupitia to Rajagiriya), Jawatta Road, Torinton Avenue and Keppitipola road. A total of 1458 street trees belonging to 92 species, 71 genera and 33 families were recorded along the roadways of Colombo City expanding ca. 20 km in length. Average 41±18 trees were located per kilometer. The survey shows that 64% of the species were exotic and 36% were indigenous species, reflecting the trend towards planting more exotic tree species in streets in recent past. The most dominant street trees were Albizia saman [% Relative Density (RD)=8; % Relative Basal Area (RBA)=34, % Relative Crown Cover (RCC)=30] and Peltophorum pterocarpum [% RD=11; % RBA=16; % RCC=19]. The highest number of trees was recorded from Public Library to Town Hall via Anagarika Dharmapala Mawatha (69 trees/km and 36 spp./km) and the most diverse tree species composition was found along Marcus Fernando Mawatha (66 trees/km and 52 spp./km) at Viharamahadevi Park circle. In conclusion, maintaining urban forest inventories, silvicultural managing of street trees from Ficus invasion, and introducing suitable native trees viz., Lagerstroemia speciose (Murutha), Pongamia pinnata (Magul-Karanda), Barringtonia asiatica (Mudilla) and Phyllanthus emblica (Nelli) for future tree planting areas will be recommended.Keywords: Street trees, Forest inventory, Silvicultural management, Colombo cit

Structural insights into the catalysis and regulation of E3 ubiquitin ligases

Covalent attachment (conjugation) of one or more ubiquitin molecules to protein substrates governs numerous eukaryotic cellular processes, including apoptosis, cell division and immune responses. Ubiquitylation was originally associated with protein degradation, but it is now clear that ubiquitylation also mediates processes such as protein–protein interactions and cell signalling depending on the type of ubiquitin conjugation. Ubiquitin ligases (E3s) catalyse the final step of ubiquitin conjugation by transferring ubiquitin from ubiquitin-conjugating enzymes (E2s) to substrates. In humans, more than 600 E3s contribute to determining the fates of thousands of substrates; hence, E3s need to be tightly regulated to ensure accurate substrate ubiquitylation. Recent findings illustrate how E3s function on a structural level and how they coordinate with E2s and substrates to meticulously conjugate ubiquitin. Insights regarding the mechanisms of E3 regulation, including structural aspects of their autoinhibition and activation are also emerging

Multidrug efflux pumps:structure, function and regulation

Infections arising from multidrug-resistant pathogenic bacteria are spreading rapidly throughout the world and threaten to become untreatable. The origins of resistance are numerous and complex, but one underlying factor is the capacity of bacteria to rapidly export drugs through the intrinsic activity of efflux pumps. In this Review, we describe recent advances that have increased our understanding of the structures and molecular mechanisms of multidrug efflux pumps in bacteria. Clinical and laboratory data indicate that efflux pumps function not only in the drug extrusion process but also in virulence and the adaptive responses that contribute to antimicrobial resistance during infection. The emerging picture of the structure, function and regulation of efflux pumps suggests opportunities for countering their activities

Molecular mechanisms of reversing neural degeneration by retinoic acid, a major derivative of vitamin A

For the past hundred years since the discovery of vitamin A, the field of research associated with retinoids has been well evolved due to advances in molecular biology, chemistry, biochemistry and medicine. Vitamin A is an essential component in diet. Major derivatives of vitamin A such as retinol, retinaldehydes and retinoic acid are collectively considered as retinoids. Deficit of Vitamin A has a direct correlation with disease development in our body emphasizing the importance of retinol. Retinoic Acid is proclaimed as powerful mitogen acting in our body since the developmental embryonic stages where it is associated with many organ systems in body carrying out different functionalities. Retinoids carry out many functions of nervous systems. This review is mainly focused on contribution of Retinoic acid towards reversing the process of neural degeneration in pathological conditions achieved by neurodegenerative diseases and tumor inducing situations. Retinoids can act on neurons carrying morphogenesis of nerves by promoting stem cell differentiation. Activation of phospholipase A2 pathway can promote neural differentiation. Also by inactivating human Inhibitor of DNA binding 2 gene, retinols can suppress stem cell proliferation and initiate morphogenesis. This gene inactivation can be also used as a therapy to prevent malignant cell proliferation leading to tumors. Anti amyloidogenic activity is discussed in this review locates a significant importance in reversing neural degenerating process in diseased conditions. Moreover, Reactive Oxygen Species accumulation can be suppressed by Retinoic Acid where it can promote cell survival during pathological constrains. The revision of literature is carried out in depth revealing Retinoic Acid related putative drug target mechanisms, where we can use Retinoic Acid as a novel therapeutic drug in neurodegenerative diseases

Assessment of the contents of a selected macro, micro and toxic elements in ripen bael fruits and tender shoots of water spinach and sweet potato using XRF and ICP-MS methods

Macro and micro elemental nutrient profiles and compositions of toxic heavy metals in food items are important attributes in culinary and nutrition sciences. We selected ripen bael fruits of elite accessions selected for large-scale cultivation in Sri Lanka, Kankong, a green leafy vegetable prone to bioaccumulation of toxic heavy metals (market and commercially available samples) and shoot-tops of sweet potato, an underutilized leafy vegetable to detect the elemental compositions using X-ray fluorescence (XRF) and Inductive Coupled Plasma Mass Spectrometric (ICP-MS) methods. Bael pulp was extracted from ripe fruits and, Kankong and sweet potato shoot-tops were collected. The presence and absence of elements were assessed using XRF. The elemental contents were measured using ICP-MS, and statistically analyzed. Bael and SP samples did not contain toxic heavy metals As and Pb whereas Kankong samples collected from a municipal wastewater drain contained all these toxic elements in large quantities. Kankong samples purchased from open market contained Hg, Cd, As and Cr. It is also noted that Pb separately correlated with Cr, Fe, Co, Zn, Ni and Hg contents in Kankong implying that they are under a common absorption mechanism or coming from a common source in the polluted habitat. The present study concludes that Kankong in Sri Lanka is unsafe for consumption and SP is an alternative to replace Kankong

Phylogeographic and phylogenetic analyses of selected set of wild and naturalized <em>Solanum</em> spp. in Sri Lanka

Solanum spp. encompass a greater share of the biodiversity in the world. Sri Lanka, one of the biodiversity hotspots in the world, is the home for wide range of Solanum spp. which have been named and morphologically characterized.However, their origins and times of origin have not yet been resolved. Hence, this study was conducted to identify the origins and origination events of 13 wild and naturalized Solanum spp. found in Sri Lanka, using DNA barcoding locus matK in comparison to worldwide Solanum spp. with phylogenetics and divergence dating approaches. In this study, 13 Sri Lankan Solanum spp. were separated into four defined phylogenetic groups viz., Old world, Morelloids, Acanthophora and Trova. The studied Sri Lankan Solanum spp. would have been originated in Africa 2.007 million years ago (MYA) in the Pleistocene epoch through mammalian migration from Mediterranean land bridges. The Australian relatives of Sri Lankan Solanum spp. would have been colonized from South Asia through South East Asia. The floristic connectivity in Pleistocene epoch may have introduced Asian Solanum spp. to South East Asia where mid Miocenic collisions between Australian and Asian plates as well as over water Long Distance Dispersal (LDD) may have caused these species to colonize in Australia. Our analysis demonstrated that most of the Solanum spp. found in Sri Lanka were introduced from India during the Pleistocene ice age. We suggest that Pre Pleistocene migrations of Solanum spp. such as S. nigrum may have occurred through overwater LDD

MEC-RHA:demonstration of novel service request handling algorithm for MEC

Abstract Multi-Access Edge Computing (MEC) is a cloud computing evolution that delivers end-user services at the mobile network’s edge. As a result, MEC guarantees that users will benefit from ultra-low latency and increased bandwidth when using the services. The orchestration process is the holistic management and control of the edge computing platforms. Handling of service requests forwarded by the MEC subscribers is an inceptive function that requires the intervention of the orchestrator. This paper demonstrates how an advanced service request handler algorithm (MEC-RHA) works on MEC orchestration, considering factors of service priority levels, feasibility, and resource availability when launching a service; while an optimal MEC server selection process is formed based on those factors