Diversity of Actinomycetes in Nitrogen Fixing Root Nodules of Casuarinaequisetifolia and its Impact on Plant Growth

Casuarinaequisetifolia (Kasa) is an actinorhizal plant which is used for rehabilitation of poor and disturbed soil throughout the world. Actinorhizal plants which were colonized by Frankia sp. enhance the soil fertility due to frankial colonization in root nodules. However, few studies were reported on non-frankial colonization and its impact on plant growth and soil fertility. Thus this study was carried out to investigate the unrevealed information on actinomycete consortia residing the nitrogen fixing root nodules of C. equisetifolia. The actinomycete were successfully isolated from surface sterilized root nodules by using double layered agar plate technique and also isolates were tested on reinfectivity on Casuarina seedlings. Three different actinomycetes were able to identify as Frankia sp., Micromonospora sp., and novel symbiont as Streptomyces sp. from nitrogen fixing root nodules of Casuarina plants. Further, co-existence of all threeisolates were observed in nitrogen free and nitrogen enriched Yeast Mannitol Agar medium (YMA). Frankia sp. promoted the shoot and root growth by 87% and 55% respectively with nodulation of C. equisetifolia and whereas Micromonospora sp. promoted the root and shoot growth by 28% without nodulation. In contrast Streptomyces sp. was able to trigger the lateral root formation of C. equisetifolia which indicate the ability of the microorganism to alter host development system. This study provides novel data on root inhabiting Streptomyces sp. which could play a vital role in enhancing plant growth, exchanging complex signals between plant and microorganisms. These results suggest that the root inhabiting microbial consortium of C. equsetifolia would significantly contribute to the development of plant growth

Attitudes of Undergraduates towards Improving English Language Skills and Influence on Business Productivity: A Case Study of Faculty of Applied Sciences, USJP.

AbstractMany large and medium scale businesses operating in Sri Lanka at present have a global aspiration. Even if a company has a domestic focus, the employee base may comprise of individuals from different ethnic and cultural backgrounds. Moreover, with globalization having gathered pace, the customers being those from around the world and different language originations is often inevitable and beyond the control of a business entity. Hence, there is an immense significance in the use of a common language in business interactions. English is used as a lingua franca among most of the business communities today. In this regard, it is a pre-requisite for potential employees in similar contexts to have English language competency.However, a considerable percentage of the Sri Lankan undergraduates, who will soon become internal stakeholders of various businesses have a tendency to lack the desired level of English language skills. Assessing the attitudes of undergraduates is vital in this regard. This study aims at understanding the perceptions of the undergraduates towards improving their English language skills exploring the views and practices of the undergraduates of the Faculty of Applied Sciences in the University of Sri Jayewardenepura. The study obtained primary data via observations and a questionnaire survey; a statistical analysis was carried out to analyze any gaps in the attitudes of the undergraduates. Detailed findings of the study are discussed in the research paper. The analysis revealed a clear excuse-making attitude among the undergraduates. This gap in their attitudes needs to be closed and their minds need be nurtured to achieve enhanced business productivity in the future through an employee base with improved linguistic capacity.Keywords: Business Productivity, English, Common Language, Attitudes, Undergraduate

Differential modulation of microglia superoxide anion and thromboxane B(2 )generation by the marine manzamines

BACKGROUND: Thromboxane B(2 )(TXB(2)) and superoxide anion (O(2)(-)) are neuroinflammatory mediators that appear to be involved in the pathogenesis of several neurodegenerative diseases. Because activated-microglia are the main source of TXB(2 )and O(2)(- )in these disorders, modulation of their synthesis has been hypothesized as a potential therapeutic approach for neuroinflammatory disorders. Marine natural products have become a source of novel agents that modulate eicosanoids and O(2)(- )generation from activated murine and human leukocytes. With the exception of manzamine C, all other manzamines tested are characterized by a complex pentacyclic diamine linked to C-1 of the β-carboline moiety. These marine-derived alkaloids have been reported to possess a diverse range of bioactivities including anticancer, immunostimulatory, insecticidal, antibacterial, antimalarial and antituberculosis activities. The purpose of this investigation was to conduct a structure-activity relationship study with manzamines (MZ) A, B, C, D, E and F on agonist-stimulated release of TXB(2 )and O(2)(- )from E. coli LPS-activated rat neonatal microglia in vitro. RESULTS: The manzamines differentially attenuated PMA (phorbol 12-myristate 13-acetate)-stimulated TXB(2 )generation in the following order of decreasing potency: MZA (IC(50 )<0.016 μM) >MZD (IC(50 )= 0.23 μM) >MZB (IC(50 )= 1.6 μM) >MZC (IC(50 )= 2.98 μM) >MZE and F (IC(50 )>10 μM). In contrast, there was less effect on OPZ (opsonized zymosan)-stimulated TXB(2 )generation: MZB (IC(50 )= 1.44 μM) >MZA (IC(50 )= 3.16 μM) >MZC (IC(50 )= 3.34 μM) >MZD, MZE and MZF (IC(50 )>10 μM). Similarly, PMA-stimulated O(2)(- )generation was affected differentially as follows: MZD (apparent IC(50)<0.1 μM) >MZA (IC(50 )= 0.1 μM) >MZB (IC(50 )= 3.16 μM) >MZC (IC(50 )= 3.43 μM) >MZE and MZF (IC(50 )>10 μM). In contrast, OPZ-stimulated O(2)(- )generation was minimally affected: MZB (IC(50 )= 4.17 μM) >MZC (IC(50 )= 9.3 μM) >MZA, MZD, MZE and MZF (IC(50 )> 10 μM). From the structure-activity relationship perspective, contributing factors to the observed differential bioactivity on TXB(2 )and O(2)(- )generation are the solubility or ionic forms of MZA and D as well as changes such as saturation or oxidation of the β carboline or 8-membered amine ring. In contrast, the fused 13-membered macrocyclic and isoquinoline ring system, and any substitutions in these rings would not appear to be factors contributing to bioactivity. CONCLUSION: To our knowledge, this is the first experimental study that demonstrates that MZA, at in vitro concentrations that are non toxic to E. coli LPS-activated rat neonatal microglia, potently modulates PMA-stimulated TXB(2 )and O(2)(- )generation. MZA may thus be a lead candidate for the development of novel therapeutic agents for the modulation of TXB(2 )and O(2)(- )release in neuroinflammatory diseases. Marine natural products provide a novel and rich source of chemical diversity that can contribute to the design and development of new and potentially useful anti-inflammatory agents to treat neurodegenerative diseases

INdigenous Systems and Policies Improved and Reimagined for Ear and hearing care (INSPIRE): A multi-method study protocol

Introduction Otitis media (middle ear disease) severity and chronicity among Aboriginal and Torres Strait Islander people, as well as gaps in socioeconomic outcomes related to hearing loss, indicates a breakdown in the current ear and hearing care system. The ear and hearing care system spans multiple sectors due to long-term impacts of otitis media and hearing loss in health, education and employment, necessitating a multi-disciplinary cross-sectorial approach to ear and hearing care. Public policies shape the current ear and hearing care system and here it is argued that a critical public policy analysis across different sectors is needed, with strong Aboriginal and Torres Strait Islander leadership and guidance. The current study aims to establish consensus-based ear and hearing care policy solutions for Aboriginal and Torres Strait Islander people in Australia. Methods and analysis This multi-method study will be guided by a Brains Trust with strong Aboriginal and Torres Strait Islander leadership. Public policies in hearing health, social services, and education will be scoped to identify policy gaps, using the World Health Organization framework. Qualitative data will be collected through a culturally specific process of yarning circles to identify policy challenges and/or limitations in enabling accessible ear and hearing care programs/services for Aboriginal and Torres Strait Islander people, using dimensions of Morestin's public policy appraisal tool as an interview guide for stakeholders. Themes from the yarning circles will be used to inform an expert Delphi process to establish consensus-based policy solutions for optimising the ear and hearing care system for Aboriginal and Torres Strait Islander people. Ethics and dissemination This study has approval from the Australian Institute of Aboriginal and Torres Strait Islander Studies Ethics Committee. Study findings will be disseminated to community through Brains Trust members and study participants, as well as through publications in peer-reviewed journals and research forum presentations

Using rapid damage observations for Bayesian updating of hurricane vulnerability functions: A case study of Hurricane Dorian using social media

Rapid impact assessments immediately after disasters are crucial to enable rapid and effective mobilization of resources for response and recovery efforts. These assessments are often performed by analysing the three components of risk: hazard, exposure and vulnerability. Vulnerability curves are often constructed using historic insurance data or expert judgments, reducing their applicability for the characteristics of the specific hazard and building stock. Therefore, this paper outlines an approach to the creation of event-specific vulnerability curves, using Bayesian statistics (i.e., the zero-one inflated beta distribution) to update a pre-existing vulnerability curve (i.e., the prior) with observed impact data derived from social media. The approach is applied in a case study of Hurricane Dorian, which hit the Bahamas in September 2019. We analysed footage shot predominantly from unmanned aerial vehicles (UAVs) and other airborne vehicles posted on YouTube in the first 10 days after the disaster. Due to its Bayesian nature, the approach can be used regardless of the amount of data available as it balances the contribution of the prior and the observations

Rubisco activity in Mediterranean species is regulated by the chloroplastic CO2 concentration under water stress

Water stress decreases the availability of the gaseous substrate for ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) by decreasing leaf conductance to CO2. In spite of limiting photosynthetic carbon assimilation, especially in those environments where drought is the predominant factor affecting plant growth and yield, the effects of water deprivation on the mechanisms that control Rubisco activity are unclear. In the present study, 11 Mediterranean species, representing different growth forms, were subject to increasing levels of drought stress, the most severe one followed by rewatering. The results confirmed species-specific patterns in the decrease in the initial activity and activation state of Rubisco as drought stress and leaf dehydration intensified. Nevertheless, all species followed roughly the same trend when Rubisco activity was related to stomatal conductance (gs) and chloroplastic CO2 concentration (Cc), suggesting that deactivation of Rubisco sites could be induced by low Cc, as a result of water stress. The threshold level of Cc that triggered Rubisco deactivation was dependent on leaf characteristics and was related to the maximum attained for each species under non-stressing conditions. Those species adapted to low Cc were more capable of maintaining active Rubisco as drought stress intensified