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排序方式: 共有1112条查询结果,搜索用时 17 毫秒
871.
Quinoa is a nutrient-dense food that lowers chronic disease risk. This study evaluated the physicochemical and sensory qualities of fermented camel milk with 1, 2, 3, and 4% quinoa. The results showed that improvement in camel’s milk increased the total solids, protein, ash, fiber, phenolic content, and antioxidant activity more effectively. Fermented camel milk with 3% of quinoa flour exhibited the highest sensory characteristics compared to other treatments. Fermented camel milk enriched with 3% red quinoa flour was studied in obese rats. Forty male Wistar rats were separated into five groups: the first group served as a normal control, while groups 2–4 were fed a high-fat, high-cholesterol (HF)-diet and given 2 mL/day of fermented milk and quinoa aqueous extract. Blood glucose, malondialdehyde (MDA), low-density lipoprotein (LDL), cholesterol, triglyceride, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), creatinine, and urea levels decreased dramatically in comparison to the positive control group, while high-density lipoprotein (HDL), albumin, and total protein concentrations increased significantly. Fortified fermented camel milk decreased the number of giant adipocytes while increasing the number of tiny adipocytes in the body. The results showed that the liver and renal functions of hypercholesterolemic rats were enhanced by consuming fermented milk and quinoa. These results demonstrated the ability of quinoa and camel milk to protect rats from oxidative stress and hyperlipidemia. Further studies are needed to clarify the mechanisms behind the metabolic effects of fermented camel milk and quinoa.  相似文献   
872.
This study correlated biomass heat capacity (Cp) with the chemistry (sulfur and ash content), crystallinity index, and temperature of various samples. A five-parameter linear correlation predicted 576 biomass Cp samples from four different origins with the absolute average relative deviation (AARD%) of ~1.1%. The proportional reduction in error (REE) approved that ash and sulfur contents only enlarge the correlation and have little effect on the accuracy. Furthermore, the REE showed that the temperature effect on biomass heat capacity was stronger than on the crystallinity index. Consequently, a new three-parameter correlation utilizing crystallinity index and temperature was developed. This model was more straightforward than the five-parameter correlation and provided better predictions (AARD = 0.98%). The proposed three-parameter correlation predicted the heat capacity of four different biomass classes with residual errors between −0.02 to 0.02 J/g∙K. The literature related biomass Cp to temperature using quadratic and linear correlations, and ignored the effect of the chemistry of the samples. These quadratic and linear correlations predicted the biomass Cp of the available database with an AARD of 39.19% and 1.29%, respectively. Our proposed model was the first work incorporating sample chemistry in biomass Cp estimation.  相似文献   
873.
Studies have shown an inverse correlation among age-related illnesses like coronary heart disease and cancer and intake of fruit and vegetable. Given the probable health benefits of natural antioxidants from plants, research on them has increased. Dactylorhiza osmanica is consumed as a food and traditional medicine plant in some regions of Turkey, so evaluation of the biological ability of this species is important. In this study, the amount of phenolic content (LC-HRMS), antioxidant activities and enzyme inhibitory properties of an endemic plant, D. osmanica, were investigated. The antioxidant capacities of an ethanol extract of D. osmanica aerial parts (EDOA) and roots (EDOR) were evaluated with various antioxidant methods. Additionally, the enzyme inhibitory effects of EDOA and EDOR were examined against acetylcholinesterase (AChE), α-glycosidase, and α-amylase enzymes, which are associated with common and global Alzheimer’s disease and diabetes mellitus. The IC50 values of EDOA against the enzymes were found to be 1.809, 1.098, and 0.726 mg/mL, respectively; and the IC50 values of EDOR against the enzymes were found to be 2.466, 0.442, and 0.415 mg/mL, respectively. Additionally, LC-HRMS analyses revealed p-Coumaric acid as the most plentiful phenolic in both EDOA (541.49 mg/g) and EDOR (559.22 mg/g). Furthermore, the molecular docking interaction of p-coumaric acid, quercitrin, and vanillic acid, which are the most plentiful phenolic compounds in the extracts, with AChE, α-glucosidase, and α-amylase, were evaluated using AutoDock Vina software. The rich phenolic content and the effective antioxidant ability and enzyme inhibition potentials of EDOA and EDOR may support the plant’s widespread food and traditional medicinal uses.  相似文献   
874.
Herein, we report the synthesis of spinel cobalt oxide nanorods (Co3O4 NRs) by a modified co-precipitation approach and examine their larvicidal activity against Culex pipiens. The structure and morphology of the as-prepared Co3O4 NRs were emphasized using X-ray diffraction (XRD), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDAX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It was found that Co3O4 nanostructures have a face-centered spinel cubic crystal structure with a mean crystallite size of 38 nm. These nanostructures have a rod like shape with a mean diameter of 30 nm and an average length of 60 nm. The TGA measurements revealed the high stability of the formed spinel cubic structure at 400 °C. The optical behavior indicates the direct transition of electrons through an optical band gap in the range of 2.92–3.08 eV. These unique chemical and physical properties of Co3O4 NRs enabled them to be employed as a strong agent for killing the C. pipiens. A comparison study was employed between the as-prepared Co3O4 and the entomopathogenic fungus Metarhizium brunneum as a control agent of C. pipiens larvae. The results revealed that the as-prepared nanorods have higher mortality against C. pipiens larvae compared with the well-known M. brunneum.  相似文献   
875.
Herein, two‐shaped cerium oxide nanoparticles (NPs), that is, spherical and cubical, were synthesized through hydrothermal approach by tuning reaction temperatures. The morphology and structural and chemical composition of both samples were characterized by transmission electron microscopy (TEM), high‐resolution TEM (HRTEM), X‐ray diffraction (XRD), and X‐ray photoelectron spectroscopy (XPS), respectively. Both types of NPs were subjected to photodegradation of industrial dye, methylene blue, under dark, sunlight, and UV irradiation, and their recyclability and reusability were also assessed. Besides, the effect of pH, concentration of NPs, and dye on degradability was also analyzed. The cubical‐shaped NPs demonstrated superior degradation of ~70% under UV irradiation than the spherical ones (<50%). The antibacterial activities of both NPs were also examined, and cubical‐shaped NPs were found to exhibit superior antimicrobial potential (zone of inhibition [ZOI]: 25.75 ± 0.25, 18.83 ± 0.76, 15.75 ± 0.66, and 15.75 ± 0.25 mm) in comparison with the spherical ones (ZOI: 19.41 ± 0.94, 14.25 ± 0.66, 12.58 ± 1.01, and 9.91 ± 1.01 nm) for Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus respectively with reduced growth and viable count. This difference in performance may be attributed to the higher surface areas of cubical‐shaped NPs and higher content of oxygen vacancies. The results presented in this study suggest that cubical NPs are excellent candidates for treating industrial wastewater with greater reproducibility. Moreover, they can be used as active growth inhibitors against different microorganisms and thus can be extremely useful in developing medical devices and to design various antimicrobial systems.  相似文献   
876.
Wireless Personal Communications - Higher data rate, increased capacity, higher mobility, lower latency and better quality are the mobile communication prime objectives need to improve in the near...  相似文献   
877.
Journal of Thermal Analysis and Calorimetry - In this paper, the effects of inlet valve closing temperature (TIVC) and exhaust gas recirculation (EGR) on the emissions and the performance of a...  相似文献   
878.
Zahran  E. G.  Arafa  A. A.  Saleh  H. I.  Dessouky  M. I. 《Wireless Networks》2020,26(6):4109-4127

The optimal placement of the RFID readers inaugurates an ongoing research field, namely the RFID network planning (RNP). The main issue in the RNP is to know how many readers have to be used and what is their best distribution that guarantees fulfillment of multiple objectives. The common RNP objectives are the optimal coverage, readers’ interference avoidance, redundant reader elimination, load balance among deployed readers and minimum power losses, which are considered as conflicting objectives that leads the RNP to be an NP-hard problem need to be solved. The contributions in this paper are: firstly, utilizing both the Biogeography based optimization (BBO) and the Hybrid Invasive Weed-Biogeography based optimization (HIW-BBO) as new algorithms have not used before for solving the RNP. Secondly, we proposed a Self Learning (SL) strategy with a mixed BBO Migration (MBBOM) operation to modify the HIW-BBO algorithm in an algorithm called Self Learned Invasive Weed-Mixed Biogeography based optimization (SLIWMBBO). Thirdly, the performance of the proposed SLIWMBBO algorithm is compared to both the HIW-BBO and the Self Adaptive Cuckoo Search (SACS) optimization algorithms according to a set of 13 benchmark functions. The results of this comparison encourage the application of the SLIWMBBO as an optimization algorithm for solving the complex problems. Lastly, the BBO, HIW-BBO and SLIWMBBO optimization algorithms are used for solving three complex RNP instances and compared to the SACS algorithm. Simulation results of the SLIWMBBO are outstanding and demonstrate its superiority over the compared algorithms.

  相似文献   
879.
A series of new metal complexes were synthesized in both bulk and nano size using green methods, starting with the reaction of (E)‐N′‐[(E)‐2‐bromobenzylidene]‐4‐oxo‐4‐(piperidin‐1‐yl)but‐2‐enehydrazide with thiosemicarbazide and different metal halides such as CuI·2H2O, CuCl2·2H2O, CoCl2·2H2O, and ZnCl2·2H2O, and metal nitrate such as Ga(NO3)3·2H2O. Structures of these metal complexes were confirmed using different spectroscopic methods, elemental analysis, electronic spectra, and microanalytical methods (scanning electron microscopy and transmission electron microscopy) for nano complexes. The distorted octahedral geometry for all complexes was suggested based on magnetic moments and electronic spectral studies. The cytotoxic activity of the compounds was investigated against human hepatocellular carcinoma (HepG2) and human colorectal carcinoma (HCT‐116) cell lines. Most tested compounds had higher inhibitory activity than the standard vinblastine drug. Interestingly, the nano‐sized Ga(III) complex 11 was the most potent compound against the two tested cell lines, with 50% inhibitory concentration (IC50) of 2.56 μg/mL for HepG2, compared with the reference drug vinblastine (IC50 15.6 μg/mL), and IC50 4.64 μg/mL for HCT‐116, compared with the standard (IC50 13.9 μg/mL). The bioassay results helped us identify new potent and selective anticancer agents.  相似文献   
880.
Journal of Communications Technology and Electronics - This paper recovers soliton solutions to perturbed pure–cubic complex Ginzburg–Landau equation having a dozen forms of nonlinear...  相似文献   
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