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51.
Abdullah M Assiri Bakri I Yousuf J Margaret Woodhouse Andrew J Quantock Paul J Murphy 《Contact lens & anterior eye》2006,29(2):75-79
Here, we describe a case in which A-scan ultrasound biometry was used to differentially diagnose the cause of reduced vision in a patient with keratoconus. A patient with keratoconus presented with reduced visual acuity in one eye, not improvable above 6/18 with specialist keratoconus contact lens fitting. This monocular amblyopia was attributed to previous anisometropic ametropia by the use of ultrasound biometry. The report demonstrates the usefulness of ultrasound biometry in the detection of amblyopia in circumstances in which a previous assessment of amblyopia is not possible. This information will impact upon decisions made for the future clinical management in this case, especially if vision deteriorates so that a corneal graft is required. 相似文献
52.
Serap Kılıç Altun;Mehmet Emin Aydemir;Kasım Takım;Mustafa Abdullah Yilmaz; 《Food Science & Nutrition》2024,12(9):6298-6314
The objective of this study was to assess the impact of marinating beef, chicken, and fish with Micromeria fruticosa (M. fruticosa) on the inhibition of Nε-(carboxyethyl)lysine (CEL) and Nε-(carboxymethyl)lysine (CML). Furthermore, our objective was to examine how different cooking techniques, temperatures, and durations affect the creation of CEL and CML in these meat products. The study began with the characterization of M. fruticosa. Subsequently, meat samples were marinated using an M. fruticosa-containing marinade and stored at 4 ± 1°C for 24 h. Following storage, the meats underwent cooking in an oven at 200°C for 12 min and in an air fryer at 250°C for 8 min. Subsequently, pH, color, thiobarbituric acid reactive substances (TBARS), as well as CEL and CML analyses were conducted. M. fruticosa had high levels of biological activity and bioactive content. Moreover, increasing the M. fruticosa ratio in the marinade demonstrated a reduction in TBARS, CML, and CEL formation. This study concludes that M. fruticosa can be effectively used as a marinade component for meat, inhibiting the formation of CEL and CML. In conclusion, this research underscores the significant potential of M. fruticosa in reducing the synthesis of advanced glycation end products (AGEs) during meat processing. These results not only enhance our comprehension of the complex relationship between plant extracts and meat quality but also present encouraging prospects for fostering healthier and safer cooking methods. 相似文献
53.
Waqas Ahmad Khan;Muhammad Inam-ur-Raheem;Hina Rasheed;Muhammad Abdullah Butt;Farhan Saeed;Muhammad Afzaal;Faiyaz Ahmed;Noor Akram;Aasma Asghar;Gebremichael Gebremedhin Hailu; 《Food Science & Nutrition》2024,12(11):9673-9681
This study investigates the hepatoprotective effects of olive oil and flaxseed oil on chemically induced hepatotoxicity in rats by evaluating key biochemical parameters, including free fatty acids, iodine value, liver enzymes (ALP, ALT, AST), cholesterol, triglycerides, and HDL levels. The results demonstrated significant improvements in these markers with the administration of olive oil and flaxseed oil, either individually or in combination. The free fatty acid percentages and iodine values were consistent with the known nutritional properties of the oils. Notably, the combination of olive oil and flaxseed oil yielded the most substantial benefits, reducing ALP (115.53 ± 0.44 U/L), ALT (50.77 ± 1.46 U/L), and AST (52.12 ± 0.36 U/L) levels while improving lipid profiles by lowering cholesterol (135.4 ± 1.43 mg/dL) and triglyceride levels (57.14 ± 2.35 mg/dL) and increasing HDL levels (49.20 ± 0.45 mg/dL). These findings suggest that olive oil and flaxseed oil, due to their antioxidant and anti-inflammatory properties, can effectively mitigate liver damage and promote lipid metabolism. The study supports the potential therapeutic application of these oils in managing liver health and preventing hepatotoxicity. 相似文献
54.
M. Atikur Rahman;Zahid Hasan;Hasan Khaled Rouf;M. Khurshed Alam;A. K. M. Akther Hossain;M. N. I. Khan;M. R. Mohammad;Abdullah Alodhayb;Saikh Mohammad;Rajesh Haldhar;M. Khalid Hossain; 《International Journal of Applied Ceramic Technology》2024,21(5):3632-3644
This study investigates the magnetoelectric coupling effect in dual-phase multiferroic composites prepared using a solid-state reaction method. The composites were fabricated with the formula (1−x)Ba₀.₇₇Ca₀.₂₃TiO₃(BCT) + xNi₀.₆Zn₀.₂₅La₀.₁₅Fe₂O₄(NZLFO), where x varied from 0% to 100% in 10% increments. Ca-doped BaTiO₃ served as the ferroelectric phase, while La-doped Ni–Zn ferrite acted as the ferromagnetic phase. The effects of varying ferrite content (x) on structural, optical, ferroelectric, electrical, and magnetoelectric properties were comprehensively analyzed. X-ray diffraction (XRD) with Rietveld refinement revealed a spinel cubic structure for the ferrite phases and a tetragonal structure for the perovskite phases. The study observed a moderate influence of ferrite concentration on the lattice parameters of BCT and an opposing effect on the lattice parameters of NZLFO. Optical measurements indicated higher light absorption in the visible range compared to the UV region and wide optical bandgap. Magnetic properties, characterized by saturation magnetization, exhibited a dependence on temperature, with a Curie temperature (Tc) of 700 K. Electrical resistivity displayed a maximum at x = 50% and remained constant at high frequencies. The study also confirmed the presence of electric polarization induced by a magnetic field, with the highest magnetoelectric coefficient observed at x = 10%. These findings demonstrate the successful fabrication of dual-phase multiferroic composites with tunable properties through controlled ferrite content. The observed magnetoelectric coupling suggests potential applications in multifunctional devices. 相似文献
55.
This paper proposes a signal feedback interference topology to control the characteristics of a coupled line bandpass filter. Control is carried out by varying the ratio of the transmission line parameters of the forward and the feedback couplers. The topology produces a compact filter that does not require a complicated design or fabrication. The results of the insertion and return losses show that the feedback‐controlled design has desirable features in terms of the design frequency, fractional bandwidth, stopband rejection level, roll‐off rate and insertion loss. The test results of the fabricated prototype achieved good agreement with the simulation results of the ideal transmission line design model. Several microwave, modern wireless and mobile/satellite communication systems may benefit from such a filter design due to its compactness and flexibility. 相似文献
56.
Malak Albagami Abdullah Alrasheed Mervat Alharbi Abrar Alhazmi Kin Wong Hussam Qasem Sarah Alodan Olaiyan Alolaiyan Kang L. Wang Moh. R. Amer 《Advanced Electronic Materials》2020,6(5)
Layered hafnium diselenide (HfSe2) is an emerging Van der Waals semiconductor in which a hafnium layer is sandwiched between two selenium layers. Owning to its indirect band gap with magnitudes close to silicon's band gap and high predicted carrier mobility, hafnium diselenide material is a strong candidate for device applications. Here, the effect of laser treatment on 2H‐ HfSe2 devices is shown in ambient conditions using µ‐Raman spectroscopy. It is shown that an emerging Raman peak evolves with increasing laser exposure time. It is also shown that top‐down fabricated 2H‐HfSe2 devices exhibit an anomalous p‐type behavior post laser treatment, with Ion/Ioff ratio as high as 103. This anomalous conductivity change can be observed after thermal and electrical annealing. For bottom‐up devices, it is observed that p‐type conductivity with remarkable Ion/Ioff ratio reaching 104. This conductivity switch can also be shown on 1T‐HfSe2 devices post laser irradiation and high Vds bias treatments. Based on the circuit model, this conductivity switch is attributed to contact doping caused by an increase in the Schottky barrier height at each contact, which shifts the Fermi energy closer to the valance band. These results demonstrate a unique conductivity switching mechanism for HfSe2‐FET devices. 相似文献
57.
Tongwei Wu Haitao Zhao Xiaojuan Zhu Zhe Xing Qian Liu Tong Liu Shuyan Gao Siyu Lu Guang Chen Abdullah M. Asiri Yanning Zhang Xuping Sun 《Advanced materials (Deerfield Beach, Fla.)》2020,32(30):2000299
The ambient electrocatalytic N2 reduction reaction (NRR) enabled by TiO2 has attracted extensive recent attention. Previous studies suggest the formation of Ti3+ in TiO2 can significantly improve the NRR activity, but it still remains unclear what kinds of Ti3+ are effective. Herein, it is demonstrated that mixed-valent Cu acts as an effective dopant to modulate the oxygen vacancy (VO) concentration and Ti3+ formation, which markedly improves the electrocatalytic NRR performance. In 0.5 m LiClO4, this electrocatalyst attains a high Faradic efficiency of 21.99% and a large NH3 yield of 21.31 µg h−1 mgcat.−1 at –0.55 V vs reversible hydrogen electrode, which even surpasses most reported Ti-based NRR electrocatalysts. Using density function theory calculations, it is evidenced that mixed-valent Cu ions modulate the TiO2 (101) surface with multiple oxygen vacancies, which is beneficial for generating different Ti3+ 3d1 defect states localized below the Fermi energy. N2 activation and adsorption are effectively strengthened when Ti3+ 3d1 defect states present the splitting of eg and t2g orbitals, which can be modulated by its coordination structure. The synergistic roles of the three ion pairs formed by the VO defect, including Cu1+–Ti4+, Ti3+–Ti4+ and Ti3+–Ti3+, are together responsible for the enhanced NRR performance. 相似文献
58.
Shahram Golzari Mojtaba Shabani Haji Abdullah Khalili 《Computational Intelligence》2020,36(3):1140-1160
Predicting the delay in servicing incoming ships to ports is crucial for maritime transportation. In this study, we use support vector regression (SVR) in order to accurately predict this delay for ships arriving to the terminal No. 1 of Shahid Rajaee's port in Bandar Abbas. To achieve this goal, a combination of Clonal Selection and Grey Wolf Optimization algorithms (named as CLOGWO) is used for two purposes: (i) selecting the most important features among the features that affect prediction of this delay and (ii) optimizing SVR parameters for a more accurate prediction. Performance of the proposed method was compared with Genetic Algorithm (GA), Clonal Selection (CS), Grey Wolf Optimization (GWO), and Particle Swarm Optimization (PSO) algorithms on the following metrics: correlation, rate of feature reduction, root mean square error (RMSE), and normalized RMSE (NRMSE). Evaluations on Shahid Rajaee dataset showed that the mean value of these metrics in 10 independent runs of the proposed method were 0.867, 74.45%, 0.080, and 9.02, respectively. These results and evaluations on standard datasets indicate that the proposed method provides competitive results with other evolutionary algorithms. 相似文献
59.
Significant emergency measures should be taken until an emergency event occurs. It is understood that the emergency is characterized by limited time and information, harmfulness and uncertainty, and decision-makers are always critically bound by uncertainty and risk. This paper introduces many novel approaches to addressing the emergency situation of COVID-19 under spherical fuzzy environment. Fundamentally, the paper includes six main sections to achieve appropriate and accurate measures to address the situation of emergency decision-making. As the spherical fuzzy set (FS) is a generalized framework of fuzzy structure to handle more uncertainty and ambiguity in decision-making problems (DMPs). First, we discuss basic algebraic operational laws (AOLs) under spherical FS. In addition, elaborate on the deficiency of existing AOLs and present three cases to address the validity of the proposed novel AOLs under spherical fuzzy settings. Second, we present a list of Einstein aggregation operators (AgOp) based on the Einstein norm to aggregate uncertain information in DMPs. Thirdly, we are introducing two techniques to demonstrate the unknown weight of the criteria. Fourthly, we develop extended TOPSIS and Gray relational analysis approaches based on AgOp with unknown weight information of the criteria. In fifth, we design three algorithms to address the uncertainty and ambiguity information in emergency DMPs. Finally, the numerical case study of the novel carnivorous (COVID-19) situation is provided as an application for emergency decision-making based on the proposed three algorithms. Results explore the effectiveness of our proposed methodologies and provide accurate emergency measures to address the global uncertainty of COVID-19. 相似文献
60.
Arif M. Abdullah Xiuling Li Paul V. Braun John A. Rogers K. Jimmy Hsia 《Advanced functional materials》2020,30(14)
Self‐assembly of 3D structures presents an attractive and scalable route to realize reconfigurable and functionally capable mesoscale devices without human intervention. A common approach for achieving this is to utilize stimuli‐responsive folding of hinged structures, which requires the integration of different materials and/or geometric arrangements along the hinges. It is demonstrated that the inclusion of Kirigami cuts in planar, hingeless bilayer thin sheets can be used to produce complex 3D shapes in an on‐demand manner. Nonlinear finite element models are developed to elucidate the mechanics of shape morphing in bilayer thin sheets and verify the predictions through swelling experiments of planar, millimeter‐scaled PDMS (polydimethylsiloxane) bilayers in organic solvents. Building upon the mechanistic understandings, The transformation of Kirigami‐cut simple bilayers into 3D shapes such as letters from the Roman alphabet (to make “ADVANCED FUNCTIONAL MATERIALS”) and open/closed polyhedral architectures is experimentally demonstrated. A possible application of the bilayers as tether‐less optical metamaterials with dynamically tunable light transmission and reflection behaviors is also shown. As the proposed mechanistic design principles could be applied to a variety of materials, this research broadly contributes toward the development of smart, tetherless, and reconfigurable multifunctional systems. 相似文献