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271.
Peter A. Bron Marta Catalayud Massimo Marzorati Marco Pane Ece Kartal Raja Dhir Gregor Reid 《International journal of molecular sciences》2021,22(17)
The human microbiome is a rich factory for metabolite production and emerging data has led to the concept that orally administered microbial strains can synthesize metabolites with neuroactive potential. Recent research from ex vivo and murine models suggests translational potential for microbes to regulate anxiety and depression through the gut-brain axis. However, so far, less emphasis has been placed on the selection of specific microbial strains known to produce the required key metabolites and the formulation in which microbial compositions are delivered to the gut. Here, we describe a double-capsule technology to deliver high numbers of metabolically active cells derived from the 24-strain probiotic product SH-DS01 to the gastrointestinal tract, including the small intestine, where immune responses and adsorption of metabolites into the bloodstream occur. Based on its genome sequence, Limosilactobacillus reuteri SD-LRE2-IT was predicted to have the genetic capacity to de novo produce a specific metabolite of interest to brain health, vitamin B12, which could be confirmed in vitro. Taken together, our data conceptualizes the importance of rationally defined microbial strain characterization based on genomics and metabolomics data, combined with carefully designed capsule technology for delivery of live cells and concomitant functionality in and beyond the gut ecosystem. 相似文献
272.
In this study, we employed an ultra-fast boriding technique to grow hard boride layers on low carbon steel substrates using an induction furnace at 900 °C. The technique utilizes an electrochemical cell in which it is possible to achieve very thick (i.e., about 90 μm thick) boride layers in about 30 min. The effects of process duration on boride layer thickness, composition, and structural morphology were investigated using microscopic and X-ray diffraction (XRD) methods. We also developed an empirical equation for the growth rate of boride layers. XRD results revealed two principal boride phases: FeB and Fe2B thickness of which was very dependent on the process duration. For example, Fe2B phase was more dominant during shorter boriding times (i.e., up to 15 min.) but FeB became much more pronounced at much longer durations. The growth rate of total boride layer was nearly linear up to 30 min of treatment. However during much longer process duration, the growth rate assumed a somewhat parabolic character that could be expressed as d = 1.4904 (t)0.5 + 11.712), where d (in μm) is the growth rate, t (in s) is duration. The mechanical characterization of the borided surfaces in plane and in cross-sections has confirmed hardness values as high 19 GPa at or near the borided surface (where FeB phase is present). However, the hardness gradually decreased to 14 to 16 GPa levels in the region where Fe2B phase was found. 相似文献
273.
274.
This article reports studies on the rotation of initially stressed thermoelastic medium with voids subjected to thermal loading due to laser pulse. The bounding plane surface is heated by a non-Gaussian laser beam. The medium rotated with a uniform angular velocity. The problem was studied in the context of Green-Naghdi (G-N) theory of types II and III using the normal mode analysis method. The comparisons between the both types II and III of (G-N) theory in the presence and the absence of the rotation, the initial stress and for two values of time for considered medium are shown graphically. 相似文献
275.
Hilal Yildiz 《International Journal of Food Properties》2016,19(7):1593-1603
This study reports the chemical composition, antioxidant, and antimicrobial activity of the essential oil and ethanol extract of Coriandrum sativum L. leaves. Gas chromatography/mass spectrometry analysis identified 19 compounds representing 95.30% of the oil. (E)-2-decenal (29.87%), linalool (21.61%), (E)-2-dodecenal (7.03%), dodecanal (5.78%), (E)-2-undecenal (3.84%), (E)-2-tridecenal (3.56%), (E)-2-hexadecenal (2.47%), tetradecenal (2.35%), and α-pinene (1.64%) were the main components identified in the essential oil. The samples were screened for their antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl radical scavenging and β-caroten bleaching assay. IC50 value for ethanol extract of C. sativum was determined as 74.87 ± 0.03 μg/mL. Total antioxidant activity value for C. sativum ethanol extract was 85.85 ± 0.04%. Total phenolic content for ethanol extract of the plant was determined as 14.97 ± 0.05 mg gallic acid equivalents/g dry weight. The essential oil and ethanol extract were also tested for antimicrobial activity against 28 different foodborne microorganisms, including 19 bacteria, 7 fungi, and 2 yeast species. The ethanol extract of the plant showed weak antimicrobial activities against microbial strains in both disc diffusion and minimal inhibition concentration tests. This study suggested that Coriandrum sativum L. leaves may be used as a potential source of food flavoring, and for their antioxidants and antimicrobial properties. 相似文献
276.
Melike Sakin-Yilmazer Tansel Kemerli Hilal Isleroglu Ozgul Ozdestan Gonul Guven Ali Uren Figen Kaymak-Ertekin 《Journal of food engineering》2013
Effects of oven type and baking temperature on acrylamide concentration, surface browning, temperature profiles and drying rates of muffins were investigated. Muffins were baked in convection and steam assisted hybrid ovens at 145, 160 and 175 °C for different baking times. For all oven types, the acrylamide concentration of muffins increased with increasing baking time and temperature (p < 0.05). The formation was considered as the first order reaction kinetics except for the lowest baking temperature at natural convection and steam assisted hybrid ovens. The reaction rate constant, k was found to be in the range of 0.027–0.078 (min−1). For the forced convection oven, the effect of baking temperature on acrylamide concentration followed the Arrhenius type of equation; with activation energy of 36.35 kJ/mol. The minimum drying rate was observed by the steam assisted hybrid oven, at all conditions. Steam assisted baking resulted in lower acrylamide concentration at all baking temperatures, while providing the average moisture content not significantly different. 相似文献
277.
An experimental study of heat transfer into gas‐fluidized beds has been carried out with heat transfer into discriminated areas of the boundary walls, and into single and multiple elements immersed in the bed. The experiments have been carried out with glass ballotini ranging in size from 100 μm to 1 mm in diameter, on Diakon (Perspex) particles of 325 μm, and on nickel particles of 275 μm and 325 μm covering a range of Archimedes numbers from 100 to 105. Beds of different diameter with distributors of several different types have been examined. The entire experimental results have been compared with literature data on heat transfer to immersed elements. It is shown that the onset of slugging in the fluidized bed has a large effect on heat transfer. Once the effect of slugging has been introduced, it is shown that the results of this investigation and others in the literature within the range of Archimedes numbers from 100 to 109 may be correlated. 相似文献
278.
M. Hilal Bilir Neslihan Şakalar Bilal Acemioğlu Evrim Baran M. Hakki Alma 《应用聚合物科学杂志》2013,127(6):4340-4351
The powders of peanut shell is first liquefied with the mixture of polyethylene glycol‐400 and monoethylene glycol (MEG) using sulfuric acid at 160°C for 2 h. Polyurethane (PU)‐type rigid foam is prepared from the reaction between peanut shell liquefied with the MEG and diphenylmethane diisocyanate. Then the PU foam is used as a sorbent for the removal of the remazol brilliant blue R from aqueous solution. The sorption of the dye increases with increasing initial concentration, temperature, and ionic strength, while decreasing with increasing pH. From the isotherm and kinetic studies, it is seen that the sorption process is in the best agreement with the Langmuir isotherm and the pseudo second‐order kinetic model. Desorption and FTIR studies show that a chemisorption process occurs between dye and foam, probably indicating electrostatic interactions. The thermodynamic parameters (i.e., standard free energy, standard enthalpy, and standard entropy) are determined, and the results obtained are discussed in detail. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci, 2013 相似文献
279.
Amani Abdulrahman Albraikan Nadhem NEMRI Mimouna Abdullah Alkhonaini Anwer Mustafa Hilal Ishfaq Yaseen Abdelwahed Motwakel 《计算机、材料和连续体(英文)》2023,74(2):2443-2459
Melanoma remains a serious illness which is a common form of skin cancer. Since the earlier detection of melanoma reduces the mortality rate, it is essential to design reliable and automated disease diagnosis model using dermoscopic images. The recent advances in deep learning (DL) models find useful to examine the medical image and make proper decisions. In this study, an automated deep learning based melanoma detection and classification (ADL-MDC) model is presented. The goal of the ADL-MDC technique is to examine the dermoscopic images to determine the existence of melanoma. The ADL-MDC technique performs contrast enhancement and data augmentation at the initial stage. Besides, the k-means clustering technique is applied for the image segmentation process. In addition, Adagrad optimizer based Capsule Network (CapsNet) model is derived for effective feature extraction process. Lastly, crow search optimization (CSO) algorithm with sparse autoencoder (SAE) model is utilized for the melanoma classification process. The exploitation of the Adagrad and CSO algorithm helps to properly accomplish improved performance. A wide range of simulation analyses is carried out on benchmark datasets and the results are inspected under several aspects. The simulation results reported the enhanced performance of the ADL-MDC technique over the recent approaches. 相似文献
280.
Pyrolysis of wood and wood-based wastes is considered to be one of the promising methods of supplying charcoal as solid material and liquids containing a number of valuable chemicals. In this study, we characterized the chemical components in the liquids from pyrolysis of solid wood and wood-based composites such as particleboard, plywood and medium density fiberboard (MDF) with phenol or urea-type adhesive. In addition, the effectiveness of the liquids to control fungal growth in vitro was examined with consideration of the bio-active components included in the liquids. Results showed that the chemical composition of the liquids obtained from solid wood were greatly different from those obtained from the composites. Fungicidal tests showed a significant difference in the effectiveness of controlling fungi between solid wood and the composites and the liquids from the composites revealed higher effectiveness against the fungi tested. 相似文献