Factors Influencing Online Education during COVID-19 Pandemic: Sri Lankan Students’ Perspective

This study examines the factors influencing online education for selected Sri Lankan universities during the COVID-19 pandemic. It also analyses the moderate effect of gender and type of the university on online education. Primary data were collected using a questionnaire via google form from Management students in Sri Lankan selected universities. Data analysis was done through structural equations using analysis of moment structures (AMOS) version 22.0. Attitude, internet and related facilities, curriculum, and self-motivation were found to have a significant positive impact on online education, while workload & time have no significant effect on online education. Among four factors, the strongest influence was derived from self-motivation followed by the curriculum. We have not found significant differences among male and female students’ views on online education, while the impact from the type of university is different among the two categories. This study effectively guides policy makers and university administrators across the educational institutes to decide on continuing online education. It reveals some insights to the teachers, students, and parents to understand the significance of the modern online learning environment and its positive impact on the new learning mode. There is no study related to the factors associated with the impact of online education during the Covid-19 pandemic in the Sri Lankan context

Customer Satisfaction and Revisit Intention towards Fast Food Restaurants in Sri Lanka

This study aimed at examining factors that effect of food taste, food quality, service quality, perceived price, responsiveness, restaurant environment on customer satisfaction and revisit intention. Data were collected through a structured questionnaire survey of fast food restaurant customers in a selected metropolitan area from Colombo district and students from University of Sri Jayewardenepura. The data were analyzed using SPSS 21.0 and R Studio 3.5.1 software. The study has found that food quality and perceived price are the important antecedents of restaurant customer satisfaction. Further, the results clearly showed a significant role of customer satisfaction on revisit intention and crucial impact of perceived price on customer satisfaction. In addition, revisit intention towards the fast food restaurant is directly influenced by food tastes. This study collected data from two selected groups; students from University of Sri Jayewardenepura and one metropolitan area, and data has analyzed further based on demographic characteristics further to confirm the results.  Therefore, this study provides valuable insight to restaurant managers on attracting, retaining and satisfying their customers

IMPLEMENTATION OF GENERAL PROVISIONS ON OCCUPATIONAL HEALTH AND SAFETY IN THE FACTORY ORDINANCE (NO. 45 OF 1942) (A QUALITATIVE STUDY)

 In the late 1970s, Free Trade Zones were established in Sri Lanka as an important part of the economic development of the island. These zones were specially designated manufacturing areas which were set up to attract foreign investments to the country. In these places, occupational health and safety are vital features of the Human Resource Management. In the Sri Lankan context, studies regarding occupational health and safety are scarce. The general objective of this study was to explore the implementation of general provisions on occupational health, and safety in the Factory Ordinance (No. 45 of 1942) among workers in Katunayake Export Processing Zone. A qualitative approach was adapted to this study. The study consisted of two phases: in the first phase focus group discussion with workers were done, and in the second phase, ten in-depth interviews were conducted. Purposive sampling method was used to select participants from workers based on the inclusion criteria. Twenty workers (n=20) were selected from different factories in the zone. Saturation method was used as the guiding method of data collection. Data was analyzed using framework analysis. Study found that, implementation of general provisions on occupational health is remaining in a satisfactory level; implementing general provisions of occupational safety in work place is remaining at better status; however implementation of few provisions should be improved. A longitudinal study on occupational health and safety among factory workers and factory managers need to be conducted. In addition to that, improving awareness on Factories’ Ordinance (No. 45 of 1942) is recommended. Employers should also be empowered to intervene with managers for implementing general provisions and special provisions of occupational health and safety in the Factories’ Ordinance

SEED PROPAGATION OF RATH HADUN (Pferocarpus santalinus Linn.) AS EFFECTD BY METHOD OF SOAKING AND SCARIFICATION

Red Sandalwood (Pterocarpus santalinus Linn.) is an evergreen tree species grownunder semi dry climates in well drained lateric soils. The reddish and fragrant heartwoodhas a range of medicinal, pharmaceutical, industrial and timber and economically placedin the same category as tusk and amber. The Red heartwood contains a range ofconstituents including santalin (Santalic Acid), Santaol, Pterocarpin, Homo-Petrocarpinand reported to have anticoagulant, anti inflammatory, anti expectorant, anti pyretic, antibacterial and anti tumor properties. Expensive natural fabric paint produced from thepowdered Red heartwood is used in wood carving of prestigious nature. The naturalhabitat of Red Sandalwood is India which is extensively exploited to the point of nearextinction, thus placing it in the red list of endangered species under IUCN guidelinesThere is only a limited number of Red sandalwood trees in Sri Lanka, which werebrought from India. Therefore, conservation and multiplication of Red sandal wood is oftimely importance. Even though a single tree of Red Sandalwood produces severalthousands of seeds, there is no single seedling under the tree. The local requirement ofRed Sanders is met partly by Indian suppliers while substitutes with similar medicinalproperties (Rath Kehiriya) are also being used.Two separate pot experiments(Complete Randomized Design with three replicates) wereconducted to study the seed germination as affected by method of soaking andscarification. Fully matured brown coloured fresh seeds were used for the experimentsand viability of the seeds used for the experiment was 70 to 72 %. Three differentsoaking methods (i.e. 24 hours dipping in normal water, 24 hour soaking in runningwater, alternatively soaked in running water for 12 hrs. followed by 12 hours of dryingfor 14 days) and again differentiated with scarification and without scarification wereused as treatments. Total germination percentage was counted up to 14 daysResults revealed that Seed germination was significantly higher (P>0.05) in scarifiedseeds (48.8%) when compared to those without scarification (6.1%). With regards to thesoaking method, highest germination percentage (3 1%) was observed in the treatment,12 hrs of alternate soaking and drying in running water for 14 days, which was notsignificantly different from the treatment that seeds were soaked in running water for 24hrs. Therefore it can be concluded that germination of Red Sandalwood seeds could besubstantially enhanced by scarification of the seed coat and seeds soaked in runningwater for 24 hrs. as well as 12 hrs of alternate soaking and drying for 14 days.

Human epidermal growth factor receptor-2 gene expression positivity determined by silver in situ hybridization/immunohistochemistry methods and associated factors in a cohort of Sri Lankan patients with gastric adenocarcinoma : a prospective study

Objective: Positive human epidermal growth factor 2 (HER2) expression and its predictive clinicopathological features remain unclear in Sri Lankan gastric cancer (GC) patients. Here, we aimed to determine GC HER2 status predictors by analyzing associations between clinicopathological features and HER2 expression using immunohistochemistry (IHC) and silver in situ hybridization (SISH). Methods: During this 4-year prospective study, clinicopathological data were collected from participants in the National Hospital of Sri Lanka. HER2 IHC and SISH were performed using commercial reagents. Using chi-square tests, associations of HER2-IHC/SISH with clinicopathological features were analyzed. Results: Overall, 145 GC patients were included, 69 had gastrectomies and 76 had biopsies. Positive HER2 expression by IHC was associated with age 5/high-power field, with additional perineural invasion and lymphovascular invasion in resections. These features, excluding lymphovascular invasion but including male sex, were associated with HER2 expression by SISH. Conclusions: Age <60 years, high nuclear grade, tumor necrosis, and perineural invasion are associated factors of HER2 status. These could be used to triage GC patients for HER2 status testing in limited resource settings where IHC/SISH analysis is costly

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

Gapless spinons and a field-induced soliton gap in the hyper-honeycomb Cu oxalate framework compound [(C2_{2}H5_{5})3_{3}NH]2_{2}Cu2_{2}(C2_{2}O4_{4})3_{3}

We report a detailed study of the specific heat and magnetic susceptibility of single crystals of a spin liquid candidate: the hyper-honeycomb Cu oxalate framework compound [(C$_2$H$_5$)$_3$NH]$_2$Cu$_2$(C$_2$O$_4$)$_3$. The specific heat shows no anomaly associated with a magnetic transition at low temperatures down to $T\sim$ 180 mK in zero magnetic field. We observe a large linear-in-$T$ contribution to the specific heat $\gamma T$, $\gamma = 98(1)$ mK/mol K$^{2}$, at low temperatures, indicative of the presence of fermionic excitations despite the Mott insulating state. The low-$T$ specific heat is strongly suppressed by applied magnetic fields $H$, which induce an energy gap, $\Delta (H)$, in the spin-excitation spectrum. We use the four-component relativistic density-functional theory (DFT) to calculate the magnetic interactions, including the Dzyaloshinskii-Moriya antisymmetric exchange, which causes an effective staggered field acting on one copper sublattice. The magnitude and field dependence of the field-induced gap, $\Delta (H) \propto H^{2/3}$, are accurately predicted by the soliton mass calculated from the sine-Gordon model of weakly coupled antiferromagnetic Heisenberg chains with all parameters determined by our DFT calculations. Thus our experiment and calculations are entirely consistent with a model of [(C$_2$H$_5$)$_3$NH]$_2$Cu$_2$(C$_2$O$_4$)$_3$ in which anisotropic magnetic exchange interactions due to Jahn-Teller distortion cause one copper sublattice to dimerize, leaving a second sublattice of weakly coupled antiferromagnetic chains. We also show that this model quantitatively accounts for the measured temperature-dependent magnetic susceptibility. Thus [(C$_2$H$_5$)$_3$NH]$_2$Cu$_2$(C$_2$O$_4$)$_3$ is a canonical example of a one-dimensional spin-1/2 Heisenberg antiferromagnet and not a resonating-valence-bond quantum spin liquid, as previously proposed.Comment: 8 pages, 6 figure

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