Two titanium-oxo-clusters Ti(6)O(4)(o-BDC)(2)(o-BDC(i)Pr)(2)(O(i)Pr)(10) (1) and Ti(6)O(3)(o-BDC)(2)(O(i)Pr)(14) (2) (BDC = benzene dicarboxylate) were prepared by one-step in situ solvothermal synthesis. The compounds are the rare examples of the dicarboxylate-substituted titanium-oxo-clusters. Their crystal structures are successfully measured by single-crystal X-ray analysis. The Ti(6) oxo-clusters of 1 and 2 are constructed by two dual corner-missing cube subunit, Ti(3)O(3). The two subunits are linked by double μ(3)-O bridges for 1 and single μ(2)-O bridge for 2, respectively, and the latter is a new type of carboxylate substituted titanium-oxo-cluster. A photochromic effect was observed upon irradiation of the crystals in the presence of alcohol. The light irradiation changed the color of the crystals from transparent to purple-gray. The Ti(III) signal was detected after the irradiation, and when the sample was exposured in air, superoxide diatomic O(2)(•-) radical was found. Photodegradation of the methyl orange in aqueous dispersions of microcrystals of the cluster 2 was carried out under UV cut white light with the assistance of H(2)O(2).

Much attention has been paid to titanium oxo clusters (TOCs) because of their use as model compounds of bulk nanoscale titanium oxides. On the other hand, doping of TiO 2 with some metal complexes of 1,10-phenanthroline (phen) or bipyridine (bpy) results in low band-gap materials with high photovoltaic conversion efficiency. In this work, two metal-phenanthroline substituted titanium-oxo-clusters, [Ti 17 O 28 (O i Pr) 16 (Co II phen) 2 ] (C1) and [Ti 17 O 28 (O i Pr) 18 (Cd II phen) 2 ] (C2), were successfully prepared by one-step in situ solvothermal synthesis. The structures of the compounds are best described as an oxoisopropanoxo Ti 17 parent fused with two M-phen moieties. They are the first examples of M-phen modified oxo-alkoxy titanium clusters. The band structure of the cluster is modified by the coordination of the metal complex and the absorption of the material is improved. The cluster can not only be used as a model for theoretical study, but can also be used as a precursor to prepare sensitized TiO films.Films (F1) with unique microstructures of hollow spheres, bowls, and doughnuts were obtained by a simple non-template coating method from the solution of Co-phen-TiO cluster C1. The size of the spheres is about 1-2 mm and the thickness of the shell is about 50 nm. Upon repetitive irradiation of the F1 film on the ITO electrode in a three electrode system, a clear photocurrent response was observed.The Co-phen moiety plays an important role in electron transition.

A series of neutral rare earth metal amides with different metal-nitrogen bonds were synthesized and characterized. The selective catalytic activity and reactivity of the complexes incorporating different metal-nitrogen (Ln-N, Ln = rare earth metal) bonds were studied. Treatment of (Me 6), Sm ( 7)) incorporating different Ln-N bonds in good yields. Reaction of 6 or 7 with grease (Me 2 SiO) 3 in toluene produced the selective insertion products [C 6 H 5 N(Me 2 Si)N(C 6 H 5 )(Me 2 SiO)LnN(SiMe 3 ) 2 ] 2 (Ln = Yb (8), Sm ( 9)). The structures of complexes 1, 2, 4, 5, 8, and 9 were additionally determined by single-crystal X-ray analyses. Investigation of catalytic activity of the complexes indicated that the complexes displayed a high selectivity on cyclotrimerization or cyclodimerization toward isocyanates depending on the nature of the isocyanates. These catalysts have the advantages of a high reactivity and good selectivity toward isocyanates, easy preparation, low catalyst loading, and high conversion, as well as mild reaction conditions.

The xeroderma pigmentosum complementation group C (XPC) is responsible for removal of bulky helix-distorting DNA lesions. Several polymorphisms of XPC gene may modulate the colorectal cancer (CRC) susceptibility. We assessed the association of XPC Lys939Gln (A/C), Ala499Val (C/T), and PAT (-/+) polymorphisms with CRC risk in a population-based case-control study which included 421 CRC patients and 845 controls. For Lys939Gln, the CC genotype was associated with a significantly increased risk of CRC (odds ratio (OR)=1.5; 95% confidence interval (CI)=1.0-2.2) compared with the AA genotype. The subjects with PAT +/+ genotype had a significantly increased risk of CRC (OR=1.5; 95% CI=1.0-2.3), compared with those with PAT-/- genotype. Though no significant association between Ala499Val and CRC risk was observed, we found that individuals carrying the CT+TT genotypes showed a significantly decreased risk of rectal cancer (OR=0.7; 95% CI=0.5-1.0). Additionally, the haplotype C+C was associated with a significantly increased CRC risk (OR=1.3; 95% CI=1.0-1.6), compared with the most common haplotype A-T. Further, individuals with four or more risk alleles exhibited a significantly increased risk of CRC (OR=1.4; 95% CI=1.0-2.0), with a significant gene-dosage effect (P for trend=0.038). Besides, never tea drinking was associated with a significantly increased risk of CRC (OR=2.3; 95% CI=1.7-3.3). Our results suggest that the XPC polymorphisms may modulate CRC susceptibility independently or jointly, and tea drinking has a protective effect on CRC.

Attention has been paid to titanium-oxo clusters (TOCs) modified with functional molecules, because they can be considered as model systems for dye-sensitized titanium oxides in terms of their information in structures and electron transfer. We select 9-anthracenecarboxylate (9-AC) as a photoactive ligand and prepare two model compounds, [Ti6O6(O(i)Pr)6(9-AC)6] (1) and [Ti6O4(O(i)Pr)6(cat)4(9-AC)2] (2) (where cat = catecholate). Structures of the TOCs and the dye-TOC linkage are characterized by single-crystal analysis. Solvent-induced fluorescence change is observed for the cluster solution, and the fluorescence can be turned off by irradiating and on by oxygen bubbling. Photoinduced Ti(III) is responsible for the fluorescence extinction. The photocurrent conversion property of the clusters is examined by use of a three-electrode cell with cluster-coated indium tin oxide (ITO) electrodes. The results indicate that 9-AC is an effective photosensitizer and cluster 1 shows higher photocurrent intensity for its multiantenna structure in comparison with that of 2. Density of states for cluster 1 is calculated, in which the discrete energy bands of Ti6O24 include a number of new energy levels for the contribution of 9-AC molecules.

Two benzene dicarboxylate (BDC) and salicylate (SAL) substituted titanium-oxo-clusters, Ti13O10(o-BDC)4(SAL)4(O(i)Pr)16 (1) and Ti13O10(o-BDC)4(SAL-Cl)4(O(i)Pr)16 (2), are prepared by one step in situ solvothermal synthesis. Single crystal analysis shows that the two Ti13 clusters take a paddle arrangement with an S4 symmetry. The non-compact (non-sphere) structure is stabilized by the coordination of BDC and SAL. Film photoelectrodes are prepared by the wet coating process using the solution of the clusters and the photocurrent response properties of the electrodes are studied. It is found that the photocurrent density and photoresponsiveness of the electrodes are related to the number of coating layers and the annealing temperature. Using ligand coordinated titanium-oxo-clusters as the molecular precursors of TiO2 anatase films is found to be effective due to their high solubility, appropriate stability in solution and hence the easy controllability.

The objectives of this cross-sectional study were to estimate non-use of inpatient hospital care service by elderly people in China and to examine associations between service non-use during the past 12 months and an array of predisposing, enabling and need factors. Using a fully structured questionnaire, trained health personnel interviewed 4046 Chinese aged 60 and older in Zhejiang province selected by a two-stage stratified cluster sampling scheme between September and December 2007. Based on the Andersen behavioural model, hierarchical logistic regression analysis was used to explore the predictors of non-use of this service. The rate of non-use was 14.2% [95% confidence interval (CI), 13.1-15.3%] for inpatient hospital care service. Logistic regression analyses revealed that enabling factors were more important than either predisposing or need factors in predicting non-use of inpatient hospital care service.Predisposing factors other than education were not significant, and only the need factor of number of diseases was significant for non-use of inpatient hospital care service. The odds of non-use for those with a college or higher degree were 0.36 times (95% CI, 0.21-0.62) the odds for those with primary or lower education. The odds of non-use in the presence of 4-10 diseases and 1-3 diseases were 3.10 times (95% CI,1.96-4.89) and 2.14 times (95% CI, 1.45-3.14), respectively, of those having no disease. Among the four enabling factors, only degree of living satisfaction score was not significantly associated with non-use of inpatient hospital care service. For elderly persons with higher healthcare expenditure, joining new rural cooperative medical insurance or having low social support, the odds of reporting non-use of inpatient hospital care services were raised by a factor of 1.6-8.0. Findings indicated that, in the absence of universal and comprehensive medical insurance coverage,enabling factors are more important than either predisposing or need factors in predicting non-use.

A series of four coordinate rare earth metal amides with general formula ((CH2SiMe2)[(2,6- IPr2C6H3)N]2)LnN(SiMe3)2(THF) [(Ln = Yb(2), Y (3), Dy (4), Sm (5), Nd (6)] containing a diamido ligand (CH2SiMe2)[(2,6-iPr2C6H3)N]2(2-) with a CH2SiMe2 link were synthesized in good yields via reaction of [(Me3Si)2N]3Ln(III)(mu-Cl)Li(THF)3 with the corresponding diamine (CH2SiMe2)[(2,6-iPr2C6H3)NH]2 (1). All compounds were fully characterized by spectroscopic methods and elemental analyses. The structures of complexes 2, 3, 4, 5, and 6 were determined by single-crystal X-ray analyses. Investigation of the catalytic properties of the complexes indicated that all complexes exhibited a high catalytic activity on the cyclotrimerization of aromatic isocyanates, which represents the first example of cyclopentadienyl-free rare earth metal complexes exhibiting a high catalytic activity and a high selectivity on cyclotrimerization of aromatic isocyanates. The temperatures, solvents, catalyst loading, and the rare earth metal effects on the catalytic activities of the complexes were examined.