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Membranes with PVA, enzymes, and PVC-KTpClPB contribute as pores on the indicator electrode of potentiometric cells to produce voltage. This study aimed to characterize membranes modified with PVA, enzymes, and PVC-KTpClPB as urea sensors. Membrane modification was done in three variations: membrane A (0.504 g of PVA, 0.504 g of PVC, 1 mg of enzymes, and 0.012 g of KTpCIPB), membrane B (0.035 g of PVA, 0.035 g of PVC, 1 mg of enzymes, and 0.012 g of KTpCIPB), and membrane C (0.035 g of PVA, 0.035 g of PVC, 1 mg of enzymes, and 0.050 g of KTpCIPB). The analysis was performed using UV-Visible to obtain the best membranes, namely membrane A and C. The preparation of electrodes was carried out using membrane A and C with various PVA coatings, such as one coating for membrane electrode A1 and C1, two coatings for membrane electrode A2 and C2, and three coatings for membrane electrode A3 and C3. XRD analysis was performed to obtain the best membrane electrode which was the membrane electrode C2. Based on the measurement analysis of electrode membrane in the potentiometric cells with electrochemical techniques, the sensitivity obtained was 19.069 mV/decade with a confidence level of R2 = 0.9434 in the range of 1.10-5-5.10-4 M and detection limit of 1.10-5M. [ABSTRACT FROM AUTHOR]

Analysis of the steady-state and reactivity insertion accident is very important for the safety of reactor operations. In this study, steady-state and reactivity insertion accident analysis when the low enriched uranium foil target is irradiated in the reactor core has been carried out. The analysis is carried out by the best estimate method by using a coupled neutronic, kinetic, and thermal-hydraulic code, MTR-DYN. The MTR-DYN code is based on the 3-D multigroup neutron diffusion method. The cell calculations for the target are carried out by the WIMSD/5 and MTR-DYN code. After reactivity insertion, the coolant, fuel, and clad temperature are observed. The calculation results for the initial power of 1 W showed that the maximum temperature of the coolant, clad, and fuel are 49.76°C, 65.01°C, and 65.26°C, respectively. Meanwhile, when the reactivity insertion at the initial power of 1 MW, the maximum temperature of the coolant, clad, and fuel are 72.23°C, 140.79°C, and 141.97°C, respectively. Based on those calculation results during irradiation low enriched uranium foil target, the temperature in the steady-state and reactivity insertion accident does not exceed the allowable safety limit.

Reservoirs and lakes are widely used for fisheries, both capture fisheries and aquaculture. Aquaculture fisheries that develop in reservoirs or lakes include floating net cages culture (FCC) and pen culture. Besides impacting the economy and employment opportunities, aquaculture activities through FCC can decrease water quality from uneaten feed and fish metabolism residue. For this reason, an environmentally friendly FCC is needed to reduce aquaculture waste. This paper reviews the development of ecologically friendly FCC research in Indonesia. Several studies on environmentally friendly FCC include double net FCC, bio-cages, carpel FCC, windowed, and triple layer FCC. Double net FCC still allows the remaining uneaten feed and feces to settle. Bio-cage research is in the innovation model stage and has no prototype or laboratory tests. Windowed FCC, made with a closed system and a few gaps for circulation, can accommodate aquaculture waste and not spread into the waters, but fish grow slower than other FCC. The loop bio-phytoremediation of FCC or Smart FCC has three layers that can accommodate waste, and the waste will be used for plants that function as filters and phytoremediators of waste. Smart FCC is an aquaponic system modified to be applied in reservoirs/lakes.

The Indonesian Multipurpose Research Reactor namely Reaktor Serba Guna G.A. Siwabessy (RSG GAS) is a 30 MWth (max.) pool-type reactor loaded with plate-type low-enriched uranium fuel, using light water as coolant and moderator, and beryllium as reflector. The benchmark of the 1st criticality core of RSG GAS using different nuclear data libraries such as JENDL-4.0, JENDL-3.3, ENDF/B-VII.0, and JEFF-3.1 have been performed in the previous work and compared with the experiment result. In this work, the newly released ENDF/B-VIII.0 neutron reaction and thermal neutron scattering libraries will be used and the important neu-tronics parameters such as multiplication factor, kinetics parameters, and fission reaction rate will be calculated using Monte Carlo code MCNP6.2 and compared against the previous work and the experiment result.

The electroplating industry generates wastewater containing a variety of heavy metals which potentially contaminate water ecosystems. The available and well-known electroplating wastewater treatments are considered as an expensive and less effective method, therefore phytoremediation was used as an alternative friendly solution. This study aims to evaluate the uptake and elimination rate of heavy metals by vetiver (Chrysopogon zizanoides L.) on metal-polluted water. Vetiver was planted in artificial electroplating wastewater containing different levels (low, medium, high) of chromium (Cr) and nickel (Ni). Water, roots, and shoots were collected periodically to determine Cr and Ni contents using Atomic Absorption Spectrometry (AAS). Metal accumulation and elimination rate, Bioconcentration Factor (BCF), Biological Absorption Coefficient (BAC), and Translocation Factor (TF) were calculated to evaluate plant's effectiveness in metal remediation processes. The results showed that vetiver (C. zizanoides L.) was able to remove 61.10% Cr and 95.65% Ni on metal-contaminated water. The highest uptake rates for Cr and Ni are 127.21 mg/kg/day and 15.60 mg/kg/day respectively, while the elimination rates for Cr and Ni tend to slow 1.09 mg/kg/day and 12.24 mg/kg/day respectively. Vetiver BCF, BAC, and TF values on Cr and Ni contaminated water were greater than 1, which indicates that vetiver work through phytoextraction and phytostabilization to treat metals. The findings showed that vetiver has promise as a phytoremediation agent thus providing implication for electroplating wastewater treatment., (© 2021. The Author(s).)

The aquaponic system is an alternative strategy to treat aquaculture waste and achieve food independence. Bacteria play vital roles in the aquaponic system as they can transform ammonia or ammonium into nitrite and then into nitrate, which is more favorable for bacteria, fish, and plants. The objective of this study was to determine the effect of nitrifying bacteria (Nitrosomonas europaea Winogradsky and Nitrobacter winogradskyi Winslow) on the aquaponic system in terms of water quality, nutrient availability, and productivity of carp (Cyprinus carpio), lettuce (Lactuca sativa var. crispa), and vetiver grass (Chrysopogon zizanioides L.). The experiment consisted of four treatments: aquaculture of carp as a control for fish (A), hydroponic of lettuce and vetiver grass without nutrient addition as a control for plants (B), aquaponic (carp, lettuce, vetiver grass) (C), and aquaponic with nitrifying bacteria addition (D). The results showed nitrifying bacteria addition had a significant effect on daily growth rate (DGR) and relative growth rate (RGR) of lettuce within a treatment; on the other hand, the nitrifying bacteria did not give a significant effect to RGR of vetiver grass. The growth rate, specific growth rate, and survival rate of the carp in aquaculture treatment (A) were lower than in both aquaponic treatments (C and D). Nitrifying bacteria addition in the aquaponics system had a significant effect of increasing the orthophosphate concentration. Water quality was also indicated to be better in the aquaponic system than in the aquaculture system. The integration of aquaculture and hydroponics with the addition of nitrifying bacteria enables the formation of microorganism communities, nitrate, and orthophosphate, which lead to the improvement of water quality, nutrient availability, and plant growth.

Background: Atopic dermatitis or eczema is one of the most common dermatologic problems, especially in children. Several studies have hypothesized that alteration of gut-colonizing microbes might have induced and conditioned the development of the disease. Thus, modulation of microbial diversity and abundance might help alleviate symptoms and conditions for patients. Given the ability of commensal and symbiotic microorganisms in modulating the immune system, probiotics administration has been studied in previous research in the management of eczema. However, until today, there are conflicting results between studies making inconclusive recommendations towards probiotics supplementation in the management of atopic dermatitis. This case-based review was done to assess and evaluate the therapeutic efficacy of probiotics supplementation in the management of eczema in children., Method: An electronic database search was conducted in PubMed-NCBI, Cochrane, EBSCO, ProQuest, and SCOPUS in March 2020. Individual studies and reviews were then gathered for screening using predetermined inclusion and exclusion criteria. The included studies were then critically appraised for their validity and importance., Result: A total of 5 studies, all of which were RCTs, were included in this review. Out of all the studies included, 4 showed no clinically significant improvements in using probiotics in the management of eczema in children as they did not pass the minimal clinically important difference (MCID) of eczema severity as determined by SCORAD (SCORing Atopic Dermatitis)., Conclusion: Supplementation of probiotics in the management of eczema in children does not show a clinically relevant difference vs. standard treatment in reducing eczema severity., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Ashila Putri Disamantiaji et al.)