Automatic generation of PLC automation projects from component-based models

Industrial process measurement and control systems (IPMCS) are used in most of the industrial sectors to achieve production improvement, process optimization and time and cost reduction. Integration, reuse, flexibility and optimization are demanded to adapt to a rapidly changing and competitive market. In order to achieve these goals, the use of standards in the application field, methodologies for defining the application design and tools for supporting the development cycle are needed. This paper proposes a component-based model of the implementation of the control system under design (the hardware and software architectures). The software architecture is defined to follow the software model of the IEC 61131-3 standard for programming programmable logic controllers and the hardware architecture is composed by equipment characterised by vendor and range of product. The proposed modelling is implemented as a markup language that allows to describe models of industrial control systems (icsML). From the application model, described in the markup language, the automation project for every programmable logic controller (PLC) present in the application is automatically generated.     

A simple model to describe the thixotropic behavior of paints

A simple rheological model is proposed to describe the thixotropic behavior of paints since the classical hysteresis area, which is usually employed, is not enough to evaluate thixotropy. The model, which is based on the assumption that viscosity is a direct measure of the structural level of the paint, depends on two equations: the Cross–Carreau equation to describe the equilibrium viscosity and a second order kinetic equation to express the time dependence of viscosity. Two characteristic thixotropic times are distinguished: one for the net structure breakdown, which is defined as a power law function of shear rate, and another for the net structure buildup, which does not depend on the shear rate. The useful information provided by these two kinetic processes can be potentially used to improve both the quality and applicability of paints.     

Infection of Brain Pericytes Underlying Neuropathology of COVID-19 Patients

A wide range of neurological manifestations have been associated with the development of COVID-19 following SARS-CoV-2 infection. However, the etiology of the neurological symptomatology is still largely unexplored. Here, we used state-of-the-art multiplexed immunostaining of human brains (n = 6 COVID-19, median age = 69.5 years; n = 7 control, median age = 68 years) and demonstrated that expression of the SARS-CoV-2 receptor ACE2 is restricted to a subset of neurovascular pericytes. Strikingly, neurological symptoms were exclusive to, and ubiquitous in, patients that exhibited moderate to high ACE2 expression in perivascular cells. Viral dsRNA was identified in the vascular wall and paralleled by perivascular inflammation, as signified by T cell and macrophage infiltration. Furthermore, fibrinogen leakage indicated compromised integrity of the blood–brain barrier. Notably, cerebrospinal fluid from additional 16 individuals (n = 8 COVID-19, median age = 67 years; n = 8 control, median age = 69.5 years) exhibited significantly lower levels of the pericyte marker PDGFRβ in SARS-CoV-2-infected cases, indicative of disrupted pericyte homeostasis. We conclude that pericyte infection by SARS-CoV-2 underlies virus entry into the privileged central nervous system space, as well as neurological symptomatology due to perivascular inflammation and a locally compromised blood–brain barrier.     

Postprandial and short-term effects of dietary virgin olive oil on oxidant/antioxidant status

It is generally believed that virgin olive oil consumption has beneficial effects, but little is known about its effects postprandially on oxidant/antioxidant status. The aim of this study was to determine changes in oxidative stress biomarkers and lipid profile after a single dose of virgin olive oil and after 1 wk of daily consumption. Sixteen subjects (9 men, 7 women) ingested 50 mL of virgin olive oil in a single dose. Blood samples were collected from 0 to 24 h. Thereafter, 14 participants (8 men, 6 women) followed a 1-wk 25 mg/d virgin olive oil dietary intervention. Blood samples were collected at the end of this period. Serum TAG (P=0.016), plasma FA (P<0.001) and lipid peroxidation products in plasma (P<0.001) and VLDL (P=0.007) increased, reaching a peak at 4–6 h, and returning to baseline values at 24 h after oil ingestion. The opposite changes were observed in plasma glutathione peroxidase (P=0.001) and glutathione reductase (GR) (P=0.042). No changes in LDL lipid peroxidation or resistance to oxidation were observed postprandially. At 24 h, plasma oleic acid remained increased (P<0.05) and resistance of LDL to oxidation improved (P<0.05). After 1 wk of virgin olive oil consumption, plasma oleic acid (P=0.031), resistance of LDL to oxidation (P<0.05), and plasma GR activity (P=0.005) increased. These results indicate that changes in oxidant/antioxidant status occur after oral virgin olive oil. Virgin olive oil consumption could provide short-term benefits for LDL resistance to oxidation and in glutathione-related enzyme activities.     

Porous silicon microcavities: synthesis, characterization, and application to photonic barcode devices

ABSTRACT: We have recently developed a new type of porous silicon we name as porous silicon colloids. They consist of almost perfect spherical silicon nanoparticles with a very smooth surface, able to scatter (and also trap) light very efficiently in a large-span frequency range. Porous silicon colloids have unique properties because of the following: (a) they behave as optical microcavities with a high refractive index, and (b) the intrinsic photoluminescence (PL) emission is coupled to the optical modes of the microcavity resulting in a unique luminescence spectrum profile. The PL spectrum constitutes an optical fingerprint identifying each particle, with application for biosensing.In this paper, we review the synthesis of silicon colloids for developing porous nanoparticles. We also report on the optical properties with special emphasis in the PL emission of porous silicon microcavities. Finally, we present the photonic barcode concept.     

In vitro biosynthesis of prostaglandin E2 by kidney medulla of essential fatty acid deficient rats

Weanling rats were fed either a semi-synthetic diet with no fat, with 28% by wt partially hydrogenated fish oil, or with 28% by wt arachis oil (control diet) for 6 or 71/2 months. The in vitro conversion of arachidonic acid to prostaglandin E₂ by homogenates of the rat kidney medulla was measured by gaschromatography with electron capture detection. The kidney medulla of essential fatty acid deficient animals showed increased activity for the in vitro conversion of exogenous arachidonic acid to prostaglandin E₂ when compared to the controls. The change of the enzymatic activity in the essential fatty acid deficient animals was reversible, as shown by refeeding. Inhibition of the prostaglandin synthetase was found at exogenous substrate concentrations higher than 50–100 μM.     

Association Between Increased DNA Mutational Frequency and Thermal Inactivation of Aerosolized Bacillus Spores Exposed to Dry Heat

Inactivation of viable bioaerosol particles, especially stress-resistant microorganisms, has important implications for biodefense and air quality control. It has earlier been shown that the loss of viability of bacterial endospores due to exposure to dry heat is associated with mutational damage. Previous studies, however, used non-aerosolized spores, long exposure times, and moderately elevated temperatures. This study was designed to investigate the mechanism of inactivation of aerosolized Bacillus endospores exposed to high temperatures for sub-second time periods. Bioaerosol was tested in a continuous air flow chamber under two flow rates, 18 L/min and 36 L/min. The chamber had a cylindrical electric heating element installed along its axis. The estimated characteristic exposure temperature (T_exposure ) ranged from 164°C to 277°C (with an uncertainty of 21–26°C). To quantify mutational frequency, spores were cultivated after dry heat exposure on tryptic-soy agar and on antibiotic nalidixic acid media. Increases in the exposure temperature caused viability loss and increase in mutational frequency of the spore DNA. Significant association was found between the inactivation factor and the mutational frequency ratio (heat exposed versus non-exposed) with R² of 0.985 for both flow rates combined. The results suggest that mutational damage is involved in the causal chain of events leading to inactivation of aerosolized endospores exposed to heat for sub-second time periods.     

Imbalances in TCA,Short Fatty Acids and One-Carbon Metabolisms as Important Features of Homeostatic Disruption Evidenced by a Multi-Omics Integrative Approach of LPS-Induced Chronic Inflammation in Male Wistar Rats

Chronic inflammation is an important risk factor in a broad variety of physical and mental disorders leading to highly prevalent non-communicable diseases (NCDs). However, there is a need for a deeper understanding of this condition and its progression to the disease state. For this reason, it is important to define metabolic pathways and complementary biomarkers associated with homeostatic disruption in chronic inflammation. To achieve that, male Wistar rats were subjected to intraperitoneal and intermittent injections with saline solution or increasing lipopolysaccharide (LPS) concentrations (0.5, 5 and 7.5 mg/kg) thrice a week for 31 days. Biochemical and inflammatory parameters were measured at the end of the study. To assess the omics profile, GC-qTOF and UHPLC-qTOF were performed to evaluate plasma metabolome; ¹H-NMR was used to evaluate urine metabolome; additionally, shotgun metagenomics sequencing was carried out to characterize the cecum microbiome. The chronicity of inflammation in the study was evaluated by the monitoring of monocyte chemoattractant protein-1 (MCP-1) during the different weeks of the experimental process. At the end of the study, together with the increased levels of MCP-1, levels of interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-α) and prostaglandin E2 (PGE2) along with 8-isoprostanes (an indicative of oxidative stress) were significantly increased (p-value < 0.05). The leading features implicated in the current model were tricarboxylic acid (TCA) cycle intermediates (i.e., alpha-ketoglutarate, aconitic acid, malic acid, fumaric acid and succinic acid); lipids such as specific cholesterol esters (ChoEs), lysophospholipids (LPCs) and phosphatidylcholines (PCs); and glycine, as well as N, N-dimethylglycine, which are related to one-carbon (1C) metabolism. These metabolites point towards mitochondrial metabolism through TCA cycle, β-oxidation of fatty acids and 1C metabolism as interconnected pathways that could reveal the metabolic effects of chronic inflammation induced by LPS administration. These results provide deeper knowledge concerning the impact of chronic inflammation on the disruption of metabolic homeostasis.     

Alterations in Metabolome and Microbiome Associated with an Early Stress Stage in Male Wistar Rats: A Multi-Omics Approach

Stress disorders have dramatically increased in recent decades becoming the most prevalent psychiatric disorder in the United States and Europe. However, the diagnosis of stress disorders is currently based on symptom checklist and psychological questionnaires, thus making the identification of candidate biomarkers necessary to gain better insights into this pathology and its related metabolic alterations. Regarding the identification of potential biomarkers, omic profiling and metabolic footprint arise as promising approaches to recognize early biochemical changes in such disease and provide opportunities for the development of integrative candidate biomarkers. Here, we studied plasma and urine metabolites together with metagenomics in a 3 days Chronic Unpredictable Mild Stress (3d CUMS) animal approach that aims to focus on the early stress period of a well-established depression model. The multi-omics integration showed a profile composed by a signature of eight plasma metabolites, six urine metabolites and five microbes. Specifically, threonic acid, malic acid, alpha-ketoglutarate, succinic acid and cholesterol were proposed as key metabolites that could serve as key potential biomarkers in plasma metabolome of early stages of stress. Such findings targeted the threonic acid metabolism and the tricarboxylic acid (TCA) cycle as important pathways in early stress. Additionally, an increase in opportunistic microbes as virus of the Herpesvirales was observed in the microbiota as an effect of the primary stress stages. Our results provide an experimental biochemical characterization of the early stage of CUMS accompanied by a subsequent omic profiling and a metabolic footprinting that provide potential candidate biomarkers.     

Cellulase and Bacterial Inoculant Effects on Cocksfoot and Lucerne Ensiled at High Dry Matter Levels

Limited information exists on the response of grass and legume silage to enzyme and bacterial inoculant treatments when wilted to drier than desired conditions. This study was undertaken to evaluate the impact of cellulase (from Trichoderma longibrachiatum) application rate, when combined with a bacterial inoculant (Lactobacillus plantarum and Pediococcus cerevisiae), on the fermentation characteristics of cocksfoot (Dactylis glomerata L) and lucerne (Medicago sativa L) ensiled at high dry-matter concentrations. Forages were wilted to near 600 g dry matter kg^-1 and cellulase, combined with inoculant, was applied at 0·30 ml kg^-1 herbage and at two, four and eight times this concentration (at least 2500 IU ml^-1). Cellulase was also applied alone at 0·60 ml kg^-1. Wilted forages were ensiled in laboratory silos for 60 days. Effect of cellulase application rate on neutral detergent fibre concentrations of the silages was small and inconsistent. Averaged across species, only the intermediate cellulase concentrations decreased neutral detergent fibre concentration (P=0·082). The limited cell-wall degradation was probably related to the high silage dry-matter and lignin concentrations. Cellulase combined with inoculant increased total fermentation, when averaged across species. In cocksfoot, cellulase combined with inoculant decreased pH and NH₃-N concentration but increased the lactic: acetic acid ratio of control silage, with most of the effect caused by the inoculant. Cellulase applied alone to lucerne caused a higher lactic: acetic acid ratio than the control or when combined with the inoculant at the same cellulase rate. Thus, the effect of cellulase–inoculant mixtures on silage quality varied among plant species, with cocksfoot generally more responsive than lucerne. © 1997 SCI.