The development of technology enables the reduction of material size in science. The use of particle reduction in size from micro to nanoscale not only provides benefits to diverse scientific fields but also poses potential risks to humans and the environment. For the successful application of nanomaterials in bioscience, it is essential to understand the biological fate and potential toxicity of nanoparticles. The aim of this study was to evaluate the biological distribution as well as the potential toxicity of magnetic nanoparticles to enable their diverse applications in life science, such as drug development, protein detection, and gene delivery. We recently synthesized biocompatible silica-overcoated magnetic nanoparticles containing rhodamine B isothiocyanate (RITC) within a silica shell of controllable thickness [MNPs@SiO2(RITC)]. In this study, the MNPs@SiO2(RITC) with 50-nm thickness were used as a model nanomaterial. After intraperitoneal administration of MNPs@SiO2(RITC) for 4 weeks into mice, the nanoparticles were detected in the brain, indicating that such nanosized materials can penetrate blood-brain barrier (BBB) without disturbing its function or producing apparent toxicity. After a 4-week observation, MNPs@SiO2(RITC) was still present in various organs without causing apparent toxicity. Taken together, our results demonstrated that magnetic nanoparticles of 50-nm size did not cause apparent toxicity under the experimental conditions of this study.

This study demonstrates a simple and highly reproducible method for fabricating well-defined nanostructured polymeric surfaces with aligned nanoembosses or nanofibers of controllable aspect ratios, showing remarkable structural similarity with interesting natural biostructures such as the wing surface of Cicada orni and the leaf surface of Lotus. Our studies on the present biomimetic surfaces revealed that the wetting property of the nanostructured surface of a given chemical composition could be systematically controlled by rendering nanometer-scale roughness. The nanofabricating method we developed can be readily extended to other thermoplastic polymeric materials (e.g., light-emitting polymers, conducting polymers, block copolymers, liquid crystalline polymers), and it could be applied to developing a new generation of optical and electronic devices.

Although various scholars have researched issues regarding disaster management, few have studied the sharing and coordinating of information during disasters. Not much empirical data is available in this field and there is sparse insight into the factors that may impede or facilitate information sharing and coordination among stakeholders. In this paper, we provide an overview of the relevant obstacles and challenges by examining existing literature and then investigating a series of multi-agency disaster management exercises, using observations and a survey. Although all the people who took part in our study agree that sharing information is important, for the success of their own organization as well as the exercise as a whole, the extent to which information is actually being shared among organizations is often limited by a number of factors that can be attributed to the community, agency and individual level. We found that relief workers are often more concerned with receiving information from others than with providing information to others who may benefit. Incentives for sharing information, understanding each other's work-processes and the usability of information systems have shown positive effects on information sharing and coordination. The findings of our study have been formulated using six grounded propositions, which can be used by system designers and policy-makers upon validation in further research. We also provide directions for future research.

Cells in motion: Multifunctional nanoparticles, with a unique combination of magnetic and fluorescent properties, coupled with biocompatibility are prepared. The uptake of the magnetic nanoparticles by cells is investigated, and an external “magnetic motor effect” on the cells containing the nanoparticles is observed (see scheme).

Very efficient electrogenerated chemiluminescence (ECL) phenomena were realized by deliberately tuning electron-transfer reactions from electrochemically generated electron donor to metal complex radical cations. By controlling the relative positions of HOMO and LUMO levels (oxidation potential and reduction potential) of Ir(III) complexes, we could obtain 77 times higher ECL from iridium(III) complexes in the presence of TPA than that of the Ru(bpy)32+/TPA system. This high ECL efficiency of new Ir(III) complexes can be used in many interesting applications such as sensors and luminescent devices.

We studied the formation mechanism of hierarchical mesoporous silica nanoparticles with a wrinkle structure (wrinkled silica nanoparticles, WSNs), and a method for substructure control of silica nanoparticles was proposed. We confirmed that WSNs were generated in the bicontinuous microemulsion phase of the Winsor III system. By using the phase behavior of the Winsor III system, which depends on the water-surfactant-oil mixing ratio, and by adding various cosolvents, we could precisely control the structure of silica nanoparticles from the mesoporous to the wrinkle form; furthermore, we could control the interwrinkle distance.

Bone is a dynamic tissue that undergoes renewal throughout life by a process whereby osteoclasts resorb worn bone and osteoblasts synthesize new bone. Imbalances in bone turnover lead to bone loss and development of osteoporosis and ultimately fracture, a debilitating condition with high morbidity and mortality. Silica is a ubiquitous biocontaminant that is considered to have high biocompatibility. We report that silica nanoparticles mediate potent inhibitory effects on osteoclasts and stimulatory effects on osteoblasts in vitro. The mechanism of bioactivity is a consequence of an intrinsic capacity to antagonize activation of NF-κB, a signal transduction pathway required for osteoclastic bone resorption, but inhibitory to osteoblastic bone formation. We further demonstrate that silica nanoparticles promote a significant enhancement of bone mineral density (BMD) in mice in vivo providing a proof of principle for the potential application of silica nanoparticles as a pharmacological agent to enhance BMD and protect against bone fracture.

In recent years, there has been a great deal of research interest in fabricating superhydrophobic surfaces, which have static contact angles of water droplets greater than 150°, because of their importance in fundamental research [1,2] as well as in practical applications of biomimetic systems such as preventing the adhesion of snow or rain to antennas and windows, [3] producing stain-resistant textiles, [4] and wettabilityswitching surfaces. [5][6][7] The superhydrophobic property is believed to be governed by both the chemical composition of the surface material and the cooperative effect of nanostructures within the micrometer-scale areas (the so-called hierarchical structure). For example, the leaves of the lotus and taro and the wings of the cicada have superhydrophobic surfaces, [8][9][10][11] and they can undergo self-cleaning by removal of dust and pollutants using rolling water drops; this is usually called the "lotus effect". [5,9,10] Many researchers have generated artificial superhydrophobic surfaces by controlling the chemical composition of molecules, [12] polymers, [13][14][15][16] and metals [2,17,18] or by fabricating novel structures using various techniques such as spin-coating, [15] polymer imprinting, [19][20][21] self-assembly, [22] sublimation of a small molecule during gelation, [23] and etching techniques.[24] Although current fabricating techniques can generate some superhydrophobic surfaces, it is not easy to precisely control the nanostructures and microstructures within the hierarchical structures. Therefore, it would be worthwhile to develop fabrication methods that enable us to precisely and independently control the nanostructures and microstructures, in order to understand better the superhydrophobic phenomenon and to generate optimized biomimetic surfaces.We have developed a simple, efficient, and highly reproducible method of producing well-defined large-area nanostructured polymeric and metallic surfaces having nanoembossing or nanofibers with controllable aspect ratios by employing anodic aluminum oxides (AAOs) or a textured Al surface as a replication master. [19,25] As an extension of generating various nanostructures on the polymer surface, we have employed both photolithography and Al etching techniques to produce well-controlled micrometer-sized concave patterns on Al surfaces on which various nanostructures can be produced. From these combined techniques, hierarchical structures of templates can be precisely controlled at the micrometer scale as well as at the nanometer scale. On the basis of the heat-and pressure-driven imprinting process with thermoplastic polymers such as high-density polyethylene (HDPE), hierarchical polymer surfaces could be duplicated many times. The contact angle measurement of the water droplets on these surfaces clearly showed interesting cooperative effects of micrometerand nanometer-sized structures within the hierarchical structures to mimic water-repellent plant leaf surfaces. The fabrication process of biomimetic hierarchical surfaces compr...