Judul: Model Hasil Tegakan Jati Plus Perhutani Studi Kasus di KPH Madiun dan KPH Saradan
Abstrak: Jati Plus Perhutani (JPP) merupakan jenis jati unggulan yang diharapkan menggantikan jati konvensional yang daurnya relatif sangat panjang. Penyusunan model hasil tegakan JPP ditujukan untuk mengatur hasil tegakan JPP sesuai dengan kondisi tempat tumbuhnya. Model hasil tegakan JPP disusun dari 200 plot contoh yang tersebar di KPH Madiun dan KPH Saradan. Model hasil tegakan terbaik adalah Model Vanclay (1994) untuk menduga pertumbuhan diameter, bidang dasar, volume dan biomassa tegakan, sedangkan Model Clutter et al. (1983) untuk menduga pertumbuhan tinggi dan peninggi tegakan. Model di atas dianalisis dengan pendekatan regresi non-linear. Model Hasil tegakan JPP dapat digunakan untuk menentukan pertumbuhan tegakan JPP pada berbagai kualitas tempat tumbuh dan umur tertentu. Model Hasil tegakan JPP juga dapat digunakan untuk keperluan penetapan daur dan pengaturan hasil tegakan.
Keyword: non-linear regression, yield models, yield tables

Judul: Yield Models of Perhutani’s Teak Plus Plantation in KPH Balapulang and KPH Pemalang Regional Division of Central Java.
Abstrak: Jati Plus Perhutani (JPP) is a superior variety of teak that has been widely planted and spread in the Perum Perhutani area. The superior type of JPP is expected to replace the conventional teak, which has a very long rotation. This research aims to develop the yield models, and the yield table of JPP stands according to the quality class in which it was grown. The yield model was built based on sample plots that were spreadly ditributed, representing all growing conditions in KPH Balapulang and KPH Pemalang Perum Perhutani Regional Division of Central Java. Selection of the best yield model using non linear regression analysis. The best yield model for estimating growth in diameter, total height, over height, basal area, volume and stand biomass is the Vanclay model. This stand yield model is useful for determining the rotation and yield regulation and as a consideration in silvicultural actions so that the production of Perhutani’s Teak Plus wood can be optimal., Jati Plus Perhutani (JPP) merupakan varietas jati unggul yang sudah ditanam secara luas dan tersebar di wilayah Perum Perhutani. Jenis unggulan JPP diharapkan menggantikan jati konvensional yang memiliki daur sangat panjang. Penelitian ini bertujuan menyusun model hasil dan tabel hasil tegakan JPP sesuai dengan kelas kualitas tempat tumbuhnya. Model hasil dibangun pada plot contoh yang tersebar dan mewakili kondisi tempat tumbuh di KPH Balapulang dan KPH Pemalang Perum Perhutani Divisi Regional Jawa Tengah. Pemilihan model hasil terbaik menggunakan analisis regresi non linear. Model hasil terbaik dalam menduga pertumbuhan diameter, tinggi, peninggi, luas bidang dasar, volume dan biomassa tegakan adalah model Vanclay. Model hasil tegakan ini bermanfaat untuk penetapan daur dan pengaturan hasil serta sebagai pertimbangan dalam tindakan silvikultur agar produksi kayu Jati Plus Perhutani dapat optimal.
Keyword: Perhutani’s Teak Plus, rotation, stand yield model, stand yield tabel

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