We have measured the specific heat (C~) of cyclohexane at 120& T &300 K when cyclohexane was physically restricted in porous Spherosil (silica) samples of pore radii 4, 7.5, 15, 30, and 62.5 nm. The behaviors of the monoclinic-to-cubic structural transition and of the melting transition of cyclohexane were determined.As expected, both transition temperatures, i.e. , solid-solid and melting, inversely scaled with the pore radius (R~}. It is argued that the surface heterogeneity, the presence of hydroxyl groups, and the radius of curvature (especially for smaller pores) induce considerable disorder in the adsorbed layers of cyclohexane, thus, resulting in the nucleation of crystalline grains of various sizes rather than in a single crystalline plug of cyclohexane in the porous silica samples. The distribution of the grain boundaries of crystalline cyclohexane produces a specific-heat peak for the melting transition, which almost resembles the A, shape for R~3 0 nm. Unlike the monoclinic-to-cubic transition, the k anomaly of the melting transition does not reflect a logarithmic dependence near the transition temperature. It is also argued, from the comparative observed C~b ehavior of the bulk cyclohexane with the physically restricted cyclohexane, that the cyclohexane liquid is more viscous than the bulk when it is confined in pores of 4 and 7.5 nm.

Disturbing mitotic progression via targeted anti-mitotic therapy is an attractive strategy for cancer treatment. Therefore, the exploration and elucidation of molecular targets and pathways in mitosis are critical for the development of anti-mitotic drugs. Here, we show that cell division cycle 5-like (Cdc5L), a pre-mRNA splicing factor, is a regulator of mitotic progression. Depletion of Cdc5L causes dramatic mitotic arrest, chromosome misalignments and sustained activation of spindle assembly checkpoint, eventually leading to mitotic catastrophe. Moreover, these defects result from severe impairment of kinetochore-microtubule attachment and serious DNA damage. Genome-wide gene expression analysis reveals that Cdc5L modulates the expression of a set of genes involved in the mitosis and the DNA damage response. We further found that the pre-mRNA splicing efficiency of these genes were impaired when Cdc5L was knocked down. Interestingly, Cdc5L is highly expressed in cervical tumors and osteosarcoma. Finally, we demonstrate that downregulation of Cdc5L decreases the cell viability of related tumor cells. These results suggest that Cdc5L is a key regulator of mitotic progression and highlight the potential of Cdc5L as a target for cancer therapy.

Konjac glucomannan (KGM) has attracted extensive attention because of its biodegradable, non-toxic, harmless, and biocompatible features. Its gelation performance is one of its most significant characteristics and enables wide applications of KGM gels in food, chemical, pharmaceutical, materials, and other fields. Herein, different preparation methods of KGM gels and their microstructures were reviewed. In addition, KGM applications have been theoretically modeled for future uses.

ZnO nanotower bundles have been grown on the electrochemically deposited ZnO thin film by a simple hydrothermal process. The influence of surface/interface defects on the structural and optical properties is studied by x-ray diffraction, selected area electron diffraction, and photoluminescence techniques. The formation of ZnO nanotowers and defects may be attributed to kinetic confinement and thermodynamic processes. A wide visible emission band covering nearly the entire visible region is related with the surface/interface defects. By controlling the surface area-to-volume ratio and the width change of the single ZnO nanotower, the emission properties of ZnO nanotowers can be well modified.

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Zinc oxide nanocrystalline films with (002) preferred orientation and intense ultravoilet (UV) emission were prepared by oxidation of zinc-implanted silica at 700°C for 2 h in oxygen ambient. A TEM micrograph showed that ZnO nanocrystalline films with a thickness of about 90 nm were formed on the surface of the Zn-implanted silica substrate. The quality and excitonic properties of the ZnO nanocrystalline films were studied through absorption spectra at room temperature and photoluminescence (PL) spectra in the temperature range from 79 to 300 K. At room temperature, a strong free excitonic emission peak at 377 nm with a very weak deep-level emission can be observed. The intensity ratio of the UV near-band-edge emission to the deep-level emission can reach up to 40. The temperature-dependent PL indicated that the UV near-band-edge emission in the temperature range 79–187 K can be attributed to a free exciton (FE), a bound exciton and the one longitudinal-optical phonon replica of FE lines. The presence of a strong emission of FE lines at 79 K suggested that high-purity ZnO nanocrystalline films have been obtained.

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