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991.
Rui Zhang Esrat Jahan Rupa Siwen Zheng Jinnatun Nahar Deok Chun Yang Se Chan Kang Yingping Wang 《Molecules (Basel, Switzerland)》2022,27(1)
This study focused on developing Panos nanoemulsion (P-NE) and enhancing the anti-inflammatory efficacy for the treatment of inflammation. The effects of P-NE were evaluated in terms of Nitric oxide (NO production) in Lipopolysaccharide (LPS), induced RAW 264.7 cells, Reactive oxygen species (ROS) generation using Human Keratinocyte cells (HaCaT), and quantitative polymerase chain reaction (qPCR) analysis. Sea buckthorn oil, Tween 80, and span 80 were used and optimize the process. Panos extract (P-Ext) was prepared using the fermentation process. Further high-energy ultra-sonication was used for the preparation of P-NE. The developed nanoemulsion (NE) was characterized using different analytical methods. Field emission transmission electron microscopy (FE-TEM) analyzed the spherical shape and morphology. In addition, stability was analyzed by Dynamic light scattering (DLS) analysis, where particle size was analyzed 83 nm, and Zeta potential −28.20 ± 2 (mV). Furthermore, 90 days of stability was tested using different temperatures conditions where excellent stability was observed. P-NE are non-toxic in (HaCaT), and RAW264.7 cells up to 100 µg/mL further showed effects on ROS and NO production of the cells at 50 µg/mL. The qPCR analysis demonstrated the suppression of pro-inflammatory mediators for (Cox 2, IL-6, IL-1β, and TNF-α, NF-κB, Ikkα, and iNOS) gene expression. The prepared NE exhibited anti-inflammatory effects, demonstrating its potential as a safe and non-toxic nanomedicine. 相似文献
992.
Vimbainashe E. Manhivi Retha M. Slabbert Dharini Sivakumar 《Molecules (Basel, Switzerland)》2022,27(1)
This study investigated the effect of co-ingesting Natal plums (Carissa macrocarpa) and Marula nuts (Sclerocarya birrea) on the bioaccessibility and uptake of anthocyanins, antioxidant capacity, and the ability to inhibit α-glucosidase. A Natal plum–Marula nut bar was made by mixing the raw nuts and the fruit pulp in a ratio 1:1 (v/v). The cyanidin-3-O-sambubioside (Cy-3-Sa) and cyanidin-3-O-glucoside content (Cy-3-G) were quantified using the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS). Inclusion of Natal plum in the Marula nut bar increased the Cy-3-Sa, Cy-3-G content, antioxidants capacity and α-glucosidase inhibition compared to ingesting Marula nut separately at the internal phase. Adding Natal plum to the Marula nut bar increased bioaccessibility of Cy-3-Sa, Cy-3-G, quercetin, coumaric acid, syringic acid and ferulic acid to 80.2% and 71.9%, 98.7%, 95.2%, 51.9% and 89.3%, respectively, compared to ingesting the Natal plum fruit or nut separately. 相似文献
993.
T. Matulewicz L. Aphecetche Y. Charbonnier H. Delagrange K.K. Gudima G. Martınez M. Płoszajczak Y. Schutz V.D. Toneev M. Appenheimer R. Averbeck J. Dıaz A. Döppenschmidt M.J. van Goethem S. Hlavač M. Hoefman R. Holzmann F. Lefèvre A. Kugler H. Löhner A. Marın V. Metag R. Novotny R.W. Ostendorf R.H. Siemssen R.S. Simon R. Stratmann H. Ströher P. Tlusty P.H. Vogt V. Wagner J. Weiss H.W. Wilschut F. Wissmann A.R. Wolf M. Wolf 《The European Physical Journal A - Hadrons and Nuclei》2000,9(1):69-72
Proton-π0 coincidences have been measured at the beam energy of 180A MeV in the reaction Ar+Ca studied by TAPS at SIS/GSI. In the proton-π0 invariant mass spectrum we observe a significant excess of strength above the background obtained by event mixing. We attribute
this signal to the strength distribution N
Δ of the Δ baryonic resonance. No correlation is observed in the case of deuteron-π0 coincidences. Assuming isotropic emission of π0 and Δ+ from a midrapidity thermal source and isospin symmetry, we determined the global N
Δ/N
πratio of 0.79 ±0.30(stat) ±0.2(syst). This value indicates that most pions produced at subthreshold energy in heavy-ion reaction
are mediated by the Δ-resonance.
Received: 7 April 2000 / Accepted: 29 August 2000 相似文献
994.
J. Hüfner Yu.P. Ivanov B.Z. Kopeliovich J. Raufeisen 《The European Physical Journal A - Hadrons and Nuclei》2000,7(3):391-396
The mass spectrum is calculated for those dileptons which are produced in the early phase of a heavy ion collisions via the
direct production NN → l+l−X and via the Compton process GN → l+l−X with prompt gluons radiated in preceding NN interactions. Both mechanisms produce a mass spectrum which decreases steeply
with invariant mass of the l+l− pair and which is below the CERES data for Pb-Au collisions by about one order of magnitude.
Received: 1 December 1999 / Revised version: 18 February 2000 相似文献
995.
The interaction of an η-meson with two nucleons is studied within a three-body approach. The major features of the ηNN-system in the low-energy region are accounted for by using a s-wave separable ansatz for the two-body ηN and NN amplitudes. The calculation is confined to the (J
π;T) = (0-;1) and (1-;0) configurations which are assumed to be the most promising candidates for virtual or resonant ηNN-states. The eigenvalue three-body equation is continued analytically into the nonphysical sheets by contour deformation.
The position of the poles of the three-body scattering matrix as a function of the ηN-interaction strength is investigated. The corresponding trajectory, starting on the physical sheet, moves around the ηNN three-body threshold and continues away from the physical area giving rise to virtual ηNN-states. The search for poles on the nonphysical sheets adjacent directly to the upper rim of the real energy axis gives a
negative result. Thus no low-lying s-wave ηNN-resonances were found. The possible influence of virtual poles on the low-energy ηNN-scattering is discussed.
Received: 27 June 2000 / Accepted: 3 August 2000 相似文献
996.
Emergy Based Analysis of Italian Electricity Production System 总被引:3,自引:0,他引:3
Caruso C. Catenacci G. Marchettini N. Principi I. Tiezzi E. 《Journal of Thermal Analysis and Calorimetry》2001,66(1):265-272
The continuously increasing demand for electric power together with the demand of environmental friendly technologies require
a deep acknowledgement of the directions to give to electric power production in order to satisfy both necessities.
The aim of this work is to evaluate the sustainability of Italian electric system by using the emergy function, a methodology
developed in the early80s by Odum, and its correlated indices. Emergy is a thermodynamic based function that calculates all
the fluxes of energy requested to obtain a product going backward to the solar energy invested.
We analyzed all the inputs concurring to the yield of electricity taking into account not only the final phases of the production
but also all the sources and materials that had been necessary for the system to operate. We have performed a wide analysis
of all the different types of production focusing on thermoelectric sector.
We have obtained not only a thermodynamic analysis of electricity production but also an evaluation of the sustainability
of the entire process and a scenario for a correct exploitation of resources.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
997.
应用电位滴定法测量了烷基巯基四氮茚等一系列感光乳剂稳定剂的银盐溶度积和酸离解常数,其中有些化合物的常数属首次报道;所得数据表明:含巯基的四氮茚的银盐溶解度小于4-羟基-1,3,3a,7-四氮茚类化合物.同时应用Harmmett方程考察了感光乳剂稳定剂或防灰雾剂的性质,结果表明:从苯衍生物导出的σ值也可应用于预测杂环化合物的某些特性. 相似文献
998.
ABSTRACT. We use mechanistic arguments to generalize a hierarchical metaphysiological approach developed by one of us to modeling biological populations (Getz, [1991, 1993]) and extend the approach to include a storage component in the population. We model the growth of single species and consumer-resource interactions, both with and without storage. Our approach unifies modeling storage across trophic levels and is much simpler and more efficient to implement numerically than individual based approaches or population approaches that include integral, delay, or partial differential equation components in the model. Using intake functions (i.e., functional responses) that include the effects of interference competition, we apply the model to a hypothetical herbivore feeding on a resource that fluctuates seasonally and demonstrate the importance of a flow from storage that buffers the population against periods when resources are scarce or absent. We also apply the model to a hypothetical plant population that is driven by fluctuating resources and demonstrate the importance of a translocation flow from storage at the end of a dormant season, corresponding to periods when resources are most scarce. Finally, we couple these two populations for the case where the herbivore feeds exclusively on non-storage biomass, and demonstrate how the population dynamics can be affected by the rates at which buffering and translocation flows transfer from storage to active tissue in the herbivore and plant populations. In particular, for certain buffering and translocation flow rates, 1-year unimodal, 2-year bimodal, and 2-year unimodal cycles can emerge in the same herbivore population. 相似文献
999.
Comparison of different methods for the detoxification of lignocellulose hydrolyzates of spruce 总被引:9,自引:0,他引:9
Simona Larsson Anders Reimann Nils-Olof Nilvebrant Leif J. Jönsson 《Applied biochemistry and biotechnology》1999,77(1-3):91-103
This study describes different detoxification methods to improve both cell growth and ethanol production by Baker's yeast,
Saccharomyces cerevisiae. A dilute-acid hydrolyzate of spruce was used for the all detoxification methods tested. The changes in the concentrations
of fermentable sugars and three groups of inhibitory compounds—aliphatic acids, furan derivatives, and phenolic compounds—were
determined and the fermentability of the detoxified hydrolyzate was assayed. The applied detoxification methods included:
treatment with alkali (sodium hydroxide or calcium hydroxide); treatment with sulfite (0.1% [w/v] or 1% [w/v] at pH 5.5 or
10); evaporation of 10% or 90% of the initial volume; anion exchange (at pH 5.5 or 10); enzymatic detoxification with the
phenoloxidase laccase; and detoxification with the filamentous fungus Trichoderma reesei. An ion exchange at pH 5.5 or 10, treatment with laccase, treatment with calcium hydroxide, and treatment with T. reesei were the most efficient detoxification methods. Evaporation of 10% of the initial volume and treatment with 0.1% sulfite
were the least efficient detoxification methods. Treatment with laccase was the only detoxification method that specifically
removed only one group of the inhibitors, namely phenolic compounds. Anion exchange at pH 10 was the most efficient method
for removing all three major groups of inhibitory compounds; however, it also resulted in loss of fermentable sugars. 相似文献
1000.
生产函数中参数估计方法的改进 总被引:2,自引:0,他引:2
在原有生产函数参数估计方法的基础上,提出一种新的估计方法。计算实例表明:该估计方法具有最小的残差平方和,是一种比较理想的估计方法 相似文献