Judul: The determinant of an r-circulant matrix with entry a sequence of number
Abstrak: Matriks circulant adalah matriks yang entrinya bergeser satu kolom ke kanan secara berurutan, sehingga untuk mengetahui entri dari matriks circulant dapat dilihat dari kolom pertama. Entri bilangan dari matriks circulant dapat menggunakan entri berbagai bilangan, contohnya adalah bilangan Fibonacci dan bilangan Pell. Tujuan dari penulisan karya ilmiah ini adalah mengkaji secara teoritis perhitungan determinan matriks r-circulant dengan entri barisan bilangan. Diberikan matriks circulant ... dst
Keyword: r-circulant matrix, Fibonacci number, Pell number, determinant

Judul: Determinan dan Invers Matriks Circulant dengan Entri Barisan Aritmetika
Abstrak: Matriks circulant adalah matriks segi yang entrinya bergeser satu kolom ke kanan secara berurutan. Sehingga entri matriks circulant dapat dilihat dari satu kolom atau satu baris matriks tersebut. Salah satu sifat yang dimiliki matriks circulant, adalah bahwa inversnya juga bersifat circulant. Entri baris pertama suatu matriks circulant dapat diisi dengan berbagai bentuk barisan bilangan yang salah satunya adalah barisan aritmetika. Pada karya ilmiah ini diformulasikan secara eksplisit determinan dan invers matriks ... dst, Circulant matrix is a square matrix whose entry are shifted one column to the right sequentially. So the entry of a circulant matrix can be seen as one column or one row of the matrix. One of the property of a circulant matrix is the inverse also in the form of circulant. The first row of a circulant matrix can be filled in various type of sequence of numbers such as arithmetic sequence. In this research, the determinant and the inverse of a circulant matrix ... dst
Keyword: arithmetic sequence, circulant matrix, determinant, inverse

Judul: Durability of Specific Immunoglobulin (Ig) Y Againts Influenza and Covid-19 in Sunscreen
Abstrak: The benefit of specific immunoglobulin Y (Ig Y) as an active ingredient in personal care products such as sunscreen has not been properly studied. Our study aims to evaluate the reliability of specific IgY against influenza and the COVID-19 virus in a sample sunscreen product. Specific IgY influenza and COVID-19 viruses were inserted in the sample sunscreen at two concentrations of 0.1% and 0.25%. Three treatments were observed: control (C) sunscreen without IgY, treatment 1 (T1) sunscreen with 0.1% IgY, and treatment 2 (T2) sunscreen with 0.25% IgY. Organoleptic observations were carried out to monitor changes in aroma, color, and texture, and sunscreen sampling was done every week for 6 weeks. The durability of IgY was evaluated using an enzyme-linked immunosorbent assay (ELISA) and a neutralization assay. Organoleptic observation from weeks 1 to 6 showed consistency in its aroma, color, and texture. Enzyme-linked immunosorbent assay and neutralization assay (NA) results of the T1 and T2 groups showed negative results except for sample T1 at week 5, which showed a positive result in the Influenza A ELISA. Based on the results, it seems that IgY concentrations of 0.1% or 0.25% were not optimal. However, this negative result might be due to low concentration of the IgY and the presence of beeswax, which inhibits IgY and causes it to dissolve in distilled water, thus preventing it from being detected in the assay.
Keyword: Immunoglobulin Y, Sunscreen, Influenza, COVID-19, Biological Activity