Judul: A Taxonomic Reinvestigation of some Biophytum Species (Oxalidaceae)
Abstrak: Biophytum merupakan salah satu tumbuhan yang dimanfaatkan sebagai obat tradisional di beberapa wilayah di Indonesia. Kesulitan mengidentifikasi sekumpulan koleksi Biophytum dari Jawa Barat dan Sulawesi Tengah, menunjukkan perlunya dilakukan penelitian untuk menemukan bukti taksonomi baru dalam merevisi marga Biophytum. Ciri dan sifat ciri morfologi dan anatomi Biophytum yang diamati terutama difokuskan pada ciri yang belum pernah dipergunakan sebelumnya untuk membatasi jenis-jenis Biophytum. Variasi ciri dan sifat ciri morfologi serta anatomi daun yang diamati dianalisis kemiripan dan perbedaannya. Data yang diperoleh kemudian ditabulasi untuk digunakan dalam membuat kunci identifikasi jenis Biophytum. Hasil penelitian menunjukkan bahwa terdapat variasi ciri morfologi pada bentuk permukaan dan warna batang, pelipatan daun muda, ada tidaknya lapisan lilin pada permukaan daun, pola perlekatan tangkai daun tua, keberadan adanya alat perkembangbiakan vegetatif berupa geragih dan tunas adventif, warna gagang perbungaan, warna calon perbungaan pada fase inisiasi, warna dan bentuk kuncup kecil dan kuncup besar, warna mahkota, diameter bunga saat mekar, bentuk dan ukuran buah merekah, serta bentuk biji. Pada ciri anatomi ditemukan variasi keberadaan macam dan letak trikoma, letak dan ukuran stomata, serta bentuk dinding sel epidermis. Semua variasi ciri dan sifat ciri morfologi batang, daun, bunga, buah dan biji, serta juga ciri anatomi daun ternyata dapat digunakan sebagai bukti taksonomi baru untuk membedakan jenis-jenis pada marga Biophytum melalui kunci identifikasi. Berdasarkan variasi ciri dan sifat ciri yang berhasil diungkapkan tersebut, ternyata bahwa kumpulan jenis yang diteliti ternyata terdiri atas lima jenis Biophytum yaitu, B. sensitivum, Biophytum sp. 1 dan Biophytum sp. 2 yang dikoleksi dari Sulawesi Tengah, serta B. dendroides dan B. reinwardtii yang berasal dari Jawa Barat., Biophytum is one of the sources of traditional medicinal herbs in several regions of indonesia. The difficulty in identifying collections of Biophytum from West Java and Central Celebes Province indicates that there is a need to find further taxonomic evidence for classifying species of this genus. Morphological and anatomical characters and character states hardly used in previous studies were analyzed and evaluated to find out their suitability to be used as diagnostic characters in defining each species. Information and data accumulated on the similarity and differences of morphological and leaf anatomical characters are tabulated and used to prepare an identification key. The results showed that there are variations in morphological characters of stem color and surface texture, the folding of young leaves, the presence of wax coating on leaf surface, attachment characteristics of old petioles, the presence of vegetative propagations in the form of stolon and adventive suckers, color and shapes of various generative parts including the peduncle, initial inflorescence and flower buds, size and shape of flowers, the dehiscing fruits, and the seed shapes. Similarly, there are variations in leaf anatomical characters such as the presence, shape, and distributions of trichomes and stomata, as well as the in the shape of epidermal cell walls. In conclusion, those variations in morphology of stem, leaves, flowers, fruits, and seeds, as well as leaf anatomical characters can be used as new taxonomic evidence to distinguish species of Biophytum. Based on the results obtained, it can be concluded that the collections studied represent five
Keyword: Biophytum, taxonomic evidence, morphological and anatomical characters

Judul: Karakteristik Morfologi dan Anatomi Beberapa Spesies dan Kultivar Begonia Serta Analisis Hubungan Kekerabatannya
Abstrak: The distinctive asymmetric leaf, fleshy jointed stem, and showy flower are several common characters belongs to genus Begonia. Indonesia has more than 200 species Begonia which spread in Java, Sumatera, Kalimantan, Sulawesi, and Papua islands. Morphological and anatomical characters can be used to identify, classify, and determine plants relationship. The aims of this research were to identify morphological and anatomical characters of 11 species and cultivars of Begonia and to determine their relationship. Nine species and cultivars were successfully identified, while two species could not be identified. Seven species were identified as B. acetosa, B. bowerae. B. listada, B. thelmae, B. semperflorens, B. maculata, and B. lepida, while two cultivars could be identified as B. Argenteo-Gutata “Fanfare” and B. “Orpha C. Fox”. Study on morphological characters of 11 species and cultivars obtained six similar characters including simple leaf, alternate leaf arrangement, asymmetric leaf blade base, axillary’s inflorescence, and unisexual flower. Based on paradermal section, there were individual stomata, stomatal cluster, and both individual and stomatal cluster in leaves of Begonia. Begonia listada had the smallest stomatal size (35.0 x 22.9 μm) while B. maculata had the biggest (46.7 x 30.4 μm). Begonia “Orpha C. Fox” had the lowest stomatal density (23.2/mm2), while Begonia sp. 1 had the highest (108.7/mm2). Observation on transversal section showed that B. lepida had the smallest leaf thickness (162.5 μm) while B. listada had the highest (433.3 μm). The results of hierarchical cluster analysis based on morphological, anatomical, or both characters showed different patterns of relationship.
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Judul: Approximation of the Median of Poisson Distribution Using the Relation of Poisson-Gamma Distribution
Abstrak: A major drawback of median is that median cannot usually be defined in closed form, even in the cases where their distribution functions are known. This study gives an approximation of the closed form for the median of the Poisson distribution by using the relation of Poisson-Gamma distribution. The approximation uses elementary techniques based on the monotonicity of certain sequences involving tail probabilities of the Poisson distribution and the Central Limit Theorem. Furthermore, a closed form expression for the mean absolute deviation 􀜧|􀜰􀰒 􀵆 􀜯􀝁􀝀􁈺􀜰􀰒􁈻| is also studied. The median is relevant because of the fact that it minimizes the mean absolute deviation of a Poisson random variable (􀜰􀰒􁈻 by considering median as central tendency.
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