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This paper reports an empirical study on the practice and effectiveness of online EFL teaching during COVID-19. Teachers had to shift to an online mode of teaching very suddenly with no previous experience and without much preparation. Their practices and effectiveness were investigated using the Technological Pedagogical and Content Knowledge (TPACK) theoretical model as the framework. A mixed method research design was planned and carried out in Bangladeshi universities using a web-based survey and indepth interviews. Data from 50 university English teachers highlight the need for a student-oriented perspective in teacher education and the creation of online teaching-based teacher development programmes (TDP) to enhance students' experiential learning in online platforms, in line with the 'learning technology by design' approach. More importantly, the element of "Context" (XK) and "Classroom Management Knowledge" (CMK) have emerged as important 'new' tenets of TPACK. Hence, a revised version of TPACK is suggested. Further research and discussions are advocated before it could be established and propagated as an acceptable version of TPACK. [ABSTRACT FROM AUTHOR]

Radon, an element of natural radiation, is considered one of the leading causes of lung cancer worldwide. In Bangladesh, radon has been clarified as a foremost source of radiation exposure. Potential natural-radiation-induced elevated cancer risks were estimated in Bangladesh previously for the population. In this survey, as a very preliminary study in the country, comparative indoor radon (222Rn, Rn) and thoron (220Rn, Tn) concentration/population exposure was determined for the multistoried dwellings of south-western areas of Dhaka city. RADUET was used to assess annual Rn and Tn concentrations in determining the primary inhalation dose for the population. The annual effective dose of Rn and Tn was evaluated in this study for dwellings at 0.3 mSvy−1, constituting a Tn dose contribution of an average of 40% with a dwelling-based wide range of 10–96%. Thus, Tn should not be neglected for Bangladesh while estimating radiological inhalation dose from the indoor environment. Again, the equilibrium factors, F of Rn and Tn, were determined by short-term measurement at averages of 0.6 and 0.02, respectively. Furthermore, using questionnaire estimation by principal component analysis, PCA following the dwelling characteristics, human lifestyles, and estimated long-term indoor Rn and Tn concentrations, this paper discussed indoor atmospheric/Rn factors for the investigated multistoried dwellings in Dhaka city. [ABSTRACT FROM AUTHOR]

To investigate the effect of cow dung and chemical fertilizers on the growth and yield performances of mungbean (BARI Mung 6), an experiment was carried out in the research field of the Sher-e-Bangla Agricultural University, Dhaka, during the kharif season of 2020. The experiment was laid out as a randomized complete block design (RCBD) with three replications comprising seven manure-fertilizer treatments. The results showed that the different levels of cow dung and fertilizers significantly influenced mungbean growth parameters and seed yield. The highest plant height (48.2 cm), number of leaves plant-1 (10.3), number of branches plant-1 (3.9), maximum number of pods plant-1 (19.3), seeds pod-1 (10.4), 1000-seed weight (43.4g), and the highest seed yield (1.42 t ha-1) were obtained from the application of 80% of the recommended dose of fertilizers (RDF) plus 20% cow dung. It is concluded that applying 20% cow dung (1.2 t ha-1) coupled with 80% of the recommended amount of fertilizers together produced superior results for the growth and yield of mungbean compared to applying fertilizer or cow dung alone. [ABSTRACT FROM AUTHOR]

Selection criteria is very crucial to pick up promising genotypes in a breeding program. An experiment was conducted with twenty soybean genotypes following a randomized complete block design to study the inheritable agronomic traits, their interrelation and partitioning of genotypic correlation into direct and indirect effects to identify the traits responsible for higher seed yield. Results indicated that phenotypic variance was higher than that of genotypic variance for all the characters. The highest PCV was found for the trait seed yield per plant (39.03%) followed by yield per plot (32.85%). The higher GCV was also found for the same traits-seed yield per plant (37.36%), yield per plot (27.23%). PCV and GCV was the lowest for trait days to maturity (6.28%, 4.16%) and days to flowering (3.20%, 2.24%). Estimated broad sense heritability was ranged from days to flowering (44.05%) to seed yield per plant (91.62%). Higher estimate of heritability was also observed for yield per plot (88.65%) followed by hundred seed weight (85.39%) whereas; heritability was moderate for plant height (76.75%) and pod per plant (70.17%). The genetic advance was the highest for plant height (19.39%). On the other hand, primary branch per plant, days to flowering and days to maturity showed low heritability with low GA depicts the influence of non-additive gene effect. Pod per plant, hundred seed weight, days to maturity and plant height is positively and significantly correlated with yield. Pod per plant (0.908) and hundred seed weight (0.907) showed highest direct positive effect on seed yield at genotypic level. Path analysis also confirmed highest positive direct effect of hundred seed weight (0.701). So, the present study suggests that, higher hundred seed weight and pod per plant can be effective selection measure for improvement of soybean yield. [ABSTRACT FROM AUTHOR]

Mechanical energy stored in an oscillating cantilever in frequency modulation atomic force microscopy (FM-AFM) was dissipated through nonconservative interactions between a sample and a tip on the cantilever. The energy dissipation (D dis) was measured using FM-AFM with a metal-coated tip for a metal-coated Si substrate partly covered with thin mica films. At tipâ€"sample separations where electrostatic force was dominant under a bias voltage, Joule heat was generated owing to the tip oscillation, responsible for D dis. From analysis of D dis and the frequency shift of the cantilever, electric resistance responsible for the Joule heat was estimated to be of the order of GΩ. The great values of the resistance were discussed in the terms of surface scattering of charges moved by the oscillating tip and the dielectric energy loss in the mica films. Measurement of the energy dissipation exhibited potential to probe the local surface electronic properties in non-contact. [ABSTRACT FROM AUTHOR]