Single-crystalline Ni nanowires have been successfully fabricated with anodic aluminum oxide as template by electrodeposition. Structural characterization (X-ray diffraction, XRD, and high-resolution transmission electron microscopy, HRTEM) shows that the single-crystalline Ni nanowire has a preferred orientation along the [220] direction. The effects of electrochemical deposition conditions on the structure of Ni nanowires are systematically studied to investigate the growth mechanism. Possible reasons for the growth of the single-crystalline Ni nanowires were discussed on the basis of electrochemistry and thermodynamics. These single-crystalline Ni nanowires have exhibited excellent magnetic properties (large anisotropy, large coercivity, and high remanence). By a similar process, single-crystalline Co nanowires with hexagonal close-packed (hcp) structure were achieved, also having large anisotropy, large coercivity (1.8 kOe), and high remanence ratio (80.8%).

SummaryTrypanosoma brucei, a flagellated protozoan parasite causing human sleeping sickness, relies on a subpellicular microtubule array for maintenance of cell morphology. The flagellum is attached to the cell body through a poorly understood flagellum attachment zone (FAZ), and regulates cell morphogenesis using an unknown mechanism. Here we identified a new FAZ component, CC2D, which contains coiled-coil motifs followed by a C-terminal C2 domain. T. brucei CC2D is present on the FAZ filament, FAZ-juxtaposed ER membrane and the basal bodies. Depletion of CC2D inhibits the assembly of a new FAZ filament, forming a FAZ stub with a relatively fixed size at the base of a detached, but otherwise normal, flagellum. Inhibition of new FAZ formation perturbs subpellicular microtubule organization and generates short daughter cells. The cell length shows a strong linear correlation with FAZ length, in both control cells and in cells with inhibited FAZ assembly. Together, our data support a direct function of FAZ assembly in determining new daughter cell length by regulating subpellicular microtubule synthesis.

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A Golgi-associated bi-lobed structure was previously found to be important for Golgi duplication and cell division in Trypanosoma brucei. To further understand its functions, comparative proteomics was performed on extracted flagellar complexes (including the flagellum and flagellum-associated structures such as the basal bodies and the bi-lobe) and purified flagella to identify new bi-lobe proteins. A leucine-rich repeats containing protein, TbLRRP1, was characterized as a new bi-lobe component. The anterior part of the TbLRRP1-labeled bi-lobe is adjacent to the single Golgi apparatus, and the posterior side is tightly associated with the flagellar pocket collar marked by TbBILBO1. Inducible depletion of TbLRRP1 by RNA interference inhibited duplication of the bi-lobe as well as the adjacent Golgi apparatus and flagellar pocket collar. Formation of a new flagellum attachment zone and subsequent cell division were also inhibited, suggesting a central role of bi-lobe in Golgi, flagellar pocket collar and flagellum attachment zone biogenesis.

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In this paper, we report a facile synthetic approach for preparing water-soluble Fe 3 O 4 nanoparticles with a surface-surrounded layer by the use of polyethylene glycol(5) nonylphenyl ether (NP5) and cyclodextrin (CD) in aqueous medium and also for building nanostructured spherical aggregates from individual magnetic nanoparticles, which were dependent on the concentration of CD and NP5, respectively. The morphology of Fe 3 O 4 nanoparticles was studied by transmission electron microscopy. The mesoporous, spherical aggregates of Fe 3 O 4 particles possessed a BET surface area of ca. 141.1 m 2 g -1 without compromising that of the separated Fe 3 O 4 nanoparticles with coating (164.6 m 2 g -1 ) and still possessed magnetic properties. This method is very meaningful because it directly produces water-soluble magnetic nanoparticles, which is very important for applications of magnetic nanoparticles in biomedical fields and nanostructured spherical aggregates as magnetic carriers.

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Co-ferrite films were prepared using pulsed laser deposition at low substrate temperatures in this work. Magnetic properties of these films have been investigated in the function of substrate temperature and film thickness. A perpendicular coercivity as high as 12.5kOe has been achieved in the Co-ferrite film with a thickness of 33nm deposited at 550°C. The high coercivity mechanism is possibly associated with nanocrystalline structure, textured structure, and presence of relatively large residual strain.