A multi-method approach for determination of radionuclide distribution in trinitite

The spatial distribution of radiation within trinitite thin sections have been mapped using alpha track radiography and beta autoradiography in combination with optical microscopy and scanning electron microscopy. Alpha and beta maps have identified areas of higher activity, and these are concentrated predominantly within the surficial glassy component of trinitite. Laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses conducted at high spatial resolution yield weighted average ²³⁵U/²³⁸U and ²⁴⁰Pu/²³⁹Pu ratios of 0.00718 ± 0.00018 (2σ) and 0.0208 ± 0.0012 (2σ), respectively, and also reveal the presence of some fission (¹³⁷Cs) and activation products (^152,154Eu). The LA-ICP-MS results indicate positive correlations between Pu ion signal intensities and abundances of Fe, Ca, U and ¹³⁷Cs. These trends suggest that Pu in trinitite is associated with remnants of certain chemical components from the device and surrounding Trinity test-related structures at ground zero. In contrast, negative correlations between Pu ion signals and SiO₂ and K₂O contents were observed within the glassy matrix of trinitite. This LA-ICP-MS result was corroborated by combined back-scattered electron imaging and alpha radiography, and indicates that Pu was not incorporated into unmelted crystalline grains of precursor minerals (i.e., quartz-SiO₂ and K-feldspar-KAlSi₃O₈) present within the desert sand at the Trinity site. The results from this study indicate that the device-related radionuclides were preferentially incorporated into the glassy matrix in trinitite.     

Antifungal activity of Mongolian medicinal plant extracts

Abstract

The in vitro antifungal activity of extracts obtained from 14 medicinal plants of the mongolian flora were investigated by measuring their minimal inhibitory concentration (MIC) against fungi cause of cutaneous diseases such as Candida species, dermatophytes and Malassezia furfur. Among the species examined, Stellaria dichotoma L., Scutellaria scordifolia L. Aquilegia sibirica Fisch. Et Schrenk. and Hyoscyamus niger L. extracts demonstrated antifungal activity against all studied fungi. In particular, S. scordifolia L. methanol extract, obtained at room temperature, showed the best activity against Candida spp., Malassezia furfur and dermatophytes with GMMIC₅₀ values of 22?µg/mL, 64?µg/mL and 32?µg/mL, respectively. The flavones, luteolin and apigenin, identified in S. scordifolia extracts, and rutin identified in S. dichotoma and Hyoscyamus niger L. extracts, could be responsible of the observed antifungal activity.     

Evaluation of flavonoids and furanocoumarins from Citrus bergamia (Bergamot) juice and identification of new compounds

Bergamot juice (BJ) contains different classes of flavonoids (e.g. flavanones and flavones) that can exert beneficial effects on human health. The aim of this study was to evaluate the qualitative and quantitative composition of a BJ obtained from fruits harvested in Southern Italy (Calabria) at the end of their maturation period. The identity of several flavonoids and furanocoumarins was assessed by co-chromatography, UV spectra and molecular weight comparison. The unknown compounds were dissociated by induced collision (CID-MS) and their identity established through the characteristic ions product. By this approach a complete profile of about twenty compounds (furano-coumarins, flavonoids C- and O-glycosides) present in BJ was obtained. Furthermore, three acylated flavanones, present in amounts of 20.1+/-1.1, 89.3+/-2.2 and 190.1+/-3.1 mg/L, respectively, and which seem to correspond to di-oxalate derivatives of neoeriocitrin, naringin and neohesperidin, were identified for the first time in BJ. The other main flavanones were naringin, neohesperidin and neoeriocitrin, and their content was 167.5+/-1.8, 123.9+/-1.7 and 73.3+/-1.6 mg/L, respectively. Concerning flavones, the total amount in BJ was about 160 mg/L and the main ones were vicenin-2, stellarin-2, rhoifolin and neodiosmin. Bergapten and bergamottin were the primary furanocoumarins in BJ and their amounts were 9.0+/-0.4 and 18.2+/-0.5 mg/L, respectively.     

Accurate quantification of steady and pulsatile flow with segmented k-space magnetic resonance velocimetry

Conventional non-segmented magnetic resonance phase velocity mapping (MRPVM) is an accurate but relatively slow velocimetric technique. Therefore, the aim of this study was to evaluate the accuracy of the much faster segmented k-space MRPVM in quantifying flow. The axial velocity was measured in four straight tubes (inner diameter: 5.6-26.2 mm), using a segmented MRPVM sequence with seven lines of k-space per segment. The flow rate and flow volume were accurately quantified (errors<5%) under steady (r²=0.99) and pulsatile flow (r²=0.98), respectively. The measured velocity profiles and flow rates from the segmented sequence agreed with those from the non-segmented (p>0.05). Changing the slice thickness or the field of view did not affect the accuracy of the measurements. The results of this study suggest that fast, segmented MRPVM can be used for accurate flow quantification.     

Prediction of isocratic nonaqueous reversed-phase high-performance liquid chromatography retention parameters and response factors of triacylglycerols detected by an ultraviolet-diode array-evaporative light-scattering on-line system

Nonaqueous reversed-phase high-performance liquid chromatography of 10 homogeneous triacylglycerol molecular species (TAG), both saturated and unsaturated, is carried out. The eluate from the column is detected by an ultraviolet diode array detector (DAD) on-line with an evaporative light-scattering detector (ELSD). The retention parameters (as selectivities, alpha) for 220 TAGs are determined, and the obtained values are related to the following structural parameters: total carbon number; mono-, di-, and triunsaturated fatty acid residues number/molecule; and monounsaturated fatty acid carbon number. Multiple regression analysis is carried out to obtain a relationship for the prediction of alpha values of any TAG when the same experimental conditions are used. In regard to the quantitative analysis of the separated TAG species, the dependence of response of the two on-line detectors on the aforementioned structural parameters is studied. Three different wavelengths (205, 210, and 215 nm) are considered for TAG detection by DAD; in each case, the obtained multiple regression model shows a good correlation between the dependent variable and predictive values of the TAG species (response factors and considered structural parameters, respectively). The ELSD gives responses exponentially related to injected amounts. Also, in this case, an attempt to relate the response factors of each considered detector to some structural parameters of TAG species is carried out. The results of this study are used to analyze the TAG fraction from an olive oil.     

Clifford Fourier Transformation and Uncertainty Principle for the Clifford Geometric Algebra Cl 3,0

First, the basic concept of the vector derivative in geometric algebra is introduced. Second, beginning with the Fourier transform on a scalar function we generalize to a real Fourier transform on Clifford multivector-valued functions Third, we show a set of important properties of the Clifford Fourier transform on Cl_3,0 such as differentiation properties, and the Plancherel theorem. Finally, we apply the Clifford Fourier transform properties for proving an uncertainty principle for Cl_3,0 multivector functions.