Judul: Filogeografi Caridina sulawesi Spesies Grup (Crustacea: Decapoda: Atyidae)
Abstrak: Phylogeography study using mitochondrial DNA becomes popular to reveal spatial structuring among close related taxa of animals including the members of atyid shrimp. Caridina H. Milne-Edwards, 1837, the most diverse genus of the family Atyidae, faced a high extinction level especially for those endemic species with a limited range of distribution. Sulawesi Island holds the highest number of endemic species of the genus Caridina, both lacustrine and riverine species are inhabitants with unique distribution because many are restricted to certain areas. Based on several studies, in contrast, C. sulawesi has a wide distribution range from South to Central Sulawesi. However, their systematic status remains unclear due to lack of comprehensive analysis among the populations through genetic approach. This study provides the first molecular approach to reveal (i) the phylogenetic relationships, and (ii) genetic differentiation both intra- and inter populations of C. sulawesi and (iii) the relationship between spatial distribution and the geological processes of Sulawesi Island in the past. The samples were originated from seven localities covering the Central and South Sulawesi. A fragment of cytochrome oxidase subunit I (COI) with a final length of 781 bp was obtained from 36 individuals. A phylogenetic tree shows C. sulawesi to be monophyletic and contains of six different subclades with samples from South Sulawesi as a sister clade of the Central Sulawesi population. These two populations were separated by 10.2 to 11.3% genetic distance (K2P), and mostly correlated to the geographical region where the specimens were found. Caridina sulawesi specimens are potentially contained of two different species (cryptic), although they display sharing morphological characters. From the whole populations, a total of 21 haplotypes were found with moderate to high genetic diversity. The genetic variation was observed higher among the populations than within the populations, with high and significant FST indicated strong genetic structuring in C. sulawesi species group. The current distribution of the lineages of C. sulawesi can be explained by both large and small scales phylogeography. Long-distance dispersal as the result of ancestor life traits thus can expand their distribution. Furthermore, the geographical (mountain range) and ecological barriers (climate change) become barriers to the isolation of the C. sulawesi populations. The hidden diversity that might produce from the cryptic species emphasizes that the conservation efforts should place freshwater management strategies to prevent the population from decreasing through human activities., Studi tentang filogeografi menggunakan penanda DNA mitokondria menjadi populer untuk mempelajari penataan spasial pada kelompok taksa yang berkerabat dekat termasuk anggota udang air tawar famili Atyidae. Caridina H. Milne Edwards, 1837, genus dengan anggota spesies terbanyak, menghadapi tingkat kepunahan yang tinggi terutama untuk spesies endemik yang memiliki cakupan distribusi terbatas. Pulau Sulawesi memiliki jumlah spesies endemik udang Caridina paling banyak, baik spesies yang menghuni perairan danau maupun sungai dengan sebaran unik karena banyak yang terbatas pada daerah tertentu. Sebaliknya, C. sulawesi berdasarkan beberapa penelitian memiliki sebaran yang luas mulai dari Sulawesi Selatan hingga Sulawesi Tengah. Namun demikian, status C. sulawesi masih belum jelas karena belum pernah dilakukannya analisis komprehensif antar populasi dengan menggunakan pendekatan genetik. Penelitian ini menyajikan analisa molekuler pertama untuk mengungkap (i)
Keyword: Conservation genetics, freshwater shrimps, gene flow, landlock species, population genetics

Judul: The Diversity of Freshwater Shrimp in East Kalimantan
Abstrak: Udang air tawar tersebar luas di Indonesia, termasuk dalam anggota dari subfilum Crustacea dan ordo Decapoda. Udang air tawar yang banyak ditemukan di Indonesia adalah famili Atyidae dan Palaemonidae. Anggota famili Atyidae yang umumnya ditemukan dari genus Caridina, sedangkan anggota famili Palaemonidae yang umumnya ditemukan dari genus Macrobrachium. Informasi mengenai keanekaragaman udang air tawar di Kalimantan Timur belum dilaporkan sedangkan, kualitas perairan di Kalimantan Timur semakin menurun seiring dengan meningkatnya kegiatan ekploitasi sumber daya alam. Penelitian ini akan dimanfaatkan sebagai informasi dasar keanekaragaman jenis udang air tawar untuk masa depan sebelum terjadi perubahan lebih lanjut di wilayah Kalimantan Timur. Metode yang digunakan untuk identifikasi spesies dilakukan dengan mengunakan karakter morfologi dan diverifikasi menggunakan DNA barcoding. Pengamatan karakter morfologi dilakukan dengan kamera dan juga mikroskop stereo. Hasil pengamatan karakter morfologi yang ditemukan kemudian dibandingkan dengan kunci identifikasi dan deskripsi spesies udang air tawar. Analisis DNA barcoding dilakukan dengan tahapan ekstraksi, amplifikasi gen COI, elektroforesis, sekuensing DNA, dan pengolahan data menggunakan MEGA 11 dan mrBayes. Proses analisis data keragaman genetik gen COI antar populasi udang air tawar dilakukan dengan menggunakan DNAsp Penelitian ini melaporkan catatan Keanekaragaman Udang Air Tawar di Kalimantan Timur yaitu terdapat 11 spesies udang air tawar telah terkonfirmasi, famili Palaemonidae berjumlah tujuh spesies yaitu Marobrachium rosenbergii, M. lanchesteri, M. Scabriculum, M. mammillodactylus, M. sintangense, M. equidens dan M. villosimanus, sedangkan famili Atyidae berjumlah 4 spesies yaitu Caridina typus, C. peninsularis, C. gracilipes dan C. propinqua dari famili Palaemonidae. Serta ditemukan distribusi pada spesies M. sintangense di Kalimantan Timur dengan wilayah lain yaitu Jawa merupakan populasi yang berbeda. Populasi M. sintangense di Kalimantan Timur dan Thailand diketahui memiliki keterhubungan genetik, sementara berbeda secara genetik dari populasi di Jawa., Freshwater shrimps are widely distributed in Indonesia, belonging to the subphylum Crustacea and the order Decapoda. The most commonly found freshwater shrimps in Indonesia are from the families Atyidae and Palaemonidae. Members of the family Atyidae are generally found in the genus Caridina, while members of the family Palaemonidae are commonly found in the genus Macrobrachium. Information on the diversity of freshwater shrimps in East Kalimantan has not yet been reported, while the water quality in East Kalimantan continues to deteriorate due to increasing natural resource exploitation activities. This research will serve as baseline information on the diversity of freshwater shrimp species for the future before further changes occur in the East Kalimantan region. The method used for species identification involves morphological character analysis and verification using DNA barcoding. Morphological character observations were conducted with the help of cameras and stereo microscopes. The observed morphological characters were then compared with identification keys and descriptions of freshwater shrimp species. DNA barcoding analysis was carried out through the steps of extraction, COI gene amplification, electrophoresis, DNA sequencing, and data processing using MEGA 11 and MrBayes. Genetic diversity analysis of the COI gene among freshwater shrimp populations was performed using DNAsp. This study reports on the diversity of freshwater shrimp in East Kalimantan, confirming the presence of 11 species. The family Palaemonidae is represented by seven species: Marobrachium rosenbergii, M. lanchesteri, M. scabriculum, M. mammillodactylus, M. sintangense,
Keyword: Caridina, COI, distribution, genetic distance, Marobrachium

Judul: Sintesis BaTiO3 dari Campuran Ba(OH)2 dan TiO2 dengan Tambahan PbO
Abstrak: Piezoelectric material can generate electric field in response to applied mechanical stress. Conversely, they can stretch and contract in response to an electric field. This material can be used for many applications such as transducer, microphone, ultrasound, and pressure gauge. Barium titanate is a ferroelectric material with piezoelectric properties that can be synthesized easily. The aim of this study is to synthesis barium titanate from mixture of Ba(OH)2 and TiO2, also observe its optimum temperature and the effect of PbO addition. The method of synthesis was solid-state reaction and sol-gel method, then the products were characterized with x-ray diffraction (XRD). Based on XRD analysis, the optimum temperature for both methods was 800°C. Addition of PbO to BaTiO3 in the solid-state reaction formed a compound with formula of Ba1-xPbxTiO3. The addition has changed diffraction pattern peak at 2θ and strengthened its tetragonal structure. The best result was obtained at x of 0.5 which will form a compound of Ba0.5Pb0.5TiO3.
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