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81.
82.
Modified atmosphere packaging (MAP) is an efficient method to increase shelf-life of fishery products by inhibiting bacterial growth and oxidative reactions. Beside the traditional gases used for MAP, novel gases such as argon (Ar) and nitrous oxide (N2O) were approved for food use in the European Union. The present research investigates the effect of MAP with unconventional gas mixtures, that previously positively affected microbial shelf-life, on colour, lipid oxidation and sensorial characteristics of sardine fillets during storage. Four atmosphere conditions were tested: Air (20.8% O2/79.2% N2), N2 (30% CO2/70% N2), N2O (30% CO2/70% N2O) and Ar (30% CO2/70% Ar). Samples were stored for 12 days at 3 °C. Results showed that the removal of oxygen significantly inhibited the oxidation process; however, most of the investigated parameters related to fat oxidation did not show any improvement, except for a slight decrease in lipid hydrolysis and improvement in sensory properties in the packaging containing Ar.  相似文献   
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84.
Caloric restriction promotes longevity in multiple animal models. Compounds modulating nutrient-sensing pathways have been suggested to reproduce part of the beneficial effect of caloric restriction on aging. However, none of the commonly studied caloric restriction mimetics actually produce a decrease in calories. Sodium-glucose cotransporter 2 inhibitors (SGLT2-i) are a class of drugs which lower glucose by promoting its elimination through urine, thus inducing a net loss of calories. This effect promotes a metabolic shift at the systemic level, fostering ketones and fatty acids utilization as glucose-alternative substrates, and is accompanied by a modulation of major nutrient-sensing pathways held to drive aging, e.g., mTOR and the inflammasome, overall resembling major features of caloric restriction. In addition, preliminary experimental data suggest that SGLT-2i might also have intrinsic activities independent of their systemic effects, such as the inhibition of cellular senescence. Consistently, evidence from both preclinical and clinical studies have also suggested a marked ability of SGLT-2i to ameliorate low-grade inflammation in humans, a relevant driver of aging commonly referred to as inflammaging. Considering also the amount of data from clinical trials, observational studies, and meta-analyses suggesting a tangible effect on age-related outcomes, such as cardiovascular diseases, heart failure, kidney disease, and all-cause mortality also in patients without diabetes, here we propose a framework where at least part of the benefit provided by SGLT-2i is mediated by their ability to blunt the drivers of aging. To support this postulate, we synthesize available data relative to the effect of this class on: 1- animal models of healthspan and lifespan; 2- selected molecular pillars of aging in preclinical models; 3- biomarkers of aging and especially inflammaging in humans; and 4- COVID-19-related outcomes. The burden of evidence might prompt the design of studies testing the potential employment of this class as anti-aging drugs.  相似文献   
85.
The design of novel chiral ligands is at the core of asymmetric catalysis. The catalytic characteristics of a transition metal catalyst such as activity, selectivity and stability can be fine-tuned by optimization of the steric and electronic properties of the coordinating ligands. In asymmetric transformations, catalyst optimization still relies to a large extent on trial-and-error and educated guesses. New strategies based on combinatorial screening and high-throughput experimentation have been introduced for the design and optimization of new ligands and catalytic systems. Supramolecular bidentate ligands that form by self-assembly of building blocks are particularly suited for this combinatorial approach as the potential number of catalysts grows exponentially with the number of building blocks synthesized. Catalytic systems based on supramolecular interactions have proven to be highly advantageous in creating large ligand libraries for high-throughput screening, which allows optimization of activity and selectivity for a variety of reactions. In this review we describe the progress in this field.  相似文献   
86.
The acidic-subunit of 11S seed storage globulin of Amaranthus hypochondriacus was recently modified by the incorporation of antihypertensive biopeptides: four units of Val–Tyr dipeptides (VY) in tandem and one of Ile–Pro–Pro tripeptide (IPP), was named AMC3. The in vivo effect of AMC3 enzymatic hydrolysates (AEH) produced in Escherichia coli, was evaluated in spontaneously hypertensive rats (SHR) by once-oral administration experiments. As positive control a SHR group received a dose of captopril (50 mg/kg) (an angiotensin-converting enzyme (ACE) inhibitor used for the treatment of hypertension). Mean arterial pressure (MAP) was measured for 6 h after AEH or captopril administration. AEH administration at maximal dose (100 mg/kg) significantly reduced MAP similar to the group treated with captopril. The maximal reduction in MAP was observed after 3.5 h after AEH oral administration. The present study showed that enzymatic hydrolysates of AMC3 containing ACE inhibitory peptides (4xVY and IPP) sequences had significant antihypertensive action by oral administration in spontaneously hypertensive rats (SHR).  相似文献   
87.
Reviews studies on factors that may influence jurors' verdicts. These factors include characteristics of the victim and defendant, judges' instructions regarding pretrial publicity and inadmissible evidence, number and severity of decision alternatives, jurors' conception of guilt, and size of the jury and its decision rule. Data have indicated that many extra-evidential factors contribute to mock jurors' verdicts. The applicability of these results is limited, however, by the many methodological and sampling problems inherent in the studies. It is suggested that efforts to develop methods of minimizing biases would be most successful if undertaken conjointly by legal experts and social scientists. (73 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
This article describes a technique for recycling polystyrene cups (PSr) mixed with poly(butyl methacrylate) (PBMA) to produce PSr/PBMA films and subsequently PSr films by removing PBMA with a selective solvent (acetic acid), with the benefit of a reduction in environmental pollution generated by polystyrene waste. Removal of PBMA increases roughness, which generates a significant increase ( 34°) in the water contact angle, reaching its highest value at 128°. By increasing the hydrophobicity of surfaces, properties with important technical applications are acquired such as those used in antifouling paints, stain‐resistant surfaces, and surfaces that avoid the formation and accretion of ice on microelectronic devices. Roughness of PSr/PBMA films is significantly affected by the concentration of both polymers and by the spin rate, reaching its highest value at 2% PSr and 3% PBMA at 2000 . For optimal film deposition, a cheap spin coating unit was designed and built, with a price less than 4% of that of a commercially available spin coating unit. Lastly, it was found that the data obtained with our spin coating unit is described by the Meyerhofer model with accuracy of 88% ± 3%. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45365.  相似文献   
89.
This work demonstrates a new approach for building bioinorganic interfaces by integrating biologically derived silica with single-walled carbon nanotubes to create a conductive matrix for immobilization of enzymes. Such a strategy not only allows simple integration into biodevices but presents an opportunity to intimately interface an enzyme and manifest direct electron transfer features. Biologically synthesized silica/carbon nanotube/enzyme composites are evaluated electrochemically and characterized by means of X-ray photoelectron spectroscopy. Voltammetry of the composites displayed stable oxidation and reduction peaks at an optimal potential close to that of the FAD/FADH(2) cofactor of immobilized glucose oxidase. The immobilized enzyme is stable for a period of one month and retains catalytic activity for the oxidation of glucose. It is demonstrated that the resulting composite can be successfully integrated into functional bioelectrodes for biosensor and biofuel cell applications.  相似文献   
90.
Microfluidic capillary electrophoresis and real-time PCR were successfully applied to investigate the postmortem alterations in RNA extracted from fish muscular tissue in relation to three parameters: slaughtering method, time, and storage temperature.  相似文献   
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