Search

High Early Strength Concrete (HESC) is one type of high-performance concrete. HESC production requires high-quality materials and additives, namely chemical admixture type C (superplasticizer) to get high performance. This study aims to obtain a HESC mix design using a superplasticizer with the best performance. The 3 variations of HESC are made by adding a superplasticizer to a mixed concrete with the same dosage but from 3 different manufacturers, namely HESC-1, HESC-2, and HESC-3. Specimens performance consisted of tests for both fresh concrete and hardened concrete. The fresh concrete was tested by the slump, and the hardened concrete was tested by density and compressive strength tested at the age of 12 hours, 14 hours, and 3 days on cylindrical specimens measuring 100 mm x 200 mm which have been cured by water curing. Based on the test results, it was found that the average slump values in HESC-1, HESC-2, and HESC-2 were (cm): 64.0, 69.5, and 70.5. This shows that all HESC specimens are categorized as Self Compacting Concrete. According to the results of the density test on all specimens ranging from 2382 to 2436 kg/m3, all specimens are included in normal-weight concrete. With the initial compressive strength value of HESC at the age of 14 hours in the range of 21.0 to 24.9 Mpa, it can be concluded that all HESC specimens meet the requirements of High Early Strength Concrete, where HESC-3 is the best performance one.

Nitrogen (N) degrading bacterias are needed for the control of fish culture organic waste. The purpose of the study was to evaluate N- degrading bacterias on survival, growth performance, blood profil, and media water quality for glass eel culture. Twelve aquaria were used at rate of 20 fish/L water. Artemia sp and peleted diet were fed at satiation on test fish for 60 days of experimental period. Completely randomized design with 4 treatments and 3 replications were used. The treatments were different N- degrading bacterias, namely: A) no bacteria (control); B) Nitrobacter sp, C) Pseudomonas sp, and D) Bacillus sp. The parameters tested were survival rate, absolute growth and length, blood profil, and water quality. The results showed that Bacillus sp was the best bacteria for degrading nitrogen to produce the best values of survival rate (90.62±0.40%), total length (9.31±0.59 cm), body weight (1.04±0.17 g/fish), total erythrocytes (1.04×106–1.10×106 cells/mm³) and total leukocytes (7.61×106–8.85×106 cells/mm³). Nitrite, nitrate, ammonia concentrations in culture added bacterias were relatively stable and lower than those at control. It could be stated that adding Bacillus sp can improve survival, growth performance, and blood profil as well as uphold water quality in optimal range conditions.

Diarrheal diseases are the second cause of the high morbidity and mortality in children under five years old. According to the Basic Health Survey 2018 conducted by the Ministry of Health, the prevalence of diarrheal diseases among children under five years old that were diagnosed by healthcare workers was 11.0%. The aim of this study was to describe the enteric pathogen isolated from children with diarrhea. The study was conducted in five cities in Indonesia: Jakarta, Serang, Denpasar, Makassar, and Mataram. The Inclusion criteria were children aged one month to five years old, with diarrhea that was diagnosed by a healthcare worker. The rectal swabs were sent to the Centre for Research and Development for Biomedical and Basic Health Technology, National Institute of Health Research and Development, Ministry of Health in Jakarta. Virus and Enterotoxigenic Escherichia coli (ETEC) identification by using multiplex PCR from Seegene, meanwhile bacteria identified by conventional method. As many as 2626 children under five years old participated in this study. The highest viral pathogen that causes diarrhea is viral 1.807 (68,81%) and 486 (18,56%). The virus etiology was Rotavirus 982 (54,34%) cases, followed by Adenovirus 916 (50.69) cases, Norovirus II 444 (24,57%) cases, meanwhile the bacteria pathogen were Enterotoxigenic Escherichia coli detected in 262 (9,98%) followed by Campylobacter jejuni and Shigella spp. This study described Rotavirus is the prevalence etiology of diarrhea among children under five years old followed by Adenovirus and Norovirus, some other cases reported the cause of diarrhea were bacteria ETEC E. coli followed Campylobacter jejuni, Shigella spp, etc.

For different bacterial preservation techniques, there is no single method applicable for all bacteria. This study aimed to assess the viability of seven species/species groups of clinical bacteria isolates on the long-term storage (more than 5 years) by using Tryptic Soy Broth with 15% glycerol in the deep freezer (-70 to -80°C). A total 10,654 clinical bacteria isolates used as samples in this study. The isolates consisted of seven species/species groups (i.e. Escherichia coli, Campylobacter spp, Shigella spp, Vibrio spp, Salmonella spp, Aeromonas hydrophila, and Neisseria gonorhoeae). The isolates were collected from some previous studies and preserved in the Tryptic Soy Broth (TSB) with 15% glycerol and stored in the deep freezer (-70 to -80°C) for more than five years. The samples were revived on the suitable medium to evaluate the viability of bacteria. Identification conducted by microscopic examination, biochemical test, and latex agglutination. The study showed that the viability of Salmonella spp, Shigella spp, Aeromonas hydrophila and E. coli was 100%, while Campylobacter spp, Vibrio spp, and N. gonorhoeae were 66.7%, 66.4%, and 52.5% respectively. We concluded that viability of Salmonella spp, Shigella spp, A. hydrophila, and E. coli was optimum thus better than Campylobacter spp, Vibrio spp, and N. gonorhoeae for more than 5 years storage by using TSB with 15% glycerol in the deep freezer (-70 to -80 °C).

Indonesia is one of the five countries with highest diphtheria cases in the world. Laboratory confirmation by culture method as a gold standard requires bacterial survival. Indonesia’s geographical condition as an archipelagic country and difficulties in transporting clinical samples are often obstacles in maintaining bacterial survival. This study aims to evaluate the ability of several transport mediums to maintain the survival of Corynebacterium diphtheriae. A total of 90 isolates were divided into nine groups of transport mediums. Samples were divided into 2 treatment groups, namely room temperature and temperature 2-8 ºC. On day 2, 4, 8, 16, and 32, 1 isolate from each group with 2 different incubation temperatures was cultured on blood agar medium and incubated for 24 hours at 37 ºC. Bacterial survival was indicated by the growth of suspect colonies which were identified by microscopic and biochemical tests. Results show serum with tellurite can be used with viability lower than silica gel, but higher than other media. Meanwhile at a temperature of 2-8 ºC, there are 2 types of the best transport medium, namely serum with tellurite and open silica gel in aluminum foil. Newborn Calf Serum supplemented with Tellurite can be used as an alternative transport medium for Corynebacterium diphtheriae, both at room temperature and at 2-8 ºC.

Students perceive physics as a difficult subject to understand because the material contains a lot of formulas, mathematical calculations, and abstract concepts. One of the physics materials for high school students in Newton’s law. Newton’s law is one of the materials considered difficult to understand by students because the basic concepts in Newton’s law material, namely the concept of force have not been fully mastered by students, resulting in students’ cognitive physics abilities that are still low and have not reached the minimum completeness criteria (KKM). This study aims to examine the role of the digital module in improving students’ cognitive abilities in Newton’s Law material. The research subjects were 108 students of class X MIA in 3 high schools in the Surakarta residency. The study used a quantitative descriptive method with a test technique using 20 multiple choice questions about Newton’s Law. Data were analyzed using N-gain. The results showed that the average scores before using the digital module at 3 SMA in Surakarta residency were 53, 58, and 60 respectively, while the average scores after using the digital module were 73, 74, and 75. Based on the N gain value, the increase in ability students’ cognitive belonged to the medium category, namely > 0.3. The digital module has a significant effect on improving students’ cognitive abilities in Newton’s Law material.

In this work, citronella oil’s activity as a natural coating for antifungal on mahogany’s surface morphology(Swietenia mahagoni)leaves waste as composite was investigated. The composite material from mahogany leaves requires a coating that can inhibit fungi growth. Citronella oil was a natural material that can be used as an antifungal for coating this composite. The concentration of citronella oil used for the MIC (Minimum Inhibitory Concentration) assay was 0.1-2.0%. Based on the MIC of citronella oil can inhibit the growth of the fungusPleurotus ostreatusat the optimum concentration of 0.2% with inhibition of 33.33%. Coating of citronella oil on composites using several concentrations ranging from 0.0, 0.4, 0.8, 1.2, 1.6 and 2%, respectively. The surface morphology on composite with citronella oil as the natural coating was observed using a CCD camera microscope with a magnification of 50x showed that the growth of fungal spores on the composite surface began to be inhibited a concentration of 0.4%. This surface morphology of composite can prove that citronella oil can be used as an antifungal.

Thinking ability is a basic thing that every student has. Concrete and Abstract thinking abilities are part of the cognitive development stage. This study aimed to identify the correlation between concrete and abstract thinking abilities with cognitive learning outcomes. This study design was a non-experimental correlation in quantitative research. All 7th-grade students of SMPN 2 Surakarta in the 2019/2020 academic year were used as subject in this study. One sample class was selected using Cluster Random Sampling. Data on thinking ability and cognitive learning outcomes were collected using an online test method via a google form. The analysis techniques were correlation product moment on SPSS and scalogram on Rasch Model Analysis. This study found that there is a positive correlation between concrete and abstract thinking abilities with cognitive learning outcomes, students who dominate the abstract thinking abilities have better learning outcomes than the student who dominates the concrete thinking abilities.

So many jobs today require high-level skills, logical thinking, creative thinking, generic and scientific processes, being able to solve problems, and make decisions. These skills are one of the main goals of 21st-century learning. Based on the results of a survey by TIMSS (Third International in Mathematics and Science Study) students in Indonesia in the field of science are ranked 38 out of 40 countries. This study aims to describe the generic science skill profile of YPPK Teruna Bakti high school students class XI on momentum and impulse. The method used in this research is descriptive quantitative. Data were collected through a test method in the form of multiple-choice questions based on three of the nine generic science skills indicators according to Brotosiswoyo. The test was conducted on 35 students. The test results showed that the overall average level of mastery was 55.7%. Generic science skills per indicator, for direct observation indicators 59.5%, concept building indicators 55.7%, logical consistency indicators 51.4%. The overall average for the concept of momentum and impulse is 60%, the concept of momentum-impulse relationship and the law of conservation of momentum is 52%, and the concept of collision and application impulse-momentum is 55%.

Discovery learning is an alternative learning model that can improve the science learning process. Discovery learning research has developed rapidly in recent years. Discovery learning research has produced many theoretical and empirical findings. Many trends and problems have emerged, highlighting the complexities and dynamics of research in discovery learning. Therefore, this study aims to determine current trends regarding discovery learning. This study used a bibliometric analysis approach based on the Scopus database. Based on the title, abstract, and keywords, this research succeeded in obtaining 634 documents from 2015 to 2019 for further study. This study uses bibliometric standards as a measure to report research results such as year of publication, country/territory of publication, type of document, type of source, subject area, author, affiliation, keyword analysis, and author collaboration analysis. The results showed that the publication of discovery learning has increased significantly since 2015, although it had decreased in 2017. The increase in the number of discovery learning research shows the importance of applying discovery learning in the learning process. The implications of this research for the development of discovery learning in a variety of frameworks, although much discovery learning research has been conducted.

Snakehead (Chana striata) has a strategic position in contributing to the national economy due to its albumin content which has been proven to have been used as biopharmaceutical for postoperative treatment. This has led to an increase in the exploitation of snakehead in nature which has depressed its population. The snakehead culture is the right step in supplying material demanded for biopharmaceutical industries. The success of the development of this snakehead culture requires support, among others, of the availability of sufficient seeds in number and time as well. This paper, therefore, discussed the strategy to develop seed mass production of snakehead in a controlled condition in Indonesia. The method used was a desk study, collecting published papers and personal observations related to snakehead hatchery. The data were analysed descriptively. The results of the study indicated that the bio-reproduction information of snakehead in nature can be used as a reference in the process of brood-stock management and larval culture under controlled conditions. Commercial and / or home-made fish diet containing protein of 38–42% can ripen gonads and spawn snakehead brooder using hormone stimulation in a hatchery. Water sources can use ground water and / or pipe that has been previously treated, especially setting the pH, alkalinity, hardness, and water temperature. Proper feeding strategies can increase the growth and production of snakehead fish seeds. This snakehead hatchery can be done both inside and outside its habitat.

Analytical thinking skills are part of critical thinking skills and higher-order thinking skills that are the demands of students in the 21st century. This study aims to produce a conceptual framework for a model in science learning to empower students’ analytical thinking skills. The method used in this study was a qualitative method, with the primary source was literature review. Data collection techniques employed literature study which collected data through books and journals. The data obtained from the literature were collected and processed by editing, organizing, and finding the results. Data analysis in this research was content analysis to analyze in-depth the contents of the literature being studied. The results of this study consisted of: 1) The conceptual framework of the modified science learning model is called the problem and research-based learning (PRBL) model, 2) The modified PRBL model has the potential to empower students’ analytical thinking skills. This study illustrates to lecturers and subsequent researchers that the modified PRBL model demonstrates the potential to empower analytical thinking skills. The researcher suggests the next researchers conduct research on the application of the PRBL model in the field to test the validity and practicality of the model.

Bio-oil produced from biomass pyrolysis is still acidic and has a low heating value. Co-pyrolysis is a process of pyrolysis of biomass and material that has a higher (H/C) effective. Low-density polyethylene (LDPE) is a type of plastic waste that has a higher hydrogen index than empty fruit bunch (EFB). To improve the quality of bio-oil, it is necessary to co-pyrolysis EFB and LDPE using a calcium oxide catalyst. The purpose of this research is to produce bio-oil from a mixture of EFB and LDPE, to determine the effect of the CaO catalyst ratio and temperature on the bio-oil yield, and to determine the physical and chemical characteristics of the bio-oil product. The catalytic co-pyrolysis process uses 10 grams of EFB/LDPE mixture (EFB/LDPE ratio 50%:50%), CaO catalyst with a variation of CaO/raw material ratio (1%, 2%, 3%, 4%, and 5% w/w) and temperature variations (400°C, 450°C, 500°C,550 and 600 °C), with nitrogen gas flowing at a flow rate of 400 mL/min for 45 minutes. The highest yield generated on the use of CaO/raw material ratio of 5% w/w and temperature of 550 °C was 35.2%. The characteristics of the bio-oil obtained were the density of 0.948 g/mL, the viscosity of 4.18 cSt, pH of 4.04, and heating value of 43.4 MJ/Kg. The results of GC-MS analysis showed that bio-oil contained 37.05% phenol compounds, 27.88% hydrocarbon, 20.27% ketones, 7.21% alcohol, 4.36% aldehydes, and 1.08% ester.

Air pollution (O3, SO2, CO, NOx, PM, and Pb) can have a severe impact on environmental damage and human health problems. Therefore, monitoring of pollutant levels in the air is essential to find out how much that gas levels can cause air pollution. In general, air quality monitoring is carried out using a conventional system. Inside the system requires large-sized equipment, long time for analysis, expensive, and with limited space resolution. It becomes inefficient, amid the development of technology that can carry out online monitoring, real-time, low cost, small size and a wide range of distance. The technology is known as the wireless sensor network system. The aim of this research is to design an air quality monitoring system using a Wireless Sensor Network (WSN) that can be accessed via the web and smartphone. The developing of WSN systems consist of two steps, are design and implementation device. The first step is done by assembling sensor nodes and hosting a web server. And after the device was finished, the next step is testing and calibrating of the system. The results of experiment show that the system is able to detect various air pollution, such as SO2, NOX, CO, and other environmental factors such as temperature, humidity and wind speed.

Corporate farming is farmland merger activity jointly organized by farmers in an integrated single management. This system can be a solution for many of the problems faced by farmers today. Business efficiency, quality standardization, and effectiveness and efficiency in managing the utilization of resources are expected when the company’s agricultural system is implemented. Paddy farming in Central Java is still dominated by narrow-scale farming activities that are managed individually. This results in diverse productivity and is economically less efficient, resulting in low competitiveness. Farming activities currently carried out by farmers will be more efficient if managed by implementing a corporate farming system and supported by the Warehouse Receipt Integrated System makes microfinance institutions interested in distributing funds to capital farmers. The warehouse receipt system is supported by the concept of comparative agriculture, it is hoped that the synergy of both can increase the capital and income of farmers in Central Java.

Creativity is one of some competencies needed in the 21st Century, therefore creativity is something that people should have to face challenges in the 21st Century. The aim of this research was to 1) find the creativity’s level which measured based on aspects Fluency, Flexibility, Elaboration, Originality, and Problem Solving; 2) find the percentage of each creativity’s indicators. This research was held in SMP Negeri 1 Kawedanan Magetan on second semester 2017/2018. This research’s subject were 55 7th grade students, determined with the random sampling technique. This research was descriptive quantitative research. Data were collected using observation technique. Analysis technique of observation sheet with quantitative analysis. The outcomes showed that: 1) student’s creativity in the high level was 31, in the medium level were 17, in the low level were 7; 2) the percentage of each creativity’s indicators in Fluency 74.55%, Flexibility 78.64%, Elaboration 77.42%, Originality 87.73%, and Problem Solving 88.41%. The conclusion was the level of student’s creativity on Science learning was at high level seen on each aspect which gets the result over 50%. Creativity analysis in this research can be used as a reference for further research about measuring deeper creativity.

Students’ argumentation skills both in the learning process and assessment to realize the transformation of the production of quality claim and warrant are very important to be implemented. This study is trying to analyze the process of students’ argumentation skills transformation through a contextual physics learning strategy called “Claim and Warrant”. This study used descriptive survey method with eleven grade student in Bandar Lampung as the population. Beside that, cluster random sampling technique was used to specify the sample. A complex problems as an exercise were given to thirty two senior high school students in order to produce alternative statements and the basis of theoretical-evidence relations. The data were obtained through reasoned multiple choice tests with feedback andanalyzed through a feedback-assessment process. The results showed the increasing of students’ argumentation skills in form of production of alternative statements and counter.

This study aims to measure students’ critical thinking skills through the ability to make practical work reports. The method used is qualitative descriptive method in the form of critical thinking skills through assessment of student work reports and questionnaire data. Rubric that used to measure students’ critical thinking skills with 10 indicators: clarity, accuracy, precision, consistency, relevance, strength, reason, depth, breadth and fairness. The study sample was 34 students. The results showed that students’ critical thinking skills through work reports were still 17.6% of students already had very high critical thinking skills, 58.82% had moderate critical thinking skills and as many as 23.53% students have weak critical thinking skills. Students have a high category in the breadth. Then clarity, accuracy, precision, consistency, and relevance have a moderate and evidence has a weak. The results of the student and teacher questionnaires about the application of practicum also stated that before practicum students were still sometimes given time to conduct preliminary studies.

A quartz reinforced polyvinyl acetate/leaves-waste composite has been made using simple pressing method. This work was performed as an answer for the solid waste abundance and deforestation activity. Having been wet-milled using ethanol 70% and dried for 4 days, the quartz was added as reinforcement in polyvinyl acetate (PVAc)/leaves waste mixture with varied contents to form PVAc/leaves waste/quartz composite via pressing at 5 metric ton for 20 minutes. The compressive strength test shows the mechanical strength varies from 35.53 to 39.93 MPA as quartz contents, with a sample having quartz sand content 4.60 × 10−3 (w/w) has maximum mechanical strength as 39.93 MPa, and the addition of quartz above the content makes the mechanical strength tends to decrease. The strength values are comparable to some previous works by several authors and some building materials, such Sago pulp composite, polyurethane/solid waste/nanosilica composite, agriculture-waste/silica composite, soil brick, limestone, natural fiber reinforced concrete and Portland cement concrete. This result shows the quartz reinforced polyvinyl acetate/leaves-waste composite has been acceptable to compete the woods as building materials to reduce deforestation.

This research aimed to find out the effect of high and low creativity on the students’ learning achievement. This research was conducted at MTs Negeri 2 Surakarta 2017/2018 Academic Year. The research method used was experimental research. The sampling was done using simple random sampling technique. The data were collected using multiple choice objective test to obtain the learning achievement data in the Structure and Earth Layer topic and observation sheet to obtain creativity data. The data analysis used was parametric statistical test with one-way ANOVA test. Based on the statistical analysis performed, it was obtained that the sig. value was 0.000. Because the sig. value is < 0.05, it can be concluded that Ho is rejected. This shows that high and low creativity has an effect on the students’ learning achievement in the Structure and Earth Layer topic. The result indicates that students who have high creativity have higher learning achievement.

We developed a TPACK based-physics learning media. This development was using 4D methods. Researchers analysed the need for learning media that can improve students’ critical thinking skills with technological offerings. This research took place in SMA ABBS Surakarta. The research subjects were three senior high school physics teachers and fifty-one students. We observed the facilities of the school then concluded that the facilities supported TPACK based learning activity. We also gave the questionnaire to teachers about the learning activity. The data gathering was carried out using observation rubric, students’ worksheets, presentation scoring rubrics, report scoring rubrics, and two tiers multiple-choice test instrument on critical thinking skills. Two lecturers, two physics teachers, and two peer reviewers validated the media. Then it tried out in the small group. In the big group, the media is proven could develop critical thinking skills with the difference between pre-test and post-test results were significant.

This study aimed to analyze the ability of students to think in critically analytical and evaluative ways on chapter of motion of objects and living things. The object of the study was 280 students of 8th grade of MTs Negeri 1 Wonogiri in the academic year 2019/2020. This study used descriptive qualitative method to describe students’ critical thinking skills. Data was collected using reasoned multiple choice test which was developed based on skills of critical thinking according to Facione’s theory. As a result, it can be concluded that the criteria of the analysis and inference ability of the students were lack. While the ability of interpretation, evaluation, explanation, and self-regulation were in the very lack criteria.

Physics has the character of logical thinking. The use of technology in physics learning encounters the problem. The purpose of this study is to evaluate students logical thinking ability and determine a physics learning strategy to improve students logical thinking ability. The subjects of this study were 81 Islamic boarding school students in Ponorogo. The research approach was used mix method. Instrument test research was used by giving Tests of Logical Thinking (TOLT) which developed by Tobin and Capie. Instrument test contains 10 questions that depict probabilistic reasoning, controlling variable, proportional reasoning, correlational reasoning, and combinatorial reasoning. The results show that the average students logical thinking ability occupies a level of concrete thinking with a score of 1,36. This finding describes the logical thinking ability was still being the lowest level. Therefore, alternative learning such as integrating with technology is necessary to improve the logical thinking ability of students. Integrating learning with technology can be done by TPACK model.

Heavy physical exercise causes increased production of free radicals. The accumulation of oxidative stress can reduce cardiorespiratory endurance. VO2max plays a role as an indicator of the circumstances of cardiorespiratory. An increase in cholesterol levels is a risk factor for coronary heart disease. As a result, there is a decrease in fitness marked by a decrease in the value of VO2max. The purpose of this study was to determine whether the antioxidant supplement given during heavy physical exercise had a beneficial effect on decrease cholesterol and the increase of VO2max levels. The subjects were 30 students, male sex, 20-22 years old, divided into 3 groups randomly, each 10 people, group 1: subjects not given heavy physical exercise and only given a placebo (control); group 2: subjects given heavy physical exercise and placebo (HPE-RDF); group 3: subjects given heavy physical exercise and red dragon fruit juice (HPE+RDF). Measurement of cholesterol and VO2max levels in the pre-test and post-test. The results showed that there was an increase in VO2max and a decrease in cholesterol (p2max and reduce cholesterol levels.

The purpose of this study is to determine the initial characteristics of foam concrete mixtures. This performance, using Ordinary Portland Cement (OPC) and Portland Composite Cement (PPC) were examined for its density and compressive strength on day 1, 3 and 7. In addition, the production process was initiated by formulating a mix of foam solvent, simultaneously creating the mortar, with the use of OPC or PPC, followed by the individual integration of a foaming solvent. Furthermore, after density evaluation, a specimen is produced with the cylinder cast, in a diameter of about 150 mm, and length of 300 mm, containing individual water and atmosphere curing. The density obtained was higher than the outcome of air curing tests, which decreased continuously with the concrete age. Furthermore, the compressive strength measured was relatively lower in water curing testing, using PCC, and on day 7it w was up to 3.46 MPa, or 73.5%, which seems to be lower than the record obtained with the use of OPC, which was about 3.94 MPa. At similar age, the value obtained for air curing with PCC reached 4.52 MPa or 96.0%, exhibiting a lesser value than OPC (4.71 MPa).

21st-century physics learning challenges teachers to teach physics that not only memorizes formulas, but is able to improve scientific attitudes and higher order thinking skills (HOTS). Technological, pedagogical, and content knowledge (TPACK) concept is considered capable of presenting this goal with technology integration. Researchers developed TPACK-based learning media that can improve HOTS and scientific attitudes using spreadsheet macros. This study uses the Define, Design, Develop, and Disseminate (4D) method. Media products have been proven to be able to develop HOTS and scientific attitude as seen from the value of N-gain in the medium category with score of 4 for HOTS and 6 for scientific attitude.