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Activated carbon from agro-industrial waste, namely tea twigs derived from the processing of Camellia Sinensis branches, using a potassium hydroxide activator for CO2 adsorption has been conducted in this study. Various carbonization temperatures (4000C and 5000C) and heating times of 1 h and 3 h were used in this study. The concentration of potassium hydroxide (40 % and 60 %) and the ratios of activator solutions to carbon precursor made from pyrolysis of tea twigs (2:1 and 4:1) were varied for the chemical activation process. The effectiveness results of the obtained activated carbon were characterized through using Brunauer-Emmett-Teller analyzer and Temperature Programme Desorption-CO2 to determine the surface area and capacity maximum of CO2 adsorption. The optimum condition for the synthesis of activated carbon that produces high surface area was obtained at sample CCS 400/1 A2B1 where biochar carbonized at temperature of 400 °C kept for 1 h with a ratio of activator solution and precursor 4:1 using KOH concentration of 40 %. The highest surface area was obtained 1403 m2 g−1 with pore volume 0.9 m2 g−1 and pore size 1.11 nm and proved the presence of microporous areas in produced activated carbon. The maximum CO2 adsorption capacity obtained in this study was 5.1573 mmol g−1. This result could be related to the higher amount of microporous present in the activated carbon that facilitates the access of CO2 to the active sites at the pores of activated carbon.

Improving the quality of syngas from fine coal waste using the sorption-enhanced gasification process is a novel technology in the production of H2. The effect of CaO on CO2 absorption and H2 increase in the steam fine coal gasification process was determined in a fixed bed gasifier. The steam gasification process took place at 650 °C using bentonite and CaO as catalysts and absorbents. Steam increased the H2 concentration in the syngas to 58 vol%. In-situ CO2 absorption is more effective with the addition of CaO. The maximum percentage of CO2 was absorbed when the Ca/C ratio 2 was 78.33 %. The H2 content in the syngas after the CO2 was absorbed increased rapidly to 75.80 vol% at a Ca-to-carbon-mole ratio (Ca/C) of 1.5 and a steam-to-feedstock ratio (S/F) of 1.5. CaO did not produce significant results for low heating value (LHV) or cold gas efficiency (CGE), with results of 12 MJ/Nm3 and 44.53 %. The dominant water gas shift reaction due to the influence of steam and CaO increased H2/CO up to 9.11, which made the syngas from this work suitable for Fischer–Tropsch synthesis.

Vasconcellea pubescens A. DC., commonly referred to as mountain papaya, belongs to the Caricaceae family and is native to the Andean highlands. In Indonesia, mountain papaya can be found on the Dieng Plateau and has become one of the typical processed products from the Dieng area. The aim of the study is to explore the diversity and phenetic relationship of mountain papaya from the Dieng Plateau based on morphological markers. This study is important to provide information in guiding future conservation efforts. 18 samples were collected from three areas with different altitudes in the Dieng Plateau. In addition, it proved valuable results by elucidating patterns of variation, enabling the identification of distinct groups. A total of 18 samples were collected from three areas with varying altitudes in the Dieng Plateau. Morphological analysis used 22 characters with The Clustering Analysis Method, Principal Component Analysis (PCA), and Diversity Analysis using Multivariate Statistical Package (MVSP) software version 3.1A. The results of cluster analysis showed that mountain papaya accessions were grouped into two main clusters and five sub-clusters. Cluster grouping based on sex distribution characters, flower stalk length, and inflorescence density; there is no grouping based on geographical location or altitude. The Shannon's Index Value (H') for mountain papaya shows moderate phenetic diversity. This suggests that the mountain papaya community remains stable within its substrate and its environmental parameters.

The matter of transparency regarding information and data emerges as a pivotal concern in the context of mitigating the COVID-19 epidemic in Indonesia. The regulation of public information transparency in Indonesia is stipulated in Law Number 14 of 2008, which ensures the disclosure of public information. The objective of this study is to conduct a comprehensive examination of the extent to which the Government of Indonesia adheres to the principles outlined in its legislation with regard to the implementation of transparency throughout the pandemic. The approach employed to assess the degree of adherence is normative-empirical analysis. The findings of this research analysis indicate a significant lack of transparency in the public dissemination of COVID-19 information and data in Indonesia. This lack of transparency is inconsistent with the provisions outlined in Law No. 14 of 2008, which governs the publication of public information in the country. The act of downplaying COVID-19 through the dissemination of information, along with the government's decision to withhold comprehensive data, and the prevailing skepticism toward scientific research might be characterized as efforts to impede citizens' access to precise knowledge.

Abstract Background Growing evidence implicates a pro-thrombotic state, caused by ADAMTS13 deficiency, in sepsis-associated organ dysfunction, but pediatric data is limited. Our purpose was to evaluate association of ADAMTS13 with prognosis of pediatric sepsis. Results This was prospective observational study, conducted on 70 children with sepsis and 18 healthy controls. Patients were classified upon Pediatric Intensive Care Unit (PICU) admission into sepsis, severe sepsis, and septic shock groups. Serum ADAMTS13 was measured within 24 h of admission. The primary outcome was all-cause PICU mortality. ADAMTS13 was lower among patients than controls [median and interquartile range (IQR): 1.30 (0.88–3.13ng/mL) vs. 6.00 (5.55–6.50 ng/mL); p

The Dieng Plateau is an area used to cultivate Mountain Papaya (Vasconcellea pubescens A.DC.) as a food commodity in Indonesia. Research on diversity and relationships is vital as a first step in Mountain Papaya conservation in the Dieng Plateau. The study aims to determine the genetic diversity and relationship between Mountain Papaya accessions using Internal Transcribed Spacer (ITS) rDNA sequences. Fourteen accessions of Mountain Papaya with different sex distributions and altitudes are amplified using ITS1 and ITS4 primers. The genetic diversity is analyzed using the DnaSP 5.10.1 program. The Maximum Likelihood (ML) approach in MEGA 11 is utilized for assessing phylogenetic tree data based on ITS-rDNA regional sequences. With high haplotype diversity (Hd) values of 1.000 ± 0.027 and high nucleotide diversity (π) values of 0.09674 ± 0.00978, Mountain Papaya exhibits a high level of genetic diversity. Three main clades were identified in the phylogram tree based on the 14 ITS-rDNA sequences of Mountain Papaya. The results of this diversity data can support breeding programs intended to boost Mountain Papaya variety production.

The no free lunch theory states that no specific heuristic method can effectively solve all problems. This theory has created opportunities for researchers to improve existing heuristic methods or even discover new approaches. One algorithm that has gained considerable attention from researchers is the Symbiotic Organism Search (SOS) algorithm. Its appeal lies in its simplicity and minimal parameter requirements, making it applicable to various problem domains. However, the SOS algorithm also has its limitations. This study focuses on the enhancement of SOS by introducing a modified random weight (MRW) method during the parasitism phase, resulting in the Improved SOS (I-SOS) algorithm. The effectiveness of this algorithm is tested in solving unconstrained problems using 26 benchmark functions and compared to several existing heuristic methods in the literature. The simulation results show that I-SOS outperforms basic SOS as well as several other algorithms.

Disposal of dye wastewater can induce detrimental consequences for human health and the environment. The study aims to synthesize composites consisting of core-shell Fe3O4/SiO2/TiO2 modified with Ag. The composites comprise a Fe3O4 core, a SiO2 interlayer, and a TiO2 shell, with Ag being mobilized on the surface of the core and shell structures. Fe3O4/SiO2/TiO2@Ag composite was employed in the photocatalytic degradation of Congo red dye and antibacterial activity test. The degradation was facilitated by visible light irradiation while considering different factors such as pH solution, the photocatalyst dosage, and the dye's initial concentration. The composite was characterized using X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning Electron Microscopy-Electron Dispersive X-ray Spectroscopy (SEM-EDS), Vibrating Sample Magnetometer (VSM), and UV-Vis Diffuse Reflectance Spectroscopy (UV-Vis DRS). The findings indicated that the composite exhibited strong magnetic, measuring 49.4 emu/g, with a band gap of 2.92 eV. The composite showed commendable catalytic properties, with degradation efficiency of 96.52% for Congo red dye under conditions: a pH solution of 4, a dosage of 0.5 g/L, and a dye concentration of 10 mg/L at 100 min of irradiation. The photocatalytic degradation kinetic is align with pseudo-first-order reactions. The composite also exhibits remarkable stability and efficiency with 4.83% decline in degradation efficiency after five cycles. Fe3O4/SiO2/TiO2@Ag composite exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus with a Minimum Inhibitory Concentration (MIC) value of 250 mg/L. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Currently the detection of learning styles from the external aspect has not produced optimal results. This research tries to solve the problem by using an internal approach. The internal approach is one that derives from the personality of the learner. One of the personality traits that each learner possesses is prior knowledge. This research starts with the prior knowledge generation process using the Latent Semantic Indexing (LSI) method. LSI is a technique using Singular Value Decomposition (SVD) to find meaning in a sentence. LSI works to generate the prior knowledge of each learner. After the prior knowledge is raised, then one can predict learning style using the artificial neural network (ANN) method. The results of this study are more accurate than the results of detection conducted with an external approach.

Research on the study of producing rich beta carotene natural fibers beverage has been done by completely randomized design (CRD) with two replicates. The first factor was the ratio of water spinach stem and melinjo seed skin (S1 = 100:0, S2 = 75:25, S3 = 50:50, S4 = 25:75, S5 = 0:100). The second factor was the addition of carrots juice (W1= 30%, W2= 40%, and W3 = 50%). The parameters observed were fiber content, β-carotene content, water absorption index, oil absorption index, hedonic value of color, flavor and aroma. The statistical analysis was showed that the ratio of water spinach stem and melinjo seed skin provide highly significant effect (P ≤ 0.05) on fiber content, beta carotene content, water absorption index, oil absorption index, hedonic of flavor and aroma as well as had no significant effect (P 0.05) to hedonic of color. The addition of carrot juice provides highly significant effect (P ≤ 0.05) on fiber content, beta-carotene content, water absorption index, oil absorption index, hedonic of aroma, color and flavor.

This study aims to determine the effect of the substitution of tofu flour and corn flour by the addition of sodium bicarbonate in a completely randomized design with two replicates. The first factor is the substitution of tofu flour: corn flour (S) are: S1=100:0, S2=25:75, S3=50:50, S4=75:25, and S5=0:100. The second factor is the effect of adding sodium bicarbonate (P), which consists of three levels, namely: P1=0.00 %, P2=0.20 %, and P3=0.30 %. The observed parameters: protein content, water content, fat content, ash content, and organoleptic texture, color, and flavor. The statistical analysis showed that the substitution of tofu flour: with corn flour provides a highly significant effect (P0.05) on the protein content, water content, fat content, ash content, organoleptic color, flavor, and texture. The effect adding sodium bicarbonate provides a highly significant effect (P0.05) on the protein content, moisture content, fat content, ash content, and organoleptic texture and no significant effect on organoleptic taste and color.

NiFe2O4/SiO2/NiO magnetic was successfully synthesized using NiFe2O4, SiO2, and NiO as the core, interlayer, and shell, respectively. NiFe2O4/SiO2/NiO under UV light irradiation was used for photocatalytic degradation of methyl orange dye with different pH, catalyst dose, and initial dye concentration. This composite was characterized by X-ray Diffraction (XRD), Fourier Transform Infra-Red (FTIR), Scanning Electron Microscopy-Electron Dispersive X-ray Spectroscopy (SEM-EDs), Vibrating Sample Magnetometer (VSM), UV-Vis Diffuse Reflectance Spectroscopy (UV-Vis DRS), and Point of Zero Charge (pHpzc). The results showed that the composite is a superparamagnetic material with a saturation magnetization value of 44.13 emu/g. It also has a band gap of 2.67 eV with a pHpzc of 6.33. The optimum conditions for photocatalytic degradation were at pH of 4; 0.50 g/L catalyst dose, and 10 mg/L initial concentration. NiFe2O4/SiO2/NiO degradation efficiency to methyl orange dye was 95.76%. The photocatalytic degradation in different concentrations follows the pseudo-first-order, where the greater the concentration, the smaller the constant rate (k). After five cycles of repeated usage, NiFe2O4/SiO2/NiO has good catalytic performance as well as efficient and favourable of a recyclable photocatalyst. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Case Based Learning (CBL) is learning that is oriented towards effective and interesting problem solving, discussions of specific situations and examples of real events in the business world. The object of the case used is an effort to preserve the environment that affects the business world from an economic, social, political and legal perspective. The activity was carried out at Sungai Karang Mumus School (SKM School), which is located on Jalan Muang Ilir, Betapus Village, Samarinda. This study aims to analyze the effect of the application of CBL on the motivation of student learning outcomes. The study used a pre-post-test approach. The total population is 25 students of Master of Management, University of Muhammadiyah East Kalimantan who are members of the environmental management class and use the total sampling technique. Non-parametric statistics, namely the pairing test of the Paired Sample t-test with the Wilcoxon test used in data processing. The results showed that there was a significant difference in student motivation and learning outcomes before applying case-based learning methods and before case-based learning was applied to environmental management courses. Students who are looking to study will have good learning outcomes. Students and then get used to think critically and use prior knowledge in problem solving. This has triggered educators and institutions to apply case-based learning methods as innovative learning.

Research on motivation of students in speaking English on extracurricular activity has been really conducted but students are still afraid of speaking English.. This manuscript is a research result dealing with motivation of English Education students in Department of Language and Art Education at Faculty of Teacher Training and Education, Tadulako University in speaking English on extracurricular activity. English speaking skill should be developed on extracurricular activity to make ideal atmosphere, but that activity has not been effective yet on all study programs except English Education at that faculty, so that the students have not been able to speak English yet. This research aims at identifying what motivates the university students and how their intention is. Its target is they taste different academic athmosphere to have English skill to interact with English speakers. Respondents of the research were 25 English education students. Its data were collected through Identification (as a procedure) by using Questionnaire (as an instrument) then analysed by using Descriptive Method. The university students join it to be able to communicate in English and get certificate. Those are extrinsic moivation and intrinsic one. Most of them were selfmotivated, so their intrinsic motivations were greater than their extrinsic one. Motivation by themselves or selfmotivator is the greatest. This implies to support decision making in developing English speaking skill of university students. They hopefully carry out and join extracurricular activities to practice their English orally for having English speaking skill proficiently.