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Abstrak :
This book examines the environmental history of the Antarctic Peninsula region from the early twentieth century to the present. As the most politically contested part of the Antarctic continent, the Antarctic Peninsula region is a good location for considering the intersection of diplomatic history and environmental history. In making imperial claims to the Falkland Islands Dependencies, British officials argued that the production of useful scientific knowledge about the Antarctic environment helped to justify British ownership. In contrast, Argentines and Chileans made the case that the Antarctica Peninsula belonged to them as a result of geographical proximity, geological continuity, and a general sense of connection. Despite being caught up in the broader struggles between imperialism and nationalism of the mid-twentieth century, the Antarctic Peninsula region was never decolonized. Instead, under the terms of the 1959 Antarctic Treaty, existing sovereignty claims and reservations of rights were frozen for the duration of the treaty, and the whole Antarctic continent came to be governed by a treaty system that drew much of its authority from the production of useful scientific knowledge. In making an argument for imperial continuity in the history of the Antarctic Peninsula region, an environmental history approach offers a new perspective on the history of Antarctica that suggests that the environment, science, and politics continue to be closely entwined. This in turn has important implications for thinking about connections between diplomatic history and environmental history in different parts of the world and in addressing pressing global challenges such as climate change.

Abstrak :
Lipase B Candida antarctica (CALB) secara ekstensif dipelajari dalam produksi biodiesel, produk farmasi, deterjen, dan senyawa lainnya secara enzimatis. Salah satu kekurangan penggunaan CALB adalah suhu optimumnya yang relatif rendah pada 40oC (313 K). Tujuan penelitian ini adalah untuk merancang mutan CALB yang lebih termostabil dibanding CALB wild type dengan rekayasa penambahan ikatan disulfida. Simulasi dinamika molekul dilakukan untuk mengamati proses unfolding atau denaturasi termal CALB. Denaturasi termal CALB dipercepat dengan melakukan simulasi pada suhu tinggi. Simulasi dinamika molekul CALB dilakukan dengan perangkat lunak GROMACS pada suhu 300-700 K. Prediksi pasangan residu yang dapat dimutasi menjadi sistein dilakukan dengan perangkat lunak ?Disulfide by DesignTM?. Pemilihan residu yang dimutasi, didasarkan pada hasil analisis fleksibilitas CALB. Berdasarkan hasil analisis tersebut dirancang tiga mutan enzim CALB yaitu Mutan-1 (Leu73Cys/Ala151Cys), Mutan-2 (Trp155Cys/Glu294Cys), dan Mutan- 3 (Thr43Cys/Ser67Cys). Parameter yang digunakan untuk membandingkan termostabilitas enzim mutan dengan wild type adalah RMSD, SASA (solvent accessible surface area), jari-jari girasi (Rg), dan struktur sekunder. Simulasi dinamika molekul yang dilakukan pada ketiga mutan tersebut menunjukkan bahwa Mutan-1 memiliki termostabilitas yang lebih baik dibanding CALB wild type. Diharapkan hasil penelitian ini dapat memberikan saran rancangan mutasi yang dapat diimplementasikan ke dalam laboratorium basah (wet experiment). ......Candida antarctica lipase B (CALB) is extensively studied in enzymatic production of biodiesel, pharmaceutical products, detergents, and other chemicals. One drawback of using CALB is its relatively low optimum temperature at 313 K (40oC). The objective of this research is to design CALB mutant with improved thermostability by introducing extra disulfide bond. Molecular dynamic simulation was conducted to get better insight on the process of thermal denaturation or unfolding in CALB. Thermal denaturation of CALB was accelerated by conducting simulation at high temperature. Molecular dynamic simulation of CALB was performed with GROMACS software package at 300-700 K. Prediction of possible mutation was conducted using ?Disulfide by DesignTM? software. Selection of mutated residues was based on flexibility analysis of CALB. From those analyses, three mutants were designed, which are Mutant-1 (73LeuCys/151AlaCys), Mutant-2 (155TrpCys/294GluCys), and Mutant-3 (43ThrCys/67SerCys). Parameters that were used to compare the thermostability of mutant with wild type enzyme were RMSD, SASA (solvent accessible surface area), radius of gyration (Rg), and secondary structure. Molecular dynamic simulation conducted on those three mutants showed that Mutant-1 have better thermostability compared to wild type CALB. The resulted mutant design will be used as a suggestion to engineer CALB mutant in wet experiment.

Abstrak :
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