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Nine species of the Brazilian endemic genus, Trembleya, were collected during a floristic survey of the tribe Microlicieae on Serra do Cabral, an isolated mountain range in north-central Minas Gerais State, Brazil. Four of these are newly described and illustrated here: Trembleya inversa, T. purpurascens, T. rubra, and T. serrulata, represent new taxa for the genus. These new species appear to be endemic to Serra do Cabral where they occur in campo rupestre and cerrado vegetation. Serra do Cabral has the distinction of harboring more species of Trembleya than any other mountain range in Brazil. [ABSTRACT FROM AUTHOR]

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The bifunctional transformation of n-hexane was carried out over Pt/MCM-22 based catalysts. MCM-22 was synthesized and submitted to ion exchange with rare earth nitrate solutions of La, Nd and Yb, followed by Pt introduction. Three different methods were used to introduce about 1 wt% of Pt in the zeolite: ion exchange, incipient wetness impregnation and mechanical mixture with Pt/AlO. The bifunctional catalysts were characterized by transmission electron microscopy and by the model reaction of toluene hydrogenation. These experiments showed that, in the ion exchanged sample, Pt is located both within the inner micropores and on the outer surface, whereas in the impregnated one, the metal is essentially located on the outer surface under the form of large particles. The presence of RE elements increases the hydrogenating activity of Pt/MCM-22 since the location of these species at the vicinity of metal particles causes modification on its electronic properties. Whatever the mode of Pt introduction, a fast initial decrease in conversion is observed for n-hexane transformation, followed by a plateau related to the occurrence of the catalytic transformations at the hemicages located at the outer surface of the crystals. The effect of rare earth elements on the hydrogenating function leads to a lower selectivity in dibranched isomers and increased amounts of light products. [ABSTRACT FROM AUTHOR]

The present work deals with preliminary studies concerning a new synthesis approach to prepare SAPO materials with AEL structure and evaluate their catalytic behavior in the hydroisomerization of long paraffins. The new SAPO-11 catalysts were synthesized with the help of a small amine (methylamine, MA) added during the preparation of the initial gel. As MA incorporates into the structure of the final materials, it contributes, together with DPA (dipropylamine), to an increase in Si incorporation as isolated species, which results in Brønsted acid sites. Thus, this new and original synthesis strategy allows to obtain materials with enhanced Brønsted acidity when compared with free MA materials. The catalysts were tested in n-decane hydroisomerization ( n-decane was used as a model molecule) and confirmed the effect of MA on the acidic properties of the catalysts. The samples synthesized with MA present a higher number of acid sites that increase the catalytic conversion but have a negative effect in the isomerization selectivity, i.e. a more significant amount of cracking products is formed. [ABSTRACT FROM AUTHOR]

Unlabelled: The purpose of this study is to evaluate the efficacy of tattoo removal using topical imiquimod 5% cream in conjunction with the 1,064-nm Nd:YAG laser. This procedure for tattoo removal will be compared to laser treatment alone, which is the standard for cosmetic removal of tattoos. Previous studies have linked partial tattoo removal to imiquimod application in a guinea pig model.Methods: This was a small-sized, double-blinded, placebo-controlled trial with patients with Fitzpatrick skin types I-IV (light skin) who were 18-65 years of age. The patients were required to have had two tattoos of similar age and dark blue or black in color in areas that can be covered by clothing. There were four visits in total, with laser treatment and photography being performed on the first visit. Laser settings were with 1,064-nm Nd:YAG with a 10-ns pulse, 3-mm spot size, and 4 J of energy, a standard laser used for tattoo removal. During the second visit, tattoos were randomized and chosen to receive either the laser-imiquimod treatment course or laser-vehicle cream treatment. The patients returned 1 month after the completion of cream application (week #10) and 2 months after the completion of treatment with cream (week #14) for final evaluation and photographing.Results: Three patients were enrolled in this study. All of them are Fitzpatrick skin type IV. All of the patients were compliant with the drug application and have good tolerability with only mild pruritus without changing of vascularity or pigmentation. None of the patients had ulceration or scar development during the cream application.Conclusions: imiquimod plus laser therapy demonstrated a more favorable outcome when evaluated by the investigators or subjects. The mean scores for tattoo clearance from baseline to 2 months after completion of treatment with 5% imiquimod cream versus placebo cream were 4.3 versus 2.7 as rated by investigators and 4.7 versus 2.3 as rated by subjects. No textural changes were observed after therapy and were not shown to be different between the two groups. Further large-scale studies are important in developing a role for the use of imiqumod in laser-assisted tattoo removal. [ABSTRACT FROM AUTHOR]

Copyright of Kew Bulletin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A new and probably endemic species of Cambessedesia DC. is described from campo rupestre vegetation, as part of a floristic survey of Melastomataceae from the São José mountain range, Tiradentes District, Minas Gerais State, Brazil. [ABSTRACT FROM AUTHOR]

Symplocos saxatilis from Serra do Cipó, Minas Gerais State, Brazil, is newly described and illustrated on the basis of field and herbarium studies. It appears to be restricted to “campo rupestre” (rocky field) habitats. This new species is characterized by its 1- to 3-flowered pedunculate inflorescence, 11 to 14 staminodes of the pistillate flowers, and 0.7–1.5 mm thick endocarp. [ABSTRACT FROM AUTHOR]

PtAl/MCM-41 and PtAl/SBA-15 materials were prepared by post-synthesis alumination followed by introduction of platinum by ion exchange. The samples were characterized by pyridine adsorption followed by FTIR and TPR of hydrogen. The catalytic behavior was explored in the transformation of n-hexane. [ABSTRACT FROM AUTHOR]