Judul: Identification of Bacterial Isolates IR5 and IR9,  Relationships, Optimization of Media, and Synthesized Pigments
Abstrak: Bakteri isolat IR9 dan IR5 merupakan bakteri fotosintetik ungu yang biasa ditemukan di laut dan diketahui dapat menghasilkan pigmen. Isolat IR5 dan IR9 telah berhasil diisolasi dari laut. Penelitian ini bertujuan menganalisis kekerabatan antar kedua isolat tersebut berdasarkan sekuens 16S rRNA, mengoptimasi media pertumbuhan, dan mengidentifikasi jenis pigmen yang dihasilkan oleh kedua isolat tersebut. Analisis kekerabatan kedua isolat berdasarkan kemiripan sekuens 16S rRNA menunjukkan isolat IR5 dan IR9 tergolong ke dalam spesies Rhodovulum sulfidophilum. Kedua isolat tersebut diduga merupakan strain yang berbeda. Berdasarkan pengamatan secara kualitatif pada tingkat kepekatan warna kultur, isolat IR9 memiliki pertumbuhan yang lebih baik apabila dibandingkan dengan isolat IR5 pada media pertumbuhan yang sama. Komposisi media pertumbuhan yang paling optimum dan direkomendasikan untuk pertumbuhan isolat IR5 dan IR9 adalah 1% gula pasir + 0,5% NPK + 2,5% NaCl kasar. Media yang mengandung NPK mendukung pertumbuhan bakteri yang lebih optimum dibandingkan dengan media yang mengandung TSP tanpa NPK. Isolat bakteri IR9 mengalami pertumbuhan optimum pada hari ke-3. Identifikasi berdasarkan serapan panjang gelombang pada spektrofotometer UV-VIS menunjukkan bakteri tersebut mampu menghasilkan beberapa jenis pigmen, yaitu bacteriopheophytin, β-carotene, canthaxanthin, dan bacteriochlorophyll a.
Keyword: Identifikasi pigmen, kurva tumbuh, optimasi media, pohon filogenetik Rhodovulum sulfidophilum, Identifikasi pigmen, kurva tumbuh, optimasi media, pohon filogenetik Rhodovulum sulfidophilum

Judul: Characterization of Pigmented Actinobacteria through Several Polyphasic Taxonomic Approaches
Abstrak: Aktinobakteri berpotensi menghasilkan komponen metabolit sekunder salah satunya pigmen. Karakterisasi aktinobakteri berpigmen dapat dilakukan melalui pendekatan taksonomi polifasik. Aktinobakteri berpigmen yang dimiliki Laboratorium Mikrobiologi, Departemen Biologi FMIPA IPB diketahui dapat menghasilkan metabolit sekunder pigmen berkhasiat antioksidan. Namun, karakter dari isolat tersebut belum diketahui secara keseluruhan. Penelitian ini bertujuan mengkarakterisasi aktinobakteri berpigmen koleksi Laboratorium Mikrobiologi, Departemen Biologi FMIPA IPB melalui beberapa pendekatan taksonomi polifasik. Tahapan penelitian meliputi purifikasi, pertumbuhan dan karakterisasi morfologi koloni aktinobakteri pada berbagai media, kemampuan tumbuh pada berbagai sumber karbon, identifikasi gen 16S rRNA serta analisis bioinformatika. Lima isolat mampu tumbuh optimal pada media ISP 2. Morfologi koloni kelima isolat berbeda pada setiap media. Empat isolat termasuk genus Streptomyces, sedangkan satu isolat lainnya termasuk rare-actinobacteria non Streptomyces. Setiap isolat memiliki kemampuan tumbuh pada sumber karbon yang berbeda-beda. Hasil identifikasi molekuler gen 16S rRNA isolat HVB menunjukkan ukuran amplikon ~1465 pb yang memiliki kemiripan sebesar 91.62% dengan spesies Rhodococcus wratislaviensis strain G119. Kata kunci: aktinobakteri, molekuler, pigmen, rare-actinobacteria, taksonomi polifasik, Actinobacteria have the potential to produce secondary metabolite components such as pigment. Characterization of pigmented actinobacteria can be carried out using a polyphasic taxonomic approach. Pigmented actinobacteria belonging to the Microbiology Laboratory, Department of Biology FMIPA IPB are known to produce pigment secondary metabolites with antioxidant properties. However, the character of this isolate is not fully known. This research aims to characterize pigmented actinobacteria from the collection of the Microbiology Laboratory, Department of Biology FMIPA IPB through several polyphasic taxonomic approaches. The research stages include purification, growth and morphological characterization of actinobacterial colonies on various media, ability to grow on various carbon sources, identification of the 16S rRNA gene and bioinformatics analysis. Five isolates were able to grow optimally on ISP 2 media. The colony morphology of the five isolates was different on each medium. Four isolates belonged to the genus Streptomyces, while the other one belonged to rare-actinobacteria non-Streptomyces. Each isolate has the ability to grow on different carbon sources. The results of molecular identification of the 16S rRNA gene of HVB isolates showed an amplicon size of ~1465 bp which had a similarity of 91.62% to the species Rhodococcus wratislaviensis strain G119. Key words: actinobacteria, molecular, pigment, polyphasic taxonomy, rare actinobacteria
Keyword: actinobacteria, Molecular, pigment, polyfasic taxonomy, rare actinobacteria

Judul: Socioeconomic and psychological variables influencing household debt
Abstrak: The overall objective of this study was to examine factors influencing total debt, total debt payment, and patterns of debt payments. The study examined the impacts of both psychological (credit attitudes and perception of future income) and socioe- conomic variables on total debt, total debt payment and patterns of debt payments. A conceptual model for this study was developed by incorporating the theory of borrower risk, the economic and psychological economic theory of borrowing, and the results of previous studies. This model identifies socioeconomic and psycholog- ical variables that influence total debt, total debt payment, and patterns of debt payments. Socioeconomic variables included in the model are gender, race, mari- tal status, employment status, household size, age, education, and household assets. Psychological variables are credit attitudes toward the use of credit, and perception of future income. This study used data from the 1989 Survey of Consumer Finances. The survey was sponsored by the Federal Reserve in cooperation with some other federal agencies. Data for the survey were collected by the Survey Research Center at the University of Michigan between August 1989 and March 1990. dst ...
Keyword: Gender