FORMULATION AND PHYSICOCHEMICAL STABILITY OF 20% GLYCOLIC ACID CREAMS USING POLYACRYLAMIDE, C13-14 ISOPARAFFIN, LAURETH-7 AND COMBINATION OF POLYACRYLAMIDE, C13-14 ISOPARAFFIN, LAURETH 7 WITH A GLUKOLIPID OF VEGETABLE ORIGIN

Glycolic acid is a α-hydroxy acids (AHAs). It are used in skin lightening creams. It were developed formulation of 20% glycolic acid creams. The creams were made using 4% of polyacrylamide, C13-14 isoparaffin, laureth-7 as a thickening agent for cream gels and emulsions base and combination of 1.5% of polyacrylamide, C13-14 isoparaffin, laureth-7 and 5% of a glukolipid of vegetable origin as emulisufier agent. Then the physicochemical stabilities were tested using climatic chamber for 30 days at 40˚C with 75% Relative Humidity (RH). The parameters stability observed were organoleptic, droplet size, density, viscosity, emulsion type, phase separation, pH and concentration of acid glikolat.Organoleptis, droplet size, density, viscosity, type of emulsion and phase separation of all of creams were stable, but the pH decreased during the storage time. The time of the concentration of glycolic acid remaining to 90% in cream using using 4% of polyacrylamide, C13-14 isoparaffin, laureth-7 and using combination of using 4% of polyacrylamide, C13-14 isoparaffin, laureth-7 with 5% of a glukolipid of vegetable origin were 30 and 32 days respectively

Cascade metathesis reactions for the synthesis of taxane and isotaxane derivatives

Tricyclic isotaxane and taxane derivatives and have been synthesized by a very efficient cascade ring-closing dienyne metathesis (RCDEYM) reaction, which formed the A and B rings in one operation. When the alkyne is present at C13 (with no neighboring gem-dimethyl group), the RCEDYM reaction leads to 14,15-isotaxanes 16a,b and 18b with the gem-dimethyl group on the A ring. If the alkyne is at the C11 position (and thus flanked by a gem-dimethyl group), RCEDYM reaction only proceeds in the presence of a trisubstituted olefin at C13, which disfavors the competing diene ring-closing metathesis reaction, to give the tricyclic core of Taxol 44

Heavy-flavor azimuthal correlations of D mesons

Observables of heavy-quark azimuthal correlations in heavy-ion collisions are a new and promising tool for the investigation of the in-medium energy loss. We explore the potential of these observables to discriminate the collisional and radiative contributions within a hybrid EPOS+MC@sHQ transport approach.Comment: final version of proceedings for SQM 2013, C13-07-22.

c13-Sixth after Epiphany

Sixth after Epiphan

High Resolution X-Ray Imaging of the Center of IC342

We presented the result of a high resolution (FWHM~0.5'') 12 ks Chandra HRC-I observation of the starburst galaxy IC342 taken on 2 April 2006. We identified 23 X-ray sources within the central 30' x 30' region of IC342. Our HRC-I observation resolved the historical Ultraluminous X-ray sources (ULX), X3, near the nucleus into 2 sources, namely C12 and C13, for the first time. The brighter source C12, with L(0.08-10keV)=(6.66\pm0.45)\times10^{38}ergs^-1, was spatially extended (~82 pc x 127 pc). From the astrometric registration of the X-ray image, C12 was at R.A.=03h:46m:48.43s, decl.=+68d05m47.45s, and was closer to the nucleus than C13. Thus we concluded that source was not an ULX and must instead be associated with the nucleus. The fainter source C13, with L(0.08-10keV)=(5.1\pm1.4) x 10^{37}ergs^-1 was consistent with a point source and located $6.51'' at P.A. 240 degree of C12. We also analyzed astrometrically corrected optical Hubble Space Telescope and radio Very Large Array images, a comparison with the X-ray image showed similarities in their morphologies. Regions of star formation within the central region of IC342 were clearly visible in HST H alpha image and this was the region where 3 optical star clusters and correspondingly our detected X-ray source C12 were observed. We found that a predicted X-ray emission from starburst was very close to the observed X-ray luminosity of C12, suggesting that nuclear X-ray emission in IC342 was dominated by starburst. Furthermore, we discussed the possibility of AGN in the nucleus of IC342. Although our data was not enough to give a firm existence of an AGN, it could not be discarded.Comment: 29 page, 8 figures, accepted by Ap

Study of cascade ring-closing metathesis reactions en route to an advanced intermediate of Taxol

A highly functionalized intermediate in the synthesis of Taxol has been synthesized, which features the tricyclic core and the required oxygen substituents at C1, C2, C7, C10 and C13. The key step, a ring-closing dienyne metathesis (RCDEYM) reaction, has been thoroughly optimized to favor the tricyclic product over the undesired bicyclic product resulting from diene metathesis