Judul: Ecology Service Tumbuhan Herba untuk Lebah Trigona sp.
Abstrak: Herbaceous plants are able to flower any time, give them opportunity to interact with insects. This study aimed to analyze the diversity of pollen collected by Trigona sp. in herbaceous ecosystem and counted the percentage of pollen viability from the pollen basket. Trigona's nest was adapted at plot and the herbaceous plants with their pollen were identified. Pollen were took from hind legs at 07.00, 08.00 and 09.00 am. Pollen slide were make by acetolysis and SEM methods. Pollen were identified and examined of viability. Identification herbaceous plants and their pollen on plot showed that there were 7 herbaceous plants: Kyllinga monocephala, Cleome rutidosperma, Pennisetum polystachyon, Ageratum conyzoides, Brachiaria mutica, Cyperus orodatus, and Eleutheranthera ruderalis. Otherwise pollen which were collected by Trigona sp. consist of 11 kinds of pollen from 6 families, that were Sapindaceae, Leguminosae, Loranthaceae, Malvaceae, Symplocaceae, and unidentified family. Viability of pollen ranged from 88.8% to 99.8%. The result of identification herbacious plants and pollen that were taken by Trigona sp. indicated that there was not similarity therefore, it was no interaction between herbaceous plants in the plot with Trigona sp.
Keyword: Bogor Agricultural University (IPB), viability, Trigona sp, pollen, interaction, herbaceous plants

Judul: Exploration of Morphology, Time to Bloom, and Pollen Collected by Tetragonula laeviceps Bees in the Biopharmaca Gardens of IPB
Abstrak: Stingless bee atau lebah tanpa sengat Tetragonula laeviceps merupakan salah satu polinator yang efektif dalam penyerbukan. Stingless bee mendapatkan nektar atau polen dari berbagai jenis tanaman berbunga, termasuk tanaman obat yang juga membutuhkan polinator. Penelitian ini bertujuan mengeksplorasi karakter morfologi bunga, waktu bunga mekar di Unit Konservasi Budidaya Biofarmaka (UKBB) dan menganalisis hubungan antara karakter morfologi bunga dan mekarnya bunga dengan polen tungkai yang dikoleksi oleh lebah T. laeviceps dan polen pada madu. Metode yang digunakan yaitu pengamatan morfologi bunga, waktu bunga mekar dan identifikasi polen dari bunga yang mekar, tungkai lebah dan madu. Hasil penelitian menunjukkan T. laeviceps memperoleh polen dari 13 spesies tanaman yang mekar pada pukul 06.00-16.00 dengan ukuran bunga 1,21 ± 0,01 cm hingga 13,23 ± 0,01 cm. Bentuk mahkota bunga yang umumnya mekar yaitu tipe rotate dan salverform. Hasil analisis polen dari tungkai lebah diperoleh polen dari 9 spesies tanaman dari 6 famili berbeda. Sedangkan analisis polen pada madu diperoleh polen dari 23 spesies tanaman dari 18 famili berbeda. Terdapat 8 spesies tanaman obat berbunga yang ditemukan mekar di kebun Biofarmaka IPB dan juga ditemukan pada polen madu dan tungkai. Tanaman obat tersebut merupakan sumber pakan bagi T. Leaviceps antara lain, C. japonicum, C. hyssopifolia, C. pulcherrima, C. odorata, I. coccinea, J. multiflorum, P. guajava, dan T. diversifolia., Stingless bee Tetragonula laeviceps is an effective pollinator in pollination and affects the increase in crop production, including fruit and vegetable crops. Stingless bees obtain nectar or pollen from various flowering plants to produce honey, including medicinal plants requiring pollinators. This study aims to explore the morphological characters of flowers and the time of blooming in the Biopharmaceutical Conservation Unit (UKBB) and analyze the relationship between morphological characters of flowers and flower blooming with leg pollen collected by T. laeviceps bees and pollen on honey. The method used was the observation of flower morphology, flower blooming time, and pollen identification from blooming flowers, bee limbs, and honey. The results showed that T. laeviceps obtained pollen from 13 plant species that generally bloomed at 06.00-16.00 with flower sizes of 1.21 ± 0.01 cm to 13.23 ± 0.01 cm. The shape of the corolla of flowers that generally bloom are rotate and salverform types. The results of the analysis of pollen from bee limbs obtained 9 species from 6 different families. While the analysis of pollen from honey obtained 23 species from 18 different families. There are 8 species of flowering medicinal plants found blooming in the Biopharmaca garden of IPB and also found in honey and limb pollen. These medicinal plants are food sources for T. leaviceps including C. japonicum, C. hyssopifolia, C. pulcherrima, C. odorata, I. coccinea, J. multiflorum, P. guajava, and T. diversifolia.
Keyword: apertura, morfologi, polen, stingless bee, tanaman obat

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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