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Three new titanium oxo-clusters Ti4O2(OiPr)10(OOCPhMe)2 (I), Ti6O4(OEt)8(OOCPhMe)8 (II) and Ti6O6(OEt)6(OOCCHPh2)6 (III) were obtained by easy one-step solvothermal reactions of titanium(iv) isopropoxide, alcohols and carboxylic acids. The three compounds were characterized by single-crystal and powder X-ray diffraction, TGA/DSC, optical and electron microscopy, and FTIR and NMR spectroscopy. X-ray powder diffraction and spectroscopy confirmed the purity of the compounds. Structural analysis indicates that in all compounds the titanium(iv) ions are six-coordinated (distorted octahedra). (I) is a tetranuclear complex containing a Ti44-O)(μ2-O) core, which is linked by two (μ2-OOCPhMe), four (μ2-OiPr) and six OiPr ligands. (II) and (III) are hexanuclear complexes with different cores, respectively Ti63-O)22-O)2 and Ti63-O)6. The coordination sphere of the Ti atoms is filled by eight (μ2-OOCPhMe), two (μ2-OEt) and six OEt in (II) and six (μ2-OOCHPh2) and six OEt in (III). Different steric hindrance of substituents attached to the carboxyl group or different concentrations lead to three main different cluster geometries with two ligands. The tetranuclear and the hexanuclear clusters were obtained with the OOCPhMe ligand, while the hexagonal prism cluster was obtained with the OOCCHPh2 ligand. Hirshfeld surface calculations indicated that the packing is driven by C–O⋯H–C weak hydrogen bonds. The clusters can be used as molecular models of organic molecules bonded to titania surface, used in organic photovoltaic (dye sensitized solar cells) or other optoelectronic applications.

Crystal structures of three novel titanium oxo-clusters with different cores and ligands obtained by an easy and convenient solvothermal method.  相似文献   
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Laser therapies have been shown to provide symptom improvement in patients with erythema and telangiectasia of rosacea; however, they are associated with side effects such as erythema. Combinatorial treatment with pharmacological agents and laser have demonstrated better efficacy, fewer side effects and continued long-term remission compared with monotherapies. A case of moderate facial erythema that responded well to combination treatment with brimonidine 3 mg/g gel and a treatment course of potassium-titanyl phosphate (KTP) laser therapy is presented, showing a reduction from baseline, maintained after final laser session, by applying brimonidine 3 mg/g gel daily. Using brimonidine 3 mg/g gel to target post-laser treatment erythema is highly effective in minimising refractory erythema. Continued use of brimonidine 3 mg/g gel provides a sustained reduction of erythema, increasing the visibility of other signs and symptoms of rosacea that may be present. This can facilitate the treatment of these additional signs and symptoms.  相似文献   
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Hair shedding in female patients is a frequent complaint in dermatological, endocrinological, and gynecological consults. Previously, the Sinclair Hair Shedding Scale was developed to assess normal versus excessive hair shedding in female pattern hair loss (FPHL) subjects. However, the prevalence of hair shedding in females not suffering from FPHL is unknown. To gain better understanding of hair shedding in the general population, we recruited 300 subjects visiting a public hospital for conditions other than alopecia. Of the 300 subjects recruited, 263 did not suffer from FPHL. Among those subjects, approximately 40% reported experiencing excessive hair shedding (as defined by the Sinclair Hair Shedding Scale) on hair washing days. In comparison, in our subject population, approximately 60% of subjects with FPHL reported excessive hair shedding on hair washing days. To best of our knowledge, this is the first study to quantify the prevalence of hair shedding in women. While, no treatment currently exists for this condition, we hope that this study would encourage physicians and researchers to address this frequent concern.  相似文献   
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