170 results on '"Hewawasam P"'
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2. Interplay of the Indian summer monsoon and intermonsoon precipitation in Sri Lanka due to ITCZ migration during the last 80000 years
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P. N. Ranasinghe, K. A. Hughen, T. U. T. Wijewardhana, J. D. Ortiz, A. K. I. U. Kapuge, Kalpani M. Ratnayake, N. U. Nanayakkara, A. L. T. Hewawasam, Y. P. S. Siriwardana, and S. Kodithuwakku
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Medicine ,Science - Abstract
Abstract Precipitation variations in the tropical Indian Ocean region result from changes in the Indian Summer Monsoon (ISM), as well as convective and cyclonic rainfall. The relative roles of such forcing can be elucidated by constructing robust paleoclimate records, which help to better predict future variability in precipitation due to rising greenhouse gases. This study was carried out using a suite of paleoclimate proxies on a combination of marine and terrestrial sediment cores from Sri Lanka. The sites receive differing amounts of precipitation from the ISM versus convective and cyclone-driven intermonsoon rainfall and allow differentiation of precipitation sources through time. The constructed 80000-year-long precipitation record for the ISM-dominant regions of Sri Lanka shows strong sensitivity to orbital scale insolation variations as well as to millennial-scale events in the North Atlantic region. This precipitation response to external and internal forcings is a result of the combined effects of ISM and Intermonsoon intensity either of which dominated periodically. The strong positive correlation between different periods in the precipitation record and different monthly insolation curves shows that changes in solar insolation due to precession decide the dominant rainfall mechanism in the region, suggesting the ISM dominated after 13 ka (MIS1) while the first intermonsoon dominated between 29 and 13 ka (MIS2) and the second intermonsoon dominated period between 77 and 40 ka.
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- 2024
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3. Interplay of the Indian summer monsoon and intermonsoon precipitation in Sri Lanka due to ITCZ migration during the last 80000 years
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Ranasinghe, P. N., Hughen, K. A., Wijewardhana, T. U. T., Ortiz, J. D., Kapuge, A. K. I. U., Ratnayake, Kalpani M., Nanayakkara, N. U., Hewawasam, A. L. T., Siriwardana, Y. P. S., and Kodithuwakku, S.
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- 2024
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4. A review of recent advances in fungal mycelium based composites
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Madusanka, Chathura, Udayanga, Dhanushka, Nilmini, Renuka, Rajapaksha, Suranga, Hewawasam, Choolaka, Manamgoda, Dimuthu, and Vasco-Correa, Juliana
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- 2024
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5. A review of recent advances in fungal mycelium based composites
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Chathura Madusanka, Dhanushka Udayanga, Renuka Nilmini, Suranga Rajapaksha, Choolaka Hewawasam, Dimuthu Manamgoda, and Juliana Vasco-Correa
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Fungal bioresources ,Genetic modification ,Material driven design ,Mycelium based composites ,Waste management ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Abstract The increasing global population and rapid urbanization have led to high consumer demand for construction and other raw materials. Manufacturing of synthetic material usually generate a large amount of waste, resulting in significant environmental impact. Fungi are one of the key biological resources that can be used to develop a wide range of sustainable products including biodegradable materials with promising applications, with zero waste generation during the production process. Mycelium, the vegetative part of a fungus can be shaped either into pure mycelium materials or composites. Mycelium can grow its network in lignocellulosic material, combining separate pieces into a solid material which results in Mycelium-Based Composites (MBCs). The attributes of MBCs are influenced by the fungal species, the growth substrate, and the processing conditions. Both pure mycelium materials and MBCs have remarkable advantages as versatile materials because they are porous, elastic, low-density, low-cost and eco-friendly materials with potential applications in various industries. In this review, we provide an overview of the latest developments MBCs considering the possibility of using mycelium for the material-driven design (MDD) approach, and the potential of genetic and biochemical modifications to enhance mycelium properties. We therefore encourage researchers in material science and fungal biotechnology to strengthen their collaborative efforts and address the current challenges in this innovative field.
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- 2024
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6. The Impact of Software Testing on Serverless Applications
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Dilshan De Silva and Lakindu Hewawasam
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End-to-end testing ,influential factors ,integration testing ,serverless applications ,serverless testing ,shift-left approach ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
With the increasing prevalence of serverless applications, a conspicuous gap in research has emerged regarding the comprehensive insights into the ramifications of serverless technology on software testing. This study aims to bridge this gap by examining the intricate interplay between software testing and serverless applications. Its overarching objectives include identifying the multifaceted challenges and constraints encountered in testing serverless applications and formulating a cogent testing strategy. This strategy delineates the optimal balance between unit, integration, and end-to-end tests in the context of serverless applications. To achieve these objectives, the research utilizes a multifaceted approach, including interviews with seasoned industry experts who have over a decade of experience. These experts provide invaluable insights into the complex dynamics of software testing in the serverless landscape. The research findings emphasize the increased complexity in testing serverless applications and advocate for software teams to adopt a shift-left approach. This involves gaining a deep understanding of the overarching services and their constraints before developing a testing strategy. Furthermore, it is crucial to acknowledge that there is no ’one-size-fits-all’ optimal testing ratio. Instead, it is contingent upon a constellation of influential factors.
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- 2024
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7. Parenthood in people with kidney failure: evolution and evaluation of completeness of ANZDATA registry parenthood data
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Danner, Rhea, Hewawasam, Erandi, Davies, Christopher Edward, McDonald, Stephen, and Jesudason, Shilpanjali
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- 2023
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8. Patient and Partner Perspectives of Pregnancy-Related Counseling and Information Needs in Women With Kidney Disease: An Australian National Survey
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Erandi Hewawasam, Belinda Stallard, Alessandra Orsillo, Jane Boag, Charmaine Green, Laura Heffernan, Carolina Maistry, Shyamsundar Muthuramalingam, Adela Tolic, Amber Williamson, and Shilpanjali Jesudason
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counseling ,dialysis ,kidney disease ,preconception ,pregnancy ,transplant ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Introduction: The experiences and information needs for reproductive health counseling in women with chronic kidney disease (CKD) are poorly defined, despite the known importance of pregnancy planning in this higher-risk cohort. Methods: Australian adult women with CKD and their partners or family members completed a consumer codesigned survey about experiences of and preferences for pregnancy-related counseling, support, and education. Data were analyzed descriptively and with qualitative content analysis of free-text responses. Results: Responses were received from 102 women (CKD, n = 60; dialysis, n = 11; transplant, n = 26; unsure, n = 5 ) and 17 partners/family members. Pregnancy-related discussions were initiated mostly by women themselves (60.0%) compared to nephrologists (26.7%), and only after conception in 14.7%. Women found pregnancy-related discussions satisfactory (68.0%) and useful (50.7%) but also stressful (66.7%), with only 54.7% feeling in control of decision-making. Information deficits and quality, preformed decisions, clinician-patient disconnect, and burden of decision-making contributed to usefulness and outcomes of pregnancy-related counseling. Women received insufficient information about contraception (not provided in 35.2% of cases), medication safety (40.9%), fetal complications (33.8%) and emotional and psychological impact of pregnancy (73.2%). Women preferred counseling from nephrologists (86.4%), face-to-face settings (79.6%), websites (72.7%), handouts (61.4%), and online support groups (46.6%). High-quality, multiformat information by content experts, peer support, and psychological support were also strongly desired. Conclusion: This study highlights that preconception counseling and information needs of women with CKD are currently not being met. Frameworks and tools to assist patients and clinicians, particularly nephrologists, to initiate and conduct sensitive, useful, and informed shared decision-making (SDM) about pregnancy are urgently needed.
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- 2023
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9. Electrocardiographic and biochemical analysis of anthracycline induced cardiotoxicity in breast cancer patients from Southern Sri Lanka
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Sandamali, Jayasinghe Arachchige Nirosha, Hewawasam, Ruwani Punyakanthi, Fernando, Madappuli Arachchige Chaminda Sri Sampath, and Jayatilaka, Kamani Ayoma Perera Wijewardana
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- 2023
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10. Successful Management of Neutropenic Sepsis Is Key to Better Survival of Patients With Blood Cancer in Sri Lanka: Real-World Data From the Resource-Limited Setting
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Saman Hewamana, Thurairajah Skandarajah, Chathuri Jayasinghe, Samadhi Deshapriya, Dilip Gayashan, Natasha Peiris, Mahesh Harischandra, Prasanna Gunasena, Gnani Somasundaram, Vadivelu Srinivasan, Surjit Somiah, Chandana Wickramarathna, Sangeetha Hewawasam, Jayantha Balawardena, Gehan Arseculeratne, Rohini Wadanamby, Geethani Galagoda, and Bandula Wijesiriwardana
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
PURPOSESepsis is the main cause of nonrelapse mortality, and there are no published data on applicability of supportive care protocols from high-income countries such as Sri Lanka. The aim of the study was to investigate management and mortality of neutropenic episodes among Hemato-Oncology patients.MATERIALS AND METHODSRetrospective analysis of clinical characteristics, management, morbidity, and mortality of neutropenic Hemato-Oncology patients presented to the Lanka Hospital Blood Cancer Centre from January 1, 2019 to December 31, 2019 was performed.RESULTSA total of 169 neutropenic episodes were identified; 115 (68%) of such episodes were related to chemotherapy. Acute leukemia, lymphoproliferative disorders, and plasma cell disorders accounted for 23%, 69%, and 8% of patients, respectively. The median age of patients who had sepsis was 56 years, whereas that of those who had no sepsis was 53 years (P = .49). The median time to neutropenia was 9 days for those in the sepsis group compared with 8 days in the group that had no sepsis (0.64). The median neutrophil count in the group that had sepsis was 0.06, whereas it was 0.69 in the group that had no sepsis (P ≤ .05). The median time to commencement of antibiotics was 20 minutes.CONCLUSIONTo our knowledge, this is the only documented study related to outcome and successful applicability of western supportive care protocols to Sri Lankan patients with neutropenia. In this study, we have shown that neutropenic sepsis can be successfully managed in the setting of limited resources with service development, following guidelines and staff training.
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- 2024
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11. Electrocardiographic and biochemical analysis of anthracycline induced cardiotoxicity in breast cancer patients from Southern Sri Lanka
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Jayasinghe Arachchige Nirosha Sandamali, Ruwani Punyakanthi Hewawasam, Madappuli Arachchige Chaminda Sri Sampath Fernando, and Kamani Ayoma Perera Wijewardana Jayatilaka
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Anthracycline ,Breast cancer patients ,Cardiotoxicity ,Electrocardiography ,NT-proBNP ,Troponin I ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background The clinical application of anthracycline chemotherapy is hindered due to the cumulative dose-dependent cardiotoxicity followed by the oxidative stress initiated during the mechanism of action of anthracyclines. Due to a lack of prevalence data regarding anthracycline-induced cardiotoxicity in Sri Lanka, this study was conducted to determine the prevalence of cardiotoxicity among breast cancer patients in Southern Sri Lanka in terms of electrocardiographic and cardiac biomarker investigations. Methods A cross-sectional study with longitudinal follow-up was conducted among 196 cancer patients at the Teaching Hospital, Karapitiya, Sri Lanka to determine the incidence of acute and early-onset chronic cardiotoxicity. Data on electrocardiography and cardiac biomarkers were collected from each patient, one day before anthracycline (doxorubicin and epirubicin) chemotherapy, one day after the first dose, one day and six months after the last dose of anthracycline chemotherapy. Results Prevalence of sub-clinical anthracycline-induced cardiotoxicity six months after the completion of anthracycline chemotherapy was significantly higher (p 350 mg/m2 was the most significant risk factor associated with the sub-clinical cardiotoxicity in breast cancer patients under study. Conclusion Since these results confirmed the unavoidable cardiotoxic changes following anthracycline chemotherapy, it is recommended to carry out long-term follow-ups in all patients who were treated with anthracycline therapy to increase their quality of life as cancer survivors.
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- 2023
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12. Engineering Hybrid-Hydrogels Comprised of Healthy or Diseased Decellularized Extracellular Matrix to Study Pulmonary Fibrosis
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Saleh, Kamiel S., Hewawasam, Rukshika, Šerbedžija, Predrag, Blomberg, Rachel, Noreldeen, Saif E., Edelman, Benjamin, Smith, Bradford J., Riches, David W. H., and Magin, Chelsea M.
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- 2022
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13. An unusual case of a traumatic splenic rupture masquerading as myocardial ischemia: a case report
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B. M. Munasinghe, U. P. M. Fernando, Thileep Kumar, Chamika Huruggamuwa, K. A. R. L. Kuruppu, and G. G. C. Hewawasam
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Splenic injury ,Traumatic splenic rupture ,Life-threatening haemorrhage ,Case report ,Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Abstract
Abstract Background The spleen is one of the most frequently injured abdominal organs during trauma, which can result in intraperitoneal bleeding of life-threatening magnitude. Although splenic injury secondary to trivial trauma comprises a minor fraction of abdominal injuries, undiagnosed or delayed diagnosis may result in a complicated clinical course. Case presentation One such event is presented here, wherein a late diagnosis of an advanced grade splenic injury following a trivial trauma initially presented in disguise as acute myocardial ischaemia in a previously healthy South Asian woman in her late 30s. Emergency laparotomy and splenectomy were performed with simultaneous massive transfusion for a 3.5-L blood loss. She subsequently had an uncomplicated clinical course with regular surgical follow-up. Conclusion Splenic injuries might present with ambiguous symptoms such as atypical chest pain and shoulder pain, necessitating attending clinicians to have a high degree of suspicion, especially in busy units such as the emergency department (ED).
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- 2022
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14. Effectiveness of natural coagulants in water and wastewater treatment
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S. Nimesha, C. Hewawasam, D. Jayasanka, Y. Murakami, N. Araki, and N. Maharjan
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coagulants ,plant-based coagulants ,coagulation mechanism ,efficiency ,commercialization ,Environmental sciences ,GE1-350 - Abstract
Natural waterways are contaminated due to industrialization, urbanization, population growth etc., degrading their quality. Contaminated waterways cause numerous health and environmental hazards. Therefore, it is imperative to remove contaminants. Coagulation is one of the efficient primary chemical treatment methods that could be used to treat such contaminants. Natural coagulants have gained popularity in the water and wastewater treatment industry due to their advantage over chemical coagulants. Natural coagulants are derived from either plants, animals, or microorganisms. This study has elaborated on the nature and mechanisms, and types of natural coagulants. In this review work, many studies have proposed several types of natural coagulants. However, plant-based natural coagulants extracted from different plant components have been extensively discussed and compared based on their application and efficiency in water and waste treatment. The primary purpose of this review is to refine the knowledge on the potential use and optimization of the effectiveness of eco-friendly and sustainable natural coagulants. Besides, the development efforts and the barriers reported by recent findings for the commercialization of natural coagulants are also discussed. Further, few modified natural coagulants have also been presented for exploring the other possible approaches to promote their usage in water and wastewater treatment in the future studies.
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- 2022
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15. MicroRNA-9-1 Attenuates Influenza A Virus Replication via Targeting Tankyrase 1
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Gayan Bamunuarachchi, Kishore Vaddadi, Xiaoyun Yang, Quanjin Dang, Zhengyu Zhu, Sankha Hewawasam, Chaoqun Huang, Yurong Liang, Yujie Guo, and Lin Liu
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Medicine ,Internal medicine ,RC31-1245 - Abstract
An unstable influenza genome leads to the virus resistance to antiviral drugs that target viral proteins. Thus, identification of host factors essential for virus replication may pave the way to develop novel antiviral therapies. In this study, we investigated the roles of the poly(ADP-ribose) polymerase enzyme, tankyrase1 (TNKS1) and the endogenous small noncoding RNA, miR-9-1 in influenza A virus (IAV) infection. Increased expression of TNKS1 was observed in IAV-infected human lung epithelial cells and mouse lungs. TNKS1 knock-down by RNA interference repressed influenza viral replication. A screen using TNKS1 3’-untranslation region (3’-UTR) reporter assays and predicted microRNAs identified that miR-9-1 targeted TNKS1. Overexpression of miR-9-1 reduced influenza viral replication in lung epithelial cells as measured by viral mRNA and protein levels as well as virus production. miR-9-1 induced type I interferon production and enhanced the phosphorylation of STAT1 in cell culture. The ectopic expression of miR-9-1 in the lungs of mice by using an adenoviral viral vector enhanced type I interferon response, inhibited viral replication and reduced susceptibility to IAV infection. Our results indicate that miR-9-1 is an antiinfluenza microRNA that targeting TNKS1 and enhanced cellular antiviral state.
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- 2023
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16. Comparison of catheters or new arteriovenous fistulas for commencement of haemodialysis in pregnant women with chronic kidney disease: an international observational study
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Jesudason, Shilpanjali, Hewawasam, Erandi, Moloney, Brona, Tan, Rachel, Li, Joule, Blakey, Hannah, Bramham, Kate, Hall, Matthew, Juneja, Rajiv, Jarvis, Elizabeth, Lightstone, Liz, Lipkin, Graham, and Hladunewich, Michelle A.
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- 2022
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17. Adaptation of the revised universal soil loss equation to map spatial distribution of soil erosion in tropical watersheds: a GIS/RS-based study of the Upper Mahaweli River Catchment of Sri Lanka
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Somasiri, I. S., Hewawasam, Tilak, and Rambukkange, M. P.
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- 2022
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18. The accuracy of fatty liver index for the screening of overweight and obese children for non-alcoholic fatty liver disease in resource limited settings
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Mawanane Hewa Aruna Devapriya de Silva, Ruwani Punyakanthi Hewawasam, Chanika Roshini Kulatunge, and Rathnayake Mudiyanselage Anjali Chamika
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Childhood obesity ,NAFLD ,Screening ,Fatty liver index ,Ultrasonography ,Resource limited settings ,Pediatrics ,RJ1-570 - Abstract
Abstract Background Non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease among children with a higher prevalence among obese. Fatty liver index (FLI), an algorithm derived to screen NAFLD using the waist circumference, body mass index, triglyceride and gamma glutamyl-transferase concentration was rarely investigated in Asian paediatric population. Since each component is routinely measured in clinical practice, it is feasible to measure FLI even in resource limited settings. Hence, we determined the accuracy of FLI for the screening of NAFLD in obese children in Southern Sri Lanka. Methods A descriptive cross sectional study was conducted on ninety five children (56 boys) aged 5–15 years with BMI ≥ 85th percentile for age and gender based on CDC 2000 growth charts recruited from the nutrition clinic at the Teaching Hospital, Karapitiya, Sri Lanka. NAFLD was diagnosed by ultrasonography. Factors associated with ultrasonographic fatty liver such as biochemical parameters and fatty liver index in either sex or the whole population were determined by a multivariate analysis. The ability of FLI to screen NAFLD was determined by the analysis of area under the receiver operator characteristic curve (AUROC) and the maximum Youden index analysis. Results Overweight and obese children with ultrasonographic fatty liver had a significantly higher FLI than those without fatty liver according to the multivariate analysis performed (Odds ratio 3.524; 95% CI 1.104–11.256, P = 0.033). AUROC of FLI for NAFLD was 0.692 (95% CI; 0.565–0.786) and the optimal cut off value for the screening of NAFLD was 30 (Maximum Youden index 0.2782, Sensitivity, 58.33%; Specificity, 69.49%). Conclusion FLI could accurately be used in resource limited community settings and in epidemiological studies to screen overweight and obese children for NAFLD.
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- 2022
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19. An unusual case of a traumatic splenic rupture masquerading as myocardial ischemia: a case report
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Munasinghe, B. M., Fernando, U. P. M., Kumar, Thileep, Huruggamuwa, Chamika, Kuruppu, K. A. R. L., and Hewawasam, G. G. C.
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- 2022
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20. The accuracy of fatty liver index for the screening of overweight and obese children for non-alcoholic fatty liver disease in resource limited settings
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de Silva, Mawanane Hewa Aruna Devapriya, Hewawasam, Ruwani Punyakanthi, Kulatunge, Chanika Roshini, and Chamika, Rathnayake Mudiyanselage Anjali
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- 2022
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21. Past, Present and Future of Path-Planning Algorithms for Mobile Robot Navigation in Dynamic Environments
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H. S. Hewawasam, M. Yousef Ibrahim, and Gayan Kahandawa Appuhamillage
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Dynamic environment ,mobile robot ,navigation ,obstacle avoidance ,path-planning ,Electronics ,TK7800-8360 ,Industrial engineering. Management engineering ,T55.4-60.8 - Abstract
Mobile robots have been making a significant contribution to the advancement of many sectors including automation of mining, space, surveillance, military, health, agriculture and many more. Safe and efficient navigation is a fundamental requirement of mobile robots, thus, the demand for advanced algorithms rapidly increased. Mobile robot navigation encompasses the following four requirements: perception, localization, path-planning and motion control. Among those, path-planning is a vital part of a fast, secure operation. During the last couple of decades, many path-planning algorithms were developed. Despite most of the mobile robot applications being in dynamic environments, the number of algorithms capable of navigating robots in dynamic environments is limited. This paper presents a qualitative comparative study of the up-to-date mobile robot path-planning methods capable of navigating robots in dynamic environments. The paper discusses both classical and heuristic methods including artificial potential field, genetic algorithm, fuzzy logic, neural networks, artificial bee colony, particle swarm optimization, bacterial foraging optimization, ant-colony and Agoraphilic algorithm. The general advantages and disadvantages of each method are discussed. Furthermore, the commonly used state-of-the-art methods are critically analyzed based on six performance criteria: algorithm’s ability to navigate in dynamically cluttered areas, moving goal hunting ability, object tracking ability, object path prediction ability, incorporating the obstacle velocity in the decision, validation by simulation and experimentation. This investigation benefits researchers in choosing suitable path-planning methods for different applications as well as identifying gaps in this field.
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- 2022
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22. Insights into the impact of pregnancy on kidney disease
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Hewawasam, Erandi and Jesudason, Shilpanjali
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- 2023
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23. Microplastics Contamination in Commercial Green Mussels from Selected Wet Markets in Thailand
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Imasha, Hewawasam Udumullage Erangi and Babel, Sandhya
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- 2021
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24. Small and Medium-Sized Entrepreneurs’ Perceptions of Flood Loss and Damage in Sri Lanka
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Vindya Hewawasam and Kenichi Matsui
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loss and damage ,floods ,small and medium-sized entrepreneurs ,Colombo ,Sri Lanka ,Science - Abstract
As climate change has intensified flood risk and damage in many low-lying areas of the world, small and medium-sized enterprises (SMEs), which typically exist in developing countries, have endured high flood risks without much support for relief. This study investigates how SMEs in flood-prone areas of Colombo, Sri Lanka, the largest business hub in the country, have perceived and dealt with flood loss and damage in the past ten years. We conducted field surveys and a questionnaire survey among 60 SME owners in two flood-prone administrative units from March to June 2020. The results show that informal businesses experienced more flood loss and damage than other community members. Also, the community dominated by informal businesses tended to be located closer to potential flood sources. Ownership and awareness about flood insurance were very low in our study areas. Temporary business closure was the most serious loss experienced by informal business communities. These communities depended on personal savings to recover from floods. Our multiple regression analysis found that age, education, and experience significantly influenced SME owners’ perceptions and experiences about floods. After discussing these findings, this paper offers recommendations to mitigate disaster loss and damage to SMEs. In particular, it highlights the importance of community-level awareness and mitigation efforts rather than administrative unit-level mitigation plans. Also, the government needs to register informal businesses by providing a more flexible business registration mechanism.
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- 2023
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25. Cinnamomum zeylanicum Blume (Ceylon cinnamon) bark extract attenuates doxorubicin induced cardiotoxicity in Wistar rats
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Jayasinghe Arachchige Nirosha Sandamali, Ruwani Punyakanthi Hewawasam, Kamani Ayoma Perera Wijewardana Jayatilaka, and Lakmini Kumari Boralugoda Mudduwa
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Doxorubicin ,Cardiotoxicity ,Oxidative-stress ,Cinnamomum zeylanicum bark extract ,Antioxidant effect ,Myeloperoxidase ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Anti-tumour efficacy of doxorubicin is hindered by the cumulative dose-dependent cardiotoxicity induced by reactive oxygen species during its metabolism. As Cinnamomum zeylanicum has proven antioxidant potential, objective of this study was to investigate the cardioprotective activity of Cinnamomum bark extract against doxorubicin induced cardiotoxicity in Wistar rats. Physicochemical and phytochemical analysis was carried out and dose response effect and the cardioprotective activity of Cinnamomum were determined in vivo. 180 mg/kg dexrazoxane was used as the positive control. Plant extracts were free of heavy metals and toxic phytoconstituents. In vivo study carried out in Wistar rats revealed a significant increase (p
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- 2021
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26. Improving Diverse and Equitable Involvement of Patients and Caregivers in Research in CKD: Report of a Better Evidence and Translation–Chronic Kidney Disease (BEAT-CKD) Workshop
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Cazzolli, Rosanna, Sluiter, Amanda, Bateman, Samantha, Candler, Hayley, Cho, Yeoungjee, Cooper, Tess, Craig, Jonathan C., Dominello, Amanda, Duncanson, Emily, Guha, Chandana, Hawley, Carmel M., Hewawasam, Erandi, Hickey, Laura, Hill, Kathy, Howard, Kirsten, Howell, Martin, Huuskes, Brooke M., Irish, Georgina L., Jesudason, Shilpanjali, Johnson, David W., Kelly, Ayano, Leary, Diana, Manera, Karine, Mazis, Jasmin, McDonald, Stephen, McLennan, Helen, Muthuramalingam, Shyamsundar, Pummeroy, Margaret, Scholes-Robertson, Nicole, Teixeira-Pinto, Armando, Tunnicliffe, David J., van Zwieten, Anita, Viecelli, Andrea K., Wong, Germaine, and Jaure, Allison
- Abstract
Patient and caregiver involvement can enhance the uptake and impact of research, but the involvement of patients and caregivers who are underserved and marginalized is often limited. A better understanding of how to make involvement in research more broadly accessible, supportive, and inclusive for patients with chronic kidney disease (CKD) and caregivers is needed. We conducted a national workshop involving patients, caregivers, clinicians, and researchers from across Australia to identify strategies to increase the diversity of patients and caregivers involved in CKD research. Six themes were identified. Building trust and a sense of safetywas considered pivotal to establishing meaningful relationships to support knowledge exchange. Establishing community and connectednesswas expected to generate a sense of belonging to motivate involvement. Balancing stakeholder goals, expectations, and responsibilitiesinvolved demonstrating commitment and transparency by researchers. Providing adequate resources and supportincluded strategies to minimize the burden of involvement for patients and caregivers. Making research accessible and relatablewas about nurturing patient and caregiver interest by appealing to intrinsic motivators. Adapting to patient and caregiver needs and preferencesrequired tailoring the approach for individuals and the target community. Strategies and actions to support these themes may support more diverse and equitable involvement of patients and caregivers in research in CKD.
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- 2024
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27. Machine Learning-Based Agoraphilic Navigation Algorithm for Use in Dynamic Environments with a Moving Goal
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Hasitha Hewawasam, Gayan Kahandawa, and Yousef Ibrahim
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agoraphilic ,free-space ,mobile robots ,navigation ,dynamic environment ,moving goal ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
This paper presents a novel development of a new machine learning-based control system for the Agoraphilic (free-space attraction) concept of navigating robots in unknown dynamic environments with a moving goal. Furthermore, this paper presents a new methodology to generate training and testing datasets to develop a machine learning-based module to improve the performances of Agoraphilic algorithms. The new algorithm presented in this paper utilises the free-space attraction (Agoraphilic) concept to safely navigate a mobile robot in a dynamically cluttered environment with a moving goal. The algorithm uses tracking and prediction strategies to estimate the position and velocity vectors of detected moving obstacles and the goal. This predictive methodology enables the algorithm to identify and incorporate potential future growing free-space passages towards the moving goal. This is supported by the new machine learning-based controller designed specifically to efficiently account for the high uncertainties inherent in the robot’s operational environment with a moving goal at a reduced computational cost. This paper also includes comparative and experimental results to demonstrate the improvements of the algorithm after introducing the machine learning technique. The presented experiments demonstrated the success of the algorithm in navigating robots in dynamic environments with the challenge of a moving goal.
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- 2023
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28. Modulation of Rab7a-mediated growth factor receptor trafficking inhibits islet beta cell apoptosis and autophagy under conditions of metabolic stress
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Nirun V. Hewawasam, Fadel Lhaf, Henry A. Taylor, Katrina Viloria, Amazon Austin, Aileen King, Peter Jones, Lucy Jones, Mark D. Turner, and Natasha J. Hill
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Medicine ,Science - Abstract
Abstract Regenerative medicine approaches to enhancing beta cell growth and survival represent potential treatments for diabetes. It is known that growth factors such as insulin, IGF-1 and HGF support beta cell growth and survival, but in people with type 2 diabetes the destructive effects of metabolic stress predominate and beta cell death or dysfunction occurs. In this study we explore the novel hypothesis that regulation of growth factor receptor trafficking can be used to promote islet beta cell survival. Growth factor signalling is dependent on the presence of cell surface receptors. Endosomal trafficking and subsequent recycling or degradation of these receptors is controlled by the Rab GTPase family of proteins. We show that Rab7a siRNA inhibition enhances IGF-1 and HGF signalling in beta cells and increases expression of the growth factor receptors IGF-1R and c-Met. Furthermore, Rab7a inhibition promotes beta cell growth and islet survival, and protects against activation of apoptosis and autophagy pathways under conditions of metabolic stress. This study therefore demonstrates that Rab7a-mediated trafficking of growth factor receptors controls beta cell survival. Pharmaceutical Rab7a inhibition may provide a means to promote beta cell survival in the context of metabolic stress and prevent the onset of type 2 diabetes.
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- 2020
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29. Is leishmaniasis adequately notified in Sri Lanka? A survey among doctors from an endemic district, Sri Lanka
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Chandana Hewawasam, Hema S. Weerakoon, Vyshnavi Thilakan, Tishni Lelwala, Kalana Prasanka, A. S. Rathnayaka, Shanika Gamage, and Suneth Agampodi
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Leishmaniasis ,Notification ,Physicians ,Knowledge ,Attitude ,Practice ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Leishmaniasis is a notifiable disease in Sri Lanka since 2008. Previous studies show a gap in the notification of leishmaniasis. The purpose of the present study was to determine the Knowledge, attitudes and practice of medical officers regarding leishmaniasis. Methods A cross-sectional study was conducted in the Anuradhapura district which reported the highest case load of leishmaniasis. Medical officers from public and private health care institutes in the area filled a self-administered questionnaire in the presence of the investigators. Results One hundred and eighty-eight (188) medical officers completed the questionnaire. Of them, 95.7% were aware of leishmaniasis as a parasitic infection and 84.7% correctly identified Leishmania donovani as the causative organism in Sri Lanka. From the respondents, 181 (96.8%) knew that the vector of leishmaniasis is sand fly. Cutaneous leishmaniasis was reported as the most prevalent form of leishmaniasis in the country by 176 (94.1%). Nearly half of the respondents (98, 54.1%) were aware of the fact that the Anuradhapura district has the highest disease burden. Many of them had the idea that leishmaniasis is an emerging disease (155, 84.3%,) and early diagnosis is important in controlling the disease (163, 89.1%). Although about three fourth (123, 73.7%,) of the participants mentioned that leishmaniasis should be notified at first clinical suspicion, only 74 (42.5%) were aware that it is a legal requirement. Some medical officers (39, 22%) believed that the current notification system in the country is not effective. Unavailability of notification forms (60, 36.8%) heavy workload (85, 50.3%) and inadequate supportive staff (55, 35.1%) were reported as barriers for timely notification. Even though 105 (58.0%) of medical officers had suspected leishmaniasis during the last 8 years period only 35 (19.4%) had notified. Conclusions Even though more than 90% of the participants had good theoretical knowledge about leishmaniasis; notification of leishmaniasis is considerably inadequate. This study emphasizes the need for greater efforts to improve the notification of leishmaniasis in Sri Lanka.
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- 2020
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30. Waste heat recovery from thermo-electric generators (TEGs)
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L.S. Hewawasam, A.S. Jayasena, M.M.M. Afnan, R.A.C.P. Ranasinghe, and M.A. Wijewardane
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Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Thermo-electric generators (TEGs) have been identified as promising solid-state devices to recover exhaust waste in internal combustion engines (ICEs). As the TEGs are able to convert heat directly into electricity, they can be used to down size the alternator of the ICEs. However, the addition of new devices to the engine exhaust system leads to increase the back pressure of the engine and reduces the overall efficiency of the engine. Therefore, this study is conducted to understand the possibility of integrating the TEG to the muffler of the engine, without interrupting the functionality of the muffler to recover the waste heat of the engine exhaust system. Findings of the study shows that the thermo-electric modules (TEMs) can be easily integrated to the muffler and electricity can be conveniently generated using the exhaust energy available in the hot exhaust gas. Keywords: Energy recovery, Thermo-electric generators, Exhaust system, Internal combustion engines, Availability
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- 2020
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31. South Australian prospective cohort study evaluating outcomes of maternal kidney and cardiac disease in pregnancy: a protocol
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Erandi Hewawasam, Shilpanjali Jesudason, Margaret Arstall, Jarrad Hopkins, Emily Aldridge, and Prabha Andraweera
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Medicine - Published
- 2022
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32. Antiurolithiatic Potential of Three Sri Lankan Medicinal Plants by the Inhibition of Nucleation, Growth, and Aggregation of Calcium Oxalate Crystals In Vitro
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Sasindu Punyamali Hewagama and Ruwani Punyakanthi Hewawasam
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Technology ,Medicine ,Science - Abstract
Background. Deposition and formation of stones in any part of the urinary system is called urolithiasis. CaOx is the predominant component of most stones, and the formation of these stones is a multistep process that includes supersaturation, nucleation, aggregation, growth, and retention. In ayurvedic medicine, medicinal plants are used for the management of kidney stones. The objective of this study was to determine the effect of aqueous, ethanol, and hexane extracts of Drymoglossum piloselloides leaves, Kalanchoe laciniata leaves, and Aegle marmelos flowers against CaOx urolithiasis in vitro. Methods. The crystallization of CaOx monohydrate (COM) and dihydrate (COD) was induced in a synthetic urine system. The nucleation, growth, and aggregation of crystals were measured using spectrophotometric methods. The results were compared against the polyherbal drug, Cystone, under identical concentrations. Crystals generated in the urine were also observed under light microscopy. Statistical differences and percentage inhibitions were calculated using standard formulae and compared. A preliminary phytochemical screening was also performed to detect active phytoconstituents present in the three plants used in the study. Results. The results obtained clearly demonstrated that Kalanchoe laciniata, Aegle marmelos, and Drymoglossum piloselloides have the capacity to inhibit the nucleation, growth, and aggregation of CaOx crystals. Microscopic examination of crystals revealed the presence of more COM than COD crystals but a dose-dependent reduction in crystals was observed in the presence of plant extracts. Hexane, ethanol, and aqueous extracts of all three plants had different capabilities to inhibit nucleation, growth, and aggregation of CaOx crystals but their activities were different at different concentrations. Preliminary phytochemical screening revealed the presence of reducing sugars, proteins, flavonoids, tannins, and polyphenol compound in Kalanchoe laciniata and Drymoglossum piloselloides and reducing sugars, proteins, anthracene glycosides, and saponins in Aegle marmelos. Conclusions. This study provided evidence that Kalanchoe laciniata, Aegle marmelos, and Drymoglossum piloselloides have the potential to be developed as inhibitors of nucleation, growth, and aggregation of CaOx crystals in the treatment of urolithiasis.
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- 2022
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33. Audit of effect of spinal diamorphine and patient outcome
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G.G.C. Hewawasam and M. Sathialingam
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Anesthesiology ,RD78.3-87.3 - Published
- 2022
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34. A Novel Optimistic Local Path Planner: Agoraphilic Navigation Algorithm in Dynamic Environment
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Hasitha Hewawasam, Yousef Ibrahim, and Gayan Kahandawa
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Agoraphilic ,mobile robots ,navigation ,dynamic environment ,obstacle prediction ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
This paper presents a novel local path planning algorithm developed based on the new free space attraction (Agoraphilic) concept. The proposed algorithm is capable of navigating robots in unknown static, as well as dynamically cluttered environments. Unlike the other navigation algorithms, the proposed algorithm takes the optimistic approach of the navigation problem. It does not look for problems to avoid, but rather for solutions to follow. This human-like decision-making behaviour distinguishes the new algorithm from all the other navigation algorithms. Furthermore, the new algorithm utilises newly developed tracking and prediction algorithms, to safely navigate mobile robots. This is further supported by a fuzzy logic controller designed to efficiently account for the inherent high uncertainties in the robot’s operational environment at a reduced computational cost. This paper also includes physical experimental results combined with bench-marking against other recent methods. The reported results verify the algorithm’s successful advantages in navigating robots in both static and dynamic environments.
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- 2022
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35. Assessing Community Perceptions on Urban Flood Resilience in Sri Lanka
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Vindya Hewawasam and Kenichi Matsui
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flood vulnerability ,resilience ,community participation ,Sri Lanka ,climate disaster ,urban resilience ,Geology ,QE1-996.5 - Abstract
Urban communities’ perceptions about flood disasters can help better understand the resilience level of specific communities. This paper examines community-specific flood resilience by looking at Sri Lanka’s most flood-prone areas: the Kolonnawa and Kaduwela divisional secretariat divisions of Colombo. We conducted field surveys and a questionnaire survey among 120 community members. The collected questionnaire data were then analyzed partly by conducting multiple regression analyses. The results of our research identify varied perceptions about flood vulnerability and resilience by the community. Overall, our respondents regarded flood incidents as a high-risk disaster to their livelihoods, but some communities appeared to have higher coping strategies than others within the same administrative division. The respondents generally perceived that proximity to flood sources would increase flood vulnerability and frequency. Compared to other communities, Sedawatta community experienced most frequent floods, and 93% lived within 100 m from the river. The respondents had taken measures to mitigate floods mostly by elevating houses. Through multiple regression analyses, we found that education, income, household structure, distance to flood sources, and flood frequency had significant correlations with flood resilience and vulnerability in varying degrees by community. In conclusion, we argue that government flood management policies focus more on community-specific needs.
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- 2022
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36. A Novel Role for Somatostatin in the Survival of Mouse Pancreatic Beta Cells
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Erin L. Damsteegt, Zoheb Hassan, Nirun V. Hewawasam, Kittiwadee Sarnsamak, Peter M. Jones, and Astrid C. Hauge-Evans
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Physiology ,QP1-981 ,Biochemistry ,QD415-436 - Published
- 2019
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37. POS-184 Maternal characteristics and birth outcomes for mothers receiving kidney replacement therapy: An analysis of linked ANZDATA Registry and Perinatal datasets over 22 years
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E. HEWAWASAM, C. Davies, A. Gulyani, Z. Li, P. Clayton, E. Sullivan, S. McDonald, and S. Jesudason
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Diseases of the genitourinary system. Urology ,RC870-923 - Published
- 2021
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38. Blood cancer care in a resource limited setting during the Covid-19 outbreak; a single center experience from Sri Lanka.
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Saman Hewamana, Thurairajah Skandarajah, Chathuri Jayasinghe, Samadhi Deshapriya, Dhananjani Senarathna, Gehan Arseculeratne, Mahesh Harischandra, Gnani Somasundaram, Vadivelu Srinivasan, Surjit Somiah, Nihal Munasinghe, Sangeetha Hewawasam, Lalith Ekanayake, Rohini Wadanamby, Geethani Galagoda, Thet Thet Lin, and Jayantha Balawardena
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Medicine ,Science - Abstract
BackgroundThe Covid-19 pandemic has caused significant morbidity and mortality among patients with cancer. Most countries employed measures to prevent spread of Covid-19 infection which include shielding, quarantine, lockdown, travel restrictions, physical distancing and the use of personal protective equipment. This study was carried out to assess the change in patient attendance and the efficacy of newly implemented strategies to mitigate the impact of Covid-19 on services at the Lanka Hospital Blood Cancer Centre (LHBCC) in Colombo, Sri Lanka.MethodologyTelephone consultation, infection control, personal protective measures and emergency admission policy were implemented with the aim of having a Covid-19 free ward and to prevent cross-infections. This descriptive cross-sectional study was conducted with 1399 patient episodes (in-patient care or day-case review). We analysed patients treated as in-patient as well as day-case basis between 01st April 2020 and 31st December 2020.ResultsThere were 977 day-case based episodes and 422 in-patient based episodes. There was a 14% drop in episode numbers compared to same period in 2019. There was no cross infection and no patients with Covid-19 related symptoms or positive test results entered the LHBCC during the study period.ConclusionServices in blood cancer care were maintained to prevent late stage presentation and adverse outcome. Measures implemented to prevent Covid-19 were effective to allow continuation of treatment. This study highlights the importance of implementing strict protocols, clinical screening, use of appropriate personal protective equipment in delivering blood cancer care during the Covid-19 pandemic. This is the only documented study relating to outcome and successful applicability of measures to prevent spread of Covid-19 infection and maintaining services among blood cancer patients in Sri Lanka.
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- 2021
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39. Concordance between Body Composition Indices Measured with Dual-Energy X-Ray Absorptiometry and Bioelectrical Impedance Analysis in Obese Children in Sri Lanka
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Mawanane Hewa Aruna Devapriya de Silva, Ruwani Punyakanthi Hewawasam, and Sarath Lekamwasam
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Pediatrics ,RJ1-570 - Abstract
Dual-energy X-ray absorptiometry (DXA) is the reference standard in the measurement of body composition indices. But, its utility is limited due to the high cost, expertise required, lack of portability, and restricted availability. Therefore, bioelectrical impedance analysis (BIA) has gained recognition in resource-limited settings for the measurement of body composition indices in the screening of children for childhood obesity. To determine whether BIA represents a viable alternative to DXA in the assessment of body composition in obese children in the community setting in Sri Lanka, the concordance between BIA and DXA was determined. Fat mass (FM), percentage fat mass (%FM), and fat-free mass (FFM) were measured in 97 obese children using DXA and BIA, and the concordance between the methods was analyzed using independent sample t-test, regression analysis, and Bland-Altman plots. Significant mean differences were observed between DXA and BIA in measuring FM and FFM. However, high correlations were seen in DXA- and BMI-derived FM and FFM measurements (FM r=0.92 and FFM 0.83, P
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- 2021
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40. Traditional Water Governance Practices for Flood Mitigation in Ancient Sri Lanka
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Vindya Hewawasam and Kenichi Matsui
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tank cascade system ,dry zone ,water governance ,flood control ,traditional knowledge ,community participation ,Science - Abstract
The tank cascade system, which emerged as early as the fifth century BC in Sri Lanka’s dry zone, has been portrayed as one of the oldest water management practices in the world. However, its important function as flood management has not yet been thoroughly examined. In this paper, we argue that the main principle behind the tank cascade system is not only to recycle and reuse water resources by taking advantage of natural landscapes but also to control floods. This paper examines the evolution of traditional water management and flood mitigation techniques that flourished in pre-colonial Sri Lanka. This historical examination also sheds light on recent policies that exhibited renewed interests in revitalizing some aspects of the tank cascade system in Sri Lanka’s dry zone. This paper shows how ancient Sinhalese engineers and leaders incorporated traditional scientific and engineering knowledge into flood mitigation by engendering a series of innovations for land use planning, embankment designs, and water storage technologies. It also discusses how this system was governed by both kingdoms and local communities. Water management and flood control were among the highest priorities in urban planning and management. The paper thus discusses how, for centuries, local communities successfully sustained the tank cascade system through localized governance, which recent revitalized traditional water management projects often lack.
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- 2022
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41. Parenthood and pregnancy in Australians receiving treatment for end-stage kidney disease: protocol of a national study of perinatal and parental outcomes through population record linkage
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Elizabeth Sullivan, Erandi Hewawasam, Aarti Gulyani, Christopher E Davies, Sally Wark, Philip A Clayton, Stephen P McDonald, and Shilpanjali Jesudason
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Medicine - Abstract
Introduction Achieving parenthood is challenging in individuals receiving renal replacement therapy (RRT; dialysis or kidney transplantation) for end-stage kidney disease. Decision-making regarding parenthood in RRT recipients should be underpinned by robust data, yet there is limited data on parental factors that drive adverse health outcomes. Therefore, we aim to investigate the perinatal risks and outcomes in parents receiving RRT.Methods and analysis This is a multijurisdictional probabilistic data linkage study of perinatal, hospital, birth, death and renal registers from 1991 to 2013 from New South Wales, Western Australia, South Australia and the Australian Capital Territory. This study includes all babies born ≥20 weeks’ gestation or 400 g birth weight captured through mandated data collection in the perinatal data sets. Through linkage with the Australian and New Zealand Dialysis and Transplant (ANZDATA) registry, babies exposed to RRT (and their parents) will be compared with babies who have not been exposed to RRT (and their parents) to determine obstetric and fetal outcomes, birth rates and fertility rates. One of the novel aspects of this study is the method that will be used to link fathers receiving RRT to the mothers and their babies within the perinatal data sets, using the birth register, enabling the identification of family units. The linked data set will be used to validate the parenthood events directly reported to ANZDATA.Ethics and dissemination Ethics approval was obtained from Human Research Ethics Committees (HREC) and Aboriginal HREC in each jurisdiction. Findings of this study will be disseminated at scientific conferences and in peer-reviewed journals in tabular and aggregated forms. De-identified data will be presented and individual patients will not be identified. We will aim to present findings to relevant stakeholders (eg, patients, clinicians and policymakers) to maximise translational impact of research findings.
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- 2020
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42. Comparison of In Vitro Antibacterial Activity of Epaltes divaricata and Vetiveria zizanioides against Methicillin-Resistant Staphylococcus aureus
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Hasanga Rathnayake, Manikkuwadura Hasara Nethmini De Zoysa, Ruwani Punyakanthi Hewawasam, and Weerasinghe Mudiyanselage Dilip Gaya Bandara Wijayaratne
- Subjects
Medicine ,Science - Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of hospital- and community-acquired infections worldwide. Therefore, this study was conducted to explore the antibacterial activity of the two medicinal plants Epaltes divaricata and Vetiveria zizanioides against strains of MRSA which were isolated from patients with skin and soft tissue infections. Hexane, ethanol, and water extracts of E. divaricata (whole plant) and V. zizanioides (roots) were prepared. Clinical isolates of MRSA strains (n = 20) were used for the study. Bacterial susceptibility was tested using a disc diffusion assay. Minimum inhibitory concentration (MIC) was determined by a broth microdilution method. Vancomycin was used as the positive control. Hexane, ethanol, and water extracts of E. divaricata showed inhibitory zones against MRSA. Except for water extract, both hexane and ethanol extracts of V. zizanioides showed inhibitory zones. MIC ranges of hexane, ethanol, and water extracts in E. divaricata were 0.012–0.32 mg/mL, 0.019–2.4 mg/mL, and 0.019–0.48 mg/mL, respectively. Respective MIC ranges of hexane and ethanol extracts of V. zizanioides were 0.003–0.032 mg/mL and 0.019–2.4 mg/mL. The hexane extract of V. zizanioides inhibited 55% of the selected MRSA strains at a relatively low MIC value of 0.012 mg/mL. The hexane extract of both plants demonstrated inhibition of 75% of MRSA strains at a MIC value of 0.064 mg/mL. Ethanol extract of V. zizanioides and E. divaricata, respectively, inhibited 70% and 45% of MRSA strains at the MIC of 0.096 mg/mL, whereas water extract of E. divaricata inhibited 80% of MRSA strains at the same MIC. Both E. divaricata and V. zizanioides were equally effective against MRSA at a MIC of 0.064 mg/mL. But V. zizanioides was more effective since the hexane extract inhibited more than 50% of MRSA strains at significantly a lower MIC value of 0.012 mg/mL. Fractionation, purification, and identification of active compounds will warrant further evaluation of the therapeutic potential of both plant extracts.
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- 2020
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43. Modulation of Rab7a-mediated growth factor receptor trafficking inhibits islet beta cell apoptosis and autophagy under conditions of metabolic stress
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Hewawasam, Nirun V., Lhaf, Fadel, Taylor, Henry A., Viloria, Katrina, Austin, Amazon, King, Aileen, Jones, Peter, Jones, Lucy, Turner, Mark D., and Hill, Natasha J.
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- 2020
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44. Is leishmaniasis adequately notified in Sri Lanka? A survey among doctors from an endemic district, Sri Lanka
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Hewawasam, Chandana, Weerakoon, Hema S., Thilakan, Vyshnavi, Lelwala, Tishni, Prasanka, Kalana, Rathnayaka, A. S., Gamage, Shanika, and Agampodi, Suneth
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- 2020
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45. Long Noncoding RNA FENDRR Inhibits Lung Fibroblast Proliferation via a Reduction of β-Catenin
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Lakmini Kumari Senavirathna, Yurong Liang, Chaoqun Huang, Xiaoyun Yang, Gayan Bamunuarachchi, Dao Xu, Quanjin Dang, Pulavendran Sivasami, Kishore Vaddadi, Maria Cristina Munteanu, Sankha Hewawasam, Paul Cheresh, David W. Kamp, and Lin Liu
- Subjects
FENDRR ,SRSF9 ,mTOR signaling ,β-catenin ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive, and usually lethal lung disease and it has been widely accepted that fibroblast proliferation is one of the key characteristics of IPF. Long noncoding RNAs (lncRNAs) play vital roles in the pathogenesis of many diseases. In this study, we investigated the role of lncRNA FENDRR on fibroblast proliferation. Human lung fibroblasts stably overexpressing FENDRR showed a reduced cell proliferation compared to those expressing the control vector. On the other hand, FENDRR silencing increased fibroblast proliferation. FENDRR bound serine-arginine rich splicing factor 9 (SRSF9) and inhibited the phosphorylation of p70 ribosomal S6 kinase 1 (PS6K), a downstream protein of the mammalian target of rapamycin (mTOR) signaling. Silencing SRSF9 reduced fibroblast proliferation. FENDRR reduced β-catenin protein, but not mRNA levels. The reduction of β-catenin protein levels in lung fibroblasts by gene silencing or chemical inhibitor decreased fibroblast proliferation. Adenovirus-mediated FENDRR transfer to the lungs of mice reduced asbestos-induced fibrotic lesions and collagen deposition. RNA sequencing of lung tissues identified 7 cell proliferation-related genes that were up-regulated by asbestos but reversed by FENDRR. In conclusion, FENDRR inhibits fibroblast proliferation and functions as an anti-fibrotic lncRNA.
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- 2021
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46. Determination of In Vitro Antimicrobial Activity of Five Sri Lankan Medicinal Plants against Selected Human Pathogenic Bacteria
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Manikkuwadura Hasara Nethmini De Zoysa, Hasanga Rathnayake, Ruwani Punyakanthi Hewawasam, and Weerasinghe Mudiyanselage Dilip Gaya Bandara Wijayaratne
- Subjects
Microbiology ,QR1-502 - Abstract
Introduction. Antibiotic resistance is one of the greatest threats of the 21st century. Scientists search for potential antimicrobial sources that can cope with antibiotic resistance. Plants used in traditional medicine can be identified as potential candidates for the synthesis of novel drug compounds to act against antibiotic-resistant bacteria. Objective. To determine the potential antimicrobial effects of ethanol, aqueous, and hexane extracts of five Sri Lankan medicinal plants against four human pathogens. Methods. Asparagus falcatus (tubers), Asteracantha longifolia (whole plant), Vetiveria zizanioides (roots), Epaltes divaricata (whole plant), and Coriandrum sativum (seeds) were used in the study. Plant extracts were screened against four clinically important Gram-positive and Gram-negative bacterial strains, Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), and Klebsiella pneumoniae (ATCC 700603). Antibacterial activity of plant extracts were monitored using the agar disc diffusion method. Eight concentrations of each positive plant extract were used to determine the minimum inhibitory concentration (MIC) by 5-fold dilution of plant extracts yielding a serial dilution of the original extract. Results. Ethanol, aqueous, and hexane extracts of E. divaricata gave the maximum zones of inhibition of 16.3 mm, 7.4 mm, and 13.7 mm and MIC values of 0.48 mg/ml, 1.2 mg/ml, and 1.6 mg/ml, respectively, against S. aureus. Ethanol and hexane extracts of V. zizanioides gave the maximum zones of inhibition of 12.1 mm and 11.4 mm and MIC values 2.4 mg/ml and 0.003 mg/ml, respectively, against S. aureus. None of the other plants were effective against any microorganism used for the study. Conclusions. It can be concluded that E. divaricata and V. zizanioides crude ethanol, aqueous, and hexane extracts exhibited significant in vitro antibacterial activity against S. aureus, and the active compounds isolated from them can be potential sources for the synthesis of antibacterial drugs.
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- 2019
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47. Cord Leptin, C-Peptide and Insulin Levels in Large for Gestational Age Newborns in Sri Lanka
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Mawanane Hewa Aruna Devapriya De Silva, Ruwani Punyakanthi Hewawasam, and Mampitiya Arachchige Gayani Iresha
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Pediatrics ,RJ1-570 - Abstract
Background. Large for gestational age (LGA) infants are more prone to be obese and are at a higher risk of metabolic complications later in life. It is established that Asians have lower skeletal muscle mass and excess body fat for a given body mass index. Thus, objective of this study was to determine the relationship between leptin, insulin, C-peptide in cord blood on the birth weight of newborns and to determine whether these parameters are deviated from data already published from other populations. Methods. Umbilical cord blood was collected from 90 newborns (male 50, gestational age 38–42 weeks) which comprise of 43 LGA and 47 appropriate for gestational age (AGA) newborns. Serum leptin, insulin and C-peptide levels were measured and anthropometric parameters of the newborn and maternal characteristics were recorded. Results. Significantly higher (P
- Published
- 2019
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48. In vitro evaluation of the antimicrobial activity of leaf extracts of Litsea iteodaphne against a selected group of bacteria including methicillin-resistant Staphylococcus aureus
- Author
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Uyanahewa Gamage Shashini Janesha, Hasanga Rathnayake, Ruwani Punyakanthi Hewawasam, and Weerasinghe Mudiyanselage Dilip Gaya Bandara Wijayaratne
- Subjects
antibacterial efficacy ,crude extracts ,ethanol extract ,litsea iteodaphne ,minimum inhibitory concentration ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Background: The quest for scientific endorsement of new drugs from plants continues due to the rising antibiotic resistance against pathogenic bacteria. Litsea iteodaphne is used in Sri Lanka in the treatment of infectious diseases. Therefore, in vitro antibacterial activity of L. iteodaphne plant extracts were evaluated against selected human pathogenic bacteria. Materials and Methods: Antibacterial activity of 400, 40, and 4 mg/ml concentrations of hexane, ethanol, and aqueous leaf extracts of L. iteodaphne were evaluated against Staphylococcus aureus, Psedomona s aeruginosa, Klebsiella pneumoniae, Escherichia coli, and methicillin-resistant S. aureus (MRSA) clinical isolates using disc diffusion method. Minimum inhibitory concentration (MIC) was identified, and phytochemical screening was carried out. Results: Significant zones of inhibition ranging from 5.7 mm to 8.1 mm, 7.1 mm to 8.0 mm, and 7.6 mm were obtained for ethanol, hexane, and aqueous extracts at 400 mg/ml, respectively, against above four bacteria. For MRSA clinical isolates, zones of inhibition ranging from 6.1 mm to 10.9 mm, 6.7 mm to 10.8 mm, and 6.4 mm to 8.6 mm were obtained for ethanol, hexane, and aqueous extracts at 400 mg/ml, respectively. Ethanol extract of L. iteodaphne showed the lowest MIC value (0.0256 mg/ml). Phytochemical screening revealed the presence of tannins, cardiac glycosides, reducing sugars, phenolic compounds, saponins, and flavonoids. Conclusions: L. iteodaphne crude leaf extracts showed promising antibacterial activity against Gram-positive and Gram-negative bacteria and clinical isolates of MRSA. Further investigations toward fractionation and the identification of an active compound will enhance the antimicrobial potential of L. iteodaphne.
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- 2020
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49. Effect of Maternal Lipid Levels during Late Pregnancy on the Birth of Large for Gestational Age Newborns in a Tertiary Care Setting in Southern Sri Lanka
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Amarasingha Arachchige Dinusha Subhashini Amarasingha, Mohamed Fassy Fathima Nasrina, Ruwani Punyakanthi Hewawasam, Mawananehewa Aruna Devapriya De Silva, and Mampitiya Arachchige Gayani Iresha
- Subjects
asians ,childhood obesity ,lipid profile ,Medicine - Abstract
Introduction: Incidence of childhood obesity is increasing worldwide and obesity related comorbidities are also increasing simultaneously in the paediatric population. During pregnancy, growth of the foetus is highly influenced by the in utero environment. It is established that Asians have lower skeletal muscle mass and excess body fat for a given Body Mass Index (BMI). Aim: To determine the associations between aetiologies and the birth of Large for Gestational Age (LGA) babies for the first time in a tertiary care setting in Southern Sri Lanka and to determine whether changes in maternal lipid profile are associated with the birth of LGA babies. Materials and Methods: In the first arm of the study, 149 mothers were interviewed to obtain information on aetiologies and complications associated with birth of LGA babies. In the second arm of the study, 3 mL of blood was collected from 104 mothers and serum total cholesterol, triglycerides and HDLcholesterol concentration were measured and LDL cholesterol concentration was calculated by the Friedewald equation. Anthropometric parameters of the newborns were measured. Results: There were significantly higher levels (p
- Published
- 2018
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50. The PICTURE-C exoplanetary imaging balloon mission: a refactored thermal model and framework for an end-to-end model for balloon borne coronagraphs
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Barto, Allison A., Keller, Fanny, Stahl, H. Philip, Potter, Thaddeus, Mendillo, Christopher, Hewawasam, Kuravi, Martel, Jason, Cook, Timothy, and Chakrabarti, Supriya
- Published
- 2023
- Full Text
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