Synthesis and characterization of moisture cured prepolymer polyurethane films

Polyurethane prepolymers are a group of materials representing a reactive intermediate betweenmonomeric isocyanates and polyurethane polymers. They are the polycondensation reaction product of adiisocyanate (hard segments) and a material with hydroxyl functionality such as a polyol -glycol of high molecular weight (flexible segments). Most polyols used in polyurethane synthesis arebased on polyether, polyester or polycarbonate structures. About isocyanate, its structure determines itsreactivity and is known that aliphatic isocyanates are less reactive than aromatic ones.The properties of these prepolymers and the final products (adhesives, sealants and coatings) can be tunedby selecting suitable polyol and isocyanate components, as well as their molar ratio. When wateremulsifiable polymers are intended, anionic monomer dimethylolpropionic acid (DMPA) is incorporatedin the chain as internal emulsifier.The aim of this work was to synthesize and characterize moisture cured polyurethane prepolymers forhigh gloss coating applications. Desired resin must be emulsifiable in water (for easy cleaning of thereactor and auxiliary equipment) and the respective coating must be transparent, colorless and tack free.The following parameters were studied: chemical nature and molecular weight of polyol (polyether andpolycarbonate, from 400 to 2000 molecular weight), initial molar ratio of isocyanate to hydroxyl groups(NCO/OH ratio from 1.5 to 2.5) and presence or absence of DMPA. The isocyanate used was alwaysisophorone diisocyanate.The coatings obtained were caharacterized in terms of thermal stability, Buchholz hardness, scratchresistance, tack, gloss and yellowness index. The results were analysed and related to the expectedpolymer structures for the different cases. The best performance was obtained for polycarbonate polyolwith higher NCO/OH ratio and containing DMPA

Intelligent machining methods for Ti6Al4V: a review

Digital manufacturing is a necessity to establishing a roadmap for the future manufacturing systems projected for the fourth industrial revolution. Intelligent features such as behavior prediction, decision- making abilities, and failure detection can be integrated into machining systems with computational methods and intelligent algorithms. This review reports on techniques for Ti6Al4V machining process modeling, among them numerical modeling with finite element method (FEM) and artificial intelligence- based models using artificial neural networks (ANN) and fuzzy logic (FL). These methods are intrinsically intelligent due to their ability to predict machining response variables. In the context of this review, digital image processing (DIP) emerges as a technique to analyze and quantify the machining response (digitization) in the real machining process, often used to validate and (or) introduce data in the modeling techniques enumerated above. The widespread use of these techniques in the future will be crucial for the development of the forthcoming machining systems as they provide data about the machining process, allow its interpretation and quantification in terms of useful information for process modelling and optimization, which will create machining systems less dependent on direct human intervention.publishe

Jatrophane and lathyrane diterpenoids from Euphorbia hyberna L

A new diterpene tetraester, from the jatrophane family, and two new diterpene triesters, with a lathyrane skeleton, have been isolated from the chloroform extract of the roots of Euphorbia hyberna L. The structures of these compounds have been established by spectroscopic methods, including 2D NMR experiments.info:eu-repo/semantics/publishedVersio

Determining factors related to impaired spinal and hip mobility in patients with axial spondyloarthritis : longitudinal results from the DESIR cohort

Copyright information: © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.Objective: To investigate the determinants of impaired spinal and hip mobility in patients with early axial spondyloarthritis (axSpA). Methods: Five-year longitudinal data from the DEvenir des Spondyloarthrites Indifférenciées Récentes (DESIR) cohort were analysed. Associations were investigated using generalised estimating equations, using Bath Ankylosing Spondylitis Metrology Index (BASMI) linear or each of the five components of BASMI as dependent variables, and clinical and demographic variables as independent variables in univariable models. Multivariable analyses were performed, adjusting for potential confounders. Results: Data from 644 patients and 5152 visits were analysed. Higher BASMI values were independently and positively associated with Ankylosing Spondylitis Disease Activity Score C reactive protein (ASDAS-CRP) (adjusted B (adjB)=0.21; 95% CI=0.15 to 0.28), MRI spinal inflammation score (adjB=0.11; 95% CI=0.04 to 0.19), enthesitis score (adjB=0.02; 95% CI=0.01 to 0.04) and age (adjB=0.02; 95% CI=0.01 to 0.03). All BASMI components were independently associated with ASDAS-CRP and MRI spinal inflammation, except for maximal intermalleolar distance (reflecting hip mobility), which was not associated with MRI spinal inflammation. Conclusion: In early axSpA, spinal mobility impairment is independently determined by clinical disease activity, MRI spinal inflammation, enthesitis and age. The influence of spinal inflammation prevails in early axSpA, as opposed to spinal structural damage, which may become more relevant in later disease stages.info:eu-repo/semantics/publishedVersio

Chemical constituents of Euphorbia hyberna L. (Euphorbiaceae)

Chemical investigation of the aerial part and the roots of Euphorbia hyberna L. subs. hyberna. resulted in the isolation and identification of four triterpenoids (3�-O-octadecanoyllupeol (1), glut-5-en-3�-ol (2), 24-methylenecicloartan-3�-ol (3) and cicloart-23-ene-3�,25-diol (6)) along with the phenolic compounds ellagic acid (4) and 3,30 -di-O-methylellagic acid (7). Although these are all known compounds, this is the first report of their isolation from this plant. Their structures were elucidated on the basis of spectral methods, including 2D NMR experiences, and confirmed by comparing with the literature data.info:eu-repo/semantics/publishedVersio

The Role of Ghrelin in Regulating Synaptic Function and Plasticity of Feeding-Associated Circuits

Synaptic plasticity of the neuronal circuits associated with feeding behavior is regulated by peripheral signals as a response to changes in the energy status of the body. These signals include glucose, free fatty acids, leptin and ghrelin and are released into circulation, being able to reach the brain. Ghrelin, a small peptide released from the stomach, is an orexigenic hormone produced in peripheral organs, and its action regulates food intake, body weight and glucose homeostasis. Behavioral studies show that ghrelin is implicated in the regulation of both hedonic and homeostatic feeding and of cognition. Ghrelin-induced synaptic plasticity has been described in neuronal circuits associated with these behaviors. In this review, we discuss the neuromodulatory mechanisms induced by ghrelin in regulating synaptic plasticity in three main neuronal circuits previously associated with feeding behaviors, namely hypothalamic (homeostatic feeding), ventral tegmental (hedonic and motivational feeding) and hippocampal (cognitive) circuits. Given the central role of ghrelin in regulating feeding behaviors, and the altered ghrelin levels associated with metabolic disorders such as obesity and anorexia, it is of paramount relevance to understand the effects of ghrelin on synaptic plasticity of neuronal circuits associated with feeding behaviors

Determinants of health-related quality of life in spondyloarthritis and rheumatoid arthritis: data from the COMOSPA and COMORA studies

© 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Objectives: To assess the hierarchy of outcomes contributing to health-related quality of life (HRQoL) in spondyloarthritis (SpA) and rheumatoid arthritis (RA). Methods: Data from the international cross-sectional COMOSPA and COMORA studies were used. HRQoL was assessed using the EuroQOL 5-dimension 3-level (EQ-5D-3 L). First, multivariable linear regression models were used to identify associations between EQ-5D-3 L (dependent variable) and several demographic and clinical variables (independent variables). Second, a decision tree was built using Chi-square Automatic Interaction Detector, a method of unbiased hierarchical multivariable analysis (dependent variable: EQ-5D-3 L). Results: In total, 3984 patients with SpA and 3920 patients with RA were included. In SpA, HRQoL was associated with BASFI (adjusted B=-0.006; 95%CI=-0.007 to -0.005), ASDAS (-0.052; -0.071 to -0.033), work productivity loss score (-0.002; -0.003 to -0.002), NSAID treatment (-0.052; -0.083 to -0.020), bDMARD treatment (-0.051; -0.082 to -0.021), university education (-0.051; -0.075 to -0.027) and radiographic sacroiliitis (0.035; 0.004 to 0.030). In RA, HRQoL was associated with modified Health Assessment Questionnaire (MHAQ) (-0.220, -0.253 to -0.188), DAS28-CRP-3v (-0.027, -0.036 to -0.018), work productivity loss score (-0.003, -0.003 to -0.002), presence of erosions (-0.042, -0.065 to -0.020), alcohol consumption ≥3 units/day (0.012, 0.001 to 0.024)) and csDMARD treatment (0.034, 0.001 to 0.066). The decision tree revealed BASFI and MHAQ as first variables with the most discriminative power on EQ-5D-3 L, followed by work productivity loss and disease activity, in both SpA and RA cohorts. Conclusion: In SpA and RA, physical function is the main contributor to HRQoL measured by EQ-5D-3 L, followed by disease activity and work productivity loss.info:eu-repo/semantics/publishedVersio

Editorial: Human impacts on bats in tropical ecosystems: sustainable actions and alternatives

Globally, the most extraordinary biodiversity is in the tropics, spread in a great diversity of vegetation types and habitats. Among the myriad mammalian groups, bats stand out for their remarkable taxonomic, functional, and phylogenetic diversity (Wilson and Mittermeier, 2019). Within the tropics, bats can be found in different vegetation types varying in a gradient of structural complexity from dense ancient forests to more open landscapes and woodlands in the savannas and fields (Meyer et al., 2004; Carvalho et al., 2021). Bats provide essential ecosystem services such as seed dispersal and pollination of the many plants that have a role in the income of the most impoverished human populations and the formal economy (Lacher et al., 2019). Moreover, as voracious insect predators, bats play a vital role in suppressing agricultural pests, an invaluable service in this part of the world, and disease vectors for humans (Aguiar et al., 2021; Tuneu-Corral et al., 2023). It is widely recognized that the main threat to bats globally is the extensive conversion of natural ecosystems, especially in tropical developing countries (Meyer et al., 2016). This shift in land use results in habitat loss and environmental degradation, with consequent loss of species, ecosystem services, and lineages (Frick et al., 2020; Atagana et al., 2021; Colombo et al., 2023). There is thus an urgent need to disseminate correct information about bats and explore best practices for mitigating the adverse effects stemming from human activities such as vegetation clearing for cattle ranching, agriculture, human settlements, and urbanization. Therefore, in this Research Topic, we aimed to bring together current research that assesses the influence of multiple environmental transformation drivers on the diversity of tropical bats. Nine papers were published in this Research Topic, and they present novel insights into how bats react to human-driven environmental changes and address significant gaps in bat conservation. These studies were conducted by 36 authors in six countries across the American, African and Asian continents (Figure 1). While the sampling was local in seven studies, Brasileiro et al. used data spanning Brazilian biomes, and Xavier et al. carried out a global systematic review. Three key themes emerge from the papers presented in this Research Topic, and we discuss the findings and knowledge gaps related to each theme in the following sections. Figure 1info:eu-repo/semantics/publishedVersio