One type of pesticide that is widely used is a group of organophosphates with chlorpyrifos as the active ingredients, because it has more favorable characteristics such as easy to decompose and short persistence time. However, the use of pesticides in addition to leaving residues that can cause environmental pollution, also cause disruption to human health and inhibit trade. Therefore, it is necessary to monitor the use of pesticides through the fulfillment of the maximum residual limit (MRL) so as to ensure food safety by limiting pesticide residue levels on agricultural products. The purpose of this study was to determine the residual levels of chlorpyrifos in cabbage vegetables with previously optimized and validated HPLC methods. The sample of this research is vegetable cabbage taken from several traditional markets in North Sulawesi. Based on the results of the study, it was found that chlorpyrifos were detected in all samples analyzed, although the levels were still below the specified MRL value.  The results of this study can be a consideration for consumers and relevant agencies in North Sulawesi to more frequently monitor and evaluate the existence and use of these compounds.

Salah satu cara memberantas hama tanaman yang dilakukan oleh para petani di daerah Sulawesi Utara adalah menggunakan pestisida karena dianggap mudah didapat, harganya masih bisa dijangkau, dan sangat efektif membunuh hama tanaman. Namun, penggunaan pestisida yang tidak tepat mengakibatkan tertinggalnya residu pestisida tersebut pada tanaman sehingga menyebabkan pencemaran lingkungan, gangguan kesehatan pada manusia dan menghambat perdagangan. Oleh karena itu, perlu dilakukan pengawasan terhadap penggunaan pestisida melalui pemenuhan nilai batas maksimum residu (BMR). Penelitian ini bertujuan untuk menganalisis residu pestisida dalam tomat, cabai rawit, dan wortel dengan metode High Performance Liquid Chromatography (HPLC) yang telah dioptimasi dan divalidasi sebelumnya. Sampel penelitian berupa tomat, cabai rawit, dan wortel, diambil dari Pasar Tomohon, Pasar Karombasan, dan Pasar Kawangkoan, kemudian dibawa ke laboratorium Kimia Universitas Negeri Manado untuk diekstraksi dan dianalisis. Hasil penelitian ini menunjukkan bahwa pestisida dengan bahan aktif klorpirifos terdeteksi hampir pada semua sampel yang dianalisis, walaupun kadarnya masih berada di bawah nilai BMR yang ditetapkan, yaitu 1 mg/kg sampel. Kadar klorpirifos tertinggi dijumpai pada sampel tomat yang diambil dari Pasar Kawangkoan, yakni 0,3150 mg/kg sampel. Hasil penelitian ini juga menunjukkan bahwa sampel yang dicuci terlebih dahulu sebelum diekstraksi menyebabkan terjadinya penurunan kadar residu petisidanya.

This study uses the Research and Development (R&D) method. The purpose of this research is to develop and determine the quality of powerpoint-assisted learning media. The research subjects were students of class X MIA 3 at SMA Catholic Don Bosco Bitung. The validation test of the four learning media assessment teams obtained 78.5% results, the material assessment team's validation test obtained 79.8% results. The overall results from the validation of the media assessment team and the material assessment team obtained an average result of 79.2% in the valid assessment category. The results of the teacher's response obtained a total score of 44 with an average of 88% included in the very interested category. The results of the first trial of 5 students obtained an average percentage of 36% of students who answered Strongly Agree, 52% of students who answered Agree, 10% of students who answered Disagree, 2% of students who answered Disagree, and 0% Strongly Do not agree. The results of the second trial of 10 students after repairs were made, the average percentage obtained was 67% of students who answered Strongly Agree, 33% of students who answered Agree. Based on the results of the responses of the two groups, it can be concluded that there was an increase in the large group

This study aims to determine the effect of the implementation of the Teams Assisted Individualization (TAI) cooperative model with practicum on learning outcomes. This study used an experimental method, with a posttest only control design. The population was students of class X IPA and the sample of class X IPA 2, amounting to 26 people as the experimental class and class X IPA 1, totaling 26 people as the control class. The results of the research were analyzed by using the hypothesis (t-test) and the tcount was 1.778> t table 1.67. From these data, it can be influence the application of the cooperative model type TAI along with practicum on student learning outcomes in chemical bonding material.

Tujuan dari penelitian ini adalah untuk mengetahui besarnya Pengaruh Pembelajaran dalam jaringan (daring) terhadap hasil belajar siswa pada materi larutan elektrolit dan non elektrolit selama masa pandemi COVID-19. Penelitian ini dilakukan pada kelas X IPA SMA N 1 Tondano pada tahun ajaran 2020/2021. Sebanyak 25 siswa kelas X IPA 1 ditetapkan sebagai sampel penelitian. Penelitian ini menggunakan metode eksperimen dengan desain One-Shot Case Study. Hasil penelitian ini terdiri dari dua data, yaitu data angket untuk penilaian sikap siswa dan post test untuk penilaian hasil belajar siswa. Kedua data tersebut dianalisis dengan  menggunakan uji regresi korelasi, dan diperoleh persamaan regresinya yaitu Y = 9,5565 + 0,9073 x. Persamaan regresi tersebut menunjukkan bahwa semakin tinggi nilai sikap siswa (variabel X) maka semakin tinggi hasil belajar siswa (variabel Y). Dari pengujian korelasi Product moment yang dilakukan didapati koefisien korelasi (rxy) sebesar 0,6599, yang membuktikan bahwa antara variabel X dan variabel Y memiliki tingkat hubungan kuat. Untuk menghitung pengaruh sikap siswa pada pembelajaran daring terhadap hasil belajar, maka dihitung melalui rumus koefisien determinan, dan didapati besarnya pengaruh sikap siswa pada pembelajaran daring terhadap hasil belajar sebesar 43.55%. Sedangkan sisanya 56,45%  dipengaruhi oleh variabel lain berupa gangguan dan hambatan selama pembelajaran daring.