Comparison of Filter Media for Wastewater Treatment by a Prototype Trickling Filter

The microbial process of wastewater treatment, attached growth, has significantly improved during recent years. Different filter media are used for microbial attached growth in trickling filters (TF) in the world. One of the main functions of filter media is the high surface area for the attachment of microorganisms to grow. Major wastewater treatment plants use stones as a medium for increasing the surface area in TFs. The proper grade of stone could not always be found within a reasonable distance from the wastewater treatment plant sites, significantly increasing transportation costs. Low-cost substitute materials, instead of stones, can reduce the cost of TF while increasing their treatment efficiency. This study attempted to use crushed waste polythene as a low-cost substitute material for stones. The objectives of this study were to evaluate the performance of prototype TF with crushed waste polythene and; to compare the treatment efficiency of two prototype TFs (with stone and with crushed waste polythene). Two prototype TFs were prepared using plastic barrels (250L) with two types of filter materials. The flow rate of the filters was 922mL/min and trickling filters were evaluated for two months for treatment efficiency. Water samples were taken before and after the trickling filter to determine the treatment efficiency. During the process of trickling filters, COD removal appeared to increase and it may be due to the adaptation of microbes to the new environment. The COD removal was comparatively higher in trickling filters with crushed polythene (62%) than in stones (42.6%). Almost similar results of pH and EC were found in both trickling filters. Total solids in treated wastewater were also almost similar in the two trickling filters. Based on the results of this study, it can be concluded that crushed polythene is a good alternative for stones in trickling filters.  Keywords: Crushed polythene, Filter material, Stone, Trickling filter, Wastewater&nbsp

Taxonomy and Systematic Analysis of the Two Genera Alpinia and Amomum of the Family Zingiberaceae in Sri Lanka

Alpinia and Amomum are the largest two genera that list the highest number of endemics offamily Zingiberaceae in Sri Lanka. The family is recognized as a least studied plant group inthe country, justifying the need for a thorough study. Hence, it is timely that the family istaken into consideration of molecular and systematic studies given new techniques areavailable. As a pioneering step, in this study, we addressed several taxonomic issues,phylogenetic relationships and conservational status of Alpinia and Amomum. In order tocollect more morphological data to address species boundaries with better insights, over 130morphological characters were studied and analysed using multivariate statistical methods.Molecular phylogenetic analysis was done using two Chloroplast gene regions (trnL-trnF andtrnS-trnfM). Results of the morphological analysis revealed the segregation of species ratherdepending on both vegetative and floral characters than only on floral characters. Study alsoidentified a group of Amomum with a new character combination which needs to berecognized as a new species or subspecies along with a new addition to genus Alpinia (A.zerumbet) in Sri Lanka. Furthermore, in our efforts to make a field key for easy identificationof species, results of this study also highlighted the difficulty in using only vegetativecharacters to differentiate species. Hence, the study has resulted in identifying a different andan easy set of morphological characters for species identification for Sri Lankan species.Evolutionary analysis of the two genera confirms that the Sri Lankan members of the twogenera Alpinia and Amomum have a monophyletic origin. Although the genus Alpinia has amonophyletic lineage, two members (A. abundiflora and A. fax) show a polytomy within thegenus. This was evident in both phylogenetic analysis and the morphological analysis.According to trnL-trnF and trnS-trnƒM data analysis, all the studied members of the genusAmomum have an exclusive monophyletic origin. Illumination of an immediate need forconservation efforts of these species is another important finding of the current study

FARMER ATTITUDES TOWARDS ADOPTION OF SUSTAINABLE PROTECTION TECHNOLOGIES: THE CASE OF INTEGRATED PEST MANAGEMENT IN VEGETABLE CULTIVATIONS IN SRI LANKA

This study examines empirically the extent to which vegetable cultivatingfarmers in Sri Lanka are willing to adopt effective, economical andsustainable crop protection technologies such as Integrated Pest Management(lPM) instead of applying solely chemical pesticides to control pests. It usesprimary data collected through a series of personnel interviews with arandomly selected sample of vegetable farmers (n = 100) that practicechemical control measures in the Kurunegala and Puttalam districts in theWayamba Province from May to July in 2005.The behavioural change in farmer attitudes and perceptions towards adoptionof environmentally-friendly IPM techniques instead of applying chemicals onthe vegetable cultivation on a regular basis were captured by means of twoindexes - Additive Index (AI) and a Multiplicative Index (MI), which usedthe scores given by participants to the survey to a set of attitudinal statements(n = 17) explaining this behaviour on a Likert scale. The outcome of AI andMI were in turn modelled with the farmer's socio economic characteristics,including the age, sex, level of education, income, managerial time,experience in farming, extent of land allocated for cultivation, crop type,availability of credit and extension facilities etc. to test significance of thesefactors on this behaviour. The results suggest that many of these have asignificant impact on the farmer's degree of responsiveness towards adoptionof sustainable agricultural practices. The outcome of analysis highlights theneed of provision of appropriate private and regulatory incentives for farmersto change their behaviour in this respect

Production characteristics and technical efficiency of buffalo farming in Thanamalwila veterinary division, Sri Lanka

Peer reviewe

A Comparative Study of Demand for Medical Care on Non Communicable Diseases: Western vs. Alternative

Medical care is an input to the production of health. People get treatment for their health issues under western medicine , complementary and alternative medicine. Western medicine can be identified as the most famous and modern medical care system in the world. Complementary and alternative medicine refers to avariety of health practices as ayurveda, homeopathy, acupuncture, herbs, yoga, etc . Considering Sri Lankan context, with the rapid increase of ageing population, there is a growing trend in non communicable diseases. Most of people tend to use these two systems to recover from non communicable diseases asasthma, cholesterol, hypertension, arthritis, etc. The main objective of this study was to distinguish between the demand for alternative medicine and western medicine related to non communicable diseases. It was considered socio demographic and economic factors for demand in medical care for both sectors. Primary data was based on Arogya private hospital and Siddhayurvedini private ayurvedic care institution in Gampaha. It was selected 100 non communicable disease patients using systematic sampling method. Logistic regression model was mainly used to distinguish between the alternative and western medical care. According to the findings of this study, females are more likely to demand for both medical cares. Middle age, unemployed, arthritis patient and duration of disease 2-5 years cause to raise demand for alternative medical care. Diabetic patient, employed, believing health status as serious and having employer provided insurance cause to raise demand for western medical care. Relative to the demand for alternative medical care, living in rural area and lower educated people are negatively associated with demand for western medical care.KEYWORDS: Demand, Western, alternative, non communicable disease

The first documentation of the immune response to cutaneous leishmaniasis caused by Leishmania donovani in Sri Lanka.

Introduction and Objectives: The predominant form of leishmaniasis seen in Sri Lanka is cutaneous leishmaniasis (CL) caused by Leishmania donovani, a species commonly causing visceral disease. The objective of this study was to explore the human host immune response to CL in Sri Lanka. Methods: A descriptive comparative study was carried out on nine CL patients referred to the Department of Parasitology, Faculty of Medicine, University of Peradeniya, Sri Lanka, during 2011-2013. mRNA was extracted from the skin biopsy samples and reverse transcribed to cDNA and tested for Th1 and Th2 cytokines by using specific primers for IFN-γ, IL-2 (Th1 cytokines) and IL-4, IL-10 (Th2 cytokines). The results were compared with different characteristics of the lesion (number, duration, size and type of lesion). Results: This study revealed that the majority of CL patients (5/9) elicited a Th1 response whereas a Th2 response was not detected in any of the patients. Of the Th1 cytokine positive patients, majority had single lesions, with a shorter duration and smaller sized lesions which were of the plaque type. Of those which exhibited a negative Th1 response, the majority were larger lesions with a longer duration and were of the papular-nodular type. Conclusions: The study suggests that the predominant immune response to CL caused by L. donovani in Sri Lanka, is a Th1 type of response which may explain the localization of L. donovani which is usually a viscerotropic species, to skin tissue. Limitations of study: This study was done only in nine patients due to resource limitations. A continuation of this study is indicated to validate these results.</p

Development of a seawater intrusion model for the Kalpitiya coastal aquifer in Sri Lanka

Seawater intrusion is the influx of saline water into freshwater aquifers leading to groundwater quality degradation. The Kalpitiya Coastal Aquifer (KCA) of Sri Lankan is a limestone aquifer and its’ adjacent groundwater is influenced by saline water. However, saltwater intrusion modeling has not been deeply investigated in coastal regions in the Sri Lankan context. Hence, this study aims to provide significant information to protect the KCA from contamination by seawater intrusion. A 3D variable-density groundwater flow model was used in this study to evaluate how far inland seawater has moved in the present and future situations. The model input parameters were chosen after reviewing geological records and permeability tests obtained from the National Water Resources Board, Sri Lanka. The numerical model for the pair density-dependent flow system was solved using the SEAWAT code. The estimated model was then run for the following 20 years (2016-2036) with the same hydrological parameters to assess the magnitude of seawater intrusion under four different scenarios (Scenario 1: no-change occurs in the model; Scenario 2: pumping from the aquifer increase by doubling in the same pumping wells; Scenario 3: three new agricultural wells will be opened within the second scenario; Scenario 4: change in the annual precipitation rate occurs (20% reduction of annual precipitation). Scenario 3 demonstrated that water pumping from agricultural wells may lead to reduce or reverse groundwater gradient. Overall, the modeled results depicted that the aquifer beneath the KCA is susceptible to increased groundwater pumpage. Therefore, the aquifer should be continuously monitored to determine the progress of seawater intrusion and suggest the best solutions to prevent the intrusion. As new data becomes available, the model should be modified to reduce the uncertainty in the simulations

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112