Methylation of DNA by incubation with methylamine and nitrite

DNA was incubated in septum-closed reaction vials with [14C]methylamine and nitrite. The DNA was purified, hydrolysed with hydrochloric acid, and the purines were analysed by h.p.I.c. 7-Methylguanine was detectable as a result of DNA methylation in experiments performed in 100 mM acetate at pH 4. Using different concentrations of amine and nitrite a first order reaction for total amine and a second order for total nitrite could be shown. A study on the pH dependence using 100 mM malonate buffer, pH 2.0-6.0, revealed a maximum rate at pH 3.5, with steep slopes above and below this pH value, in agreement with a mathematical analysis of the reaction equations. The data show that the alkylating agent formed spontaneously by nitrosation and deamination of a primary amine has a long enough lifetime to react with DNA in vitro. Using the reaction orders established here, an extrapolation to lower concentrations found in the stomach can now be performed. Future in vivo experiments on the methylation of gastro-intestinal DNA then would show to what extent DNA in a cell is protected from alkylatio

Towards a sustainable and green extraction of curcuminoids using the essential oil of Cinnamomum cassia

A natural and sustainable alternative to conventional solvents in terms of solubilization and extraction of curcuminoids from Curcuma longa L. was investigated. By mixing ethanol with natural aromas, a drastic increase (up to 30-fold) of curcumin solubility with regard to pure ethanol could be achieved. Through a solubility screening of ten naturally abundant aromas with different functionalities, conducted via UV/vis analysis, cinnamaldehyde was determined to be the most promising one. COSMO-RS calculations combined with 1H and NOESY NMR were conducted to determine the solving mechanism. As a natural source, rich in cinnamaldehyde, essential cinnamon oils were examined concerning their curcumin solving ability with regard to their chemical composition. The best oil, coming from Cinnamomum cassia with a cinnamaldehyde content of 79%, was used successively as a natural solvent for cycle extraction experiments. By encountering a premature saturation, a theoretical model for cycle extractions was proposed

Yellow laser performance of Dy3+^{3+} in co-doped Dy,Tb:LiLuF4_4

We present laser results obtained from a Dy$^{3+}$-Tb$^{3+}$ co-doped LiLuF$_{4}$ crystal, pumped by a blue emitting InGaN laser diode, aiming for the generation of a compact 578 nm source. We exploit the yellow Dy$^{3+}$ transition $^{4}$F$_{9/2}$ $\Longrightarrow$ $^{6}$H$_{13/2}$ to generate yellow laser emission. The lifetime of the lower laser level is quenched via energy transfer to co-doped Tb$^{3+}$ ions in the fluoride crystal. We report the growth technique, spectroscopic study and room temperature continuous wave (cw) laser results in a hemispherical cavity at 574 nm and with a highly reflective output coupler at 578 nm. A yellow laser at 578 nm is very relevant for metrological applications, in particular for pumping of the forbidden $^{1}$S$_{0} \Longrightarrow ^{3}$P$_{0}$ Ytterbium clock transition, which is recommended as a secondary representation of the second in the international system (SI) of units. This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OL.39.006628. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.Comment: 8 pages, 5 figure

Acanalonia conica (Say, 1830) and three other true hopper species new for Austria (Hemiptera: Auchenorrhyncha)

Acanalonia conica (Say, 1830) und drei weitere Zikadenarten neu für Österreich (Hemiptera: Auchenorrhyncha). – Drei Neozoen, Acanalonia conica (Say, 1830), Aplos simplex (Germar, 1830) und Hishimonus hamatus Kuoh, 1976 wurden in einer Gärtnerei in Graz erstmals für Österreich nachgewiesen. Sie wurden wahrscheinlich mit Ziersträuchern aus Italien importiert. Ein weiterer Erstnachweis betrifft Chiasmus conspurcatus (Perris, 1857). Diese Art ist heimisch und wurde an zwei Salzlacken des Nationalparks Neusiedlersee-Seewinkel nachgewiesen. Eine Gesamtliste jener 71 Zikadenarten, die an den beiden Lacken gefunden wurden, wird ebenfalls vorgelegt.  Acanalonia conica (Say, 1830), Aplos simplex (Germar, 1830) and Hishimonus hamatus Kuoh, 1976 are three alien species reported for the first time from Austria. They were found in a garden centre in Graz and presumably imported with ornamental shrubs from Italy. Another first record is Chiasmus conspurcatus (Perris, 1857), an indigenous species found in the Neusiedlersee-Seewinkel National Park. In addition, we present a list of 71 Auchenorrhyncha species found at the two inland salt marshes, where C. conspurcatus occurs

Morphology of three-body quantum states from machine learning

The relative motion of three impenetrable particles on a ring, in our case two identical fermions and one impurity, is isomorphic to a triangular quantum billiard. Depending on the ratio κ of the impurity and fermion masses, the billiards can be integrable or non-integrable (also referred to in the main text as chaotic). To set the stage, we first investigate the energy level distributions of the billiards as a function of 1/κ ∈ [0, 1] and find no evidence of integrable cases beyond the limiting values 1/κ = 1 and 1/κ = 0. Then, we use machine learning tools to analyze properties of probability distributions of individual quantum states. We find that convolutional neural networks can correctly classify integrable and non-integrable states. The decisive features of the wave functions are the normalization and a large number of zero elements, corresponding to the existence of a nodal line. The network achieves typical accuracies of 97%, suggesting that machine learning tools can be used to analyze and classify the morphology of probability densities obtained in theory or experiment