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Marine mussels and barnacles are sessile biofouling organisms that adhere to a number of surfaces in wet environments and maintain remarkably strong bonds. Previous synthetic approaches to mimic biological wet adhesive properties have focused mainly on the catechol moiety, present in mussel foot proteins (mfps), and especially rich in the interfacial mfps, for example, mfp-3 and -5, found at the interface between the mussel plaque and substrate. Barnacles, however, do not use Dopa for their wet adhesion, but are instead rich in noncatecholic aromatic residues. Due to this anomaly, we were intrigued to study the initial contact adhesion properties of copolymerized acrylate films containing the key functionalities of barnacle cement proteins and interfacial mfps, for example, aromatic (catecholic or noncatecholic), cationic, anionic, and nonpolar residues. The initial wet contact adhesion of the copolymers was measured using a probe tack testing apparatus with a flat-punch contact geometry. The wet contact adhesion of an optimized, bioinspired copolymer film was ∼15.0 N/cm(2) in deionized water and ∼9.0 N/cm(2) in artificial seawater, up to 150 times greater than commercial pressure-sensitive adhesive (PSA) tapes (∼0.1 N/cm(2)). Furthermore, maximum wet contact adhesion was obtained at ∼pH 7, suggesting viability for biomedical applications.

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To highlight the societal burden of HBV infection in South Korea, we estimated the annual societal costs of HBV-related diseases for the year 2005. For the economic costs of HBV-infection-related diseases estimate, baseline data was collected from the Health Insurance Review and Assessment Service (HIRA) database. To complement data from the HIRA database, hospital charts from sample hospitals was reviewed and patient surveys were conducted. In 2005, the societal cost of HBV infection was 1.937 trillion KRW, including 474,642 million KRW of direct costs and 1.463 trillion KRW of indirect costs. The cost breakdown by disease was CHB at 465,167 million KRW, cirrhosis at 533,449 million KRW, hepatocellular carcinoma at 863,940 million KRW, and liver transplantation at 74,635 million KRW. The estimated amount is equivalent to 0.24% of the 2005 Korean GDP. This analysis emphasizes how important the prevention and treatment of these diseases are from the perspectives of the Korean society.

Nitrogen molecular species in several gas oils were analyzed by gas chromatograph with an atomic emission detector (GC-AED) and mass spectrometer (GC-MS). Nitrogen species in gas oils were divided through acidic extraction into basic species (such as aniline, quinoline, benzoquinoline, and their derivatives) and nonbasic species (such as indole, carbazole, and their derivatives). To be mostly identified, their distribution depended on the cutting point and origins of gas oils. Denitrogenation reactivities of nitrogen species in gas oils were followed in the hydrotreating reactions at 340 °C under 5MPa of H2 to quantify by GC-AED their respective reactivities in GOs. The reactivities orders and reactivity dependence on their chemical structures and matrix compositions are discussed on molecular bases. The reactivity order was found as indole > methylated aniline > methylated indole > quinoline > benzoquinoline > methylated benzoquinoline > carbazole > methylated carbazoles. The number and position of methyl groups were very influential on the reactivities of carbazole derivatives. Methyl groups neighboring the N atom inhibited remarkably the HDN reactions. Comparison of the reactivities of the same species in the GOs must be discussed by taking account of all components and products in the respective oil.

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We report a novel thin film polarizer fabricated from a photocurable lyotropic chromonic liquid crystal (LCLC) solution. An organicbased photocurable solution having a lyotropic liquid crystalline phase was prepared by dissolving 25-35 wt% of basic chromonic dye in an acidic monomer (acrylic acid) solution. The shear-coated film after UV irradiation exhibited the maximum polarization efficiency, P ¼ 95.2%. Compared to the conventional aqueous-based technique, the new method provided many advantages such as outstanding coating processibility, high thermal stability, good solvent resistance, moderate surface hardness, and excellent adhesion to various substrates, especially on a plastic substrate.