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551.
Muhammad Jaseemuddin Junaid Ahmed Zubairi Omer Mahmoud 《Wireless Communications and Mobile Computing》2002,2(4):339-356
There is a growing interest in providing Internet services to the mobile nodes. When mobile nodes travel from one router's service area to another, the time‐sensitive applications may see degradation in service. We investigate into the effects of handoff on service quality of mobile nodes. Several experiments are conducted using various packet metering and marking schemes with or without transferring profiles to the new router. Results indicate the relative instability period following handoff, loss of packets and delay encountered by packets in profiled or un‐profiled handoffs, leading to determining suitable mix of metering and marking schemes with or without context transfer. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
552.
Dr. Alechania Misturini Omer F. Altundal Pablo García-Aznar Sara Kariminasab Dr. German Sastre 《化学,工程师,技术》2023,95(11):1768-1776
Intracrystalline zeolite silanol defect groups (≡SiOH) were modelled in silicalite (silica ZSM-5, MFI) using experimental data. We make a molecular dynamics study on the self-diffusivity of benzene in silicalite with defects. The simulations at three different loadings (1, 3 and 5 benzene per unit cell) and temperatures (298, 348 and 398 K) allow to calculate self-diffusivity, adsorption energy and the activation energy. The results show that benzene self-diffusivity in silicalite is increased by the presence of silanol defects. Previous experimental results support this claim. 相似文献
553.
Nadeem Sayyed Abdul Hafeez Fahad A. Al-Abbasi Asma B Omer Shareefa A. AlGhamdi Amira M. Alghamdi Rayan A. Sheikh Imran Kazmi 《European Journal of Lipid Science and Technology》2023,125(9):2200205
Erucic acid is a single unsaturated fatty acid that falls under the omega-9 fatty acid family. It was suggested to treat Wistar rats with lipopolysaccharide (LPS)-induced memory impairment and minimize cognitive impairment. A total of 30 animals were randomized: group I was normally treated group, group II was administered with LPS, group III was treated with LPS along with erucic acid at the dose of 10 mg kg–1 p.o.–1, group IV was treated with LPS along with erucic acid at 20 mg kg–1 p.o.–1 and group V was the erucic acid per se group provided at the dose of 20 mg kg–1 p.o.–1 per se. Behavioral tests were evaluated by using the Morris water maze and Y-maze. Biochemical analysis including acetylcholine esterase (AChE), choline acetyltransferase (ChAT), glutathione (GSH), catalase activity (CAT), superoxide dismutase (SOD), and nitric oxide (NO) along with proinflammatory mediators tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), caspase 3, and neuroinflammatory biomarker (nuclear factor kappa B-NF-κB) were measured. Erucic acid produced substantial behavioral improvement in the Y-maze test, including spontaneous alterations and reduced latency time during acquisition, and a longer duration of time in the consolidation phase undergoing the MWM test. Furthermore, erucic acid improved the AChE, proinflammatory markers, and oxidative stress as well as restoring endogenous antioxidant levels, ChAT, caspase 3, and NF-κB levels. Erucic acid may be a therapeutic component for conditions related to memory disorders such as memory impairment, enhances memory functioning, and protects against neuronal damage. 相似文献
554.
Asad Ullah Muhammad Samee Haider Malik Wajid Hussain Chan Sadar Aslam Lakht -e-Zehra Omer Mukhtar Tarar Nida Saleem Victoria Arija 《Journal of the American Oil Chemists' Society》2023,100(11):857-868
In this study, the effects of temperature on the fatty acids profile and the effects of temperature on the degree of unsaturation of fatty acids of Oreochromis niloticus were investigated. The analysis was performed by gas chromatography. The study showed that there were large temperature variations (10.0–32.0°C) during the study period (January–December). The highest crude fat content was found in January (3380 mg/100 g) and the lowest in June (2050 mg/100 g). The fatty acids profile showed significantly different diversity (p < 0.05). Total saturated fatty acid (∑SFA) content ranged from 409.54 to 1297.61 mg/100 g, monounsaturated fatty acid (∑MUFA) from 207.68 to 665.81 mg/100 g, and polyunsaturated fatty acid (∑PUFA) from 175.12 to 972.23 mg/100 g. The ∑MUFA and ∑PUFA concentrations were highest in January and lowest in June, and the ∑SFA concentration was lowest in January and highest in June. EPA and DHA contents were highest in January (198.96 mg/100 g) and lowest in June (48.76 mg/100 g). The contents of omega-3 (653.17 mg/100 g) and omega-6 fatty acids (252.54 mg/100 g) were highest in January and lowest in June (ω-3; 106.43 and ω-6; 60.91 mg/100 g). It concluded that the degree of unsaturation of fatty acids increases with decreasing temperature. In this study, the nutritional quality of the FAs profile was assessed using lipid quality indices. The indices indicating dietary quality of lipids by their values: Atherogenic index (0.47), thrombogenic index (0.38), hypocholesterolemic to hypercholesterolemic (3.00), meat fat quality (6.78), ω6/ω3 ratio (0.39), PUFA/SFA (2.37), MUFA/SFA (1.62), PUFA/MUFA (1.46), and PUFA + MUFA/SFA (3.99). These values are within the recommended range, indicating that the lipid profile of O. niloticus has high nutritional quality, which can be further improved by harvesting the fish during the winter season. Due to the nutritional importance of O. niloticus, the culture of this species could have significant interest to the people of Karachi, especially the coastal communities. To promote the nutritional diet in local population, the government should support the aquaculture of Nile tilapia. 相似文献