Search

Graphical abstract Highlights • Simultaneous degradation of eight pharmaceuticals at μg L−1 using Fenton reaction was evaluated. • Two different iron addition strategies were evaluated to improve Fenton treatment at near neutral pH. • A purpose-built database that allowed monitoring 97 transformation products in a single injection was developed. • The purpose-built database was used to identified the most persistent transformation products. • Most transformation products generated were classified as of high toxicity and showed ready biodegradability. Abstract This work evaluates the Fenton process in the removal of eight pharmaceuticals (gemfibrozil, nimesulide, furosemide, paracetamol, propranolol, dipyrone, fluoxetine, and diazepam), present at an initial concentration of 500 μg L−1 for each compound, from three different water matrixes (distilled water, simulated wastewater, and hospital wastewater). The Fenton process conditions (iron and hydrogen peroxide concentrations, and pH) were optimized for the distilled water matrix by Doehlert design associated with response surface methodology. These corresponded to initial Fe2+ and hydrogen peroxide concentrations of 12.5 and 533 mg L−1, respectively, and pH 5.0. Mineralization rates and pharmaceutical degradation were monitored for all water matrixes and different experimental conditions employed. Unique iron addition, using low (12.5 mg L−1) and increased concentrations (37.5 mg L−1) were evaluated. These preliminary results motivated the study of the Fenton process employing successive iron additions and using an excess of hydrogen peroxide in the reaction medium. Multiple iron addition favored higher oxidation of the initial contaminants. Finally, the most persistent transformation products generated during the Fenton process were identified by liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UHPLC-QTOF MS) using a purpose-built database that allowed monitoring 97 transformation products in a single injection. In this study, 12 transformation products (TPs) were tentatively identified employing this purpose-built database. Most TPs generated were classified as of high toxicity (Cramer rules) and showed ready biodegradability (START biodegradability). [ABSTRACT FROM AUTHOR]

Plant ingredients and processed animal proteins are alternative feedstuffs for fish feeds in aquaculture. However, their use can introduce contaminants like pesticides that are not previously associated with marine Atlantic salmon and gilthead sea bream farming. This study covers the screening of around 800 pesticides by gas chromatography (GC) and liquid chromatography (LC) coupled to high resolution time-of-flight mass spectrometry in matrices throughout the entire marine food production chain. Prior to analysis of real-world samples, the screening methodology was validated for 252 pesticides to establish the screening detection limit. This was 0.01 mg kg −1 for 113 pesticides (45%), 0.05 mg kg −1 for 73 pesticides (29%) and >0.05 mg kg −1 for 66 pesticides (26%). After that, a quantitative methodology based on GC coupled to tandem mass spectrometry with atmospheric pressure chemical ionization source (GC-APCI-MS/MS) was optimized for the pesticides found in the screening. Although several polar pesticides, of which pirimiphos methyl and chlorpyriphos-methyl were most dominant, were found in plant material and feeds based on these ingredients, none of them were observed in fillets of Atlantic salmon and gilthead sea bream fed on these feeds. [ABSTRACT FROM AUTHOR]

Nowadays, there is an increasing concern over the presence of contaminants in the aquatic environment, where they can be introduced from wastewater after their incomplete removal in the treatment plants. In this work, degradation of selected emerging pollutants in the aqueous and solid phases of sewage sludge has been investigated after anaerobic digestion using two different digesters: mesophilic and thermophilic. Initially, sludge samples were screened by ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS) for identification of emerging contaminants in the samples. In a second step, a target quantitative method based on LC coupled to tandem MS was applied for selected pollutants identified in the previous screening. The behaviour of the compounds under anaerobic conditions was studied estimating the degradation efficiency and distribution of compounds between both sludge phases. Irbesartan and benzoylecgonine seemed to be notably degraded in both phases of the sludge. Venlafaxine showed a significant concentration decrease in the aqueous phase in parallel to an increase in the solid phase. The majority of the compounds showed an increase of their concentrations in both phases after the digestion. Concentrations in the solid phase were commonly higher than in the aqueous for most contaminants, indicating that they were preferentially adsorbed onto the solid particles. [ABSTRACT FROM AUTHOR]

In ARTEMIS, 58% of AR101-treated subjects vs. 2% of placebo-treated subjects tolerated 1000 mg peanut protein as a single dose at exit double-blind, placebo-controlled food challenge (DBPCFC; P < 0.0001) following treatment with AR101, an investigational oral biologic drug product for peanut oral immunotherapy. Immune responses to AR101 were assessed at 3 timepoints and compared with the placebo treatment group. All enrolled subjects had a clinical history of peanut allergy, demonstrated sensitization to peanut (skin prick test [SPT] mean wheal diameter ≥ 3 mm and/or peanut-specific immunoglobulin E [psIgE] ≥ 0.35 kUA/L), and reacted to ≤ 300 mg peanut protein at screening DBPCFC. SPT wheal diameter (mm), psIgE (kUA/L) and psIgG4 (mgA/L) assessments were performed at screening, end of dose escalation and study completion (following 3 months at 300 mg/day). Differences between treatment groups from screening to exit were analyzed using an ANCOVA model with terms fitted for group, country and screening value. A total of 175 ARTEMIS subjects (AR101 n = 132, placebo n = 43) were treated. SPT wheal diameter, psIgE levels, psIgG4 levels and psIgE/IgG4 ratio are summarized in Table 1. From baseline to exit (AR101 vs. placebo), psIgG4 levels increased (P < 0.0001); SPT wheal diameter (P < 0.0001) and psIgE/psIgG4 (P < 0.0001) decreased. In AR101-treated subjects, psIgE levels 2 increased at the end of dose escalation and decreased back to baseline levels, with no change between treatment groups (P = 0.6089) from baseline to exit. Exposure to AR101 was associated with immunologic changes consistent with immunomodulation: increased psIgG4, decreased peanut SPT wheal size and transient changes in psIgE levels, as reported in previous peanut oral immunotherapy trials. [ABSTRACT FROM AUTHOR]

Abstract: Many medical and biological problems require the analysis of large sequences of microscope images, these images capture phenomena of interest and it is essential to characterize their spatial and temporal properties. The purpose of this paper is to show a new statistical methodology for estimating these parameters of interest in image sequences obtained in the observation of endocytosis. Endocytosis is a process by which cells traffic molecules from the extracellular space into different intracellular compartments. These images are obtained using a very specialized microscopy technique called Total Internal Reflecting (TIRFM). The Homogeneous Temporal Boolean Model (HTBM) has been recently used to analyze these type of sequences of images. By using a HTBM, spatial homogeneity of events in the cell membrane must be assumed but this is an open question in the biological understanding of the endocytic process. Our aim in this paper is to generalize this methodology to overcome this drawback. In the methodological aspect this work has a threefold aim: to broaden the notion of HTBM by introducing the concept of Non-Homogeneous Temporal Boolean Model; to introduce a hypothesis testing procedure to check the spatial homogeneity assumption; and finally, to reformulate the existing methodology to work with underlying non-homogeneous point processes. We check the goodness of our methodology on a simulated data set and compare our results with those provided by visual inspection and by assuming spatial homogeneity. The accuracy of the results obtained with simulated data ensures the validity of our methodology. Finally we apply it, as an illustration, to three sequences of a particular type of endocytosis images. The spatial homogeneity test confirms that spatial homogeneity cannot be assumed. As a result, our methodology provides more accurate estimations for the duration of the events and, information about areas of the membrane with higher accumulation of them. [Copyright &y& Elsevier]

Abstract: An advanced solar unit is designed to match the needs of building integration and concentrating photovoltaic/thermal generation. The unit proposed accurately combines three elements: a domed linear Fresnel lens as primary concentrator, a compound parabolic reflector as secondary concentrator and a photovoltaic-thermal module. In this work the photovoltaic-thermal generator is built, analysed and characterized. Models for the electrical and thermal behaviour of the module are developed and validated experimentally. Applying a thermal resistances approach the results from both models are combined. Finally, efficiency electrical and thermal curves are derived from theoretical analysis showing good agreement with experimental measurements. [Copyright &y& Elsevier]

Abstract: Herein, we report efficient catalysts based on phosphoramidites for the asymmetric copper-catalyzed conjugate addition of Grignard reagents to acyclic α,β-unsaturated ketones. A variety of Grignard reagents can be added to aliphatic and aromatic acyclic enones with good yields and moderate to good enantioselectivities. [Copyright &y& Elsevier]

Abstract: (S)-2-[2-(p-Tolylsulfinyl)phenyl]acetaldehyde reacts with different O-silylated ketenethioacetals in the presence of Yb(OTf)3 yielding β-hydroxythioesters in high yields and diastereoselectivities. The obtained compounds were readily transformed into β-hydroxyacids and their corresponding diols. These Mukaiyama aldol reactions are a direct evidence of the ability of the sulfinyl group to control 1,5- and 1,6-asymmetric induction processes. [Copyright &y& Elsevier]

Abstract: A methodology to estimate PV electrical production from outdoor testing data is presented. It is based on the adjustment of a well known I–V model curve slightly modified and a new maximum power output expression. The method is developed to provide PV module performance parameters for all operating conditions encountered by typical photovoltaic systems. The method, theoretically based, is reasonably simple, yet accurately predicts operating conditions performance. The main advantage of the methodology developed is that it allows photovoltaic users to control the PV modules production based on measurements that can be performed far away from specialized photovoltaic reference laboratories even when standard testing conditions can not be achieved. [Copyright &y& Elsevier]

Abstract: Reactions of (2-p-tolylsulfinyl)benzyl alkyl (and aryl) ketones (δ-ketosulfoxides) with Et2AlCN in the presence of Yb(OTf)3 take place in a completely stereoselective manner, demonstrating the efficiency of the sulfinyl group in the control of the stereoselectivity of 1,5-asymmetric hydrocyanation processes as well as the ability of Yb(OTf)3 to form chelated species with ketosulfoxides. The behavior of their methyl derivatives at the benzylic position is dependent on the configuration at the chiral carbon. The resulting sulfinyl cyanohydrins were readily transformed into α-hydroxyamides by hydrolysis of the CN group and hydrogenolysis of the C–S bond. [Copyright &y& Elsevier]

Abstract: The efflux process due to p-glycoprotein-like mechanisms of ciprofloxacin (CIP) and grepafloxacin (GRX) has been studied “in situ” in rats and “in vitro” in Caco-2 cells. The results were modelled by a curve fitting procedure which allowed the characterization of the passive (P d) and carrier mediated parameters (V m and K m) from the raw data without initial velocities estimation. CIP absorption in rat was characterized as a passive diffusion at the assayed concentrations. Although the involvement of an efflux transporter cannot be ruled out, its relevance in the transport of the fluoroquinolone is negligible. In GRX absorption, an efflux process is implicated and it is detected in both absorption models. GRX permeability depends on the intestinal segment, reflecting the previously reported different expression level of the efflux transporters along the gut in rat. A first attempt to correlate the “in vitro” and the “in situ” data has been done. The mathematical model has been constructed using very simplistic assumptions and it will require further refinement but, nevertheless, the results are promising and demonstrate that a good modelling approach helps to identify the system critical parameters and how the system behaviour change when the parameters are modified as it happens when we move from the “in vitro” to the “in situ” level. Predicted versus experimental permeability values show a good correlation, demonstrating that the relevance of the secretion process “in situ” in rat can be predicted from the “in vitro” cell results. [Copyright &y& Elsevier]