Judul: Effectiveness of Rice Husks and  Sawdust as a Dry System Transport Media for Mud Crabs (Scylla serrata) in Brebes,  Central Java
Abstrak: Negara Indonesia memiliki luas mangrove 3,36 juta Ha. Jenis kepiting yang banyak hidup di mangrove tumbuh sampai dengan ukuran besar adalah kepiting bakau (Scylla serrata). Kepiting bakau masuk kedalam 10 komoditas yang tinggi permintaanya di dunia. Nilai produksi kepiting di Indonesia pada triwulan IV tahun 2022 sebesar 5.892 ton. Permasalahan yang sering terjadi dalam pengiriman kepiting hidup adalah tingginya angka kematian. Pemilihan media pengisi kemasan dalam transportasi kering penting untuk diperhatikan. Penelitian dilakukan dengan tujuan menganalisis pengaruh media pengisi yang berbeda terhadap kelangsungan hidup kepiting bakau (Scylla serrata) pada transportasi sistem kering. Transportasi dilakukan selama 12 jam, kemudian kepiting bakau diperlihara selama 14 hari. Penelitian ini menggunakan rancangan acak lengkap dengan satu kontrol dan dua perlakuan yaitu penggunaan media pengisi serbuk gergaji (SG) dan sekam padi (SP). Masing-masing dengan tiga kali ulangan. Wadah transportasi yang digunakan adalah styrofoam berukuran 34 × 25 × 30 cm. Wadah pemeliharaan pasca transportasi yaitu kontainer kepiting berukuran 20×15×10 cm. Kepadatan jumlah kepiting pada setiap kemasan adalah 9 ekor/box styrofoam. Kepiting yang digunakan berukuran 103,9 ± 8,6 gram. Hasil penelitian menunjukkan kelangsungan hidup kepiting bakau pada kemasan dengan media pengisi serbuk gergaji dan sekam padi selama transportasi sebesar 100±0% sedangkan pada kontrol 88,89±1%. Media pengisi serbuk gergaji lebih efektif dibandingkan perlakuan kontrol dan sekam padi dilihat dengan parameter uji pendukung lainnya., Indonesia has a mangrove area of 3.36 million hectares. The type of crab that lives in mangroves and grows to large sizes is the mangrove crab (Scylla serrata). Mangrove crabs are among the 10 commodities with the highest demand in the world. The value of crab production in Indonesia in the fourth quarter of 2022 is 5,892 tons. The problem that often occurs in shipping live crabs is the high mortality rate. It is important to pay attention to the choice of packaging filling media in dry transportation. The research was carried out with the aim of analyzing the effect of different filling media on the survival of mud crabs (Scylla serrata) in dry transportation systems. Transportation was carried out for 12 hours, then the mangrove crabs were kept for 14 days. This study used a completely randomized design with one control and two treatments, namely the use of sawdust (SG) and rice husk (SP) filling media. Each with three repetitions. The transportation container used is styrofoam measuring 34×25×30 cm. The post-transportation maintenance container is a crab container measuring 20×15×10 cm. The density of crabs in each package is 9/styrofoam box. The crab used measured 103,9 ± 8,6 grams. The results showed that the survival of mud crabs in packaging filled with sawdust and rice husks during transportation was 100 ± 0%, while in the control it was 88,89 ± 1%. The sawdust filler media was more effective than the control treatment and rice husks seen from other supporting test parameters.
Keyword: mud crab, sawdust, rice husk, dry transportation

Judul: Assessment of Wastewater Quality from Mud Crab (Scylla  sp.) Rearing
Abstrak: Limbah kegiatan pemeliharaan kepiting dapat meningkatkan jumlah nutrien di perairan, sehingga menyebabkan terjadinya eutrofikasi. Penelitian ini bertujuan menganalisis limbah hasil pemeliharaan kepiting bakau (Scylla sp.) dengan sistem kolam terpal. Penelitian dilaksanakan pada bulan September hingga November 2023. Rancangan penelitian menggunakan rancangan acak lengkap (RAL) dengan dua perlakuan (rucah dan pelet) dan 20 ulangan. Parameter yang dikaji dan dianalisis meliputi kualitas air, limbah hasil pemeliharaan, dan kondisi biologis. Hasil penelitian menunjukkan, kondisi kualitas air pada kedua media pemeliharaan sesuai dengan baku mutu pemeliharaan kepiting. Persentase limbah sisa pakan perlakuan pelet lebih sedikit yaitu 12% dari jumlah makanan total yang diberikan. Kondisi kualitas perairan dan sisa pakan mempengaruhi kondisi biologis kepiting. Kondisi biologis kepiting dengan perlakuan pelet memiliki nilai yang lebih baik dibanding rucah dengan nilai survival rate 95.50±1.54%, specific growth rate 1.39±0.63%, molting rate 5.5±5.10%. Perlakuan makanan berupa pelet memiliki kualitas air yang baik, jumlah sisa pakan lebih sedikit, dan lebih mendukung pertumbuhan kepiting bakau, namun kandungan amonia dan nitrat pada media pemeliharaannya tinggi., Waste from crab rearing activities can increase the amount of nutrients in the water, causing eutrophication. This study aims to analyze the waste from rearing mud crabs (Scylla sp.) with a tarpaulin pond system. The research was conducted from September to November 2023. The research design used a complete randomized design (CRD) with two treatments (crabs and pellets) and 20 replicates. Parameters studied and analyzed included water quality, waste from rearing, and biological conditions The results showed that the water quality conditions in both rearing media were in accordance with the quality standards for crab rearing. The percentage of waste left over from the pellet treatment was less at 12% of the total amount of food given. Water quality conditions and residual feed affect the biological condition of the crabs. The biological condition of crabs with pellet treatment has a better value than rucah with a survival rate value of 95.50 ± 1.54%, specific growth rate 1.39 ± 0.63%, molting rate 5.5 ± 5.10%. The pellet food treatment had good water quality, less feed residue, and was more suitable of mud crab growth, but the amonia and nitrate content of the rearing medium was high.
Keyword: mud crab, water quality, waste, rearing, crab food

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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