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Highly dispersed Ru nanoparticles loaded on a TiO 2 support (Ru/TiO 2 (B)), which affects the hydrogenation of CO 2 to CH 4 (methanation), were prepared by employing a ''dry'' modification method using a barrel-sputtering instrument. The loaded Ru nanoparticles exhibited a narrow particlesize distribution with a mean diameter of ca. 2.5 nm. Methanation of CO 2 on the Ru/TiO 2 (B) catalyst produced a 100% yield at ca. 160 C, which is more than 200 C below that required for Ru/TiO 2 prepared by a conventional ''wet'' impregnation method. In addition, the methanation reaction over Ru/TiO 2 (B) proceeded at temperatures as low as room temperature with a reaction rate of 0.04 mmol min À1 g À1 .

Nanocasting of carbon replicas of siliceous micro-or mesoporous materials has gained a lot of interest during the last years. Micro-and mesoporous carbons, respectively, are, depending on their pore size, interesting materials for a wide range of applications, including hydrogen storage, doublelayer capacitors, molecular separation, and catalysis. Recently, the synthesis of highly ordered micro-and mesoporous carbons possessing a narrow pore size distribution has been described. [1,2] Here, mesoscopically ordered silica is impregnated with a carbon precursor, which is subsequently carbonized under non-oxidizing conditions. Porous carbons are finally obtained through dissolution of the silica framework. In order to maintain the structural integrity of the thus prepared carbon matrix, the host matrix should have an interconnected porosity. Thus, suitable zeolites, [3] MCM-48, [2,4] SBA-1, [5] mesocellular foams, [6] SBA-15, [7] and HMS [8] (hexagonal mesoporous silica) materials, which all possess a three-dimensional (3D) interconnected porosity, have been found to be suitable template structures. To date, however, most of the carbon materials reported have been obtained as powders, with only a few exceptions. [9] This fact may limit the applicability of these materials when macroscopic morphologies, such as chromatographic columns or membrane reactors, are required. The present communication is, to the best of our knowledge, the first to describe the preparation of monolithic carbon possessing a hierarchical bimodal meso-and macroporosity. In a series of papers, Nakanishi et al. [10] have described a sol±gel synthesis route to monolithic silica possessing a bimodal, hierarchical meso-and macroporous structure. This type of monolith is now commercially available as a chromatographic column under the brand name Chromolith. The key to the synthesis is to balance the kinetics of phase separation versus gelation of the silica under acidic conditions; this can be achieved by the use of either homo-polymers or block co- COMMUNICATIONS

Dedicated to Professor Dieter Fenske on the occasion of his 60th birthdayThe replication of nanoscale structures by a direct templating process has been used in recent years in several creative ways for the synthesis of carbon replicas of zeolites [1] or ordered mesoporous carbons, such as CMK-1 [2] or SNU-1. [3] Such processes rely on the fact that an ordered pore system, provided by the zeolite or ordered mesoporous silica, can be filled with a carbon precursor which is pyrolyzed and the silica leached with NaOH or HF solution. However, the technique is difficult to apply to the synthesis of framework compositions other than carbon, since the leaching of the silica typically also affects the material which is filled into the silica pore system. This problem could possibly be circumvented by not using the silica as the mold, but to instead go one step further and use the mesoporous ordered carbons as templates, which could then easily be removed by combustion or other techniques, as suggested recently. [4] On the macroscale, that is, for the production of photonic crystals, similar approaches are well known, where latex spheres are used as templates which can be removed by calcinations. [5] Also carbon black has been used as a ™template∫, for instance to synthesize mesoporous zeolite single crystals, in which the pores, however, are disordered. [6] In a first attempt to show the feasibility of using ordered mesoporous carbon to synthesize ordered mesoporous oxides, we decided to template mesostructured silica by using an ordered mesoporous carbon. Although this brings one only back to the starting point, that is, a mesoporous silica, it COMMUNICATIONS

Background-Bone-marrow mononuclear cell (BM-MNC) implantation improves ischemic symptoms in patients withcritical limb ischemia (CLI). The purpose of this study was to evaluate long-term clinical outcomes after autologous BM-MNC implantation in patients with CLI. Methods and Results-We assessed long-term clinical outcomes after BM-MNC implantation in 51 patients with CLI, including 25 patients with peripheral arterial disease (PAD) and 26 patients with Buerger disease. Forty-six CLI patients who had no BM-MNC implantation served as control subjects. Median follow-up period was 4.8 years. The 4-year amputation-free rates after BM-MNC implantation were 48% in PAD patients and 95% in Buerger disease, and they were 0% in control PAD patients and 6% in control Buerger disease. The 4-year overall survival rates after BM-MNC implantation were 76% in PAD patients and 100% in Buerger disease, and they were 67% in control PAD patients and 100% in control Buerger disease. Multivariable Cox proportional hazards analysis revealed that BM-MNC implantation correlated with prevention of major amputation and that hemodialysis and diabetes mellitus correlated with major amputation. In Buerger disease, ankle brachial pressure index and transcutaneous oxygen pressure were significantly increased after 1 month and remained high during 3-year follow-up. However, in patients with PAD, ankle brachial pressure index and transcutaneous oxygen pressure significantly increased after 1 month and gradually decreased during 3-year follow-up and returned to baseline levels. Conclusions-These