The use of activated carbon from natural material such as coconut shell charcoal as metal absorbance of the wastewater is a new trend. The activation of coconut shell charcoal carbon by using chemical-physical activation has been investigated. Coconut shell was pyrolized in kiln at temperature about 75 - 150 °C for about 6 hours in producing charcoal. The charcoal as the sample was shieved into milimeter sized granule particle and chemically activated by immersing in various concentration of HCl, H3PO4, KOH and NaOH solutions. The samples then was physically activated using horizontal furnace at 400°C for 1 hours in argon gas environment with flow rate of 200 kg/m3. The surface morphology and carbon content of activated carbon were characterized by using SEM/EDS. The result shows that the pores of activated carbon are openned wider as the chemical activator concentration is increased due to an excessive chemical attack. However, the pores tend to be closed as further increasing in chemical activator concentration due to carbon collapsing.

The stunting prevalence in Indonesia is still above the WHO minimum standard of 20%. An important aspect of early detection of stunting is to monitor the nutritional status of children under five periodically. In daily practice, nutritional status is obtained through anthropometry. The main anthropometric parameters are body mass, height, and head circumference. This research entails the development of an integrated and non-contact anthropometric system for measuring body mass, height, and head circumference for children aged 12–60 months. This non-contact method can prevent the transmission of infectious diseases, especially during the COVID-19 pandemic. For the development of a prototype, three types of sensors are used: load, proximity, and temperature sensor. In addition, a load cell sensor is used to measure body mass, an infrared sensor to measure height and head circumference, ultrasonic sensor to measure height. In addition, the anthropometric system developed is equipped with an MLX90614-DCI sensor to measure temperature, a thermal printer to print measurement results, and sound output. The results of the tests showed that this anthropometric system had an average error less than 5%. Therefore, it is suitable to measure the body mass, height, and head circumference of children under five.

Delayed union and nonunion fractures are clinical challenges for orthopedic surgeons. The development of fracture complications, such as delayed union and nonunion fractures, is still difficult to predict. Various methods are being investigated to improve fracture healing and prevent complications in patients. There are various methods to promote fracture healing, broadly divided into biological, chemical, and physical methods. One of the most widely used physical methods to promote fracture healing is the pulsed electromagnetic field (PEMF). This study aimed to evaluate the healing process of delayed union fracture after being stimulated by PEMF. Twenty-four rats were randomly divided into two groups: the control group (n=12) and the PEMF group (n=12). Delayed union fracture was performed on the left femur of all rats. Subsequently, the PEMF group was given PEMF stimulus with a magnetic field intensity of 1.6mT and a frequency of 50Hz for 4 hours/day and 7 days/week. The fracture healing process was evaluated on days 5, 10, 18, and 28 based on the bone callus histology using safranin O fast green (SOFG) staining. The results of the histological analysis showed that bone cartilage was higher in the PEMF group than in the control group throughout the observation period. In addition, the PEMF group had less fibrous tissue at the beginning of the healing. This finding indicates PEMF stimulation has an effect on inducing osteogenesis on fracture healing and reducing the risk of delayed union.

The adsorption of activated carbon of coconut shell charcoal on heavy metals (Cu and Fe) of the wastewater and its relation with the carbon pore structure was investigated. The coconut shell was pyrolized in kiln at temperature about 75 - 150 °C for about 6 hours to produce charcoal and then shieved into milimeter sized granule particles. Chemical activation was done by immersing the charcoal into chemical solution of KOH, NaOH, HCl and H₃PO₄, with various concentration. The activation was followed by physical activation using horizontal furnace at 400°C for 1 hours in argon gas environment with flow rate of 200 kg/m³. The surface morphology of activated carbon were characterized by using Scanning Electron Microscopy (SEM). Wastewater was made by dissolving CuSO₄.5H₂O and FeSO₄.7H₂O into aquades. The metal adsorption was analized by using Atomic Absorption Spectroscopy (AAS). The result shows that in general, the increase of chemical concentration cause the increase of pore number of activated carbon due to an excessive chemical attack and lead the increase of adsorption. However it tend to decrease as further increasing in chemical activator concentration due to carbon collapsing. In general, the adsorption of Cu and Fe metal from wastewater by activated carbon increased as the activator concentration was increased.

Dyslipidemia is a condition of abnormalities in blood lipids, such as increased LDL and decreased HDL. Exposure to intracellular static magnetic fields (SMFs) can affect membranes to modulate the number of Ca²⁺ ions, which can affect cell biological effects. Increasing the number of Ca²⁺ ions will affect the expression of genes that help reduce LDL levels as an indicator of CHD. This study aims to see whether the influence of SMFs can affect calcium levels, lipid profiles, SREBP-2 protein excretion, and LDLR gene expression, which affects the process of breaking down cholesterol. We used obese C57BL/6J male mice divided into standard and HFD feed groups. The HFD feed group was split into Obes0, Obes2, Obes7, Obes14, and Obes21 groups based on the day of exposure. The exposure was carried out with an intensity of Bmax = 2 mT for 1 h daily. After exposure to SMFs, there were changes in blood cholesterol and LDL levels, which tended to decrease in the Obes2 and Obes7 groups and increase in the Obes14 and Obes21 groups. In addition, the exposed group tended to have an increase in the expression of the LDLR gene, SREBP-2 protein, and calcium ion compared to the control. Although it managed to increase after exposure on days 14 and 21, there was a decrease in the expression of the LDLR gene and SREBP-2 protein; hence, the effect of SMF exposure can reduce the risk of CHD. However, research still needs to be done regarding the effective duration of exposure.

One way to use technology in learning is by using Simulation Physics Education and Technology (PhET). This article describes the results of the development of an electronic module for learning physics about elasticity and Hooke’s law in class XI SMA. This research method is Research and Development with ADDIE model. The steps in this development are making needs assessments, analyzing materials, designing electronic modules, developing assessment tools, realizing electronic module designs, product validation by experts, testing electronic modules by teachers and students and performing evaluations. Based on the needs analysis conducted in class XI MIPA SMAN 107 Jakarta on 58 students, the results were obtained: 98.23% of students have difficulty understanding the physics material during PJJ, 94.83% of students are interested in the use of electronic modules as a companion for self-study at home and 87.72% of the students chose a module with instructions for independent practicum. The electronic module supported by that simulation is an alternative teaching material that can be used by students for self-study and can be used to conduct virtual experiments. The results of this research have been validated by physicists, learning experts and media experts.