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An important application in spatiotemporal data analysis is spatiotemporal kriging, which seeks to recover signals for unobserved locations based on observed signals. The main challenge of the spatiotemporal kriging is how to effectively model and take use of the spatiotemporal dependencies within the data. In order to recover data for unsampled sensors on a network or graph structure, we implement an Inductive Graph Neural Network Kriging (IGNNK) with L1loss. We conducted an experiment using four real-world spatiotemporal datasets to demonstrate the effectiveness of our model. To evaluate how the IGNNK algorithm and to minimize the error value, we add L1loss function to the model and compare it with L2loss in hope to minimize the errors in the model. L1loss shrinks the less important features coefficient to zero, removing some feature altogether. Our results show that: in general, IGNNK achieves quite good performance on two spatial datasets: NREL and USHCN. We also obtained an interesting result that the increasing number of iterations on the IGNNK model using L1loss has a positive effect on the performance of the model. Specifically, the result shows a good effect on the average value of the MAE on the METR-LA (6.816), NREL (3.960) and USHCN (2.427) datasets as well as on the value of the RMSE on the NREL (5.657) dataset. Meanwhile, the average MAE value from SeData is 4.531, which is slightly lower than using L2 loss. [ABSTRACT FROM AUTHOR]

Leaves of Ficus deltoidea Jack. contains flavonoids, steroids, alkaloids, triterpenoids, saponins, tannins, and phenolics which beneficial as traditional medicines. However, level of safety for its use is unknown. Present study purposed to evaluate the subchronic toxicity of ethanolic extract of Ficus deltoidea Jack (FDEE) on the histology of ventriculus and intestinum tenue of male mice (Mus musculus). In total 25 mice were randomly divided into five treatment groups and treated with leaves of FDEE at doses of 0, 125, 250, 500, and 1000 mg/kg body weight (BW) for 28 days. At the end of the study, the mice were dissected, ventriculus and intestinal tenue organs were taken out and weighed. The organs of the ventriculus and intestinal tenue were prepared for histological preparations. The thickness of the ventriculus wall and the height of the intestinal villi were measured histologically. The results showed that there was no significantly changed on the histological structure of the ventriculus and intestinal tenue of mice treated with 125 and 250 mg/kg BW of FDEE leaves. Meanwhile, at doses of 500 and 1000 mg/kg BW, there was a slightly change on the histological of ventriculus which was indicated by the thickness of the ventriculus wall and the height of intestinal villi. The FDEE leaves above 500 mg/kg BW affected the thickness of the ventriculus wall and the height of the intestinal tenue villi of male mice. [ABSTRACT FROM AUTHOR]

The process of eliminating uranium and thorium in the deposition of rare earth carbonates from xenotime alkaline roasting. The purpose of this study is to eliminate U and Th in the deposition of rare earth carbonates from xenotime alkaline roasting. As much as 10 grams of xenotime sand was mixed with the variation of NaOH and (NH4)2CO3 ratio. Then the mixture was roasted at various temperatures. After that, it was leached using HCl solution. The leaching solution was precipitated using MgO and NH4OH. The deposition of the leaching solution was analyzed by XRF Epsilon 4 and XRF Ortec 7010. The parameters studied were pH of precipitation, roasting temperature, and the addition of compounds for the precipitation process. The result of this research is the optimal precipitation conditions using MgO and sodium carbonate. The precipitation efficiency of U and Th from rare earth carbonates respectively was 65.4% and 82%. [ABSTRACT FROM AUTHOR]

The synergistic solvent extraction of yttrium from acidic nitric solution was carried out using organophosphorus mixed extractants of di(-2-ethyl hexyl) phosphoric acid – tri-n-octyl phosphine oxide and Cyanex 572 – tributyl phosphate in kerosene diluent. The effect of the concentration ratio between each of the extractants on the synergism phenomenon of the yttrium extraction process was investigated. This experiment was performed by dissolving yttrium concentrate in aqueous HNO3 then it is extracted using D2EHPA, TOPO, a mixture of D2EHPA - TOPO, Cyanex 572, TBP, and also a mixture of Cyanex 572 - TBP in kerosene diluent, at various concentrations with the ratio aqueous phase: organic phase=1: 1 until the equilibrium conditions. The result showed that a slight synergism phenomenon occurs in extraction using a mixture of di(-2-ethyl hexyl) phosphoric acid - tri-n-octyl phosphine oxide extractants as indicated by a range of synergistic coefficient (S) values between 1.0179 - 1.7047. The stronger synergism phenomenon is given by the extraction process using a mixture of Cyanex 572 - tributyl phosphate with susceptible synergistic coefficient (S) values of 3.4646 to infinity. [ABSTRACT FROM AUTHOR]

Optimization of Gd purification in Yttrium concentrate from the process of xenotime sand by extraction using Aliquat 336 solvent has been done. The extraction process aims to separate Gd from Y and Dy. The parameters that influence the extraction process include feed acidity, feed concentration, stirring time, stirring speed, and feed phase ratio with solvent phase. To find out the results, an analysis using X-ray fluorescence was carried out. From the experimental, the best condition was obtained at 1 M feed acidity, 0.5 gram feed concentration in 25 mL, 25% solvent concentration Aliquat 336, FA:FO ratio = 1:2, 20 minutes stirring time with 200 rpm stirring speed. In this condition, the separation factor Gd-Y = 3.45 and Gd-Dy = 26.99 are obtained. [ABSTRACT FROM AUTHOR]