Judul: Pembentukan rimpang mikro secara in vitro dan analisis kestabilan genetik antar sub-kultur  temulawak (Curcuma xanthorrhiza Roxb.)
Abstrak: Temulawak (Curcuma xanthorrhiza Roxb.) was used to be propagated from rhizome. High propagul weight will produce high yield. The use of big sized rhizome for seedling will reduce its use for consumption and processing purposes. Therefore, in vitro micro rhizome could be used as propagul alternative for the propagation of temulawak because of its simplicity and high multiplication in shorter time. Plantlet from repeated sub-cultures induced to form micro rhizome. High rate shoot multiplication caused somaclonal variation. In plants propagation, somaclonal variation was not desired because seed uniformity was very important. Therefore, genetic stability of plantlets for get true to type seed from the use of repeated sub-culture in vitro shoot for micro rhizome formation must be studied. This research used RFLP and sequencing method to find the genetic stability of plantlet among sub-cultures generations. RFLP method was used to mother plant’s DNA and plantlet’s DNA from 3rd, 4th, 5th and 12th sub-cultures. Sequencing analysis was used to mother plant’s and 12th sub-cultures plantlet DNA. In vitro micro rhizome formation research consisted of three studies : 1) The effect of physical of media (liquid and solid medium) and sucrose (30, 60, 90, 120 gL-1); 2) The effect of the strength of MS medium (half and full strength) and sucrose (30, 60, 90, 120 gL-1) ; 3) The effect of level of BAP (0, 1, 2, 3 mgL-1) and sucrose (30, 60, 90, 120 gL-1) to plantlet growth and micro rhizome formation. Cultures were incubated in the dark for 16 hours day-1. Electrophoresis band of DNA temulawak in RFLP analysis with restriction enzymes MBo1, Taq1 and Alu1 showed the same pattern between 5 samples DNA. There is possibility of genetic stability of temulawak plantlet between generation 3rd, 4th, 5th, and 12th sub-cultures and mother’s plants DNA. Homology result of sequencing DNA also showed genetic stability for 300 bp DNA. There is genetic sequence equality between DNA mother plants sequence at base number 61-361 and DNA plantlet 12th sub-culture at base sequence number 61- 361. Micro rhizomes of temulawak was formed in liquid half and full strength MS. Interaction BAP and sucrose have significant effect on rhizomes formation at 18 weeks after planting. The higher frequency of rhizomes formation was enhanced in medium with BAP 1 and 2 mgL-1 on sucrose concentration 60, 90, 120 gL-1. The increased of sucrose concentration also had positive effect to higher number, diameter and weight of micro rhizomes 8 weeks after acclimatization.
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Judul: Interaction of Genotype and Environment on The Phenolic Levels and Antioxidant Activity of Temulawak (Curcuma xanthorrhiza Roxb.)
Abstrak: Rimpang temulawak (Curcuma xanthorrhiza Roxb.) memiliki potensi sebagai sumber antioksidan karena terdapat senyawa bioaktif metabolit sekunder seperti senyawa fenolik. Perbedaan kondisi abiotik lingkungan, seperti air dan suhu, menyebabkan cekaman pada tanaman dan akan terbentuk variasi akumulasi metabolit sekunder tanaman. Penelitian ini bertujuan mengevaluasi produktivitas kadar fenolik dan aktivitas antioksidan serta mendapatkan informasi mengenai stabilitas genotipe rimpang temulawak pada kadar fenolik dan aktivitas antioksidan terhadap penanaman di tiga lokasi (Bogor, Cianjur, Sukabumi). Tahapan penelitian meliputi pengujian kadar fenolik dan aktivitas antioksidan metode DPPH serta daya adaptasi genotipe temulawak pada penanaman multilokasi dengan metode AMMI. Produktivitas kadar fenolik tertinggi diperoleh dari lokasi Sukabumi (7,8744 mg GAE/g), dan genotipe G5 (7,5394 mg GAE/g), sedangkan aktivitas antioksidan tertinggi diperoleh dari lokasi Cianjur (20,1519 μmol TE/g), dan genotipe G6 (21,1797 μmol TE/g). Keragaman lokasi berpengaruh nyata pada kadar fenolik, serta tidak terdapat interaksi genotipe dan lingkungan pada kedua parameter. Genotipe yang stabil pada ketiga lokasi adalah G2 untuk kadar fenolik, G3 dan G4 untuk aktivitas antioksidan, G1 dan G6 untuk kedua parameter, sementara G4 berpotensi stabil di Bogor untuk kadar fenolik., Temulawak rhizomes (Curcuma xanthorrhiza Roxb.) have the potentials as antioxidant sources because they contain bioactive secondary metabolites such as phenolics. Differences in environmental abiotic factors, such as water and temperature, cause stress on plants and will create variations in the secondary metabolites’ accumulations. This research aims to evaluate the phenolic levels productivity and antioxidant activity and to obtain information about the stability of temulawak rhizome genotypes on phenolic content and antioxidant activity on planting in three locations (Bogor, Cianjur, Sukabumi). The research stages included the phenolic content and antioxidant activity (DPPH method) test, as well as the adaptability of the temulawak genotype in multilocation planting using the AMMI method. The highest phenolic content productivity was obtained from Sukabumi (7.8744 mg GAE/g), and G5 (7.5394 mg GAE/g), while the highest antioxidant activity was obtained from Cianjur (20.1519 μmol TE/g), and G6 (21.1797 μmol TE/g). Location diversity has a significant effect on phenolic levels, and there is no interaction of genotype and environment on both parameters. The stable genotypes at all three locations were G2 for phenolic content, G3 and G4 for antioxidant activity, G1 and G6 for both parameters, while G4 was potentially stable only in Bogor for phenolic content.
Keyword: antioxidant, Curcuma xanthorrhiza, genotype, phenolics, stability

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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