ABSTRAKDaun Buas-buas (Premna serratifolia Linn) dipercaya oleh masyarakat dapat menurunkan kolesterol solusi obat herbal alternatif ditengah mahal dan efek samping buruk yang ditimbulkan obat sintetik. Penelitian dilakukan dengan tahapan daun Buas-buas (Premna cordiflora Linn) dikeringkan, dihaluskan dan dimaserasi menggunakan etanol, kloroform, dan n-heksan. Ekstrak yang diperoleh dari evaporasi, ditimbang dan disimpan dalam desikator. Uji aktivitas antikolesterol secara In Vitro dimulai dengan penentuan panjang gelombang maksimum larutan baku kolesterol dengan spektrofotometer UV-Visible. Dilanjutkan dengan pembuatan kurva standart dengan konsentrasi larutan kolesterol 0.5; 0,75; 1; 1,25; dan 1,5 mL larutan kolesterol 1000 ppm ditambahkan etanol 95% hingga volume 5 mL serta diukur absorbansinya. Pengukuran kadar koleterol setalah diberikan ekstrak etanol, kloroform, dan n-heksan daun Buas-buas dengan cara 0,5; 1; 1,5; 2; dan 2,5 mL ditambahkan 5 mL larutan kolesterol dengan konsentrasi 100 ppm. Selanjutnya diukur absorbansi pada panjang gelombang maksimum yang diperoleh pada panjang gelombang maksimum kolesterol. Hasil penelitian menunjukkan ekstraksi dengan pelarut etanol menghasilkan rendemen terbanyak. Ekstrak Premna serratifolia Linn dapat berfungsi sebagai anti kolesterol. Penurunan absorbansi larutan standar kolesterol 100 ppm terdapat pada penmbahan 0,5 mL ekstrak kloroform. ABSTRACTPremna Serratifolia Linn is believed to reduce cholesterol and as an alternative herbal medicine solution among the cost of medicine and the side effects caused by synthetic drugs. This study was conducted in several phases by using Premna Serratifolia Linn which was drained, mashed, and macerated using ethanol, choloform, and n-heksane. Extract obtained from evaporation, then whighed, and stored in a desiccators. Anti-cholesterol activity was tested test by using in vitro : began with determination of the maximum wavelength of the cholesterol standard solution with a UV-Vis spectrophotometer and continued by manufacturing the standard curve with the cholesterol concentration of 0.5; 0.75; 1; 1.25; and 1.5 mL and 1000 ppm cholesterol solution. Furthermore, maximum absorbance wavelength was measured in order to obtain the maximum wavelength of the cholesterol. The study reveled that the solvent extraction of ethanol produced the largest rendement. The extract Premna Serratifolia Linn is functioned as an anti-cholesterol. In addition, the absorbed reduction of 100 ppm cholesterol standard solution found in the addition of 0.5 mL choloform extract.
Evaluation tools used in schools were still classified as conventional so that they had weaknesses, including the old assessment process and during the evaluation activities were less effective. Therefore, it needed an interactive evaluation tool and habituation for students in Computer-Based National Exam. The purpose of this research was to produce evaluation tool based on wondershare quiz creator for class XI on material about colloid in SMA Koperasi Pontianak. This development research used the Borg & Gall model. The research instruments used were validation sheet, response questionnaire, and test of learning result. The results of the validity of the material and media experts showed the percentage of each valuation of 83.98% and 90.69%. Practical results in initial and main field trials showed the percentage of each valuation of 79.07% and 86.24%. Results of effectiveness in initial and main field trials showed the percentage of each valuation of 83.3% and 85%. Item discrimination power of the initial and main field tests was not found to be a negative category, so no items were discarded, while for the difficulty level of the items on the initial and main field trials was only easy and medium category. Thus evaluation tool based on developed wondershare quiz creator can be declared eligible for using and has a variation of discrimination test items and level of difficulty of test items in the evaluation.Keywords: Evaluation Tool, Colloid Material, Wondershare Quiz Creator
ABSTRAKPemahaman siswa terhadap materi dipengaruhi oleh media dan sumber belajar yang digunakan. Kurangnya kemampuan menganalisis dan penalaran terhadap materi yang diajarkan khususnya materi stoikiometri menimbulkan kurangnya minat belajar siswa, siswa tidak memiliki buku pegangan namun saat pembelajaran berlangsung siswa menggunakan buku paket yang jumlahnya tidak mencukupi selain itu hanya mencakup satu atau dua representasi saja. Penelitian ini bertujuan untuk mengembangkan modul pembelajaran kimia berbasis multipel representasi. Penelitian ini merupakan penelitian R&D yang mengadopsi pengembangan dari Borg & Gall. Pengambilan sampel menggunakan purposive sampling. Subjek dalam penelitian ini adalah peserta didik kelas X IPA 2 berjumlah 9 siswa pada uji coba lapangan awal dan 30 siswa kelas X IPA 1 pada uji coba lapangan utamaPengumpulan data menggunkan angket dan tes. Analisis data menggunakan analisis data skala likert. Hasil penelitian ini yaitu nilai kevalidan modul sebesar 91,5% ahli materi, dan ahli media sebesar 92,5%; kepraktisan modul dilihat dari angket respon siswa sebesar 88,17 dan 86,89; serta nilai keefektifan modul dilihat dari nilai ketuntasan belajar siswa sebesar 80,4%. Berdasarkan hasil penelitian yang diperoleh disimpulkan bahwa modul yang dikembangkan telah layak, praktis dan efektif digunakan guru dan siswa dalam proses pembelajaran. ABSTRACTStudents' understanding towards learning materials is generally influenced by the learning sources used. Lack of analytical skills and reasoning of the material taught especially stoichiometric material leads to a lack of interest in students' learning, students do not have a handbook but while learning takes place students use an inadequate number of textbooks in addition to covering only one or two representations. This study aimed to develop a learning module of multiple representation-based Stoichimetry concept. This study was a R &D method which adopting development of Brog & Gall. Sampling used purposive sampling. Subject in this research were students of class X IPA 2 as many as 9 students at initial field trials and 30 students of X IPA 1 at main field trials. Data collecting technique used were questionnaire and test. The data was analyzed by using Likert scale. The study revealed that the material validity by the material expert was 91,5%, and the validity by the media expert was 92,5%. The responses from the questionnaire on the practicality of the module were 88,17% and 86,89%. The effectiveness of the module could be seen from the students' learning mastery value by 80,4%. In conclusion, the module that has been developed is considered feasible, practical, and effective to be used for both teachers and students in teaching learning process.
In general, the used evaluation form to measure the students’ abilities is evaluation form in multiple choice and essay, but this evaluation still has weaknesses which are there are possibilities that the students do not know the correct answer and it has low realibility. From the weaknesses, the researcher wanted to produce two levels multiple choice diagnostic test assessment instrument in order to find outthe passing of the students’ outcomes with 21 students for the first trial and 118 students for the main trial. This research consisted of 7 steps which were (1) Research and the collection of information, (2) Planning, (3) The development of introductory product, (4) Preliminary trial, (5) The revision on main product, (6) Field trial, and (7) The revision of product. The research result showed that the two levels multiple choice diagnostic test was feasible to be used. The test result from 118 students using the two levels multiple choice diagnostic test showed the validity value of Vainstrument was 3.97, the effectiveness value was 85.57 %, and the practical value was 78.80%. The obtained test result, before and after using the two levels multiple choice diagnostic test showed that there was improvement on students’ learning outcomes which was 59.3 %. Therefore, the two levels multiple choice diagnostic test can measure and improve the students’ learning outcomes.Keywords: Development, Two Levels Multiple Choice, Two Levels Multiple Choice DiagnosticTest
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