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Remediation of two polluted soils from a northern Italian industrial site heavily contaminated with organic contaminants was attempted here by subjecting soils first to addition with an exogenous humic acid (HA), and, then, to an oxidation reaction catalyzed by a water-soluble iron-porphyrin (FeP). An expected decrease of detectable organic pollutants (>50%) was already observed when soils were treated only with the H2O2 oxidant. This reduction was substantially enhanced when oxidation was catalyzed by iron-porphyrin (FeP+H2O2) and the largest effect was observed for the most highly polluted soil. Even more significant was the decrease in detectable pollutants (70-90%) when soils were first amended with HA and then subjected to the FeP+H2O2 treatment. This reduction in extractable pollutants after the combined HA+FeP+H2O2 treatment was due to formation of covalent CC and COC bonds between soil contaminants and amended humic molecules. Moreover, the concomitant detection of condensation products in soil extracts following FeP addition confirmed the occurrence of free-radical coupling reactions catalyzed by FeP. These findings indicate that a combined technique based on the action of both humic matter and a metal-porhyrin catalyst, may become useful to quantitatively reduce the toxicity of heavily contaminated soils and prevent the environmental transport of pollutants., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Considering the increasing impact of bacterial biofilms on human health, industrial and food-processing activities, the interest in the development of new approaches for the prevention and treatment of adhesion and biofilm formation capabilities has increased. A viable approach should target adhesive properties without affecting bacterial vitality in order to avoid the rapid appearance of escape mutants. It is known that marine bacteria belonging to the genus Pseudoalteromonas produce compounds of biotechnological interest, including anti-biofilm molecules. Pseudoalteromonas haloplanktis TAC125 is the first Antarctic Gram-negative strain whose genome was sequenced. In this work the anti-biofilm activity of P. haloplanktis supernatant was examined on different staphylococci. Results obtained demonstrated that supernatant of P. haloplanktis, grown in static condition, inhibits biofilm of Staphylococcus epidermidis. In order to define the chemical nature of the biofilm-inhibiting compound, the supernatant was subject to various treatments. Data reported demonstrated that the biologically active component is sensible to treatment with sodium periodate suggesting its saccharidic nature., (Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Removal of the agrochemical simazine from polluted waters through adsorption by zeolite Y in its protonic form was studied. The investigated parameters were: pH, time, initial simazine concentration and solid/liquid ratio. An iterative process of simazine removal from waters is proposed, featuring: (i) final agrochemical concentration well below 0.05 mg/dm(3), the maximum concentration allowed by Italian laws in wastewaters; (ii) regeneration of the adsorbent by a few minutes thermal treatment in air at about 500°C, which results in the combustion of simazine without damage of the adsorbent; (iii) destruction of the agrochemical compound by combustion., (Copyright © 2012 Elsevier B.V. All rights reserved.)

All tetrameric hemoglobins from Antarctic fish, including that from Trematomus bernacchii, HbTb form in the ferric state, promptly and distinctively from all the other tetrameric hemoglobins, a mixture of aquo-met at the α subunits and bis-histidyl adduct (hemichrome) at the β subunits. The role of the tertiary and quaternary structure in the hemichrome formation is unknown. Here we report the cloning, expression, purification, spectroscopic and computational characterization of the β-chain of HbTb (β-HbTb). Similarly to the human β-chains, β-HbTb self-assembles to form the homotetramer β(4)-HbTb; however, the latter quantitatively forms reversible ferric and ferrous bis-histidyl adducts, which are only partially present in the human tetramer (β(4)-HbA). A molecular dynamics study of the isolated β subunit of the two Hbs indicates that the ability to form hemichrome is an intrinsic feature of the chain; moreover, the greater propensity of β-HbTb to form the bis-histidyl adduct is probably linked to the higher flexibility of the CD loop region. On the bases of these experimental and computational results on the isolated chain, the influence of the quaternary structure on the stability of the endogenous ferrous and ferric hexa-coordination is also discussed., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

A class II hybrid sol-gel material was prepared starting from zirconium(IV) propoxide and 2,4-pentanedione and its catalytic activity in the removal of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) was revealed. The thermal and structural characterization, performed by thermogravimetry, differential thermal analysis, and diffuse reflectance Fourier transform infrared spectroscopy, demonstrated the hybrid nature of the material. The structure of the material can be described as a polymeric network of zirconium oxo clusters, on the surface of which large part of Zr(4+) ions are involved in strong complexation equilibria with acetylacetonate (acac) ligands. The incubation of MCPA in the presence of this material yielded an herbicide removal fraction up to 98%. A two-step mechanism was proposed for the MCPA removal, in which a reversible first-order adsorption of the herbicide is followed by its catalytic degradation. The nature of the products of the MCPA catalytic degradation as well as the reaction conditions adopted do not support typical oxidation pathways involving radicals, suggesting the existence of a different mechanism in which the Zr(4+):acac enol-type complex can act as Lewis acid catalyst.

Two mesoporous metal oxides, Al(2)O(3) and Fe(2)O(3), were evaluated as regards their ability to remove simazine, a highly persistent herbicide of s-triazines, using a batch equilibrium method. The effect of several experimental parameters such as pH, contact time, initial concentration and sorbent dosage on the sorption of the herbicide was investigated. The maximum sorption of simazine on Al(2)O(3) and Fe(2)O(3) was observed at pH 6.5 and 3.5, respectively. The different sorption capacities of the two oxides were explained considering a set of factors affecting the sorption process such as the surface area and the porosity. The kinetics of sorption on both oxides was described using a pseudo second-order model. The sorption of simazine on Fe(2)O(3) was faster in comparison to that observed on Al(2)O(3). It was shown that aluminum oxide can be regenerated by incineration, and consequently can be considered for industrial treatment systems designed to mitigate the pesticide pollution in the aquatic environments., (Copyright © 2011 Elsevier B.V. All rights reserved.)

A single-stage sol-gel route was set to entrap yeast cells of Lipomyces starkeyi in a zirconia (ZrO(2)) matrix, and the remediation ability of the resulting catalyst toward a phenoxy acid herbicide, 4-chloro-2-methylphenoxyacetic acid (MCPA), was studied. It was found that the experimental procedure allowed a high dispersion of the microorganisms into the zirconia gel matrix; the ZrO(2) matrix exhibited a significant sorption capacity of the herbicide, and the entrapped cells showed a degradative activity toward MCPA. The combination of these effects leads to a nearly total removal efficiency (>97%) of the herbicide at 30 °C within 1 h incubation time from a solution containing a very high concentration of MCPA (200 mg L(-1)). On the basis of the experimental evidence, a removal mechanism was proposed involving in the first step the sorption of the herbicide molecules on the ZrO(2) matrix, followed by the microbial degradation operated by the entrapped yeasts, the metabolic activity of which appear enhanced under the microenvironmental conditions established within the zirconia matrix. Repeated batch tests of sorption/degradation of entrapped Lipomyces showed that the removal efficiency retained almost the same value of 97.3% after 3 batch tests, with only a subsequent slight decrease, probably due to the progressive saturation of the zirconia matrix.

We propose a direct test of the existence of gauge duals for nonsupersymmetric asymptotically free gauge theories developing an infrared fixed point by computing the S parameter in the electric and dual magnetic description. In particular we show that at the lower bound of the conformal window the magnetic S parameter, i.e., the one determined via the dual magnetic gauge theory, assumes a simple expression in terms of the elementary magnetic degrees of freedom. The results further support our recent conjecture of the existence of a universal lower bound on the S parameter and indicates that it is an ideal operator for counting the active physical degrees of freedom within the conformal window. Our results can be directly used to unveil possible four-dimensional gauge duals and constitute the first explicit computation of a nonperturbative quantity, in the electric variables, via nonsupersymmetric gauge duality.

Lipomyces starkey were able to survive and proliferate in the presence of olive oil mill wastewaters (OMW), a medium difficult to process by biological treatments, due to the antimicrobial activities of their phenolic components. The microorganisms were grown in the presence of undiluted OMW, without external organic supplements, producing a significant reduction of both the total organic carbon (TOC) and the total phenols content. The OMW treated by L. starkey showed a significant increase of the germination index. The preliminary dilution of OMW enhanced the reduction of polluting components of OMW, leading to a complete TOC removal, as well as to lower levels of residual phenols. The activities of extracellular lipases and esterases significantly increased in the course of the OMW fermentation. A significant increase in lipid yield was observed in L. starkey in the course of the OMW treatment, particularly enhanced when the feedstock was preliminarily diluted. The fatty acid distribution showed a prevalence of oleic acid, demonstrating the potential of L. starkeyi as a source of lipids to be used as a feedstock for the synthesis of II generation biodiesel.

A study was performed to assess the sorption capacity of the phenoxy acid herbicide, MCPA, on two mesoporous oxides, Al(2)O(3) and Fe(2)O(3,) by using a batch equilibrium method. Effects of pH, contact time, initial concentration and sorbent dosage on the sorption of the herbicide were investigated. The collected data evidenced the greater sorption efficiency of Al(2)O(3) with respect to Fe(2)O(3). These results can be explained by considering the specific mesoporous structure of Al(2)O(3) together with the greater value of surface area. MCPA is assumed to be bound to Al(2)O(3) and Fe(2)O(3) by a combination of ionic and ion-dipole bonding. Both oxides present as sorbents for a fast and highly efficient removal of MCPA from contaminated waters. For the first time the possible use of mesoporous metal oxides to remove MCPA from contaminated wastewaters identifies these sorbents as suitable filters for the decontamination of point sources.

A comparative study was performed on the sorption capacity of the phenoxy acid herbicide cyhalofop on polymerin (from olive oil mill effluents), ferrihydrite, and a ferrihydrite-polymerin complex, by using a batch equilibrium method. The most efficient sorbent showed to be ferrihydrite followed by the ferrihydrite-polymerin complex and polymerin. Cyhalofop acid bound to ferrihydrite by a combination of ionic and ion-dipole bonding, whereas the same herbicide bound to the ferrihydrite-polymerin complex by ionic bonding and to polymerin by hydrogen bonding. Simulated wastewaters contaminated with cyhalofop acid were completely purified by two sorption cycles on ferrihydrite and five cycles on the ferrihydrite-polymerin complex, whereas the same wastewaters maintained a constant residue even after five sorption cycles on polymerin. For the first time, the possible use of a mineral (ferrihydrite) and an organo-mineral complex (ferrihydrite-polymerin) as a filter for the control of the herbicide contamination in point sources is proposed and briefly discussed.

Three alpha-elicitins, named hibernalin1, hibernalin2 and hibernalin3 (hib1, hib2 and hib3, respectively), were isolated by reverse phase-low-pressure liquid chromatography from culture filtrates of Phytophthora hibernalis Carne 1925, the causal agent of citrus lemon brown rot. Hib1 proved to be identical to syringicin previously isolated from culture filtrates of Phytophthora syringae. Hib2 and hib3 shared the same primary structure with hib1, but contained, at position 50, Met sulphoxide or sulphone, respectively. By SDS-PAGE, the three proteins showed the same electrophoretic mobility, corresponding to about 10 kDa. Exact M(r) values were obtained by MALDI-TOF-MS (10,194.82 for hib1, 10,209.33 for hib2 and 10,223.80 for hib3), while by ESI-MS an M(r) value of 10,194.90 was found for hib1 and no results for hib2 and hib3. The hibernalin forms showed a high propensity to self-association, after exposure to acetonitrile. Hib1 showed to be active in both the hypersensitivity response and electrolytes leakage assays; the sample containing hib1 and hib2 was only weakly active in the first assay and inactive in the second assay, while the sample containing all three hibernalin forms proved to be inactive in both tests. It is proposed that the different activities of the three hibernalin samples could be very likely attributed to both Met50 oxidation and aggregation.

A hydroxytyrosol triacetyl derivative was very efficiently produced as a highly pure stabilized antioxidant compound by a short treatment of olive mill waste water (OMWW) organic extracts, rich in hydroxytyrosol, with an acetylating mixture composed of HClO4-SiO2 and Ac2O (Chakborti and Gulhane reaction), in mild and safe conditions. A successive single step of middle pressure liquid chromatography (MPLC) purification of the reaction product was performed, with an overall yield of 35.6%. (This process, including both the Chakborti and Gulhane reaction and the MPLC purification, is protected by an international patent under PCT/IT2005/000781.) The o-diphenol triacetyl derivative was also produced by direct reaction of hydroxytyrosol, previously purified by MPLC, with HClO4-SiO2 and Ac2O, with an overall yield of 29.5%. A further procedure for the production of the hydroxytyrosol triacetyl derivative was consistent with the direct treatment of raw OMWW with the acetylating agent and a single step of MPLC purification, with an overall yield of 27.6%. The purified natural triacetylhydroxytyrosol confirmed the same strong protective effects against the oxidative stress in human cells as the corresponding synthetic compound, likely because of the biochemical activation of the acetyl derivative into the active parent hydroxytyrosol by esterases. We therefore propose the utilization of OMWW for recovering hydroxytyrosol as a natural antioxidant in a chemically stabilized form, with a good yield, which can be potentially used as a nontoxic functional component in nutritional, pharmaceutical, and cosmetic preparations.

Chemically stable di- and triacetyl derivatives of the natural o-diphenol antioxidant hydroxytyrosol were synthesized, and their chemical and biological antioxidant activities were assessed in comparison with that of the native synthetic compound. The chemical antioxidant activity of the selected compounds was evaluated by measuring the ferric reducing antioxidant power (FRAP). The data clearly indicate that, as expected, the hydroxytyrosol analogues, modified in the o-diphenolic ring, are devoid of any chemical antioxidant activity. On the contrary, both acetyl derivatives, at micromolar concentrations, equally protect against tert-butylhydroperoxide-induced oxidative damages in Caco-2 cells and human erythrocytes. This paper for the first time reports that chemically stable hydroxytyrosol acetyl derivatives, although devoid of chemical antioxidant activity, are as effective as the parent compound in protecting human cells from oxidative stress-induced cytotoxicity, after metabolization by esterases at the intestinal level, suggesting their possible utilization in either nutritional (functional food), cosmetic, or pharmaceutical preparations.

A study on the individual sorption of Cr(III), Cu, and Zn on polymerin, the humic-acid-like fraction of olive mill wastewater, and its derivatives, K-polymerin and an Fe(OH)x-polymerin complex, showed that these heavy metals were strongly sorbed on polymerin and K-polymerin in the order Cr(III) > Cu > Zn. The sorption on Fe(OH)x-polymerin was to a lower extent compared with that of the other two sorbents, but to a higher extent compared with ferrihydride [Fe(OH)x]. Combined atomic absorption spectrometry and diffuse reflectance infrared Fourier transform spectroscopy analyses showed that the selected heavy metals were individually sorbed on polymerin by means of a cation exchange mechanism, which was consistent with the replacement of Ca, Mg, K, and H bound to the carboxylate groups of the biosorbent and the concomitant chelation of the heavy metals by the OH groups of polymerin polysaccharide component. In binary combination and equimolar ratio, Cu was sorbed by polymerin more selectively than Zn. In ternary combination and equimolar ratio, Cr(III), Cu, and Zn were sorbed by polymerin in the order Cr(III) > Cu > Zn. The sorbing capacity of Zn and Cu was strongly influenced by Cr(III), whereas the sorbing capacity of Cr(III) was not affected bythe presence of the other two metals. The overall sorbing capacity of the binary and ternary mixtures of the three metals on polymerin proved to be considerable and much greater than that on Fe(OH)x-polymerin. Simulated wastewaters contaminated with Cu and Zn were purified after three sorption cycles by polymerin renewed at each cycle, whereas those containing a mixture of Cr(III), Cu, and Zn showed residues of Zn after five cycles. We briefly discuss environmental and industrial advantages for a possible exploitation of polymerin.

We construct an effective Lagrangian which illustrates why color deconfines when chiral symmetry is restored in hot gauge theories with quarks in the fundamental representation. For quarks in the adjoint representation we show that, while deconfinement and the chiral transition do not need to coincide, entanglement between them is still present. Extension to the chemical potential driven transition is discussed.

We show that all of the relevant features of a phase transition can be determined using a non-order-parameter field which is a physical state of the theory. This fact allows us to describe the deconfining transition of the pure Yang-Mills theory via the physical excitations rather than using the Polyakov loop.

The transformation by an oxidoreductase (a laccase from Rhus vernificera) of a mixture of four phenols (catechol, methylcatechol, m-tyrosol and hydroxytyrosol) that simulates a typical wastewater derived from an olive oil factory was investigated. Results achieved in this study confirm that laccase-mediated transformation of phenols depends on the nature and the initial concentration of the involved phenol, the time course of the reaction, and mainly, on the complexity of the phenolic incubation mixture. Actually, the four phenols each have a completely different response to enzyme action both in terms of quantitative and kinetic transformation. For example, after 24-h incubation, methylcatechol was completely removed, whereas 30% of untransformed hydroxytyrosol and catechol and more than 65% of m-tyrosol were still present in the reaction mixture. A reduction of enzyme activity occurred for all phenols after enzymatic oxidation. No correspondence between phenol transformation and disappearance of enzymatic activity was observed, thus suggesting that different mechanisms are probably involved in the laccase-mediated transformation of the four phenols. The behavior of phenols became more complex when an increasing number of phenols was present in the reaction mixture, and even more so when different concentrations of phenols were used. Competitive effects may arise when more than one phenol is present in the reaction solution and interacts with the enzyme.

The influence of four pesticides, e.g. glyphosate, paraquat, atrazine, and carbaryl, on the activities of invertase, urease and phosphatase of twenty-two soils, numbered as 1-22, was investigated. Soils displayed a general variability of enzyme activities with invertase being more abundant than urease and phosphatase in the order listed. The addition of glyphosate and paraquat activated invertase and urease activities in several soils. Increments of invertase activity ranged from a very low increase (+4%) up to +204% in soils 11 and 14, respectively. Smaller increases were measured for urease. A general inhibitory effect (from 5% to 98%) was observed for phosphatase in the presence of glyphosate. The effects of atrazine and carbaryl on the three soil enzymes were evaluated against that exhibited by methanol, the solvent used for their solubilization. In almost all soils, atrazine further inhibited invertase activity with respect to the inhibitory effect shown by methanol. By contrast, consistent activation effects (from 61% to 10217%) were measured for urease with methanol alone and/or methanol-pesticide mixtures. Contradictory results were observed with phosphatase. Similarities found between the results obtained with enzymes in soils and those measured with synthetic enzyme complexes (e.g. free enzymes and/or clay-, organo-, and organo-clay-enzyme complexes) exposed to the same pesticides allowed some relationships between responses of soil enzymes to pesticides and soil properties to be hypothesized.

An Al(OH)x-montmorillonite (chlorite) complex (AM18) was prepared and 2,4-dichlorophenoxyacetic acid (2,4-D) sorbed to saturation. After several washing cycles the 'strongly sorbed' 2,4-D was 507 micrograms g-1 AM18. The bioavailability of sorbed 2,4-D was assessed in a minimal salts medium with the AM18-2,4-D as the sole C and energy source. Over a 28-day period a Pseudomonas sp. degraded 23% more of the sorbed 2,4-D than could be accounted for by desorption from AM18 in the non-inoculated controls. Possible explanations for the increase in bioavailability are presented.

Ultrasound assessment of septum thickness is useful in twin pregnancies for predicting the type of placentation. In fact, its greater or lesser acoustic resonance distinguishes monochorionic or dichorionic pregnancies. This makes adoption of therapeutic measures more secure in the event of pathology involving only one of the two fetuses.