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Heme, an iron-containing prosthetic group found in many proteins, carries out diverse biological functions such as electron transfer, oxygen storage and enzymatic reactions. Hemin, the oxidised form of heme, is used to treat porphyria and also to activate heme-oxygenase (HO) which catalyses the rate-limiting step in heme degradation. Our group has previously demonstrated that hemin displays antitumor activity in breast cancer (BC). The aim of this work has been to study the effect of hemin on protein expression modifications in a BC cell line to gain insight into the molecular mechanisms of hemin antitumor activity. For this purpose, we carried out proteome analysis by Mass Spectrometry (MS) which showed that 1309 proteins were significantly increased in hemin-treated cells, including HO-1 and the proteases that regulate HO-1 function, and 921 proteins were significantly decreased. Furthermore, the MS-data analysis showed that hemin regulates the expression of heme- and iron-related proteins, adhesion and cytoskeletal proteins, cancer signal transduction proteins and enzymes involved in lipid metabolism. By biochemical and cellular studies, we further corroborated the most relevant in-silico results. Altogether, these results show the multiple physiological effects that hemin treatment displays in BC and demonstrate its potential as anticancer agent. [ABSTRACT FROM AUTHOR]

The measured swelling pressures against tunnel linings range between a fraction of one MPa and 6–7 MPa. A strong spatial heterogeneity is often observed. The paper integrates these considerations into a procedure to design tunnel linings in anhydritic formations. Three-dimensional effects and proper consideration of heterogeneity is shown to be consistent with monitoring data of lining reinforcement stresses. The calculation methodology is illustrated in the case of the Lilla tunnel lining, which was monitored for more than 6 years. The described procedure leads to a rational design away from the conservatism of the assumption of uniform pressures against lining and two-dimensional modelling of tunnel cross-section. Highlights: The paper interprets internal lining stresses by means of a back-analysis which leads to a consistent characterization of spatial heterogeneity of swelling pressures A long stretch, one kilometre long, of heavily instrumented Lilla tunnel lining was interpreted as a gigantic transducer to perform the back-analysis Consistent modelling requires a three-dimensional representation of lining and swelling rock Despite high local swelling pressures, compressive circumferential stresses dominate lining behaviour, against anticipated design results Results and conclusions of the paper may lead to relevant economic savings in the design of linings in expansive anhydritic claystone [ABSTRACT FROM AUTHOR]

This study aims to provide anthracological data on forest transformations on the north-eastern Iberian Peninsula during the transition from the last glacial GS-2a to the last isotopic event of interstadial GI-1. We present a complete anthracological sequence from Molí del Salt (Vimbodí i Poblet, Tarragona, NE Iberian Peninsula), a site assigned to the Late Upper Palaeolithic. Our results suggest a continuous forest cover transformation throughout the inter-GI-1. Forest opening was determined by the retreat of Pinus sylvestris type, which was dominant during the Late Pleistocene, in relation to the continuous expansion of Juniperus sp. Likewise, our results suggest a progressive increase in the diversity of cold- and drought-resistant mesophilic taxa, which would have begun with the more temperate climatic conditions occasioned by the positive isotopic oscillations of GI-1. A comparison with other paleoecological data from the Iberian Peninsula suggests the presence of different biogeographic regions, as evidenced by different frequencies of certain montane and meso-thermophilic taxa. Our research also made use of a new methodology based on the spatial distribution of the charcoal remains recovered from Late Magdalenian layer A of Molí del Salt. The results have provided data with which to evaluate the taphonomic alterations identified in the charcoal fragments, such as hyperfragmentation and the occurrence of postdepositional processes. This analysis has increased the temporal resolution of the archaeological fieldwork, allowing us to identify unique events of human activity in a context of cumulative palimpsests. Finally, the Kernel distributions according to the standard deviation of the tree taxa, projected both in plan (X-Y) and in section (X-Z1), indicate human strategies in fuel selection that differentiated between Pinus sylvestris type, Juniperus sp. and Prunus sp. [ABSTRACT FROM AUTHOR]

In this research, a multiphase numerical simulation (steel-slag-argon) was carried out by coupling the VOF model with the transitory heat losses of the liquid steel during the injection of argon in the secondary refining process. To model the radiation in the free surface of the ladle, three models, P-1, discrete ordinates, and Rosseland, were considered. The thermal behavior of magnesia-carbon (MgO-C) and high alumina (Al2O3), which are commonly used in the industry, as a work wall was compared. Likewise, the behavior of two slag of different chemical composition was analyzed with two layer thicknesses. The results of the fluid dynamics agreed with those obtained in a physical scale model with the PIV technique. In addition, it was found that the Rosseland model allowed to quantify the radiative heat losses with a good approximation according to the results obtained in the industry. It was observed that the more viscous slag with greater thickness reduced the opening of the slag layer. Finally, the heat losses in the liquid steel could be controlled by manipulating the variables of thickness and viscosity of the slag and also the type of refractory of the ladle. [ABSTRACT FROM AUTHOR]

Abstract: The hydrolysis of cellulose into glucose is a critical step for the conversion of lignocellulosic biomass into fuels and chemical products. The combination of supercritical water hydrolysis in ultrafast reactors, with the subsequent hydrolysis of the cello-oligosaccharides on silver-exchanged mesoporous mordenite zeolite, offers the possibility of a clear enhancement in the conversion of cellulose and in glucose formation. Complete dissolution of cellulose is achieved in the supercritical step and 81.8% of formed oligosaccharides are hydrolyzed in the catalytic step, with a yield into glucose of 77.0%. A fraction of Al is octahedrally coordinated, indicating a distribution of acid sites after the silver exchange. A deactivation of the catalyst between the first and third reaction cycle is observed, with a reduction in hydrolyzed carbon from 81.8% up to 45.6%. However, the selectivity to glucose only varies from 94.1 to 81.8%. Afterwards, the activity remains constant up to the fifth cycle. The presence of Ag(0) particles, together with the formation of coke, are responsible for the partial blockage of the pores of the support and loss of catalytic activity.Graphical abstract: [ABSTRACT FROM AUTHOR]

The fluid dynamics of a straight tundish was studied when Ar-gas was fed through the bottom, using mathematical simulation. Flow rates of 15 and 40 liters/min of argon in three locations into the tundish - near input steel, center, and near output steel - were analyzed. A stochastic model was employed for determining statistically the particle amount (emulating alumina particles) in the inclusions removal. From these calculations and those of the Residence Time Distribution (RTD) curves, we found a direct relationship to improve steel quality. Specifically, removal of the smaller nonmetallic inclusions was significantly enhanced for cases with the lowest dead volume fraction; they correspond to those of the highest averaged residence time. Therefore, it was found that it is even possible to reduce argon consumption and still obtain good results of steel cleanness. [ABSTRACT FROM AUTHOR]

Objective To derive a risk score to predict in-hospital mortality for very old patients with decompensated chronic heart failure (DCHF). Methodology Retrospective cohort study that included patients ≥ 80 years admitted to a Geriatric Acute Care Unit with DCHF between January 2012 and December 2014. We analyzed 70 candidate risk factors and in-hospital mortality. We derived a risk model using multivariate logistic regression model and constructed a scale for scoring risk. We used bootstrapping techniques for the internal validation. Results We included 629 patients with mean age of 90 (SD5) years, 470 (73.1%) being women. Eighty-six (13.7%) patients died during the hospitalization. Factors included in the final risk model were NYHA class III-IV, severe functional dependence (Katz activities of daily living index < 2), infection as cause of exacerbation of heart failure, number of medications ≥ 8, albumin < 3 mg/dL, glomerular filtration rate < 60 mL/min, level of potassium in blood > 5.5 mEq/L and red blood cell distribution width (RDW) > 17%. In-hospital mortality in risk groups was 3.0, 4.6, 9.5, 15.1 and 36.3%, respectively. The area under ROC curve risk for score after bootstrapping was 0.77 (95%: CI 0.70-0.83). Conclusion This risk score could be useful for stratifying risk for in-hospital mortality among very old patients admitted to hospital for DCHF. [ABSTRACT FROM AUTHOR]

In this work, an analytical method for the determination of the 16 polycyclic aromatic hydrocarbons (PAHs), classified as priority pollutants by the US Environmental Protection Agency (EPA), on bitter orange leaves has been optimised and validated. The method has been applied to the evaluation of the applicability of leaves of bitter orange tree as a bioindicator of urban atmospheric pollution by these contaminants. Leaves of bitter orange trees were collected from 13 sampling points in Seville city (South of Spain). Sampling points were located in high-density traffic streets ( n = 5), in low-density traffic streets ( n = 5) and in urban parks ( n = 3). Fourteen of the 16 PAHs monitored were detected in bitter orange leaves. The highest mean concentrations corresponded to BaA, Phen, Pyr and Flt. The concentrations in high-density traffic streets were similar to those in low-density traffic streets. Lower concentrations were found in leaves from parks. PAH diagnostic ratios were applied to identify and to assess pollution emission sources. Diagnostic ratios obtained were consistent with traffic emissions as the main source of PAH to urban air. Based on the obtained results, leaves from bitter orange trees appears to be a promising inexpensive passive sampler suitable for extensive sampling in time and space that can be applied to evaluate risk assessment of urban population to PAH air pollution. [ABSTRACT FROM AUTHOR]

The arbitrary threshold of 5 × 10/L chronic lymphocytic leukemia (CLL)-like lymphocytes differentiates monoclonal B lymphocytosis (MBL) from CLL. There are no prospective studies that search for the optimal cut-off of monoclonal lymphocytes able to predict outcome and simultaneously analyze the prognostic value of classic, immunophenotypic, and cytogenetic variables in patients with asymptomatic clonal CLL lymphocytosis (ACL), which includes MBL plus Rai 0 CLL patients. From 2003 to 2010, 231 ACL patients were enrolled in this study. Patients with 11q deletion and atypical lymphocyte morphology at diagnosis had shorter progression-free survival (PFS) ( p = 0.007 and p = 0.015, respectively) and treatment-free survival (TFS) ( p = 0.009 and p = 0.017, respectively). Elevated beta-2 microglobulin (B2M) also correlated with worse TFS ( p = 0.002). The optimal threshold of monoclonal lymphocytes independently correlated with survival was 11 × 10/L ( p = 0.000 for PFS and p = 0.016 for TFS). As conclusion, monoclonal lymphocytosis higher than 11 × 10/L better identifies two subgroups of patients with different outcomes than the standard cut-off value of 5 × 10/L. Atypical lymphocyte morphology, 11q deletion and elevated B2M had a negative impact on the survival in ACL patients. [ABSTRACT FROM AUTHOR]

Liver transplantation is an effective and widely accepted therapy for children with end-stage liver disease. Major indications include primary liver disease, resulting in hepatic insufficiency, or severe morbidity secondary to chronic non-progressive liver disease and metabolic diseases of the liver. Liver replacement should not be considered if there is an acceptable alternative therapy. Relative contraindications to transplantation include irreversible impairment of other organ systems, major systemic infection and diseases expected to recur after transplantation. Early referral for pre-transplant evaluation is important to confirm the proper diagnosis and determine priority for transplantation, to identify potential contraindications, and to assist in supportive care of the patient with chronic liver disease. Innovations such as reduced-sized liver grafts and most recently, living related liver transplantation have increased the donor supply of organs for small infants and significantly reduced pre-transplant mortality. In addition, living donor transplantation allows infants to benefit from transplantation before developing severe complications of end-stage liver disease and reduces the incidence of primary graft non-function and rejection. Immunosuppression following transplantation is maintained with methylprednisolone, azathioprine and cyclosporine. Acute rejection is treated with short bursts of high-dose corticosteroids and when necessary OKT3. With this approach, 90% of the episodes of rejection can be successfully controlled. Survival after transplantation has steadily improved and survival rates of 70%-90% are routine. Following transplantation, children experience rapid nutritional restoration, increased muscle strength, marked progress in gross motor development and improved general health. [ABSTRACT FROM AUTHOR]

The occurrence of 16 pharmaceutical compounds in river sediments from Doñana National Park was investigated, as well as the ecotoxicological risk to the ecosystems of this well-known protected zone. Eight of the 16 pharmaceuticals were present in sediments. The highest concentrations in river sediments concern to diclofenac, salicylic acid and caffeine (52.1, 27.2 and 25.4 μg/kg dm). Naproxen, carbamazepine, propranolol, 17β-estradiol and estriol were the other pharmaceutical compounds detected in sediment samples. The relation between the concentration of these pharmaceutical compounds in sediments and river water in contact with was also investigated. While some compounds were detected exclusively in sediment samples (diclofenac, 17β-estradiol and estriol), others were detected only in surface waters in contact with (ibuprofen, ketoprofen and gemfibrozil). The outcome analyses of the ecotoxicological risk assessment showed that the presence of all studied pharmaceutical compounds involved a high toxicological risk at short and long term to Doñana ecosystem. [ABSTRACT FROM AUTHOR]

In the present work, the effectiveness of conventional wastewater treatments (activated sludge and oxidation ditches) and low-cost wastewater treatments (trickling filter beds, anaerobic lagooning and constructed wetlands) in the removal of pharmaceutically active compounds has been studied. To evaluate the efficiency of removal, 16 pharmaceutically active compounds belonging to seven therapeutic groups (anti-inflammatory drugs, antibiotics, antiepileptic drugs, β-blockers, nervous stimulants, estrogens and lipid regulators) have been monitored during 1-year period in influent and effluent wastewater from 11 wastewater treatment plants of Spain. Mean removal rates of pharmaceutically active compounds achieved in conventional wastewater treatments were slightly higher than those achieved in low-cost treatments, being 64% and 55%, respectively. Ibuprofen, naproxen, salicylic acid and caffeine were the pharmaceutical compounds most efficiently removed, regardless the wastewater treatment applied, with removal rates up to 99%. Anaerobic lagooning was the less effective treatment for the removal of the most persistent compounds: carbamazepine and propranolol. [ABSTRACT FROM AUTHOR]

Porosity variations in saline media containing humidity are induced by temperature gradients. A temperature imposed on a porous salt sample prepared with some brine and closed to mass transfer leads to significant variations of porosity in few weeks. Modelling of the experiments permits to understand the processes involved. [ABSTRACT FROM AUTHOR]

Mathematical simulations are employed to describe short- and large-scale flow distortions observed in a water model of a thin slab mold using a submerged entry nozzle (SEN) located at deep and shallow positions, operating at two casting speeds of 5 and 7 m/min. Two types of meniscus oscillations are identified; the first (high frequencies) has a relatively long life and short length scales, whereas the second (low frequencies) has a short life and its length scales are similar to those length scales in the mold. It was found, by turbulent flow principles, that the high-oscillation frequencies of the discharging jets are the same as those of the oscillating meniscus. Therefore, the discharging jets transfer vibrating momentum, with frequencies of 1.1 to 5 Hz, to the two upper roll flows during long periods of time, inducing those meniscus oscillations. The large-scale and short-life oscillations originate a dynamic distortion of the flow, forming deep meniscus depressions, especially for a casting speed of 7 m/min with the SEN in a shallow position. These dynamic distortions give origin to rotational flows in the lower boundaries of both jets, below the SEN tip, and even in the recirculatory eyes of the upper roll flows. The time scale of low-frequency oscillations agrees with the time scale of the production rate of kinetic energy along the jet’s length. Their origin is linked to a kinetic energy unbalance by the generation of a negative production rate. Because the flow must keep its energy budget, the fluid will transport, through mean convection and pressure–viscous mechanisms, further increases of momentum transfer during a short time, giving place to those dynamic distortions. Because of their large length scale, these dynamic and energetic distortions are the most dangerous to slab quality. [ABSTRACT FROM AUTHOR]

A water-physical model of a funnel-type thin slab mold fed by a two-port submerged entry nozzle (SEN) was employed to characterize the flow of liquid steel using dye tracer, particle image velocimetry, and video recording experiments. The overflow fluid flow pattern was the typical double-roll flow. A cyclic, low-frequency (≈0.01 s−1), and energetic flow distortion of a short-lived (8 to 12 seconds) inducing high meniscus oscillation was identified. Its intensity grew with high casting speeds (5 and 7 m/min) and with a shallow SEN immersion position (200 mm from the meniscus level to the SEN tip). This distortion originated from the apparent existence of vortex flows located below the two discharging jets, which are formed by shear stresses in their ends that act on the surrounding fluid. These vortexes exert momentum transfer upward through a cascade mechanism from the lowest part of the discharging jets until reaching the region close to the SEN tip. This cascade momentum transfer widens the separation of both jets, enhancing the fluid velocities of the upper rolls, which promotes a high-amplitude standing wave. It is inferred, based on the experimental results, that this flow distortion originated from an instantaneous unbalance of the turbulent kinetic energy in the discharging jets. The negative production of kinetic energy is ascribed as the source of this unbalance, which is compensated by a higher contribution of the turbulent kinetic energy through mean convection and turbulent transport mechanisms manifested through higher velocities. After the restoration of the energy balance, the system yields a stable meniscus to repeat the low-frequency cycle. [ABSTRACT FROM AUTHOR]

The people, places, economic and political influences of importance in the history of chemistry in Spain have been reviewed from the early XVIII century until today with particular reference to Analytical Chemistry. [ABSTRACT FROM AUTHOR]

Flux entrainment defects in a billet mold with two straight nozzles (outer radius of 60 mm, S60, and 73 mm, S73, and same interior radius of 36 mm) are studied using mathematical simulations and experimental techniques including particle image velocimetry (PIV), tracer injection, and water-oil modeling. Experimental findings indicated that using either of these nozzles at the deepest position of 135 mm (measured from the nozzle tip to the meniscus level) induces a flow near the meniscus, characterized by low turbulence yielding very stable water-oil interfaces. Simultaneously, owing to the mold radius, the entry jet induces a nonsymmetric flow downstream in the mold. At the shallow position of 90 mm, nozzle S73 induces a flow characterized by cyclic velocity spikes of low frequency and short duration close to the meniscus making the metal-flux interface highly instable. As the gap between the nozzle outer wall and the mold face is narrower and the nozzle position is shallower, the fluid close to the meniscus develops zones of high vorticity gradients leading to rotating flows, which are responsible for that instability. Water-oil experiments indicated that during the generation of this phenomenon, water flow entrains oil droplets in the side of the mold inner radius. Instability of metal-flux interface is then a consequence of the fluctuating nature of the recirculating flows in the mold, which induce upper rotating flows with large vorticity gradients. This mechanism explains actual flux entrainment defects in a billet caster. [ABSTRACT FROM AUTHOR]

Some of the major advances in the field of mining in the last three decades have referred to the development of new design and planning techniques for optimizing open-pit mining and the inclusion of a stochastic perspective in economic models that is more revealing than a purely deterministic perspective. These advances include the use of parametric techniques in the design and planning process, the formulation of criteria for establishing an optimum cut-off grade policy when the economic goal is to optimize net present value (NPV), and the introduction of economic risk analysis. This paper examines some of the difficulties involved in applying these techniques—arising largely as a result of a lack of knowledge of the spatial location and distribution of the deposit grades—and analyses how these difficulties can be tackled with the help of geostatistical simulation techniques that take probabilistic criteria into consideration during the optimization process. These techniques enable equally likely representations of the deposit to be obtained that reproduce the main dispersion features for the starting experimental data (covariance or variogram, as well as the histogram). Consequently, the uncertainty in regard to the deposit as well as its influence on the economic assessment of the deposit in risk terms can be evaluated. This paper also describes a simple method for introducing price and cost increases into the risk analysis via the Monte Carlo method and shows how geological, technical and economic uncertainty can be integrated in risk analyses. Although it is true that the relationship between prices and costs is maintained constant in mining planning based on using parametric techniques, it is no less true that the risk analysis requires the use of models in which the main parameters with a bearing on deposit economics are considered as stochastic variables. The proposed methodology simplifies the calculations and easily integrates the different sources of uncertainty. [ABSTRACT FROM AUTHOR]

We introduced the observations and researches using a Satellite Laser Ranging (SLR) system with high precision, which was designed and made in China and installed in the Observatory of San Juan University, Argentina, the capability of the system and the achievement of the cooperative procedure between China and Argentina. The SLR station in San Juan, set up by China and Argentina, is quite significant for improving the distribution of SLR stations and enhancing the orbital coverage of the whole earth. Since the SLR system started to work in the Observatory of San Juan University in the beginning of 2006, the operation is rather good, and rich data with high precision have been obtained. Further plan of the cooperation for the near future is also presented. [ABSTRACT FROM AUTHOR]

In this work, a new chelating resin [1,5- bis (2-pyridyl)-3-sulphophenyl methylene] thiocarbonohydrazide immobilised on aminopropyl-controlled pore glass (550 Å; PSTH-cpg) was synthesised and packed in a microcolumn which replaced the sample tip of the autosampler arm. The system was applied to the preconcentration of lead. When microliters of 10% HNO3, which acts as elution agent, pass through the microcolumn, the preconcentrated Pb(II) is eluted and directly deposited in a tungsten-rhodium coated graphite tube. With the use of the separation and preconcentration step and the permanent modifiers, the analytical characteristics of the technique were improved. The proposed method has a linear calibration range from 0.012 to 10 ng ml−1 of lead. At a sample frequency of 36 h−1 with a 90 s preconcentration time, the enrichment factor was 20.5, the detection and determination limits were 0.012 and 0.14 ng ml−1, respectively and the precision, expressed as relative standard deviation, was 3.2% (at 1 ng ml−1). Results from the determination of Pb in biological certified reference materials were in agreement with the certified values. Seawaters and other biological samples were analysed too. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

LDL phenotype B is a component of diabetic dyslipidaemia, but its diagnosis is cumbersome. Our aim was to find easily available markers of phenotype B in a group of type 2 diabetic subjects. We studied 123 type 2 diabetic patients (67.5% male, aged 59.3±10.1 years, mean HbA1c 7.4%). Clinical features and fasting total cholesterol, triglyceride, HDL cholesterol, LDL cholesterol (LDLc, using Friedewald's equation and an alternative formula), apolipoprotein B (apoB), lipoprotein (a) and LDL particle size (on gradient polyacrylamide gel electrophoresis) were assessed. Patients with phenotypes A (predominant LDL size ≥25.5 nm) and B (<25.5 nm) were compared, and regression analysis was performed to find the best markers of LDL particle. Cut-off points were obtained and evaluated as predictors of phenotype B (kappa index). Patients with phenotype B (36%) showed higher total cholesterol, triglyceride and apolipoprotein B, and lower HDL cholesterol and LDLc/apoB ratio. Triglyceride was the best predictor of LDL particle size (r=−0.632, p<0.01), but an LDLc/apoB ratio below 1.297 mmol/g detected phenotype B best (sensitivity 65.9%, specificity 92.4%, kappa=0.611). Although triglyceride concentration is the best predictor of LDL size in type 2 diabetes, LDLcholesterol/apolipoproteinB ratio is the best tool to detect phenotype B. [ABSTRACT FROM AUTHOR]

A new European Union legislation on sludge treatment is being introduced that will replace the one currently in force. The control of heavy metals is an important aspect of this new legislation. The most common methodology to examine the metal content of sludges is determination of total metal content after total or pseudo total digestion of the sludge samples. Nevertheless, this kind of analysis is not informative on the availability or mobility of the metals; a metal speciation analysis is therefore required. In this study, sludge samples from conventional activated sludge wastewater treatment plants (WWTP) were collected at different stages of an anaerobic sludge treatment process. In these samples, the total metal content and the distribution of metal species were determined (Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Ti, Zn) following a protocol of sequential extraction. Only 14% of the metal was present in readily available forms in the treated sludges. In composted sludges, this value dropped to 6%. [ABSTRACT FROM AUTHOR]

Traditionally, the Guadiamar River Basin (Seville, Southwest Spain) has received pollution from two different sources. In its upper course, from a pyrite exploitation and, in its lower reaches, from untreated urban and industrial wastes as well as wastes from intensive agricultural activity. In 1998, the accidental release in the river of about 6 million m3 of acid water and sludge from mine tailings contributed to worsen the pollution of an already contaminated area. The main polluting agents of the spill were heavy metals. It affected a large number of wells either directly or as a consequence of infiltration from polluted soils. Assessment of the pollution by total metal determination does not reveal the true environmental impact of the spill and speciation studies showing the distribution of the main pollutants are required. There is a direct association between the physicochemical speciation of an element and its bioavailability, toxicity and mobility. This article describes a distribution study of the metals Zn, Cd, Pb and Cu by speciation analysis of groundwater in six wells of the Guadiamar River Basin; the samples were taken several weeks after the spill. The speciation analysis resulted in the definition of three species categories: a) labile metal (H+ exchangeable), b) metal strongly associated to dissolved organic matter and c) metal associated with suspended material. Analysis was carried out by anodic stripping voltammetry (ASV). Metal speciation in groundwater of the Guadiamar River Basin allows a differentiation between: on the one hand, metals from the mining spill, and on the other hand a less recent pollution from accumulated infiltration of either mining or agricultural origin, the last one due to an abuse of phytosanitary products. [ABSTRACT FROM AUTHOR]

The V-T/R relaxation time of CDF was measured studying the laser-induced infrared fluorescence emitted by vibrationally excited CDF. Following excitation by the 10 R(12) line of a TEA CO laser infrared fluorescence has been detected without spectral resolution in the 1100-700 cm range. A decay rate of 28.8 ms Torr was obtained for pure CDF when it is excited with a fluence of 390 mJ/cm. Measurements have also been made in the presence of different bath gases (He, Ne, Ar, Xe, and CHF). [ABSTRACT FROM AUTHOR]

Energy absorption by CDF for different energy fluences from an intense TEA CO laser is reported as function of the pressure of CDF and various bath gases (He, Ne, Ar, Xe, and CHF). Collisional behavior at different conditions is discussed. [ABSTRACT FROM AUTHOR]

Energy absorption by CFCl from an intense TEA CO laser pulse is measured as a function of the pressure of CFCl and the pressure of Ar bath gas for different laser energy fluences. The fraction of the molecules excited by the laser field and the average energy of the molecular ensemble are determined by a simple experimental method. [ABSTRACT FROM AUTHOR]

Canaline and gabaculine, inhibitors of γ-aminotransferases and thus of ornithine aminotransferase (E.C. 2.6.1.13), decreased the flow through ornithine carbamoyl transferase (E.C. 2.1.3.3) in isolated rat hepatocytes incubated with 10 mM NHCl and ornithine. The levels of acetylglutamate, an essential activator of carbamoyl phosphate synthetase (ammonia) (E.C. 6.3.4.16), were also decreased, suggesting that the inhibitors had also caused a decrease in the rate of carbamoyl phosphate synthesis. Under these conditions, ornithine appears to be a precursor of acetylglutamate, via ornithine aminotransferase, possibly as a consequence of glutamate synthesis. The influence of aminooxyacetate, an aminotransferase inhibitor, has also been examined. [ABSTRACT FROM AUTHOR]

We present a theoretical-numerical investigation of porosity variations induced by temperature gradients in unsaturated saline media. It is known that temperature variations cause humidity variations which lead to liquid flow towards and vapour flow away from the hot source. When this phenomenon occurs in saline media, the liquid is salt saturated brine, so that evaporation causes salt precipitation and an ensuing porosity reduction. Condensation of water causes salt dissolution and porosity increase. This process may be important in the case of heat generating waste because it suggests that selfsealing may take place near the waste. On the other hand, salt mass balance will lead to porosity increases in other zones. [ABSTRACT FROM AUTHOR]

We propose a general formulation for nonisothermal multiphase flow of brine and gas through saline media. The balance equations include mass balance (three species), equilibrium of stresses and energy balance (total internal energy). Salt, water and air mass balance equations are established. The balance of salt allows the establishment of the equation for porosity evolution due to solid skeleton deformation, dissolution/precipitation of salt and migration of brine inclusions. Water and air mass balance equations are also obtained. Two equations are required for water: total water in the medium and water present in solid phase brine inclusions. The mechanical problem is formulated through the equation of stress equilibrium. Finally, the balance of internal energy is established assuming thermal equilibrium between phases. Some general aspects of the constitutive theory are also presented. [ABSTRACT FROM AUTHOR]

The nucleotide sequence of the coat protein genes and 3′ non-coding regions of two different resistance-breaking tobamoviruses in pepper have been determined. The deduced coat protein of an Italian isolate of pepper mild mottle virus (PMMV-I) consists of 156 amino acids and its 3′ non-coding region is 198 nucleotides long. They have been found to be very similar in sequence and structure to those previously reported for a Spanish isolate (PMMV-S). In contrast, a Dutch isolate termed P 11 codes for a coat protein of 160 amino acids and its 3′ non-coding region is 291 nucleotides long, which may have arisen by duplication. The nucleotide and the predicted coat protein amino acid sequence analysis show that this isolate should be considered as a new virus within the tobamovirus group. The term paprika mild mottle virus (PaMMV) is proposed. [ABSTRACT FROM AUTHOR]

The determination of nickel by ETA-AAS and ICP-AES in biological samples with prior extraction into methyl isobutyl ketone with 1,5-bis(di-2-pyridylmethylene) thiocarbonohydrazide as extracting reagent is described. Microwave dissolution in closed teflon vessels has been used for the dissolution of biological materials. At least three samples can be decomposed simultaneously with a preset heating programme. Results of analyses of some certified biological reference materials are given. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the development and application of a hybrid molecular dynamics/kinetic Monte Carlo simulation to model defect production and microstructure evolution in irradiated fcc metals. The molecular dynamics results show that the primary damage state produced by high-energy 30 keV recoils in low melting point, high-Z fcc metals such as Pb and Au is dominated by populations of large vacancy and interstitial clusters, and only a small percentage of the damage is produced as isolated point defects. Kinetic Monte Carlo simulations were used to calculate the fraction of the defects produced by the 30 keV recoils that are able to avoid recombination within their nascent cascade and freely migrate through the lattice. We show that because of in-cascade clustering this fraction is different for vacancies and interstitials and depends strongly on temperature. The results are used to provide a qualitative explanation for the experimentally observed differences in void swelling between fcc and bcc metals. The kinetic Monte Carlo simulations were also used to model damage accumulation in Pb under 30 keV self-recoil irradiation as a function of dose rate and temperature. [ABSTRACT FROM AUTHOR]