Judul: Uji Toksisitas Akut Sari Buah Jeruk (Citrus sinensis) pada Tikus (Rattus norvegicus) Pediatri
Abstrak: Sementara ini, belum ada standar pengujian keamanan sediaan untuk pediatri manusia menggunakan hewan pediatri. Penelitian ini mengadopsi standar uji toksisitas akut (dengan tikus dewasa) di tikus pediatri menggunakan sari buah jeruk. Sari buah jeruk merupakan produk turunan jeruk yang umum dikonsumsi oleh anak-anak karena rasanya yang enak serta kandungannya yang bermanfaat bagi kesehatan. Pengamatan dilakukan pada bobot badan, fisiologi, serta makropatologi organ 20 ekor tikus berumur 3 minggu. Penelitian ini diharapkan mampu menggambarkan keamanan sari jeruk pada pediatri dan menjadi standar pengujian toksisitas akut untuk pediatri. Sari jeruk diperas secara manual dari buah jeruk manis. Tikus dibagi menjadi 5 kelompok perlakuan yaitu kelompok kontrol dan 4 perlakuan dosis sari buah jeruk (5, 10, 15, 20 g/kg BB). Tikus diberi perlakuan melalui rute oral pada hari pertama, diamati selama 14 hari, dan dinekropsi pada hari ke-14. Pemberian sari jeruk hingga dosis 20 g/kg BB tidak menyebabkan kematian tikus pediatri. Selain itu, tidak ditemukan perbedaan signifikan pada bobot badan, frekuensi nafas, denyut jantung, suhu rektal, dan tampilan makroanatomi lima organ penting tikus pediatri. Hasil yang didapatkan pada penelitian ini serupa dengan temuan National Health and Nutrition Examination Survey (O’Neil et al. 2003) yang menyatakan bahwa konsumsi 750 mL sari jeruk (±21 g/kg BB) menunjukkan efek positif pada remaja. Metode pada penelitian ini dapat membuktikan bahwa sari buah jeruk bersifat aman untuk pediatri sehingga dapat digunakan sebagai acuan untuk uji toksisitas akut dengan hewan pediatri., Currently, there is no available standard for testing the safety of preparations for human pediatrics using pediatric animals. This study adopts a standard acute toxicity test (using adult rats) on pediatric rats using orange juice. Orange juice is an orange derivative product that is commonly consumed by children because it tastes good and contains health benefits. Body weight, physiology, and organ macropathology of 20 rats (3 weeks old) were observed. It is hoped that this research will be able to describe the safety of orange juice in pediatrics and become a standard for acute toxicity testing using pediatric animals. The orange juice is squeezed manually from sweet oranges. Rats were divided into 5 treatment groups, namely the control group and 4 treatments with doses of orange juice (5, 10, 15, 20 g/kg BW). Rats were treated via the oral route on the first day, observed for 14 days, and necropsied in the 14th day. Administration of orange juice up to a dose of 20 g/kg BW did not cause any death on pediatric rats. There were also no significant differences found in body weight, respiratory frequency, heart rate, rectal temperature, and macro-anatomical appearance of five important organs in pediatric rats. The results obtained in this study are similar to the findings of the National Health and Nutrition Examination Survey (O’Neil et al. 2003) which stated that consumption of 750 mL of orange juice (±21 g/kg BW) showed positive effects in young adults. The method in this research can prove that orange juice is safe for pediatrics so that it can be used as a reference for acute toxicity tests using pediatric animals.
Keyword: pediatri, sari buah jeruk, uji toksisitas akut

Judul: Comparison of Gastric Emptying Time and Intestinal  Motility Responses of Pediatric and Adult Rats (Rattus norvegicus) with  Orange Juice
Abstrak: Multiproses pencernaan menjadi faktor yang perlu dipertimbangkan untuk mencapai keberhasilan dari suatu pengobatan. Faktor umur diduga memengaruhi kinerja dan penyerapan suatu sediaan dari formulasi oral. Penelitian ini bertujuan mengetahui perbandingan gastric emptying time (GET) dan respons motilitas usus tikus pediatri dan dewasa yang diberikan sari jeruk sebagai model obat asam. Tikus diberikan sediaan sari jeruk sesuai dosis kelompok perlakuan melalui rute oral. Selanjutnya, tikus dilakukan anestesi dan pembedahan ruang abdomen. Organ lambung diperhatikan dan dicatat waktu hingga isi organ tersebut kosong. Setelah didapatkan GET, motilitas usus tikus diamati dengan metode gastrointestinal transit. Hasil tersebut dianalisis menggunakan two-way ANOVA. Rata-rata GET fisiologis normal tikus pediatri dan dewasa adalah 59,00 dan 54,67 menit. Sementara itu, pemberian sari jeruk dengan dosis tertinggi (20 g/kg BB) memperpanjang GET secara signifikan. Faktor keasaman, konsistemsi, dan kandungan karbohidrat sari jeruk memengaruhi perbedaan GET. Terhadap motilitas usus, peningkatan dosis pemberian sari jeruk dan umur tikus meningkatkan rasio marker dan kecepatan peristaltik secara signifkan. Kondisi ini menunjukkan bahwa peningkatan dosis sari jeruk memperpanjang GET tikus, serta peningkatan baik umur dan dosis pemberian sari jeruk meningkatkan motilitas usus., Multiprocess digestion is a factor that needs to be considered to achieve successful treatment. Age and dose factors are thought to influence the performance and absorption of oral formations. This study aims to determine the comparison of gastric emptying time (GET) and intestinal motility responses of pediatric and adult rats given orange juice as a model of acid medication. Rats were given orange juice according to the dose of the treatment group via the oral route. The rats underwent anesthesia and the abdominal cavity was dissected. The gastric organs were observed and the GET was recorded. After obtaining of GET, intestinal motility was observed using the gastrointestinal transit method. The results were analyzed using two-way ANOVA. Physiologically, the average of GET for pediatric and adult rats is 59,00 and 54,67 minutes. Meanwhile, administration of orange juice at the highest dose (20 g/kg BW) significantly prolonged of GET. The acidity, consistency and carbohydrate of orange juice affect of GET. Increasing the dose and age of the rats also significantly increased the marker ratio and peristaltic speed. This condition shows that increasing the dose of orange juice prolongs the GET of rats, and increasing both age and dose increases intestinal motility.
Keyword: pediatri, tikus, gastric emptying time, sari jeruk, motilitas usus

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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