Chemical Changes in the Broccoli Volatilome Depending on the Tissue Treatment

The storage of plant samples as well as sample preparation for extraction have a significant impact on the profile of metabolites, however, these factors are often overlooked during experiments on vegetables or fruit. It was hypothesized that parameters such as sample storage (freezing) and sample pre-treatment methods, including the comminution technique or applied enzyme inhibition methods, could significantly influence the extracted volatile metabolome. Significant changes were observed in the volatile profile of broccoli florets frozen in liquid nitrogen at −20 °C. Those differences were mostly related to the concentration of nitriles and aldehydes. Confocal microscopy indicated some tissue deterioration in the case of slow freezing (−20 °C), whereas the structure of tissue, frozen in liquid nitrogen, was practically intact. Myrosinase activity assay proved that the enzyme remains active after freezing. No pH deviation was noted after sample storage - this parameter did not influence the activity of enzymes. Tissue fragmentation and enzyme-inhibition techniques applied prior to the extraction influenced both the qualitative and quantitative composition of the volatile metabolome of broccoli.     

Assessing the In Vitro Activity of Selected Porphyrins in Human Colorectal Cancer Cells

Standard in vitro analyses determining the activity of different compounds included in the chemotherapy of colon cancer are currently insufficient. New ideas, such as photodynamic therapy (PDT), may bring tangible benefits. The aim of this study was to show that the biological activity of selected free-base and manganese (III) metallated porphyrins differs in the limitation of colon cancer cell growth in vitro. White light irradiation was also hypothesized to initiate a photodynamic effect on tested porphyrins. Manganese porphyrin (>1 μM) significantly decreased the viability of the colon tumor and normal colon epithelial cells, both in light/lack of light conditions, while decreasing a free-base porphyrin after only 3 min of white light irradiation. Both porphyrins interacted with cytostatics in an antagonistic manner. The manganese porphyrin mainly induced apoptosis and necrosis in the tumor, and apoptosis in the normal cells, regardless of light exposure conditions. The free-base porphyrin conducted mainly apoptosis and autophagy. Normal and tumor cells released low levels of IL-1β and IL-10. Tumor cells released a low level of IL-6. Light conditions and porphyrins were influenced at the cytokine level. Tested manganese (III) metallated and free-base porphyrins differ in their activity against human colon cancer cells. The first showed no photodynamic, but a toxic activity, whereas the second expressed high photodynamic action. White light use may induce a photodynamic effect associated with porphyrins.     

Investigation of the transport processes in tetramethoxysilane gel by the moiré fringes method

Moiré fringes method have been used in order to study the mass transport processes in tetramethoxysilane (TMS) gel in respect of crystal growth experiments. Diffusion coefficients of potassium dihydrogen phosphate (KDP) solution and ethanol in pure and soaked TMS gel have been measured.     

Contractible affine surfaces with quotient singularities

We consider contractible affine surfaces of negative Kodaira dimension with only quotient singularities. We prove that the smooth locus of such a surface has negative Kodaira dimension. It follows that if such a surface has only one singular point, then it is isomorphic to a quotient C²/G, where G is a finite group acting linearly on C².     

Phantom Friedmann cosmologies and higher-order characteristics of expansion

We discuss a more general class of phantom (p < −?) cosmologies with various forms of both phantom (w < −1), and standard (w > −1) matter. We show that many types of evolution which include both Big-Bang and Big-Rip singularities are admitted and give explicit examples. Among some interesting models, there exist non-singular oscillating (or “bounce”) cosmologies, which appear due to a competition between positive and negative pressure of variety of matter content. From the point of view of the current observations the most interesting cosmologies are the ones which start with a Big-Bang and terminate at a Big-Rip. A related consequence of having a possibility of two types of singularities is that there exists an unstable static universe approached by the two asymptotic models—one of them reaches Big-Bang, and another reaches Big-Rip. We also give explicit relations between density parameters Ω and the dynamical characteristics for these generalized phantom models, including higher-order observational characteristics such as jerk and “kerk.” Finally, we discuss the observational quantities such as luminosity distance, angular diameter, and source counts, both in series expansion and explicitly, for phantom models. Our series expansion formulas for the luminosity distance and the apparent magnitude go as far as to the fourth-order in redshift z term, which includes explicitly not only the jerk, but also the “kerk” (or “snap”) which may serve as an indicator of the curvature of the universe.     

Fourier type 2 operators with respect to locally compact abelian groups

A linear and bounded operator T between Banach spaces X and Y has Fourier type 2 with respect to a locally compact abelian group G if there exists a constant c > 0 such that∥T ∥₂ ≤ c∥f∥₂ holds for all X‐valued functions f ∈ L^X₂(G) where is the Fourier transform of f. We show that any Fourier type 2 operator with respect to the classical groups has Fourier type 2 with respect to any locally compact abelian group. This generalizes previous special results for the Cantor group and for closed subgroups of ?ⁿ. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)