Sawmill workers in Bangladesh are increasingly at risk of emerging work-related musculoskeletal disorders (WRMSDs). Their jobs involve awkward manual handling tasks such as lifting, carrying, pushing and pulling. These are identified as risk factors for musculoskeletal disorders. The aims of this study are to find out the prevalence of musculoskeletal disorders and assessing the postural risk level among sawmills workers. This cross-sectional study was conducted with 254 workers from 60 sawmills at the southern part of Bangladesh. The overall 70.1% of sawmills workers were suffering musculoskeletal disorders in at least one body part for the last one year. The average Rapid Entire Body Assessment (REBA) score of four main tasks (Pushing, Pulling, Lifting, and Carrying the timber) was 9.25, which is high risk for MSDs symptoms. The main reasons behind these MSDs are lack of knowledge about workplace safety, working postures and the settings of the workplace. We have recommended to the management to apply the NIOSH (National Institute for Occupational Safety and Health) lifting and Manual Material handling techniques; arrange OSHA (Occupational Safety and Health Administration) ergonomic training to the workers. Also, suggested designing the working table and workplaces in ergonomically to mitigate the musculoskeletal disorders.

This paper reports the comparative growth, nutritional performance, and morphometric variation between wild and hatchery-reared juvenile mud crabs (Scylla olivacea) in earthen ponds. The crabs were fed daily with boiled tilapia paste at a feeding rate of 5-8% body weight for the first two weeks, followed by feeding with chopped eviscerated tilapia until termination of the experiment. Selected phenotypic trains, including carapace width (CW), carapace length (CL) and abdominal width (AW), were measured weekly. The protein content of the muscle (21.13%), gill (13.51%) and egg (43.28%) were significantly higher in the hatchery-sourced compared to wild female crabs (muscle ¼ 19.15%; gill ¼ 10.09%; egg ¼ 38.15%). Likewise, the hatchery sourced crabs exhibited higher lipid content in the muscle (2.45-2.51%) and eggs (7.51%) compared to the wild counterparts (muscle ¼ 1.45-1.47%; egg ¼ 6.15%). These findings suggested a superior nutritional quality of the hatchery-reared compared to the wild-sourced crabs. Although some selected phenotypic traits did not vary among the wild and hatchery-reared crabs (p < 0.05), their survival rates varied significantly depending on the stocking density (p < 0.05). Overall, the findings suggest that the growth characteristics of the hatchery produced and wild-sourced crab were similar, which will help to remove the misconception among the crab farmers about the hatchery seeds and promote diversification of the crab production system for long-term sustainability.

Recently, InGaN grown on semipolar and non-polar orientation has caused special attraction due to reduction in the built-in polarization field and increased confinement of high energy states compared to traditional polar c-plane orientation. However, any widespread-accepted report on output power and frequency response of the InGaN blue laser in non-c-plane orientation is readily unavailable. This work strives to address an exhaustive numerical investigation into the optoelectronic performance and frequency response of In0.17Ga0.83N/GaN quantum well laser in polar (0001), non-polar (101¯0) and semipolar (101¯2), (112¯2) and (101¯1) orientations by working out a 6 × 6 k.p Hamiltonian at the Γ-point using the tensor rotation technique. It is noticed that there is a considerable dependency of the piezoelectric field, energy band gap, peak optical gain, differential gain and output power on the modification in crystal orientation. Topmost optical gain of 4367 cm−1 is evaluated in the semipolar (112¯2)-oriented laser system at an emission wavelength of 448 nm when the injection carrier density is 3.7 × 1018 cm−3. Highest lasing power and lowest threshold current are reported to be 4.08 mW and 1.45 mA in semipolar (112¯2) crystal orientation. A state-space model is formed in order to achieve the frequency response which indicates the highest magnitude (dB) response in semipolar (112¯2) crystal orientation.

In this work, an intermediate band solar cell (IBSC) model consisting of MAPbI3 quantum dots (QD) and MAPbCl3 barrier material is explored analytically with MATLAB. Titanium di-oxide (TiO2) is used as transport layer for electron and Spiro-OMeTAD (2,2',7,7'-tet-rakis (N,N'-di-p-methoxyphenylamine)–9,9' spirobifluorene) is used as transport layer for hole. Fluorine-doped tin oxide (FTO) and Silver (Ag) is used as top and bottom contact. The impact of QD size and dot spacing on the key parameters of MAPbI3 QD-IBSC is illustrated throughout this paper. In order to identify the number of IB in a single regime, Schrödinger equation is solved as a function of host energy gap using Kronig–Penney model. The detailed balance limit assumptions with unity fill factor are applied to extract highest efficiency from the system. For any case, face centered cubic (FCC) crystal structure is assumed. The (100) crystal orientation is considered as charge carriers from n–region to p–region transport in this orientation. Major performance indicators of the device such as photocurrent intensity Jsc, open circuit voltage Voc and power conversion efficiency η have been delineated. Highest efficiency of 63% is attained for dot size of 4 nm and dot spacing of 1.5 nm.