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    POSSIBILITIES OF SOIL REGENERATION USING THE CAUSTOBIOLITES IN EARLY STAGES OF CARBONISATION

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    In this paper is presented a comparative study on the properties of the Rosia soft brown coal and a poor soil, in order to find out the possibilities of soil quality improvement for better plant growing conditions.There were determined the specific values of extractible humic acids content, technical and elemental characteristics and also for the poor soil, petrographic composition of soft brown coal with low sulphur and nitrogen was analyzed.It is revealed a big difference between the organic mass values of coal and soil but a similarity between organic components types of the two samples, as determined by petrographic analysis.These findings offered one reason for mixing a sandy soil with the studied coal. Behavior of the two types of materials was analyzed, coal and soil, during the drying process as well as the possibility to grow up plants in coal dust and improved soil.The results recommend the introduction of soft brown coal dust into the poor soils, in order to increase the content of organic mass, humic acids and microelements in soil.

    Communication: Hartree-Fock description of excited states of Hâ‚‚

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    Hartree-Fock (HF) theory is most often applied to study the electronic ground states of molecular systems. However, with the advent of numerical techniques for locating higher solutions of the self-consistent field equations, it is now possible to examine the extent to which such mean-field solutions are useful approximations to electronic excited states. In this Communication, we use the maximum overlap method to locate 11 low-energy solutions of the HF equation for the H2 molecule and we find that, with only one exception, these yield surprisingly accurate models for the low-lying excited states of this molecule. This finding suggests that the HF solutions could be useful first-order approximations for correlated excited state wavefunctions

    Towards Complex Tissues Replication: Multilayer Scaffold Integrating Biomimetic Nanohydroxyapatite/Chitosan Composites

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    This study explores an approach to design and prepare a multilayer scaffold mimicking interstratified natural tissue. This multilayer construct, composed of chitosan matrices with graded nanohydroxyapatite concentrations, was achieved through an in situ biomineralization process applied to individual layers. Three distinct precursor concentrations were considered, resulting in 10, 20, and 30 wt% nanohydroxyapatite content in each layer. The resulting chitosan/nanohydroxyapatite (Cs/n-HAp) scaffolds, created via freeze-drying, exhibited nanohydroxyapatite nucleation, homogeneous distribution, improved mechanical properties, and good cytocompatibility. The cytocompatibility analysis revealed that the Cs/n-HAp layers presented cell proliferation similar to the control in pure Cs for the samples with 10% n-HAp, indicating good cytocompatibility at this concentration, while no induction of apoptotic death pathways was demonstrated up to a 20 wt% n-Hap concentration. Successful multilayer assembly of Cs and Cs/n-HAp layers highlighted that the proposed approach represents a promising strategy for mimicking multifaceted tissues, such as osteochondral ones

    STAR Results on High Transverse Momentum, Heavy Flavor and Electromagnetic Probes

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    We summarize here recent results from the STAR collaboration focusing on processes involving large momentum transfers. Measurements of angular correlations of di-hadrons are explored in both the pseudorapidity (eta) and azimuthal (phi) projections. In central Au+Au, an elongated structure is found in the eta projection which persists up to the highest measured pT. After quantifying the particle yield in this structure and subtracting it from the near-side yield, we observe that the remainder exhibits a behavior strikingly similar to that of the near-side yield in d+Au. For heavy flavor production, using electron-hadron correlations in p+p collisions, we obtain an estimate of the b-quark contribution to the non-photonic electrons in the pT region 3-6 GeV/c, and find it consistent with FONLL calculations. Together with the observed suppression of non-photonic electrons in Au+Au, this strongly suggests suppression of b-quark production in Au+Au collisions. We discuss results on the mid-rapidity Upsilon cross-section in p+p collisions. Finally, we present a proof-of-principle measurement of photon-hadron correlations in p+p collisions, paving the way for the tomographic study of the matter produced in central Au+Au via gamma-jet measurements.Comment: 8 pages, 4 figures. Proceedings of "Quark Matter 2006", 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collision

    New data on the exploitation of obsidian in the mediterranean basin: The harbour of pyrgi and the trade in neolithic age

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    The contribution shows the first results of ongoing research on the origins and prehistoric assumptions of the well-known Etruscan and Roman harbour of Pyrgi, an ancient Ceretan harbour in southern Etruria. In the light of recent land and submarine investigations, traces of ancient frequentations and contacts dating back to the Neolithic era are emerging when the coastal morphology and environmental characteristics of the site were very different from the current ones. The Etruscan port of Pyrgi, which continues its historical history in Roman and Medieval times, appears as the heir of one or more landing points frequented perhaps already in the Middle Neolithic. As part of this contribution, around 60 obsidian finds (waste resulting from the manufacture of arrowheads) were analyzed using the LA-ICP-MS technique (Laser Ablation Inductively Coupled Plasma Mass Spectrometry). The comparison between the data obtained on the archaeological finds and the bibliographic data relating to the geological obsidians of the peri-Tyrrhenian area allowed the identification of the provenance of the finds. In particular, most of the finds can be attributed to the Aeolian area, highlighting the leading role played by the Aeolian archipelago in the development of trade of this material. Other sources of supply have been identified on the island of Palmarola and in Sardinia (Monte Arci) although with a lower incidence. The discovery of numerous findings in obsidian from overseas, which took place in the area immediately surrounding Pyrgi, offers different suggestions about the origin of the docking place, with traces of centuries-old frequentation, extended from the Neolithic to the modern era

    Inhibition of NAPDH Oxidase 2 (NOX2) Prevents Oxidative Stress and Mitochondrial Abnormalities Caused by Saturated Fat in Cardiomyocytes

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    Obesity and high saturated fat intake increase the risk of heart failure and arrhythmias. The molecular mechanisms are poorly understood. We hypothesized that physiologic levels of saturated fat could increase mitochondrial reactive oxygen species (ROS) in cardiomyocytes, leading to abnormalities of calcium homeostasis and mitochondrial function. We investigated the effect of saturated fat on mitochondrial function and calcium homeostasis in isolated ventricular myocytes. The saturated fatty acid palmitate causes a decrease in mitochondrial respiration in cardiomyocytes. Palmitate, but not the monounsaturated fatty acid oleate, causes an increase in both total cellular ROS and mitochondrial ROS. Palmitate depolarizes the mitochondrial inner membrane and causes mitochondrial calcium overload by increasing sarcoplasmic reticulum calcium leak. Inhibitors of PKC or NOX2 prevent mitochondrial dysfunction and the increase in ROS, demonstrating that PKC-NOX2 activation is also required for amplification of palmitate induced-ROS. Cardiomyocytes from mice with genetic deletion of NOX2 do not have palmitate-induced ROS or mitochondrial dysfunction. We conclude that palmitate induces mitochondrial ROS that is amplified by NOX2, causing greater mitochondrial ROS generation and partial depolarization of the mitochondrial inner membrane. The abnormal sarcoplasmic reticulum calcium leak caused by palmitate could promote arrhythmia and heart failure. NOX2 inhibition is a potential therapy for heart disease caused by diabetes or obesity
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