Judul: Leaf morphology and Anatomy Characters of Some Sansevieria Species
Abstrak: Penelitian ini bertujuan untuk mengkaji karakter morfologi dan anatomi daun pada lima spesies tumbuhan Sansevieria. Berdasarkan pengamatan karakter morfologi, dijumpai variasi morfologi daun meliputi ukuran panjang, lebar dan tebal daun serta pola warna pada daun ke lima spesies Sansevieria. S. sufruticosa memiliki daun berbentuk silindris berwarna hijau, dengan ujung daun berduri merah kecoklatan. S. masoniana congo memiliki daun berbentuk jorong, warna hijau tua, dengan tepi daun berwarna merah. S. samurai dwarf memiliki daun berwarna hijau dengan permukaan cekung membentuk saluran. S. trifasciata gold flame memiliki daun berbentuk lanset, tebal berwarna hijau tua bergaris hijau muda dengan tepi daun berwarna kuning, sedangkan S. kirkii brown memiliki daun berbentuk lanset, berwarna coklat dengan bercak putih, permukaannya bergelombang. Pada ke lima spesies Sansevieria daun dilapisi selapis epidermis berbentuk poligonal dengan 4 hingga 6 sisi yang berdinding tipis, kecuali spesies S. samurai dwarf sel epidermis berdinding tebal merata. Stomata dijumpai pada kedua permukaan daun, terdapat lebih banyak pada permukaan bawah daun (abaksial). S. masoniana congo memiliki stomata berukuran (panjang x lebar) terbesar, sedangkan S. kirkii brown memiliki stomata terkecil. S. masoniana congo memiliki kerapatan stomata terkecil dengan indeks stomata terbesar, sebaliknya S. sufruticosa memiliki kerapatan stomata terbesar dengan indeks stomata terkecil. Diantara kelima spesies yang diteliti, daun S. masoniana congo memiliki kutikula yang paling tebal sebaliknya S. trifasciata gold flame memiliki kutikula paling tipis., This research aims to describe leaf morphology and anatomy characters of five Sansevieria species. Based on the morphology characters, there are some variation in the length, width, thickness and leaf color pattern. S. sufruticosa has green cylindrical leaf, with auburn thorny leaf tip. S. masoniana congo has elliptical leaf, dark green with red stripe on the leaf margins. S. samurai dwarf has green leaf blade with concave surface forms thick wide channel. S. trifasciata gold flame has thick lanceolate leaf, light green striped dark green with yellow stripe in the leaf margin, while S. kirkii brown has white spotted brown lanceolate leaf with wavy surface. Sansevieria was leaf covered with a layer of epidermis. Epidermal cells are polygonal in shape with four to six thin wall sides, except S. samurai dwarf with thick cell wall. Stomata were found on both leaf sides, more stomata present on the lower epidermis than the upper epidermis. S. masoniana congo has the biggest (length x width) stomata, while S. kirkii brown has the smallest stomata. S. masoniana congo has the lowest stomatal density with the highest stomatal index, whereas S. sufruticosa has the highest stomatal density with the lowest stomatal index. Among all species, S. masoniana congo leaf has the thickest cuticula while S. trifasciata gold flame has the thinnest. Key words: Leaf anatomy, leaf morphology, Sansevieria, stomata
Keyword: Anatomi daun, morfologi daun, Sansevieria, stomata

Judul: Leaf Anatomy Diversity of Several Chili Species (Capsicum  spp.)
Abstrak: Cabai (Capsicum spp.) merupakan tanaman herba famili Solanaceae dari benua Amerika yang tumbuh di dataran rendah sampai tinggi. Struktur anatomi daun memiliki keanekaragaman yang tinggi. Penelitian ini bertujuan menganalisis struktur anatomi daun dari empat spesies cabai. Sampel daun yang digunakan yaitu Capsicum annuum, Capsicum baccatum, Capsicum chinense, dan Capsicum frutescens. Daun disayat paradermal dengan metode whole mount dan transversal dengan metode parafin. Karakter yang diamati berupa bentuk sel epidermis, tipe, ukuran, kerapatan, dan indeks stomata, tipe trikoma, tebal kutikula, tebal epidermis, tebal mesofil, tebal daun, serta susunan pembuluh. Hasil pengamatan menunjukkan bahwa sel epidermis berbentuk poligonal tidak beraturan serta terdapat stomata dan trikoma. Tipe stomata anisositik dan anomotetrasitik dapat dijumpai pada empat spesies. Tipe stomata anomositik hanya terdapat pada C. frutescens, sedangkan parasitik hanya pada C. annuum. Stomata terpanjang ditemukan pada C. annuum, sedangkan stomata terlebar ditemukan pada C. baccatum. Nilai kerapatan dan indeks stomata tertinggi sisi adaksial ditemukan pada C. annuum, sedangkan sisi abaksial dijumpai pada C. chinense. Trikoma kelenjar dan non-kelenjar dijumpai pada empat spesies. C. annuum memiliki tebal kutikula, tebal epidermis, tebal mesofil, dan tebal daun tertinggi. Pembuluh daun tersusun secara bikolateral., Chili (Capsicum spp.) is a herbaceous plant of the family Solanaceae from America that grows from low to high altitudes. The anatomical structure of leaves has a high diversity. This research aims to analyze anatomical structure of leaves from four chili species. Leaf samples used were Capsicum annuum, Capsicum baccatum, Capsicum chinense, and Capsicum frutescens. Leaves were sectioned paradermally using whole mount method and transversally with paraffin method. The observed characters were epidermal cell shape, type, size, density, and stomatal index, trichome type, cuticle thickness, epidermis thickness, mesophyll thickness, leaf thickness, and vessel arrangement. The results showed that the epidermal cells were irregularly polygonal and contained stomata and trichomes. Anisocytic and anomotetracytic stomatal types were found in four species. Anomocytic stomatal type was only found in C. frutescens, while paracytic was only found in C. annuum. The longest stomata was in C. annuum, while the widest stomata was in C. baccatum. The highest stomatal density and index value on the adaxial side was found in C. annuum, while the abaxial side was found in C. chinense. Glandular and non-glandular trichomes were found in four species. C. annuum had the highest cuticle, epidermis, mesophyll and leaf thickness. Leaf vessels arranged bicolaterally.
Keyword: anisocytic, bicollateral, paraffin method, Solanaceae, whole mount

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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