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1.
Enzyme-assisted extraction (EAE) of oils/fats involves the disruption of the cell wall of source material using enzymes to facilitate the release of oil. When proteases are used as the enzyme, EAE ends in the extracted oil as well as the protein hydrolysates. Herein, the EAE (using a commercial protease, Alcalase) was exploited to obtain fat and protein hydrolysates from chicken skin. Degree of hydrolysis (DH, the percentage ratio of cleaved peptide bonds), which showed a logarithmic correlation with the reaction time, was found to affect the properties of the products. As the DH increased, the peptide chain length of protein hydrolysates decreased which was confirmed by SDS-PAGE analysis. With the increase of DH, the emulsifying activity index, foaming capacity, and oil holding capacity of the hydrolysates decreased but the solubility and emulsion stability index increased (p < 0.05). The DPPH free radical scavenging activity of the hydrolysates increased with the DH up to DH = 39.62% but decreased thereafter (p < 0.05). EAE resulted in a rise in fat yield and the fat contained a higher amount of unsaponifiables and lower free fatty acids (FFA) content, as compared to the control treatment (No enzyme, 80°C, 2 h, p < 0.05). DH affected the fat yield and the unsaponifiables content of the fat, positively (p < 0.05). However, it did not affect the fat FFA content and iodine value (p > 0.05). Results obtained here showed DH can be used as an effective measure for controlling the physicochemical and functional properties of chicken skin protein hydrolysates and fat in the EAE process.  相似文献   
2.
Yupapin  Preecha  Mahesha  C. R.  Fouladi  Hadis  Hamidi  Abdolsamad  Farmani  Ali 《SILICON》2022,14(15):9275-9281
Silicon - The development of advanced materials has attracted interest for promising novel applications in biosensing and realm of nanophotonics. This interest in nanoelectronics, and...  相似文献   
3.
This paper presents management of groundwater resource using a Bayesian Decision Network (BDN). The Kordkooy region in North East of Iran has been selected as study area. The region has been sub-divided into three zones based on transmissivity (T) and electrical conductivity (EC) values. The BDN parameters: prior probabilities and Conditional Probability Tables - CPTs) have been identified for each of the three zones. Three groups of management scenarios have been developed based on the two decision variables including “Crop pattern” and “Domestic water demand” across the three zones of the study area: 1) status quo management for all three zones represent current conditions; 2) the effect of change in cropping pattern on management endpoints and 3) the effect of future increased domestic water demand on management endpoints. The outcomes arising from implementing each scenario have been predicted by use of the constructed BDN for each of the zones. Results reveal that probability of drawdown in groundwater levels of southern areas is relatively high compared with other zones. Groundwater withdrawal from northern and northwestern areas of the study area should be limited due to the groundwater quality problems associated with shallow groundwater of these two zones. The ability of the Bayesian Decision Network to take into account key uncertainties in natural resources and perform meaningful analysis in cases where there is not a vast amount of information and observed data available – and opportunities for enabling inputs for the analysis based partly on expert elicitation,emphasizes key advantages of this approach for groundwater management and addressing the groundwater related problems in a data-scarce area.  相似文献   
4.
Inflammatory bowel diseases (IBDs) are immune-mediated, chronic relapsing diseases with a rising prevalence worldwide in both adult and pediatric populations. Treatment options for immune-mediated diseases, including IBDs, are traditional steroids, immunomodulators, and biologics, none of which are capable of inducing long-lasting remission in all patients. Dendritic cells (DCs) play a fundamental role in inducing tolerance and regulating T cells and their tolerogenic functions. Hence, modulation of intestinal mucosal immunity by DCs could provide a novel, additional tool for the treatment of IBD. Recent evidence indicates that probiotic bacteria might impact immunomodulation both in vitro and in vivo by regulating DCs’ maturation and producing tolerogenic DCs (tolDCs) which, in turn, might dampen inflammation. In this review, we will discuss this evidence and the mechanisms of action of probiotics and their metabolites in inducing tolDCs in IBDs and some conditions associated with them.  相似文献   
5.
In this study (1 − x) K0.48Na0.48Li0.04Nb0.96Ta0.04O3 − xSrTiO3 (0.0 ≤ x ≤ 0.10) ceramics were fabricated by sintering in microwave furnace for first time as well as in conventional furnace (either via single step or two-step procedures). Sintering behavior and piezoelectric properties of sintered samples were studied and compared. It was found that two-step sintering decreases sintering temperature effectively and enhances densification compared to single step sintering. Microstructure analysis revealed that, two-step sintering suppresses grain growth and promotes densification. On the other hand, microwave sintering enhanced densification more effectively and reduced sintering time and temperature. The maximum piezoelectric constants of ceramics were measured for those sintered in microwave furnace. Piezoelectric constant of the sample containing 1 mol% SrTiO3 which was sintered in microwave furnace was measured 310 pC N−1 while by sintering in conventional furnace via single and two-step sintering it was obtained 208 and 278 pC N−1, respectively.  相似文献   
6.

Processes such as growth and atrophy cause changes through time that can be visible in a series of medical images, following the hypothesis that form follows function. As was hypothesised by D’Arcy Thompson more than 100 years ago, models of the changes inherent in these actions can aid understanding of the processes at work. We consider how image registration using finite-dimensional planar Lie groups (in contrast to general diffeomorphisms) can be used in this process. The deformations identified can be described as points in the Lie algebra, thus enabling processes such as evolutionary change, growth, and deformation from disease, to be described in a linear space. The choice of appropriate Lie group becomes a modelling choice and can be selected using model selection; Occam’s razor suggests that groups with the smallest number of parameters (which Thompson referred to as ‘simple transformations’) are to be preferred. We demonstrate our method on an example from Thompson of the cannon-bones of three hoofed mammals and a set of outline curves of the development of the human skull, with promising results.

  相似文献   
7.
The simplest and the most cost-effective way of human milk fat substitute (HMFS) production is formulating of suitable vegetable oils at proper ratios. To do this, the D-optimal mixture design was used to optimize the HMFS formulation. The design included 25 formulations made from refined palm olein (35–55%), soybean oil (5–25%), olive oil (5–20%), virgin coconut oil (5–15%), and fish oil (0–10%). Samples were produced in laboratory and characterized in terms of fatty acid and triacylglycerol (TAG) compositions, free fatty acid content, peroxide value, iodine value, and oxidative stability index (OSI). HMFS samples were also compared with Codex Alimentarius (CA) and Iran National Standards Organization (INSO) standards. Each characteristic of HMFS samples was then expressed as a function of ingredient ratio using regression models. Finally, using numerical optimization, four optimized blends (PB1-PB4) were selected, made in the laboratory (HMFS1-HMFS4), characterized, and compared with CA and INSO standards. The properties of all the optimized blends (except the palmitic acid content of HMFS2 and the monounsaturated fatty acid [MUFA] content of HMFS3) met the standards. HMFS4 showed the highest OSI in Rancimat and the lowest oxidation rate in Schaal oven tests. POL (19.53–21.73%), PPO (20.77–21.73%), OOO (9.11–11.16%), and OPO (8.84–9.46%) were the main (totally about 60%) TAG species found in HMFS samples. In conclusion, the HMFS4 formula (55% palm olein, 13.5% soybean oil, 16% refined olive oil, 15% virgin coconut oil, and 0.5% fish oil) was suggested as the best formula for HMFS production.  相似文献   
8.
Stabilized nickel nanoparticles (SNNPs) were prepared using \(\hbox {Ni(acac)}_{2}\) (\(\hbox {acac} = \hbox {acetylacetonate}\)) via a simple solvothermal method. The synthesis of the nickel nanoparticles was performed in the presence of sodium dodecyl sulphate (SDS) of different concentrations (mole ratios of SDS:\(\hbox {Ni(acac)}_{2} = 1{:}1\), 2:1 and 4:1), as the stabilizer, in order to appraise their influence on the morphology, size, dispersion, magnetic properties and electrochemical activity of the nickel nanoparticles. The synthesized products have been characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectra, energy-dispersive X-ray spectroscopy, vibrating sample magnetometry and electrochemical studies. It is noteworthy that the average particles size of the SNNPs has been reduced by increasing the SDS concentration, while at high concentration (mole ratio of SDS:\(\hbox {Ni(acac)}_{2} = 4{:}1\)), the small particles tend to coalesce and create a big one. The stabilized Ni nanoparticles could be used as electrode materials for hydrogen evolution in alkaline medium. The electrochemical measurements demonstrated that the higher conductivity and lower value of faraday resistance of the as-prepared samples were when the mole ratio of SDS:\(\hbox {Ni(acac)}_{2}\) was 2:1.  相似文献   
9.
10.
ABSTRACT

ZrB2–ZrC–SiC is one of the ultra-high-temperature ceramic composites with excellent properties. In this research, high-purity ZrB2–ZrC–SiC nanopowders were synthesised using a carbothermal reduction reaction at a relatively low temperature (1370°C) from cost-effective zirconium(IV) chloride by a sol–gel method. The effect of heat treatment temperature on the synthesis of ZrB2–ZrC–SiC composite powder was studied. X-ray diffractometry results showed that the phases ZrB2, β-SiC and ZrC were synthesised at 1370°C. The mean crystallite sizes for each of the phases were calculated using the Scherrer method. The specific surface area for the sample calcined at 1370°C was 81.479?m2?g?1. SEM observation revealed that the particles had a size lower than 250?nm. Backscattered electron image and map analysis with scanning electron microscopy showed that a suitable phase homogeneity was achieved, as confirmed by energy-dispersive X-ray spectroscopy.  相似文献   
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