The catalytic performances of supported gold nanoparticles depend critically on the nature of support. Here, we report the first evidence of strong metal-support interactions (SMSI) between gold nanoparticles and ZnO nanorods based on results of structural and spectroscopic characterization. The catalyst shows encapsulation of gold nanoparticles by ZnO and the electron transfer between gold and the support. Detailed characterizations of the interaction between Au nanoparticles and ZnO were done with transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), electron paramagnetic resonance (EPR), and FTIR study of adsorbed CO. The significance of the SMSI effect is further investigated by probing the efficiency of CO oxidation over the Au/ZnO-nanorod. In contrast to the classical reductive SMSI in the TiO(2) supported group VIII metals which appears after high temperature reduction in H(2) with electron transfer from the support to metals, the oxidative SMSI in Au/ZnO-nanorod system gives oxygen-induced burial and electron transfer from gold to support. In CO oxidation, we found that the oxidative SMSI state is associated with positively charged gold nanoparticles with strong effect on its catalytic activity before and after encapsulation. The oxidative SMSI can be reversed by hydrogen treatment to induce AuZn alloy formation, de-encapsulation, and electron transfer from support to Au. Our discovery of the SMSI effects in Au/ZnO nanorods gives new understandings of the interaction between gold and support and provides new way to control the interaction between gold and the support as well as catalytic activity.

Keywords:Oxidative cyclization / Tetrahydrofurans / Ruthenium / Oxidation / CatalysisWe report a highly efficient procedure for the oxidative cyclization of 1,5-dienes, which generally allows for high yields and selectivities. A solid-supported terminal oxidant and a finely tuned solvent mixture have both been identified as critical factors for this high efficiency. As little as 0.2 mol-% ruthenium(III) chloride as a pre-catalyst for the ruthenium te-

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Objective: The aim of this study is to evaluate clinical data from a large cohort of acromegalic patients with and without hyperprolactinemia. Design and methods: Between January 2002 and June 2010, a set of data on 279 acromegalic patients undergoing transsphenoidal surgery was available. Based on preoperative GH and prolactin (PRL) levels, patients were divided into GH and GHCPRL groups. A stabilization or a further improvement of postoperative changes in clinical, hormonal, immunohistochemical, and magnetic resonance imaging parameters was observed in all patients throughout the follow-up period. Results: The GH group had significantly more coarse facial features, large hands and feet, hypertension, and diabetes mellitus compared with the GHCPRL group but significantly less menstrual disorders (13.8 vs 54.3%, P!0.001) and galactorrhea (3.1 vs 22.4%, P!0.001). The GH group had a higher age at diagnosis compared with the GHCPRL group (45.6G13.9 vs 40.4G11.4 years, PZ0.001). The GH group had a smaller mean maximal diameter of the adenomas (2.2G0.9 vs 2.6G1.1 cm, PZ0.004). There were no significant correlations between hormone levels and the immunohistochemical results. According to the criteria for hormonal cure of acromegaly, the surgical control rates in the GH and GHCPRL groups were 68.4 and 59.7% respectively (PZ0.187). Tumor size was an important factor that affected the results of the operations. The rates of surgical control in GH and GHCPRL groups were 80.7 and 69.1% respectively (PZ0.037), and the recurrence rates in the two groups were 7.1 and 11.3% respectively (PZ0.185). Conclusions: Compared with patients with merely GH-secreting adenomas, acromegalic patients with hyperprolactinemia are characterized by an earlier onset of disease, lesser acromegalic features, lower GH levels, but larger tumor sizes, whereas in female patients, GH-PRL secreting adenomas are associated with higher incidences of menstrual disorders and galactorrhea.

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