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101.
1-cyclohexyl-x-methoxybenzene is a novel psychoactive substance (NPS), first discovered in Europe in 2012 as unknown racemic mixture of its three stereoisomers: ortho, meta and para. Each of these has structural similarities with the analgesic tramadol and the dissociative anesthetic phencyclidine. In light of these structural analogies, and based on the fact that both tramadol and phencyclidine are substances that cause toxic effects in humans, the aim of this study was to investigate the in vitro and in vivo pharmacodynamic profile of these molecules, and to compare them with those caused by tramadol and phencyclidine. In vitro studies demonstrated that tramadol, ortho, meta and para were inactive at mu, kappa and delta opioid receptors. Systemic administration of the three stereoisomers impairs sensorimotor responses, modulates spontaneous motor activity, induces modest analgesia, and alters thermoregulation and cardiorespiratory responses in the mouse in some cases, with a similar profile to that of tramadol and phencyclidine. Naloxone partially prevents only the visual sensorimotor impairments caused by three stereoisomers, without preventing other effects. The present data show that 1-cyclohexyl-x-methoxybenzene derivatives cause pharmaco-toxicological effects by activating both opioid and non-opioid mechanisms and suggest that their use could potentially lead to abuse and bodily harm.  相似文献   
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A large variety of cheeses exist in Brazil, reflecting historical and cultural aspects. Brazilian artisanal cheeses present differences in the processing, ripening time (when applied), type of milk used, texture, size, shape, color, moisture content, flavor, the use or not of starter cultures, among others. This review describes the main artisanal cheeses produced in Brazil, focusing on general and particular characteristics associated with their making process and geographical identity. Overall, the high variability of the physicochemical data and deficiency of information on sensorial properties of Brazilian artisanal cheeses were noticed. On the other hand, culture‐dependent methods were mostly used to expand the knowledge into the microbiology of these cheeses, whereas their microbial diversity has been recently discovered through the use of 16S rRNA gene sequencing‐based methods. The certification of a geographical indication for Brazilian artisanal cheeses may encompass an essential milestone for adding value to these products. Regardless of their significance in the diet, culture, and economy of producing regions, taken together, the reviewed literature discloses the need of insightful studies to generate scientific data to support the expansion of the market, while ensuring the protection of historic aspects related to the production of Brazilian artisanal cheeses.  相似文献   
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Fossil fuel combustion is one of the major means to meet the mounting global energy demand. However, the increasing NOx and N2O emissions arising from fossil fuel combustion process have hazardous effects. Thus, mitigating these gases is vital to attain a sustainable environment. Interestingly, oxy-fuel combustion in fluidized bed for carbon capture and minimized NOx emissions is strongly sustainable compare to the other approaches. It was assessed that NOx formation and fuel-N conversion have significant limitation under oxy-fluidized bed compared to air mode and the mechanism of NOx formation is still deficient and requires further development. In addition, this review paper discussed the potential of primary measure as low emission process with others supplementary techniques for feasible NOx reduction. The influences of combustion mode, operating parameters, and reduction techniques such as flue gas recirculation, oxygen staging, biomass co-firing, catalyst, influence of fluidized bed design and structure, decoupling combustion and their merges are respectively evaluated. Findings show that significant minimization of NOx emission can be achieved through combination of primary and secondary reduction techniques.  相似文献   
104.
In present work, the development of macroporous monolithic layers bearing the artificial recognition sites toward L-phenylalanine has been carried out. The set of macroporous poly(2-aminoethyl methacrylate-co-2-hydroxyethyl methacrylate-co-ethylene glycol dimethacrylate) materials with average pore size ranged in 340–1200 nm was synthesized. The applicability of Hildebrand's and Hansen's theories for the prediction of polymer compatibility with porogenic solvents was evaluated. The dependences of average pore size on theoretically calculated parameters were plotted. The linear trend detected for Hansen's theory has indicated the high suitability of this approach to select appropriate porogens. The synthesized monolithic MIP layers were tested toward the ability to rebind phenylalanine-derivative in microarray format. The influence of such factors as average pore size of the material, the concentration of template molecule in polymerization mixture, interaction time of analyte with its imprinted sites on binding efficiency were studied. The developed materials demonstrated good analyte rebinding from buffer solution with recognition factors 2.5–3.4 depending on the MIP sample. The comparable rebinding efficiency was also detected when the analysis was carried using complex biological media. The selectivity of phenylalanine binding from the equimolar mixture of structural analogues was 81.9% for free amino acid and 91.2% for labeled one.  相似文献   
105.
The present study considers a possible role of enzymatic reactions in the adaptive response of cells to the beta-emitting radionuclide tritium under conditions of low-dose exposures. Effects of tritiated water (HTO) on the reactions of bacterial luciferase and NAD(P)H:FMN-oxidoreductase, as well as a coupled system of these two reactions, were studied at radioactivity concentrations ≤ 200 MBq/L. Additionally, one of the simplest enzymatic reactions, photobiochemical proton transfer in Coelenteramide-containing Fluorescent Protein (CLM-FP), was also investigated. We found that HTO increased the activity of NAD(P)H:FMN-oxidoreductase at the initial stage of its reaction (by up to 230%); however, a rise of luciferase activity was moderate (<20%). The CLM-FP samples did not show any increase in the rate of the photobiochemical proton transfer under the exposure to HTO. The responses of the enzyme systems were compared to the ‘hormetic’ response of luminous marine bacterial cells studied earlier. We conclude that (1) the oxidoreductase reaction contributes significantly to the activation of the coupled enzyme system and bacterial cells by tritium, and (2) an increase in the organization level of biological systems promotes the hormesis phenomenon.  相似文献   
106.
1,4-Butanediol (1,4-BDO) is a four-carbon diol used for industrial applications such as organic solvents, and the production of adhesives, fibers and polyurethanes. 1,4-BDO currently is produced through several petrochemical routes: hydrogenation of maleic anhydride, isomerization of propylene oxide, acetoxylation of butadiene, and the reaction between formaldehyde and acetylene. The current trends in 1,4-BDO production involve the utilization of renewable sources such as biomass. In this context, the present study aimed to identify promising technologies of 1,4-BDO production through prospecting methodology based on the analyses of patents and scientific article, describing the most relevant aspects of those emerging technologies. An increasing amount of 1,4-BDO production focused on biotechnological routes has been reported, with the US heavily involved in the development of new technologies. This study tracked three promising technologies which have potential for application in a biorefinery context because those processes involve (i) production of 1,4-BDO from sugars, classified herein as the biotechnological route; (ii) production of intermediates from sugar fermentation followed by catalytic conversion into 1,4-BDO, classified herein as the hybrid route, and (iii) furan/furfural conversion into 1,4-BDO. © 2020 Society of Chemical Industry  相似文献   
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