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Shopping as a daily activity that involves carrying shopping bags in hands might be associated with risk factors contributing to the development of low back pain (LBP) and strains and sprains in the upper extremity. A three-way repeated measures experiment was conducted for the purpose of the study. The independent variables were holding style, carrying technique, and shopping bags' weights. The dependent variables were cardiac cost, muscles' activities as a percentage of their maximum voluntary contraction's EMG (%MVC), peak plantar pressure (PPP), and discomfort rating. Carrying grocery bags with both hands to the sides of the body using shopping bags' holder was favorable and advantageous to other carrying conditions in terms of less cardiac cost, less %MVC, less peak plantar pressure, and less discomfort. It is useful to carry grocery bags close to the body with both hands using holders that are available in the local market.

Incremental sheet forming is a specific group of sheet forming methods that enable the manufacture of complex parts utilizing computer numerical control instead of specialized tools. It is an incredibly adaptable operation that involves minimal usage of sophisticated tools, dies, and forming presses. Besides its main application in the field of rapid prototyping, incremental sheet forming processes can be used for the manufacture of unique parts in small batches. The goal of this study is to broaden the knowledge of the deformation process in single-point incremental forming. This work studies the deformation behavior in single-point incremental forming by experimentally investigating the principal stresses, principal strains, and thinning of single-point incremental forming products. Conical-shaped components are fabricated using AA1050-H14 aluminum alloy at various combinations of fundamental variables. The factorial design is employed to plan the experimental study and analysis of variance is conducted to analyze the results. The grey relational analysis approach coupled with entropy weights is also implemented to identify optimum process variables for single-point incremental forming. The results show that the tool diameter has the greatest effect on the thinning of the SPIF product, followed by the sheet thickness, step size, and feed rate.

Arsenite (As(III)) and Selenate (Se(VI)) are universally touted as extremely toxic oxyanions in natural and industrial water systems. Thus, the production of low-cost adsorbents that are scalable and toxic-free is of great importance today. In this work, a large-scale goethite nanorods (α-FeOOH NRs) is synthesized using a modified rapid hydrolysis method. The obtained powder is characterized using different multidisciplinary techniques. Accordingly, the results showed uniform and straight nanorods (length ~400 nm and diameter ~40 nm) resembling cigar-like morphology while the structure is confirmed to be of orthorhombic α-FeOOH phase. The potential application of this material to adsorb As (III) and Se (VI) ions in water is explored. In particular, for initial adsorbate concentrations (~500 µg/L), the removal efficiencies are found exceptional with α-FeOOH doses of 0.33 g/L and ~0.5 g/L for As (III) and Se (VI), respectively. Attractively, the adsorption capacities were estimated using trusted isotherms and then experimentally verified at ultimately high concentrations. Besides, a pH-controlled adsorption study showed that a pH of 5–8 is a favored range for higher ionic uptake, which meets the World Health Organization (WHO) benchmarks of drinking water. To conclude, the α-FeOOH NRs are potential adsorbent for the sustainable removal of toxin ions in water systems.

The findings support the importance of accounting for nonlinear dynamical properties of biomechanical responses to lifting tasks.

According to the available literature, workers in hot climate countries, similar to the study cohort, can heat acclimatize faster than those in other Western countries.

Objective: This study evaluated participants' ability to assemble a computer keyboard while at a cycling workstation. Depending on task completion time, error percentage, and workload based on subjective workload ratings, subjective body discomfort, electroencephalography (EEG) and electrocardiographic (ECG) signals, human performances were compared at four different cycling conditions: no cycling, low level cycling (15 km/h), preferred level cycling, and high level cycling (25 km/h). Method: The experiment consisted of 16 participants. Each participant performed the test four times (each cycling condition) on different days. Results: The repeated measure test showed that the alpha and beta EEG signals were high during session times (post) when compared with session times (pre). Moreover, the mean interbeat (R-R) interval decreased after the participants performed the assembly while pedaling, possibly due to the physical effort of cycling. Conclusions: Pedaling had no significant effect on body discomfort ratings, task errors, or completion time.

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