Tsunami impacts on shallow groundwater and associated water supply on the East Coast of Sri Lanka: a post-tsunami well recovery support initiative and an assessment of groundwater salinity in three areas of Batticaloa and Ampara Districts

Groundwater, Aquifers, Salinity, Natural disasters, Water supply, Drinking water, Wells, Rehabilitation, Mosquitoes, Disease vectors, Environmental Economics and Policy, Health Economics and Policy, Resource /Energy Economics and Policy,

ESTIMATION OF LIQUID EMISSION LOADS FROM INDUSTRIES WITHIN THE KELANI RIVER BASIN

The Kelani River could be ranked as the largest recipient of industrialeffluents of the country. The pollution burden of this effluent is quite diverseranging from food manufacturing industries to heavy industrial dischargesfrom textile factories, tanneries, soap and cleaning preparationsmanufacturing plants and rubber factories. An attempt was made to estimatethe liquid emission loads released annually into the Kelani River Basin by theabove sectors.Liquid emission loads were assessed in terms of Biological Oxygen Demand(BOD) and Total Suspended Solid (TSS) content. In certain cases specialparameters such as Chemical Oxygen Demand (COD) and Chromium werealso assessed because of chemical contamination and hazardous potential. Inestimating emission loads Rapid Assessment Procedure and the Date BadeUrban Pollution Control Model were used as the guide.The results of the study indicate that the Kelani River receives 766.73 tons ofBOD and 462.04 tons of TSS annually from the above mentioned industrialsectors and 3.8 million cubic meters of annual industrial wastewater volume.In addition, the tanneries and leather finishing factories discharge untreatedeffluent, which is contaminated with chromium, a hazardous heavy metalhaving bioaccumulation potential, into the river basin. The amount ofchromium released into the river is as high as 6.36 tons while the COD loadfrom rubber manufacturing sector is 48.71 tons annually

ASSESSMENT OF THE COMPOSITION AND THE VOLUME OF BIOGAS LIBERATION FROM AGRICULTURAL WASTES

Study was conducted in the Faculty of Agriculture, University of Ruhuna, Mapalana toassess the composition and the volume of biogas liberation pattern from differentagricultural raw materials.In the Sri Lankan batch type biogas generator (volume 6m\ first batch of straw (lOOOkg)was filled in September 1999 and second and third batch in October 2000, April 2001respectively. It was revealed that average gas production from the digester was 1.0 m3/daywith a peak value of 1.8m3/day. Total gas production during four and half month period ofdigestion was 166.85 m3. The maximum average methane percentage and the average lagphase during the digestion were 50% and 20 days respectively.In order to assess the biogas liberation pattern and composiuon of each material, alaboratory test unit was designed using a 20 L plastic gallon as the digester andexperiment was conducted using straw, cow dung and market garbage (vegetable) as rawmaterials. Gas volumes, pH value of slurry and methane percentage were measured whilemaintaining the temperature between 35°C-37°C using electric bulbs.N,P,K compositions, CIN ratio and dry matter percentages of different raw materials wereanalyzed. Total biogas liberated per unit weight of dry matter was 8.15 L, 58.7 Land15.797L for dung, vegetable and straw respectively. The duration of digestion period was55-60 days. Average methane percentages of the liberated gases were 53%, 54% and 50%for dung, vegetable and straw respectively. It was revealed that market garbage had thehighest digestibility value, which had the highest gas production with high methanepercentage.

Objective validation of central sensitization in the rat UVB and heat rekindling model

Background: The UVB and heat rekindling (UVB/HR) model shows potential as a translatable inflammatory pain model. However, the occurrence of central sensitization in this model, a fundamental mechanism underlying chronic pain, has been debated. Face, construct and predictive validity are key requisites of animal models; electromyogram (EMG) recordings were utilized to objectively demonstrate validity of the rat UVB/HR model. Methods: The UVB/HR model was induced on the heel of the hind paw under anaesthesia. Mechanical withdrawal thresholds (MWTs) were obtained from biceps femoris EMG responses to a gradually increasing pinch at the mid hind paw region under alfaxalone anaesthesia, 96 h after UVB irradiation. MWT was compared between UVB/HR and SHAM-treated rats (anaesthetic only). Underlying central mechanisms in the model were pharmacologically validated by MWT measurement following intrathecal N-methyl-d-aspartate (NMDA) receptor antagonist, MK-801, or saline. Results: Secondary hyperalgesia was confirmed by a significantly lower pre-drug MWT {mean [±standard error of the mean (SEM)]} in UVB/HR [56.3 (±2.1) g/mm(2) , n = 15] compared with SHAM-treated rats [69.3 (±2.9) g/mm(2) , n = 8], confirming face validity of the model. Predictive validity was demonstrated by the attenuation of secondary hyperalgesia by MK-801, where mean (±SEM) MWT was significantly higher [77.2 (±5.9) g/mm(2) n = 7] in comparison with pre-drug [57.8 (±3.5) g/mm(2) n = 7] and saline [57.0 (±3.2) g/mm(2) n = 8] at peak drug effect. The occurrence of central sensitization confirmed construct validity of the UVB/HR model. Conclusions: This study used objective outcome measures of secondary hyperalgesia to validate the rat UVB/HR model as a translational model of inflammatory pain

Can Laminated Carbon Challenge Gold? Toward Universal, Scalable, and Low-Cost Carbon Electrodes for Perovskite Solar Cells

While perovskite solar cell (PSC) efficiencies are soaring at a laboratory scale, these are most commonly achieved with evaporated gold electrodes, which would present a significant expense in large-scale production. This can be remedied through the use of significantly cheaper carbon electrodes that, in contrast to metals, also do not migrate through the device. To this end, the present work investigates simple-to-prepare aluminum-supported carbon electrodes derived from commercially available, inexpensive materials that can be applied onto various hole-transporting materials and enable photovoltaic performances on par with those provided by gold electrodes. Successful integration of the new carbon-based electrode into flexible devices produced by a roll-to-roll printing technology by both pressing and lamination is demonstrated. However, temperature cycling durability tests reveal that the use of carbon electrodes based on commercial pastes is hindered by incompatibility of adhesive additives with the key components of the PSCs under heating. Resolving this issue, tailor-made graphite electrodes devoid of damaging additives are introduced, which improve the PSC stability under temperature cycling test protocol to the level provided by benchmark gold electrodes. The study highlights current challenges in developing laminated carbon electrodes in PSCs and proposes strategies toward the resolution thereof.This work was funded by the Australian Centre for Advanced Photovoltaics and Australian Renewable Energy Agency. A.N.S. also acknowledges the financial support from the Australian Research Council (Centre of Excellence CE140100012; Future Fellowship FT200100317). Monash Centre for Electron Microscopy (MCEM) and Melbourne Centre for Nano fabrication (MCN) are acknowledged for providing access to their facilities. The authors are grateful to Dr T. Zhang, A. Surmiak, Dr. N. Peris, Dr. D. Senevirathna, and Dr. N. Pai from Monash University for the experimental support throughout this study

Hydrogeological condition and groundwater quality distribution in the tsunami affected Southern coastal area of Sri Lanka

Groundwater monitoring in the tsunami affected southern coastal Weligama bay area was conductedduring May 2005 to July 2006 to determine the hydrogeological conditions and groundwater quality byselecting 90 dug wells where water level, electrical conductivity (EC), total dissolved solids (TDS)and pH was measured in monthly interval. The Weligama bay area is located in latitudes and longitudesof 80°22', 5°97'. The dug wells are sunk into the permeable quaternary sand deposits in the coastalmargin at Weligama Bay area is very permeable and-hydro-geological conditions are very favorablefor saltwater intrusion.The study helped to prepare groundwater isograph map and the distribution ofEC, TDS and pH mapsusing the GIS package MAPINFO. Groundwater isograph map help to identify groundwater distributionof the coastal area of Weligama. There exist a closed relationship between topographical map &groundwater contour map.The results of the study revealed that the Electrical conductivity of well water in all wells situated inthe Tsunami affected Zone are turned to be saline (EC in average increases from 150011 Siemens perem to around 4000 ~l siemens /cm.). According to the hydrographs prepared during the study period,unconfined quaternary aquifer ground water level intimately related to atmospheric precipitation. Thecharacteristic of the hydrograph provides a conclusion, that the recharge of unconfined ground waterin quaternary aquifer takes place during the period of monsoon rain and quality of ground water dueto tsunami has not changed specially.

Human stomach microbiota: Effects on health and disease

The gut microbiota is a complex ecological community, consisting of trillions of microbes which include bacteria, viruses, fungi and protozoa. The stomach was previously considered as a sterile site uninhabited by microbes due to its hostile environmental conditions. Breaking this concept, Helicobacter pylori was the first pathogen reported to inhabit the stomach. Recent studies have suggested that the stomach harbours transient as well as certain commensal bacterial and fungal species. The five major microbial phyla in the stomach have been identified as Firmicutes, Bacteroidetes, Actinobacteria, Fusobacteria and Proteobacteria. The composition of gastric microbiota is dynamic and is affected by several factors.  These include age group, dietary habits, medication use, inflammation of gastric mucosa and H. pylori colonization.  Further, the role of host genetics has recently been studied in maintaining the stomach microbiota. Mutations in host genes may affect the host’s immune response towards commensal bacteria and reduce their number and diversity. The essential multiple roles of gut microorganisms include maintaining homeostasis in the gut, contributing to immune function and extraction of nutrients and energy from our diets.  Loss of the normal balance between the gut microbiota and host has been associated with several abnormal conditions and disorders such as obesity, malnutrition, inflammatory bowel diseases (IBD), neurological disorders, and cancer. In the stomach, the interaction between H. pylori and the gastric microbiota can also influence gastric dis­ease progression. Further studies should focus on addressing the role of gastric dysbiosis in health and disease. Identifying gastric microbiota is essential to understand how the gut microbiota and H. pylori affect health and disease.</p

Upper limb muscle strength and endurance in Chronic Obstructive Pulmonary Disease

Introduction: Skeletal muscle weakness is an overlooked effect of chronic obstructive pulmonarydisease (COPD).Objectives: In this case-control study we compared skeletal muscle strength and endurance of a groupof patients with COPD with a comparable group of healthy volunteers.Methods: Upper limb muscle strength and endurance of 18 males and 12 females from a medical clinicof a tertiary care hospital with diagnosed COPD was measured by a handgrip dynamometer usingprescribed protocol and was compared with muscle strength and endurance of 30 healthy age, genderand body mass index (BMI) matched volunteers. Patients with concomitant severe cardiac, neurologicaland rheumatological conditions were excluded. Data were analyzed using SPSS version 16. Two sampleT-test was used to identify the statistical significance.Results: There was no significant difference in BMI of cases and controls (males mean BMI: cases19.8kgm2, controls 20.4kgm2; p = 0.73; females mean BMI: cases 20.4kgm2, controls 18.6kgm2; p =0.19). Muscle strength and endurance were significantly lower in cases when compared with controls,both in males (mean muscle strength: cases 19.8kg, controls 29.3kg, p<0.001. mean endurance: cases80.6s, controls 190.2s, p<0.001) and females (mean muscle strength; cases 11.8kg, controls 23.3kg,p<0.001, mean endurance: cases 49.3s, controls 111.3s, p<0.001).Conclusions: In this study a population of patients with COPD had significantly lower muscle strengthand endurance. Since muscle weakness contributes to poor ventilation and quality of life, programmesto improve muscle strength and endurance should be considered in the management of COPD

An audit of specimens received for superficial fungal studies to the Department of Microbiology, University of Ruhuna

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Towards Digital Thinking and Practices: Experiences of Sri Lankan Teachers and Students

Commonwealth Digital Education Leadership Training in Action (C-DELTA), an open and free online programme of the Commonwealth of Learning, provides a framework to foster digital education. The Open University of Sri Lanka implemented an intervention during 2020-2021 to promote digital education in Sri Lankan secondary schools, through the adoption of C-DELTA. This paper presents how C-DELTA supported developing digital thinking and practices among teachers and students, challenges faced and supports received by them, and impacts of the intervention. Participants’ experiences were captured through questionnaire surveys, concept maps, focus group interviews, reflective stories, and video narratives. The findings revealed that the intervention has enhanced developing digital learning skills of teachers and students, and changing their thinking and practices, yet, amid various challenges. While the implementation of C-DELTA in schools has been slow during the COVID-19 pandemic, the pandemic itself has shown the significance of improving digital literacy and digital practices