Crucial relationship among energy commodity prices

This study investigates the short and long run relationship between crude oil, natural gas and electricity prices in US and in European commodity markets. The relationship between energy commodities may have several implications for the pricing of derivative products and for risk management purposes. Using daily price data over the period 2001-2009 we perform a correlation analysis to study the short run relationship, while the long run relationship is analyzed using a cointegration framework. The results show an erratic relationship in the short run while in the long run an equilibrium may be identi ed having di erent features for the European and the US markets.Energy, commodities, prices.

Determination of patulin in apple juice by HPLC using a simple and fast sample preparation method

The goal of this work was to develop a simple and rapid preparation method for patulin analysis in apple juice without previous clean-up. This method combined sonication and liquid extraction techniques and was used for determination of patulin in 37 commercial apple juices available on the market in the South of Brazil. The method performance characteristics were determined using a sample obtained in a local market fortified at five concentration levels of patulin and done in triplicates. The coefficient of variation for repeatability at the fortification level of 20.70µg.L-1 was 3.53 % and the recovery 94.63 %, respectively. The correlation coefficient was 0.9996 and agrees with the requirements for a linear analytical method value. The detection limit was 0.21µg.L-1 and the quantification limit 0.70 µg.L-1. Only three of the analyzed samples were upper the allowed level of 50.00 µg.L-1 recommended for the World Health Organization.O objetivo deste trabalho foi desenvolver um método simples e rápido para preparação de amostras para análise de patulina em sucos de maçã sem "clean-up" prévio. Este método combina os métodos de extração líquida com o ultrassom e foi utilizado para a determinação de patulina em 37 amostras de suco de maçã disponíveis no mercado do sul do Brasil. Os parâmetros estatísticos para validação do método foram obtidos através de fortificação de suco de maçã, obtido no mercado local, em cinco níveis de concentração de patulina e realizadas em triplicatas. O coeficiente de variação para a repetibilidade no nível de fortificação de 20,70 µg.L-1 foi de 3,53 % e a recuperação de 94,63 %. O coeficiente de correlação foi de 0,9996 e este valor está de acordo com os requisitos de linearidade de um método analítico. O limite de detecção obtido foi de 0,21 µg.L-1 e o limite de quantificação de 0,7 µg.L-1. Somente três das amostras analisadas tiveram valores superiores ao limite de 50,00 µg.L-1 recomendado pela Organização Mundial da Saúde.FATE

Study of Magnesium Homeostasis and Intracellular Compartmentalization in Human Cells by Fluorescent Chemosensors and Synchrotron X-Ray Fluorescence

In this study, we investigated the analytical capabilities of DCHQ5, a new fluorescent chemosensor, belonging to the family of diaza-crown-hydroxyquinolines, for the quantitative assessment of total intracellular magnesium content, and its biological applications. We performed a comparative study of DCHQ5 and DCHQ1, the latter being the mother probe of the series, which showed preliminary encouraging results comparable to atomic absorption spectroscopy. We demonstrated that DCHQ5 is able to accurately quantify the total amount of Mg in a very “small” cellular population, by using a simple spectrofluorimetric assay. Furthermore, DCHQ5 demonstrated to be a versatile tool for different applications: its higher intracellular retentions allow to perform cytofluorimetric assays and two-photon confocal microscopy on whole and viable cells; its photochemical characteristic make it excitable in both UV and visible spectra, and the presence of different lifetimes allow to perform fluorescence life time imaging of intracellular Mg. DCHQ5 was also exploited for studying the involvement of magnesium in the commitment of human adipose-derived mesenchymal stem cells (hASCs) with a mixture of hyaluronic, butyric and retinoic acids (HBR). We found that in normal magnesium availability, hASCs precommitment is associated by an increase of total magnesium content during time and by a block in the G2/M phase of the cell cycle. Moreover, our results demonstrated that magnesium deprivation triggers multilineage enrichments of HBR-induced preconditioning of hASCs. The second part of this research was aimed at comparing single cells elemental analysis performed with synchrotron-based fluorescence and cell population analysis carry out by DCHQ5. We exploited innovative techniques of x-ray fluorescence microscopy by using a multimodal approach in order to achieve within the cells the spatial distribution of the concentration of magnesium and fundamental light elements for life. The combination of classical and innovative analytical techniques can shed new light in the comprehension of magnesium homeostasis

Founder succession and firm performance in the luxury industry

Top management succession may be a real threat to the long-term profitability of companies, in particular when it involves the founder whose name also identifies their brand and their products. This is extremely important in the luxury sector where loyalty, trust and the image of brands in consumers' minds may be affected by the succession process, especially when the founder has no direct heir to ensure continuity of the family firm. Through an analysis of three case studies, as well as a questionnaire distributed to active consumers of luxury products, this study aims to understand whether and how a brand can successfully survive after the death of its founder and whether the purchasing behaviour of customers changes after a founder succession takes place. Our findings reveal that the lack of a clear and structured succession plan may significantly threaten the survival of companies. In addition, our evidence indicates that the purchasing intention of luxury consumers is linked more to the bond and the values that they share with the founder than to the quality of the goods purchased. Accordingly, our results provide insights and suggestions concerning the optimal approach to follow when companies with heirless founders are planning a succession and highlights that the success and the survival of such entities is linked to consumers' perceptions of the extent to which there are continuity and alignment between the values of the founder and those of their successors

Monitoring magnesium efflux cyclic AMP-induced in HL60 cells by using a new hydroxyquinoline fluorescent chemosensor

Cellular homeostasis of magnesium is still unclear. Several studies documented the occurrence of fluxes of magnesium across the plasmamembrane within minutes from the application of metabolic or hormonal stimuli. These fluxes, however, result in limited variation of free Mg2+ intracellular concentration and large changes in total Mg content. It has been reported that a stimulation with cyclic AMP caused a movement of total magnesium within 10 min after treatment in cardiomyocytes. In this study we tested this hypothesis in HL60 leukemic cells, not excitable but highly proliferating cell model. We evaluated Mg flux by DCHQ5, the phenyl-derivative of hydroxyquinoline fluorescent probe family. We observed a drastic decrease of intracellular total magnesium in the first 3 min. We also verified that at least 10% of the total intracellular amount of magnesium moved in the supernatant of stimulated cells

Intracellular magnesium content changes during mitochondria-mediated apoptosis: in depth study of early events on mitochondrial membrane potential

A recent study showed the antitumor activity of a new indole-derivative – MM-67 – inducing mitochondria-mediated apoptosis and a decrease of intracellular magnesium (Mg) concentration in HT29 colon cancer cells. Aim of this work was to assess cellular Mg levels throughout MM-67-induced apoptosis from the early to the final stage of the process and to evaluate the correlation with mitochondrial membrane potential (ΔΨm) variations. All analysis were performed by flow cytometry: ΔΨm was assessed by using mitochondrial potential sensitive dye DiOC6, while free and total intracellular cation concentrations were assessed by using the commercial probe MagFluo4-AM (Kd=4.7 mM), and the new synthesized DCHQ5 (Kd=8.3 mM), respectively. Our results evidenced that the MM67 induced apoptosis is characterized by a direct correlation between ΔΨ and free intracellular Mg content variations

Microfluidic tools for enhanced characterization of therapeutic stem cells and prediction of their potential antimicrobial secretome

Antibiotic resistance is creating enormous attention on the development of new antibiotic-free therapy strategies for bacterial diseases. Mesenchymal stromal stem cells (MSCs) are the most promising candidates in current clinical trials and included in several cell-therapy protocols. Together with the well-known immunomodulatory and regenerative potential of the MSC secretome, these cells have shown direct and indirect anti-bacterial effects. However, the low reproducibility and standardization of MSCs from different sources are the current limitations prior to the purification of cell-free secreted antimicrobial peptides and exosomes. In order to improve MSC characterization, novel label-free functional tests, evaluating the biophysical properties of the cells, will be advan-tageous for their cell profiling, population sorting, and quality control. We discuss the potential of emerging microfluidic technologies providing new insights into density, shape, and size of live cells, starting from heterogeneous or 3D cultured samples. The prospective application of these technologies to studying MSC populations may contribute to developing new biopharmaceutical strategies with a view to naturally overcoming bacterial defense mechanisms