iPURSE 2019

Permanent URI for this collectionhttps://ir.lib.pdn.ac.lk/handle/20.500.14444/37

Browse

Now showing 1 - 20 of 165

Developing a non host-specific biofertilizer: a microbial biofilm approach
(University of Peradeniya, Sri Lanka, 2019-09-12) Singhalage, I. D.; Seneviratne, G.; Madawala, H. M. S. P.
Host specificity of biofertilizers may pose several issues at large scale production and usage. The present study examined the universality of a fungal-bacterial biofilmed biofertilizer (BFBF) in comparison to its monoculture bacterial (BBF) and fungal (FBF) biofertilizers using three crops, Strawberry, Tomato and Rice. The BFBFs were formulated using strawberry (Fragaria ananassa) rhizosphere-associated bacterial (Enterobactor sp.) and fungal (Aspergillus sp.) strains. Strawberry, rice and tomato were grown in hydroponic medium with liquid biofertilizers (BFBF, BBF and FBF) applied at same ratio of biofertilizer: hydroponic medium in 1:9 ratio (in volume). A control was maintained in the hydroponic medium but without biofertilizers. The treatments were triplicated and arranged in a completely randomized design. The growth medium collected at different time intervals were analyzed for polysaccharides, amides and lipids by Fourier Transform Infra-red spectroscopy. Plant height and dry mass were recorded after a month. Data were analyzed by ANOVA and correlation. After 30 days, all crops showed significantly improved concentrations of polysaccharides, amides and fatty acids in media treated with BFBF, BBF and FBF over the control. The dry biomass and heights of strawberry and rice plants were significantly (p<0.05) higher in BFBF over the BBF, FBF and the control. In tomato, BFBF-treated seedlings also showed better growth, though not significantly. Concentrations of functional polysaccharides (14ᵗʰand 30ᵗʰdays), fatty acids (7ᵗʰand 14ᵗʰdays) and amides (30ᵗʰday) were positively and significantly correlated with the growth of strawberry plant. The growth of rice also showed a significant positive correlation with functional polysaccharides (14ᵗʰ day), fatty acids and amides (30ᵗʰday). In tomatoes, a significantly positive correlation was noted with the functional polysaccharides, fatty acids and amides after 30 days. The findings suggest that the BFBF developed from strawberry root-associated microbes nullify the general concept of crop specificity by potentially improving the growth of rice and tomato. As such, the BFBF seems to have a higher ability to improve the growth of crops in comparison to conventional monoculture biofertilizers.
Evaluation of Ground source cooling potential for Batticaloa, Sri Lanka
(University of Peradeniya, Sri Lanka, 2019-09-12) Suganya, E.; Ariyawansha, R. T. K.; Ganepitiya, G. G. S. M.; Basnayake, B. F. A.
Ground source for cooling has been identified as a promising technology in dry tropical regions. However, it is not popular in Sri Lanka. Therefore, this study was conducted to design a ground source cooling system that can be adopted in Batticaloa, Sri Lanka (Dry zone). The experiment was conducted during July and August, the hottest period of the year for Batticaloa. Thermocouples fixed to a data logger were installed into the soil to obtain the temperature profiles up to 7 m. It was found that the temperature did not vary below 2 m from the surface. The temperature at the water table depth of 7 m was 27 0C. In utilizing this information, the cooling load for a system was designed for a 3 m×3 m×3 m room with the occupation of four people and some electrical equipment. The calculations were based on thermal conductivity determined from experimental and standard values from literature. The highest ambient room temperature was considered as 40 ⁰C. Total cooling load approached a value of 5.2 kW to reduce and maintain the room temperature at 27 ⁰C. Water was used in the calculation as the heat-transfer medium of the system. It requires a flow rate of 2.48 × 10⁻⁴ m³/s with a pump rating of 24.33 W to maintain the required cooling load. It can be obtained from solar power. The copper tube selected for the design of heat exchanger has the dimensions of 0.9 cm inner and 1.14 cm outer diameters and best installed down to 7 m. Flat horizontal tubes are preferred to increase the contact surface area with soil and water filled pores. The application of Arduino-uno could increase the efficiency of the system by optimizing operating conditions. Coupling with pre-existing refrigeration system can boost the efficiency and demand where, we can have varying temperature according to the comfort preferences.
Processing of aromatic rice using 2-acetyle-1-pyrroline available in pandan (Pandanus amaryllifolius Roxb) leaves
(University of Peradeniya, Sri Lanka, 2019-09-12) Mayadunna, H. R. D. M.; Dharmasena, D. A. N.
Aromatic rice has a high demand and a premium price in the global market. The aromatic volatile chemical compound, 2-acetyl-1-pyrroline (2-AP) is, mainly responsible for the characteristic fragrance in aromatic rice. The aromatic essence 2-AP is found in Pandan leaves (Pandanus amaryllifolius Roxb) that are grown in tropical countries and commonly available in Sri Lanka. Fresh Pandan leaf has 10 times higher 2-AP than Basmati rice which contains around 1 ppm of 2-AP. This study was investigated the feasibility of transferring 2-AP available in Pandan leaves to non-aromatic short grain raw rice (BG- 360) for value addition. In order to increase the rice grain porosity to facilitate absorption of aroma, rice grains (BG-360) were vacuum dried (without soaking) to about 5% moisture at 70 ⁰C. 2-AP absorption was tested as direct leaf heating after mixing leaf with rice by microwave oven in a sealed chamber and using the ethanol extract of the chemical (2-AP). The microwaved treated rice samples were kept for three weeks for 2-AP absorption at room temperature. The ethanol extract treatment was tested for optimum absorption time to rice. Finally, raw rice, rice subjected to direct heating with leaf and treated with 2-AP extract were compared with premium quality Daawat Rozana Basmathi Rice by examining fragrance characteristics of treated raw and cooked rice using sensory panel. The results revealed that the best treatment for transferring 2-AP from leaf to raw rice is direct microwave heating of vacuum dried raw rice mixed with fresh Pandan leaves at a mass ratio of (leaves : rice) 1:10.
A review: fractionation methods of starch components (Amylose and Amylopectin) for industrial applications
(University of Peradeniya, Sri Lanka, 2019-09-12) Amaraweera, A. P. S. M.; Manipura, W. M. J. A. S. B.; Manamperi, W. A.; Gunathilake, C. A.
Starch is a natural polymer that can be used in industrial applications to prepare biodegradable artifacts. But these have many drawbacks such as high water absorption, low mechanical strength, and lesser durability. Properties of starch (chemical and physical) and that of the resultant applications are much dependent on the amylose to amylopectin ratio. Recent research studies have focused on fractionation of starch components and modifying the compositions of amylose and amylopectin for specific applications. Formulation of polymer blends with starch and various additives (cross linkers, plasticizers etc.) have led to significant improvements of properties in industrial applications such as plastics and composite material. This review mainly focuses on the recent developments in fractionation of starch using chemical, physical, and enzymatic methods. Of these, the physical and chemical fractionation methods are widely used, whereas enzymatic methods are used for highly specific applications. The main challenges of starch fractionation include high solubility and susceptibility to structural degradation. Recent studies have made significant progress in investigating various solvent mixtures and other process variables in order to overcome these challenges.
Migration framework for traditional web applications into CMS platform
(University of Peradeniya, Sri Lanka, 2019-09-12) Jayathilaka, G. A. S. C.; Arachchige, J. A.
Most of the organizations all over the world use web based information systems to operate their day-to-day activities. Due to the rapid changes of the organizational needs, the content inside these web applications are also increased agilely. Maintaining the increasing content while keeping consistency of the information is a challenging task. Content Management Systems (CMS) provide a platform to author the web information by different users of the system while maintaining the uniformity of the content. Therefore nowadays most of the web applications are moving to CMSs because of its easiness in developing and maintaining web systems. Starting the web development from the scratch in CSM platform requires immense effort for requirement gathering and information finding. Therefore migration of traditional web applications to CMS platform has been paid considerable attention. However very few researches focus on this migration process. The main objective of this research is providing a framework for migrating traditional web applications to CMS platform. The proposed framework provides a guided path for existing web applications to move into CMS. The framework is defined based on CMS Common Meta-Model which was proposed by V. de Castro et.al. in their research. A software tool was developed using Python, Java and Jython to automate the migration process. In the analysis of CMS Common Meta-Model few drawbacks were identified. Therefore the meta-model was extended to include dynamic ability of a web page. The results were validated with selected web sites with different technologies. The proposed framework provides an efficient way to compile web applications in CMS platform with web content of the traditional web site.
Enhancement of information security using music theory and attributes
(University of Peradeniya, 2019-09-12) Rukshani, P.; Sujatha, K.; Suthaharan, S. S.
The Internet is the fastest medium of information exchange. Internet and its technologies have replaced the traditional way of information exchange with the advancement of information and communication technology. In this electronic communication era, the demand for securing information exchange is highly needed and appreciated. Music and its attributes such as harmony, tone, pitch, and scales have been used in cryptography from the early days. Presently, music is vastly used in information hiding with the use of steganography. The art of encrypting and covering messages using music is termed as Musical Steganography. Further, musical notes and symbols have been used as codes and keys. The hiding is implemented by designing an algorithm for hiding a bit formatted message into music using its attributes before they encrypted into a format to transmit through Internet. In this paper, we propose an algorithm converts the bit into musical notes by mathematical properties. The sequence of musical notes generated for the particular bit sequence is a musical pattern. Particularly, a brief implementation of the security algorithm is made as a merged technique for information security. In addition, the algorithm uses two-level security measures: one using the Musical Cryptography and the other with Musical Steganography techniques to improve the security of the information. This study vividly proves that the information that is encrypted using the above algorithm is very well secured than the other mechanisms by the two level security systems. Therefore, these increase the security of the message and the proposed scheme is used for safe data communication. Further, this paper focuses on the strength of combining security techniques to secure the communication over an open channel by encrypting bit formatted of any form of message before its transmission.
Paddy husk pyrolysis in a small scale down draft double chamber (DDDC) pyrolyser: heat of pyrolysis
(University of Peradeniya, Sri Lanka, 2019-09-12) Alahakoon, A. M. Y. W.; Nilmalgoda, E. P. R. H. H. W.; Karunarathna, A. K.; Dharmakeerthi, R. S.
Conversion of biomass wastes into energy rich resources by thermochemical treatment methods like pyrolysis has been identified as one of the most sustainable solution for energy and resource recovery. Understanding the thermal behavior of these thermochemical processes is very important in developing energy efficient pyrolysis technologies. The heat of pyrolysis can be described as the energy released or absorbed during the chemical conversion of biomass into pyrolysis products. In the absence of micro-scale thermogravimetric analysis, the stoichiometric method with the use of macromolecular conversions can alternatively be used in finding the heat of pyrolysis. In this research, an overall stoichiometric equation was developed for producing biochar from the pyrolysis of rice husk. The stoichiometric equation was developed using experimental and literature data while the heat of pyrolysis was calculated by the difference of total Higher Heating Values (HHV) (kJ/mol) of pyrolysis products and biomass inputs. Subsequently, heat of pyrolysis for paddy husk in a small scale down draft double chamber (DDDC) pyrolyser unit was estimated. The mean compositional formulas for paddy husk and biochar were found with the help of elemental analysis in literature and the syngas composition was estimated experimentally using a Gasboard 3100P syngas analyzer. The remaining mass was estimated as the tar fraction derived during the thermal decomposition. The developed stoichiometric equation for reaction of 1mol (CH₁.₅₅₆O₀.₆₁₇) of paddy husk yields biochar (CH₀.₂₆O₀.₁₃₄), H₂, CO, CH₄, C₂H₄, CO₂, H₂O and tar (CH₀.₈₀₁O₀.₃₇₅) in the molar ratios of 0.516, 0.017, 0.051, 0.009, 0.0004, 0.033, 0.285, 0.389, respectively. Calculated heat of pyrolysis was +31.64 kJ/molfeed at an average pyrolysis temperature of 823 K. This positive energy value indicated that the pyrolysis of paddy husk in the used DDDC reactor was an endothermic reaction requiring an external energy supply to initiate and continue the pyrolysis process.
Design and development of a prototype extruder for manufacturing of recycled plastic composites
(University of Peradeniya, Sri Lanka, 2019-09-12) Ranasinghe, T.; Piyathilake, U.; Karunarathna, A.; Ariyawansha, R. T. K.; Gunasekara, C.; Basnayake, B. F. A.
The use of plastic wastes to develop construction materials such as bricks, interlocks, railway sleepers, paving slabs, and fence columns is a new concept in Sri Lanka as the technology to develop such materials is still not readily available in the country. Thus, there is a need for development of technology to use waste plastic as a strategy of waste management and also to use waste as an alternative construction material through an appropriate recycling process. This study was aimed at designing and developing a prototype extruder for manufacturing of plastic-based composite samples through hot extrursion of waste plastics and re-molding with bulking agents such as sand, sawdust, and metal aggregates. A prototype extruder was designed and fabricated. The major components of the machine include infrared heating elements with price temperature control circuit, melting and mixing chamber manufactured by steel cylinders, screw piston and extruding nozzle fixed at the end of heating chamber. The extruder was designed to heat and melt shredded plastic waste at 180 °C and then to mix with different bulking agents such as dry sand, dried sawdust and chips stones at different ratios. After 15-20 minutes of heating and mixing, depending on bulking materials, the hot blended composite was discharged into the mold by a screw threaded piston. The molded specimen was cooled to remove from the mold. Throughput of the extruder was 1.2 kg/hr on an average and functional efficiency was 80%. The developed technology can easily be scaled up for commercial production of building materials, having compressive strengths of 3-18.5 MPa at fracture. Even a small scale entrepreneur would be able to produce waste polypropylene or polyethylene-based composites material to replace existing building materials like bricks, tiles, paving blocks, and drainage pipes. Further studies are needed to mechanize the mixing, molding processes and pollution controls of dioxins and furans.
Modelling and simulation of natural ventilation provision of a computer lab for energy management analysis and applications
(University of Peradeniya, Sri Lanka, 2019-09-12) Pallegedara, A.; Kumar, S. A. V.
The Proposed research, we investigate the air flow distribution in the computer laboratory room which is under the tropical natural ventilation circumstances. The investigation has been directed to develop a 3D Computational Fluid Dynamics model for the computer room. Rendering and computational calculations are handled by finite element methods for modeling and simulation of the proposed analysis. Physics of Turbulent Flow combined with k-ε model and commercial version of COMSOL Multi-physics® were used for the simulation. While laminar flow pattern was considered and used for the primary simulation, simulation has been given to be converged in objects under steady state conditions. Open windows and doors in different orientations were taken as inlets and outlets for studying the behavior of natural ventilation system. The inlet velocity is provided to be in between 2 m/s – 3m/s, varying with time were simulated. The velocity distribution of air was obtained by solving the continuity and momentum equations of transport phenomena. Investigation carried out under Sri Lankan environmental parameters. However, the simulation has not been given an acceptable convergent when the inlet velocity is increased beyond 3 m/s, for turbulent k-ε flow model. Results are verified with the literature given for experimental results under similar orientation of objects and ventilation setups with 97 % confidence, including 12 personal computers with six 1200 KVA UPS and 15 human sources of heating at constant rate. This primary study is expected to be used in energy audits and management analysis in the directions of green-building setups towards utilizing natural ventilations in universities by reducing the number of Air-conditioner units in new buildings and also which are currently being under operation. Turbulent air flow and heating will be studied under different and extended fluid dynamics model as next step of the extended research.
A multispectral imaging system for industrial applications
(University of Peradeniya, Sri Lanka, 2019-09-12) Prabhath, G. W. K.; Bandara, W. G. C.; Dissanayake, D. W. S. C. B.; Herath, H. M. V. R.; Godaliyadda, G. M. R. I.; Ekanayake, M. P. B.; Fernando, M. A. R. M.
Multi-spectral imaging (MSI) is a technique for obtaining spectral information of an object. MSI has rapidly evolved as a non-destructive and non-invasive analytical method in many industrial applications. Multispectral images are rich in information compared to the standard RGB images because they have the capability of acquiring spectral information beyond the RGB bands. Therefore, multispectral images can be used to classify object properties more accurately than an RGB image. However, commercially available multi-spectral cameras with high spectral resolution are very expensive and the implementation of such imaging system is not affordable for medium scale enterprises. In the first part of this research, we were designed an MSI system that can be customized for use in many industrial applications. The developed MSI system can capture multispectral images from near ultraviolet (N-UV) to near infrared (NIR) region of the electromagnetic spectrum with a spectral resolution of nine spectral bands (405 nm - 960 nm). The light emitted by the light emitting diodes reaches the object which is placed inside a dark chamber through an integrating hemisphere. The multi-spectral images of the object were captured using a monochrome camera with a resolution of 1.3M Pixels and saved for each flash. In the second part of this research, MSI system was used to estimate the leakage current through algae aided insulators used in high voltage (HV) transmission lines. The leakage current flows in HV transmission lines are mainly due to the algae contaminated insulators. Inspection of HV insulator conditions are done as visual inspection tasks. However, this process is expensive, time consuming and required skilled workers. The results show that use of MSI system for the condition assessment of HV insulators remotely. Additionally, a hybrid machine learning algorithm was developed based on principal component analysis (PCA) and multivariate statistical methods to estimate the leakage currents through algae aided ceramic plates.
Production of aqueous biochar biocatalyst for agricultural sustainability
(University of Peradeniya, Sri Lanka, 2019-09-12) Wasana, W. L. N.; Ariyawansha, R. T. K.; Basnayake, B. F. A.
Addition of biochar during composting will reduce the loss of nitrogen and produce nutrient stabilized organic fertilizer. Better results can be obtained by using biologically activated/catalyzed biochar. Therefore, a study was conducted to produce and add activated biochar during the active phase of composting process. To produce an aqueous biocatalyst, slurry was prepared by mixing shredded Gliricidia sepium leaves(1 kg), water (3 L) and Eppalawa rock phosphate (8 g). The biocatalyst was prepared under aerobic conditions in an aerobic reactor which was fabricated using a 25 L plastic container, Perspex pipes, and an aerator. 1.5 kg of biochar produced from Gliricidia sepium wood in a pyrolyzer was added to the slurry intermittently until it reaches neutral pH. It took 24 days to reach a neutral pH value. The highest available nitrogen of 243 mg/L, total potassium of 8,125 mg/L and total phosphorus of 53.4 mg/L was obtained on 15ᵗʰ day at the pH 6. Through a repeated experiment, it was found that biocatalyst can be produced within 5 days. Two compost piles were prepared using fresh immature Panicum maximum grass (18 kg) and Gliricidia sepium leaves (2 kg)/ pile. Cultured biochar biocatalyst was mixed with 6% dry weight basis to one pile and raw biochar (6%) was incorporated to the other pile. N, P, K levels of all compost piles after 8 weeks were within the recommended levels. The highest nitrogen of 20.3 g/kg, and potassium of 83.71 g/kg remained in 6% biocatalyst compost. Phosphorus content of 6% biocatalyst compost was 0.67 g/kg of dry compost and it was 0.72 g/kg in 6% biochar compost. The pH value of produced compost with biochar biocatalyst was 8.8 and it was 9.2 in compost with 6% biochar. The made compost is very suitable and perhaps cost-effective for acidic soils to improve soil nutrient status unlike the addition of lime.
Deep learning based automatic tuberculosis screening system
(University of Peradeniya, Sri Lanka, 2019-09-12) Dasanayaka, C.; Dissanayake, M. B.
Given that, Tuberculosis (TB) is completely curable when diagnosed at an early stage, TB screening plays an important role in preventive care. According to the World Health Organization TB is on the rise worldwide, and the largest cause behind this increase is inadequate control in developing nations. Even though several laboratory based testing methods are available for the diagnosis of TB, they are time consuming, expensive and very limited in rural areas. As a solution to this problem, we present an accurate automated TB screening system using frontal chest X-rays, which can be utilized with negligible human interaction. The two datasets of chest radiography that were used in this research are available in US National Library of Medicine, and they were acquired from the Department of Health and Human Service, Montgomery Country, Maryland, USA, and Shenzhen No 3 Peoples Hospital in China. Our proposed method consists of two sub models, namely: lung segmentation and classification sub-systems. In order to exclude the area that are not pertinent to lungs, we used UNET convolutional neural network (CNN) for segmentation model and for feature extraction and classification we have used ensemble of two deep convolutional neural networks (DCNN), VGG16 and InceptionV3. By using image preprocessing techniques such as contrast limited adaptive histogram equalization (CLAHE), median filtering based noise removal with heavy data augmentation, hyper-parameter tuning, and model ensembling, we were able to achieve classification accuracy of 95% with Youden’s index of 0.906, sensitivity of 97.1% and specificity of 93.5%, which is a considerable improvement compared to the existing work in the literature. The tedious task of hyper parameter tuning was done by using a genetic algorithm. Due to the hyper-parameter tuning to match the task in hand, we were able to reduce the potential of over-fitting. Overall, the model presented could be quite helpful for the countries with low human experts in this field of medicine. Furthermore, since the solution presented is inexpensive, easily accessible, highly accurate, and can be used to screen a large population instantly, it can be adopted in low income countries.
Interference of elevated serum bilirubin in serum creatinine estimation by Jaffe method and enzymatic method
(University of Peradeniya, Sri Lanka, 2019-09-12) Wickramarathne, W. R. S.; Dharmapala, A.; Dissanayaka, A. M. S. D. M.
Diseases related to the liver and kidney are encountered widely. Especially kidney disease is a major health problem in Sri Lanka. Furthermore, many studies have been conducted to determine the interfering substances on Jaffe method and enzymatic method in determining the serum creatinine level. Serum bilirubin has been explored as an interfering substance. However, the results have been inconclusive. The study aimed to determine whether there is an association between elevated serum bilirubin levels and creatinine levels, or whether serum bilirubin contributes to an error which affects the laboratory techniques. This analytical and cross-sectional study was conducted among 49 patients with elevated serum bilirubin levels at teaching hospitals Peradeniya and Kandy. A venous blood sample was obtained from the patients. Measurement of serum bilirubin and creatinine levels before and after photolysis were performed by Indiko clinical chemistry analyzer. Photolysis procedure was performed to reduce the high serum bilirubin levels to more physiological levels. The Wilcoxon Signed Rank Test indicated that the median post-photolysis test ranks were statistically significantly higher than the median pre-photolysis test ranks by the Jaffe method (Z= 5.959, P < 0.005). Moreover, the median post-photolysis test ranks were statistically significantly higher than the median pre-photolysis test ranks by the enzymatic method (Z= 5.595, P < 0.005). The correlation coefficient (r) for bilirubin concentration and creatinine concentration by Jaffe method before photolysis was -0.398, p= 0.005. The r for bilirubin concentration and creatinine concentration by enzymatic method before photolysis was -0.342, P= 0.016. Both correlations were statistically significant negative correlations. In present study elevated serum bilirubin levels had statistically significant interferences on both Jaffe and enzymatic method. By considering the mean differences, mean difference by Jaffe method was higher than enzymatic method. Therefore, it is recommended that enzymatic method may be used in measuring serum creatinine in patients with hyperbilirubinemia.
Photodegradation of rhodamine B over magnetically separable Fe3O4-TiO2 photocatalyst
(University of Peradeniya, Sri Lanka, 2019-09-12) Edirisinghe, D. I. U.; Jayaweera, P. M.; Palliyaguru, L.
Titanium dioxide (TiO₂) is one of the most widely used materials in water purification. One of the largest disadvantages of using TiO₂ in water purification is the high cost and the secondary pollution associated with the catalyst regeneration process. Therefore, use of magnetic titania is highly effective as a catalyst material as it can be carried out via magnetic separation. Results of this investigation show that magnetic titania, Fe₃O₄⁻TiO₂ can be directly prepared from the HCl leachate of ilmenite. Further, the as-prepared composite was modified to increase TiO₂ percentage by removing a fraction of iron in the leachate using the anionic resin IRA-410Cl. According to the XRD analysis, the crystal planes (310) and (430) corresponding to the 2θ values of 32.62⁰ and 53.01⁰ respectively, were resulted from Fe₃O₄⁻ Further, for TiO₂, an XRD peak with the crystal plane (101) corresponds for the 2θ value of 23.21⁰ was also obtained. In the FTIR spectrum, the presence of peaks at 527 cm⁻¹ for Fe-O-Fe and at 1404 cm⁻¹ for Ti-O-Ti vibrational modes also confirm the chemical identity of the Fe₃O₄⁻TiO₂ composite. The mass susceptibility value of -4.3x10⁻³ indicates that it is sufficiently large for the recovery process via magnetic separation. Photodegradation efficiencies of Rhodamine B were tested using as- prepared magnetic titania & Degussa P25. Fe₃O₄⁻TiO2 composite bleached the colour by 50% in 25 min, whereas Degussa P25 needed only 18 min. Therefore, Fe₃O₄⁻TiO₂ may be having a good potential for the application in water purification.
Household practice and factors influencing the administration & storage of reconstituted medicinal syrups among parents of paediatric patients presenting to the pharmacy of the out patients department, teaching hospital, Jaffna
(University of Peradeniya, Sri Lanka, 2019-09-12) Abiramy, K.; Thuvaragan, S.; Sathiadas, M. G.; Surenthirakumaran, R.
Most of the paediatric oral medications are prepared as dry powders for oral suspension. The correct administration and storage of reconstituted medicinal syrups is crucial towards ensuring safety and achieving therapeutic goals in paediatric patients. The purpose of this study was to describe the household practice and influencing factors on the administration and storage of reconstituted medicinal syrups among parents of paediatric patients at the OPD pharmacy. This study was descriptive cross-sectional design. It was carried out with 422 parents of paediatric patients under the age of 12 years with a response rate of 98.8%. Participants were selected systematically, and an interviewer administered validated questionnaire was used to collect data from parents. The data were entered into SPSS version 23 and descriptive and bivariate analysis was carried out. The majority (71.5%, n=298) of the study population had satisfactory household practice on the administration and storage of reconstituted medicinal syrups. Further analysis using chi square test for the associated socio demographic factors showed statistically significant association between the type of practice and monthly income of population. Also, statistically significant difference was observed between practice and sources of information and also between practice and ability to read and understand the medication label instruction clearly. In conclusion, satisfactory practice among parents of paediatric patients on the administration and storage of reconstituted medicinal syrups was observed. Further improvement can be done if health care professionals including physicians and pharmacists pay more attention to improve parents’ practice on administration and storage of reconstituted medicinal syrups.
An automated algorithm to quantify cardiothoracic ratio (CTR) in tele chest X-rays
(University of Peradeniya,Sri Lanka, 2019-09-12) Sinthuja, S.; Perera, U. L. V. M.; Tinusanth, K.; Nawarathna, R. D.; Kulatunga, S.
In radiography, analysis of tele chest radiographs and measurement of the Cardio Thoracic Ratio (CTR) help to evaluate cardiac enlargement. Usually, CTR values are measured manually using either normal rulers or digitized rulers which are vulnerable to technical errors. Hence, our aim of this research is to introduce an automated algorithm to measure CTR using digital image processing techniques. First, the automated algorithm preprocesses the X-Ray image using histogram equalization and median filtering. Second, the image is segmented with an advanced region-growing algorithm using two seed points in the lungs and the segmented image is fine-tuned using shrink and reconstruct morphological operations to extract the area of the heart and lungs. Finally, the transverse diameter of the thorax and the widest length of the heart are calculated from the segmented binary image for the CTR calculation. 200 digital tele chest radiographs were obtained from patients who are between the age of 18 and 65. For each radiograph, the CTR value was calculated using both the automated algorithm and the manual method using digital rulers. Manually calculated CTR was assessed by a radiologist. Two CTR values were compared statistically. For that, the heart area of each X-Ray image was assessed as normal or abnormal and compared against the radiologist’s assessment of the same. An accuracy rate of 83.5% was achieved for the diagnosis of the abnormal size of the heart. Higher accuracy was reported for calculation of the transverse diameter of the thorax compared to the calculation of the widest length of the heart. One limitation of the algorithm is the inconsistency in the segmentation of the lower heart border due to the soft tissues in the lower part of the heart and lung pathology. Overall the results show that the proposed image processing based CTR calculation algorithm could be effectively applied for the diagnosis of the enlargement of the heart.
Recent developments in extrusion of bio-based thermoplastic material
(University of Peradeniya, Sri Lanka, 2019-09-12) Fernando, N. M. L.; Manamperi, W. A.; Manipura, W. M. J. A. S. B.; Gunathilake, C. A.
Adverse effects of petroleum based synthetic polymers on the economy and the environment have led to the growth of renewable bio-based polymer market. The use of starch-, protein- and cellulose-based polymers are increasing due to their biodegradability, sustainability and lesser carbon foot print. Various conventional processing techniques such as extrusion, compression molding, and casting have been modified for the processing of bio-based polymers. This review paper is intended to outline the recent developments in extrusion of bio-based thermoplastic material. Commercially, extrusion is the most widely used method for manufacturing thermoplastics. The extrusion processing conditions have a significant impact on the structure of the polymer, which in turn affect the mechanical and physical properties of the resulting plastics. Extrusion process variables such as screw speed, barrel temperature profile, feed rate, die size and shape, barrel pressure, residence time, and specific mechanical energy (SME) have been studied extensively to process bio-based material. Reactive Extrusion method which involves concurrent reaction and extrusion, is more appropriate for plasticization due to its advantages such as high conversion efficiency and a rapid rate of production. Self-wiping, co rotating twin-screw extruders are more suitable for production of bio-plastics due to more efficient mixing. Bio-based plastics are produced using various polymer blends to overcome the individual drawbacks associated with biopolymers.
Impact of climate change on dairy industry in Kurunegala district (a case study)
(University of Peradeniya, 2019-09-12) Weerasooriya, W. G. K.; Rathnayake, B. S. A. K.
Agricultural systems are increasingly being affected by adverse impacts of climate change. Impacts of Climate Change directly cause low dairy milk production. Accurate perception and adaptations of rainfall and temperature changes are inevitable challenges to dairy industry. A case study was carried out in Kuliyapitiya West and Bingiriya Divisional Secretariat Divisions (DSD) in Kurunegala district to find out the trends of rainfall and temperature changes. Also the perceptions and level of adaptation of climate smart technologies used by the dairy farmers in the selected area were investigated. Kuliyapitiya West and Bingiriya DSDs coming under Low country Intermediate Zone was purposively selected and 60 dairy farmers were selected using stratified random sampling for the survey. Meteorological data for 34 years for Kurunegala District was used for the analyses. Results showed that there is a significant (p<0.05) increasing trend in minimum mean annual temperature. A slight increasing trend in maximum mean annual temperature and the consecutive dry days were observed. A slight increasing trend in maximum mean annual temperature and the consecutive dry days were also observed. Dairy farmers’ perception about daytime and night time temperature and distribution of rainfall were different with actual changes. There was a significant relationship (p<0.05) between overall knowledge on climate smart technologies and dairy farm productivity. There was also a significant relationship (p<0.05) between the highly important climate smart adaptation practices and dairy farm productivity. It is important to developing strategies to communicate the actual changes and trends in climate to increase the awareness and change attitudes of farmers on the importance of adapting climate smart dairy technologies.
Climate and varietal choice in rice systems: evidence from path model estimation
(University of Peradeniya, 2019-09-12) Prasada, D. V. P.
Rice is the primary staple crop in South Asia. With increasing climatic volatility, exclusively rain-fed rice paddies have experienced a triple threat in droughts, floods and salinity. This study investigates the linkages of these abiotic stresses on yield and subsequent farmer decisions on varietal choice. A structural path model is estimated using 2523 farm household observations from Bangladesh farmers to obtain parameter estimates for direct effects and mediated effects discussed above. It was found that drought and flood impacts, in contrast to salinity impacts, are influential to both yield and varietal choice. The adaptation motive, however, is clear only in the case of salinity. Time preference of farmers and previous exposure to climate shocks predict adaptation motive substantively. The models reveal the following relationships among the variables of interest. Drought and flood damage has a statistically significant negative impact on yield. Salinity damage has a negative effect but not statistically significant. Among the socio-demographic variables, in all the three impact models with adaptation pathway, education level has a positive relationship with the yield. Farmers’ time preference (preference for shorter time horizons) and level of yield have negative associations with the adaptation motive. The years of experience of droughts and floods within last 5 years also have negative association to the adaptation motive. For salinity, however, the effect of previous exposure contributes positively to adaptation.
Monitoring of carbon dioxide concentration in closed environments
(University of Peradeniya, 2019-09-12) Rajapakse, R. P. N. R.; Bandaranayake, P. W. S. K.
People in the modern society spend most of their time in closed environments due to present day activities and lifestyles. Hence, the air inside closed environments plays an important role for maintaining healthy mental and physical conditions. The indoor air quality index is defined using the concentration of nitrogen dioxide, carbon monoxide, sulfur dioxide, ozone and particulate matter. But the concentration of carbon dioxide is not classified under that air quality index. However, it has been medically proven that the high concentration of carbon dioxide in closed environments affects the human health. The importance of monitoring of carbon dioxide level in closed environments has not yet been established. There are neither regulations nor standard limits set for the indoor concentration of carbon dioxide in Sri Lanka. The American Society of Heating, Refrigerating and Air-Conditioning Engineers, has set a standard carbon dioxide concentration for indoor environments as 700 ppm. In the present study, we have constructed an electronic device to simultaneously measure the carbon dioxide concentration, ambient temperature and the relative humidity. The research project was carried out to measure the concentration of carbon dioxide inside passenger vehicles, laboratories and hospital rooms with air-conditioning. The increase in carbon dioxide concentration inside those closed environments are mainly due to human respiration metabolism. Although air conditioners control the temperature and the relative humidity, it does not affect the concentration of carbon dioxide. The results show that the carbon dioxide concentration in places under investigation exceeded the limit of 700 ppm. Inside the tested vehicles, the concentration of carbon dioxide increased up to 5000 ppm creating an uncomfortable feeling for passengers. Consequently, the increase of carbon dioxide creates an unhealthy environment. Therefore, it can be concluded that the monitoring and controlling of the carbon dioxide concentration inside closed environments are important for human health.

Browse

Recent Submissions