Judul: Record of Mole Crab (Hippa admirabilis) and Its Genetic Variation in Tomini Bay
Abstrak: Kepiting hippoid adalah kelompok crustacea yang menghuni daerah pantai berpasir. Terdapat 81 spesies kepiting hippoid yang telah diketahui di dunia yang terbagi menjadi tiga famili, yakni Albuneidae, Blepharipodidae dan Hippidae. Penelitian mengenai spesies undur-undur laut di Indonesia melaporkan terdapat 7 spesies yang ditemukan di Indonesia yakni, 6 spesies dari Famili Hippidae, dan satu spesies dari Famili Albuneidae. Spesies-spesies yang ditemukan di Indonesia memiliki data biologis yang masih sedikit, terutama pada data molekuler. Salah satunya adalah Hippa admirabilis Thalwittz, 1891 yang hanya memiliki data genetik dari Banggai, Sulawesi. Spesies ini telah dilaporkan ditemukan di Papua Nugini, Taiwan dan Pulau Sulawesi. Teluk Tomini, dipilih untuk tempat penelitian karena telah terdapat laporan H. admirabilis di Banggai, Sulawesi yang merupakan bagian dari Teluk Tomini. Teluk Tomini juga terpengaruh secara tidak langsung dari Arus Lintas Indonesia (Arlindo). Penelitian ini bertujuan untuk mencatat keberadaan H. admirabilis dan variasi genetik dari H. admirabilis di Teluk Tomini. Sampel diambil dari sepuluh koleksi spesimen Dr. Achmad Farajallah yang diperoleh dari daerah utara Sulawesi pada tahun 2016. Daerah sampling terdapat di Ogotumubu, Sulawesi Tengah dan Gorontalo, Provinsi Gorontalo. Identifikasi spesies dilakukan berdasarkan karakterisktik morfologi sampel. Konfirmasi spesies dilakukan dengan menggunakan gen CO1 sebagai DNA barcoding. Spesies ini baru pertama kali terekam jejaknya di Provinsi Gorontalo pada penelitian ini. Panjang gen CO1 yang berhasil diamplifikasi adalah sepanjang 596 pb. Sekuen yang diperoleh dibandingkan dengan sekuen penelitian sebelumnya di GenBank yaitu sekuen Hippa admirabilis dari Banggai, Sulawesi. Pohon filogeni menunjukkan bahwa semua sampel H. admirabilis tersusun menjadi satu klade. Empat haplotipe H. admirabilis dari Teluk Tomini ditemukan pada penelitian ini. Terdapat satu kelompok sharing haplotype dari Ogotumubu dan Gorontalo. Haplotipe lainnya merupakan haplotipe yang unik pada tiap lokasi. Perbedaan nukleotida antara Gorontalo, Ogotumubu dan Banggai adalah 8 basa nukleotida. Kata kunci: haplotipe, keragaman genetik, undur-undur laut
Keyword: haplotipe, keragaman genetik, undur-undur laut, haplotipe, keragaman genetik, undur-undur laut

Judul: Analisis Populasi Undur-Undur Laut Hippa adactyla Fabricius, 1787 (Crustacean: Hippidae) Berdasarkan Pendekatan Morfometrik dan Genetik di Pantai Berpasir Cilacap dan Kebumen
Abstrak: Mole crab (Hippa adactyla) lives in the intertidal zone of sandy beach ecosystems. Mole crab usually burries into substrate to cope with environmental stress. Indonesian coastal waters is one of the mole crab distribution area, especially families Hippidae, such as in the south coast of Central Java, especially in Cilacap and Kebumen sandy beach. Cilacap and Kebumen communities utilizing mole crab as bait fishing and food ingredients such as ‘rempeyek’. The samples was carried out on August 2014 at intertidal zone of Adipala sandy beach in Cilacap district and intertidal zone of Buluspesantren sandy beach in Kebumen district. Samples were caught using traditional fishing gear called ‘sorok’ along 3 km (1.5 km with one repetition). Total Hippa adactyla were 118 individuals which caught in Cilacap that consisted of 27 males (23%) and 91 females (77%); while 102 individuals that were caught in Kebumen consisted of 46 males (45%) and 56 females (55%). Carapace length to width ratio is above 1 in both population, it shows that the locomotion of H. adactyla is dominant in the vertical direction (backward locomotion). There were eight morphometric characters ratio that can be used as major factors to identify both populations based on discriminant analysis such as total length:carapace length (TL:CL), carapace width:carapace length (CW:CL), left and right coxa length:carapace length (LCo/RCo:CL), left merus length:carapace length (LM:CL), left and right propodus length:carapace length (LP/RP:CL), and left dactylus length:carapace length (LD:CL). Group centroid of morphometric characters in Cilacap (1.042) were separate to group centroid of morphometric characters in Kebumen (-1.205). 16S rRNA gene amplification of eight H. adactyla DNA by PCR machine at 450C annealing temperature. Composition of the nucleotide mtDNA 16S rRNA gene of H. adactyla shows rich of adenine (A) and thymine (T) (A-T rich). There are 54 mutations in the 16S rRNA gene between H. adactyla from Cilacap and Kebumen compared with H. adactyla (KF051307.1) from outside of Indonesia, consists of three sites of insertion, two sites of deletion, twenty nine sites of transition, and twenty sites of transversion. There are 26 specific sites on H. adactyla from Cilacap and Kebumen compared with H. adactyla from outside of Indonesia and Emerita talpoida (KF182557.1) data from GenBank. There is no genetic distance between species H. adactyla from Cilacap dan Kebumen that indicates there are estimated one population. Current pattern in Cilacap and Kebumen are important role in connectivity between H. adactyla from Cilacap and Kebumen.
Keyword: H. adactyla, discriminant analysis, 16S rRNA, Cilacap, Kebumen

Judul: Pembuatan Film Tipis Cu2ZnSnS4 sebagai Lapisan Penyerap Cahaya pada Sel Surya Menggunakan Metode Elektrodeposisi
Abstrak: Thin film of Cu2ZnSnS4 (CZTS) is an alternative semiconductor used as light absorber layer on solar cell. CZTS can replace silicon that commonly used as commercial semiconductor. The advantage of using CZTS as absorber layer is due to the abundance of its chemical composer on earth, and its high value of absorption coefficient. The absorber layer was made by using electrodeposition method on ITO glass substrates. The films were deposited at room temperature using potentiostatic mode with a potential of –1.05 V for 30, 45, and 60 minutes. After that, the films were annealed at two different temperatures, 180 ºC and 500 °C, for 45 minutes in N2/H2S atmosphere. Based on X-ray diffraction analysis, the polycrystalline thin film obtained fall into kesterite crystal phase. This type of crystal was obtained when the CZTS was annealed at 500 °C in H2S/N2 atmosphere. The value of optical band gap energy for the CZTS thin film was 2.2 eV with the film thickness about 1.228–6.366 μm. The sample of CZTS with electrodeposition time of 45 minutes and annealing temperature of 500 °C showed the best result and in conformity with absorber layers criteria for solar cells.
Keyword: semiconductor, ITO glass, CZTS thin film, electrodeposition