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The prolonged use of computers, followed by incorrect posture, could cause neck pain and excessive eye refocusing. Document holder was one of office ergonomics’ tools that could reduce neck pain and eye refocusing problems. The research aims to find out the optimum document holders’ degree of tilt. Twenty female respondents from Faculty of Industrial Technology conducted typing activity using a document holder. There were three document holder’s tilt angle levels: 15°, 30°, and 45°. The responses of this study were working speed and fatigue’s level that have lower the better characteristics. Indicators of fatigue’s level that were being used were reaction time’s difference and eyes fatigue level. Working speed and reaction time difference were analyzed by using Pearson Correlation test and Multivariate Analysis of Variance. Eye fatigue level was analyzed by using Kruskal-Wallis. The results show that the optimal document holder’s degree of tilt is 45°.

The bioactively rich soursop leaf extract can be encapsulated inside several natural coating materials. The extract of soursop leaf has been found to contain many bioactive compounds such as various phenolic compounds that are beneficial for anticancer, antidiabetic and many other health benefits. However due to the sensitive nature of the bioactive molecules, encapsulation procedure was applied to prolong the activity of the biomolecules. Capsule materials used in this experiment were obtained from natural extract of Okra mucilage, Aloe vera mucilage and Maltodextrin-WPI mixture to protect the unstable bioactive compounds. Homogenation time using ultrasonication and Core to Coating ratio was differed to observe the optimum encapsulation process. The encapsulation efficiency, release factor ability, size distribution and its correlation with bioactive stability are observed using Total Phenolic methods and Antioxidant Activity before and after encapsulation. Aloe vera gave best encapsulation efficiency (88-91%) while microcapsule made with Okra gave the best antioxidant activity (DPPH IC50 633-710ppm), and maltodextrin-WPI gave best powder recovery (yield 70-73%). Keywords: aloe mucilage, antioxidant activity, encapsulation, okra mucilage, soursop tea extract

Students’ perception in the teaching and learning process is one of the variables that should be included during the process of preparing the learning process per semester to strengthen the academic environment. By having this one, the lecturer will be able to make a plan of teaching that has been enriched by the components students need. This paper aims to give an explanation of the perception of students at the English department of IUP program, Faculty of Humanities, Universitas Diponegoro of Semarang, toward the teaching and learning process during the pandemic situation conducted online. To do the research, the researcher applied the descriptive qualitative method. The data were collected by distributing semi-closed questionnaires to the student of IUP program on the teaching and learning system they had in one semester. The supporting data, such as documents and regulations from Universitas Diponegoro regulating the system of teaching and learning are also included. The semi-open questionnaires were distributed to 25 students taking courses this semester. Based on the questionnaire distributed to the students of IUP program, the result shows that most students give a significantly positive perception on the learning process and they thought the process enriches their study.

This study aimed to determine the communication patterns formed in the Sendang Jomblang community of Gabus village in conducting Sedekah Bumi. The third communication pattern is more directed in conducting Sedekah Bumi. This research was conducted using descriptive qualitative by describing the results of observations, interviews, and documentation. The method used in this research is the qualitative approach. Based on the results of the analysis of the data, it can be concluded that the communication patterns that are formed are; (1) action communication patterns, (2) interaction communication patterns, and (3) inter-community transaction communication patterns. Groups communication identity is influenced through the personal layer, engagement layer, relational and communal, all of which form a communication identity.

Introduction: Cognitive aging involves the prominent deterioration of declarative memory. Development of therapeutic approaches to cognitive aging may improve identifying processing mechanisms underlying this memory and their neurobiological bases. Previous work identified temporal binding, the capability to associate temporally distant stimuli, as a critical process for remembering complex associations among events, i.e. declarative memory. The CA1 subfield of the hippocampus is involved in memory of temporal associations, but its function remains to be specified. Based on the discovery of time cells, which fire at successive moments in temporally structured experiences, an hypothesis was recently proposed: activity of CA1 cells would bridge the gap in memory for discontiguous events. Methods: To test this hypothesis, first, we confirmed that CA1 activity is related to successful temporal binding in memory by combining trace fear conditioning procedure at different levels of temporal binding demand (tone-shock interval length) to Fos neuroimaging. Then we demonstrated that CA1 activity is necessary during temporal gaps between the (to be-associated) stimuli for successful temporal binding by combining trace fear conditioning to an optogenetic approach. We inhibited CA1 activity specifically in or out of the trace interval during acquisition of 20 seconds trace conditioning. Results: We found that successful tone-shock binding in memory only occurs for a tone-shock interval of 20 seconds and that CA1 is the sole area in which activity is increased by successful temporal binding compared to the other learning conditions under which no temporal binding occurs. We found that successful tone-shock binding in memory requires CA1 activity during temporal gap between the tone and the shock. Conclusion: Our findings validate the "time cells" hypothesis that CA1 activity is critically needed during learning to bridge temporal gaps between discontiguous events in memory. [ABSTRACT FROM AUTHOR]

Eco-friendly synthesis of imine derivative compound from 2-hydroxy acetophenone and vanillin had been conducted by using a method of stirring (with stirrer) in a water solvent. The whole experiment began with the synthesis of imine compounds, followed by purification and characterization of the synthesis products and finally analysis on their biological and antioxidant activities. The experiments showed that imine compounds could be synthesized by a chemical reaction of 4-amino antipirin aqueous solution with 2-hydroxy acetophenone and vanillin at magnetic stirrer speed of 250 and 450 rpm, respectively, which produced product A, (E)-4-(1-(2-hydroxyphenyl) ethylideneamino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one and product B, (E)-4-(4-hydroxy-3-(vinyloxy) benzylideneamino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one. Yield percentage (%) obtained from the synthesis of product A and B were 40.68% and 19.76% respectively. Toxicity and antioxidant activity tests showed that the product B were toxic and more active as an antioxidant than product A. While the antibacterial activity test showed that both products had a response to Staphyllococcus aureus bacteria and Escherechia coli bacteria.

Guttiferron F and essential oil were isolated from extract n-hexane of Garcinia cf bancana Miq. Antioxidant activity was done by DPPH method to n-hexane, methanol, ethyl acetate, n-butanol extracts and Guttiferron F, showed activity with IC50 24.5, 22.4, 29.2, 37.6 and 25.8 µg/mL respectively. The structure elucidation of Guttiferon F based on spectroscopy data of IR, NMR of 1H and 13C. Keywords: Antioxidant, Garcinia cf bancana Miq., Essential oil and Guttiferon-F.

This article aims to compare the performance of combination of Genetic Algorithm-Simulated Annealing (GA-SA) with Particle Swarm Optimization (PSO) to solve facility layout problem. GA-SA in this article consist of two algorithms, GA-SA I and GA-SA II, with a different mutation rule. PSO uses fuzzy particle swarm concept to represent solution from each particle. Two criteria to analyze all algorithms performance are moment of movement and computational time. Experiments show that GA-SA II has the best performance in minimization both criteria

This article discusses the combination of genetic algorithm (GA) and Data Envelopment Analysis (DEA) to solve the flowshop scheduling problems with multicriteria. The criteria are makespan, total weighted tardiness, and mean flow time. DEA is used to calculate the overall value of criteria from each sequence. Relative efficiency value is employed as the fitted value in genetic algorithm, in order to have overall value that independent to a particular weight. The proposed algorithm that combines GA and DEA attain optimal solutions with relative efficiency as good as analytical solution, i.e., Mixed Integer Programming (MIP). From 30 problems generated, only one problem (3,33%) has relative efficienly less than 1. Abstract in Bahasa Indonesia: Artikel ini membahas kombinasi algoritma genetik dengan Data Envelopment Analysis (DEA) untuk pemecahan masalah penjadwalan flowshop multikriteria. Kriteria-kriteria yang digunakan, yaitu makespan, total weighted tardiness, dan mean flow time. DEA digunakan untuk menghitung nilai keseluruhan kriteria dari setiap sequence dengan menggunakan nilai efisiensi relatif sebagai fitted value dalam algoritma genetik. Hal ini ditujukan agar nilai keseluruhan dari kriteria-kriteria yang ada tidak terikat pada satu jenis bobot saja. Kombinasi dua metode ini menghasilkan suatu algoritma yang mampu menghasilkan kumpulan solusi optimal dengan nilai efisiensi relatif yang tidak kalah jika dibandingkan dengan hasil dari model Mixed Integer Programming (MIP), dimana dari 30 masalah yang dibangkitkan, hanya ada 1 masalah (3,33%) yang memiliki efisiensi relatif di bawah 1. Kata kunci: penjadwalan flowshop, algoritma genetik, Data Envelopment Analysis.

The research discusses the quality control system in producing lamp filament. Meantime, the quality control system produces ahigh level of failure, 10-17%. The result of the identification revealed that the primary coil and double coil processes have the highest failure, ± 17%, and the main cause of rejection is the unflat coil. The research covers the development of attribute control chart (p chart), before and after implementations, development of control plans and documents needed, expert system program to investigate the root cause of the failure, proportional test and final result failure. The result of the implementation of suggestion, gives a significant decrease of failure and the average of failure level of the final product is average 5.74%. Abstract in Bahasa Indonesia : Penelitian ini membahas sistem pengendalian kualitas pada pembuatan lampu filamen. Sistem pengendalian kualitas yang berjalan sekarang menghasilkan kecacatan yang tinggi, 10-17%. Identifikasi yang telah dilakukan menunjukkan bahwa proses primary coil dan double coil memiliki tingkat kecacatan terbesar ± 17% dengan penyebab utama reject adalah coil tidak rata. Penelitian yang dilakukan meliputi pembuatan dan monitoring peta kendali atribut (p chart) baik awal dan akhir hasil implementasi usulan, pembuatan control plan, dokumen-dokumen terhadap pengendalian penyebab kecacatan utama, program expert system yang digunakan untuk penelusuran penyebab kecacatan, uji proporsi dan tingkat kecacatan akhir. Hasil implementasi usulan memberikan penurunan tingkat kecacatan yang signifikan terhadap penyebab kecacatan utama dan rata-rata tingkat kecacatan produk akhir sebesar 5,74%. Kata kunci: sistem pengendalian kualitas, expert system.