Development of Animation Media to Improve Students\u27 Learning Motivation and Chemistry Learning Achievement at Sman 4 Praya

This study aims to develop chemistry animation media of redox reactions. The study was conducted by using the approach of R & D by Borg & Gall including preliminary study, early product development, validation, limited testing, product revision, and the testing stage. To examine the effectiveness of media on students\u27 motivation and learning outcomes using the stages of classroom action research (CAR) was conducted at SMAN 4 Praya. Data of the study was collected through activity observation, questionnaires, and achievement test. Based on the result, it can be concluded that students\u27 cognitive achievement hasclassical completeness by 61% in cycle 1 and 78 % in cycle 2. The average of students\u27 motivation also improveby 69 in cycle 1 and by 75 in cycle 2 although both are included in the middle category

Desain Sistem Kendali Rotary Pendulum Dengan Sliding-PID

Kebanyakan sistem kontrol yang ada di dunia nyata adalah sistem nonlinier sehingga sulit untuk dikenda-likan. Rotary pendulum adalah sistem yang mensimulasikan sebuah mekanisme kontrol untuk mengatur permasalahan kestabilan. Permasalahan utama dalam desain sistem kendali untuk rotary pendulum adalah menstabilkan batang pendul-um di daerah ekuilibrium pada arm yang digerakkan oleh motor. Pada penelitian ini dilakukan perancangan sistem kendali dengan menggunakan kendali PID dan Sliding-PID. Sliding-PID merupakan gabungan antara Sliding Mode Con-troller dan PID controller. Pemodelan sistem dilakukan dengan Simulink Matlab yang berdasarkan persamaan kine-matika dan dinamika dari sistem. Berdasarkan penelitian ini, dapat disimpulkan bahwa penggunaan kendali Sliding-PID menghasilkan respon yang lebih baik dibandingkan dengan kendali PID. Hal tersebut dapat ditunjukkan dengan nilai maksimum overshoot pada kendali Sliding-PID (0% untuk sudut dan sudut ) lebih kecil daripada kendali PID (9.4664% untuk sudut dan 7.7107% untuk sudut ). Sedangkan waktu yang diperlukan untuk seluruh sistem rotary pendulum (untuk menstabilkan sudut dan sudut ) dengan kendali Sliding-PID (5.8591 detik) lebih besar jika dibandingkan dengan kendali PID (0.5190 detik). Selain itu steady state error dari kendali Sliding-PID (4.94%) lebih besar daripada kendali PID (4.81%)

DEVELOPMENT OF ANIMATION MEDIA TO IMPROVE STUDENTS’ LEARNING MOTIVATION AND CHEMISTRY LEARNING ACHIEVEMENT AT SMAN 4 PRAYA

This study aims to develop chemistry animation media of redox reactions. The study was conducted by using the approach of R & D by Borg & Gall including preliminary study, early product development, validation, limited testing, product revision, and the testing stage. To examine the effectiveness of media on students’ motivation and learning outcomes using the stages of classroom action research (CAR) was conducted at SMAN 4 Praya. Data of the study was collected through activity observation, questionnaires, and achievement test. Based on the result, it can be concluded that students’ cognitive achievement hasclassical completeness by 61% in cycle 1 and 78 % in cycle 2. The average of students’ motivation also improveby 69 in cycle 1 and  by 75 in cycle 2 although both are included in the middle category

Cultivation conditions for phytase production from recombinant escherichia coli DH5α

Response surface methodology (RSM) was used to optimize the cultivation conditions for the production of phytase by recombinant Escherichia coli DH5α. The optimum predicted cultivation conditions for phytase production were at 3 hours seed age, a 2.5% inoculum level, an L-arabinose concentration of 0.20%, a cell concentration of 0.3 (as measured at 600 nm) and 17 hours post-induction time with a predicted phytase activity of 4194.45 U/mL. The model was validated and the results showed no significant difference between the experimental and the predicted phytase activity (P = 0.305). Under optimum cultivation conditions, the phytase activity of the recombinant E. coli DH5α was 364 times higher compared to the phytase activity of the wild-type producer, Enterobacter sakazakii ASUIA279. Hence, optimization of the cultivation conditions using RSM positively increased phytase production from recombinant E. coli DH5α

Evaluation of Bacteriostatic Effect of Methanolic Extract of Guiera senegalensis on Some Clinical Bacteria

Abstract -Guiera senegalensis (family: Combretaceae) leaves have been in use for quite long period of time, as traditional medicine in rural area