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Buddlejasaponin I and saikosaponin 1 and 2, biologically active compounds from Scrophularia scorodonia and Bupleurum rigidum respectively, exert potent in vivo antiinflammatory effects on mouse ear edema induced by phorbol myristate acetate (PMA). The effects of these compounds on swelling and other inflammatory parameters are described. In screening for in vitro effects of saikosaponins on cellular systems generating cyclooxygenase (COX) and lipoxygenase (LOX) metabolites, we observed that most saikosaponins showed a significant effect. The action is more marked on LOX metabolite LTC4. Our data support the inhibition of arachidonic acid metabolism as one of the biochemical mechanisms that might be the rationale for the putative antiphlogistic activity of these saikosaponins.  相似文献   
43.
Supramolecular organized multilayers composed of glucose oxidase (GOx) and osmium-derivatized poly(allylamine) redox polymer have been self-assembled electrostatically from Os-polyelectrolyte solutions of variable pH (5.5-8.8) leading to a decrease of the linear charge density in the PAH-Os with increasing pH. The layer-by-layer enzyme multilayers were studied by ellipsometry, quartz crystal microbalance, AFM, cyclic voltammetry, and electrocatalytic oxidation of beta-D-glucose. At higher adsorption solution pH, an increase in the film thickness, enzyme loading, and redox charge was observed. While the electrocatalytic response increases with the increase of the adsorption solution pH (decrease of the polyelectrolyte linear charge), the FADH2 oxidation bimolecular rate constant has a maximum in the pH range 7.0-7.5 where a change in the film growth mechanism is observed.  相似文献   
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First examples of multichain (polycatenar) compounds, based on the π-conjugated [1]benzothieno[3,2-b]benzothiophene unit are designed, synthesized, and their soft self-assembly and charge carrier mobility are investigated. These compounds, terminated by the new fan-shaped 2-brominated 3,4,5-trialkoxybenzoate moiety, form bicontinuous cubic liquid crystalline (LC) phases with helical network structure over extremely wide temperature ranges (>200 K), including ambient temperature. Compounds with short chains show an achiral cubic phase with the double network, which upon increasing the chain length, is at first replaced by a tetragonal 3D phase and then by a mirror symmetry is broken triple network cubic phase. In the networks, the capability of bypassing defects provides enhanced charge carrier mobility compared to imperfectly aligned columnar phases, and the charge transportation is non-dispersive, as only rarely observed for LC materials. At the transition to a semicrystalline helical network phase, the conductivity is further enhanced by almost one order of magnitude. In addition, a mirror symmetry broken isotropic liquid phase is formed beside the 3D phases, which upon chain elongation is removed and replaced by a hexagonal columnar LC phase.  相似文献   
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Due to the pollution characteristics of the wastewater generated in piggeries, these waste streams have to be treated before discharging into the environment. These wastes have a high content of organic matter, nitrogen and phosphorus that can be converted or recovered into valuable products. The valuation of swine waste by anaerobic digestion has already been assessed, but no systematic review on the technologies used for recovering nutrients from this waste has been reported to date. Therefore, the present work has the goal of presenting the most studied technologies to different scales of recovery of carbon (i.e. organic matter), nitrogen and phosphorus from swine waste. The main characteristics and parameters of the processes involved in these technologies (mainly air stripping, membrane, enhance biological phosphorus removal and struvite formation) are also highlighted, pointing out its advantages and disadvantages and posing some final feasibility considerations on the subject addressed. Experiments reported in the literature proved that technologies used for nutrient recovery from swine waste are mostly applied to the effluents previously treated by anaerobic digestion as a primary treatment, and greater effort is required for the future implementation of these technologies in large scale. © 2020 Society of Chemical Industry  相似文献   
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Abstract

This review concerns three legume trees (family Fabaceae, subfamily Caesalpinioideae) from West Africa, namely Detarium microcarpum, Parkia biglobosa and Dialium guineense, and illustrates their nutritional value and therapeutic properties. These species are an important source of nutrition for West African populations, but their agricultural exploitation is still incomplete. The survey was conducted on Scopus, Web of Science, and Medline, using scientific and common English names of the species as keywords and then selecting papers related to nutritional and medicinal properties. Main food products are fruit pulp and seeds, though leaves can also be used. Most relevant dietary features are high protein, vitamin, and micronutrient contents. Various therapeutic and nutritional benefits of these plants have been documented by ethnobotanical and experimental studies, stimulating an interest for their possible use as functional food or drug sources. Most studied medicinal properties include antidiabetic and antimicrobial activities of D. microcarpum, cardiovascular protective and antidiabetic activities of P. biglobosa, and bilharzia-preventing molluscicidal activity of D. guineense. Phytochemical characterizations have revealed potential sources of active drugs, such as D. guineense saponins and D. microcarpum diterpenes. Scientific results support popular uses of these legume trees, indicating a prominent nutritional and health value.  相似文献   
49.

In evaluating the change detection algorithms, the algorithm evaluated must show a superior performance than the state-of-the-art algorithms. The evaluation process steps comprise executing a new algorithm to segment a set of videos from a dataset and compare the results regarding a ground truth. In this paper, we propose using additional information in evaluating change detection algorithms: the level of difficulty in classifying a pixel. First, for each video frame used in the evaluation, we created a difficulty map structure, which stores values representing the level of difficulty required by an algorithm to classify each pixel of that frame. Second, we developed a metric to estimate each dataset video’s difficulty based on our difficulty maps. Third, we applied the metric to selecting the more representative videos from the dataset based on their difficulty level. Finally, to demonstrate the method’s contribution, we evaluated it using all videos from the CDNet 2014 dataset. The results showed that a subset of videos selected by our method has the same potential as the original CDNet 2014 dataset. Hence, a new change detection algorithm can be evaluated more quickly using our subset of videos selected.

  相似文献   
50.
Emulsion detonation synthesis (EDS) is a newly developed process to synthesize nano‐sized ceramic powders based on the detonation of 2 water‐in‐oil emulsions. The process provides high pressure and temperature along with rapid quenching. In this work, we report the formation of wurtzite phase BN (w‐BN) for the first time by EDS process, using hexagonal BN (h‐BN) as the precursor. Characterization studies demonstrated the formation of w‐BN with sizes varying from nanometer to micrometer scale either embedded in or grown from h‐BN matrix. These findings provide a new avenue to synthesize metastable and superhard BN phases.  相似文献   
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