Search

International audience; Poster PresentationsP-20 | Omics approaches in toxicology

This article investigates the influence of the macroeconomic environment on corporate leverage. Using panel data of European listed SMEs, we examine the relationship between capital structure and country-level total factor productivity (TFP), GDP growth, interest rates and stock market development across firm categories (micro, small, and medium) and monetary regimes (EMU and non-EMU countries) for the period 2005–2015. By performing a dynamic panel data analysis into a vector error correction framework, along with several model specifications and robustness tests, we provide new evidence that country-level TFP is an important determinant of capital structure choice, while its impact depends on the institutional environment (inside the EMU or not). Although there are both short-run and long-run dynamic relationships between the corporate leverage and the macroeconomic factors, to EMU or not to EMU is also evident when looking at the three size categories. Overall, our results suggest that all SMEs are not the same, and the determinants of their capital structure vary across size categories. © 2020 John Wiley & Sons, Ltd.

This paper employs econometric techniques in order to examine the role of political risk on the capital structure decisions of European listed SMEs, during a period which fully captures the Euro zone debt crisis and aspects of political risk due to the recession and its over-indebtedness. We find that political risk decreases significantly SMEs leverage via different and significant transmission channels. Very small (micro) enterprises are decreasing more significantly their leverage at times of political risk. The strength of the creditor’s rights acts as a proxy for the possible effects of the political risk. Political risk combined with corruption has a positive effect on firm leverage. © 2020 Informa UK Limited, trading as Taylor & Francis Group.

This article investigates the capital structure dynamics of European SMEs by assessing the impact of firm-specific, institutional, and macroeconomic factors over the period 2005–2015, including the European Sovereign Debt Crisis (ESDC). In this setup, we perform a dynamic panel data analysis, along with several model specifications and robustness tests on listed SMEs of EU-28, dividing them into firm categories (micro, small, and medium) and country groups (core, periphery, high technology, and new EU member countries). We find that the effect of capital structure determinants do not differ significantly across size and country groups. The results suggest that profitability, asset structure, and size have been the driving forces of listed SME’s leverage, regardless of the size of the companies and the country group. At a macroeconomic and institutional level, taxation is the most significant variable for all the subgroups. Finally, the ESDC seems to increase the leverage of the listed SMEs in the periphery and the new member states countries, leaving the core countries practically unaffected. © 2019 Journal of the Canadian Council for Small Business and Entrepreneurship/Conseil Canadien de la PME et de l’entrepreneuriat.

Maritime transport has been a crucial input for the growth of the Greek economy given that the Greek fleet is one of largest merchant fleets in the world. However, the impact of the local and international business cycle on Greek maritime transport is inadequately researched, so far, in the literature. In this context, the present paper investigates the key determinants of maritime transport fluctuations in the three major ports of the Greek hinterland, taking into account a number of variables for the 1998–2015 time-span, capturing, at least partly, the global financial crisis and the local crisis, as well. To this end, various relevant quantitative techniques have been used, such as Granger causality, Dufour and Renault multistep causality and SURE system estimation. Our main finding is that Greek maritime transport traffic, as expressed through the cargo volumes of the three major ports of Piraeus, Volos and Thessaloniki, has not been influenced by the Greek business cycle, implying that the country’s maritime sector is practically independent of the macroeconomic conditions of the total economy. Clearly, future and more extended research would be relevant in the direction of applying the aforementioned approach to other EU countries of the Mediterranean. © 2017, Springer-Verlag GmbH Germany.

The detailed environment of the essential cofactor pyridoxal 5'-phosphate in glycogen phosphorylase b, resulting from crystallographic refinement at 1.9-A resolution, is described. The pyridoxal ring is buried in a nonpolar site containing three aromatic rings while the 5'-phosphate group is highly solvated and makes only three direct contacts to the protein. The pyridine nitrogen interacts via a water with protein atoms. The crystal structures of three active derivatives of phosphorylase reconstituted with 5'-deoxypyridoxal 5'-methylenephosphonate (PDMP), 6-fluoropyridoxal 5'-phosphate (6-FPLP), and pyridoxal (PL) in place of the natural cofactor have been determined at 2.5-A resolution. The results for PDMP-phosphorylase show a closer proximity of the phosphonate group to the NZ atom of a lysine (Lys-574) than that observed in the native enzyme, consistent with /sup 31/P NMR studies that have shown a change in ionization state of the phosphonate group compared to the native cofactor phosphate. The replacement of the polar 5'-ester linkage by a CH/sub 2/ group results in a small shift of a water and its hydrogen-bonded tyrosine (Tyr-648). In 6-FPLP-phosphorylase the fluorine is accommodated with no significant change in structure. In PL-phosphorylase co-crystallized with 6.5 mM phosphite and 50 mM glucose, the phosphite anion binds to a site thatmore » is close to but distinguishable from the 5'-phosphate site of the coenzyme. In the presence of glucose, phosphite binding provides significant stability to the crystal structure of PL-phosphorylase (T state) through a number of polar interactions. The implications of these results on the role of PLP in phosphorylase are discussed.« less

We present an investigation of magnetic ordering in the two-dimensional S=1/2 quantum magnet Cu(Pz)_2(ClO_4)_2 using specific heat and zero field muon-spin relaxation (\mu^+SR). The magnetic contribution to the specific heat is consistent with an exchange strength of 17.7(3) K. We find unambiguous evidence for a transition to a state of three-dimensional long range order below a critical temperature T_N=4.21(1) K using \mu^+SR even though there is no feature in the specific heat at that temperature. The absence of a specific heat anomaly at T_N is consistent with recent theoretical predictions. The ratio of T_N/J=0.24 corresponds to a ratio of intralayer to interlayer exchange constants of |J'/J|=6.8x10^-4, indicative of excellent two-dimensional isolation. The scaled magnetic specific heat of [Cu(Pz)_2(HF_2)]BF_4, a compound with an analogous structure, is essentially identical to that of Cu(Pz)_2(ClO_4)_2 although both differ slightly from the predicted value for an ideal 2D S=1/2 Heisenberg antiferromagnet., Comment: 7 pages, 4 figures

Vehicle exhaust emission standards have been tightened in the EU for several decades now, in order to protect health and the environment. This has led to a substantial decrease in total pollutant emissions, despite the growing volumes of passenger and freight transport. However, national emissions, particularly of NOx, exceed the ceilings accorded under the Gothenburg Protocol of the UNECE's Convention on Long-Range Transboundary Air Pollution (LRTAP) (EEA 2012) in twelve EU Member States. The main reasons for such exceedances are that more diesel cars have been sold than originally predicted when fixing the targets, and that diesel cars emit much more than expected under real-world driving conditions. The latter appears as a consequence of the effort to achieve high fuel efficiency. While this has largely helped to control CO2 emissions, it was to the detriment of NOx. In this study we estimate what the impact of the different vehicle emission standards has been so far and to predict what the impact of upcoming emission standards will be in the future, using the best current knowledge on road transport activity statistics and emission factors in Europe. We present several sensitivity calculations to reflect the considerable uncertainty about the real-driving NOx emissions of diesel light duty vehicles. The results of this work can be useful in designing both limits for upcoming standards but also in assessing the impact of deviating from such limits. This is necessary in both deciding on the next steps of emission control policy and to relevant air quality prediction models.

Aim of our study was to evaluate BNP as early cardiotoxicity biomarker after completion of chemotherapy in twenty children with hematological malignancies at diagnosis (t=0) and after completion of intensive chemotherapy (t=1).Demographic data, underlying disease, cumulative anthracyclines dose, measurement of serum BNP and evaluation of systolic function of left ventricle with ejection fraction (EF) and shortening fraction (FS) in both times . Pathological values for EF and FS were found in 4 (20%) and 1 (5%) patient at t=1, while respective values were normal at diagnosis.Mean BNP values at t=0 were 59.09±19.95 pg/mL and differ significantly from values at t=1 (153.22±29.14 pg/mL) (P=0.04). Mean value of EF also differed significantly (75.42±4.11% vs. 69.87±10.51%, P=0.04). No statistic difference was found regarding FS values at both (P=0.102).Present data indicate that anthracyclines related cardiotoxicity is registered in children with hematological malignancies and BNP represents a useful biomarker of myocardial dysfunction.

Children with haematological malignancies such as acute lymphoblastic leukaemia (ALL) may have alteration of bone mineral metabolism therefore increased risk for osteopenia and osteoporosis.The purpose of this study was to examine the alterations of bone mineral metabolism in two groups of children (n=42) according to immunophenotyping (B-cell type, T-cell type) both quantitative (bone mineral density z-scores) and qualitative (serum osteocalcin - OC and carboxyl-terminal telopeptide of human type I collagen - ICTP) during diagnosis (T=0), after the intensified chemotherapy period (T=0.5) and the consolidation period (T=1).According to our results 15 patients had osteopenia and 1 child developed osteoporosis at T=0.5 and 13 patients had osteopenia at T=1. Mean BMD z-score was significantly decreased in both groups during chemotherapy and especially statistically significant decline of T-cell type ALL group compared with B-cell type ALL patients. OC mean level remains in low levels for both groups reaching in plateau during chemotherapy and ICTP level was increased in T-cell type ALL group of patients compared with B-cell type in both periods of chemotherapy.It seems that not only the combination of chemotherapeutic agents but also the cell lineage of ALL are important parameters of altering bone mineral metabolism.

Candida hellenica var. hellenica (teleomorph Zygoascus meyerae) is a member of the genus Zygoascus that comprises species isolated from environmental sources such as damaged grapes. A case of a possible pneumonia due to this uncommon yeast in a pediatric oncology patient suffering from acute myeloid leukemia is described. To our knowledge, this is the first report concerning the isolation of the species from a pediatric patient and the second in humans. © 2011 ISHAM.

The question of the nature of superconductivity in boron-doped diamond (synthesized at high pressures and high temperatures) is still open. Here we present consistent measurements of resistivity and specific-heat on two samples containing pure 13C and 12C, revealing a 0.2 K shift of the superconducting transition temperature Tc. Hallcoefficient measurements confirm equal charge-carrier concentrations in both samples. The results are interpreted as a carbon-isotope effect more than two times larger than expected from the most simple BCS model for phonon-mediated superconductivity. Additional analyses of microstructure and exact boron content of the superconducting material show the presence of highly boron-enriched amorphous boundaries between the grains. For these investigations highresolution transmission-electron microscopy and electron-energy-loss spectroscopy were used.

The measured thermodynamic phase diagram of the quasi-two-dimensional magnet [Cu(HF2)(pyz)2]BF4 (pyz=pyrazine=N2C4H4) exhibits an unusual nonmonotonic dependence of the Neel temperature TN as a function of magnetic field H. The nonmonotonic behavior of TN(H) results from two competing effects induced by the field: while H suppresses the amplitude of the order parameter by polarizing the spins along a given direction, it also reduces the phase fluctuations by changing the order parameter space from the sphere S2 to the circle S1. The latter effect dominates at low fields only if the system is close enough to its lower critical dimension (dc = 2), i.e., when fluctuations become important. Our theoretical results reproduce the measured phase diagram and demonstrate that this unusual effect is realized in [Cu(HF2)(pyz)2]BF4.

Results of high-field ESR and magnetization studies of the new spin-1 Haldane-chain material [Ni(C2H8N2)2NO2](BF4) (NENB) are reported. A definite signature of the Haldane state in NENB was obtained. From the analysis of the frequency-field dependence of magnetic excitations in NENB, the spin-Hamiltonian parameters were calculated, yielding \Delta/k_{B} = 17.4~K, g_{\parallel}=2.14, D/k_{B}=7.5~K, and |E/k_{B}|=0.7~K for the Haldane gap, g factor and the crystal-field anisotropy constants, respectively. The presence of fractional S=1/2 chain-end states, revealed by ESR and magnetization measurements, is found to be responsible for spin-glass freezing effects. In addition, extra states in the excitation spectrum of NENB have been observed in the vicinity of the Haldane gap, which origin is discussed.