Graphene has emerged as the most popular topic in the active research field since graphene's discovery in 2004 by Andrei Geim and Kostya Novoselov. Since then, graphene research has exponentially ...accelerated because of its extraordinary properties, which have attracted the interest of researchers all over the world. For example, among the key properties are its thermal conductivity, electrical conductivity, optical transparency, and mechanical properties. These remarkable properties of graphene show its promise for applications in different industries including optical electronics, photovoltaic systems and others. However, the large-scale production and transfer method onto target substrates of monolayer graphene for commercial and industrial applications are still under study in the improvement stage. Therefore, this review presents the state-of-the-art research activities and latest advancement in the synthesis of graphene using various carbon precursors including solid, liquid and gas carbon feedstocks. The characterization methods have also been critically discussed in this review. In addition, the advancement in the transfer methods onto target substrates for achieving clean and high-quality transferred graphene have been thoroughly reviewed. Furthermore, the current growth mechanisms of single and multilayer graphene have also been discussed.
Graphene has emerged as the most popular topic in the active research field since graphene's discovery in 2004 by Andrei Geim and Kostya Novoselov.
Abstract Climate change has been a huge issue. Some studies found that climate change affects many sectors, including agriculture. Meanwhile, not all farmers know that climate change exists, which ...might affect their agricultural activities. This study explores farmers’ perception of climate change in Tulung Sub-district, Klaten Regency, Central Java, Indonesia. The primary data were obtained using a close-ended questionnaire that covers 101 farmers. The results revealed that most farmers are aware of climate change. The 99% of farmers recognize that the air temperature is becoming warmer. Furthermore, 91 respondents answered that the seasons were unpredictable, and 62 respondents had noticed a water irrigation reduction A 79.2% of farmers agreed that crop failure is caused by climate change if there is no early mitigation. Then, 52 respondents stated that the long-term use of chemical pesticides causes environmental damage.
Stingray provide a high economic contribution and increase in production and utilization. Conservation effort needed to identify molecularly using CO1 gene. The success of CO1 gene in identifying ...species can not be separated from amplification in polymerase chain reaction (PCR) technique. The use of primer FishF1, FishR1, FishF2, and FishR2 to amplify COI gene for stingray traded at fish auction Tasik Agung Rembang never been done, so it need to be researched. The purpose of this study is to amplify the COI gene of stingray traded at fish auction Tasik Agung Rembang using two pairs of primers. Five stingrays sample were obtained from fish auction Tasik Agung Rembang. Then its DNA was isolated using protocol from TIANamp Marine Animals DNA Kit and measured in quantity using nano spectrophotometer. Amplification of CO1 gene by PCR technique. Based on the results of the study showed that the five samples had good DNA purity, concentration, and quality. The 5 samples amplification result showed that the FishF1-FishR1 primer pair succeeded in amplifying samples a, b, d, and e, while the FishF2-FishR2 primer pair succeeded in amplifying samples b, c, d, and e with a PCR product length around 655 bp.
The ability of literacy and statistical reasoning is very important for the students of sport education college due to the materials of statistical learning can be taken from their many activities ...such as sport competition, the result of test and measurement, predicting achievement based on training, finding connection among variables, and others. This research tries to describe the sport education college students' ability of literacy and statistical reasoning related to the identification of data type, probability, table interpretation, description and explanation by using bar or pie graphic, explanation of variability, interpretation, the calculation and explanation of mean, median, and mode through an instrument. This instrument is tested to 50 college students majoring in sport resulting only 26% of all students have the ability above 30% while others still below 30%. Observing from all subjects; 56% of students have the ability of identification data classification, 49% of students have the ability to read, display and interpret table through graphic, 27% students have the ability in probability, 33% students have the ability to describe variability, and 16.32% students have the ability to read, count and describe mean, median and mode. The result of this research shows that the sport students' ability of literacy and statistical reasoning has not been adequate and students' statistical study has not reached comprehending concept, literary ability trining and statistical rasoning, so it is critical to increase the sport students' ability of literacy and statistical reasoning
In recent years, the environmental pollution of microplastics (MPs) has increasingly drawn our attention. MPs are small fragments of plastics that are commonly dispersed in the environment. The ...accumulation of environmental MPs is due to population growth and urbanization, while natural disasters such as hurricanes, flooding and human activity may influence their distribution. The leaching of chemicals from MPs raises a significant safety problem and environmental approaches aimed at reducing the use and recycling of plastics, with the replacement by bioplastics and wastewater treatment developments are called for. This summary also helps in demonstrating the connection between terrestrial and freshwater MPs and wastewater treatment plants as the major contributors to environmental MPs by discharges of sludge and effluent. More research on the classification, detection, characterization and toxicity of MPs are essential to enable greater options and solutions. Control initiatives need to intensify the comprehensive study of MP waste control and management information programmes in the fields of institutional engagement, technological research and development, legislation and regulation. A comprehensive quantitative analysis approach for MPs should be created in the future, and more reliable traceability analysis methods should be built to examine further its environmental activity and existence, where this should be done to improve scientific research on MP pollution in terrestrial, freshwater and marine environments and hence, develop more scientific and rational control policies.
Technology has become a major component in every aspect of human life, and learning resources had included in that aspect. This issue described media for learning the "Jaman-Now App Permilang (JNAP)" ...can have an effect on students' cognitive and their motivation in the learning process. The quantitative approach was the method used in this study, where this research was a part of the development research conducted by researchers, in which this research presentation specifically explained aspects of the effectiveness of the product being developed. Product feasibility tests are carried out in the school environment through two processes (limited & extensive test). Those processes were used with observation, testing, and questionnaire techniques as a measure of product success. The feasibility of this research focused on the effectiveness of the product in chemical learning where this effectiveness is assessed as an indicator of product feasibility with a valid instrument (cognitive tests, questionnaire). Statistical data revealed that the average N-Gain in the 1st process has a point of 0.25 (low), the 2nd process was 0.42 (medium), and very good criteria for the motivation aspect. The results indicated that the product has a good enough impact on the co-positivity and motivation of students, although the visualization of the values shown in the medium criteria. In other words, the product has the potential to become one of the strategies in improving the quality of chemical learning, assessment for chemistry learning, strengthening their cognitive, and guidelines for students in reflecting themselves in an understanding of the chemical material.
Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb). TB prevention is done through vaccination using the Bacille Calmette-Guerin (BCG) vaccine. There are weaknesses ...in this vaccine, so research is still needed in the search for specific antigens. One potential is the Rv3204 gene that encodes the methylated DNA-protein cycteine methyltransferase protein 11 kDa (MTSP11). This protein is immunogenic because it can produce interferon-γ (IFN-γ). The purpose of this study was to isolate and clone the Rv3204 Mycobacterium tuberculosis into Escherichia coli BL21 as vaccine tuberculosis. The research stage was amplification of Rv3204, ligation to pQE-30 Xa expression vector and transformation to Escherichia coli BL21 host cells on LB medium. Characterization was carried out by PCR analysis to recombinant plasmid isolation. The results showed that Rv3204 encoding MTSP11 was successfully cloned to E. coli BL21 with white colony formation and characterization showed that the band was 306 bp as the Rv3204 gene.
Abstract
This research aims to produce an electronic module with scientific literacy through direct instruction on impulse and momentum materials and describe its feasibility. The specific objective ...of this study is to describe the validity, practicality and effectiveness of the electronic module. The research method used is research and development using the ADDIE model (Analyze, Design, Develop, Implement, Evaluate). The test subjects in this study were ten students at one of the senior high schools in Banjarmasin. The data were obtained through the electronic module validity sheet instrument, student response questionnaire sheets, and student learning outcomes tests. The results show that: (1) the electronic module is declared valid with a very high category, (2) the electronic module is declared practical in the good category, (3) the electronic module is declared effective with a gain score of 0.64 in the moderate category. In this study, it can be concluded that the electronic module with scientific literacy through direct instruction on impulse and momentum material is declared fit for use in learning.
Abstract
Literature study of fraction learning problem in mathematics and scaffolding strategies, aims to reveal the results of previous research and offer solutions to solve the problem through ...scaffolding. This literature studies are sourced from the IOP conference series journal, science direct, and springer link journal articles, to expand the study taken from other sources, both journal articles and source books. The basis of the scaffolding theory refers to Vygotsky’s opinion which includes two main ideas, namely the zone of proximal development (ZPD) and scaffolding. The conclusions from the literature study are; (1) difficulties in understanding the concept and fraction calculation operations in mathematics experienced by elementary school students, junior high school students, and primary school teacher education students, (2) to help overcome difficulties understanding fraction concepts and fraction calculation operations, it is necessary to provide learning time according to student needs until achieving a complete understanding, (3) solutions to help learning fractions concepts and fraction calculation operations can be pursued through the ZPD scaffolding strategy by combining teacher-student dialogical interactions, collaborative, contextual, enriching metaphors, and dynamic communication.
Peternakan ruminansia merupakan sektor yang sangat penting dalam menyediakan sumber protein hewani. Namun seiring perkembangannya mendapat beberapa kendala terkait dengan produksi metan dari ternak ...ruminansia yang berdampak negatifbagi penurunan produktivitas ternak dan lingkungan (akumulasi gas rumah kaca yang berdampak pada pemanasan global). Salah satu upaya dalam menurunkan produksi metan ternakruminansia yaitu dengan menggunakan senyawa metabolis sekunder dari tanaman berupa tanin dan saponin. Banyak penelitian yang sudah dilakukan dengan memanfaatkan senyawa metabolit ini. Sehingga tulisan ini bertujuan untuk mereview tentang hasil berbagai penelitian terkait pemanfaatan senyawa bioaktif tanaman (tanin dan saponin) terhadap produksi metan ternak ruminansia. Dari hasil review beberapa jurnal penelitian dapat disimpulkan bahwa senyawa bioaktif tanin dan saponin dapat dimanfaatkan dalam rangka menurunkan emisi metan, meningkatkan efisiensi pakan serta aman bagi ternak dan lingkungan. Penambahan tanin dan saponin secara in vitro dan in vivo memberikan respon yang berbeda-beda terhadap produksi metan. Hal ini terkait dengan kandungan, level serta bentuk tanin dan saponin yang diberikan. Penambahan tanin dan saponin pada dosis yang optimal mampu menurunkan produksi metan, populasi metanogan dan populasi protozoa, serta meningkatkan produksi VFA total dan parsial (terutama propionat), populasi bakteri rumen dan tidak mengganggu kecernaan bahan pakan. Kata kunci : metan, ruminansia, saponin, tanin
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