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991.
Aliyu Idris Muhammad Xinyu Liao Patrick J. Cullen Donghong Liu Qisen Xiang Jun Wang Shiguo Chen Xingqian Ye Tian Ding 《Comprehensive Reviews in Food Science and Food Safety》2018,17(5):1379-1394
Understanding the impact of nonthermal plasma (NTP) technology on key nutritional and functional food components is of paramount importance for the successful adoption of the technology by industry. NTP technology (NTPT) has demonstrated marked antimicrobial efficacies with good retention of important physical, chemical, sensory, and nutritional parameters for an array of food products. This paper presents the influence of NTPT on selected functional food components with a focus on low‐molecular‐weight bioactive compounds and vitamins. We discuss the mechanisms of bioactive compound alteration by plasma‐reactive species and classify their influence on vitamins and their antioxidant capacities. The impact of NTP on specific bioactive compounds depends both on plasma properties and the food matrix. Induced changes are mainly associated with oxidative degradation and cleavage of double bonds in organic compounds. The effects reported to date are mainly time‐dependent increases in the concentrations of polyphenols, vitamin C, or increases in antioxidant activity. Also, improvement in the extraction efficiency of polyphenols is observed. The review highlights future research needs regarding the complex mechanisms of interaction with plasma species. NTP is a novel technology that can both negatively and positively affect the functional components in food. 相似文献
992.
Shehu Muhammad Auwal Mohammad Zarei Chin Ping Tan 《International Journal of Food Properties》2018,21(1):1646-1660
Liposomes are used as effective nanodelivery devices to improve the physicochemical stability and biological efficacy of the encapsulated peptides and proteins. In this study, nanoliposome composite of lipoid S75-entrapped angiotensin I-converting enzyme (ACE)-inhibitory biopeptides was prepared by conventional (BLS75-CM) and direct heating (BLS75-DHM) methods. The nanoliposomes (BLS75-CM and BLS75-DHM) were stored at 4°C for 8 weeks and evaluated for physicochemical stability in terms of particle size, polydispersity index (pdi), zeta potential, and encapsulation efficiency (EE). These were also studied for residual ACE-inhibitory efficacy following their digestion under simulated gastrointestinal tract condition. The BLS75-CM was found to maintain higher physicochemical stability in terms of particle size, pdi, and zeta potential compared to BLS75-DHM. However, the BLS75-DHM indicated higher EE and efficacy with greater residual ACE-inhibitory activity of 47.37% compared to 44.18% and 36.84% that were obtained for the digested BLS75-CM and digested biopeptides without encapsulation, respectively. In vitro release study showed a cumulative biopeptides release of 66.41% and 69.00% from BLS75-CM and BLS75-DHM, respectively. The results of transmission electron microscopy showed spherical appearance of the nanoliposome capsules while Fourier Transform Infrared spectroscopy indicated the presence of ionic complexation and hydrogen bonds between the biopeptides and their phospholipid matrix. 相似文献
993.
This communique is opted to study the approximate solution of the Algebraic Lyapunov equation on the manifold of positive-definite Hermitian matrices. We choose the geodesic distance between -AHX - XA and P as the cost function, and put forward the Extended Hamiltonian algorithm (EHA) and Natural gradient algorithm (NGA) for the solution. Finally, several numerical experiments give you an idea about the effectiveness of the proposed algorithms. We also show the comparison between these two algorithms EHA and NGA. Obtained results are provided and analyzed graphically. We also conclude that the extended Hamiltonian algorithm has better convergence speed than the natural gradient algorithm, whereas the trajectory of the solution matrix is optimal in case of Natural gradient algorithm (NGA) as compared to Extended Hamiltonian Algorithm (EHA). The aim of this paper is to show that the Extended Hamiltonian algorithm (EHA) has superior convergence properties as compared to Natural gradient algorithm (NGA). Upto the best of author’s knowledge, no approximate solution of the Algebraic Lyapunov equation on the manifold of positive-definite Hermitian matrices is found so far in the literature. 相似文献
994.
In this paper, we propose a novel coverless image steganographic scheme based on a generative model. In our scheme, the secret image is first fed to the generative model database, to generate a meaning-normal and independent image different from the secret image. The generated image is then transmitted to the receiver and fed to the generative model database to generate another image visually the same as the secret image. Thus, we only need to transmit the meaning-normal image which is not related to the secret image, and we can achieve the same effect as the transmission of the secret image. This is the first time to propose the coverless image information steganographic scheme based on generative model, compared with the traditional image steganography. The transmitted image is not embedded with any information of the secret image in this method, therefore, can effectively resist steganalysis tools. Experimental results show that our scheme has high capacity, security and reliability. 相似文献
995.
Enzymolysis reaction kinetics and thermodynamics of rapeseed protein with sequential dual‐frequency ultrasound pretreatment 下载免费PDF全文
Asif Wali Haile Ma Khizar Hayat Xiaofeng Ren Zeshan Ali Yuqing Duan Muhammad Tayyab Rashid 《International Journal of Food Science & Technology》2018,53(1):72-80
We evaluated the effect of sequential dual‐frequency ultrasound (SDFU) pretreatments on rapeseed protein enzymolysis, using alcalase as a model enzyme. Hydrolysed protein concentrations, enzymolysis kinetics and thermodynamic parameters were investigated. The results showed that the hydrolysed rapeseed protein concentration following SDFU pretreatments was higher compared to that of the control for up to 75 min of enzymolysis at various substrate concentrations of 5–25 g L?1; both control and SDFU pretreatment groups showed first‐order reaction kinetics. Compared to the control, the Michaelis–Menten constant (KM) value decreased remarkably by 17.61%, while an increase in the binding frequency between enzyme and substrate (KA) by 10.47% was observed. The thermodynamic parameters, enthalpy, entropy and activation energy were reduced in the SDFU pretreatment group compared to the control by 31.78%, 18.0% and 29.56%, respectively. SDFU pretreatment showed little effect on Gibbs free energy at the various temperatures studied. 相似文献
996.
Metallurgical and Materials Transactions B - This study provides the thermodynamic properties of the Mg-B binary alloys. Experiments were performed to measure the electromotive force (emf) as a... 相似文献
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999.
Adnan AHMED Kamalrulnizam ABU BAKAR Muhammad Ibrahim CHANNA Khalid HASEEB Abdul Waheed KHAN 《Frontiers of Computer Science》2015,9(2):280
Mobile ad-hoc networks (MANETs) and wireless sensor networks (WSNs) have gained remarkable appreciation and technological development over the last few years. Despite ease of deployment, tremendous applications and significant advantages, security has always been a challenging issue due to the nature of environments in which nodes operate. Nodes’ physical capture, malicious or selfish behavior cannot be detected by traditional security schemes. Trust and reputation based approaches have gained global recognition in providing additional means of security for decision making in sensor and ad-hoc networks. This paper provides an extensive literature review of trust and reputation based models both in sensor and ad-hoc networks. Based on the mechanism of trust establishment, we categorize the stateof-the-art into two groups namely node-centric trust models and system-centric trust models. Based on trust evidence, initialization, computation, propagation and weight assignments, we evaluate the efficacy of the existing schemes. Finally, we conclude our discussion with identification of some unresolved issues in pursuit of trust and reputation management. 相似文献
1000.
Muhammad Arifur Rahman Ravinder Kumar Enrique Sanchez Taras Y. Nazarko 《International journal of molecular sciences》2021,22(15)
Although once perceived as inert structures that merely serve for lipid storage, lipid droplets (LDs) have proven to be the dynamic organelles that hold many cellular functions. The LDs’ basic structure of a hydrophobic core consisting of neutral lipids and enclosed in a phospholipid monolayer allows for quick lipid accessibility for intracellular energy and membrane production. Whereas formed at the peripheral and perinuclear endoplasmic reticulum, LDs are degraded either in the cytosol by lipolysis or in the vacuoles/lysosomes by autophagy. Autophagy is a regulated breakdown of dysfunctional, damaged, or surplus cellular components. The selective autophagy of LDs is called lipophagy. Here, we review LDs and their degradation by lipophagy in yeast, which proceeds via the micrometer-scale raft-like lipid domains in the vacuolar membrane. These vacuolar microdomains form during nutrient deprivation and facilitate internalization of LDs via the vacuolar membrane invagination and scission. The resultant intra-vacuolar autophagic bodies with LDs inside are broken down by vacuolar lipases and proteases. This type of lipophagy is called microlipophagy as it resembles microautophagy, the type of autophagy when substrates are sequestered right at the surface of a lytic compartment. Yeast microlipophagy via the raft-like vacuolar microdomains is a great model system to study the role of lipid domains in microautophagic pathways. 相似文献