Judul: Nori-like Product Formulation Based on Ulva lactuca and Gracilaria verrucosa with the Addition of Catfish Protein Hydrolyzate
Abstrak: Nori merupakan makanan tradisional Jepang yang terbuat dari rumput laut Porphyra. Diversifikasi Porphyra dengan rumput laut Ulva lactuca dan Gracilaria verrucosa dilakukan untuk mengurangi kebutuhan nori impor. Produk nori-like product diformulasikan dengan hidrolisat protein ikan lele untuk meningkatkan kandungan protein. Tujuan penelitian ini untuk menentukan pengaruh penambahan hidrolisat protein ikan terhadap karakteristik fisik, kimia, dan sensori nori-like product. Perlakuan konsentrasi hidrolisat protein ikan yang digunakan, yaitu 0% (FH0), 1% (FH1), 2% (FH2), dan 3% (FH3). Penambahan hidrolisat protein ikan lele memberikan pengaruh nyata terhadap karakteristik fisik, kimia, dan sensori nori-like product. Perlakuan terbaik yaitu formulasi FH3 dengan nilai sensori parameter kenampakan, warna, aroma, tekstur, kerenyahan, rasa, dan keseluruhan berturut-turut 3,80; 3,78; 3,48; 4,00; 3,93; 3,10; dan 3,53. Nilai proksimat kadar abu 12,42%, protein 13,10%, lemak 25,41%, dan serat kasar 7,72%. Formula FH3 memiliki nilai aw 0,55; kerenyahan 119,40 gf; serta intensitas warna L*, a*, b*, berturut-turut 28,70; 0,75; dan 2,86.
Keyword: Gracilaria verrucosa, hidrolisat protein ikan, nori-like product, Ulva lactuca

Judul: Formulation of Nori-Like from Green Seaweed Ulva lactuca with the Addition of  Boiled Water
Abstrak: Pembuatan produk nori-like dapat dilakukan menggunakan rumput laut Ulva lactuca, dengan menambahkan air rebusan pemindangan. Tujuan penelitian ini menentukan formula ¬nori-like terbaik, dari U. lactuca dengan penambahan air rebusan pemindangan, serta mengevaluasi karakteristik produk nori-like U. lactuca dengan penambahan air rebusan dari proses pemindangan. Pembuatan produk nori-like dilakukan dengan menambahkan konsentrat air rebusan pemindangan dengan jumlah yang berbeda dalam proses pengolahan. Formulasi terpilih, secara sensori, dalam pembuatan nori-like yaitu dengan menambahkan konsentrat air rebusan pemindangan sebanyak 3%. Produk nori-like yang dibuat pada penelitian ini memiliki nilai gizi yang lebih rendah dibandingkan nori yang telah komersil, akan tetapi hasil yang diperoleh telah menunjukkan bahwa penambahan 3% konsentrat air rebusan pemindangan dalam pembuatan nori-like dapat meningkatkan nilai gizi pada produk nori-like, dengan kadar air 12,77%, abu 14,53%, protein 17,02%, lemak 5,88%, dan serat pangan 25,77%. Asam amino yang mendominasi pada nori-like terpilih yaitu histidina, asam glutamat, dan glisina. Produk ini memiliki nilai aw 0,59 serta intensitas warna L,a,b berturut-turut 14,28, 0,76, dan 14,44., Nori-like products can be made using Ulva lactuca seaweed, with an additional boiled fish water. The purpose of this study was to determine the selected nori-like formula, made from U. lactuca with the addition of boiled fish water, and to evaluate the characteristics of nori-like from U. lactuca with the addition of boiled water from boiling process. The making of nori-like products was done by adding different amounts of boiled water concentrate during the process. The selected nori-like formula was made by adding 3% of the concentrated boiled water. The nori-like products made in this study contained a lower nutritional value than commercial nori, but the results obtained have shown that an additional 3% of the boiled water concentrate in the processing of nori-like can increase the nutritional value of nori-like, with 12.77% water content, 14.53% ash, 17.02% protein, 5.88% fat, and 25.77% dietary fiber. The dominant amino acids in the selected nori-like were histidine, glutamic acid, and glycine. This product has an aw value of 0.59 and L, a, b values of 14.28, 0.76, and 14.44, respectively.
Keyword: nori-like, Ulva lactuca, boiled water

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model