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911.
May Nasser Bin-Jumah Muhammad Shahid Nadeem Sadaf Jamal Gilani Fahad A. Al-Abbasi Inam Ullah Sami I. Alzarea Mohammed M. Ghoneim Sultan Alshehri Aziz Uddin Bibi Nazia Murtaza Imran Kazmi 《International journal of molecular sciences》2022,23(3)
Aging is a complex process indicated by low energy levels, declined physiological activity, stress induced loss of homeostasis leading to the risk of diseases and mortality. Recent developments in medical sciences and an increased availability of nutritional requirements has significantly increased the average human lifespan worldwide. Several environmental and physiological factors contribute to the aging process. However, about 40% human life expectancy is inherited among generations, many lifespan associated genes, genetic mechanisms and pathways have been demonstrated during last decades. In the present review, we have evaluated many human genes and their non-human orthologs established for their role in the regulation of lifespan. The study has included more than fifty genes reported in the literature for their contributions to the longevity of life. Intact genomic DNA is essential for the life activities at the level of cell, tissue, and organ. Nucleic acids are vulnerable to oxidative stress, chemotherapies, and exposure to radiations. Efficient DNA repair mechanisms are essential for the maintenance of genomic integrity, damaged DNA is not replicated and transferred to next generations rather the presence of deleterious DNA initiates signaling cascades leading to the cell cycle arrest or apoptosis. DNA modifications, DNA methylation, histone methylation, histone acetylation and DNA damage can eventually lead towards apoptosis. The importance of calorie restriction therapy in the extension of lifespan has also been discussed. The role of pathways involved in the regulation of lifespan such as DAF-16/FOXO (forkhead box protein O1), TOR and JNK pathways has also been particularized. The study provides an updated account of genetic factors associated with the extended lifespan and their interactive contributory role with cellular pathways. 相似文献
912.
Lara L. Reys Vijayaganapathy Vaithilingam Mireille M. J. P. E. Sthijns Eduardo Soares Timo Rademakers Rick de Vries Sami G. Mohammed Denise de Bont Marlon J. Jetten Carolin Hermanns Omar Paulino da Silva Filho Adam Stell Nizar I. Mourad Pierre Gianello Vanessa L. S. LaPointe Simone S. Silva Rui L. Reis Tiago H. Silva Aart A. van Apeldoorn 《Advanced functional materials》2021,31(35):2011205
Microencapsulating pancreatic islets in immunoprotective alginate hydrogels is a promising strategy for treatment of type 1 diabetes. However, this strategy is limited by inflammation and hypoxia mediated oxidative stress, due to encapsulation and the hydrogel itself, leading to impaired insulin secretion and limited short and long term cell survival. Herein, the antioxidant effect of fucoidan, an algae derived polysaccharide, on beta cells, and its positive effects on encapsulated beta cell viability and function is presented. Fucoidan from Fucus vesiculosus (FF) exhibits a high total antioxidant capacity, and free radical scavenging activity, and is able to significantly alleviate intracellular oxidative stress in rat insolinoma beta cells (INS1E). In addition, FF significantly increases insulin secretion in a dose- and time-dependent manner. When FF is incorporated in ultrapure alginate used for microencapsulation of primary rat islets, both viability and glucose responsiveness of rat islets in these socalled Fucogel microcapsules (Fucocaps) are found to be significantly higher compared to islets encapsulated in alginate alone. Similar results are obtained with INS1E pseudoislets and neonatal pig islets. Fucocaps can provide a redox-modulatory niche and an immune barrier for islets and beta cells in the same time leading to significantly improved survival and endocrine function by mitigating oxidative stress. 相似文献
913.
Ayman M Atta Sami A Al‐Hussain Hamad A Al‐Lohedan Abdelrhman O Ezzat Ahmed M Tawfeek Talal Al‐Otabi 《Polymer International》2018,67(4):471-480
In situ techniques have attracted great attention for the formation of nanomaterials with controlled sizes, shapes and dispersion within supramolecular hydrogels. In the present work, the doping of copper oxides onto magnetite nanoparticles into hydrogels based on sodium 2‐acylamido‐2‐methylpropanesulfonate (AMPS) and N‐isopropylacrylamide NIPAm copolymers was investigated. The contents, morphology and thermal stability of magnetite, cupreous oxide and doped copper oxides onto the magnetite nanoparticles were evaluated. The optimum conditions for removal the cationic dye methylene blue (MB), such as solution pH, concentration of adsorbents, contact time and stirring time, were determined to investigate the effect of MB concentrations on the removal efficiencies of the prepared adsorbents. The recyclability of the prepared AMPS/NIPAm composites for the removal of MB was examined for up to six cycles without changes in removal effectiveness. © 2018 Society of Chemical Industry 相似文献
914.
Sami Hemdane Pieter J. Jacobs Emmie Dornez Joran Verspreet Jan A. Delcour Christophe M. Courtin 《Comprehensive Reviews in Food Science and Food Safety》2016,15(1):28-42
Wheat bran, a by‐product of the industrial roller milling of wheat, is increasingly added to food products because of its nutritional profile and physiological effects. Epidemiological data and scientific studies have demonstrated the health benefits of consuming bran‐rich or whole‐grain food products. However, incorporation of wheat bran in cereal‐based products negatively affects their production process. Furthermore, the organoleptic quality of the obtained products is mostly perceived as inferior to that of products based on refined wheat flour. This review summarizes the current knowledge on the impact of wheat bran on bread making, provides a comprehensive overview of the bran properties possibly involved, and discusses different strategies that have been evaluated up till now to counteract the detrimental effects of wheat bran on bread making. 相似文献
915.
Soumaya Hamouda Sourour El‐Bessi Sami Tabbane 《International Journal of Communication Systems》2016,29(10):1605-1619
In cognitive radio networks, Secondary Users (SUs) can access the spectrum simultaneously with the Primary Users (PUs) in underlay mode. In this case, interference caused to the licensed users has to be effectively controlled. The SUs have to make spectrum access decisions in order to enhance their quality of service, but without causing harmful interference to the coexisting PUs. In this paper, we propose a cooperative spectrum decision, which enables the SUs to share the spectrum with the PUs more efficiently. Our approach is based on a new coalitional game in which the coalition value is a function of the SUs' spectral efficiencies, the inter‐SUs interference, and the interference caused to the PUs. By applying new Enter and Leave rules, we obtain a stable coalition structure. Simulation results show that the SUs' spectral efficiencies are considerably increased and that the interference caused to the coexisting PU is reduced by about 7.5% as compared to an opportunistic spectrum access scheme. Moreover, the proposed coalitional game results in a more balanced spectrum sharing in the network. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
916.
Sami Saadi;Chaalal Makhlouf;Nor Elhouda Nacer;Boughellout Halima;Adoui Faiza;Hafid Kahina;Falek Wahiba;Kheroufi Afaf;Kezih Rabah;Zineddine Saoudi; 《Comprehensive Reviews in Food Science and Food Safety》2024,23(1):e13288
Whey protein derived bioactives, including α-lactalbumin, ß-lactoglobulin, bovine serum albumin, lactoferrin, transferrin, and proteose–peptones, have exhibited wide ranges of functional, biological and therapeutic properties varying from anticancer, antihypertensive, and antimicrobial effects. In addition, their functional properties involve gelling, emulsifying, and foaming abilities. For these reasons, this review article is framed to understand the relationship existed in between those compound levels and structures with their main functional, biological, and therapeutic properties exhibited either in vitro or in vivo. The impacts of hydrolysis mechanism and separation techniques in enhancing those properties are likewise discussed. Furthermore, special emphasize is given to multifunctional effects of whey derived bioactives and their future trends in ameliorating further food, pharmaceutical, and nutraceutical products. The underlying mechanism effects of those properties are still remained unclear in terms of activity levels, efficacy, and targeted effectiveness. For these reasons, some important models linking to functional properties, thermal properties and cell circumstances are established. Moreover, the coexistence of radical trapping groups, chelating groups, sulfhydryl groups, inhibitory groups, and peptide bonds seemed to be the key elements in triggering those functions and properties. 相似文献
917.
Muhammad Asif Javed;Abuzar Ghaffari;Ahmed S. Sowayan;H. M. Atif;Sami Ullah Khan; 《Polymer Engineering and Science》2024,64(7):3088-3100
The blade coating is an essential industrial technique that involves applying a protective liquid layer to a moving surface with a smoothing blade. In this article we demonstrated the non-isothermal analysis of blade coating using viscoelastic fluid model numerically. The flow equations are made simplify using lubrication approximation theory (LAT). The resulting dimensionless flow and energy equations are simulated using a robust fourth-order Runge–Kutta and Newton–Raphson methods to calculate the coating thickness (), stream function, velocity pressure, temperature profile, pressure gradient and blade load. The impact of the slip and involved parameters on these quantities are deliberated through various graphs and tables. The temperature distribution increases as the Brinkman number rises, with the maximum temperature occurring in the nip region of the flow. The mechanical quantities such as coating thickness increases while the blade load decreases with increasing the values of the slip parameter as compared with Newtonian model for both plane and exponential coater. 相似文献
918.
Bekir Sami Yilbas Aditya Kumar Bharat Bhushan B. J. Abdul Aleem 《Journal of Thermal Spray Technology》2014,23(7):1210-1224
Laser treatment under nitrogen assisting gas environment of cobalt-nickel-chromium-tungsten-based superalloy and high-velocity oxygen-fuel thermal spray coating of nickel-chromium-based superalloy on carbon steel was carried out to improve mechanical and tribological properties. Superalloy surface was preprepared to include B4C particles at the surface prior to the laser treatment process. Material and morphological changes in the laser-treated samples were examined using scanning electron microscopy, energy-dispersive spectroscopy, and x-ray diffraction (XRD) analysis. Residual stresses present at the surface region of the laser-treated layer were determined from the XRD data. The microhardness of the laser-treated surface was measured by indentation tests. Fracture toughness of the coating surfaces before and after laser treatment were also measured using overload indentation tests. Macrowear and macrofriction characterization were carried out using pin-on-disk tests. 相似文献
919.
Sobia Nawaz Sidra Rasheed Wania Sami Lal Hussain Amjad Aldweesh Elsayed Tag eldin Umair Ahmad Salaria Mohammad Shahbaz Khan 《计算机、材料和连续体（英文）》2023,75(3):5213-5228
This study is designed to develop Artificial Intelligence (AI) based analysis tool that could accurately detect COVID-19 lung infections based on portable chest x-rays (CXRs). The frontline physicians and radiologists suffer from grand challenges for COVID-19 pandemic due to the suboptimal image quality and the large volume of CXRs. In this study, AI-based analysis tools were developed that can precisely classify COVID-19 lung infection. Publicly available datasets of COVID-19 (N = 1525), non-COVID-19 normal (N = 1525), viral pneumonia (N = 1342) and bacterial pneumonia (N = 2521) from the Italian Society of Medical and Interventional Radiology (SIRM), Radiopaedia, The Cancer Imaging Archive (TCIA) and Kaggle repositories were taken. A multi-approach utilizing deep learning ResNet101 with and without hyperparameters optimization was employed. Additionally, the features extracted from the average pooling layer of ResNet101 were used as input to machine learning (ML) algorithms, which twice trained the learning algorithms. The ResNet101 with optimized parameters yielded improved performance to default parameters. The extracted features from ResNet101 are fed to the k-nearest neighbor (KNN) and support vector machine (SVM) yielded the highest 3-class classification performance of 99.86% and 99.46%, respectively. The results indicate that the proposed approach can be better utilized for improving the accuracy and diagnostic efficiency of CXRs. The proposed deep learning model has the potential to improve further the efficiency of the healthcare systems for proper diagnosis and prognosis of COVID-19 lung infection. 相似文献
920.
Nidhi Agarwal M. Gokilavani S. Nagarajan S. Saranya Hadeel Alsolai Sami Dhahbi Amira Sayed Abdelaziz 《计算机、材料和连续体（英文）》2023,74(1):141-152
In recent times, wireless sensor network (WSN) finds their suitability in several application areas, ranging from military to commercial ones. Since nodes in WSN are placed arbitrarily in the target field, node localization (NL) becomes essential where the positioning of the nodes can be determined by the aid of anchor nodes. The goal of any NL scheme is to improve the localization accuracy and reduce the localization error rate. With this motivation, this study focuses on the design of Intelligent Aquila Optimization Algorithm Based Node Localization Scheme (IAOAB-NLS) for WSN. The presented IAOAB-NLS model makes use of anchor nodes to determine proper positioning of the nodes. In addition, the IAOAB-NLS model is stimulated by the behaviour of Aquila. The IAOAB-NLS model has the ability to accomplish proper coordinate points of the nodes in the network. For guaranteeing the proficient NL process of the IAOAB-NLS model, widespread experimentation takes place to assure the betterment of the IAOAB-NLS model. The resultant values reported the effectual outcome of the IAOAB-NLS model irrespective of changing parameters in the network. 相似文献