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In the nuclear field, the availability of effective techniques to eliminate lead pollution from wastewater is of interest both for the purposes of radiation protection from the radioactive isotope lead-210 and also for the issues related to the use of lead in the new generation reactors nowadays under study. Evidences exist of lead pollution due to the radioactive isotope lead-210 in the proximities of uranium extraction mines. In this study, two commercial granular activated carbons obtained by physical activation of coconut shell, specifically developed and selected to purify potable water from dissolved organics (GCN 1240) and for use in gold recovery systems (GCN 816 G), were studied in batch systems to evaluate their effectiveness for separation of lead (II) from aqueous solutions. A characterization of the two carbons, different in particle size, is provided through determination of their pHPZCand scanning electron microscope analysis. Adsorption of lead (II) was observed as a function of contact time, and its kinetics were fitted. Adsorption data at equilibrium were fitted by isotherm models and the maximum adsorption capacity of the carbons resulted to be 92.39 mg/g (GCN1240) and 32.08 mg/g (GCN 816 G). Experiments were carried out to investigate effects of pH on lead adsorption, evidencing that best removal performances of lead occur near pH 5.0. The present study shows that the considered commercial granular activated carbons can be successfully adopted for removal of lead (II) by adsorption from aqueous solutions. [ABSTRACT FROM PUBLISHER]

Background: Primary angioplasty is the best treatment of acute myocardial infarction but fails to achieve adequate myocardial reperfusion in 25% to 30% of patients, despite TIMI grade 3 flow. Drug treatment aimed at reducing the no-reflow phenomenon may improve myocardial salvage, thus preventing left ventricular remodeling. Our aim was to evaluate the impact of abciximab and adenosine on immediate angiographic results and on 6-month left ventricular remodeling. Methods: Ninety consecutive patients undergoing primary angioplasty with coronary stenting were randomized in a sequential alternating fashion to standard abciximab treatment (ABCX) group, intracoronary adenosine distal to the occlusion (ADO) group, or neither (CTRL) group. All patients underwent a clinical and echocardiographic follow-up at 1 and 6 months. The primary end point was the prevalence of 6-month left ventricular remodeling. Results: Baseline clinical, echocardiographic, and angiographic characteristics were similar. Mean final corrected TIMI frame count was 17 ± 9, 16 ± 12, and 23 ± 11 frames in ABCX, ADO, and CTRL patients, respectively (P = .002). Angiographic no-reflow was observed in 7%, 13%, and 17% of ABCX, ADO, and CTRL patients, respectively (P > .20). At 6 months, left ventricular remodeling occurred in 7%, 30%, and 30% of ABCX, ADO, and CTRL patients, respectively (P = .045), with a percent increase in end-diastolic volume of 5% ± 13%, 15% ± 15%, and 12% ± 18% (P = .04). Conclusions: During primary angioplasty, abciximab enhances myocardial reperfusion, translating into a reduced incidence of 6-month left ventricular remodeling. In contrast, adenosine administration improves angiographic results but does not prevent left ventricular remodeling. [Copyright &y& Elsevier]

The encapsulation of Radioactive Reactive Metallic Waste (RRMW) in ordinary Portland cement poses significant challenges due to its incompatibility with the alkaline environment of the matrix. To address this issue, magnesium phosphate cements (MPC) emerge as potential solutions for the safe and effective immobilisation of RRMWs. The radiation stability and durability of an optimised formulation have been examined for samples irradiated up to 1000 kGy, in particular concerning the leaching behaviour of the three main constituents of the cement hydration products, and on four artificially added elements used to simulate radionuclides commonly found in radioactive waste (caesium, strontium, europium, and cobalt). The mortars exhibited excellent leaching behaviour and a high mechanical resistance, even after irradiation, freeze-thaw cycles, and water immersion. No significant radiation-induced effects were observed in the mineralogical and microstructural properties of the mortars, thus supporting their stability at the examined doses. Having verified the compliance with the main Italian waste acceptance criteria, the results of this research represent an encouraging step for the future implementation of MPCs for RRMWs conditioning. • Magnesium phosphate cements are candidates for conditioning of radioactive waste • Mortars durability after irradiation, immersion, and thermal cycling was assessed • Specimens presented high mechanical resistance and leaching performance • No significant effects were observed after irradiation and immersion • Microstructural characterisations supported stability results [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Colemanite can be used as an aggregate in neutron radiation-shielding concretes. • We have investigated its high- T behavior by means of DSC, TG and XRD analyses. • The loss of structural H 2 O unambiguously occurs at least from ∼240 °C. • At T > 325 °C an irreversible amorphization towards an anhydrous form occurs. • The amorphization process is triggered in the very early stages of dehydration. Abstract Colemanite is a natural borate that can be used as an aggregate in neutron-radiation shielding concretes. In this study, we report its thermal behavior, up to 500 °C, by describing: 1) its dehydration mechanisms and 2) its thermo-elastic parameters. The thermal expansion of colemanite is significantly anisotropic. The refined volume thermal expansion coefficient at ambient conditions is: α V 0 = 4.50(10)·10−5 K−1. The loss of structural H 2 O occurs at least from ∼240 °C, and at T > 325 °C an irreversible amorphization occurs, followed by a complete dehydration. The potential implications on the use of colemanite as concrete-aggregate are discussed. [ABSTRACT FROM AUTHOR]

In the frame of Generation IV reactors a renewed interest in pyro-processing of spent nuclear fuel is underway. Molten chloride salt waste arising from the recovering of uranium and plutonium through pyro-processing is one of the problematic wastes for direct application of vitrification or ceramization. In this work, Sodalite and SAP have been evaluated and compared as potential matrices for confinement of spent chloride salt waste coming from pyro-processing. To this aim Sodalite and SAP were synthesized both in pure form and mixed with different glass matrices, i.e. commercially available glass frit and borosilicate glass. The confining matrices were loaded with mixed chloride salts to study their retention capacities with respect to the elements of interest. The matrices were characterized and leached for contact times up to 150 days at room temperature and at 90 °C. SEM analyses were also performed in order to compare the matrix surface before and after leaching. Leaching results are discussed and compared in terms of normalized releases with similar results reported in literature. According to this comparative study the SAP matrix with glass frit binder resulted in the best matrix among the ones studied, with respect to retention capacities for both matrix and spent fuel elements. [ABSTRACT FROM AUTHOR]

Within the Partitioning and Transmutation strategies, great efforts have been devoted in the last decades to the development of lipophilic ligands able to co-extract trivalent Lanthanides (Ln) and Actinides (An) from spent nuclear fuel. Because of the harsh working conditions these ligands undergo, it is important to prove their chemical and radiolytic stability during the counter-current multi-stage extraction process. In the present work the hydrolytic and radiolytic resistance of the freshly prepared and aged organic solutions containing the new ligand (2,6-bis[(N-methyl-N-dodecyl)carboxamide]-4-methoxy-tetrahydro-pyran) were investigated in order to evaluate the impact on the safety and efficiency of the process. Liquid–liquid extraction tests with spiked solutions showed that the ligand extracting performances are strongly impaired by storing the samples at room temperature and in the light. Moreover, the extracting efficiency of the irradiated samples resulted to be influenced by gamma irradiation, while selectivity remains unchanged. Preliminary mass spectrometric data showed that degradation is mainly due to the acid-catalysed reaction of the ligand carboxamide and ether groups with the 1-octanol present in the diluent. [ABSTRACT FROM AUTHOR]

This work describes a metabolic profiling study of non-irradiated and irradiated beef (at 2.5, 4.5 and 8 kGy) using 1 H NMR and chemometrics. The assignment of all major NMR signals of the aqueous/methanolic extracts was performed. A comprehensive multivariate data analysis proved the ability to distinguish between the irradiated and non-irradiated beef. Classification trees revealed that three metabolites (glycerol, lactic acid esters and tyramine or a p -substituted phenolic compound) are important biomarkers for classification of the irradiated and non-irradiated beef samples. Overall, the achieved metabolomic results show that the changes in the metabolic profile of meat provide a valuable insight to be used in detecting irradiated beef. The use of the NMR-based approach simplifies sample preparation and decrease the time required for analysis, compared to available official analytical procedures. [ABSTRACT FROM AUTHOR]

Volatile compounds produced by irradiation in ground beef patties, packaged under vacuum, were extracted by head-space solid-phase micro-extraction and quantified by gas-chromatography coupled to mass-spectrometry. The study was carried out at levels of irradiation, ranging from 0.5 to 8 kGy. Among the 101 detected volatiles compounds, 25 resulted correlated with dose. On the basis of further measurements at 30 and 120 days after irradiation, the most stable compounds with time were identified. To estimate the dose just after irradiation, linear combinations of selections of possible dose markers were obtained via partial least squares regression. A further data analysis showed that it is possible to reconstruct both the irradiation dose and the time elapsed after irradiation from the ratio between the peak areas of some dose markers. The adopted experimental procedure combined with a proper data analysis may lead to dose or dose/age reconstruction in a rapid, simple and efficient way. [ABSTRACT FROM AUTHOR]

RE BaCo 2 O 5+ δ layered perovskite oxides ( RE = Rare Earth) are promising cathodes for IT-SOFCs. In this work, a simple co-precipitation synthesis in aqueous medium was applied to prepare LaBaCo 2 O 5+ δ (LBC) and YBaCo 2 O 5+ δ (YBC) cathodes. The chemical and electrochemical properties of both materials were characterized via XRD, SEM, TPO, TG–DTA, 4-probe conductivity measurement, and EIS tests on symmetric cells. The coprecipitation synthesis revealed a promising preparation route: the measured ASR values of both materials were well comparable with the literature ones. A kinetic investigation of the O 2 reduction process was performed on LBC (600–800 °C, 5–100% O 2 , v/v), whose results were analyzed with equivalent circuits. The main steps were identified (oxygen diffusion and charge transfer at high frequency, O 2 chemisorption at medium frequency), and their activation energy and reaction order were quantified. Aging tests (500 h time on stream, 500–800 °C) revealed quick deactivation for YBC and good stability for LBC. [ABSTRACT FROM AUTHOR]

Abstract: The combination of 1H NMR lipid profiling with multivariate analysis was applied to differentiate irradiated and non-irradiated beef. Two pattern recognition chemometric procedures, stepwise linear discriminant analysis (sLDA) and artificial neural networks (ANNs), provided a successful discrimination between the groups investigated. sLDA allowed the classification of 100% of the samples into irradiated or non-irradiated beef groups; the same result was obtained by ANNs using the 1kGy irradiation dose as discriminant value suggested by the network. Furthermore, sLDA allowed the classification of 81.9% of the beef samples according to the irradiation dose (0, 2.5, 4.5 and 8kGy). 1H NMR lipid profiling, coupled with multivariate analysis may be considered a suitable and promising screening tool for the rapid detection of irradiated meat in official control of food. [Copyright &y& Elsevier]

Abstract: A series of four compounds (LaMnO3, La0.70Sr0.30MnO3−δ, La0.80Sr0.20FeO3−δ and La0.75Sr0.25Cr0.50Mn0.50O3−δ) of interest as electrode materials in intermediate temperature solid oxide fuel cells have been prepared using a carbonate co-precipitation route in aqueous medium. LaMnO3, La0.70Sr0.30MnO3−δ, and La0.75Sr0.25Cr0.50Mn0.50O3−δ have been obtained as a pure phase, while La0.80Sr0.20FeO3−δ retained an impurity phase; fine microstructures with sub-micron sized particles can be obtained in all cases at the proper calcinations temperature, except for LaMnO3. The precipitation yield of the single metal ions have been experimentally determined in the mother liquors and in the final powders; the results have been evaluated also in comparison with expected yields calculated from thermodynamics of the precipitation process using the software Medusa. pH higher than 7.5 are suggested to avoid ion losses for all cations. Structural and microstructural properties and TPO/TPR behaviour suggest that materials prepared via co-precipitation, especially LSCM, could be suited as electrode materials in solid oxide fuel cells. [Copyright &y& Elsevier]

Abstract: An improved method for determination of 2-dodecylcylobutanone (DCB) in irradiated ground beef patties was developed. This method is based on a head-space solid-phase microextraction (HS-SPME) technique followed by gas-chromatography–mass-spectrometry (GC/MS) detection. SPME conditions were optimised: time and temperature for the adsorption of DCB on the polydimethylsiloxane (PDMS) fiber were set at 60min and 80°C, respectively. A matrix-matched standard calibration in the range 5–150ppb was carried out, using 2-pentylcyclopentanone as internal standard. Linearity (r 2 =0.9999), repeatability (8.4%), intermediate precision (13.6%), limit of detection (LOD) (1.5ppb), lower limit of quantification (LLOQ) (5ppb) demonstrated that the analytical procedure is fully reliable. The method was applied to irradiated samples in order to evaluate the dose–response effects. The concentration of DCB was quantified in beef patties irradiated at doses as low as 0.5kGy and was linearly increased up to 8kGy. [Copyright &y& Elsevier]

Abstract: Background: Hypercholesterolemia contributes to coronary heart disease but little is known about its direct effect on myocardial function. We evaluated left ventricular function using echocardiography and the effect of treatment with rosuvastatin in a group of patients with primary hypercholesterolemia. Methods and results: Thirty-three patients with primary hypercholesterolemia (HC) and without evidence of coronary heart disease and 25 aged matched healthy volunteers (C) were submitted to conventional echocardiography, pulsed wave tissue Doppler imaging (PWTDI), color Doppler myocardial imaging (CDMI) and integrated backscatter (IBS). Echocardiographic evaluation was repeated after 6 months of treatment with rosuvastatin (10mg/day) in 17 patients. Compared with C, patients with HC showed lower E/A ratio (p <0.0001) and higher Tei index mit (p <0.0001), as well as lower PW TDI E/A both at septum (p <0.0001) and at lateral level (p <0.0001) and higher modified Tei index both at septal annulus (p <0.0001) and lateral annulus (p <0.0001). Integrated backscatter parameters were significantly reduced in patients with HC (CVIsept p <0.0001 and CVI post wall p <0.05). CDMI derived indices in the two groups were not different. After 6 months of Rosuvastatin treatment a significant reduction of LDL cholesterol levels (51%, p <0.0001) was registered in HC patients together with a significant improvement of longitudinal global systolic and diastolic function (Tei index) and myocardial intrinsic contractility (CVI). Conclusions: These data suggest that in patients with hypercholesterolemia exists an early cardiomyopathy characterized by systolic and diastolic dysfunction. That could produce a substratum for an “impaired preconditioning”. Rosuvastatin seems able to revert systolic abnormalities. [Copyright &y& Elsevier]

Abstract: The effect of gamma irradiation in air is investigated on four thermoplastic polyesters (PET, PBT, PEN, PCT-co-ET) in films containing aromatic rings, in order to evaluate the influence of aromatic density and the role of oxygen on radiation resistance. Physical–chemical–nuclear analyses were used to this purpose. EPR measurements were carried out to detect radical stability against oxygen permeation. Viscometric investigations reported a very similar trend for all the investigated polyesters: a chain break effect that decreases at the highest doses. FT-IR analyses focused on the formation of oxidized species. Positron annihilation spectra pointed out a decrease of the intensity of ortho-positronium formation, while its lifetime remains unchanged with radiation dose. [Copyright &y& Elsevier]

The aim of this study was to determine whether early myocardial structural and functional systolic and diastolic alterations in asymptomatic and uncomplicated patients with type 1 diabetes mellitus (DM) could be detected using the new highly sensitive echocardiographic techniques of integrated backscatter and color Doppler myocardial imaging. Forty asymptomatic and uncomplicated patients with type 1 DM and 40 gender- and age-matched normal controls were studied. All patients were analyzed by conventional and new echocardiographic techniques (integrated backscatter and color Doppler myocardial imaging). Patients with DM showed reduced systolic function compared with controls, evidenced by significantly lower peak strain, strain rates, and cyclic variation indexes at the septum (p <0.0001, <0.01, and <0.001, respectively) and at the posterior wall level (p <0.0001, <0.0001, and <0.001, respectively). On receiver-operating characteristic curve analysis, systolic strain and the cyclic variation index showed the highest discriminating power for separating patients with DM and control subjects. Neither structural or ultrastructural nor diastolic functional abnormalities were detected. On univariate regression analysis, a significant inverse correlation was found for DM duration with conventional (E/A ratio) and unconventional (tissue Doppler imaging E/A ratio) indexes of diastolic function, in the absence of any correlation for systolic function. In conclusion, highly sensitive ultrasonic techniques demonstrate evidence of left ventricular systolic dysfunction in the early stage of type 1 DM, in the absence of ultrastructural and left ventricular diastolic functional abnormalities. [Copyright &y& Elsevier]

Accelerated coronary artery disease remains the limiting factor in the long-term survival of heart transplant (HT) recipients and occurs in approximately 50% of patients by 5 years after transplantation. Sequelae of graft arteriosclerosis include congestive heart failure (due to acute or chronic ischemia), graft loss, and death. Unfortunately, as a consequence of cardiac denervation, symptoms are often atypical or completely absent, and thus presentation with an acute coronary syndrome is extremely uncommon. We describe the case of an HT recipient with a typical clinical picture of an acute myocardial infarction (MI), who presented to our hospital 2 hours after the onset of symptoms and was successfully treated with primary percutaneous transluminal coronary angioplasty (PTCA). [Copyright &y& Elsevier]

Coronary artery anomalies (CAAs) are a rare angiographic finding, sometimes associated with acute coronary events. We report on a case of primary angioplasty for inferior acute myocardial infarction (AMI) in a 66-year-old woman with a solitary coronary ostium in the right Sinus of Valsalva and a “superdominant” right coronary artery. We also discuss two potential pitfalls of primary angioplasty: correct interpretation of coronary anatomy and approach to challenging lesions. [Copyright &y& Elsevier]

Purpose: Metabolic Syndrome as defined by ATP III criteria, a constellation of risk factors associated with insulin resistance, predisposes to premature atherosclerosis and early coronary events. Whether that negative risk profile is associated with endothelial dysfunction remains to be established. Materials and methods: Transcapillary escape rate of albumin (TERalb), a measure of capillary permeability and integrity of systemic capillary endothelium, and forearm vasodilation to intra-arterial acetylcholine (ACH), an index of nitric oxide (NO)-mediated vasomotor dysfunction, were assessed in 24 non-diabetic, uncomplicated hypertensive men with Metabolic Syndrome according to ATP III criteria (hypertension with at least two additional traits such as high triglycerides, low HDL, abdominal obesity, impaired fasting or post-load plasma glucose). Twelve age-matched lean normal hypertensive patients with normal lipid and glucose profile and nine normotensive subjects were the controls. All patients underwent lipids determination and fasting and post-OGTT insulin assessment; HOMA-IR was the index of insulin resistance. Results: TERalb was higher in hypertensive patients with Metabolic Syndrome, without differences between hypertensive and normotensive controls. Blood pressure (BP), lipids, plasma glucose, insulin levels and HOMA-IR were unrelated to TERalb. Responses to acetylcholine were selectively attenuated in metabolic patients and, on an individual basis, related only to HDL cholesterol levels, independent of LDL cholesterol, BP, body size, triglycerides, and HOMA-IR values. No relationship existed between responses to acetylcholine and TERalb. Conclusions: Altered systemic capillary permeability characterizes insulin-resistant hypertensive patients with Metabolic Syndrome. That defect, which may promote early atherosclerosis development, coexists with blunted endothelial-mediated vasodilation, indicating a pervasive abnormality of endothelial function. [Copyright &y& Elsevier]

The aim of this study was to assess the role of intravenous myocardial contrast echocardiography (IMCE) in the prediction of left ventricular (LV) remodeling in patients with acute myocardial infarction (AMI). Sixty-three patients with AMI, who were successfully treated with acute coronary angioplasty, underwent IMCE and low-dose dobutamine echocardiography during hospital admission. IMCE was graded semiquantitatively on a score of 0 (no visible contrast effect), 0.5 (patchy myocardial contrast enhancement), and 1 (homogenous contrast effect). Patients were considered to have microvascular impairment if <50% of segments within the infarct-related area had score of 1. A mean perfusion score index was calculated for each patient. Patients with a good perfusion at IMCE (IMCE+) showed a lower creatine kinase peak (p = 0.001) and lower creatine kinase-MB (p = 0.01), and a better baseline regional contractile function compared with patients who had negative results at IMCE (IMCE−) (p <0.0001) and a higher amount of myocardial viability at low-dose dobutamine echocardiography (p = 0.03). At follow-up, a higher improvement in regional systolic function (p = 0.0006) was observed in IMCE+ patients, whereas IMCE− patients showed an evident increase in LV end-diastolic volume from baseline to 6-month follow-up (p <0.0001), implying LV remodeling, which has been associated with a higher incidence of adverse cardiac events (p = 0.005). By stepwise multiple regression analysis, microvascular impairment at IMCE was a significant independent predictor of LV remodeling (p <0.0001). Thus, IMCE seems to be an important diagnostic tool, able to predict LV remodeling in patients with AMI. [Copyright &y& Elsevier]

Purpose: To compare different growth conditions for endothelial progenitor cells (EPCs) from peripheral blood mononuclear cells (PBMNCs). Methods and materials: PBMNCs of healthy volunteers were cultured on fibronectin as follows: M199 with VEGF, bFGF, IGF-I; the same medium with bovine retina-derived extract (RDE); freshly isolated or depleted of adherent cells PBMNCs in HUVEC conditioned medium; DiI-stained PBMNCs with HUVECs (1:4 ratio) in M199 with RDE. PBMNCs were analysed by FACS using mAbs for endothelial markers. EPCs migration was determined using a modified Boyden chamber assay and VEGF as chemoattractant. EPCs were seeded alone or with HUVECs on Matrigel to assess in vitro angiogenesis. Results: With growth factors, numerous cell clusters appeared within 1 week. Spindle-shaped and attached cells sprouted, differentiating in endothelial cell (EC)-like cells within 2 weeks and forming cobblestone-like monolayers within 3 weeks. With RDE, numerous large cell clusters appeared within 1 week, but the number of cells with an EC morphology decreased during culture. FACS confirmed the endothelial phenotype and attached cells were able to migrate in response to VEGF. When nonadherent cells were cultured in HUVEC conditioned medium, they proliferated readily and EDCs were induced while freshly isolated cells neither proliferated nor induced EPCs. FACS analysis of the cocultures showed the presence of double-labeled PBMNCs expressing endothelial antigens. Capillary-like structures were observed on Matrigel only from cocultures and PBMNCs were able to incorporate in these networks. Conclusions: PBMNCs are able to differentiate in EPCs when stimulated with appropriate culture conditions (growth factors, HUVEC conditioned medium, HUVECs). [Copyright &y& Elsevier]