A new class of exact hairy black hole solutions

We present a new class of black hole solutions with a minimally coupled scalar field in the presence of a negative cosmological constant. We consider an one-parameter family of self-interaction potentials parametrized by a dimensionless parameter g. When g = 0, we recover the conformally invariant solution of the Martinez–Troncoso–Zanelli (MTZ) black hole. A non-vanishing g signals the departure from conformal invariance. Thermodynamically, there is a critical temperature at vanishing black hole mass, where a higher-order phase transition occurs, as in the case of the MTZ black hole. Additionally, we obtain a branch of hairy solutions which undergo a first-order phase transition at a second critical temperature which depends on g and it is higher than the MTZ critical temperature. As g → 0, this second critical temperature diverges.     

Oscillatory behavior of Rh/YSZ under electropromoted conditions

Electrochemical induced oscillations were studied during ethylene oxidation over Rh films deposited on YSZ. Oscillations period and amplitude were for the first time analyzed depending on the applied potential or current, related with cyclic oxidation and reduction reactions and discussed on the basis of the phenomenon of the electrochemical promotion of catalysis.     

Synthesis of methyl substituted [5,6]- and [7,8]-fused pyridocoumarins via the iodine-catalyzed reaction of aminocoumarins with n-butyl vinyl ether

2-Methyl substituted [5,6]- or [7,8]-fused pyridocoumarins are prepared from the Povarov-type, three-component reactions of 6- or 7-aminocoumarins with n-butyl vinyl ether, catalyzed by iodine in refluxing acetonitrile, through the aza-Diels–Alder reaction of the initially formed N-iminoaminocoumarins with a second equivalent of the vinyl ether.     

Characterization of the human serum depletome by label-free shotgun proteomics

While it is known that immunoaffinity depletion of abundant proteins in serum removes additional proteins beyond those targeted, there has been little characterization of the co-depleted proteins in the high abundant fraction, which we refer to here as the "depletome". We present evidence of co-depletion of non-targeted proteins in human serum using a top-20 immunodepletion column, as shown by label-free liquid chromatography mass spectrometry (LC-MS(E)) profiling. This led to identification of 147 proteins which were specific for this fraction and comprised proteins with functions predominantly in binding and transport of nucleotides, metal ions, carbohydrates and lipids. These results suggest that further studies on this commonly ignored serum fraction may provide new insights into clinical proteomics.     

Hydrogen-bonded liquid crystals derived from supramolecular complexes of pyridylated poly(propyleneimine) dendrimers and a cholesterol-based carboxylic acid

Diaminobutane poly(propyleneimine) dendrimers of second to fifth generations were functionalized by the introduction of pyridyl moieties at their primary amino groups through their interaction with 3-pyridyl isothiocyanate. These pyridylated diaminobutane poly (propyleneimine) dendrimers were subsequently mixed with 3-cholesteryloxycarbonylpropanoic acid to form the corresponding hydrogen-bonded supramolecular complexes. The materials obtained exhibit smectic A phases over a relatively broad temperature range from about 60°C to 140°C. Within the smectic layer the cholesteryl moieties are almost orthogonal above and below to the dendrimeric portion of the molecule. On cooling, the materials form liquid crystalline glasses which retain the structural characteristics of the smectic A phase.     

Intercalation Study of Low‐Molecular‐Weight Hyperbranched Polyethyleneimine into Graphite Oxide

We report for the first time the intercalation of low‐molecular‐weight hyperbranched polyethyleneimine (PEI) into graphite oxide (GO) for the facile, bulk synthesis of novel graphene‐based hybrid (GO‐PEI) materials exhibiting tailored interlayer galleries. The size of the intercalant as well as the loading in GO were systematically investigated to determine their contribution to the basal spacing of the resulting materials. Powder X‐ray diffraction measurements demonstrated the generation of constrained hybrid systems along the c axis that exhibit considerably increased interlayer distances compared with the starting, pristine GO. The results of X‐ray photoelectron and FTIR studies are consistent with a “grafting‐to” process of the intercalated PEI with the oxygen functional groups present along the GO framework. Furthermore, it was found that a great number of the nitrogen‐containing groups in PEI still remain available within the newly formed, confined micro‐environment of intercalated GO galleries. The increased surface area of the GO‐PEI hybrids in conjunction with the remaining available active groups of intercalated PEI render the synthesised hybrids very attractive candidates as nanostructured adsorbents.     

Using ICP-qMS to trace the uptake of nanoscale titanium dioxide by microalgae–potential disadvantages of vegetable reference material

As nanoscale materials have gained in economic importance over recent years, concerns about accumulation in the environment and, consequently, analysis of nanoparticles in biological material have increasingly become the focus of scientific research. A nanomaterial used in a wide range of food, consumer and household products is titanium dioxide (nTiO₂). Monitoring of nTiO₂ via determination of elemental titanium (Ti) can be very challenging because of a variety of possible interferences. This work describes problems during the development of a quantification method for titanium dioxide (TiO₂) using inductively coupled plasma-quadrupole mass spectrometry (ICP-qMS). To evaluate the analytical method, certified vegetable reference material NCS DC 73349 was used. Interestingly, measurements of NCS DC 73349 seemed to result in acceptable recovery values—however, this was without considering interferences or conceivable differences in the natural isotopic abundance of the certified titanium calibration solution and NCS DC 73349. Actually, recoveries were lower than initially assumed. The potential interferences causing augmented recovery could be attributed to the presence of the elements sulfur (S) and phosphorus (P), which were able to form oxide ions and nitrogen-interfering species. The effect of such interfering cluster ions could be prevented by dry ashing as a sample preparation step, to evaporate S and P, before digestion with aqua regia in a high-pressure asher (HPA). Final practicability of the analysis method was proved by monitoring the uptake of nTiO₂ by the microalgae Scenedesmus acutus in an environmental exposure study.

Synthesis Through Three‐Component Reactions Catalyzed by FeCl3 of Fused Pyridocoumarins as Inhibitors of Lipid Peroxidation

2,4‐Diphenyl substituted fused pyridocoumarins have been synthesized by one‐pot three‐component domino reactions of aminocoumarins, benzaldehyde, and phenylacetylene by using FeCl₃ (10%) as catalyst under reflux or MW irradiation. The new compounds were tested as inhibitors of lipid peroxidation. The 7,9‐diphenyl‐2H‐pyrano[2,3‐g]quinolin‐2‐one presents interesting results and could serve as lead compound.     

Isometric deformations of surfaces preserving the third fundamental form

We study the following problem: To what extend is a surface in the Euclidean space \(\mathbb{R}^{4}\) determined by the third fundamental form? We prove the existence of families of surfaces in \(\mathbb{R}^{4}\) which allow isometric deformations with isometric but not congruent Gaussian images. In particular, we provide a method which gives locally all surfaces in \(\mathbb{ R}^{4}\) with conformal Gauss map that allow such deformations. As a consequence, we have a way for constructing non-spherical pseudoumbilical surfaces in \(\mathbb{R}^{4}.\)     

Curcumin as the OO bidentate ligand in "2 + 1" complexes with the [M(CO)3]+ (M = Re, 99mTc) tricarbonyl core for radiodiagnostic applications

The synthesis and characterization of "2 + 1" complexes of the [M(CO)(3)](+) (M = Re, (99m)Tc) core with the β-diketones acetylacetone (complexes 2, 8) and curcumin (complexes 5, 10 and 6, 11) as bidentate OO ligands, and imidazole or isocyanocyclohexane as monodentate ligands is reported. The complexes were synthesized by reacting the [NEt(4)](2)[Re(CO)(3)Br(3)] precursor with the β-diketone to generate the intermediate aqua complex fac-Re(CO)(3)(OO)(H(2)O) that was isolated and characterized, followed by replacement of the labile water by the monodentate ligand. All complexes were characterized by mass spectrometry, NMR and IR spectroscopies, and elemental analysis. In the case of complex 2, bearing imidazole as the monodentate ligand, X-ray analysis was possible. The chemistry was successfully transferred at (99m)Tc tracer level. The curcumin complexes 5 and 6, as well as their intermediate aqua complex 4, that bear potential for radiopharmaceutical applications due to the wide spectrum of pharmacological activity of curcumin, were successfully tested for selective staining of β-amyloid plaques of Alzheimer's disease. The fact that the complexes maintain the affinity of the mother compound curcumin for β-amyloid plaques prompts for further exploration of their chemistry and biological properties as radioimaging probes.