Nanostructured materials have attracted much attention because of their unique properties and potential applications in many fields. [1] In the last decade, significant progress in the synthesis of nanostructured materials with controlled size and morphology has been achieved. [2,3] One-, two-, or three-dimensional (1D, 2D, 3D) suprastructures assembled from preformed nanoparticles, [4] nanorods/wires and nanotube arrays, [5] nanostructured hollow spheres, [6] and mesostructured semiconductors have been successfully prepared. [7] In past research, amphiphilic molecules have usually been used either to direct nanoparticle aggregation or to form self-assemblies as templates for the fabrication of inorganic nanostructures. When self-assemblies of amphiphilic molecules are used as templates, the products are structurally and morphologically diverse because of the noncovalent interactions between the template molecules, such as hydrogen bonds, electrostatic interactions, van der Waals forces, and hydrophobic interactions, which lead to diverse inorganic nanostructures. [8][9][10] Using amphiphilic molecule assemblies such as vesicles, [11] microemulsions, [12] micelles, [13] and others [14,15] as templates, a variety of hollow inorganic nanostructures, which are usually spherical, have been prepared. In this paper, cubelike Co 3 O 4 nanoboxes, whose walls are constructed of a single layer of nanocrystals, are introduced. To the best of our knowledge, the only previously observed nanoboxes were constructed of noble metals and alloys, and most recently octahedral Cu 2 O nanocages with single crystalline walls have been generated. [16] Our synthesis is based on surfactant particles formed in alcohol solution and the fabrication of Co 3 O 4 nanoboxes using the separately dispersed cubelike particles as templates, which may provide a simple route to the synthesis of metal oxide nanoboxes. As an important magnetic p-type semiconductor, the spinel Co 3 O 4 has extensive applications in, for example, heterogeneous catalysis, solid-state sensors, electrochromic devices, solar energy absorbers, and as anode materials in Li-ion rechargeable batteries. Nanostructured Co 3 O 4 , including films, tubes, fibers, rods, nanocubes, and nanoaggregates, have been prepared to modify or promote its intrinsic properties.[17] Nanoboxes whose walls are constructed of Co 3 O 4 nanocrystals may have unique and interesting properties. The nanoboxes were obtained after the dispersion of Co(NO 3 ) 2 ·6H 2 O and sodium dodecylbenzenesulfonate (SDBS) in absolute ethanol was heated at 90°C for 8 h and then at 180°C for 3 h, followed by removal of the organics. The X-ray diffraction (XRD) pattern of the product indicates the spinel Co 3 O 4 nature (see Supporting Information, Fig. S1). It is estimated from the transmission electron microscopy (TEM) images that ca. 80% of the products are nanoboxes and the remainder is irregularly aggregated Co 3 O 4 particles. The walls of the nanoboxes are composed of small nanocrystals, and the length of the nanobo...

A liquid-phase redox process has been designed to prepare monodispersed Co 3 O 4 nanocrystals with particle sizes of 2 nm (spherical), 2.5 nm (cubelike), and 4.7 nm (cubelike). The nanocrystals were characterized by transmission electron microscopy (TEM), high-resolution TEM, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric techniques. The nucleation and growth, which were tracked by UV-visible spectroscopy, can be separated by adjusting the solubility of sodium nitrate, and the smallest possible Co 3 O 4 nanocubes, 2.5 nm on a side, were obtained. A solubility-controlled mechanism for the redox reaction is discussed which is critical in avoiding secondary nucleation and interparticle ripening growth of Co 3 O 4 nanocrystals.

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Rhizoctonia solani, one of the most detrimental necrotrophic pathogens, causes rice sheath blight and poses a severe threat to production. Focus on the function of effectors secreted by necrotrophic pathogens during infection has grown rapidly in recent years. However, little is known about the virulence and mechanisms of these proteins. In this study, we performed functional studies on putative effectors in R. solani and revealed that AGLIP1 out of 13 putative effectors induced cell death in Nicotiana benthamiana. AGLIP1 was also demonstrated to trigger cell death in rice protoplasts. The predicted lipase active sites and signal peptide (SP) of this protein were required for the cell death-inducing ability. AGLIP1 was greatly induced during R. solani infection in rice sheath. The AGLIP1’s virulence function was further demonstrated by transgenic technology. The pathogenesis-related genes induced by pathogen-associated molecular pattern and bacteria were remarkably inhibited in AGLIP1-expressing transgenic Arabidopsis lines. Ectopic expression of AGLIP1 strongly facilitated disease progression in Arabidopsis caused by the type III secretion system-defective mutant from Pseudomonas syringae pv. tomato DC3000. Collectively, these results indicate that AGLIP1 is a possible effector that plays a significant role in pathogen virulence through inhibiting basal defenses and promoting disease development in plants.

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