Judul: Studi Ekspresi Gen Nicastrin (NCSTN) sebagai Marka Penyakit  Alzheimer pada Otak Monyet Ekor Panjang (Macaca  fascicularis)
Abstrak: Penyakit Alzheimer merupakan penyakit neurodegeneratif yang dapat menyebabkan demensia, gangguan kognitif, hingga kematian pada penderita. Monyet ekor panjang (Macaca fascicularis) dipertimbangkan sebagai hewan model karena memiliki kemiripan dengan penyakit Alzheimer yang menyerang manusia. Gen NCSTN memiliki peran dalam pembentukan y-secretase yang dapat mempengerahui produksi peptida beta-amyloid (Aβ) sebagai marka patologis penyakit Alzheimer. Penelitian ini menganalisis ekspresi gen NCSTN sampel otak dari 6 ekor monyet ekor panjang yang terdiri dari regio korteks (n = 4) dan hipokampus (n = 6) dan dibagi menjadi kelompok usia dewasa (n = 5) dan kelompok usia tua (n= 5) menggunakan teknik RT-qPCR. Ditemukan perbedaan signifikan pada level ekspresi gen NCSTN antara kelompok usia dewasa dan kelompok usia tua (p = 0.008), namun tidak ditemukan perbedaan signifikan (p = 0.914) pada level ekspresi gen NCSTN antara regio korteks dan regio hipokampus. Level ekspresi gen NCSTN ditemukan paling tinggi pada regio korteks monyet ekor panjang kelompok usia dewasa. Level gen NCSTN berperan penting pada regio korteks monyet ekor panjang dan dapat berkaitan dengan resiko kejadian EOAD pada individu muda., Alzheimer's disease is a neurodegenerative disease that can cause dementia, cognitive impairment, and even death. The cynomolgus monkey (Macaca fascicularis) is considered as an animal model because it has similarities with Alzheimer's disease in humans. The NCSTN gene has a role in the formation of y- secretase which can influence the production of beta-amyloid (Aβ) peptides as a pathological marker of Alzheimer's disease. This study analyzed the expression of the NCSTN gene in brain samples from 6 cynomolgus monkeys consisting of the cortex (n = 4) and hippocampus (n = 6) regions and divided into the adult group (n = 5) and the aged group (n = 5) using the RT-qPCR technique. A significant difference was found in the expression level of the NCSTN gene between the adult and the aged group (p = 0.008), but no significant difference (p = 0.914) was found in the expression level of the NCSTN gene between the cortex and hippocampus regions. The expression level of the NCSTN gene was found to be highest in the cortex region. NCSTN gene plays important role in cortex region of cynomolgus monkeys and may be associated with the risk of EOAD in young individuals.
Keyword: Alzheimer’s disease, cortex, cynomolgus monkey, hippocampus, NCSTN

Judul: Identification of PCNA Gene Expression as the Marker of Alzheimer Disease in Cynomolgus Monkey (Macaca fascicularis)
Abstrak: Diagnosis dini dari penyakit Alzheimer hingga kini masih sulit untuk dilakukan, sehingga penting dilakukan penelitian lebih lanjut untuk menemukan biomarker yang dapat digunakan untuk mendeteksi penyakit ini secara dini. Proliferating Cell Nuclear Antigen (PCNA) dikenal sebagai marka proliferasi, yang berpotensi mendeteksi neurogenesis di otak. Penelitian ini bertujuan untuk mengidentifikasi ekspresi gen PCNA di otak sebagai marka penyakit Alzheimer pada Macaca fascicularis. Macaca fascicularis digunakan karena kemiripannya dengan manusia dalam kompleksitas perilaku, kemampuan kognitif yang tinggi dan pembentukan karakteristik patologis penyakit Alzheimer di otak. Penelitian ini menggunakan otak regio hipokampus dan korteks dari 7 ekor monyet. Monyet sebelumnya telah dibagi menjadi kelompok usia tua dan dewasa. Deteksi ekspresi gen PCNA dilakukan dengan metode RT-qPCR. Hasil penelitian menunjukkan ekspresi gen cenderung lebih tinggi pada monyet kelompok dewasa dan di regio hippocampus, meskipun berdasarkan analisis statistik tidak menunjukkan perbedaan yang signifikan., Early diagnosis of Alzheimer's is still difficult to do, thus it is important to carry out further research to find biomarkers that can be used to detect early Alzheimer's disease. Proliferating Cell Nuclear Antigen (PCNA) is known as a proliferation marker, which has the potential to detect neurogenesis in the brain. This study aimed to identify PCNA gene expression in the brain as a marker of Alzheimer’s disease in Macaca fascicularis. Macaca fascicularis was used in this study because of their similarities with humans in terms of their behavioral complexity, as well as high cognitive abilities and the formation of a pathological characteristic of Alzheimer's disease in the brain. This study used the brains of 7 monkeys in the hippocampus and cortical regions. Monkeys previously have been divided into old and adult age groups. The detection of PCNA gene expression was done using RT-qPCR method. The results showed the gene expression tended to be higher in the adult group and the hippocampus region, although based on statistical analysis showed no significant differences.
Keyword: Alzheimer's disease, Macaca fascicularis, Neurogenesis, PCNA, RT-qPCR

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.
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