Kinetics of invertase synthesis by Saccharomyces cerevisiae in synthetic medium

Present investigation deals with optimization of appropriate substrate concentration and incubation temperature both for growth of Saccharomyces cerevisiae and invertase production. Submerged fermentation technique was employed in the present study. The maximal production of invertase during the course of study was achieved after 48 h of incubation using initial sucrose concentration, 15.0 g l-1. The sugar consumption and dry cell mass were also examined. Data was subjected to kinetic analysis and on the basis of kinetic parameters such as Yp/x (amount of enzyme produced mg-1 cell mass), Yp/s (amount of enzyme produced mg-1 sugar consumed), Yx/s (mg cells mg-1 substrate consumed), Ys/x (mg sugar consumed mg-1 cell mass produced), qp (Amount of enzyme produced mg-1 sugar consumed h-1), qs (mg mg-1 cells h-1), qx (mg cells mg-1 sugar consumed h-1), µ (mg cells produced h-1), it was found that temperature had a direct influence both on substrate consumption and synthesis of enzyme. Similarly, higher concentrations of sucrose in fermentation medium induced catabolite repression of yeast invertase

IN VITRO SUSCEPTIBILITY OF ISOLATED SHIGELLA FLEXNERI AND SHIGELLA DYSENTERIAE TO THE ETHANOLIC EXTRACTS OF TRACHYSPERMUM AMMI AND PEGANUM HARMALA

Objective: This study represents the first attempt to investigate the antimicrobial activity of Peganum harmala, and Trachyspermum ammi seeds extract against the isolated bacillary dysentery-causing microorganisms. Methods: T. ammi and P. harmala were extracted by 96% ethanol using Soxhlet apparatus. The extracts were screened for their phytochemical constituents. Their antimicrobial activity against the isolated dysentery-causing microorganisms was evaluated using the agar diffusion method. Results: The antimicrobial activity result showed that, the two isolated bacteria, Shigella flexneri, and Shigella dysenteriae were found to be sensitive to the extract of T. ammi seed with inhibition zones up to 25 mm, compared to the inhibition zone of 20 mm produced by Gentamycin standard drug, this is mainly due to the presence of the different phytochemical in the extract such as tannin, flavonoids, terpenoids which are well known for their antimicrobial effects. The two isolated bacteria were found to be insensitive (zero mm) to P. harmala extract, Amoxicillin, and Amoclan (Amoxicillin+clavulanic acid) standard drugs, this is due to the fact that, the phytochemicals constituents of P. harmala possess the antagonistic effect to each other’s. Addition to; these bacteria became resistant to both Amoxicillin and Amoclan. Conclusion: From the results it concludes, T. ammi seeds extract had a considerable level of antimicrobial activity against bacillary dysentery-causing microorganisms resistant to Amoxicillin and Amoxicillin+clavulanic acid drugs

PENINGKATAN KEMAMPUAN PEMECAHAN MASALAH MATEMATIS SISWA DENGAN MENGGUNAKANMODEL PROBLEM BASED LEARNING DI KELAS X MAN 1 KOTA TERNATE

Penelitian ini dilakukan dengan tujuan untuk mengetahui peningkatan kemampuan pemecahan masalah matematis siswa setelah diterapkannya model Problem Based Learning. Penelitian ini merupakan penelitian eksperimen. Desain penelitian eksperimen ini menggunakan bentuk Pre Experimental  tipe One Group Pretest-Posttest Design. Dalam penelitian ini di ambil satu kelas sebagai sampel penelitian untuk diberi perlakuan pembelajaran. Kelas eksperimen diberikan pembelajaran dengan menggunakan model Problem Based Learning. Instrument yang digunakan pada penelitian ini adalah intrumen tes dalam bentuk essay. Untuk mengetahui peningkatan kemampuan pemecahan masalah matematis  setelah diterapkannya model Problem Based Learning data dianalisis dengan menggunakan N-Gain dan One-Sample t Test.Hasil analisis data menunjukkan bahwa terdapat peningkatan kemampuan pemecahan masalah matematis siswa setelah diterapkannya model Problem Based Learning.   Kata Kunci: Kemampuan Pemecahan Masalah Matematis dan Problem Based Learnin

Developing Mathematics Written Communication through Case-Based Learning

Mathematical education, as it is now practiced, has many problems. Students that were taught using traditional instruction were only taught to listen. Without the input and feedback of the pupils, the teacher controls the learning process. Students were unable to improve their communication abilities and lacked learning independence. This study aimed to ascertain how case-based learning affected students' mathematics communication skills. The study had a posttest-only design and was a quasi-experimental investigation. The control class received standard instruction, whereas the experiment class received case-based learning instruction. The ability of students to communicate mathematically was the dependent variable in this study. The independent variables in this study were case-based learning and independent variables. Forty-six pre-service mathematics teachers from two full classes served as the research participants in their fifth semester. The tests of prior knowledge and mathematical communication skills were used as study tools. According to the research findings, there is a difference in students' capacity for mathematical communication between those who receive case-based learning instruction and those who receive traditional instruction. The experiment class had better student communication skills than the control group (p-value = 0.047). As a result, case-based learning is one option for enhancing students' communication abilities.

PENGGUNAAN HYPERMEDIA PADA MATA KULIAH KALKULUS II UNTUK MENINGKATKAN HASIL BELAJAR DAN KEMAMPUAN BERPIKIR KRITIS MAHASISWA PROGRAM STUDI PENDIDIKAN MATEMATIKA FKIP UNKHAIR

Penelitian ini bertujuan untuk merancang dan menggunakan hypermedia sebagai upaya peningkatan hasil belajar dan keterampilan berpikir kritis mahasiswa pada mata kuliah Kalkulus II. Penelitian ini merupakan penelitian eksperimen yang dilakukan pada mahasiswa program studi pendidikan matematika FKIP UNKHAIR yang mengontrak mata kuliah Kalkulus II tahun akademik 2011-2012. Pengumpulan data dilakukan dengan teknik tes melalui instrumen tes berupa soal-soal essay. Berdasarkan hasil analisis data disimpulkan bahwa penggunaan multimedia hypermedia lebih efektif dalam meningkatkan hasil belajar dan keterampilan berpikir kritis mahasiswa dibandingkan dengan pembelajaran konvensional

Verbs and gender: the hidden agenda of a multicultural society

This study explores the issue of gender inequality displayed in action verbs found in English language secondary school textbooks using the Hidden Curriculum Theory. The two aspects of hidden curriculum are the frequency imbalance, i.e., male occurrences are more than female, and gender stereotyping based on roles, i.e., masculine against feminine activities. This study used both quantitative and qualitative methods for collecting data. Wordsmith Tools 4.0 (WST) was used to analyse five categories of action verbs: activity verbs, process verbs, verbs of bodily sensation, transitional event verbs, and momentary verbs. The concordance tool from the WST was used to tabulate occurrences based on gender portrayals. School teachers who taught English at secondary schools were also interviewed to validate the findings and link them to the theoretical framework used. The findings reveal gender inequality is evident in these textbooks

KEMAMPUAN PEMAHAMAN KONSEP DAN PENALARAN MAHASISWA PROGRAM STUDI PENDIDIKAN FISIKA DALAM MATA KULIAH KALKULUS DENGAN PENERAPAN CTL BERBASIS PENDEKATAN PEMECAHAN MASALAH

ABSTRAK. Penelitin ini bertujuan untuk: (1) meningkatkan kemampuan pemahaman konsep mahasiswa Program Studi Pendidikan Fisika dalam mata kuliah kalkulus dengan menerapkan pembelajaran CTL berbasis pendekatan pemecahan masalah; (2) meningkatkan kemampuan penalaran mahasiswa Program Studi Pendidikan Fisika dalam mata kuliah kalkulus dengan menerapkan strategi pembelajaran CTL berbasis pendekatan pemecahan masalah. Penelitian ini merupakan penelitian eksperimen dengan teknik yang digunakan dalam memperoleh data yaitu dengan observasi, tes uraian, dan dokumentasi. Selanjutnya, pengujian hipotesis  dalam penelitian ini menggunakan uji inferensial dengan bantuan program SPSS 24. Hasil penelitian  menunjukkan bahwa: (1) terdapat peningkatan kemampuan pemahaman konsep matematis mahasiswa Program Studi Pendidikan Fisika dalam mata kuliah kalkulus dengan menerapkan strategi pembelajaran kontekstual berbasis pendekatan pemecahan masalah; (2) terdapat peningkatan kemampuan penalaran matematis mahasiswa Program Studi Pendidikan Fisika dalam mata kuliah kalkulus dengan menerapkan strategi pembelajaran kontekstual berbasis pendekatan pemecahan masalah. Kata Kunci: CTL;Pendekatan Pemecahan Masalah; Pemahaman Konsep; penalaran; Kalkulus ABSTRACT. This research aims to: (1) improve the students' understanding of the concept of Physics Education Study Program in calculus course by applying CTL learning based on problem solving approach; (2) to improve the students' reasoning ability in the study program of physics in calculus course by applying CTL learning strategy based on problem solving approach. This research is an experimental research with techniques used in obtaining data that is by observation, description test, and documentation. Furthermore, hypothesis testing in this study using inferential test with the help of SPSS 24 program. The result of the research shows that: (1) there is an increase of understanding ability of mathematical concept of Physics Education Study Program in calculus course by applying contextual learning strategy based on problem solving approach; (2) there is improvement of mathematical reasoning ability of student of Physics Education Study Program in calculus course by applying contextual learning strategy based on problem solving approach. Keywords: CTL; Problem Solving Approach; Understanding Concepts; reasoning; Calculu

Peningkatan Kemampuan Representasi Matematis Siswa SMP pada Materi Diagram Venn melalui Pendekatan Realistic Matematis Education

Penelitian eksperimen ini bertujuan untuk  mengetahui 1) kemampuan representasi matematis siswa kelas VII pada materi Diagram Venn melalui pendekatan matematika Realistik, 2) pendekatan matematika Realistik dapat  meningkatkan kemampuan reprsentasi matematis siswa dalam menyelesaikan Diagram Venn. Penelitian ini menggunakan desain penelitian One Group Pretest–Posttes Design dan menjadikan siswa kelas VII yang berjumlah 38 siswa sebagai sampel penelitian. Data penelitian dikumpulkan melalui teknik tes untuk mengetahui peningkatan kemampuan representasi matematis siswa terhadap penerapan model Realistic Mathematics Education (RME). Teknik analisis data menggunakan rumus PAP, N.Gain (g), uji Normalitas, dan uji Hipotesis. Hasil tes penelitian dianalisis untuk memperoleh tingkat kemampuan siswa dalam menyelesaikan soal dengan kualifikasi sebagai berikut: kualifikasi memuaskan sebesar 78,94% dan kualifikasi baik sebesar 21,05%. Pada taraf nyata α = 0,05 diperoleh thitung = 2,88 > ttabel = 1,684. Oleh karena itu hipotesis H0 ditolak, yang berarti bahwa terdapat peningkatan kemampuan representasi matematis siswa tergolong tinggi dengan nilai N Gain yang diperoleh yakni 0,88. Dengan demikian terdapat peningkatan kemampuan representasi matematis siswa melalui model pendekatan RME pada siswa SMP Negeri 4 Mangoli Selatan.Kata Kunci : Realistik Matematis Education, Kemampuan Representasi, Diagram Ven