Judul: Antibiotic Resistance in Escherichia coli Isolates from  Chicken Noodle Meat around Dramaga Campus IPB University.
Abstrak: Mi ayam merupakan salah satu pangan asal hewan yang berpotensi terkontaminasi bakteri Escherichia coli (E. coli) resistan terhadap antibiotik. Bakteri ini mengancam kesehatan masyarakat karena sulit mengendalikan penyebaran bakteri penyebab infeksi. Tujuan penelitian ini menentukan tingkat resistansi antibiotik isolat E. coli dari daging ayam cincang mi ayam yang dijual di lingkar Kampus Dramaga, IPB University. Pengujian resistansi menggunakan metode Kirby-Bauer disk diffusion dan mengacu pada Clinical Laboratory Standard Institute 2023. Sebanyak 43 isolat teridentifikasi E. coli, tingkat resistansi E. coli diperoleh terhadap ampisilin (49%), tetrasiklin (44,2%), sulfametoksazol trimetoprim (33%), kloramfenikol (23,3%), streptomisin (16,3%), dan sefotaksim (9,3%). Selain itu, isolat E. coli menunjukkan resistansi tingkat intermediet pada antibiotik streptomisin (35%) dan sefotaksim (35%). Isolat bakteri E. coli masih sensitif terhadap kloramfenikol (72%), sulfametoksazol-trimetoprim (65,1%), tetrasiklin (56%), sefotaksim (56%), streptomisin (49%), dan ampisilin (35%). Terdapat isolat E. coli bersifat multidrug-resistance dengan pola ampisilin streptomisin-tetrasiklin-sefotaksim-sulfametoksazol trimetoprim-kloramfenikol. Tingkat resistansi antibiotik yang tinggi pada isolat E. coli memicu masalah kesehatan masyarakat karena bakteri yang resistan dapat menyebar ke tubuh melalui konsumsi makanan yang terkontaminasi, menimbulkan risiko infeksi yang lebih besar., Chicken noodles are one of the animal-derived foods that have the potential to be contaminated with antibiotic-resistant Escherichia coli (E. coli) bacteria. These bacteria threaten public health because it is difficult to control the spread of bacteria that cause infections. The purpose of this study was to determine the level of antibiotic resistance of E. coli isolates from minced chicken meat chicken noodles sold around the Dramaga Campus, IPB University. Resistance testing uses the Kirby-Bauer disk diffusion method and refers to the Clinical Laboratory Standard Institute 2023. A total of 43 E. coli isolates were identified, the resistance level of E. coli was obtained against ampicillin (49%), tetracycline (44,2%), sulfamethoxazole-trimethoprim (33%), chloramphenicol (23,3%). streptomycin (16,3%), and cefotaxime (9,3%). In addition, E. coli isolates showed intermediate level resistance to streptomycin (35%) and cefotaxime (35%) antibiotics. E. coli isolates were still sensitive to chloramphenicol (72%), sulfamethoxazole- trimethoprim (65,1%), tetracycline (56%), cefotaxime (56%), streptomycin (49%), and ampicillin (35%). There were multidrug-resistant E. coli isolates with ampicillin-streptomycin-tetracycline-cephotaxime-sulfamethoxazole trimethoprim chloramphenicol pattern. The high level of antibiotic resistance in E. coli isolates triggers public health concerns as resistant bacteria can spread to the body through the consumption of contaminated food, posing a greater risk of infection.
Keyword: antibiotik, daging ayam, resistansi, escher

Judul: Resistance of Escherichia coli Isolates in  Shredded Chicken Meat of Chicken Porridge Sold Around the Campus of IPB  University
Abstrak: Bubur ayam merupakan salah satu pangan asal hewan yang berpotensi terkontaminasi bakteri Escherichia coli (E. coli) resistan terhadap antibiotik. Escherichia coli yang resistan terhadap antibiotik menjadi masalah kesehatan di dunia karena menyebabkan pengobatan menjadi tidak efektif. Tujuan penelitian ini yaitu mendapatkan gambaran tingkat resistansi antibiotik dari bakteri E. coli yang diisolasi dari daging ayam suwir bubur ayam yang dijual di lingkar Kampus IPB, Dramaga, Bogor. Sebanyak tujuh isolat yang teridentifikasi E. coli dijadikan sampel dalam penelitian ini. Pengujian resistansi menggunakan metode Kirby-Bauer disk diffusion dan mengacu pada Clinical Laboratory Standard Institute 2023. Resistansi E. coli dari daging ayam suwir bubur ayam menunjukkan terhadap tetrasiklin dengan persentase (57%; 4/7) dan diikuti ampisilin dan sulfametoksazol trimetoprim sebesar (14%; 1/7). Isolat E. coli juga menunjukkan hasil intermediet pada ampisilin sebesar (57%; 4/7). Semua isolat bakteri E. coli masih sensitif terhadap streptomisin (100%), sefotaksim (100%), dan kloramfenikol (100%), sedangkan isolat masih sensitif terhadap sulfametaksazol-trimetoprim (86%), tetrasiklin (43%), dan ampisilin (29%). Isolat E. coli bersifat multi-drug resistance dengan pola ampisilin-tetrasiklin-sulfametoksazol trimetoprim.
Keyword: antibiotik, daging ayam, Escherichia coli, resistansi

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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