Judul: Persamaan Matematika Struktur Tegakan Horizontal Hutan Rakyat (Studi Kasus di Desa Parakanlima, Kecamatan Cikembar, Kabupaten Sukabumi, Jawa Barat).
Abstrak: Struktur tegakan horizontal adalah sebaran jumlah pohon persatuan luas (hektar) dalam berbagai kelas diameter. Pengelolaan hutan rakyat di Desa Parakanlima umumnya dilakukan dengan menggunakan sistem agroforestry. Penelitian ini bertujuan untuk memperoleh informasi bentuk persamaan matematika untuk struktur tegakan horizontal pada masing masing pemilik lahan hutan rakyat di Desa Parakanlima. Informasi ini diperlukan untuk memperoleh gambaran menggenai tingkat keteraturan pemanenan dengan pembinaan tegakan pohon pada setiap pemilik lahan hutan rakyat. Penelitian dilakukan di Desa Parakanlima, Kabupaten Sukabumi pada bulan Januari 2017 selama dua minggu. Hasil penelitian menunjukkan bahwa persamaan matematika yang dapat menggambarkan struktur tegakan horizontal pada hutan rakyat untuk setiap pemilik lahan di Desa Parakanlima adalah bentuk persamaan eksponensial negatif dan polinomial.
Keyword: hutan rakyat, persamaan matematika, struktur tegakan

Judul: Komposisi Jenis dan Persamaan Matematika untuk Struktur Tegakan Horizontal Hutan Rakyat di Desa Kalimendong
Abstrak: Stand structure can be used to identify the plantation characteristic. That is important for determining treatment of silviculture. This research purpose is to find out the information of mathematic equation in every private community forest in Kalimendong Village. This research was conducted in Kalimendong Village, Wonosobo Distrct in May 2014 (2 weeks). Data was collected using census method, where the measurement was done in every stands on private lands. Processed data was confined to dominating stands which is Sengon with 519 Sengon trees. Sengon’s variables is diameter and basal area presented in histogram. In order to explain more about stands distribution, data analyzed using normal distribution function. The result showed that the mathematic equation in every private land can be accepted with coefficient of determination (R²) more than 0.5 and p-value less than 0.05. Distribution form obtained from this research is polynomial function and negative exponential. Plantation characteristic specifically known from inverted bell curve but Sutarman and Waluyo land has inverted ‘’J’’ c
Keyword: Bogor Agricultural University (IPB), stands structure, mathematic equation

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