Judul: Merremia dennstedt ex endlicher (Convolvulaceae) in Sumatra.
Abstrak: Merremia is a small genus in the family Convolvulaceae. Merremia is a perennial or annual herb or woody liana with stems creeping or twinning on trees or rocks, put out milky white sap when injured and some species with tubers. Merremia is often confused with genus Ipomoea, due to they have resemblance in funnel shaped or campanulate corolla and straight anther. Phenetically, some members of Merremia have yellow flower whereas Ipomoea has white, purple or purplish white. Merremia is also confused with Operculina due both have non-spinulose pollen and dehiscent capsule. Nevertheless, Operculina characterized by circumciselli capsule and Merremia characterized by valve capsule. The important character in Merremia is the spread of the hairs on corolla that can be easily observed at the mature flower bud. The genus Merremia is found in the tropical regions of both hemispheres. Merremia wildly distributed throughout the tropical regions of Asia, Africa, Australia, North and South America and approximately there were 80 species of Merremia in the world. A Total of 175 sheets (164 collection numbers) which are deposited in Herbarium Bogoriense, 97 sheets (95 collection numbers) which are deposited Andalas University Herbarium (ANDA) and 9 sheets (4 collection numbers) which are deposited in BIOTROP Herbarium (BIOT) were studied. It composed of all specimens of Merremia in Sumatra. Additional specimens were collected by the author 28 sheets (15 collection numbers) from North Sumatra, West Sumatra and Lampung, which are stored in BO and BIOT. The digital data that consist of type specimens and distributions of species from JSTOR Plant Science and Convolvulaceae Unlimited were also used here. All the hebarium specimens were studied based on their morphological characters following de Vogel (1987) and Rifai (1976). The terminology of morphological characters followed Lawrence (1955), Veldkamp (1987), Harris and Harris (1994), Hickey and King (2005) and Stearn (1983). Information on the habitat, ecology, distribution, vernacular names and uses were noted from the specimens label and literatures. Taxonomic studies in Sumatra were conducted. There are eight species, one subspecies, one varietas and two forma from nine previously species (M. cissoides, M. dissecta, M. emarginata, M. hirta, M. peltata, M. quinquefolia, M. tridentata, M. tuberosa and M. vitifolia), two subspecies (M. umbellata ssp. orientalis and M. tridentata ssp. hastata), one varietas (M. boisiana var. sumatrana) and two forma (M. hederacea f. pubescens and M. hederacea f. barbata) can be recognized. One species (M. tridentata) and subspecies (M. tridentata ssp. hastata) are excluded because they have been proposed to different new taxa Xenostegia by Austin and Staples. The existence of M. emarginata was noted as new record in Sumatra and M. cissoides was noted as new record in Indonesia. A phylogenetic analysis using PAUP*4.Ob10 was undertaken based on morphological characters, using Evolvulus nummularius and Porana volubis as the out group. The phylogenetic analysis used 35 morphological characters was resulted consistency index (CI) = 0.60, homoplasy index (HI) = 0.40, retention index (RI) = 0.56 and Rescaled consistency index (RC) = 0.34. Phylogenetic tree used morphological characters divided taxa into two groups. The separation support M. boisiana var. sumatrana, M. cissoides, M.
Keyword: Convolvulaceae, Merremia, morphology, phylogenetic, Sumatra

Judul: Revisi Tetrastigma (Vitaceae) di Sumatera.
Abstrak: Tetrastigma merupakan kelompok liana dari suku Vitaceae yang dicirikan oleh adanya sulur yang tumbuh berhadapan dengan daun, tidak bercabang atau bercabang menggarpu, berdaun tunggal atau majemuk dengan jumlah anak daun bervariasi, mulai dari 3, 3−5, 5, hingga 7−(9)−(11) anak daun. Marga ini mempunyai bunga jantan dan betina yang berada pada individu berbeda (dioesis), putik bunga betina bercuping empat, dan potongan melintang endosperma berbentuk seperti huruf T atau M. Jenis-jenis Tetrastigma bermanfaat menjadi obat tradisional di Indonesia, Malaysia, Vietnam, Filipina, dan Cina. Tetrastigma dikenal sebagai satu-satunya inang Rafflesia, holoparasit yang menarik perhatian para turis. Sumatera merupakan jalur persebaran Tetrastigma dari Indocina ke kawasan Malesia. Namun, taksonomi Tetrastigma di Sumatera belum pernah dipelajari dengan rinci. Penamaan beberapa jenis Tetrastigma sering berganti, sehingga menimbulkan kerancuan. Kerancuan-kerancuan ini perlu diklarifikasi untuk memperoleh batasan jenis dalam marga Tetrastigma berdasarkan pengamatan ciri morfologi dan molekuler. Hasil pengamatan ini digunakan untuk pemutakhiran data keanekaragaman, status taksonomi dan penamaan, hubungan keserupaan antar jenis dalam Tetrastigma, serta pemetaan distribusi Tetrastigma di Sumatera. Prosedur penelitian mengikuti standar revisi, dan pengambilan sampel menggunakan metode jelajah flora. Seluruh bahan tumbuhan yang berjumlah 172 nomor koleksi, terdiri dari 113 nomor koleksi spesimen Herbarium Bogoriense, 53 nomor koleksi diperoleh dari kegiatan eksplorasi lapangan dan 6 nomor koleksi dari Kebun Raya Bogor telah diamati. Sebanyak 39 ciri morfologi digunakan dalam analisis hubungan keserupaan dengan koefisien simple matching menggunakan metode pengelompokan UPGMA (Unweighted Pair Group Method Average). Dua jenis primer DNA kloroplas, yaitu psbA−trnH dan trnL−F digunakan dalam analisis kekerabatan dengan metode Neighbor-Joining. Berdasarkan hasil penelitian teridentifikasi sebanyak 11 jenis Tetrastigma di Sumatera, yaitu Tetrastigma curtisii (Ridl.) Suess., T. dichotomum (Blume) Planch., T. diepenhorstii (Miq.) Latiff, T. dubium (Lawson) Planch., T. hookeri (Lawson) Planch., T. leucostaphylllum (Dennst.) Alston ex Mabb., T. papillosum (Blume) Planch., T. pedunculare (Wall. ex Lawson) Planch., T. pisicarpum (Miq.) Planch., T. pyriforme Gagnep., dan T. rafflesiae (Miq.) Planch.. Jenis-jenis Tetrastigma bervariasi pada ciri morfologi organ vegetatif dan generatif, serta dibedakan berdasarkan beberapa ciri morfologi, antara lain tipe permukaan batang, sulur, tangkai daun dan tangkai anak daun, jumlah anak daun, bentuk daun, bentuk pangkal, ujung dan tepi daun, keberadaan indumentum pada daun, tipe perbungaan, bentuk kuncup bunga, bentuk buah, dan bentuk potongan melintang endosperma. Analisis keserupaan dan kekerabatan dengan penanda morfologi dan molekuler membuktikan bahwa T. rafflesiae dan T. leucostaphylum, yang menjadi inang umum bagi Rafflesia di kawasan Malesia, adalah dua jenis yang berbeda. Jenis-jenis Tetrastigma di Pulau Sumatera ditemukan pada ketinggian 23−2200 m dpl, yang tersebar dari utara ke selatan hingga wilayah pulau-pulau iii kecil di sekeliling Sumatera. Persebaran setiap jenis dipengaruhi oleh beberapa faktor edafik dan iklim, seperti tipe batuan, curah hujan, serta perubahan tutupan lahan. Tetrastigma leucostaphylum merupakan jenis yang memiliki persebaran terluas di Sumatera.
Keyword: distribusi, psbA−trnH, Rafflesia, taksonomi, trnL−F

Judul: Implementasi Algoritme Enkripsi Advanced Encryption Standard secara Paralel dengan GPU NVIDIA CUDA
Abstrak: Processor streaming architecture in GPU has provide general purpose computation which have its own potential to help CPU with its parallel computation capability. One example of supported processor streaming architecture is Fermi which is developed by NVIDIA. Furthermore, NVIDIA has developed its own software development kit namely CUDA, which can integrate many popular existing programming languanges such as C++ for GPU-based parallel computation. This research focus on the implementation of parallel AES algorithm with GPU and analyze the performance result of the implementation in two different NVIDIA devices, namely NVIDIA GeForce GT220 and NVIDIA Quadro 600. In general, the performance of parallel GPU computation is better than sequential computation for large data input. It is obtained that the maximum speedup of NVIDIA GeForce GT220 in 8 MB input is 89.3 with 180% efficiency. Higher speedup of 101.6 can be obtained by NVIDIA Quadro 600 with the same input size with around 100% efficiency.
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