bluuebunny/crossref_metadata_2025 huggingface dataset:
Dye and activated carbon from Canarium ovatum Engl. as photosensitizer and counter electrode for Titania-based dye sensitized solar cell
Authors: Gasga K
Published: May 2021

Natural dye from exocarp and activated carbon from charred shells of Canarium ovatum Engl nut was used in the fabrication of dye sensitized solar cell (DSSC). Anatase titania (titanium dioxide, TiO2) nanoparticles was used as semiconducting layer deposited on a transparent conductive indium tin oxide glass using doctor blade method. TiO2 film thickness and soaking time in dye were varied to show response in terms of fill factor (FF), short circuit current density (Jsc), open circuit photovoltage (Voc), and conversion efficiency (η). In a 2.0 cm2 active surface area tested under solar irradiance, assembled DSSC at optimum conditions garnered 0.768 desirability with FF, Jsc, Voc and n values of 0.601, 6.293 mA/cm2, 0.446 V, and 1.792, respectively.
Fourier Transform Infra-Red spectrophotometry observation to find appropriate wavelength for non-invasive blood glucose level measurement optical device
Authors: Alatas H , Suryana Y , Pambudi S , Widayanti T , Jenie R P , Zaheri R , Aridarma A , Rahayu S K , Riadhie T S , Rahmawaty V , Har N P , Zuhri M , Sumaryada T , Irzaman
Published: May 2021

The appropriate wavelength is essential for non-invasive blood glucose level measurement optical device. We conducted this experimental observation to find the usable wavelength candidate for non-invasive blood glucose level measurement optical device in 1000 nm to 2500 nm range. We run this observation in Prodia Bogor and Food Processing and Crops Technology Lab, Faculty of Agricultural Engineering, IPB University, July 2019. We obtained fasting, 15 mnt postprandial, and 30 mnt postprandial blood sample from 10 randomly selected consenting non blinded healthy adult subjects between 18 to 60 years old. We measured spectrophotometric absorbance for each blood sample. We did the measurement using BUCHI NIR FLEX 500. We compared the result to blood glucose level by standard gold measurement. We also compared the Pearson correlation, and the standard deviation of all samples to then-existing wavelength source LED provided by Thorlabs. We found that the highest absorbance and standard deviation wavelength is at 1939 nm. Wavelength LEDs candidates that represent measuring blood glucose levels is 1200, 1300, 1450, 1750, and 1950 nm. We did not find a severe adverse effect from each participant. Researchers should confirm the trial results with in vivo human observation.
Student’s misconception and thinking style on modern physics course
Authors: Halim A , Nurhasanah  , Zainuddin  , Musdar  , Elisa  , Mahzum E , Irwandi I
Published: May 2021

This study aims to determine the relationship between misconceptions and thinking styles of students in modern physics course and to determine which type of thinking style is more dominant in relation to misconceptions. This type of research is a survey study with a quantitative approach. The samples in this study were 60 students who have followed the modern physics course. Data collection used a two-tier diagnostic test on modern physics and a thinking style questionnaire. The results of the analysis with the correlation test found that the types of thinking style Concrete Sequential (CS), Abstract Sequential (AS), and Random Abstract (RA) are negatively correlated with misconceptions or it can be said that there is almost no correlation with misconceptions, namely (-0.024), (-0.113) and (-0.082). Meanwhile, the type of concrete random thinking style (CT) has a positive correlation with misconceptions, but the relationship is weak (0.303). Based on these results, it can be said that the types of thinking styles of students tend to have no correlation with misconceptions. Even though the correlation between the two is low, it is necessary to pay attention to the thinking style of students in conveying concepts in modern physics.
Increasing critical temperature on BPSCCO superconductors with addition of Al2O3
Authors: Nasution S F , Humaidi S , Imaduddin A , Darsono N , Nugraha H
Published: May 2021

We have investigated the effect of addition of Al2O3 in the manufacture of the BPSCCO superconductors using solid state reaction method. Precursors with consist of Bi2O3, PbO2, SrCO3, CaCO3, and CuO powders were ground using mortar agate for 3 h. The samples were heated at 300°C for 6 h to remove the moisture in the powders, and then ground again for 6 h. Then the samples were calculated at 820°C for 20 h and then Al2O3 (1wt% and 2wt%) were added and ground again. The powders were compacted with a diameter of 10 mm and a thickness of 2 mm and then sintered at 850°C for 30 h. The characterizations were carried out by using Cryogenic Magnet to determine the superconductivity properties, SEM-EDX to analyze the morphology and XRD to determine the phase formed. The resistivity versus temperature results showed the increase of Tc with the addition of Al2O3. Sample with 1wt% Al2O3 has Tconset of 90 K and Tczero of 66 K, when the sample with 2wt% Al2O3 has Tconset of 94 K and Tczero of 73 K. The morphology formed looks less homogeneous, the crystalline granules are melt-shaped, clumpy and there are porosity.
Identification of total suspended solid (TSS) in the Aceh waters from ocean color
Authors: Syawani U , Haditiar Y , Ikhwan M , Wafdan R , Muhammad M , Setiawan I , Jalil Z , Chaliluddin M A , Rizal S
Published: May 2021

The suspended sediment in Aceh waters was analysed from remote Sensing Reflectance of Aqua MODIS resolution 4 km. Two equations from previous studies were used to determine the magnitude and distribution of suspended sediment concentrations in Aceh waters during 2018. The results show the suspended sediment concentrations from the two equations are relatively the same even though they differ spatially (offshore and near the coast of Aceh waters). Based on Zhan et al. equation, the suspended sediment in Aceh waters have a maximum value of 0.786 mg/L and a minimum value of 0.589 mg/L. Meanwhile, based on Zhang et al. equation, the maximum and minimum suspended sediment in Aceh Waters are 0.639 mg/L and 0.271 mg/L, respectively. Based on these two equations, Krueng Kluet estuary located in the western part of Aceh has the highest suspended sediment. In contrast, Krueng Peusangan estuary in the eastern part of Aceh has a low sediment concentration. The highest suspended sediment in Aceh waters occurs in November to December and the low period is in April to September. The heavy rainfall encourages freshwater runoff and high suspended sediment in the mouth of the Aceh waters, especially in the western part of Aceh.
Analysis of students’ ability in completing HOTS-based Basic Physics questions
Authors: Halim A , Mastura I , Soewarno  , Elisa  , Mahzum E , Farhan A , Irwandi I
Published: May 2021

This study aims to determine students’ higher order thinking skills in solving HOTS-based Basic Physics questions. The research method used is descriptive method with a quantitative approach. The research subjects were 23 students of the second semester of the Physics Education Study Program. The data collection technique used was a test by giving questions consisting of three questions covering questions to analyse, evaluate and create. Based on the results of data analysis, it is known that students’ high-order thinking skills in solving HOTS-based Basic Physics questions are in the poor category with the following details: The percentage of students who have high-order thinking skills is very good category is 15%, good category is 10%, category 25% enough, 35% less category and 15% very poor category. The inference from these results is that in the evaluation of the Basic Physics subject, it is necessary to add more high-level standard questions.
Binary logistic regression for identification of high school student interest in Banda Aceh city in continuing study at Universitas Syiah Kuala
Authors: Nurhasanah  , Rusyana A , Fitriana A R
Published: May 2021

Universitas Syiah Kuala is the oldest university in Aceh. The campus has the nickname of the jantong hate campus to the Acehnese people, which of course can be interpreted as the campus of pride of the Acehnese people. Universitas Syiah Kuala increased its accreditation status from C to A accreditation awarded by the research, technology and higher education ministry. This showed a very significant quality of improvement. With this condition a study was conducted on the interest of high school students in the Banda Aceh City in choosing Universitas Syiah Kuala as a place to study. This study aims to determine the factors that influence the interest of Banda high school students in continuing their studies to Universitas Syiah Kuala and get a model of interest in the Banda Aceh city students through a binary logistic regression approach. The results show that the factors that influence students’ interest in continuing their studies at Universitas Syiah Kuala are the ability to be affiliated with others, goals, and expectations. With the binary logistic regression model obtained, it can be seen the tendency of students to continue their studies at Universitas Syiah Kuala.
The challenges experienced by teachers in online workshop during the COVID-19 pandemic
Authors: Johar R , Elizar E , Annisa D , Mailizar M
Published: May 2021

COVID-19 pandemic has changed many aspects of our everyday life, including education. Schools and universities are closed, so that teaching and learning activities must be modified from traditional face-to-face to online learning. Also, professional development programs are affected. However, online program does not always run smoothly and the participants may encounter some challenges. This study investigates the challenges experienced by mathematics teachers in online workshops on Realistic Mathematics Education. This qualitative research involved 11 mathematics teachers in Banda Aceh, Indonesia, joined the online workshop voluntarily. The instrument used in this study was an interview sheet. The results of the interview regarding the challenges during the online workshop showed four categories of challenges: technical issues, facilities, cooperation between groups, and collaboration with facilitators. The finding of the study is expected to provide insight on how to improve future online workshop.
Mathematical creative thinking level on polyhedron problems for eight-grade students
Authors: Junaedi Y , Wahyudin  , Juandi D
Published: May 2021

Mathematical creative thinking is needed by students in addition to other abilities because it can provide broad thinking to get new ideas or new solution of mathematical problemsolving. The aim of this research is to describe mathematical creative thinking level on polyhedron problems for eight-grade students. This research was conducted at a senior secondary school in Indonesia with a total of 35 students in year 8. This type of research is a case study with inductive data analysis techniques which include: data reduction, data display, drawing conclusions and verification. The research instrument consisted of 4 test descriptions based on the aspects of mathematical creative thinking ability, interview guidelines and documentation. The result of this research concluded that students with a high level of mathematical creative thinking ability tend to solve polyhedron problems in the aspects of originality, fluency, flexibility, and elaboration. Students with a medium level of mathematical creative thinking ability tend to give one overall correct answer to polyhedron problems in the aspects of originality, fluency, flexibility, and elaboration. Students with low level mathematical creative thinking ability tend to give incorrect answers to polyhedron problems in the aspects of originality, fluency, flexibility, but in the elaboration aspect, it gives one correct answer even though it is not detailed.
Prospective mathematics teachers’ concept image on the limit of a function
Authors: Sulastri R , Suryadi D , Prabawanto S , Cahya E , Siagian M D , Tamur M
Published: May 2021

The concept of limit is one of the prerequisite subjects in studying calculus. Previous studies indicate that the use of the limit concept in learning that is not in accordance with the limit concept in mathematics. This study aims to describe the concept image of prospective mathematics teachers on the concept of limit functions and the causes of the concept image. This qualitative study used the phenomenology approach, involving seven mathematics students in the fifth semester at a university in Bandung, Indonesia, who were selected based on the results of a written test. The data were obtained from the results of written tests on the concept of limit function and interviews and analysed descriptively. The results showed that students understood the concept of limit function in the same way that limit is an unreachable function. This causes the definition of limit formally using ε-δ is not properly understood. In this case, a comprehensive study of the limit function is needed at the beginning of calculus learning and should be an important concern for lecturers of calculus.
An analysis of students’ mathematical literacy skills assessed from students’ learning style
Authors: Sakinah M , Avip P B
Published: May 2021

This study aims to determine students’ mathematical literacy skills based on their learning styles. This descriptive research used a learning style questionnaire, a students’ mathematical literacy test to determine students’ mathematical skills, and interviews to complement the data. The data analysis included analyzing the learning style and mathematical literacy tests with data validity using the triangulation method. This study revealed several results: 1) The mathematical literacy skills of students with visual, auditory, and kinesthetic learning styles were still deficient, where only 14% of students answering the mathematical literacy questions correctly; 2) The mathematical literacy skills of students with a kinesthetic learning style were better than students’ with visual and auditory learning styles; 3) Students with a visual learning style had been able to formulate the given mathematical problems, while the use of mathematical concepts and interpreting mathematical problems were still lacking; 4) Students with an auditory learning style had the lowest skills in formulating mathematical problems so that they mistakenly used basic mathematical concepts; and 5) Students with a kinesthetic learning style were able to formulate and use mathematical concepts properly and correctly despite still lack of interpreting mathematical problems.
Error analysis in solving the linear equation system of three variables using Polya’s problem-solving steps
Authors: Wiyah R B , Nurjanah
Published: May 2021

Recently, students still often have difficulties and share common mistakes in solving the linear equation system of three variables. This qualitative descriptive research describes the errors and causes of students’ errors in solving the linear equation system of three variables using Polya’s problem-solving steps. The subjects were 33 students of Grade 10 Science at one of the Senior High School in Indralaya. The data collection techniques used observation, student worksheets, and interviews. The results showed there were several students’ errors and the causes of students’ errors in solving the problems. These errors are errors in identifying the known and asked information, errors in making mathematical models of problems, errors in calculations, errors in arranging the linear equation system of three variables, and errors in giving valid reasons for their answers. The causes of these errors are the limited time for understanding the problem, careless in doing calculations, forgetting the formulas, and lacking understanding of variables concept.
Improving students’ mathematical identity using games as learning media during the Covid-19 pandemic
Authors: Hima L R , Nusantara T , Hidayanto E , Rahardjo S , Murniasih T R
Published: May 2021

During the COVID-19 pandemic, Indonesia has applied digital learning methods for all school levels. It is undeniable that digital learning also brings out boredom for students. This saturation decreases student motivation to learn, coupled with anxiety about the uncertain pandemic situation. Decreased motivation and increased anxiety are related to the mathematical identity possessed by students. As a result of this decline, the mathematical identity of the students is also not good. This research was conducted to improve student mathematical identity by using games as learning media. Data were collected from two fifth-grade elementary school students who have a low-category mathematical identity. This research is qualitative research using a case study approach. The results showed that the games used as learning media succeeded in improving students’ mathematical identities. Other findings indicate that the circumstances around students, such as a pandemic, reduce students’ mathematical identity. Therefore, it is hoped that teachers’ creativity in developing students’ mathematical identities is expected because the development of students’ mathematical identities strongly depends on the treatment of the environment around them, such as teachers, friends, and even the learning media they use.
Methylation analysis of Igf2 / H19 Imprinting Control Region (ICR) in Type II Diabetes Mellitus induced mice using Methylation-Specific PCR
Authors: Tedjokusumo V L I , Chandra S P , Surjadjaja E , Artadana I B M , Putra S E D
Published: May 2021

The imprinting control region (ICR) is a region that controls imprinted expression of Igf2/H19 so that Igf2 will only be expressed from the paternal allele instead of the maternal allele. This research aimed to reveal if ICR methylation status’ change contributes to the emergence of type II diabetes Mellitus (T2DM) throughout the induction in mice model. The methylation changes were detected by methylation-specific PCR (MSP). The Control group was given a normal diet and buffer vehicle injection while treatment group was given a high fat diet (HFD) and six times 60 mg/kg mice body weight streptozotocin injection. The induction process was conducted for 12 weeks. The insulin tolerance test (ITT) was conducted on week 0, week 9, and week 12. The treatment’s mice group was successfully induced a significantly higher area under the curve (AUC) compared to the control mice (P < 0, 05). Moreover, ITT showed that diabetic induced mice had higher glucose levels at every time point of the test. Meanwhile, there were no evident ICR methylation changes through week 0 to week 12. Thus, ICR methylation is not proven to contribute to the emergence of T2DM.
Effect of Cellulose and Titanium Dioxide on the properties of Chitosan film
Authors: Rahmi  , Lubis S , Az-Zahra N
Published: May 2021

Chitosan film has attracted attention due to its advantages; it is easily modified due to numerous active sites. However, the use of chitosan film alone has limited applications. Therefore, it is necessary to modify chitosan film. In this study, chitosan was modified through addition of titanium dioxide and cellulose, extracted from grass (imperata cylindrica). Chitosan-cellulose-titanium dioxide composite film was prepared with different compositions of chitosan, cellulose and titanium dioxide. The result of the tensile test showed the addition of cellulose and titanium oxide improved tensile strength of the chitosan film. FTIR and XRD analysis confirmed the formation of chitosan-cellulose-TiO2 composite film.
Utilization of Palm Kernel Meal (PKM) as activated charcoal to remove organic pollutants
Authors: Fahmi A G , Abidin Z , Kusmana C , Noor E
Published: May 2021

Palm kernel meal (PKM) is a waste product from the palm oil industry. The objectives of this study are to synthesize activated charcoal from palm kernel meal and apply its ability to adsorb organic matter in water. Charcoal was prepared and activated by pyrolysis without the flow of the inert gasses method and characterized by Fourier-Transform Infrared (FT-IR), estimation surface area, and their adsorption of organic compounds such as oxalic acid and methylene blue. The product has polar and basal sites with hydroxy and carboxyl groups on the surface. The highest estimation surface area is 523 m2/g with 350 °C temperature pyrolysis. Adsorption data fit the Freundlich isotherm model for oxalic acid and Langmuir isotherm model for methylene blue that indicates interaction of active site on the surface charcoal with adsorbates. The absorption capacities of activated charcoal were 38.03 mmol/g absorbent and 12.49 mmol/g absorbent against methylene blue and oxalic acid, respectively. Therefore, PKM waste can be used to be a potentially viable activated charcoal for removing organic pollutants from aqueous solutions.
Synthesis and mesophase behaviour of Benzylidene-based molecules containing two Azomethine units
Authors: Jamain Z , Khairuddean M
Published: May 2021

The research work involves the synthesis and characterization of intermediates 4-heptyloxybenzaldehyde (1) and 4-dodecyloxybenzaldehyde (2). Five compounds with two Schiff base linking units were further synthesized by condensation reaction using aldehyde and 1, 4-phenylenediamine. These compounds include N, N’-dibenzyliden-benzen-1, 4-diamine (3);
N-benzyliden-N’-(4-chlorobenzyliden)benzen-1, 4-diamine (4);
N-benzyliden-N’-(4-methoxybenzyliden)benzen-1, 4-diamine (5);
N-benzyliden-N’-(4-heptyloxybenzyliden)benzen-1, 4-diamine (6) and N-benzyliden-N’-(4-dodecyloxybenzyliden)benzen-1, 4-diamine (7). These compounds were characterized using Fourier-Transform Infrared (FTIR), 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopy and CHN elemental analysis. Polarized Optical Microscope (POM) was used to detect liquid crystal mesophase(s) and their thermal behaviour was measured using Differential Scanning Calorimetry (DSC). Compounds 4, 6 and 7 showed the nematic phases, while compounds 3 and 5 were found to be non-mesogenic without any liquid crystal properties.
Virtual lab as distance learning media to enhance student’s science process skill during the COVID-19 pandemic
Authors: Usman M , Suyanta  , Huda K
Published: May 2021

The emergence of problems such as the COVID-19 pandemic that currently occurred interfere the implementation of teaching and learning activities in schools. Especially for science learning, it is not only about the content but also the processes to improve student’s skills, such as science process skills. Current technological advances make it possible to conduct distance learning using media such as virtual lab. This study aims to review the comparison of the effectiveness between virtual lab and traditional lab, the use of virtual lab on student’s science process skills, and the use of virtual lab as a medium of distance learning. This study uses a systematic literature review method with 22 selected articles. The results indicate that the use of virtual lab media has the same or even better effectiveness than traditional labs. The use of virtual lab enable to enhance student’s science process skills, especially in predicting and measuring. This is because the virtual lab media able to provide opportunities and flexibilities for students to conduct experiments by the level of ability and pace of learning each student, anytime and anywhere. Thus, the virtual lab media is feasible to be used as an alternative substitute method for distance learning.
Biophysical Aspects that Influence the Increase of Slum Area in the Sigli Region, Aceh, Indonesia
Authors: Hadi R , Achmad A , Fadhly N
Published: May 2021

The location with a high level of accessibility and affordability has a high development of built-up land, which in turn causes slum settlements. There are some biophysical factors, which can cause slum settlements, including road networks and city service centres. Pidie District is one of the districts in Aceh Province which has a slum prevalence of more than 50 hectares, where mostly are located in the District of Sigli City. For that reason, this current study aimed to identify the growth patterns of slum settlements in the Sigli City between 2008 and 2018 based on biophysical aspects. The approach used was spatial-based quantitative, where data on growth patterns of slum settlements were processed using ArcGis 10.6 software. Driving factors included were distance to roads, distance to river, distance to coastline, and distance to city service centre. The results showed that the change in land use into settlements was 101.33 Ha, of which 51.41 Ha were slum settlements. From this number, 26.84 Ha of slum settlements grew adjacent to the road, 14.66 Ha adjacent to the river, 5.49 Ha adjacent to the coastline, and 26.84 Ha adjacent to the city service centre.
The role of ICT as a media in learning activities before the COVID-19 pandemic: undergraduate perspective
Authors: Sumaimi M E , Susilawati
Published: May 2021

The crisis caused by COVID-19 has an impact on education in Indonesia, one of which is that classes are postponed due to the implementation of PSBB regulations. The education system is responding to the pandemic with an "emergency e-learning" protocol, with virtual learning. ICT is the main medium of learning with the help of technological resources which is often termed e-learning. Has great potential in the development of the education system by providing freedom of interaction without time and space boundaries. With the results of the descriptive analysis survey, the respondents were 63 students of the Sarjanawiyata Tamansiswa University and Tidar University. Respondents were dominated by female gender as 55 people (87.3%) and male respondents as 8 people (12.7%). Students considered ICT understanding to be very important 61.9% and believed that ICT could expand access to learning 66.7%, with internet usage by 90%, followed by PPT as an ICT tool that was often used by 87.9%. Also, there are obstacles faced by students such as lack of understanding of system operations (40%) and difficulty operating equipment as 36.7%. Thus, knowing students’ expectations will be a consideration for further research. Students have hopes of increasing the use of ICT in lecture activities by 80%-100%, such as increasing internet access by 70% to make it easier and faster.
Classification of traditional ulos of Batak Toba ssing probabilistic neural network
Authors: Siregar B , Panggabean I P S , Fahmi  , Hizriadi A
Published: May 2021

Ulos are commonly used in traditional Batak events. Ulos has many variations of pattern and the pattern almost similar to one another. Ulos also have different functions in its use. So, people are often wrong to call the name of Ulos because the similarity of its pattern. Therefore, the research is doing Ulos classification to increase the introduction of Batak Toba’s Ulos. In this research, the method used in classification is Probabilistic Neural Network method. The stages before classification are pre-processing, extraction feature using Gray Level Co-Occurrence Matrix, and then classified using Probabilistic Neural Network. The research uses 650 data to be used as training data and test data. After testing in this research, it was concluded that the Probabilistic Neural Network method had the ability to classify Ulos into five patterns namely Bintang Maratur, Ragi Hidup, Ragi Hotang, Mangiring and Sibolang. The result showed that the accuracy level is 80%.
Implementation of decision tree using C5.0 algorithm in preference and electability survey results on regional head election in Aceh
Authors: Marzuki M , Iqbal M , Nivada A , Sofyan H , Usman T , Nazaruddin N , Munawar M , Rasudin R
Published: May 2021

The decision tree is one of the methods of classification in data mining. There are many algorithms used to construct the tree model; one of them is C5.0 algorithm. The tree model with C5.0 algorithm was carried out based on the survey result dataset of the preference and electability of the regional head selection pre-campaign year 2018 in one of the districts in Aceh. The datasets consisted of 5 predictor variables, i.e. sub-districts, age, main occupations, highest education, and attracting factors from regional head candidate candidates. Variable categories of decisions ranged from candidates A, B, C, and D. The distribution of datasets was divided into training data and testing data using the k-fold cross-validation method. The optimum tree model formation was based on the accuracy value of model and coefficient of Kappa. The result showed that the best tree model was constructed using testing data on S = 10. The accuracy of the model and the Kappa coefficient were 0.8427 and 0.7208, respectively. There were three rules generated with five nodes. The main predictor variable contributing to the optimum model was the attracting factor of candidates and sub-districts.
Study of lime addition to sewer sedimentation soil to improve the soil properties for use as construction materials
Authors: Sundary D , Munirwan R P , Al-Huda N
Published: May 2021

Sewer sedimentation in general cannot be used directly as construction materials due to the behaviour which is hard when it is dry and weak and soft when it is wet. Several engineering treatments that can be taken to improve the soil properties including adding a chemical stabilization using a mixture of materials. The stabilized soil samples came from Lam Glumpang Village, Ulee Kareng District, Banda Aceh. The purpose of this study was to obtain mechanical soil parameters before and after stabilization with lime. This research was conducted by mixing lime and lime soil with variations of 2%, 4%, 6%, and 8% of the dry weight of the soil. According to the AASHTO classification system, the soil is classified as A-4 (8) soil type, namely moderate to poor silt soil with an index group of 8, and according to the USCS classification system it is classified as an inorganic silt soil type with the symbol ML, namely silt soil with low plasticity. The results showed some good improvement in soil properties. In general, the addition of lime which has a good effect on sewer sedimentation soil in the mixture proportion of 6%.
Establishing a new gravity reference station for geophysical investigation and educational purposes: comparison with satellite gravity data in Banda Aceh city, Indonesia
Authors: Irwandi I , Darisma D , Simanjuntak A V H , Sofyan H , Asrillah
Published: May 2021

Determining the gravity reference point in the form of the absolute gravity acceleration value is necessary for education and research purposes. Department of Physics, Universitas Syiah Kuala (USK), has had the Scintrex CG-5 gravimetersince 2013 and should have had one absolute gravity point around the campus. A new gravity reference point was made at the Tugu Field (Lapangan Tugu) USK, which was derived from the gravity reference point BMKG Mata Ie with an absolute gravity value of 978102.87 mGal. First, we measured the relative difference in gravity’s value between the two points using the Scintrex CG-5 gravimeter. The difference of gravity value at the Tugu Field with BMKG Mata Ie is 23.8356 mGal smaller so that the absolute gravity value is 978079.01 mGal. The result is consistent with the geological data where the rocks around BMKG Mata Ie are metamorphic rocks that began to form in the late Jurassic, while the strata at the Tugu Field consist of young alluvium in the Holocene epoch which has a lower rock density. To verify the absolute gravity value, it is compared with the gravity value obtained from the satellite TOPEX. Data from these satellites is around 978140.15 mGal with a difference of 61.14 mGal.
Computational models and experimental validation at the physics teacher training college using scilab and arduino™
Authors: Dibarbora Carlos
Published: May 2021

This work provides an overview of the main activities developed for an Information Technology course at Physics Teacher Training College-an 80 minutes per week, two semesters long course in a four-year physics teachers program-which incorporates the modelling process as a core topic. It proposes the implementation of software tools to aid this process, focusing mainly on physics models rather than technicalities associated with the underlying math, which is solved using numerical techniques. It also focuses on the experimental validation as a fundamental part of the process which in this case is solved using low cost and easy accessible materials as Tracker software or the Arduino boards and sensors, and describes the teaching strategies implemented to reach that goal, assessed through students’ productions.
The development of self-perception instrument of students’ critical thinking skills
Authors: Abdulah  , Wangid M N
Published: May 2021

Critical thinking skill is one of important skills in the 21st century. With critical thinking skills, people can observe a phenomenon from different perspectives. Therefore, it will lead individuals to think more critically in responding to information received. This study aimed to product self-perception instrument of students’ critical thinking skill that valid and reliable. This research used a modification from 6 steps of research by Borg and Gall. The credibility of instrument is observed from its validity, reliability, exploratory factor analysis, and validation result by the experts. To examine validity and reliability of this instrument, researchers adopted SPSS 23. Results showed that there were 13 items in self-perception instrument of critical thinking skills with a valid and reliable category. Exploratory factor analysis test results show that the 13 items that have been developed form 3 critical thinking skills factors, namely analysis, evaluation, and synthesis. In addition, results showed that the self-perception instrument of critical thinking skills which has been implicated is in the category of “very good” and it is highly valid to measure the levels of self-perception of critical thinking skills. For example in natural science learning activities.
Scientific literacy competency of senior high school students based on question formats
Authors: Putra N S , Agusnita
Published: May 2021

One of success indicators on educational process is the achievement of students in scientific literacy competency. We can identify the profile of students’ scientific literacy by giving them a test using scientific questions. The purpose of this research is to reveal student scientific literacy competency based on question formats in biology topics. The research took place at SMAN 10 Padang. The sample of this research were 44 grade X students. Sample collection method used was simple random sampling. The questions were taken from The Programme for International Student Assesment (PISA)’s E-Book (Take the Test: Sample Question From OECD’s PISA Assessment). PISA questions consist of three question formats including 48 objective questions, 5 compound questions, and 10 essay questions. We found that student scientific literacy scores from objective, compound, and essay questions formats are 50.66%, 35.91%, and 42, 72% respectively. The average of student scientific literacy competency score based on question formats is 43, 9%. The average score category is very low. In testing the students’ scientific literacy competency based on question formats, it was revealed that students are easier to answer objective questions than other question formats.
STEM-E: Fostering mathematical creative thinking ability in the 21st Century
Authors: Suherman  , Vidákovich T , Komarudin
Published: May 2021

Creative thinking is important in improving the formation and discovery of learning ideas in the 21st century. This study aims to determine differences in the ability of students’ mathematical creative thinking in learning STEM and Ethnomathematics (STEM-E). This research employed the experimental design with a simple random sampling technique to determine the sample. The population of this study was 300 junior high school students in Lampung Province, Indonesia. The data collecting technique used was a test instrument tested to see the improvement of mathematical creative thinking. Hypothetical testing used was one-way ANOVA with a significance level of 5%. We found that the average score of the class that applied the STEM-E learning model was 74.71, which is higher, compared to the STEM class with the average score of 72.10, and the control class with the average score of 67.88. It can be concluded that the STEM-E model can be used as an alternative solution for learning in the industrial era 4.0.
Layered heterostructure of planar and buckled phases of silicene
Authors: Jaroch Tomasz , Krawiec Mariusz , Zdyb Ryszard
Published: May 2021

Heterostructures made of two-dimensional (2D) materials became a topic of numerous studies due to their new and often unexpected properties. Typically, in such systems 2D structures are composed of various elements. Here, a heterostructure made of different phases of the same material is presented. Layered planar and buckled phases of silicene are prepared in a self-organization process during annealing of ultrathin layers of Au grown on Si(111) surface. Low energy electron microscopy studies show that both phases form continuous parallel layers which are twisted in respect to each other and which cover entire surface of the Au film making an ordered sheet of a size of cm2. Such heterostructures might be important for the development of new electronic and optoelectronic devices.
Biodegradable behavior and antibacterial activities of a novel Zn-0.5%Li-(Ag) alloys
Authors: Lu Yujiao , Xu Xuemei , Liu Hui , Liu Ying , Fang Hongjie , Dai Yilong , Yan Yang , Yu Kun
Published: May 2021

In this work, a novel Zn-0.5%Li-(Ag) alloys were successfully prepared by molten casting technology, and the microstructure, mechanical properties and the biodegradation behavior of Zn-based alloys in a Dulbecco’s modified Eagle’s medium (fetal bovine serum) were assessed. Additionally, their antibacterial properties were investigated by assaying the cell viability of bone marrow mesenchymal stem cells and by disc diffusion antibiotic sensitivity testing. The alloys had a reduced corrosion rate due a grain refinement effect (through more readily passivation) provided by nano-LiZn4 precipitates and Zn(OH)2/ZnO and ZnCO3 spontaneous precipitation on the surface. The Zn-0.5%Li-0.2%Ag alloy has no cytotoxicity, and which achieved highest mechanical properties ( tensile strengths of 278.3MPa and percentage elongation (ε) of 96.2%) and excellent antibacterial properties.
“A Genius without Direction”: The Abortive Exile of Dugmore Boetie and the Fate of Southern African Refugees in a Decolonizing Africa
Authors: Lawrance Benjamin N. , Kumalo Vusumuzi R.
Published: May 2021

The flight of South African writer Dugmore Boetie from his home in the Sophiatown neighborhood of Johannesburg to Dar es Salaam, Tanganyika, in mid- to late 1960 highlights the fuzzy distinction between exile and refuge before international refugee protections extended to Africa. Like many decolonial refugees after the Sharpeville Massacre, Boetie fled political persecution, lured abroad by the possibility of resettlement in London under the United Kingdom’s open-door policy to British Commonwealth citizens. Unlike many contemporaries, however, Boetie had yet to attain literary fame and had few notable advocates. Fragmentary exilic archives shift attention away from refugee reception and toward motives for flight, speaking to the ad hoc strategies of escape and survival characteristic of the transitional decolonization epoch. While networks of anticolonial, anti-apartheid sympathizers generally welcomed the first waves of exiles, politically connected socioeconomic elites were best positioned to make dangerous journeys. Men and women from all over Africa sought refuge in the 1950s and 1960s before global anti-apartheid activism was fully formed, but political subjectivities, legal statuses, and shifting citizenship statutes impeded or expedited individual paths. The better connected entered the United Kingdom, the United States, or the Soviet Union for education or employment. Those bereft of connections were forced to make a difficult choice between returning home or becoming another humanitarian statistic.
The Potential Impact of High-Risk Human Papillomavirus–Negative Cervical Intraepithelial Neoplasia 2+ on Primary Human Papillomavirus Screening
Authors: Iacobone Anna D , Bottari Fabio , Guerrieri Maria E , Vidal Urbinati Ailyn M , Ghioni Mariacristina , Spolti Noemi , Pino Ida , Passerini Rita , Di Pace Raffaela C , Franchi Dorella , Preti Eleonora P
Published: May 2021

Objectives

To investigate the prevalence of high-risk human papillomavirus (HPV)–negative cervical intraepithelial neoplasia (CIN) and invasive cervical carcinoma (ICC) and to analyze the distribution of other genotypes in this subset.

Methods

In total, 431 women who underwent excisional surgical treatment for CIN or ICC at the European Institute of Oncology, Milan, Italy, from January 2016 to December 2017 were retrospectively analyzed. The Linear Array HPV genotyping test (Roche Diagnostics) was performed on a postaliquot from high-risk-HPV–negative liquid-based cervical specimens, when available. Patient characteristics and the prevalence of high-risk-HPV–negative CIN grade 2 or worse (CIN2+) were tabulated. We used t tests to compare age between high-risk-HPV–positive and high-risk-HPV–negative patients.

Results

Overall, 8.9% of CIN2+ and 7.5% of ICC cases were high-risk HPV negative. There was no age difference between high-risk-HPV–negative CIN2+ women (mean [SD], 41.3 [8.7] years) and high-risk-HPV–positive women (mean [SD], 39.5 [9.0] years) (P = .28). The Linear Array result was available in 22 cases. Most high-risk-HPV–negative patients were positive for a single other genotype infection (32.6%). HPV 73 was the most prevalent genotype, followed by HPV 53 and HPV 84. HPV 26 was detected in 1 case of ICC.

Conclusions

Our results showed a not-negligible proportion of high-risk-HPV–negative CIN2+, suggesting that cotesting would not miss these cases.
Association Between Blood Pressure Classification Using the 2017 ACC/AHA Blood Pressure Guideline and Retinal Atherosclerosis
Authors: Matsuoka Satoshi , Kaneko Hidehiro , Yano Yuichiro , Itoh Hidetaka , Fukui Akira , Morita Kojiro , Kiriyama Hiroyuki , Kamon Tatsuya , Fujiu Katsuhito , Seki Hikari , Michihata Nobuaki , Jo Taisuke , Takeda Norifumi , Morita Hiroyuki , Nakamura Sunao , Yokoo Takashi , Nishiyama Akira , Node Koichi , Yasunaga Hideo , Komuro Issei
Published: May 2021

Background

We aimed to explore the association between the blood pressure (BP) classification defined by the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) guideline and the prevalence of retinal atherosclerosis.

Methods

This study was a retrospective observational cross-sectional analysis using the JMDC Claims Database. We analyzed 280,599 subjects not taking any antihypertensive medications. According to the 2017 ACC/AHA guideline, each subject was categorized as having normal BP (n = 159,524), elevated BP (n = 35,603), stage 1 hypertension (n = 54,795), or stage 2 hypertension (n = 30,677) using the BP value at the initial health checkup. Retinal photographs were assessed according to the Keith–Wagener–Barker system.

Results

The median age was 46 years, and 50.4% subjects were men. Retinal atherosclerosis, defined as Keith–Wagener–Barker system grade ≥1, was observed in 3.2% in normal BP, 5.2% in elevated BP, 7.7% in stage 1 hypertension, and 18.7% in stage 2 hypertension. Compared with normal BP, elevated BP (odds ratio [OR], 1.30; 95% confidence interval [CI], 1.23–1.38), stage 1 hypertension (OR, 1.71; 95% CI, 1.64–1.79), and stage 2 hypertension (OR, 4.10; 95% CI, 3.93–4.28) were associated with a higher prevalence of retinal atherosclerosis. Among 92,121 subjects without obesity, high waist circumference, diabetes mellitus, dyslipidemia, cigarette smoking, and alcohol consumption, elevated BP (OR, 1.34; 95% CI, 1.19–1.51), stage 1 hypertension (OR, 1.79; 95% CI, 1.61–1.98), and stage 2 hypertension (OR, 4.42; 95% CI, 4.00–4.92) were associated with a higher prevalence of retinal atherosclerosis. This association was observed in all subgroups stratified by age or sex.

Conclusions

Our investigation suggests that retinal atherosclerosis could start even in individuals with elevated BP and stage 1 hypertension.
Exosomal ncRNAs profiling of mycobacterial infection identified miRNA-185-5p as a novel biomarker for tuberculosis
Authors: Kaushik Aman Chandra , Wu Qiqi , Lin Li , Li Haibo , Zhao Longqi , Wen Zilu , Song Yanzheng , Wu Qihang , Wang Jin , Guo Xiaokui , Wang Hualin , Yu Xiaoli , Wei Dongqing , Zhang Shulin
Published: May 2021

Background: There are ever increasing researches implying that noncoded RNAs (ncRNAs) specifically circular RNAs (circRNAs) and microRNAs (miRNAs) in exosomes play vital roles in respiratory disease. However, the detailed mechanisms persist to be unclear in mycobacterial infection.

Methods: In order to detect circRNAs and miRNAs expression pattern and potential biological function in tuberculosis, we performed immense parallel sequencing for exosomal ncRNAs from THP-1-derived macrophages infected by Mycobacterium tuberculosis H37Ra, Mycobacterium bovis BCG and control Streptococcus pneumonia, respectively and uninfected normal cells. Besides, THP-1-derived macrophages were used to verify the validation of differential miRNAs, and monocytes from PBMCs and clinical plasma samples were used to further validate differentially expressed miR-185-5p.

Results: Many exosomal circRNAs and miRNAs associated with tuberculosis infection were recognized. Extensive enrichment analyses were performed to illustrate the major effects of altered ncRNAs expression. Moreover, the miRNA–mRNA and circRNA–miRNA networks were created and expected to reveal their interrelationship. Further, significant differentially expressed miRNAs based on Exo-BCG, Exo-Ra and Exo-Control, were evaluated, and the potential target mRNAs and function were analyzed. Eventually, miR-185-5p was collected as a promising potential biomarker for tuberculosis.

Conclusion: Our findings provide a new vision for exploring biological functions of ncRNAs in mycobacterial infection and screening novel potential biomarkers. To sum up, exosomal ncRNAs might represent useful functional biomarkers in tuberculosis pathogenesis and diagnosis.
Duality of Smell: Route-Dependent Effects on Olfactory Perception and Language
Authors: Pellegrino Robert , Hörberg Thomas , Olofsson Jonas , Luckett Curtis R
Published: May 2021

Olfactory research in humans has largely focused on odors perceived via sniffing, orthonasal olfaction, whereas odors perceived from the mouth, retronasal olfaction, are less well understood. Prior work on retronasally presented odors involves animal models and focus mainly on odor sensitivity, but little is known about retronasal olfactory perception and cognition in humans. In this study, we compared orthonasal and retronasal odor presentation routes to investigate differences in odor descriptions and evaluations. Thirty-six individuals participated in a within-subjects study using twelve odors (varying in pleasantness and edibility) in perceptual and semantic tasks. Orthonasal presentation was associated with a better ability to identify odors, and with more concrete (and source-based) language. Exploratory analyses revealed that whereas orthonasal odors were described with words that had visual associations, retronasal odors were described with words that had interoceptive associations. Interestingly, these route-dependent differences in descriptor usage were not explained by differences in sensitivity and intensity, suggesting instead a cognitive and linguistic processing difference between odors presented orthonasally and retronasally. Our results indicate that olfaction is, in fact, a dual sense, in which the routes change the perception of an odor.