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Full-Text Articles in Physical Sciences and Mathematics

Can Corporate Sustainability Performance (Csp) Overcome Indonesia's Corporate Debt Problems?, Johnson Ferry Febrian, Nora Sri Hendriyeni Jun 2024

Can Corporate Sustainability Performance (Csp) Overcome Indonesia's Corporate Debt Problems?, Johnson Ferry Febrian, Nora Sri Hendriyeni

Jurnal Akuntansi dan Keuangan Indonesia

Based on IMF publications (2022), Indonesian companies have a risky debt level that may cause bankruptcy, so companies are required to make leverage adjustments to return the debt to its optimal level. In recent years, corporate sustainability performance (CSP) practices have been proven to improve performance and overcome financial problems such as debt by integrating sustainability aspects into business processes. Based on stakeholder theory and trade-off theory, this study aims to examine the effect of CSP on leverage adjustment and the role of competitive advantage, equity mispricing, profitability, and firm size in moderating this relationship. This study used a sample …

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Spatial Durbin Model On The Utilization Of Delivery At Health Facilities: A 2017 Indonesian Demographic And Health Survey Analysis, Indah Sri Wahyuni, Ira Gustina, Martya Rahmaniati Makful, Tris Eryando May 2024

Spatial Durbin Model On The Utilization Of Delivery At Health Facilities: A 2017 Indonesian Demographic And Health Survey Analysis, Indah Sri Wahyuni, Ira Gustina, Martya Rahmaniati Makful, Tris Eryando

Kesmas

The utilization of delivery at health facilities is a major intervention in reducing 16 to 33% of deaths. This study aimed to determine the model of utilization of delivery at health facilities in Indonesia in 2017 and its influential factors. This study used secondary data from the 2017 Indonesian Demographic and Health Survey using a Spatial Durbin Model (SDM) approach. The population was mothers aged 15 – 49 years, spread across 34 provinces of Indonesia, and had 15,321 samples. The results showed that the Moran’s I value was positive (0.146) and significant at p-value = 0.007, indicating clustered regions with …

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Mapping For Tracking Sexually Transmitted Infections By Subdistricts In Surabaya, Indonesia, Destri Susilaningrum, Brodjol Sutijo Suprih Ulama, Fausania Hibatullah, Diandra Soja Anjani May 2024

Mapping For Tracking Sexually Transmitted Infections By Subdistricts In Surabaya, Indonesia, Destri Susilaningrum, Brodjol Sutijo Suprih Ulama, Fausania Hibatullah, Diandra Soja Anjani

Kesmas

The 2014 shutdown localization of prostitution in Surabaya City, East Java Province, Indonesia, has given rise to an illegal prostitution industry, resulting in the spread of uncontrolled sexually transmitted infections (STIs). Mapping needs to be done to track the spread of the disease. This study used secondary data on STIs in 2020 from the Surabaya City Health Office. By using biplot analysis, this study sought to offer a detailed understanding of the distribution and dynamics of STI cases in different parts of Surabaya. The early-stage syphilis was found in Tegalsari and Krembangan Subdistricts; then, gonorrheal urethritis was found in Tandes, …

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Effects Of Ti Addition On The Characteristics Of Al-10zn-6mg-2si/Zro2 Composites Produced By Squeeze Casting, Qesha Diva Prameshvara, Pipin Indah Lestari, Bondan Tiara Sofyan May 2024

Effects Of Ti Addition On The Characteristics Of Al-10zn-6mg-2si/Zro2 Composites Produced By Squeeze Casting, Qesha Diva Prameshvara, Pipin Indah Lestari, Bondan Tiara Sofyan

Journal of Materials Exploration and Findings

Metal matrix composite (MMC) with 7xxx aluminum matrix is potential for ballistic applications due to the combination of strength, toughness, and light weight. Previous study successfully produced aluminum-based composites with SiC particles which were able to stop type III bullet, however cracks remained on back of the plate. Therefore, in this research, SiC was replaced by zirconia (ZrO2) due to its high fracture toughness. Ti-B grain refiner was added to further improve toughness through grain boundary strengthening mechanism. This research developed 5 vol.% ZrO2 strengthened Al-10Zn-6Mg-2Si composite with addition of Al-5Ti-1B grain refiner produced through squeeze casting …

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Integration Of The Ashby Technique And Pahl-Beitz Quantitative Ranking For Railway Axle Material Selection, Helya Chafshoh Nafisah, Jaka Fajar Fatriansyah, Siti Norasmah Surip May 2024

Integration Of The Ashby Technique And Pahl-Beitz Quantitative Ranking For Railway Axle Material Selection, Helya Chafshoh Nafisah, Jaka Fajar Fatriansyah, Siti Norasmah Surip

Journal of Materials Exploration and Findings

Railway axle serves as a vital connection between the train's wheels and its body. However, cyclic loading and high speed can induce fatigue in railway axle, which potentially leads to damage human safety. Therefore, it is important to find materials that have good mechanical properties with the lowest weight and cost. In this paper, a comprehensive method using Ashby chart has been performed to select candidate materials of railway axle. The methods begin with analyzing function by determining the problem, objective function, and constraints. After that, the results obtained are ranked using Pahl and Beitz quantitative weighting method. The results …

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Analysis Of The Effect Of Different Surface Preparation Methods On Corrosion Resistance And Adhesion Strength Of Astm A36 Steel Substrate With Surface Tolerant Epoxy Paint As Coating Material, Irwan Wijaya Santoso, Daffa Aqila, Rini Riastuti, Rizal Tresna Ramadhani May 2024

Analysis Of The Effect Of Different Surface Preparation Methods On Corrosion Resistance And Adhesion Strength Of Astm A36 Steel Substrate With Surface Tolerant Epoxy Paint As Coating Material, Irwan Wijaya Santoso, Daffa Aqila, Rini Riastuti, Rizal Tresna Ramadhani

Journal of Materials Exploration and Findings

In the industrial world, to extend the service life of materials, protection methods are carried out to slow down the material's corrosion rate. The protection method that is often used is the coating method. The coating method is a protection method by coating the substrate material using a coating material to prevent contact between the substrate material and the environment. In this research, the substrate material used is ASTM A36 steel and the coating material used is Surface Tolerant Epoxy paint. The independent variable used in this study lies in the surface preparation method which consists of: solvent cleaning, hand …

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Thermal Performance Investigation Of Thermoelectric Cooling System With Various Hot-Side Cooling Methods, Bowo Y. Prasetyo, Parisya P. Rosulindo, Fujen Wang Apr 2024

Thermal Performance Investigation Of Thermoelectric Cooling System With Various Hot-Side Cooling Methods, Bowo Y. Prasetyo, Parisya P. Rosulindo, Fujen Wang

Makara Journal of Technology

Thermoelectric devices have been widely used in various applications, including cooling and power generation. The potential application of thermoelectric cooling systems has been studied. However, these systems still face challenges in achieving optimal performance compared with other cooling systems. Several factors, including the hot-side cooling method, influence the performance of thermoelectric systems. This study aimed to investigate the effects of different hot-side cooling methods on the thermoelectric performance and thermal behavior of thermoelectric cooling systems. The testing methods involved the combination of the thermoelectric module with five hot-side heat exchangers, including a square heatsink, a round heatsink, a two-pipe heat …

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Accurate Estimation Of Ethanol Content In Fruit Juices Using Cielab Color Space And Chemometrics Via Smartphone-Based Digital Image Colorimetry, Chairul Ichsan, Yasir Amrulloh, Desti Erviana Mar 2024

Accurate Estimation Of Ethanol Content In Fruit Juices Using Cielab Color Space And Chemometrics Via Smartphone-Based Digital Image Colorimetry, Chairul Ichsan, Yasir Amrulloh, Desti Erviana

Makara Journal of Science

This study aims to investigate the optimal color space and chemometric technique for digital image colorimetry to determine ethanol content (% v/v) in apple, orange, and grape juices, using potassium dichromate (K2Cr2O7) under acidic conditions. The accuracy of colorimetric–chemometric integration across various color spaces (RGB, HSV, CIELab, CMYK, CIELuv, CIEXYZ, and CIELch) was benchmarked against UV–Vis spectrophotometry using metrics such as coefficient of determination (R²), mean absolute percentage error (MAPE), and root–mean–squared error (RMSE). Various chemometric techniques (PLS, PCR, MLR, multivariable–SVR, and multivariable NN regression) were evaluated. Results demonstrate that combining the CIELab color …

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Synthesis, Molecular Characteristics, And Antibacterial Assessment Of Marine Hydroid Aqueous Extract-Based Silver Bio-Nanoparticles, Fredryk Mandey, Aulia Rhamdani Arfan, Rugaiyah Andi Arfah Mar 2024

Synthesis, Molecular Characteristics, And Antibacterial Assessment Of Marine Hydroid Aqueous Extract-Based Silver Bio-Nanoparticles, Fredryk Mandey, Aulia Rhamdani Arfan, Rugaiyah Andi Arfah

Makara Journal of Science

This investigation aims to synthesize, analyze the molecularity, and test the ability of bacterial inhibition capability of silver nanoparticles that have been synthesized by simply mixing silver nitrate and aqueous extracts of marine natural products with and without the addition of amylum as a stabilizing agent. This research, with and without the addition of amylum as a stabilizing agent, obtained 39.0 and 55.2 mg of solids of round-shaped morphology silver nanoparticles with diameters of 87.9 and 103.0 nm., respectively. In addition, the antibacterial testing assay against Staphylococcus aureus and Escherichia coli showed some considerably good results. S. aureus with the …

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Advancements In Characterization Of Ancient Potteries From Southeast Asia: A Review Of Analytical Techniques, Chitnarong Sirisathitkul Mar 2024

Advancements In Characterization Of Ancient Potteries From Southeast Asia: A Review Of Analytical Techniques, Chitnarong Sirisathitkul

Makara Journal of Science

Ancient potteries offer valuable information regarding technological advancements, life dynamics, cultural diversity, and trade routes in the past. Earthenware, stoneware, and porcelain from Southeast Asia have been characterized using several analytical techniques, as reviewed in this article. Fluorescent and diffracted X-rays give rise to elemental and phase compositions, respectively. Examination of molecular bonds requires vibrational spectroscopy, which is useful for the identification of organic materials in ancient potteries. With the advent of portable X-ray fluorescence and Raman spectrometry, on-site analysis of archeological ceramics is now possible. For in-depth analysis, synchrotron light sources can provide new insights into artifacts through X-ray …

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Synthesis, Structural And Thermal Studies Of Dl-Alanine Potassium Di- Chromate Single Crystals, Sundararaj Lincy Mary Ponmani, Soundararajan Gnanakkan Pushpalatha Gracelin, Somasundaram Selvakumar, Subbaiah Chelladurai Vella Durai Mar 2024

Synthesis, Structural And Thermal Studies Of Dl-Alanine Potassium Di- Chromate Single Crystals, Sundararaj Lincy Mary Ponmani, Soundararajan Gnanakkan Pushpalatha Gracelin, Somasundaram Selvakumar, Subbaiah Chelladurai Vella Durai

Makara Journal of Science

Amino acids and their complexes are organic or semiorganic materials that have attracted considerable attention because they can be easily used in optical storage devices. DL-alanine is one of the rare amino acids that crystallizes in anoncentrosymmetric group. This article demonstrates how DL-alanine potassium dichromate (DAPC) single crystals have shown sufficient growth. DAPC crystals were analyzed by single crystal X-ray diffraction and powder X-ray diffraction. Using thermogravimetric analysis/differential thermal analysis (TGA/DTA) and differential scanning calorimetry, this work also examined the melting point, thermal stability, decomposition point, and other thermal parameters of the DAPC crystals. Results show that the decomposition point …

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Synergistic Effect Of Acylpyrazolone Integrated With Multiwalled Carbon Nanotubes On The Electrochemical Analysis Of Ascorbic Acid, Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, Norhayati Hashim, Anwar Ul-Hamid, Mohamad Idris Saidin, Suyanta Suyanta, Sofian Ibrahim Mar 2024

Synergistic Effect Of Acylpyrazolone Integrated With Multiwalled Carbon Nanotubes On The Electrochemical Analysis Of Ascorbic Acid, Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, Norhayati Hashim, Anwar Ul-Hamid, Mohamad Idris Saidin, Suyanta Suyanta, Sofian Ibrahim

Makara Journal of Science

Square wave voltammetry, cyclic voltammetry, chronocoulometry, and electrochemical impedance spectroscopy were employed to assess ascorbic acid’s electrochemical behavior in multiwalled carbon nanotubes (MWCNTs)/carbon paste electrode (CPE) modified by 1-phenyl-3-methyl-4-metafluorobenzoyl-5-pyrazolone (HPMmFBP). The ascorbic acid’s irreversible oxidation peak appeared at approximately 0.5 V. The shifting of the peak potential at the pH range of 6.0–8.4 showed the involvement of protons in the ascorbic acid oxidation. Moreover, the shifting of the peak potential with scan rate in the range of 0.07–0.4 V/s confirmed that the oxidation reaction was irreversible. Under optimized conditions, the oxidative peak current showed linear dependence on the ascorbic acid’s …

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In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori Mar 2024

In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori

Makara Journal of Science

Aedes aegypti is a primer vector of dengue virus (DENV) and chikungunya virus (CHIKV). The susceptibility of mosquitoes to DENV and CHIKV depends on their recognition receptor of pathogens. C-type lectins (CTLs) are an important mediator of virus infection in A. aegypti. This study aims to identify potential receptors and determine the binding affinity between ligand–receptor interaction, CTLs and virus envelopes (DENV-1, 2, 3, and 4 and CHIKV) interaction based on in silico analysis. Sample sequences were obtained from GenBank (NCBI), and 10 CTLs were acquired from VectorBase. Homology modeling based on a minimum standard of 20% was processed …

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Implementation Of Digital Health In Addressing Global Threats: Lessons From The Use Of Technology During Covid-19 Pandemic In Indonesia, Naili Shifa, Anisa Tiasari, Kemal N. Siregar Feb 2024

Implementation Of Digital Health In Addressing Global Threats: Lessons From The Use Of Technology During Covid-19 Pandemic In Indonesia, Naili Shifa, Anisa Tiasari, Kemal N. Siregar

Kesmas

This research conducted a systematic literature review to explore the implementation of digital health in Indonesia, focusing on the digital health policies, usage during the COVID-19 pandemic, benefits, and lessons learned. The study identified 10 relevant journals through database searches and analyzed the trends in publication, productive journals, and top institutions involved in digital health research. The findings revealed an increasing interest in digital health, with a growing number of published articles from 2021 to 2023. ScienceDirect emerged as the most productive journal, followed by PubMed and MDPI. The University of Indonesia and the University of Gajah Mada were the …

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Road Traffic Noise Annoyance And Cardiovascular Disease Risk In Population: A Case Series Study In Kota Bharu, Malaysia, Faridah Naim, Nurin H M Nasir Feb 2024

Road Traffic Noise Annoyance And Cardiovascular Disease Risk In Population: A Case Series Study In Kota Bharu, Malaysia, Faridah Naim, Nurin H M Nasir

Kesmas

Noise pollution can cause annoyance, significantly threatening the population’s health and well-being. This study aimed to find an association between road traffic noise exposure and cardiovascular disease (CVD) risk among residents in Kota Bharu, Malaysia. This descriptive study used a case series approach and surveyed 34 residents in selected residential areas near main roads. An adapted questionnaire was distributed to residents using a purposive sampling method. Questions related to sociodemographic information, self-reporting about CVD, and road traffic noise assessment were asked to investigate the underlying risk factors for CVD. The average score of CVD assessment was classified as moderate risk. …

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Effects Of Maternal Anthropometry On Infant Anthropometry: A Cross-Sectional Study At Public Hospital X In Ternate, Indonesia, Yuni Nurwati, Hardinsyah Hardinsyah, Sri Anna Marliyati, Budi Iman Santoso, Dewi Anggraini Feb 2024

Effects Of Maternal Anthropometry On Infant Anthropometry: A Cross-Sectional Study At Public Hospital X In Ternate, Indonesia, Yuni Nurwati, Hardinsyah Hardinsyah, Sri Anna Marliyati, Budi Iman Santoso, Dewi Anggraini

Kesmas

Infant anthropometry is an indicator of neonatal survival. This study aimed to determine the effects of maternal anthropometry on estimating infant anthropom­etry. This cross-sectional study on 173 pregnant women at Public Hospital X in Ternate, Indonesia, was conducted from August 2018 to March 2023. The el­igible criteria were pregnant women aged ≥18 years, single pregnancy, and antenatal care (ANC) visits to the same hospital. The variables used included ma­ternal anthropometric measurements (body weight, body height, third-trimester weight (TTW)), gestational weight gain (GWG), education, age, ANC visits, and gestational age at delivery (GAD). A logistic regression model was employed to estimate …

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Analysis Of Community-Based Pattern Of Water Demand And Supply, Ishaku Dibal Joshua, Abdullahi Chado Salihu, Ayuba Musa Mshelia, Nchedo Nnedinma Ubachukwu Dec 2023

Analysis Of Community-Based Pattern Of Water Demand And Supply, Ishaku Dibal Joshua, Abdullahi Chado Salihu, Ayuba Musa Mshelia, Nchedo Nnedinma Ubachukwu

Journal of Environmental Science and Sustainable Development

Gombi rural community of Adamawa state, Nigeria, has witnessed significant growth in human population, which has contributed to an increase in water demand. Thus, the study analyzed water demand and supply patterns in Gombi communities of Adamawa State, Nigeria. A structured questionnaire was used for data collection. Descriptive statistics such as mean and percentages and inferential statistics like Analysis of Variance (ANOVA), chi-square, and linear regression were adopted for the analysis. The results on socioeconomic characteristics showed that the majority were females, with low household income levels, large household sizes, and in their active ages. Hand-dug well water was the …

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Measuring The Performance Of Sdgs In Provincial Level Using Regional Sustainable Development Index, Nurafiza Thamrin, Ika Yuni Wulansari, Puguh Bodro Irawan Dec 2023

Measuring The Performance Of Sdgs In Provincial Level Using Regional Sustainable Development Index, Nurafiza Thamrin, Ika Yuni Wulansari, Puguh Bodro Irawan

Journal of Environmental Science and Sustainable Development

Measuring the national and sub-national progress in achieving such globally adopted development agendas as Sustainable Development Goals (SDGs) is particularly challenging due to data availability and compatibility of indicators to measure SDGs, especially in Indonesia. This paper attempts to measure the performance of sustainable development at the regional level in Indonesia by newly constructing a multidimensional composite index called the Regional Sustainable Development Index (RSDI). RSDI comprises four dimensions, covering comprehensive economic, social, environmental, and governance indicators. By applying factor analysis, the paper assesses the uncertainty of RSDI and the sensitivity of its composing indicators, then further investigates the relationship …

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Conversion Of Cellulose To 5-Hydroxymethylfurfural As Sustainable Energy: A Bibliometric Analysis By Vosviewer, Royyan Faradis, Ardiansyah Bagus Suryanto, Irmina Kris Murwani Dec 2023

Conversion Of Cellulose To 5-Hydroxymethylfurfural As Sustainable Energy: A Bibliometric Analysis By Vosviewer, Royyan Faradis, Ardiansyah Bagus Suryanto, Irmina Kris Murwani

Journal of Environmental Science and Sustainable Development

The developments of the global economy and society impact resources and the environment. This condition requires an alternative to find new, safe, and sustainable energy types. The conversion of cellulose to 5-hydroxymethylfurfural (5-HMF) has become a significant area of research interest. It has triggered the development of research directions related to biomass and energy because it can be an intermediary source for making polymers, solvents, pharmaceuticals, and biofuels. The primary objective of this study is to give a bibliometric analysis of 1753 reports on the development of research on cellulose conversion to 5-HMF from 1965 to 2021. The data were …

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Combined Risk Based Inspection And Fault Tree Analysis For Repetitive 3-Phase Line Piping Leakage At West Java Offshore Topside Facility, Dona Yuliati, Akhmad Herman Yuwono, Datu Rizal Asral, Donanta Dhaneswara Dec 2023

Combined Risk Based Inspection And Fault Tree Analysis For Repetitive 3-Phase Line Piping Leakage At West Java Offshore Topside Facility, Dona Yuliati, Akhmad Herman Yuwono, Datu Rizal Asral, Donanta Dhaneswara

Journal of Materials Exploration and Findings

Hydrocarbon releases might result in serious consequences in various aspects. In addition to the contribution to environmental pollution, repetitive leakages need high repair costs. This study aim is to minimize potential repetitive leakage for other typical 3-phase piping systems. We conducted the risk assessment by adopting Risk Based Inspection (RBI) API 581 to identify risk level, calculating piping lifetime, recommended inspection plan and mitigations. The most relevant root causes can be obtained through quantitative Fault Tree Analysis (FTA). Observation and investigation was taken from eight 3-phase piping systems that experienced repetitive leakages. It has been found that the risk level …

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Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, Agus Mulyadi Hasanudin, Eddy Sumarno Siradj Dec 2023

Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, Agus Mulyadi Hasanudin, Eddy Sumarno Siradj

Journal of Materials Exploration and Findings

The production of metal and alloy products requires the use of heat treatment, when during the heat treatment process, quenching is a crucial step. The quenching medium can be anything from water, a salt bath, oil, air and gas. In a vacuum furnace, pressurized gas, most frequently nitrogen (N2) gas, serves as one of the quenching mediums. One of the drawbacks of the quenching process is the distortion and dimensional change of the parts. This paper aims to investigate the influence of nitrogen gas quenching pressure on the distortion and dimensional change of aerospace actuator gear planet parts …

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E-Governance: The Implication Of Next Social Generation Welfare Information System, Yaya Mulyana Abdul Aziz, Andre Ariesmansyah Dec 2023

E-Governance: The Implication Of Next Social Generation Welfare Information System, Yaya Mulyana Abdul Aziz, Andre Ariesmansyah

Smart City

Accelerating bureaucracy can be performed by e-governance present in order to improve the quality of government administration in the world. E-governance draft is closely related to the development of information and communication technology (ICT) globally. One form of embodiment of e-governance is the implementation of a smart city. smart cities are expected to be able to become a liaison between the demands of the community in appropriate, effective, and efficient services from the city government, by utilizing ICT. There are various related definitions of smart city in this world. One of them is as explained by Nam and Pardo who …

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Oxidation Of Ethanolamine By Potassium Permanganate In The Presence And Absence Of Sodium Dodecyl Sulphate: A Kinetic Study In An Acidic Medium, Dayo Latona Dec 2023

Oxidation Of Ethanolamine By Potassium Permanganate In The Presence And Absence Of Sodium Dodecyl Sulphate: A Kinetic Study In An Acidic Medium, Dayo Latona

Makara Journal of Science

The kinetics of ethanolamine oxidation by acidified KMnO4 was investigated in the absence and presence of sodium dodecyl sulfate (SDS) was investigated using a pseudo-first-order kinetics approach, with [ethanolamine]o >> [KMnO4]o. The measurements were conducted at λmax = 525 nm using an ultraviolet/visible-1800 Shimadzu spectrophotometer. The stoichiometry showed that 2 moles of KMnO4 were consumed by 5 moles of ethanolamine in the aqueous medium. The reaction orders in both the aqueous and micellar media remained the same with a first-order dependence on [KMnO4] and [ethanolamine] and a fractional-order dependence on [H …

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Electro-Optical Effect Of 4-N-Alkyl-Sulfanyl-4' Isothiocyanate-Biphenyl Liquid Crystal Homologous Series Under Terahertz Frequency: A Theoretical Approach, Yogesh Kumar, Narinder Kumar Dec 2023

Electro-Optical Effect Of 4-N-Alkyl-Sulfanyl-4' Isothiocyanate-Biphenyl Liquid Crystal Homologous Series Under Terahertz Frequency: A Theoretical Approach, Yogesh Kumar, Narinder Kumar

Makara Journal of Science

This work presented the electro-optical effect of the homologous series 4-n-alkyl-sulfanyl-4'-isothiocyanate-biphenyl (N1SC13H8-SH2n+1Cn) under an electric field with terahertz (THz) frequency. The increase in alkyl sulfanyl chain length reduces the birefringence but increases the order parameter in THz frequency. An inverse relationship exists between the birefringence and order parameter. Meanwhile, the increase in alkyl sulfanyl chain length increases the refractive index with an even–odd effect. Birefringence, refractive index, order parameter, and director angle show an even–odd effect in the THz frequency range. The calculation is performed between 1 and 1,200 THz frequency. The isothiocyanate stretching corresponding to …

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Free-Radical Scavenging Activity And Total Phenolic Compounds Of Red And Green Poinsettia Leaves (Euphorbia Pulcherrima Willd.) From Lombok Island, Handa Muliasari, Baiq Sopiah, Emmy Yuanita, Baiq Nila Sari Ningsih Dec 2023

Free-Radical Scavenging Activity And Total Phenolic Compounds Of Red And Green Poinsettia Leaves (Euphorbia Pulcherrima Willd.) From Lombok Island, Handa Muliasari, Baiq Sopiah, Emmy Yuanita, Baiq Nila Sari Ningsih

Makara Journal of Science

To determine the free-radical scavenging activity and total phenolic content of the ethanol extract of Poinsettia leaves (Euphorbia pulcherrima Willd.) from Lombok Island, we used the 1,1-diphenyl-2-picrylhydrazyl method and expressed the total phenolic content as gallic acid equivalent (GAE) per gram of ethanol extract. The results show the strong antioxidant activity (79.77 ppm) of the ethanol extract of red Poinsettia leaves and the moderate antioxidant activity of green Poinsettia leaves (118.350 ppm). The ethanol extracts of red and green Poinsettia leaves possessed an average of 63.276 ± 0.228 and 22.715 ± 0.090 mg GAE/g extract total phenolic contents, respectively. …

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Enzymatic Screening And Genotypic Characterization Of Thermophilic Bacteria From The Hot Springs Of Sarawak, Malaysia, Seng Chiew Toh, Samuel Lihan, Sui Sien Leong, Azizul Hakim Lahuri, Wai Cheong Woon, Wing Woh Ng Dec 2023

Enzymatic Screening And Genotypic Characterization Of Thermophilic Bacteria From The Hot Springs Of Sarawak, Malaysia, Seng Chiew Toh, Samuel Lihan, Sui Sien Leong, Azizul Hakim Lahuri, Wai Cheong Woon, Wing Woh Ng

Makara Journal of Science

Owing to their eccentric thermostable ability, thermophiles are among the most utilized extremophiles in various industries, such as manufacturing, and clinical research. Researchers believe that many unknown thermophiles are yet to be discovered. This study aimed to genotypically characterize the diversity of thermophiles and screen them for the potential production of enzymes in the recreational hot springs located at Northwest Coast of Borneo. Water samples were collected at 45 °C–50 °C from Annah Rais and Panchor hot springs during the sampling period from January 2018 to January 2019. Three samples (water and sediment) were collected twice in a 3-week interval …

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An Inkjet-Printed Graphene Oxide–Poly(3,4-Ethylenedioxythiophene) Poly(Styrene Sulfonate) Electrode For Nitrite Detection In Water, Budi Riza Putra, Weni Anindya, Mohamad Rafi, Ika Kartika, Yudi Nugraha Thaha, Aga Ridhova, Wulan Tri Wahyuni Dec 2023

An Inkjet-Printed Graphene Oxide–Poly(3,4-Ethylenedioxythiophene) Poly(Styrene Sulfonate) Electrode For Nitrite Detection In Water, Budi Riza Putra, Weni Anindya, Mohamad Rafi, Ika Kartika, Yudi Nugraha Thaha, Aga Ridhova, Wulan Tri Wahyuni

Makara Journal of Science

In this study, a screen-printed electrode (SPE) for nitrite (NO2−) sensing was fabricated through an inkjet printing technique using a commercial printer machine and preparing an ink composite solution containing graphene oxide (GO) and poly(3,4 ethylenedioxythiophene) poly(styrene sulfonate) (PEDOT:PSS) as conductive materials. The optimum ink materials for SPE fabrication comprised GO and PEDOT:PSS with binders that resemble the viscosity of commercial ink. The surface topography of the fabricated SPE, which was characterized using scanning electron microscopy and atomic force microscopy, showed a smoother surface compared to the commercial screen-printed carbon electrode, with conductive ink materials deposited primarily …

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Editorial: The Public Health Scholars As The Health Leaders, Al Asyary, Meita Veruswati, Putri Bungsu Machmud, Indri Hapsari Susilowati Nov 2023

Editorial: The Public Health Scholars As The Health Leaders, Al Asyary, Meita Veruswati, Putri Bungsu Machmud, Indri Hapsari Susilowati

Kesmas

No abstract provided.

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Composite Index Of Anthropometric Failure And Early Childhood Cognitive Development Based On The 2018 Indonesian Basic Health Research Data, Safira Zamrudiani, Abdul Wahab, Rosalia Kurniawati Harisaputra Nov 2023

Composite Index Of Anthropometric Failure And Early Childhood Cognitive Development Based On The 2018 Indonesian Basic Health Research Data, Safira Zamrudiani, Abdul Wahab, Rosalia Kurniawati Harisaputra

Kesmas

Delays in early childhood cognitive development may have profound long-term implications on health and life expectancy. Optimal nutrition supports early life development, including a child's cognitive development. This study aimed to determine the association between the Composite Index of Anthropometric Failure and early childhood cognitive development among children aged 36-59 months in Indonesia. This cross-sectional study utilized data from the 2018 Indonesian Basic Health Research that involved 18,027 participants aged 36-59 months. This study outcome demonstrated that children who were stunted-underweight were potentially susceptible to delayed cognitive development compared to those with normal nutritional status (aOR = 1.30; 95% CI …

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Phytochemical Constituent And Antioxidant Activity Evaluation Of Red Seaweed Eucheuma Sp., Ade Arsianti Oct 2023

Phytochemical Constituent And Antioxidant Activity Evaluation Of Red Seaweed Eucheuma Sp., Ade Arsianti

Indonesian Journal of Medical Chemistry and Bioinformatics

Oxidative stress is a condition in which there is an imbalance between production of free radicals and protective response via antioxidant system. There are endogenous and exogenous antioxidants, however as age increases, there is a reduction in endogenous antioxidant, thus the search for potential exogenous antioxidants which could be derived from natural resources are needed. Indonesia is a megabiodiversity country which has more than 30,000 species of plants and animals. Red seaweed Eucheuma sp. is one of marine macroalgae species which shows potent biological activities. This study aims to determine the phytochemical constituent and to evaluate the antioxidant activity of …

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