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The sorption isotherms of chitosan-glycerol films and of pure chitosan films using the static gravimetric method were performed. The experimental data were adjusted by several sorption models, and the GAB equation was the one that best represented the experimental data, being chosen to predict the adsorption and desorption behaviors of the films for the ranges studied of water activity (0.043–0.888) and of temperatures (20–50 °C). The chitosan-glycerol films presented higher values of monolayer moisture and lower heat involved in the monolayer compared to the pure chitosan films. The values of net isosteric heat and of differential entropy for the films increased exponentially with the moisture content decrease. Dry films with moisture content ( X e ) lower than 0.10 kg kg −1 (dry basis) presented morphological changes according to the isosteric heat and entropy curves, indicating water sorption more easily and the more amorphous material (crystallinity of 9%). While dry films at X e = 0.40 kg kg −1 (dry basis) maintained the characteristic of semicrystalline material (crystallinity of 33%). The enthalpy–entropy compensation showed that the process was controlled by the enthalpy and, it was only spontaneous for the samples in adsorption. The films were classified as a micro and mesoporous materials, and the average pores sizes were from 0.6 to 17 nm for desorption and, from 0.7 to 21 nm for adsorption. [ABSTRACT FROM AUTHOR]

Chemotherapy-Induced Peripheral Neuropathy (CIPN) is the most frequent adverse effect of pharmacological cancer treatments. The occurrence of neuropathy prevents the administration of fully-effective drug regimen, affects negatively the quality of life of patients, and may lead to therapy discontinuation. CIPN is currently treated with anticonvulsants, antidepressants, opioids and non-opioid analgesics, all of which are flawed by insufficient anti-hyperalgesic efficacy or addictive potential. Understandably, developing new drugs targeting CIPN-specific pathogenic mechanisms would dramatically improve efficacy and tolerability of anti-neuropathic therapies. Neuropathies are associated to aberrant excitability of DRG neurons due to the alteration in the expression or function of a variety of ion channels. In this regard, Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels are overexpressed in inflammatory and neuropathic pain states, and HCN blockers have been shown to reduce neuronal excitability and to ameliorate painful states in animal models. However, HCN channels are critical in cardiac action potential, and HCN blockers used so far in pre-clinical models do not discriminate between cardiac and non-cardiac HCN isoforms. In this work, we show an HCN current gain of function in DRG neurons from oxaliplatin-treated rats. Biochemically, we observed a downregulation of HCN2 expression and an upregulation of the HCN regulatory beta-subunit MirP1. Finally, we report the efficacy of the selective HCN1 inhibitor MEL57A in reducing hyperalgesia and allodynia in oxaliplatin-treated rats without cardiac effects. In conclusion, this study strengthens the evidence for a disease-specific role of HCN1 in CIPN, and proposes HCN1-selective inhibitors as new-generation pain medications with the desired efficacy and safety profile. [ABSTRACT FROM AUTHOR]

Building-Integrated Concentrated Photovoltaics (BICPV) is based on Photovoltaic (PV) technology which experience a loss in their electrical efficiency with an increase in temperature that may also lead to their permanent degradation over time. With a global PV installed capacity of 303 GW, a nominal 10 °C decrease in their average temperature could theoretically lead to 15 GW increase in electricity production worldwide. Currently, there is a gap in the research knowledge concerning the effectiveness of the available passive thermal regulation techniques for BICPV, both individually and working in tandem. This paper presents a novel combined passive cooling solution for BICPV incorporating micro-fins, Phase Change Material (PCM) and Nanomaterial Enhanced PCM (n-PCM). This work was undertaken with the aim to assess the unreported to date benefits of introducing these solutions into BICPV systems and to quantify their individual as well as combined effectiveness. The thermal performance of an un-finned metallic plate was first compared to a micro-finned plate under naturally convective conditions and then compared with applied PCM and n-PCM. A designed and fabricated, scaled-down thermal system was attached to the electrical heaters to mimic the temperature profile of the BICPV. The results showed that the average temperature in the centre of the system was reduced by 10.7 °C using micro-fins with PCM and 12.5 °C using micro-fins with n-PCM as compared to using the micro-fins only. Similarly, the effect of using PCM and n-PCM with the un-finned surface demonstrated a temperature reduction of 9.6 °C and 11.2 °C respectively as compared to the case of natural convection. Further, the innovative 3-D printed PCM containment, with no joined or screwed parts, showed significant improvements in leakage control. The important thermophysical properties of the PCM and the n-PCM were analysed and compared using a Differential Scanning Calorimeter. This research can contribute to bridging the existing gaps in research and development of thermal regulation of BICPV and it is envisaged that the realised incremental improvement can be a potential solution to (a) their performance improvement and (b) longer life, thereby contributing to the environmental benefits. [ABSTRACT FROM AUTHOR]

The present paper deals with the application of the potentiometric E-tongue system for water toxicity estimation in terms of qualitative and quantitative cyanobacterial microcystin toxins (MCs) detection. The data obtained by potentiometric multisensor system were correlated to the MCs content detected by standard cromatographic tecnique UHPLC-DAD, as far as by colorimetric enzimatic approach. The prediction of Microcystine-LR released by toxic Microcystis aeruginosa strains was possible with mean relative error of validation of 0.164 μg/l using PLS regression. Moreover, the possibility to distinguish toxic and non toxic Microcystis aeruginosa strains in potable water by means of E-tongue was demonstrated. [ABSTRACT FROM AUTHOR]

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Abstract: Brain is susceptible to oxidative stress and it is associated with age-related brain dysfunction. Previously, we have pointed out a dramatic decrease of glutathione levels in the rat brain after acetaminophen (APAP) oral administration overdose. Silymarin (SM) is a mixture of bioactive flavonolignans isolated from Silybum marianum (L.) Gaertn., employed usually in the treatment of alcoholic liver disease and as anti-hepatotoxic agent in humans. In this study, we have evaluated the effect of SM on enzymatic and non enzymatic antioxidant defensive systems in rat brain after APAP-induced damage. Male albino Wistar rats were treated with SM (200mg/kg/die orally) for three days, or with APAP single oral administration (3g/kg) or with SM (200mg/kg/die orally) for 3 days and APAP single oral administration (3g/kg) at third day. Successively the following parameters were measured: reduced and oxidized glutathione (GSH and GSSG), ascorbic acid (AA), enzymatic activity variations of superoxide dismutase (SOD) and malondialdehyde levels (MDA). Our results showed a significant decrease of GSH levels, AA levels and SOD activity and an increase of MDA and GSSG levels after APAP administration. After SM administration GSH and AA significantly increase and SOD activity was significantly enhanced. In the SM+APAP group, GSH values significantly increase and the others parameters remained unchanged respect to control values. These results suggest that SM may to protect the SNC by oxidative damage for its ability to prevent lipid peroxidation and replenishing the GSH levels. [Copyright &y& Elsevier]

Abstract: A novel analytical immunosensor array, based on a microtiter plate coupled to a multichannel electrochemical detection (MED) system using the intermittent pulse amperometry (IPA) technique, is proposed for the detection of aflatoxin B1 (AFB1). In the present work, the electrochemical behaviour and electroanalytical performance of the thick-film carbon sensors (also designated as screen-printed electrodes) incorporated in the multichannel electrochemical plate were first evaluated. Then the 96-well screen-printed microplate was modified in accord with a competitive indirect enzyme-linked immunoassay (ELISA) format for aflatoxin B1 detection. The measurements were performed using both spectrophotometric and electrochemical procedures and the results of the calibration curves, detection limit (LOD), sensitivity and reproducibility of the respective assay systems were evaluated. The immunoassay was then applied for analysis of corn samples spiked with AFB1 before and after the extraction treatment, in order to study the extraction efficiency and the matrix effect, respectively. These studies have shown that using this system, AFB1 can be measured at a level of 30pg/mL and with a working range between 0.05 and 2ng/mL. Good recoveries (103±8%) were obtained, demonstrating the suitability of the proposed assay for accurate determination of the AFB1 concentration in corn samples. The specificity of the assay was assessed by studying the cross-reactivity of PAb relative to AFB1. The results indicated that the PAb could readily distinguish AFB1 from other aflatoxins, with the exception for AFG1. [Copyright &y& Elsevier]

• A method for optimising cleaning schedules in photovoltaic systems is developed. • It minimises the levelised cost of energy and is applied to central Mexico. • Residential and commercial systems should be cleaned once per year in the region. • Utility-scale systems can be cleaned each 12–31 days as a function of cleaning costs. • A comparative analysis to other existing methods for the same case study is done. In this paper, the soiling impact on photovoltaic systems in Aguascalientes, in central Mexico, an area where 1.4GWp of new photovoltaic capacity is being installed, is characterised experimentally. A soiling rate of −0.16%/day in the dry season for optimally tilted crystalline silicon modules, and a stabilization of the soiling losses at 11.2% after 70 days of exposure were observed. With these data, a first of its kind novel method for determining optimum cleaning schedules is proposed based on minimising the levelised cost of energy. The method has the advantages compared to other existing methods of considering the system investment cost in the determination of the optimum cleaning schedule. Also, it does not depend on economic revenue data, which are often subject to uncertainty. The results show that residential and commercial systems should be cleaned once per year in Aguascalientes. On the other hand, cleaning intervals from 12 to 31 days in the dry season were estimated for utility-scale systems, due to the dramatic decrease of cleaning costs per unit photovoltaic capacity. We also present a comparative analysis of the existing criteria for optimising cleaning schedules applied to the same case study. The different methods give similar cleaning intervals for utility-scale systems and, thus, the choice of a suitable method depends on the availability of information. [ABSTRACT FROM AUTHOR]

Abstract: A highly sensitive method for the determination of aflatoxin M1 (AFM1) is described that involves the use of a disposable multichannel microplate coupled to intermittent pulse amperometry (IPA) for immunosensor development based on a direct competitive assay. Immunoassay parameters were evaluated and optimized to establish an electrochemical enzyme-linked immunosorbent assay (ELISA) procedure for AFM1 in milk samples. The suitability of the immunosensors for the direct analysis of the toxin in milk was assessed. AFM1 was measured with a working range of 5–250 pg mL−1 and a detection limit of 1 pg mL−1. Good recovery values (90–105%) were obtained. The method was used to study the recovery of this toxin in frozen (−30 °C) or lyophilized (4 °C) milk samples stored for up to 3 months. A significant, but variable, decrease (>50%) of the measured AFM1 concentration with respect to the initial toxin contamination levels was found. [Copyright &y& Elsevier]

Abstract: The aim of the present work was the development of an ELIME-array to achieve simple and rapid detection of AFB1 in corn samples. The system is based on an indirect competitive ELISA format using magnetic beads as immobilisation support and eight magnetised screen-printed electrodes as electrochemical transducers. After an optimisation study, a corn sample treatment, employing an extraction in acetonitrile/water followed by a clean-up step and solvent evaporation, was selected. For the construction of the calibration curve, which was used to evaluate both evaluation of the matrix effect on the performances of the ELIME-array and for the analysis of Certified Reference Materials (CRMs), standard solutions of AFB1 were added to blank dried corn extracts reconstituted in PBS. The detection limit and the sensitivity of the assay were calculated to be 0.6ngmL−1 and 1.5ngmL−1, respectively. Precision (11–26%) and recovery (95–114%) data of the ELIME-array, determined by analysing four CRMs, have shown that the proposed system appears suitable as a screening tool for the analysis of AFB1 in corn samples. [Copyright &y& Elsevier]

The quantitative evaluation of chemical elements from X-ray Fluorescence (XRF) analysis still remains a strong hurdle in X-ray Spectrometry, mainly due to significant matrix effects involved in the processes. The Fundamental Parameter Method (FPM) is a valid tool for the calculation of analyte concentration unless the primary source comes from a Synchrotron Radiation facility or the experimental design is based on a confocal layout. The approximation of an infinitely thin sample represents a feasible way to apply the FPM approach along with dedicated X-ray optics implemented in the XRF apparatus to improve the performance of the primary beam (and also of the fluorescence signal reaching the detector). This is routinely available at the XLab Frascati of INFN-LNF thanks to the "Rainbow X-ray" (RXR) facility, the μ XRF station opened to users and optimized for most of X-ray analytical research fields. The basic principle of the station is in the use of various geometrical combinations of polycapillary optics for X-ray beam shaping (focusing/collimation) applied to specially designed laboratory units. The flexible RXR layout allows investigating specimens of the dimensions ranging from several millimeters up to half meter and weighting up to several tens of kilograms with the main advantage of having a detection system able to work separately both at high and low X-ray energies. The aim of the present work is to show the results obtained in quantitative XRF analysis by applying the FPM approach to the RXR experimental layout in a study of the pigments covering two different Japanese scrolls, n.142 838 (also known as Engi Jizo Emakimono) and n. 142 846, coming from the private Ragusa Collection presently stored at Pigorini Museum in Italy. • Layout with x-ray tube and polyCO demonstrated for Cultural Heritage. • Application of FPM to μXRF studies is a valid tool for quantitative XRF. • Use of approximation of "thin" samples resulted successful in pigments study. • XRF results confirmed pigments formulation given by historical data. [ABSTRACT FROM AUTHOR]