Brawijaya University

In this article, we include the memory effect in the generalized Richards model (GRM), which is proposed in the form of a fractional-order GRM. The fractional-order GRM is developed by replacing the first-order derivative in the GRM with a fractional-order derivative and then taking care of model homogeneity of dimension. We consider two fractional-order differential operators: Caputo and Atangana-Baleanu in the Caputo sense (ABC). The proposed fractional order models are then implemented to fit the COVID-19 data in East Java, Indonesia from March 25 until October 31, 2020. The fitting is performed by minimizing the sum of the squared residual between the numerical solutions of each fractional-order model and the daily data of a cumulative number of COVID-19 cases. The numerical solutions of both fractional-order models are determined by the predictor-corrector method. The performance of the two fractional models is measured by two performance metrics: coefficient of determination (R 2) and root mean square error (RMSE). By considering that the order of fractional derivative as an extra degree of freedom, we perform data fitting for several orders of fractional derivative and evaluate the two performance metrics. It is observed that the fractional order model with the ABC operator generally has the best performance in calibrating and forecasting both the cumulative number of COVID-19 cases and daily new cases of COVID-19.

This study aims to analyse how internal parental migration influences school participation and work for children aged 10–15 years in Indonesia as measured by four categories, namely, (a) children attending school, (b) working children, (c) children attending school and working and (d) children who do not attend school and do not work (idle). The method used in this study is a multinomial logit model, while the data used is from the 2015 Inter-Census Population Survey (SUPAS) provided by Indonesian Central Board of Statistics (BPS). The results show that parental internal migration generally leads to a reduction in school participation rates and an increase in work participation rates among the children of migrant parents. The impact is greater when the mother migrates. However, the negative impact of parental internal migration on children’s participation in education and child labour decreases as the duration of migration increases. In addition, this study also provides some important findings regarding the important aspects that can affect child school participation and work, including the quality of parents’ work after migration, parents’ education, child’s age, family size and family welfare, including the quality of the environment where the children live.

This article investigates the performance of porous asphalt (PA) mixtures and presents the first-ever full-scale test of a PA pavement overlay applied to a bridge deck on a motorway in Thailand, thus highlighting its engineering application for enhanced safety and durability. Phase 1 of the project ‘optimized’ the amount of Tafpack Super (TPS) additive and asphalt contents through tests and finite element analyses (FEA). The optimum amount of TPS additive was found to be 12% of the total weight of AC 60/70, which, together with an asphalt content of 4.5%, achieved an air void volume of 21.8%. Compared to a conventional AC 60/70 mixture, the ‘optimized’ mixture had a lower penetration value (−30%), higher softening point (+88%) and higher viscosity (+400%), thus meeting the requirements of the Japanese guidelines for PA. FEA also investigated the effect of Wheel Tracking loads on small slabs made with the ‘optimized’ PA mixture, and the results agreed well (within a 5% accuracy) with the test results. In Phase 2, the ‘optimized’ mixture was used to build 410 m of an actual motorway pavement (including a bridge deck overlay) to demonstrate the practical application of PA in busy road infrastructure in Southeast Asia. After six years of service, such PA pavement was shown to have higher skid resistance (+25%) and permeability (+3%) over conventional AC 60/70 mixtures currently used in road construction, underscoring the significance of PA pavements at enhancing road safety and performance in harsh climate conditions typical of the region.

The potentiodynamic polarization method has investigated the corrosion behavior of zinc metal in 3.5% NaOH with a variation of bee wax popolis extract (BWPE) inhibitor, variation of immersion time, and temperature. Zinc plates were tested at 150 °C and 200 °C with immersion durations of 2, 4, and 6 hours, respectively. The variation of inhibitor concentration on corrosion rate has also been studied from 0, 200, 400, 600, 800, and 1000 ppm, followed by testing temperature variations of 25, 35, and 45°C for optimal inhibitor concentration. It is expected that this research will contribute to alternative organic corrosion inhibitors. Tafel polarization test results demonstrated that the corrosion rate of zinc metal in 3% NaOH increased with increasing test temperature and immersion time. Increasing the concentration of BWPE inhibitor from 200 ppm to 1000 ppm can reduce the corrosion rate of zinc metal from the sample without blank with optimal inhibition effectiveness obtained at a concentration of 800 ppm by 46.16%

Plain language summary Purpose: This study investigates the impact of KIC (knowledge infrastructure capability), KAC (knowledge absorption capacity), AIN (ambidextrous innovation) and SCA (sustainable competitive advantage). Methods: A survey used a saturated sample of 55 multi-raters from non-vocation private tertiary education institutions unit of analysis in Indonesia. Partial least squares structural equation modeling (PLS-SEM) is a statistical technique utilized to evaluate and test hypotheses within a particular theoretical framework. Conclusions: The study results indicate a positive and significant influence sequentially between KIC on KAC, KAC to AIN, and AIN to SCA. Knowledge management produces innovations that ultimately increase competitiveness. Implications: The results of this study support the RBV theory, which states that to be sustainable competitive, non-vocational PTS organizations must have VRIN resources and capabilities. This research also presents some practical implications for INVPTE leaders in West Java and decision-makers at the regional level (LLDikti Wilayah 4) and the national level (Kemenristekdikti/Kemendikbud Ristek). INVPTE in West Java should pay attention to KIC. Limitations: The first limitation of the research is a lack of generalization of the research results, which are only in the context of INVPTES (single sector). Second, the data of this study are cross-sectional, so future research agendas have the potential for longitudinal analysis. Third, the minimum number of samples for this research is 55 INVPTE organizations that have met the rule of thumb for PLS-SEM processing. The larger the number of samples, the greater the statistical power, affecting the hypothesis testing results. Fourth, the context of this research is only on NVPTE. The gap is open for future research with a broader context, namely, for vocational and public higher education institutions. Furthermore, the theoretical framework employed in this study does not encompass an analysis of the intricacies of the organizational environment.

Ulcerative colitis (UC) is an inflammatory disease of the large intestine characterized by ulceration and diffuse mucosal damage. Virgin coconut oil (VCO), with its anti-inflammatory properties, emerges as a potential preventive solution for UC. VCO can be an alternative because it has relatively few side effects compared to chemical drugs. This study aims to determine the effect of VCO on suppressing colonic mucosal inflammation and clinical symptoms of UC through pathway analysis. A model grounded in equations within path analysis emerges as a superior framework compared to regression for elucidating the collective impact of PPAR-γ expression, NF-κB p65 expression, the quantity of M1 and M2 macrophages, the M1/M2 macrophage ratio, as well as TNF-α, IL-6, and IL-10 levels, and the MCHI score on DAI in UC model mice. Achieving an R2y9 value of 0.998 vastly surpasses the R2 value of 0.252 attained through regression analysis. This R2y9 value denotes that the cumulative influence of the mentioned variables on DAI stands at an impressive 99.8%. Drawing from the outcomes of pathway analysis, it is evident that VCO exhibits anti-inflammatory properties in UC model mice. To advance this understanding, future investigations could focus on refining VCO into a medicinal formulation suitable for commercial consumption.

Mangrove plants are potential raw materials for a variety of food and beverage items. Mangrove leaves can be processed into is mangrove herbal teas. Eight leaf samples of Acanthus ilicifolius (AI), Avicennia marina (AM), Rhizophora apiculata (RA), Nypa fruticans (NF), Rhizophora mucronata (RM), Sonneratia caseolaris (SC), Sonneratia alba (SA), and Xylocarpus granatum (XG) from Berau Regency, Kalimantan, Indonesia were investigated for phytochemical content (TPC and TFC), antioxidant activities (ABTS, DPPH, and FRAP), and anticancer activities (HepG2 and CaCo2 cancer cell line) have been done. We compared mangrove herbal teas to commercial black tea (Camelia sinensis/CS) for all activities. The result showed that the TPC value of CS was the highest and for TFC was in XG. Moreover, the antioxidant activities on ABTS possessed similar values except for AM, which had the lowest activities; on DPPH, SC and AI showed the highest activities among others; while SC and XG had the highest activities on FRAP. SC showed the highest activities on both cancer cell lines from the anticancer activities. We conclude that mangrove herbal teas from SC leaves have the potential to be functional food with great activities as antioxidants and anticancer agents.

Musa acuminata is a major wild banana species close-relative to modern bananas. It provides important genetic materials for further banana improvement to address global threats. However, the population ecology, phenotypic variation, and conservation strategies of wild bananas in Indonesia remain poorly understood. This current study, located at Bromo Tengger Semeru National Park (BTSNP) in East Java as a showcase, revealed that wild banana M. acuminata populations were abundantly distributed in clumped patterns on open areas with high light intensities and air humidities from lowland to submontane and montane zones. The population structures were considered healthy and sustainable; dominated by juvenile and mature-vegetative, followed by suckers and a small proportion of mature-generative. The communities were found to be more abundant and had higher phenotypic richness at elevations above 1300 m asl than at lower elevations. Environmental conditions, particularly the light intensity, land slope and soil properties, are factors that contribute significantly to the ecology of wild banana populations. Based on phenotypic characterisation, it was identified as a complex variety of M. acuminata var. rutilifes, nakaii and zebrina. M. acuminata var. rutilifes mostly occupied lower elevations, while var. nakaii and/or zebrina at higher elevations. Phenotypic differentiation was significantly related to elevation as one of the geographical barriers. Based on the SWOT analysis, the suitable conservation strategy for wild banana in BTSNP is assertive or proactive. In-situ, ex-situ and on-farm conservation approaches are suggested. Bioprospecting research on wild bananas is encouraged. Due to the lack of public knowledge about the importance of wild banana conservation, awareness raising is also prioritised as a conservation action.

The COVID-19 pandemic has significantly impacted mental well-being, leading to increased stress, anxiety, and social isolation, particularly affecting students’ self-confidence and academic performance. This study aims to establish the relationship between anxiety levels and student satisfaction with distance learning in taxation during the pandemic. The study is conducted quantitatively using surveys and explicitly targets students from Brawijaya University’s Taxation Study Program in Indonesia. This program was chosen because its distinctive curriculum combines theoretical and practical tax components, making it difficult to reproduce online. The research sample was taken using purposive sampling. It reveals that anxiety, directly and indirectly, influences student satisfaction during distance learning, with higher mental pressure correlating with lower satisfaction levels. These findings suggest administrators should consider academic factors in online learning to boost satisfaction and alleviate anxiety. However, the study’s specificity to Brawijaya University’s Taxation Program warrants caution against universal application. Future research could explore additional moderating variables such as learning motivation, skills, social support, and technology readiness to understand students’ diverse learning experiences better.

Ground mustard seeds can be incorporated into a packaging film material to have a controlled release of allyl isothiocyanates (AITC). However, the properties of film material loaded with ground mustard seeds need to be evaluated, since they might influence the release of AITC from the film materials. This study aimed to assess properties, including surface morphology, spectral analysis, crystallinity, the moisture‐related, thermal and mechanical properties, of the film materials incorporated with the ground seeds and the release of antimicrobial compounds. Furthermore, the effects of relative humidity on AITC release in the headspace were investigated. The results showed that incorporating a larger quantity of ground mustard seeds resulted in the quicker release of AITC due to direct exposure to moisture, as indicated by higher concentrations observed in the headspace. Meanwhile, a smaller quantity of ground seeds added to the film maintained the thermal properties of the materials until 100 °C, resulting in significantly better moisture‐related properties and higher mechanical strength in terms of tensile strength, elastic modulus, and strain at break. However, the smallest ratio (1:5) showed no release of AITC into the packaging headspace at 75% and 100% RH. Furthermore, the relative humidity led to the release of more AITC in the headspace, which is potentially applied for high‐moisture food products. Based on the influence of relative humidity on AITC concentrations, the mechanism of AITC release from the film materials is proposed, describing the AITC diffusion from ground mustard seeds, film, and headspace.

This research investigates the role of women as a moderator variable in the relationship between governance and environmental, social, and governance (ESG) performance during the COVID-19 crisis. Using the sample of firms from five Association of Southeast Asian Nations (ASEAN) countries, the results show that the presence of women in a board structure has a positive impact on ESG performance during the normal era. However, the woman board members have not proven to strengthen the relationship between governance and ESG performance during the COVID-19 era. This could be caused by the fact that in the COVID-19 era, firms need to concentrate more on short-term profit to survive. However, we believe their presence will improve the company’s reputation and speed up the firm’s recovery during times of crisis.

The oncoprotein E6, a pivotal player in HPV-16-induced cancer, has long been the focus of extensive research. Building upon our previous study, we identified asarinin and thiazolo[3,2-a] benzimidazole-3(2H)-one-(2-fluorobenzylideno)-7,8-dimethyl (thiazolo) as potential potent anti-HPV-16 E6 oncoprotein agents. Utilizing the UniProt-derived E6 sequence, we employed I-TASSER to model the protein's three-dimensional structure. Subsequent molecular docking via AutoDock Vina, coupled with a 1,000 ps dynamic analysis under physiological parameters, revealed that both asarinin and thiazolo have a high chance of forming stable protein-ligand complexes with HPV-16 E6, displaying distinct molecular dynamic properties. Thiazolo exhibited superior stability in simulation, evident in ligand conformation and movement graphs, while asarinin excelled in terms of contact residues. Furthermore, SASA, hydrogen bond graphs, and the DCCM graph collectively underscore the comparable potential of both drugs as robust inhibitors of the HPV-16 E6 oncoprotein.

The rapid social change in the world through global economic turmoil, social inequality, and degradation of the natural context triggered an increase in criticism of the marketing approach oriented towards the dimension of profit alone. The concept of modern marketing requires rebranding with sustainability issues, namely the sustainable marketing model. Marketers must present to consumers an active and responsible management attitude and openness and honesty in market communication. This study aims to investigate the influence of the application of sustainable marketing on purchasing decisions in zero waste shops, where purchase intention is a mediator. The dimensions of sustainable marketing include customer solution, customer cost, communication, and convenience. Quantitative research was undertaken by distributing survey questionnaires via google forms online. A total of 193 respondents were obtained from distributing questionnaires in Jakarta. The data was analyzed using Structural Equation Modelling-Partial Least Square (SEM-PLS). The analyses have proven that sustainable marketing positively affects purchase intention and purchase decisions. Purchase intention has a positive effect on purchase decision dan has functioned effectively as a mediator between sustainable marketing and purchase decision. This study contributes to a long-term-oriented marketing strategy by looking at the dynamics of healthy lifestyle changes that must be done quickly.

Recently, automatic question generation (AQG) has been researched extensively for educational purposes. Existing approaches generally lack relevant information on the authentic context and problem diversity with various difficulty levels, so we proposed a new AQG system for generating contextualized and personalized mathematic word problems (MWP) in authentic contexts using the Generative Pre-trained Transformers (GPT). Our proposed system comprises (1) authentic contextual information acquisition through image recognition by TensorFlow and augmented reality (AR) measurement by AR Core, (2) a personalized mechanism based on instructional prompts to generate three different difficulty levels for learners' different needs, and (3) MWP generation through GPT with authentic contextual information and per-sonalized needs. We conducted a quasi-experiment with the participation of 52 students to evaluate the effectiveness of the proposed system on geometry learning performance. Further, the learning behaviors were analyzed in the aspects of authentic context, mathematics, and reflective behavior. The findings showed better results in geometry learning performances from students who learned with contextualized and personalized MWPs than those who were taught without contextualization and personalization on MWPs. Moreover, it was found that student's ability to comprehend the practical situation or scenario presented in a problem (problem context understanding) and students' ability to recognize relevant information from the problem context (identifying contextual information) significantly improved their learning performance. Moreover, students' ability to apply math concepts and solve medium-level MWP also contributes to the improvement of learning performance. Meanwhile, learners showed positive perceptions toward the proposed system in facilitating geometry learning. Therefore, it is useful to promote an authentic context setting for mathematical problem-solving.

Nutrient management in coffee-based agroforestry systems plays a critical role in soil nitrogen (N) cycling, but has not been well documented. The objective of this study was to evaluate the effect of coffee canopy management and fertilization on soil N dynamics. This study used a randomized complete block design (2 × 3 × 2) with four replications. There were three factors: 1) coffee canopy management (T1: Pruned, T2: Unpruned), 2) fertilizer type (O: Organic, I: Inorganic; M: 50% Organic + 50% Inorganic), and 3) fertilizer dose (D1: low, D2: medium, D3: high). Soil N dynamic indicators (i.e., total N, ammonium (NH4⁺), nitrate (NO3⁻), net N-NH4⁺, net N-NO3⁻, soil microbial biomass N) were measured at two soil sampling depths (0–20 cm and 20–40 cm). Results showed that pruning increased soil total N and microbial biomass N (MBN) by 10–56% relative to unpruned coffee trees. In contrast, the unpruned coffee canopy had 15–345% higher NH4⁺, NO3⁻, net N-NH4⁺, net N-NO3⁻, and microbial biomass N concentration than pruned coffee. Mixed fertilizer application increased NO3⁻ and net N-NH4⁺ accumulation by 5–15% relative to inorganic and organic fertilizers. In addition, medium to high dose fertilization led to a 19–86% higher net N-NO3⁻ concentration and microbial biomass N as compared to low dose fertilization. The treatment of no pruning and mixed fertilizer at low to medium doses was the optimal management strategy to maintain soil available N, while pruning combined with organic fertilizer has the potential to improve soil total N and MBN.