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Authentic context is a physical environment reflecting the knowledge application in the real world. In this study, we developed a tablet-based application, Ubiquitous Fraction (U-Fraction), to help fractions learning with authentic contextual support. Three topics were designed to learn fractions concept, fractions simplification, and fractions addition/subtraction. The learning achievement was evaluated by three variables: understanding fraction and fraction representation to evaluate fractions concept and fractions simplification, and problem solving to evaluate the three topics. This study used two groups of experimental research. The experimental group (EG) learned fractions using U-Fraction in authentic contexts, while the control group (CG) learned fractions using the traditional teaching method and paper-based assignment. The results showed that EG significantly outperformed CG. Furthermore, it was found that learning behaviors of EG had significant correlation among quantity of assignment, annotations of assignment, and post-test. Two assessment mechanisms, peer and teacher assessments using scaffoldings based on multiple representations (i.e., linguistic, logic mathematics, and visual representation), were employed to help assessment and improve the assessment results. It was found that the scaffoldings can help both peer and teacher assessments, which significantly correlated with post-test. Therefore, multiple representations and scaffoldings were helpful to improve students' learning and peer assessment. Students also perceived positively toward using U-Fraction in terms of usefulness, ease of use, ease of learning, and satisfaction of the usability questionnaire. These imply that fraction learning should be designed in a way that students can apply their knowledge in authentic contexts by taking pictures and making multiple representations.

Penelitian ini bertujuan untuk menggali aspek kontekstual yang memengaruhi implementasi program CSV. Dengan pemahaman yang dalam mengenai CSV dan elaborasi terhadap konteksnya, penelitian kualitatif eksploratif dengan desain studi kasus ini berusaha mendalami program CSV Kamojang Desa Digital yang dijalankan oleh PT Pertamina Geothermal Energi (PGE) Area Kamojang dari perspektif perencana dan pelaksana program. Hasil penelitian menunjukkan bahwa meskipun CSV merupakan mandat PT Pertamina (Persero), implementasinya mengalami translasi sehingga menghadirkan konsepsi yang memiliki distingsi dengan gagasan aslinya. Dari tiga subprogram yang diteliti, hanya Geotato dan Rangers App yang dapat dikategorikan sebagai CSV dengan model redefinisi rantai nilai perusahaan. Terdapat tujuh konteks yang berhasil diabstraksi, yakni kapasitas perusahaan dalam berjejaring, kepatuhan terhadap regulasi, budaya CSV perusahaan, kapabilitas menciptakan inovasi, dinamika produktivitas komoditas lokal, kendala kompetensi, dan keberlanjutan ekologis. Ketujuh konteks tersebut terkait dengan konteks pembangunan desa di Indonesia yang mengalami disparitas dalam pelayanan publik dan limitasi akses terhadap teknologi modern. Kata kunci: konteks CSV, disparitas pelayanan publik, limitasi akses teknologi Abstract This study aims to explore contextual aspects that affect the implementation of the CSV program. Conceptualizing of CSV and its context, this exploratory qualitative research with a case study design has investigated the Kamojang Desa Digital CSV program run by PT PGE Area Kamojang from the planners’ and implementers’ perspectives. The results show that, although CSV is a mandate from PT Pertamina (Persero), its implementation is examined through translation that presents distinctive conception of the original idea. Of the three subprograms, only Geotato and Rangers App can be categorized as CSV with redefinition of the value chain model. Seven contexts have been abstracted: company capacity in networking, regulatory compliance, corporate CSV culture, capability to create innovation, dynamics of local commodity productivity, competency constraints, and ecological sustainability. Those are related to the context of village development in Indonesia, which is experiencing disparities in public services and limited access to modern technology. Keywords: CSV context, public service disparities, technological access limitations

Concrete is a material that is often used in construction in Indonesia. Concrete has the disadvantage that it tends to form cracks. The cracks that form start from small cracks and then enlarge, causing a decrease in quality. Self-healing concrete is a type of concrete that could repair itself with the help of healing agents in the form of bacteria. There are several methods of mixing bacteria into concrete, one of which is by mixing bacteria directly or using a shell which is often called encapsulation. The purpose of this study was to analyze the behavior of the addition of Bacillus Megaterium bacterial encapsulation in terms of compressive strength of concrete with encapsulation proportions of 0%, 2% and 4% by volume weight and using alginate-based shells. The samples used were 15 x 30 cm cylindrical specimens. These specimens were then tested after 7 days and 28 days. Based on test result, it was found that the highest compressive strength was obtained when 2% alginate capsules were added on day 7 and day 28, namely 25.6 MPa and 32.2 MPa. Concrete begun to heal after 2 weeks of curing based on visual observation.

Cracks in concrete beams can significantly affect the performance of reinforced structures. To repair cracks in concrete, Traditional crack repair methods typically involve epoxy injection, but studies have suggested that epoxy may not fully restore the original strength. Therefore, concrete structure repair requires the development of new and more efficient materials. This study focuses on investigating the potential of Bacillus megaterium, a bacterium known for its self-healing properties in concrete. This bacterium has the capability to precipitate minerals like calcium carbonate, which can fill the cracks and increase the strength of concrete. Testing is carried out on reinforced concrete beams with existing cracks, sized at 100 mm x 100 mm x 500 mm. The specimens are divided into two groups, one repaired with epoxy injection and the other with bacterial injection, with varying additions of 10% and 15%. The research results show that the injection process with the addition of 15% bacteria is able to restore approximately 99.72% of the initial strength of the concrete beams. The results of this research contribute to the development of improved repair techniques that can restore the flexural strength of cracked concrete beams and extend the service life of concrete structures.

Most food packaging consists of plastic which is difficult to degrade. One strategy for addressing this issue is the development of biodegradable polymers from cassava starch, a known of raw material easily produced at low cost and biologically to degrade, hence becoming a low-cost for edible film production. The edible film was prepared by gelatinization method using cassava starch and glycerol as plasticizers. The study was subjected to determine the optimum drying process for cassava starch-based edible film based on the drying condition process with two independent variables: drying temperature (40, 50, and 60°C) and drying time (4, 5, and 6 h) on the mechanical properties. The response surface methodology approach with a central composite design was used for optimization. The experimental data for the optimum drying condition were analyzed to obtain the optimized variables using plots and contours. The optimized edible film occurred at a drying temperature of 63.28 °C and drying time of 3.58 h resulting in a tensile strength of 6640.24 Pa, elongation at break of 1.051%, and water solubility of 55.575%. The study concluded that the optimized drying condition process significantly affected the tensile strength, elongation at break, and water solubility.

The waste problem has become a disturbing problem in Prabumulih City. In Prabumulih City, there is over capacity at the Final Disposal Site. This is because the volume of waste coming in is very large and has not been managed well. The impact is very negative from an environmental, economic and social perspective. CSR PT Pertamina EP Prabumulih Field is participating in overcoming this through Program Pusat Daur Ulang Sampah Mandiri dan Berkelanjutan (PADU PADAN) as a community development (comdev) program. This research method is in the form of a qualitative field study or field research. The data collection techniques were carried out using observation with active participation, in-depth interviews, documentation and focus group discussions. The research results show: Program Pusat Daur Ulang Sampah Mandiri dan Berkelanjutan (PADU PADAN) program is an educational activity for sorting and processing organic and anorganic waste into marketable products. This program is under the auspices of the CSR of PT Pertamina EP Prabumulih Field in South Sumatra. Program Pusat Daur Ulang Sampah Mandiri dan Berkelanjutan (PADU PADAN) consists of two main programs, namely: 1) Perempuan Berdaya Bersama Kelola Sampah (MUDA BERSAMA), 2) Rumah Inovasi Daur Ulang Sampah Residu Anorganik (RINDU RESIK). The Muda Bersama Program specifically processes organic waste, while the Rindu Resik Program is a process for handling anorganic waste. These two programs have a positive impact on society both from an economic, social and environmental perspective. [ABSTRACT FROM AUTHOR]

The central concern surrounding chemical pesticide application is its potential adverse effects on non‐target organisms. For fungal pathogens, the search for specific targets has been complicated by the similarities in pathways shared between these pathogens and humans. We present a comprehensive strategy, integrating comparative omics and bioinformatics, to pinpoint precise targets for fungicides effective against the fungal pathogen Magnaporthe oryzae, responsible for rice blast disease. Our approach involves subtractive metabolic pathways, homology screening and target prioritization. Through subtractive metabolic analysis, we identified three unique M. oryzae pathways, distinct from human and rice. Nonredundant protein sequences were subsequently subjected to BLASTP screening against human and rice, as well as other databases from diverse organisms. Target subcellular localization was predicted using eight tools, including artificial intelligence and a deep‐learning method. A comprehensive examination of biological processes was conducted, including gene expression, protein–protein interactions, network enrichment, broad‐spectrum activity and physicochemical analysis. Glutamate 5‐kinase emerged as the prime candidate for targeted fungicide development, promising progress in precision‐oriented solutions. [ABSTRACT FROM AUTHOR]

This research endeavors to develop a geopolymer mortar synthesized from eggshell powder and ground granulated blast-furnace slag, utilizing the Taguchi L25 optimization technique to refine the synthesis process across molarity (A), precursor ratio (B) and curing duration (C). Analyzed at five distinct levels across 25 experimental setups, denoted as A1B1C1 through A5B5C5, these variables were rigorously tested. Compressive-strength measurement was employed as a criterion to assess the performance of three samples from each setup, alongside setting-time evaluation to ascertain the geopolymer concrete's workability. Optimal results were observed with a 60% eggshell to 40% slag ratio (A5B1C5), yielding the highest average compressive strength of 49.5 MPa after a curing period of 56 days. Conversely, a mix comprising 100% eggshell (A2B5C1) manifested the lowest compressive strength of 5 MPa at a 3-day curing period. Taguchi's signal-to-noise ratio analysis pinpointed the precursor ratio as a crucial determinant of compressive strength. Additionally, setting-time investigations revealed A5B1C5 as exhibiting the most advantageous initial and final setting times of 15 minutes and 30 minutes, respectively, compared to the protracted durations of 240 minutes and 540 minutes for A2B5C1. Through comprehensive chemical, micro-structural and mineralogical characterizations via X-ray fluorescence, Scanning Electron Microscopy (SEM) and X-ray diffraction, it was found that an increased proportion of ground granulated blastfurnace slag relative to eggshell enhances surface smoothness and density, indicative of successful polymerization. This was further corroborated by X-ray diffraction, which confirmed the formation of sodium alumina-silicate hydrate, calcium aluminum silicate hydrate and calcium silicate hydrate gels. Consequently, the study substantiates the potential of employing eggshell powder and ground granulated blast-furnace slag in the sustainable fabrication of geopolymers from waste materials. [ABSTRACT FROM AUTHOR]