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The Federation of Asian and Oceanian Biochemists and Molecular Biologists (FAOBMB) and the College of Biochemists of Sri Lanka (CBSL) organized a virtual education symposium in 2021 funded by the International Union of Biochemistry and Molecular Biology (IUBMB). The parallel session named "Students' Perception" was attended by 188 participants from 11 countries. The main objectives of this session were to aggregate participants' viewpoints on aspects of virtual education, including innovative strategies to enhance motivation and engagement of students, improving teacher-student and student-student interactions, managing stress, and virtual learning platforms. Data were collected via rapporteurs from multiple segments of the session including a mini-introductory talk, poll, role play, and discussions about outstanding student experiences, types of virtual platforms, innovative methods of teaching, student motivation and stress management. The importance of student perception and issues like technological difficulties and the reluctance of students to engage were discussed. In addition to well-established strategies such as using polls, chat box features, and discussions in breakout rooms, participants also proposed exciting learning methods to engage students such as quizzes, competitions and challenges, engagement of multiple sensory modalities, story-based learning, and so forth. This report provides anecdotal evidence on pedagogies described in textbooks and also introduces new ideas based on this existing foundation. Future research should aim to harmonize virtual education with traditional classroom methods and explore innovative virtual tools like avatar-based universities, virtual labs, and user-friendly online assessment platforms. The results apply to all disciplines, and not exclusively to biochemistry and molecular biology (BMB).

Abstract Wolbachia bacteria are common endosymbionts of insects and have recently been applied for controlling arboviral vectors, especially Aedes aegypti mosquito populations. However, several medically important mosquito species in Sri Lanka were present with limited information for the Wolbachia infection status. Therefore, the screening of Wolbachia in indigenous mosquitoes is required prior to a successful application of Wolbachia-based vector control strategy. In this study, screening of 78 mosquito species collected from various parts of the country revealed that 13 species were positive for Wolbachia infection, giving ~ 17% infection frequency of Wolbachia among the Sri Lankan mosquitoes. Twelve Wolbachia-positive mosquito species were selected for downstream Wolbachia strain genotyping using Multi Locus Sequencing Type (MLST), wsp gene, and 16S rRNA gene-based approaches. Results showed that these Wolbachia strains clustered together with the present Wolbachia phylogeny of world mosquito populations with some variations. Almost 90% of the mosquito populations were infected with supergroup B while the remaining were infected with supergroup A. A new record of Wolbachia supergroup B infection in Ae. aegypti, the main vectors of dengue, was highlighted. This finding was further confirmed by real-time qPCR, revealing Wolbachia density variations between Ae. aegypti and Ae. albopictus (p = 0.001), and between males and females (p

IntroductionSri Lanka implemented the National Programme for Elimination of Lymphatic Filariasis (NPELF) in its endemic regions in 2002. Five annual rounds of mass drug administration using the two-drug combination diethylcarbamazine (DEC) and albendazole led to sustained reductions in infection rates below threshold levels. In 2016, WHO validated that Sri Lanka eliminated lymphatic filariasis as a public health problem.ObjectiveTo explore the impact of the NPELF on lymphatic filariasis morbidity in Sri Lanka.MethodsPassive Case Detection (PCD) data maintained in filaria clinic registries from 2006-2022 for lymphoedema and hospital admission data for managing hydroceles/spermatoceles from 2007-2022 were analyzed. The morbidity status in 2022 and trends in overall and district-wise PCD rates were assessed. Poisson log-linear models were used to assess the trends in PCD for endemic regions, including district-wise trends and hospital admissions for the management of hydroceles/spermatoceles.ResultsIn 2022, there were 566 new lymphoedema case visits. The mean (SD) age was 53.9 (16.0) years. The staging was done for 94% of cases, of which 79% were in the early stages (57.3% and 21.4% in stages two and one, respectively). Western Province had the highest caseload (52%), followed by the Southern (32%) and Northwestern (16%) Provinces, respectively. The reported lymphoedema PCD rate in 2022 was 0.61 per 10,000 endemic population. The overall PCD rate showed a decline of 7.6% (95%CI: 4.9% - 10.3%) per year (P < 0.0001) from 2007 to 2022. A steady decline was observed in Colombo, Gampaha and Kurunegala districts, while Kalutara remained static and other districts showed a decline in recent years. Further, admissions for inpatient management of hydroceles/spermatoceles showed a declining trend after 2015.ConclusionsThe PCD rates of lymphoedema and hydroceles/spermatoceles showed a declining trend in Sri Lanka after the implementation of the NPELF.

Dendrocalamus asper (giant bamboo) is a clumping type of bamboo belonging to the Poaceae family. Due to its economic and environmental value, demand for this species has increased tremendously. Conventional propagation methods have limitations due to low seed viability and the lack of healthy clumps. Therefore, an in vitro mass propagation protocol was developed to provide healthy plants for large-scale plantations. Seeds were used as the explant and they were surface sterilized and cultured on MS medium free of growth regulators. Nodal segments taken from in vitro germinated seedlings were used for shoot initiation. The best medium for shoot induction (MS medium supplemented with 0.0–2.5 mg/L BAP), best medium for multiple shoot induction (MS medium supplemented with 0.0–5.0 mg/L BAP), effect of shoot cluster size (shoot clusters containing 1–4 shoots) and effect of physical state of the medium (semisolid and liquid media) on multiple shoot induction were determined using shoots per node, mean shoot length and mean number of leaves per shoot after 6 weeks of incubation. Elongated shoots were transferred into a rooting medium and the best medium for root induction (MS medium supplemented with 0.0–5.0 mg/L IBA and IAA) and effect of cluster size (shoot clusters containing 1–4 shoots) on rooting were determined using the number of roots and root length after 6 weeks of incubation. All the cultures were maintained under a 16-hour photoperiod. Well-developed plantlets were transferred to coir pellets and after four weeks transferred into different potting mixtures containing different combinations of sand, compost and coir dust. Unless otherwise mentioned there were at least twenty replicates in all treatments. The highest mean number of shoots per node (16.87±0.52), mean shoot length (4.12±0.27 cm) and mean number of leaves per shoot (4.80±0.33) were observed in the MS medium supplemented with 1.0 mg/L BAP. The MS medium supplemented with 2.0 mg/L BAP was the best for multiple shoot induction, shoot cluster with 3 shoots was the best cluster size and the liquid medium had a better effect on shoot multiplication. The half-strength MS medium supplemented with 2.0 mg/L IBA was the best for in vitro root induction with the highest mean number of roots (7.15±0.77) and a mean root length of 10.79±1.11 cm. Shoot clusters with 3 shoots was the best cluster size for root induction. A sand: compost: coir dust (1:1:1) mixture was the best potting mixture giving 100% survival. These findings provide a reliable micropropagation protocol for D. asper, which holds great promise for meeting the growing demand for bamboo resources and promoting sustainable bamboo cultivation.

Wildfires have destroyed multiple residential communities in California in recent years. After fires in 2017 and 2018, high concentrations of benzene and other volatile organic compounds (VOCs) were found in public drinking water systems in fire-affected areas. The sources of the contamination and appropriate remediation have been urgent matters for investigation. This study characterizes target and non-target VOCs and semi volatile organic compounds (SVOCs) in water from a highly contaminated service line after the 2018 Camp Fire (Paradise, CA). Ninety-five organic compounds were identified or tentatively identified in the service line. Laboratory combustion experiments with drinking water pipes made of polyvinyl chloride (PVC), cross-linked polyethylene (PEX) and high-density polyethylene (HDPE) and a review of the literature were used to evaluate potential sources of the detected chemicals. Among the service line contaminants were thirty-two compounds associated with PVC pyrolysis and twenty-eight organic compounds also associated with the pyrolysis of polyethylene. The service line sample also contained fifty-five compounds associated with uncontrolled burning of biomass and waste materials. The findings support hypotheses that wildfires can contaminate drinking water systems both by thermal damage to plastic pipes and intrusion of smoke. Residual chlorine disinfectant in the water system modifies the contaminant distribution observed.

Helminths are major etiologic agents of human blindness in low-income countries (1). Adult, juvenile, and larval stages of nematodes, cestodes, and trematodes have been recovered from ocular and periocular tissues. [...]

Using histopathology and phylogenetic analysis of the internal transcribed spacer 2 gene, we found >2 distinct trematode species that caused ocular trematode infections in children in Sri Lanka. Collaborations between clinicians and parasitologists and community awareness of water-related contamination hazards will promote diagnosis, control, and prevention of ocular trematode infections.

Control of structural coupling at complex-oxide interfaces is a powerful platform for creating ultrathin layers with electronic and magnetic properties unattainable in the bulk. However, with the capability to design and control the electronic structure of such buried layers and interfaces at a unit-cell level, a new challenge emerges to be able to probe these engineered emergent phenomena with depth-dependent atomic resolution as well as element- and orbital selectivity. Here, we utilize a combination of core-level and valence-band soft x-ray standing-wave photoemission spectroscopy, in conjunction with scanning transmission electron microscopy, to probe the depth-dependent and single-unit-cell resolved electronic structure of an isovalent manganite superlattice [Eu0.7Sr0.3MnO3/La0.7Sr0.3MnO3]×15 wherein the electronic-structural properties are intentionally modulated with depth via engineered oxygen octahedra rotations/tilts and A-site displacements. Our unit-cell resolved measurements reveal significant transformations in the local chemical and electronic valence-band states, which are consistent with the layer-resolved first-principles theoretical calculations, thus opening the door for future depth-resolved studies of a wide variety of heteroengineered material systems.

Introduction and objectives: Sri Lankans do not have a specific cardiovascular (CV) risk prediction model and therefore, World Health Organization(WHO) risk charts developed for the Southeast Asia Region are being used. We aimed to develop a CV risk prediction model specific for Sri Lankans using machine learning (ML) of data of a population-based, randomly selected cohort of Sri Lankans followed up for 10 years and to validate it in an external cohort. Material and methods: The cohort consisted of 2596 individuals between 40–65 years of age in 2007, who were followed up for 10 years. Of them, 179 developed hard CV diseases (CVD) by 2017. We developed three CV risk prediction models named model 1, 2 and 3 using ML. We compared predictive performances between models and the WHO risk charts using receiver operating characteristic curves (ROC). The most predictive and practical model for use in primary care, model 3 was named "SLCVD score" which used age, sex, smoking status, systolic blood pressure, history of diabetes, and total cholesterol level in the calculation. We developed an online platform to calculate the SLCVD score. Predictions of SLCVD score were validated in an external hospital-based cohort. Results: Model 1, 2, SLCVD score and the WHO risk charts predicted 173, 162, 169 and 10 of 179 observed events and the area under the ROC (AUC) were 0.98, 0.98, 0.98 and 0.52 respectively. During external validation, the SLCVD score and WHO risk charts predicted 56 and 18 respectively of 119 total events and AUCs were 0.64 and 0.54 respectively. Conclusions: SLCVD score is the first and only CV risk prediction model specific for Sri Lankans. It predicts the 10-year risk of developing a hard CVD in Sri Lankans. SLCVD score was more effective in predicting Sri Lankans at high CV risk than WHO risk charts. [ABSTRACT FROM AUTHOR]

Abstract The pharmacological treatment of depression consists of stages of trial and error, with less than 40% of patients achieving remission during first medication trial. However, in a large, randomized-controlled trial (RCT) in the U.S. (“GUIDED”), significant improvements in response and remission rates were observed in patients who received treatment guided by combinatorial pharmacogenomic testing, compared to treatment-as-usual (TAU). Here we present results from the Canadian “GAPP-MDD” RCT. This 52-week, 3-arm, multi-center, participant- and rater-blinded RCT evaluated clinical outcomes among patients with depression whose treatment was guided by combinatorial pharmacogenomic testing compared to TAU. The primary outcome was symptom improvement (change in 17-item Hamilton Depression Rating Scale, HAM-D17) at week 8. Secondary outcomes included response (≥50% decrease in HAM-D17) and remission (HAM-D17 ≤ 7) at week 8. Numerically, patients in the guided-care arm had greater symptom improvement (27.6% versus 22.7%), response (30.3% versus 22.7%), and remission rates (15.7% versus 8.3%) compared to TAU, although these differences were not statistically significant. Given that the GAPP-MDD trial was ultimately underpowered to detect statistically significant differences in patient outcomes, it was assessed in parallel with the larger GUIDED RCT. We observed that relative improvements in response and remission rates were consistent between the GAPP-MDD (33.0% response, 89.0% remission) and GUIDED (31.0% response, 51.0% remission) trials. Together with GUIDED, the results from the GAPP-MDD trial indicate that combinatorial pharmacogenomic testing can be an effective tool to help guide depression treatment in the context of the Canadian healthcare setting (ClinicalTrials.gov NCT02466477).

Objective: To assess public knowledge, practices and perceptions on typhus fevers in Sri Lanka. Methods: A descriptive study was done in four selected typhus- prone areas in Southern Sri Lanka. A mixed-method was employed using face-to-face interviews and questionnaire-based surveys among confirmed cases of typhus and at-risk populations, respectively. Frequencies, percentages, and means were used to characterize socio-demography and evaluate disease awareness. Results: The lay terms for typhus fevers reported in the studied region were “peacock fever”, “tick fever” and “bird fever”. A total of 499 subjects participated [mean±SD, (45±16) years] in the questionnaire-based survey, and 13.6% (n=68) reported past experience of typhus fever, 1.2% (n=6) identified the disease as “typhus” while 58.7% (n=293) and 11.8% (n=59) knew it as ‘peacock fever’ and ‘tick fever’, respectively. The etiological agent was unknown to 95.2% (n=475), but 53.5% ((n=267) were aware that it was vector-borne. Fever (57.3%, n=286), eschar (35.7%, n=178), headache (22.0%, n=267) and myalgia (19.2%, n=96) were identified as key symptoms. Past disease experience was significantly associated with higher awareness of the main disease symptoms (fever: χ2=15.713, P

Rational design of low-dimensional electronic phenomena at oxide interfaces is currently considered to be one of the most promising schemes for realizing new energy-efficient logic and memory devices. An atomically abrupt interface between paramagnetic LaNiO3 and antiferromagnetic CaMnO3 exhibits interfacial ferromagnetism, which can be tuned via a thickness-dependent metal-insulator transition in LaNiO3. Once fully understood, such emergent functionality could turn this archetypal Mott-interface system into a key building block for the above-mentioned future devices. Here, we use depth-resolved standing-wave photoemission spectroscopy in conjunction with scanning transmission electron microscopy and x-ray absorption spectroscopy, to demonstrate a depth-dependent charge reconstruction at the LaNiO3/CaMnO3 interface. Our measurements reveal an increased concentration of Mn3+ and Ni2+ cations at the interface, which create an electronic environment favorable for the emergence of interfacial ferromagnetism mediated via the Mn4+-Mn3+ ferromagnetic double exchange and Ni2+-O-Mn4+ superexchange mechanisms. Our findings suggest a strategy for designing functional Mott oxide heterostructures by tuning the interfacial cation characteristics via controlled manipulation of thickness, strain, and ionic defect states.

Solution-based growth of magnetic FePt-FeCo (core-shell) nanoparticles with a controllable shell thickness has been demonstrated. The transition from spin canting to exchange coupling of FePt-FeCo core-shell nanostructures leads to a 28% increase in the coercivity (12.8 KOe) and a two-fold enhancement in the energy product (9.11 MGOe).

The nature of the metal-insulator transition in thin films and superlattices of LaNiO3 only a few unit cells in thickness remains elusive despite tremendous effort. Quantum confinement and epitaxial strain have been evoked as the mechanisms, although other factors such as growth-induced disorder, cation non-stoichiometry, oxygen vacancies, and substrate-film interface quality may also affect the observable properties of ultrathin films. Here we report results obtained for near-ideal LaNiO3 films with different thicknesses and terminations grown by atomic layer-by-layer laser molecular beam epitaxy on LaAlO3 substrates. We find that the room-temperature metallic behavior persists until the film thickness is reduced to an unprecedentedly small 1.5 unit cells (NiO2 termination). Electronic structure measurements using X-ray absorption spectroscopy and first-principles calculation suggest that oxygen vacancies existing in the films also contribute to the metal-insulator transition.

Background: Non-adherence to antipsychotics in schizophrenia is associated with an increased risk of psychotic relapse and hospitalization, a risk that is reduced with the use of long-acting injectable (LAI) antipsychotics. Randomized clinical trials (RCTs) have demonstrated the efficacy of paliperidone palmitate 3-monthly (PP3M) for psychotic relapse prevention in schizophrenia, but it remains poorly documented among individuals treated in real-life settings who can benefit the most out of LAIs. Objectives: The objective of this study was to evaluate the effectiveness of PP3M in relapse prevention among patients with schizophrenia. Methods: This is a multicentre retrospective study conducted in four outpatients’ clinics across Canada. All consecutive patients with a main diagnosis of schizophrenia who initiated PP3M between June 2016 and March 2020 were included. The primary outcome was psychotic relapse, defined using broad and clinically relevant criteria. Results: Among 178 consecutive patients who were switched to PP3M, the 12-month relapse rate was 18.5% and the relapse-free survival probability was 0.788 (95% confidence interval [CI] = 0.725–0.856). Comorbid diagnoses of personality disorders and substance use disorders were associated with hazard rates (HRs) of 3.6 (95% CI = 1.8–7.3, p