Ab Initio Study of the Interaction of a Graphene Surface Decorated with a Metal-Doped C30 with Carbon Monoxide,Carbon Dioxide,Methane, and Ozone

Using DFT simulations, we studied the interaction of a semifullerene C₃₀ and a defected graphene layer. We obtained the C₃₀ chemisorbs on the surface. We also found the adsorbed C₃₀ chemisorbs, Li, Ti, or Pt, on its concave part. Thus, the resulting system (C₃₀-graphene) is a graphene layer decorated with a metal-doped C₃₀. The adsorption of the molecules depends on the shape of the base of the semifullerene and the dopant metal. The CO molecule adsorbed without dissociation in all cases. When the bottom is a pentagon, the adsorption occurs only with Ti as the dopant. It also adsorbs for a hexagon as the bottom with Pt as the dopant. The carbon dioxide molecule adsorbs in the two cases of base shape but only when lithium is the dopant. The adsorption occurs without dissociation. The ozone molecule adsorbs on both surfaces. When Ti or Pt are dopants, we found that the O₃ molecule always dissociates into an oxygen molecule and an oxygen atom. When Li is the dopant, the O₃ molecule adsorbs without dissociation. Methane did not adsorb in any case. Calculating the recovery time at 300 K, we found that the system may be a sensor in several instances.     

Effect of UV–Vis Irradiation on Enzymatic Activities and Physicochemical Properties of Four Grape Musts from Different Varieties

The influence of ultraviolet–visible irradiation on some quality attributes (pH, soluble solids content, color parameters, absorption spectrum, vitamin C, total acidity, total phenolics, formol index, and total and reducing sugars) and polyphenol oxidase, peroxidase, and pectinmethylesterase activities of fresh grape juices was investigated. Grape juice was made from two varieties of white grapes (Victoria and Dauphine) and two varieties of pink grapes (Emperor and Red Globe). Each juice was irradiated for 140 min with a high-pressure mercury lamp of 400 W that emits in a range between 250 and 740 nm. Polyphenol oxidase was not completely inactivated during irradiation, reducing only 80% of its initial activity in juices from white grapes and only 50% in those from pink grapes. On the contrary, peroxidase was completely inactivated. A slight or nonexistent variation was observed in most of the measured physicochemical parameters, showing high stability during irradiation. Only vitamin C and color had a significant variation, with an average decrease of 30% for vitamin C in all varieties and a more important variation of color parameters in the pink varieties than in the white ones.     

Occurrence of a new generation of disinfection byproducts

A survey of disinfection byproduct (DBP) occurrence in the United States was conducted at 12 drinking water treatment plants. In addition to currently regulated DBPs, more than 50 DBPs that rated a high priority for potential toxicity were studied. These priority DBPs included iodinated trihalomethanes (THMs), other halomethanes, a nonregulated haloacid, haloacetonitriles, haloketones, halonitromethanes, haloaldehydes, halogenated furanones, haloamides, and nonhalogenated carbonyls. The purpose of this study was to obtain quantitative occurrence information for new DBPs (beyond those currently regulated and/or studied) for prioritizing future health effects studies. An effort was made to select plants treating water that was high in total organic carbon and/or bromide to enable the detection of priority DBPs that contained bromine and/or iodine. THMs and haloacetic acids (HAAs) represented the two major classes of halogenated DBPs formed on a weight basis. Haloacetaldehydes represented the third major class formed in many of the waters. In addition to obtaining quantitative occurrence data, important new information was discovered or confirmed at full-scale plants on the formation and control of DBPs with alternative disinfectants to chlorine. Although the use of alternative disinfectants (ozone, chlorine dioxide, and chloramines) minimized the formation of the four regulated THMs, trihalogenated HAAs, and total organic halogen (TOX), several priority DBPs were formed at higher levels with the alternative disinfectants as compared with chlorine. For example, the highest levels of iodinated THMs-which are not part of the four regulated THMs-were found at a plant that used chloramination with no prechlorination. The highest concentration of dichloroacetaldehyde was at a plant that used chloramines and ozone; however, this disinfection scheme reduced the formation of trichloroacetaldehyde. Preozonation was found to increase the formation of trihalonitromethanes. In addition to the chlorinated furanones that have been measured previously, brominated furanones-which have seldom been analyzed-were detected, especially in high-bromide waters. The presence of bromide resulted in a shift to the formation of other bromine-containing DBPs not normally measured (e.g., brominated ketones, acetaldehydes, nitromethanes, acetamides). Collectively, -30 and 39% of the TOX and total organic bromine, respectively, were accounted for (on a median basis) bythe sum of the measured halogenated DBPs. In addition, 28 new, previously unidentified DBPs were detected.These included brominated and iodinated haloacids, a brominated ketone, and chlorinated and iodinated aldehydes.     

Stability of virgin olive oil and behaviour of its natural antioxidants under medium temperature accelerated storage conditions

The aim of the present research is to advance the study of virgin olive oil stability, in particular the behaviour of its natural antioxidants during long term storage. The changes undergone by tocopherols and complex and simple phenolic compounds and their antioxidant activity were studied under medium temperature (50 °C) accelerated oxidation conditions over a storage period of 8 months. Different oxygen availability (open and closed bottles, OB and CB) and four different monovarietal Tunisian virgin olive oils (VOO; Chemlali, Chétoui, El Hor and Oueslati) which vary in their fatty acid profile and content of natural antioxidants were employed. Oueslati VOO showed the lowest initial oxidation rate (4.6 PV/week) and as a consequence the highest induction period (IP; 16 days) as compared to the other VOOs studied (initial rate from 7.7 to 12.1 PV/week and IP from 9 to 12 days for El Hor and Chemlali, respectively, in both cases). In all cases the complete depletion of α-tocopherol corresponded with the observed induction period. Since the oxidation rate in the varieties studied is not sufficiently different to explain the great differences in the initial degradation rate observed in the phenolic compounds (mainly between Chétoui VOO, 163 μmol/kg/week, as compared to the other VOO oils, e.g. 6.1 and 2.5 μmol/kg/week, respectively, in Chemlali and El Hor VOOs), a concentration dependent degradation rate of complex phenols is suggested.     

NRN1 Gene as a Potential Marker of Early-Onset Schizophrenia: Evidence from Genetic and Neuroimaging Approaches

Included in the neurotrophins family, the Neuritin 1 gene (NRN1) has emerged as an attractive candidate gene for schizophrenia (SZ) since it has been associated with the risk for the disorder and general cognitive performance. In this work, we aimed to further investigate the association of NRN1 with SZ by exploring its role on age at onset and its brain activity correlates. First, we developed two genetic association analyses using a family-based sample (80 early-onset (EO) trios (offspring onset ≤ 18 years) and 71 adult-onset (AO) trios) and an independent case–control sample (120 healthy subjects (HS), 87 EO and 138 AO patients). Second, we explored the effect of NRN1 on brain activity during a working memory task (N-back task; 39 HS, 39 EO and 39 AO; matched by age, sex and estimated IQ). Different haplotypes encompassing the same three Single Nucleotide Polymorphisms(SNPs, rs3763180–rs10484320–rs4960155) were associated with EO in the two samples (GCT, TCC and GTT). Besides, the GTT haplotype was associated with worse N-back task performance in EO and was linked to an inefficient dorsolateral prefrontal cortex activity in subjects with EO compared to HS. Our results show convergent evidence on the NRN1 association with EO both from genetic and neuroimaging approaches, highlighting the role of neurotrophins in the pathophysiology of SZ.     

SCA® Slows the Decline of Functional Parameters Associated with Senescence in Skin Cells

The identification of compounds and natural ingredients that can counteract tissue stress and dysfunction induced by aging in skin cells is warranted. Here, we investigated the activity of the secretion from the snail Cryptomphalus aspersa (SCA^®), an active compound with well-established beneficial effects on skin integrity and aging. To determinate its senescence-regulation mechanisms, we used a model where damage was induced by hydrogen peroxide (H₂O₂). The results showed that SCA^® positively modulated factors involved in cell senescence such as β-galactosidase and cell morphology, secretory efficiency markers (SIRT1/6 and carboxymethyl-lysine), and metabolic and redox homeostasis (mTOR and ROS). This study demonstrated a novel compound that is activity-modulating, reduces cell senescence, and increases longevity to maintain skin homeostasis and functionality.     

Fabrication and characterization of Nb2O5-doped 3Y-TZP materials sintered by microwave technology

The purpose of this research is focused on the manufacture and characterization of a partially stabilized zirconia ceramic with 3 mol% of Yttria and doped with .5 and 1.5 mol% of Nb₂O₅ to analyze the influence of doping, with the purpose of improving the properties before hydrothermal degradation. In the first instance, the microwave sintering process was used for the consolidation of this material, then the physical and mechanical properties were characterized. Together, the results obtained by the conventional sintering process were compared. A low hydrothermal degradation study (LTD) is presented at low temperatures in which possible changes in the mechanical properties of the ceramic materials are analyzed and its influence on the phase transformation that zirconia may present is observed. The mechanical properties were evaluated through hardness, fracture toughness, and Young's modulus tests. Likewise, their density was analyzed, and microstructure was characterized by FESEM. It was found that the microwave-sintered samples at 1200°C exhibited superior properties of toughness than even samples sintered by conventional methods at higher temperatures (1400°C). The sample of 3Y-TZP with 1.5 mol% Nb₂O₅ sintered by microwave with <.2% of porosity achieved a maximum fracture toughness value around 40% higher than the dense monolithic 3Y-TZP material.     

Ordinal regression with explainable distance metric learning based on ordered sequences

Machine Learning - The purpose of this paper is to introduce a new distance metric learning algorithm for ordinal regression. Ordinal regression addresses the problem of predicting classes for...     

Implementation of Decision Trees as an Alternative for the Support in the Decisionmaking within an Intelligent System in Order to Automatize the Regulation of the Vocs in Non-Industrial Inside Environments

Natural ventilation is a component that provides a positive impact in the quality of air conditions in indoor environments, especially in non-industrial buildings. The maintenance of a continuous entrance of outside air through windows provides to the indoor a feasible and affordable manner to regulate and sustain low standards in theVOC (Volatile Organic Compounds). The technology and the Human Computer-Interaction have contributed to the creation of Intelligent Environments (EI) that provides to humans being a positive and non-intrusive responsiveness of the environment to improve their quality of life in daily activities. The Decision Trees for Decision Making is a mathematical analysis suitable for taking decision. This method will provide an intelligent system with the existent variables in the context that establish the requirement of the natural ventilation. The present paper shows the use of the Decision Trees as an analytical method for the decision making that can be apply in an intelligent system, in the automatize of the natural ventilation in a non-industrial closed environment. This method allows the incorporation of outside air and regulate in a significant manner the Volatile Organic Compounds presents in any occupied building. It was found that the application of Decision Trees and Shannon Entropies provide a feasible procedure for the diagnose of a real backdrop that enable the creation of a routing path for the decision making through the application the computation technology.     

Effect of milling and sieving processes on the physicochemical properties of okra seed powders

The aim of this work was on one hand to investigate the influence of milling speed and mean particle size of granulometric classes of okra (Abelmoschus esculentus (L.) Moench) seed powders on proximal composition (related to nutritional potential). On the other hand, it was tried to relate flow properties to powder physicochemical characteristics, namely particle size distribution and proximal composition. Then, dry okra seeds were ground with an ultra-centrifugal mill at three rotational speeds, 6 000, 12 000 and 18 000 r.p.m., corresponding to circa 990, 3 958 and 8 906 g , respectively. Each powder was separated into four granulometric classes: ≥500, 315–500, 180–315 and ≤180 µm. Milling speed affected the particle size distribution of dry okra seed powders: on one hand, the higher the milling speed, the lower the mean particle size, mainly because of the higher the proportion of fine particles (<100 µm); on the other hand, at low milling speed, dry okra seed powders were rather monomodal and constituted of large particles, whereas at high milling speed they were bimodal and composed of two populations (fine and large particles). In granulometric classes, fat and protein contents were significantly higher for fine particles, unlike carbohydrate and ash contents that were lower. This differential distribution of macronutrients within granulometric classes was enhanced at higher milling speed. Finally, the ≤180 µm granulometric class, corresponding to the smallest mean particle size, had a low flowability, confirmed by their high cohesion and compressibility, which can be related to its high fat content making it sticky. On the contrary, the ≥500 µm granulometric class was not cohesive, leading to good flow properties.