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"A study on the structure of the gonad of Fluta alba was made in the Laboratory. Data concerning the sexuality and body length showed that the smallest female and male recorded were 17.6 and 21.1 cm respectively. It was also found that smallest intersexes were 25 to 29.9 cm. One of the intersexual eels collected had the longest body length, i.e. 64.4 cm. Histological evidence showed that the change of the gonad from female to male were usually found after the lost of ovarian tissues and of proliferation of the interstitial cells in the inner zone of the gonadal lamella. At the same time the formation of the testicular lobules occured by proliferation of spermatogonia. The karyotype of Fluta alba exhibited six pairs (12 chromosomes) and all chromosomes were metacentric. There were no differences in number and morphological structures of chromosomes among sexes, therefore it is suggested that the change of the gonadal function in F. alba is not a genetically inherited, but it might be due to the hormonal regulations produced by the gonad."

"The objective of the experiment is to describe the influence of common carps hypophysis extract administration on gonad development of female tropical eel , Anguilla bicolor bocolor...."

"This book offers an in-depth analysis of the cell biology of cyanobacteria, a group of phototrophic microorganisms performing an important function in the biosphere. The chapters present the author’s and her colleagues’ pioneering investigations of the ultrastructure of cyanobacteria under high-light and dark conditions, during irradiation by extremely high fluxes of light, in the course of L-transformation and within model associations and natural symbioses with plants. Diverse patterns of ultrastructural change are illustrated in electron micrographs and schematics. The book further introduces a new concept of “bacterial ultrastructural plasticity” - the reversible rearrangement of ultrastructure in response to environmental changes, as a strategy for finding and investigating cell adaptation mechanisms and intraspecies structural diversity of cyanobacteria and other prokaryotes."

"The purpose of this experiment is to study the influence of 10% carbomide peroxyde and 0.4% stannous fluoride application on the crystallic of hydroxypatite in tooth enamel, by using x-ray diffraction method. Hydrogen peroxide solution and distilled water are used as control. The materials are applied for X hours in an incubator with 37"C and 100% humidity, for total 192 hours. The crystallite size and the lattice parameters are calculated from x-ray diffraction pattern, and the structure was then refined by Rieiveld analysis. lt can he concluded that carbamide pcroxyde and stannous fluoride do not influence neither the crystallic size of tooth enamel nor the lattice parameters, but they influence the micro strain in crystal. The X-ray diffraction on Ihc facial surface of enamel shows preferred orientation pattern at |002]."

"Pemanasan global dan krisis energy telah mendorong manusia untuk menemukan cara mangatasinya. Pengurangan konsumsi bahan bakar fosil dan penerapan green technology berkembang pesat saat ini. Pada kapal telah diteliti dan ditemukan cara untuk mengurangi hambatan seperti penggunaan microbubbles, surfactant, dan polymer. Penggunaan bahan surfactant dan polymer sentesis yang berbasiskan rantai karbon yang terbukti mampu mengurangi hambatan kapal. Namun penggunaannya memiliki dampak buruk terhadap lingkungan, sehingga beberapa polimer alam (biopolymer) mulai dikembangkan seperti getah karet latex dan kulit ikan hiu yang menurut hasil penelitian mampu mengurangi hambatan pada kapal. Pada penelitian ini digunakan lender kulit belut (Monepterus Albus) yang ditempelkan sepanjang 25% dan 20% panjang kapal pada bagian haluan kapal model. Metode yang dilakukan adalah melakukan pengujian tarik kapal model pada kolam dengan variasi kecepatan melalui pengaturan voltase yaitu 75V, 85V. Pengujian tarik dilakukan untuk mengetahui besarnya hambatan total kapal model kondisi tanpa penempelan kulit belut. Dengan melakukan perbandingan maka akan diketahui seberapa besar pengaruh penempelan kulit belut terhadap pengurangan hambatan total kapal model. Dari hasil penelitian diketahui bahwa kulit belut berpengaruh terhadap pengurangan hambatan kapal model pada saat kecepatan kapal model lebih besar dari 0,85m/s.

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Global warming and energy crisis has prompted people to find ways to overcome them. Reducing fossil fuel consumption and application of green technology thriving today. On the ship has been investigated and found ways to reduce barriers such as the use of microbubbles, surfactant, and polymer. The use of surfactants and polymer materials based on carbon chain sentesis which proved capable of reducing barriers to the ship. However, its use has an adverse impact on the environment, so some natural polymers (biopolymer) began to be developed such as latex rubber, latex and leather shark which, according to research results to reduce barriers to the ship.

In this study be used eel skin mucus (Monepterus Albus), which posted a 25% and 20% length of the ship model. The method is carried out tensile tests on the model boat pond with a variation of speed through the voltage setting is 75V, 85V. tensile testing conducted to determine the resistance of the total ship model at a certain speed, then compared with total resistance vessel model without annealing conditions eel skin. By doing a comparison would show how much influence eel skin sticking to reduction in total resistance model ships. From the research result shows that eel skin effect on the reduction of barriers at the speed of the ship model is larger than 0.85 m/s."

"The chromosome is a set of DNA structure that carry information about our life. The information can be obtained through Karyotyping. The process requires a clear image so the chromosome can be evaluate well. Preprocessing have to be done on chromosome images that is image enhancement. The process starts with image background removing. The image will be cleaned background color. The next step is image enhancement. This paper compares several methods for image enhancement. We evaluate some method in image enhancement like Histogram Equalization (HE), Contrast-limiting Adaptive Histogram Equalization (CLAHE), Histogram Equalization with 3D Block Matching (HE+BM3D), and basic image enhancement, unsharp masking. We examine and discuss the best method for enhancing chromosome image. Therefore, to evaluate the methods, the original image was manipulated by the addition of some noise and blur. Peak Signal-to-noise Ratio (PSNR) and Structural Similarity Index (SSIM) are used to examine method performance. The output of enhancement method will be compared with result of Professional software for karyotyping analysis named Ikaros MetasystemT M . Based on experimental results, HE+BM3D method gets a stable result on both scenario noised and blur image.Kromosom adalah kumpulan struktur DNA yang membawa informasi makhluk hidup. Informasi yang dapat diperoleh dengan proses Kariotyping. Proses ini membutuhkan citra yang jelas sehingga kromosom dapat dievaluasi dengan baik. Preprocessing harus dilakukan pada citra kromosom melalui penajaman citra. Proses ini dimulai dengan menghapus latar belakang citra. Langkah berikutnya ialah penajaman citra menggunakan metode image enhancement. Makalah ini membandingkan beberapa metode untuk peningkatan citra. Kami mengevaluasi beberapa metode dalam peningkatan gambar seperti Histogram Equalization (HE), Contrast-limiting Adaptive Histogram Equalization (CLAHE), Histogram Equalization with 3D Block Matching (HE+BM3D), dan unsharp masking. Penulis mengevaluasi dan membahas metode terbaik untuk meningkatkan citra kromosom. Oleh karena itu, untuk mengevaluasi metode, gambar asli dimanipulasi dengan penambahan beberapa kebisingan dan blur. Peak Signal-to-noise Ratio (PSNR) and Structural Similarity Index (SSIM) digunakan untuk mengukur kinerja metode. Hasil penajaman dari metode-metode yang dievaluasi akan dibandingkan dengan hasil software profesional untuk analisis kariotipe bernama Ikaros Metasystem T M . Berdasarkan eksperimen diperoleh hasil bahwa HE + BM3D merupakan metode yang paling stabil pada kedua skenario baik citra mengandung noise maupun citra yang kabur."

"Telah diketahui bahwa deformasi plastis pada temperatur tinggi dapat meningkatkan sifat mekanis dari logam. Peningkatan sifat mekanis ini disebabkan oleh pengendalian struktur mikro. Sifat mekanis yang dihasilkan dipengaruhi oleh ukuran butir ferrit yang terbentuk. Pada penelitian kali ini dilakukan proses termomekanik terhadap baja HSLA A572 untuk mengetahui pengaruh besar reduksi pada temperatur tinggi terhadap distribusi ukuran butir ferrit.Didapatkan bahwa ukuran butir ferrit pada bagian ketebalan memiliki nilai yang berbeda. Perbedaan ukuran antara permukaan atas dan bawah tidak memiliki nilai yang sangat signifikan terhadap nilai kekerasan. Sementara itu ukuran butir bagian tengah pada dimensi ketebalan sampel memiliki nilai yang paling rendah untuk setiap variasi besar reduksi.

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It has been known that plastic deformation at high temperatures could increase the mechanical properties of a metal. Improved mechanical properties is due to the microstructure control. The resulting mechanical properties is influenced by the ferrite grain size. In the present study thermomechanical process was performed on A572 HSLA steels to investigate the influence of hot roll reduction at elevated temperature to the ferrite grain size distribution.

It was found that the ferrite grain size on the thickness has a different value for each position. Difference in size between the upper and lower surfaces have no significant value to the value of hardness properties. While the grain size at the center of the sample thickness dimension has the lowest value for any of the variation reduction."