Judul: Metode Pengusangan Cepat dengan Larutan Etanol untuk Pengujian Vigor Daya Simpan Benih Caisin (Brassica rapa L. cv. grup Caisin)
Abstrak: The objective of this study was to obtain effective duration in accelerated aging method with soaking the seed in 20% liquid ethanol that can estimate vigor related to storability caisin seed during 3 and 6 months storage. There were five caisin seed lot used in this study. The seed were taken from five commercial seed with different initial vigor. This research was conducted in two separate experiments. The first experiment was conducted to study caisin seed that stored in aluminium foil pouches during 3 and 6 months period at storage room with temperature 23.3−29.9 °C and 61−85% relative humidity. The second experiment was conducted to study the effect from different duration soaking of the seed that has been moistened for 12 hours in liquid ethanol 20% for 30, 60, 90, 120, 150, and 180 minutes. Both of experiments were arranged in completely nested design. Germination of seed after soaking in 20% liquid ethanol for 90 minutes positively correlated with germination of seed after storage for 3 and 6 months with a coefficient of corellation 0.87 and 0.88. Both the coefficient of corellation close to 1 which shows that the germination of seed after soaking in 20% liquid ethanol can estimate vigor related to storability seed. Vigor related to storability caisin seed after 3 month can be predicted by the equation y = 56.04 + 0.36x with the coefficient of determination 77.00%. Vigor related to storability caisin seed after 6 month can be predicted by the equation y = 62.72 + 0.38x with the coefficient of determination 74.90%. Variable y indicates germination of caisin seed after storage while the variable x indicates germination of caisin seed after soaking in 20% liquid ethanol for 90 minutes.
Keyword: Bogor Agricultural University (IPB), viability, devigoration, deterioration

Judul: Pengujian Vigor Daya Simpan Benih Kubis (Brassica oleracea var. capitata L.) Menggunakan Metode Pengusangan Cepat dengan Etanol
Abstrak: The objective of this study was to obtain an effective soaking time on the accelerated aging method with liquid ethanol 20%, that can estimate vigor related to storability of 6 cabbage seeds after storage for 6 months. Cabbage seed consists of 6 commercial seed lots with different initial vigor, they were G1, MG, GC, GT, B3, and KC. The first experiment was storing seed for 6 months within aluminium foil packaging in the open storage room with temperature 23.329.9 C and 6185% relative humidity. The second experiment was rapid aging by soaking seeds in liquid ethanol 20% during 30, 60, 90, and 120 minutes. Index of vigor seed after soaking during 30 minutes had a closed correlation with germination of seed after storage for 6 months with a coefficient correlation 0.92, so that could be used to predicted vigor related to storability seed. Vigor related to storability cabbage seed after storage for 6 months could be predicted by the equation , with x indicated indeks of vigor seed after soaking in liquid ethanol 20% during 30 minutes, and coefficient determination (R2) was 83.8%.
Keyword: Bogor Agricultural University (IPB), viability, devigoration, deterioration

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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