Judul: Pollen Morphology of Legume Plants in IPB University Campus, Dramaga
Abstrak: Tumbuhan berbunga menghasilkan polen dengan karakter morfologi yang bervariasi. Informasi mengenai polen dapat digunakan untuk identifikasi, penelitian genetika, sumber bukti taksonomi, serta perubahan evolusi pada tumbuhan. Penelitian ini bertujuan mendeskripsikan karakter morfologi polen yang berasal dari tumbuhan legum di kampus IPB, Dramaga. Pengamatan morfologi polen dilakukan terhadap 20 spesies tumbuhan dari famili Fabaceae. Pengambilan dan pengoleksian bunga dilakukan dengan metode jelajah di beberapa wilayah kampus IPB, Dramaga. Sediaan mikroskop sampel polen dibuat dengan metode asetolisis standar. Karakter morfologi polen yang diamati meliputi unit polen, bentuk polen dari sisi polar dan ekuatorial, indeks P/E, ukuran polen, tipe aperture, dan ornamentasi eksin. Hasil penelitian menunjukkan bentuk polen dari sisi polar dan ekuatorial pada sebagian spesies tumbuhan legum berupa circular dan circular oval. Ukuran polen yang diamati sangat bervariasi yaitu berukuran sangat kecil hingga sangat besar. Hasil pengukuran polen berdasarkan indeks P/E memiliki nilai >1,00. Tipe aperture yang dijumpai sangat bervariasi meliputi monoporate, tetraporate, tricolpate, tricolporate, dan triporate. Ornamentasi eksin yang ditemukan berupa psilate, reticulate, dan scabrate. Kata kunci: aperture, asetolisis, Fabaceae, ornamentasi eksin, ukuran polen, Flowering plants produce pollen with varied morphology characteristics. Pollen information can be used for identification, genetic research, taxonomic evidence sources, and evolutionary changes in plants. This study aimed to identify the pollen morphology characteristic of legume plants from the IPB campus, Dramaga. Pollen grains morphology observations were carried out on 20 species of the family Fabaceae. The collection and collection of flowers are carried out by the roaming method in several areas of the IPB campus, Dramaga. Pollen sample microscopy was prepared by the acetolysis standard method. The morphological characters of pollen grain observed were pollen unit, pollen shape from polar and equatorial view, P/E index, pollen size, aperture type, and exine ornamentation. The observations result showed that the pollen shape from the polar and equatorial of some species of legumes plant was circular and circular oval. The size of pollen grains varied greatly, from very small to very large sized. The results of the pollen measurement based on the P/E index had a value >1.00. The types of aperture found varied including monoporate, tetraporate, tricolpate, tricolporate, and triporate. Exine ornamentation is found in the form of psilate, reticulate, and scabrate. Keywords: acetolysis, aperture, exine ornamentation, Fabaceae, pollen size
Keyword: acetolysis, aperture, exine ornamentation, Fabaceae, pollen size

Judul: Variasi Morfologi Polen Beberapa Spesies Tanaman Pekarangan
Abstrak: Informasi mengenai keragaman polen sangat bermanfaat dalam menunjang berbagai disiplin ilmu. Karakter polen yang tahan terhadap pengaruh lingkungan maupun terhadap oksidasi selama proses fosilisasi dapat menjadi sumber data yang sangat penting. Data tentang polen banyak dipakai dalam ilmu forensik terkait investigasi pelaku tindak kriminal. Penelitian ini bertujuan mengidentifikasi variasi morfologi polen tanaman pekarangan. Sampel polen dari 22 spesies tanaman diambil dari 13 pekarangan rumah penduduk di kawasan Kota Pekanbaru dan satu spesies tanaman pekarangan diambil dari kampus IPB University, Bogor. Pengambilan bunga dilakukan berdasarkan jumlah spesies terbanyak dari suatu famili yang telah ditemukan. Pengamatan morfologi polen dilakukan terhadap 23 spesies tanaman dari famili Apocynaceae, Convolvulaceae, Cucurbitaceae, Oxalidaceae, dan Solanaceae. Sediaan polen dibuat dengan metode asetolisis standar. Karakter morfologi polen yang diamati adalah bentuk polen dari sisi polar dan ekuatorial, ukuran rata-rata polen, tipe aperture, dan tipe ornamentasi eksin. Hasil pengamatan menunjukkan bentuk polen dari sisi polar dan ekuatorial untuk seluruh spesies dari seluruh famili yaitu berupa circular dan circular oval. Ukuran rata-rata polen sangat beragam, mulai dari berukuran kecil hingga sangat besar. Tipe aperture tricolporate ditemukan pada famili Apocynaceae, Cucurbitaceae, dan Solanaceae. Famili Convolvulaceae tipe aperture berupa pantoporate, dan Oxalidaceae memiliki aperture tipe tricolpate. Tipe ornamentasi eksin berupa psilate ditemukan pada famili Apocynaceae, Cucurbitaceae, Oxalidaceae, dan Solanaceae, sedangkan famili Convolvulaceae bertipe echinate., Information about the diversity of pollen is very useful in supporting various disciplines. The character of pollen that is resistant to environmental influences and to oxidation during the fossilization process can be a very important of data source. Pollen data are widely used in forensic science related to criminal investigations. This study aimed to identify variations in the pollen morphology of garden plants. Pollen samples of 22 plant species were taken from 13 house gardens in Pekanbaru and one species of garden plant was taken from IPB University, Bogor. Flower collection is carried out based on the highest number of species from a family that has been found. Pollen grains morphology observations were carried out on 23 species belonging to the families Apocynaceae, Convolvulaceae, Cucurbitaceae, Oxalidaceae, and Solanaceae. Pollen slides were prepared by acetolysis standard method. The morphological characters of pollen grain observed were pollen shape from polar and equatorial view, pollen size, aperture type, and exin ornamentation. The result showed that pollen shape from the polar and equatorial view of all species was circular and circular oval respectively. The size of pollen grains were varied greatly, ranging from small to very large sized. The tricolporate aperture types were found in the Apocynaceae, Cucurbitaceae, and Solanaceae. The Convolvulaceae were pantoporate, and Oxalidaceae had a tricolpate type. Exin ornamentation in the form of psilate was found in Apocynaceae, Cucurbitaceae, Oxalidaceae, and Solanaceae, while in the Convolvulaceae was sculpturing echinate.
Keyword: acetolysis, aperture, exin ornamentation, polar and equatorial view, pollen size

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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