Judul: Effect of Saccharomyces cerevisiae (BY4741) on Intestinal Bacteria, Neurogenesis and Behavior in Mice (Mus musculus)
Abstrak: Microbiota-gut-brain axis memengaruhi proses neurogenesis di otak. Neurogenesis dapat ditingkatkan dengan pemberian probiotik. Saccharomyces cerevisiae memiliki peran sebagai probiotik. Penelitian ini bertujuan mengetahui pengaruh pemberian S. cerevisiae terhadap mikrobiota usus, neurogenesis pada hipokampus, serta perilaku. Penelitian ini terdiri atas kelompok kontrol, kelompok perlakuan 100µl (~103 cfu), 100µl (~106 cfu), dan 100µl (~109 cfu) S. cerevisiae (BY4741). Analisis mikroorganisme saluran pencernaan dilakukan dengan mengisolasi feses. Analisis perilaku yang dilakukan yaitu pembelajaran spasial dan perilaku kecemasan. Analisis neurogenesis dilakukan dengan membuat preparat histologi otak dengan menggunakan pewarna hematoksilin-eosin. Data diuji statistik melalui independent-samples t-test. Pemberian S. cerevisiae (BY4741) menjaga konsentrasi normal bakteri asam laktat dan E. coli. Neuron baru dan penyimpanan memori yang berada pada tingkat kematangan berbeda pada ~106 cfu/100µl tidak meningkatkan kinerja memori spasial. Perubahan konsentrasi bakteri saluran pencernaan mendukung peningkatan persentase neural progenitor cell (NPC) pada konsentrasi ~109 cfu/100µl sehingga sejalan dengan menurunnya perilaku kecemasan dan kinerja memori spasial yang meningkat. Peningkatan persentase densitas NPC yang secara tidak langsung berpengaruh pada penurunan perilaku kecemasan, serta peningkatan kinerja memori spasial., Microbiota-gut-brain axis influences the neurogenesis process. Neurogenesis can be increased by administering probiotics. Saccharomyces cerevisiae has a role as a probiotic. This study aimed to determine the effect of the provision of S. cerevisiae on the intestinal microbiota, behavior, and hippocampal neurogenesis. This study consisted of control group, the treatment group 100µl (~103 cfu), 100µl (~106 cfu), dan 100µl (~109 cfu) of S. cerevisiae (BY4741) with treatment for 4 weeks. Analysis of digestive tract microorganisms was carried out by from fecal samples. Anxiety behavior and memory performance analysis were carried out every week. Neurogenesis analysis was performed by making brain histological preparations using haematoxylin-eosin dye. The data were tested statistically through the independent-samples t-test. The provision of S. cerevisiae (BY4741) in this study maintained normal concentrations of lactat acid bacteria and E. coli. New neurons and memory stores that were at different maturity levels at ~ 106 cfu/100 µl did not improve spatial memory performance. The difference in the concentration of gastrointestinal bacteria supported the increase in the percentage of neural progenitor cell (NPC) at a concentration of ~ 109 cfu/100µl so that it was in line with decreased anxiety behavior and increased spatial memory performance. Increasing the percentage of NPC density indirectly affects the decrease in anxiety behavior, as well as an increase in spatial memory performance.
Keyword: Kecemasan, memori spasial, microbiota-gut-brain axis, NPC

Judul: The Effect of Probiotic Saccharomyces boulardii on Mice's Memory Spatial, Behavior, and Aerobic Gut Bacteria
Abstrak: Saccharomyces boulardii can regulate intestinal microbiota homeostasis and secrete polyamines which play roles in proliferation, differentiation, cell growth, memory performance, and metabolism. This study aims to determine the effect of S.boulardii on mice’s aerobic gut bacteria, spatial memory, and behavior. 12 mice were used and divided into 4 groups, the control group and the treatment group S.boulardii 32.52 mg/kg BW (P1), 65mg/kg BW (P2), and 130 mg/kg BW (P3). The research methods used included material preparation, treatment, analysis quantitative of aerobic gut bacteria, behavioral analysis, spatial memory performance analysis, neurogenesis analysis in the hippocampus, and data analysis using ImageJ and ANOVA. Mice treated with S.boulardii for 31 days showed an increase in the abundance of aerobic and lactic acid bacteria and a decrease in E.coli in the digestive tract. In addition, the administration of S.boulardii had an effect on the learning and memory of mice. This was indicated by the increase in the number of NPC and granular cells and the decrease in apoptotic cells in the hippocampus. However, the administration of S.boulardii did not have an effect on reducing stress and anxiety. This can happen because stress and anxiety are influenced by environmental and social factors., Saccharomyces boulardii memiliki kemampuan untuk mengatur homeostasis mikrobiota usus, mensintesis dan mensekresi poliamina yang berperan dalam proliferasi sel, diferensiasi sel, pertumbuhan sel, kinerja memori, dan metabolisme. Penelitian ini bertujuan untuk mengetahui pengaruh S.boulardii terhadap bakteri aerobik usus, memori spasial, dan perilaku mencit. Penelitian dilakukan pada 12 ekor mencit yang dibagi menjadi 4 kelompok yaitu kelompok kontrol dan kelompok perlakuan S.boulardii 32,52 mg/kg BB (P1), 65mg/kg BB (P2), dan 130 mg/kg BB (P3). Metode penelitian yang digunakan meliputi persiapan bahan, perlakuan, pengujian kuantitatif bakteri aerobik usus, analisis perilaku, analisis kinerja memori spasial, analisis neurogenesis di hipokampus, dan analisis data menggunakan ImageJ dan ANOVA. Mencit yang diberi perlakuan S.boulardii selama 31 hari menunjukkan peningkatan kelimpahan bakteri aerob dan asam laktat serta penurunan bakteri E.coli di saluran pencernaan. Selain itu, pemberian S.boulardii berpengaruh pada pembelajaran dan memori mencit. Hal ini ditunjukkan dengan peningkatan jumlah NPC dan sel granular serta penurunan sel apoptosis di hipokampus. Namun, pemberian S.boulardii tidak berpengaruh terhadap penurunan stres dan kecemasan. Hal ini dapat terjadi karena stres dan kecemasan dipengaruhi oleh faktor lingkungan dan social.
Keyword: Anxiety, Gut microbiota brain axis, Gut microbiota, Neurogenesis, Probiotic

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
Keyword: