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In this article, gold is analyzed from an investment perspective as an asset that allows you to increase your wealth. The analysis is twofold. First, it is about examining to what extent changes in gold prices in the world markets translate into changes in the prices of shares of companies that extract gold. second, it was checked whether there is a financial leverage effect, which in this case means that changes in the price of shares of gold mining companies are greater than changes in the price of gold itself. Methodically, the sharpe model was used and two basic parameters of the model were estimated, i.e. the intercept (alpha), and the beta coefficient as a measure of systematic risk, for the gold market and the equity market of gold mining companies and etFs based on these companies. the research carried out in accordance with the logic of the sharpe model shows that the obtained value of the alpha parameter for the stock market was positive, while for the gold market it was negative. at the same time, higher levels of this parameter are beneficial to the investor, which means that an advantage of the stock market over the gold market exists. In turn, the estimated beta for the stock market is much lower than for the gold market. the systematic risk level for stocks is 0.45, and for the gold market it is 1.98, which is a significant difference. the stocks of gold mining companies can be classified as defensive against the stock market (the rate of return of the gold mine stock is insensitive to market movements) and aggressive against the gold market (the rate of return of the gold mine shares reacts more strongly than the movement in the price of gold). [ABSTRACT FROM AUTHOR]

Diclofenac (DC) [2-(2,6-Dichloroanilino)phenyl]acetic acid,) and aceclofenac (AC) 2-[2-[2-[(2,6-dichlorophenyl)amino]phenyl]acetyl]oxyacetic acid in substantia were subjected to ionizing radiation in the form of a beam of high-energy electrons from an accelerator in a standard sterilization dose of 25 kGy and higher radiation doses (50–400 kGy). We characterized non-irradiated and irradiated samples of DC and AC by using the following methods: organoleptic analysis (color, form), spectroscopic (IR, NMR, EPR), chromatographic (HPLC), and others (microscopic analysis, capillary melting point measurement, differential scanning calorimetry (DSC)). It was found that a absorbed dose of 50 kGy causes a change in the color of AC and DC from white to cream-like, which deepens with increasing radiation dose. No significant changes in the FT-IR spectra were observed, while no additional peaks were observed in the chromatograms, indicating emerging radio-degradation products (25 kGy). The melting point determined by the capillary method was 153.0 °C for AC and 291.0 °C for DC. After irradiation with the dose of 25 kGy for AC, it did not change, for DC it decreased by 0.5 °C, while for the dose of 400 kGy it was 151.0 °C and 286.0 °C for AC and DC, respectively. Both NSAIDs exhibit high radiation stability for typical sterilization doses of 25–50 kGy and are likely to be sterilized with radiation at a dose of 25 kGy. The influence of irradiation on changes in molecular dynamics and structure has been observed by 1H-NMR and EPR studies. This study aimed to determine the radiation stability of DC and AC by spectrophotometric, thermal and chromatographic methods. A standard dose of irradiation (25 kGy) was used to confirm the possibility of using this dose to obtain a sterile form of both NSAIDs. Higher doses of radiation (50–400 kGy) have been performed to explain the changes in DC and AC after sterilization. [ABSTRACT FROM AUTHOR]

Introduction: Currently, mobile phones and Wi-Fi are the most commonly used forms of telecommunication. The popularity of mobile telecommunications has made it necessary to investigate the problem more comprehensively and cautiously assess the possible risks, because never before in history has such a substantial proportion of the population been exposed to microwaves at comparably high levels. Some studies indicate that the high frequency electromagnetic radiation emitted by mobile phone and Wi-Fi connections can have a negative effect on human health, and can cause cancer. Objective: The aim of the study was to investigate the influence of the radiofrquency electromagnetic field (RF-EMF) on the metaboloc activity and morphology of normal human cells (fibroblasts) and cancer cells (prostate cancer cells). Material and methods: The cell cultures (human fibroblasts and prostate cancer cells) were exposed to RF-EMF at the frequency of 2.5 GHz for 24, 48 and 72h. To quantify changes in cell viability, the Cell Counting Kit - 8 was used. Results: It was found that the RF electromagnetic field exposure caused a significant decrease in the viability of fibroblasts, and a significant increase in cancer cells. Morphological analysis did not show significant changes in both cell lines after exposure to RF-EMF. Conclusions: On the basis of the obtained results, the hypothesis can be formulated that a high frequency electromagnetic field can have harmful effects on human cells. [ABSTRACT FROM AUTHOR]

A study concerning the image quality in electron paramagnetic resonance imaging in two-dimensional spatial experiments is presented. The aim of the measurements was to improve the signal-to-noise ratio (SNR) of the projections and the reconstructed image by applying modulation amplitude higher than the radical electron paramagnetic resonance linewidth. Data were gathered by applying four constant modulation amplitudes, where one was below 1/3 (Amod = 0.04mT) of the radical linewidth (◢Bpp= 0.14mT). Three other modulation amplitude values were used in this experiment, leading to undermodulated (Amod<1/3 ◢Bpp), partially overmodulated (Amod∼1/3 ◢Bpp) and fully overmodulated (Amod>>1/3 ◢Bpp) projections. The advantages of an applied overmodulation condition were demonstrated in the study performed on a phantom containing four shapes of 1.25mM water solution of 2, 2, 6, 6-tetramethyl-1-piperidinyloxyl. It was shown that even when the overmodulated reference spectrum was used in the deconvolution procedure, as well as the projection itself, the phantom shapes reconstructed as images directly correspond to those obtained in undermodulation conditions. It was shown that the best SNR of the reconstructed images is expected for the modulation amplitude close to 1/3 of the projection linewidth, which is defined as the distance from the first maximum to the last minimum of the gradient-broadened spectrum. For higher modulation amplitude, the SNR of the reconstructed image is decreased, even if the SNR of the measured projection is increased. [ABSTRACT FROM AUTHOR]

Abstract: The fourier transform infrared (FT-IR) spectra of polycrystalline orthorhombic N-benzyl-2-methyl-4-nitroaniline (BNA) were recorded in the 380–4000cm−1 region within the 11–297K temperature range while the 1H NMR spin–lattice relaxation time and the second moment of 1H NMR resonance line were measured in the 145–373K and 80–400K temperature range, respectively. Above 80K the methyl group rotation is found to be dominant among other motions and leading to a significant reduction of the proton second moment which agrees with proposed models for the rigid structure and for the internal rotations in the BNA crystal such as methyl group C3 rotation, phenyl ring rotation and trans-gauche motion of methylene group. Activation energies for the nitro and methyl group rotations were experimentally estimated by FT-IR and 1H NMR, appropriately. For comparison the potential barriers for these two group motions in BNA molecule were calculated by DFT quantum chemical methods. The role of molecular motions in the BNA crystal in the large temperature range is discussed from the point of view of its nonlinear optical properties. [Copyright &y& Elsevier]

Introduction: Currently, mobile phones and Wi-Fi are the most commonly used forms of telecommunication. The popularity of mobile telecommunications has made it necessary to investigate the problem more comprehensively and cautiously assess the possible risks, because never before in history has such a substantial proportion of the population been exposed to microwaves at comparably high levels. Some studies indicate that the high frequency electromagnetic radiation emitted by mobile phone and Wi-Fi connections can have a negative effect on human health, and can cause cancer., Objective: The aim of the study was to investigate the influence of the radiofrquency electromagnetic field (RF-EMF) on the metaboloc activity and morphology of normal human cells (fibroblasts) and cancer cells (prostate cancer cells)., Material and Methods: The cell cultures (human fibroblasts and prostate cancer cells) were exposed to RF-EMF at the frequency of 2.5 GHz for 24, 48 and 72h. To quantify changes in cell viability, the Cell Counting Kit - 8 was used., Results: It was found that the RF electromagnetic field exposure caused a significant decrease in the viability of fibroblasts, and a significant increase in cancer cells. Morphological analysis did not show significant changes in both cell lines after exposure to RF-EMF., Conclusions: On the basis of the obtained results, the hypothesis can be formulated that a high frequency electromagnetic field can have harmful effects on human cells.

Bio-based composites made of poly( l -lactic acid) (PLLA) and pine wood were prepared by melt extrusion. The composites were compatibilized by impregnation of wood with γ-aminopropyltriethoxysilane (APE). Comparison with non-compatibilized formulation revealed that APE is an efficient compatibilizer for PLLA/wood composites. Pine wood particles dispersed within PLLA act as nucleating agents able to start the growth of PLLA crystals, resulting in a faster crystallization rate and increased crystal fraction. Moreover, the composites have a slightly lower thermal stability compared to PLLA, proportional to filler content, due to the lower thermal stability of wood. Molecular dynamics was investigated using the solid-state 1 H NMR technique, which revealed restrictions in the mobility of polymer chains upon the addition of wood, as well as enhanced interfacial adhesion between the filler and matrix in the composites compatibilized with APE. The enhanced interfacial adhesion in silane-treated composites was also proved by scanning electron microscopy and resulted in slightly improved deformability and impact resistance of the composites.

A study concerning the image quality in electron paramagnetic resonance imaging in two-dimensional spatial experiments is presented. The aim of the measurements was to improve the signal-to-noise ratio (SNR) of the projections and the reconstructed image by applying modulation amplitude higher than the radical electron paramagnetic resonance linewidth. Data were gathered by applying four constant modulation amplitudes, where one was below 1/3 (Amod  = 0.04 mT) of the radical linewidth (ΔBpp  = 0.14 mT). Three other modulation amplitude values were used in this experiment, leading to undermodulated (Amod  < 1/3 ΔBpp), partially overmodulated (Amod  ~ 1/3 ΔBpp) and fully overmodulated (Amod  > > 1/3 ΔBpp) projections. The advantages of an applied overmodulation condition were demonstrated in the study performed on a phantom containing four shapes of 1.25 mM water solution of 2, 2, 6, 6-tetramethyl-1-piperidinyloxyl. It was shown that even when the overmodulated reference spectrum was used in the deconvolution procedure, as well as the projection itself, the phantom shapes reconstructed as images directly correspond to those obtained in undermodulation conditions. It was shown that the best SNR of the reconstructed images is expected for the modulation amplitude close to 1/3 of the projection linewidth, which is defined as the distance from the first maximum to the last minimum of the gradient-broadened spectrum. For higher modulation amplitude, the SNR of the reconstructed image is decreased, even if the SNR of the measured projection is increased., (Copyright © 2015 John Wiley & Sons, Ltd.)