Immobilization of biomolecules in tailor-made nanometerscale structures can significantly improve the performance of biocatalytic processes. For efficient biocatalytic processes, it is highly desirable to develop nanostructured materials that enable high loading and long-term stability of the biocatalysts, as well as low mass-transfer resistance. In this regard, inorganic mesoporous materials [1] with well-controlled pore structures have gained much attention as appropriate, high-capacity hosts for biocatalysts. [2][3][4][5] Template synthesis has frequently been used to synthesize novel porous carbon materials.[6] Recently, a new class of nanoporous carbons, ordered mesoporous carbon (OMC), has been synthesized using ordered mesoporous silica materials as COMMUNICATIONS 2828

We report on antiferroelectriclike double polarization hysteresis loops in multiferroic HoMnO 3 thin films below the ferroelectric Curie temperature. This intriguing phenomenon is attributed to the domain pinning by defect dipoles which were introduced unintentionally during film growth process. Electron paramagnetic resonance suggests the existence of Fe 1+ defects in thin films and first principles calculations reveal that the defect dipoles would be composed of oxygen vacancy and Fe 1+ defect. We discuss migration of charged point defects during film growth process and formation of defect dipoles along ferroelectric polarization direction, based on the site preference of point defects. Due to a high-temperature lowsymmetry structure of HoMnO 3 , aging is not required to form the defect dipoles in contrast to other ferroelectrics (e.g., BaTiO 3 ).Recently, multiferroic (MF) materials have attracted a great deal of attention for their potential applications using the coupling between electrical 1,2 and magnetic properties. 3,4 Until now, the known coupling effects in most intrinsic MF materials were weak and observed mostly at low temperatures. This has motivated researchers to systematically tune the physical properties of the known MF materials, or to exploit artificial MF materials.Several groups have used the epitaxial stabilization technique, which employs a coherent interface strain between thin film and substrate, as a possible route to the exploitation of MF materials. For example, we fabricated hexagonal RMnO 3 (R = Gd, Tb, and Dy) epitaxial thin films and showed that their MF properties could be enhanced compared to those of their bulk perovskite counterparts. [5][6][7] Despite extensive efforts, numerous physical properties of the MF materials remain unclear. The artificially synthesized hexagonal RMnO 3 epitaxial thin films showed unexpected antiferroelectric (AFE)-like double polarization hysteresis (P-E) loops below room temperature. 5-7 Moreover, hexagonal HoMnO 3 (HMO) epitaxial thin films, whose bulk crystal structure is hexagonal, also showed the unusual AFE-like double P-E loops, 8 as shown in Fig. 1(a). This is rather unexpected because bulk HMO has an AFE phase at high temperatures between 875 and 1300 K and a ferroelectric phase below T C =875 K. 9 However, the origin for the double P-E loops has not been yet elucidated but inferred to be due to such effects as epitaxial strain, domain pinning, etc.Here, we discuss the physical origin of the double P-E loops observed in HMO thin films by performing electron paramagnetic resonance (EPR) measurements and first principles calculations. Our results support that the double P-E loops could be induced by domain pinning by defect dipoles (D defect ). Compared to other ferroelectrics, which usually have a

Although droplet microfludics is a promising technology for handling a number of liquids of a single type of analyte, it has limitations in handling thousands of different types of analytes for multiplex assay. Here, we present a novel "liquid-capped encoded microcapsule", which is applicable to various liquid format assays. Various liquid drops can be graphically encoded and arrayed without repeated dispensing processes, evaporation, and the risk of cross-contamination. Millions of nanoliter-scale liquids are encapsulated within encoded microcapsules and self-assembled in microwells in a single dispensing process. The graphical code on the microcapsule enables identification of randomly assembled microcapsules in each microwell. We conducted various liquid phase assays including enzyme inhibitor screening, virus transduction, and drug-induced apoptosis tests. The results showed that our liquid handling technology can be utilized widely for various solution phase assays.