Sebelas Maret University

About: Sebelas Maret University is a education organization based out in Surakarta, Indonesia. It is known for research contribution in the topics: Population & Public health. The organization has 10901 authors who have published 10832 publications receiving 33057 citations. The organization is also known as: Universitas Negeri Surakarta & Universitas Sebelas Maret.

Investigation of structural performance subjected to impact loading using finite element approach: case of ship-container collision

Abstract: Abstract Transporting mass products from one country to others is essential activities in industrial cycle. Ships are selected as reliable carriers for this objective considering traveling time and operational cost. During its operational, accidental events such as storm, high tide and bad weather may cause the products which are usually packed in freight containers fall into sea, and impacts the ship structure. In this situation, casualties on both involved structures can be detrimental. This work analyzes a series of ship-container collision in maritime territory in order to investigate resulting structural phenomena. The finite element approach is selected to solve the designed collision cases where the discussion is directed to selected crash-worthiness criteria. Impact speed between ship and container structures is chosen as the main parameter in the designed scenario by judging whether this parameter is a good representative of sea state. Overall results indicate that the indication for container rebounding after impact was high. It was followed by a significant increment of the internal energy after higher velocity, which was more than 5 m·s−1, had been applied to the scenario. Quantification of specific structural performance suggests that approximately more than 80% of the damage occurrs on the contacted area of the container structure.

The Thioesterase Bhp is Involved in the Formation of β‐Hydroxytyrosine during Balhimycin Biosynthesis in Amycolatopsis balhimycina

Abstract: The putative hydrolase gene bhp from the balhimycin biosynthetic gene cluster has been cloned and overexpressed in Escherichia coli. The corresponding enzyme Bhp was purified to homogeneity by nickel-chelating chromatography and characterized. Although Bhp has sequence similarities to hydrolases with "haloperoxidase"/perhydrolase activity, it did not show any enzymatic activity with standard "haloperoxidase"/perhydrolase substrates (e.g., monochlorodimedone and phenol red), nonspecific esterase substrates (such as p-nitrophenyl acetate, p-nitrophenyl phosphate and S-thiophenyl acetate) or the model lactonase substrate dihydrocoumarin. However, Bhp could be shown to catalyse the hydrolysis of S-beta-hydroxytyrosyl-N-acetyl cysteamine thioester (beta-OH-Tyr-SNAC) with 15 times the efficiency of S-L-tyrosyl-N-acetyl cysteamine thioester (L-Tyr-SNAC). This is in agreement with the suggestion that Bhp is involved in balhimycin biosynthesis, during which it was supposed to catalyse the hydrolysis of beta-OH-Tyr-S-PCP (PCP=peptidyl carrier protein) to free beta-hydroxytyrosine (beta-OH-Tyr) and strongly suggests that Bhp is a thioesterase with high substrate specificity for PCP-bound beta-OH-Tyr and not a "haloperoxidase"/perhydrolase or nonspecific esterase.

Profil Keterampilan Argumentasi Ilmiah Mahasiswa Pendidikan Biologi FKIP UNS Pada Mata Kuliah Anatomi Tumbuhan

Abstract: Lemahnya argumentasi ilmiah mahasiswa dalam pembelajaran telah banyak menjadi perhatian, terutama dalam hal mengevaluasi dan mengkonstrak permasalahan dan solusinya. Penelitian ini bertujuan untuk mengetahui bagaimana profil keterampilan argumentasi ilmiah mahasiswa pada mata kuliah Anatomi Tumbuhan. Penelitian ini merupakan penelitian deskriptif untuk mendapatkan gambaran keterampilan argumentasi mahasiswa semester 3 di Prodi Pendidikan Biologi FKIP UNS melalui tugas tertulis yang diberikan. Penilaian argumentasi mahasiswa mengacu pada Toulmin’s Argumentation Pattern (TAP) yang memuat komponen claim, evidence, reasoning dan rebuttal . Hasil penelitian menunjukkan bahwa kemampuan argumentasi ilmiah mahasiswa Pendidikan Biologi FKIP UNS masih tergolong rendah, dibuktikan dengan skor rerata claim sebesar 52%, evidence sebesar 42%, reasoning sebesar 15% dan rebuttal sebesar 10%. Temuan ini akan dijadikan dasar bagi penelitian lanjutan mengenai model dan strategi pembelajaran inovatif yang dapat meningkatkan kemampuan argumentasi dan penalaran ilmiah terutama bagi calon guru biologi. Keywords: argumentasi ilmiah, Toulmin’s Argumentation Pattern