265 research outputs found
Epidemiological, clinical and laboratory characteristics of 19 serologically confirmed rickettsial disease in Singapore.
AIM: To identify epidemiological, clinical and laboratory features of serologically-proven typhus in the local setting. METHOD & RESULTS: Retrospective study looking at rickettsial serologies done over a six-month period and collection of the epidemological, clinical, laboratory and treatment response data from the case notes of the patients with an ordered rickettsial serology. Twenty of the 35 cases had a positive serology. Of these 20 patients, 18 were already clinically diagnosed as having murine typhus. All except one were males and all were migrant workers. Majority of the patients were construction workers staying in containers where rats abound. The most consistent clinical features were high fever (100%) for a median period of seven days, headache (94%) and cough (47%). The white cell count was usually normal (74%) but thrombocytopenia was common (68%). Transaminitis was also common (90%) with the AST component higher than the ALT in half of the cases. Response to doxycycline therapy was rapid and most (88%) were afebrile by 72 hours. CONCLUSION: Typhus (notably murine type) can be confidently diagnosed from consistent clinical features supported by epidemiological and laboratory clues. Early recognition with the prompt treatment response will result in shorter hospital stay with decreased cost. Serological testing may only prove useful in difficult situations when the clinical diagnosis is less clear
Urea-Hydroxyapatite Nanohybrids for Slow Release of Nitrogen
While slow release of chemicals has been widely applied for drug delivery, little work has been done on using this general nanotechnology-based principle for delivering nutrients to crops. In developing countries, the cost of fertilizers can be significant and is often the limiting factor for food supply. Thus, it is important to develop technologies that minimize the cost of fertilizers through efficient and targeted delivery. Urea is a rich source of nitrogen and therefore a commonly used fertilizer. We focus our work on the synthesis of environmentally benign nanoparticles carrying urea as the crop nutrient that can be released in a programmed manner for use as a nanofertilizer. In this study, the high solubility of urea molecules has been reduced by incorporating it into a matrix of hydroxyapatite nanoparticles. Hydroxyapatite nanoparticles have been selected due to their excellent biocompatibility while acting as a rich phosphorus source. In addition, the high surface area offered by nanoparticles allows binding of a large amount of urea molecules. The method reported here is simple and scalable, allowing the synthesis of a urea-modified hydroxyapatite nanohybrid as fertilizer having a ratio of urea to hydroxyapatite of 6:1 by weight. Specifically, a nanohybrid suspension was synthesized by coating of hydroxyapatite with urea at the nanoscale. In addition to the stabilization imparted due to the high surface area to volume ratio of the nanoparticles, supplementary stabilization leading to high loading of urea was provided by flash drying the suspension to obtain a solid nanohybrid. This nanohybrid with a nitrogen weight of 40% provides a platform for its slow release. Its potential application in agriculture to maintain yield and reduce the amount of urea used is demonstrated.Authors thank Hayleys Agro Ltd., Sri Lanka for initiating this research programme at SLINTEC and Nagarjuna Fertilizer and Chemical Ltd (NFCL), India for providing further support. Authors acknowledge Mr Sunanda Gunesekara of SLINTEC for assistance with scaling up the production process to enable the field trials. ARK acknowledges the financial support received from ICTPELETTRA Users Program, Trieste, Italy to conduct photoemission experiments at Materials Science beam line (MSB) and ELETTRA SRS on HA and urea coated HA samples. ARK further acknowledges Dr. R.G. Acres of MSB beam line for his extensive support to conduct photoemission experiments. We acknowledge the Department of Agriculture and Rice Research and Development Institute of Sri Lanka, in particular Dr Priyantha Weerasinghe, Mr D Sirisena and Dr Amitha Benthota for the assistance in carrying out pot and farmers filed trials. NFCL and Central Salt & Marine Chemicals Research Institute, Gujarat, India for TEM and BET analysis
A Case Study of the Past, Present and Future of the Sesath Industry of Unaveruwa
Handicrafts represent a unique aspect of art in Asian cultures. They are a living cultural heritage that still continues in today's society. Handicrafts that use natural raw materials and simple techniques are excellent in quality and decoration as an end product. Sesath is one such traditional product in our country. At present, the traditional practice of Sesath making this is limited to only one region in Sri Lanka. Research problem is "What are the challenges to the continuity of Sesath industry in Unaveruwa?" Therefore, the aim of this study is to study the current nature of the traditional Sesath industry and the challenges faced by the industry in its continuity. The study area is Unaveruwa village in the Matale district. Interviews were conducted with 20 artisans and obtained information through field observations. Among the results of the study, Sesath has become a consumer product of the upper class of society in Sri Lanka. It was confirmed that the traditional Sesath industry in Unaveruwa is dying out. In the past, the youth have also shown interest in learning about the industry. There was no gender difference in Sesath making and the youth assisted the older artisans. In this way, the traditional knowledge of Sesath making passed to the next generation. But at present, the youth no longer assist the older artisans. The continuity of this traditional craft industry is seriously threatened due to the inability to purchase graphite, the main raw material, the lack of interest of the youth to join and continue this craft industry and not having a market for the products. Unaveruwa is located between two world heritage cities of Anuradhapura and Kandy. Sigiriya, a well-known World Heritage site, is located in Matale district. However, there are no initiatives in Unaveruwa to attract these tourists and sell their products to the tourists and local visitors. It would be beneficial to implement such programmes with government support to protect this traditional craft technology. Furthermore, it is suggested to encourage undergraduates who are studying archeology and fine arts to learn about such a dying tradition in order to preserve as an intangible cultural heritage in Sri Lanka
Spiritual Leadership and Employee Innovative Behaviour: An Empirical Study of the Banking Sector in Matale District of Sri Lanka
This study seeks to investigate the levels of spiritual leadership and the innovative behaviours exhibited by employees, analyze the interrelationship between these constructs, and examine the impact of spiritual leadership on the innovative behaviours of employees within the banking sector. Empirical data were gathered through structured questionnaires which were administered to 208 employees from five distinct banks in Matale district of Sri Lanka, thereby addressing a notable gap in existing empirical literature within this specific research sphere. The findings reveal the prevalence of both spiritual leadership and employee innovative behaviour at a high level in the surveyed banks. In addition, the findings also indicated a positive correlation between spiritual leadership and employee innovative behaviour. Importantly, the analysis revealed that spiritual leadership exerts a significant influence on the innovative behaviour of employees in the surveyed banks. These insights contribute to understanding the role of leadership styles in fostering innovation in organizational settings.
Key Words: Employee, Innovative Behaviour, Leadership, Spiritual Leadershi
The safe use of metformin in heart failure patients both with and without T2DM: A cross-sectional and longitudinal study.
AIMS: This study investigated the safe use of metformin in patients with (1) type 2 diabetes mellitus (T2DM) and heart failure on metformin, and (2) heart failure without T2DM and metformin naïve. METHODS: Two prospective studies on heart failure patients were undertaken. The first was a cross-sectional study with two patient cohorts, one with T2DM on metformin (n = 44) and one without T2DM metformin naive (n = 47). The second was a 12-week interventional study of patients without T2DM (n = 27) where metformin (500 mg immediate release, twice daily) was prescribed. Plasma metformin and lactate concentrations were monitored. Individual pharmacokinetics were compared between cohorts. Univariable and multivariable analysis analysed the effects of variables on plasma lactate concentrations. RESULTS: Plasma metformin and lactate concentrations mostly (99.9%) remained below safety thresholds (5 mg/L and 5 mmol/L, respectively). Metformin concentration had no significant relationship with lactic acidosis safety markers. In the interventional study, New York Heart Association (NYHA) II (P < .03) and III (P < .001) grading was associated with higher plasma lactate concentrations, whereas male sex was associated with 47% higher plasma lactate concentrations (P < .05). The pharmacokinetics of heart failure patients with and without T2DM were similar. CONCLUSIONS: We observed no unsafe plasma lactate concentrations in patients with heart failure treated with metformin. Metformin exposure did not influence plasma lactate concentrations, but NYHA class and sex did. The pharmacokinetics of metformin in heart failure patients are similar irrespective of T2DM. These findings may support the safe use of metformin in heart failure patients with and without T2DM
Design of MRI Structured Spiking Neural Networks and Learning Algorithms for Personalized Modelling, Analysis, and Prediction of EEG Signals
Abstract This paper proposes a novel method and algorithms for the design of MRI structured personalized 3D spiking neural network models (MRI-SNN) for a better analysis, modeling, and prediction of EEG signals. It proposes a novel gradient-descent learning algorithm integrated with a spike-time-dependent-plasticity algorithm. The models capture informative personal patterns of interaction between EEG channels, contrary to single EEG signal modeling methods or to spike-based approaches which do not use personal MRI data to pre-structure a model. The proposed models can not only learn and model accurately measured EEG data, but they can also predict signals at 3D model locations that correspond to non-monitored brain areas, e.g. other EEG channels, from where data has not been collected. This is the first study in this respect. As an illustration of the method, personalized MRI-SNN models are created and tested on EEG data from two subjects. The models result in better prediction accuracy and a better understanding of the personalized EEG signals than traditional methods due to the MRI and EEG information integration. The models are interpretable and facilitate a better understanding of related brain processes. This approach can be applied for personalized modeling, analysis, and prediction of EEG signals across brain studies such as the study and prediction of epilepsy, peri-perceptual brain activities, brain-computer interfaces, and others
Bioactive plasma coatings on orthodontic brackets: In Vitro metal ion release and cytotoxicity
The metal ion release characteristics and biocompatibility of meta-based materials are key factors that influence their use in orthodontics. Although stainless steel-based alloys have gained much interest and use due to their mechanical properties and cost, they are prone to localised attack after prolonged exposure to the hostile oral environment. Metal ions may induce cellular toxicity at high dosages. To circumvent these issues, orthodontic brackets were coated with a functional nanothin layer of plasma polymer and further immobilised with enantiomers of tryptophan. Analysis of the physicochemical properties confirmed the presence of functional coatings on the surface of the brackets. The quantification of metal ion release using mass spectrometry proved that plasma functionalisation could minimise metal ion release from orthodontic brackets. Furthermore, the biocompatibility of the brackets has been improved after functionalisation. These findings demonstrate that plasma polymer facilitated surface functionalisation of orthodontic brackets is a promising approach to reducing metal toxicity without impacting their bulk properties.Lasni Samalka Kumarasinghe, Neethu Ninan, Panthihage Ruvini Lakshika Dabare, Alex Cavallaro, Esma J. Dogramacı, Giampiero Rossi-Fedele ... et al
Thermoelectric power factor under strain-induced band-alignment in the half-Heuslers NbCoSn and TiCoSb
Band convergence is an effective strategy to improve the thermoelectric
performance of complex bandstructure thermoelectric materials. Half-Heuslers
are good candidates for band convergence studies because they have multiple
bands near the valence bad edge that can be converged through various band
engineering approaches providing power factor improvement opportunities.
Theoretical calculations to identify the outcome of band convergence employ
various approximations for the carrier scattering relaxation times (the most
common being the constant relaxation time approximation) due to the high
computational complexity involved in extracting them accurately. Here, we
compare the outcome of strain-induced band convergence under two such
scattering scenarios: i) the most commonly used constant relaxation time
approximation and ii) energy dependent inter- and intra-valley scattering
considerations for the half-Heuslers NbCoSn and TiCoSb. We show that the
outcome of band convergence on the power factor depends on the carrier
scattering assumptions, as well as the temperature. For both materials
examined, band convergence improves the power factor. For NbCoSn, however, band
convergence becomes more beneficial as temperature increases, under both
scattering relaxation time assumptions. In the case of TiCoSb, on the other
hand, constant relaxation time considerations also indicate that the relative
power factor improvement increases with temperature, but under the energy
dependent scattering time considerations, the relative improvement weakens with
temperature. This indicates that the scattering details need to be accurately
considered in band convergence studies to predict more accurate trends.Comment: 21 pages, 8 figures. arXiv admin note: text overlap with
arXiv:1905.0795
Validation of a physician global assessment tool for vitiligo extent: Results of an international vitiligo expert meeting
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