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101.
Taher M. Ghazal Sagheer Abbas Sundus Munir M. A. Khan Munir Ahmad Ghassan F. Issa Syeda Binish Zahra Muhammad Adnan Khan Mohammad Kamrul Hasan 《计算机、材料和连续体(英文)》2022,70(3):5005-5020
Alzheimer's disease is a severe neuron disease that damages brain cells which leads to permanent loss of memory also called dementia. Many people die due to this disease every year because this is not curable but early detection of this disease can help restrain the spread. Alzheimer's is most common in elderly people in the age bracket of 65 and above. An automated system is required for early detection of disease that can detect and classify the disease into multiple Alzheimer classes. Deep learning and machine learning techniques are used to solve many medical problems like this. The proposed system Alzheimer Disease detection utilizes transfer learning on Multi-class classification using brain Medical resonance imagining (MRI) working to classify the images in four stages, Mild demented (MD), Moderate demented (MOD), Non-demented (ND), Very mild demented (VMD). Simulation results have shown that the proposed system model gives 91.70% accuracy. It also observed that the proposed system gives more accurate results as compared to previous approaches. 相似文献
102.
Zahra S. Ahmed G. M. Abd El-Moniem A. A. E. Yassen 《Molecular nutrition & food research》1996,40(6):305-309
A defatted flour sample of sorghum and pearl millet were separated into three fractions. These procedures involve extracting the defatted flour with aqueous sodium hydroxide (pH 11.9) followed by precipitation with diluted HCl acid (pH 4.8). The two protein fractions I (soluble at pH 4.8) and II (insoluble at pH 4.8) along with the remaining residues (fraction III) were lyophilized separately. The amino acid composition of the original flour and the three fractions were determined. Lysine seems to be the most deficient amino acid in the original flour and the remaining residues. Fraction I and II, in which the lysine accumulated, have essentially better amino acid profile and consequently nutritionally better quality than the protein of the original defatted flour. The recovered protein-rich fractions I and II should be useful as a protein ingredient in foods. The remaining residues can be extruded into convenience foods. 相似文献
103.
Hossein Mirsaeedghazi Zahra Emam-Djomeh Sayed Mohammad Mousavi Abdolreza Aroujalian & Mahdi Navidbakhsh 《International Journal of Food Science & Technology》2009,44(11):2135-2141
The effect of pressure, velocity, pretreatment, membrane type and pore size on fouling mechanisms were evaluated. Pomegranate juice was treated with polyvinylidene fluoride (PVDF) 0.22 μm and mixed cellulose ester (MCE) 0.1 μm at different pressures. Cake formation which was the dominant mechanism was formed in the first stages of process and, as the filtration proceeded, intermediate, standard, and complete blocking, respectively occurred at higher pressure (5 kPa). At lower pressure (0.5 kPa) the last mechanism did not occur. Results showed that cake formation was the only mechanism in MCE 0.22 μm, however, others occurred with MCE 0.1 μm and PVDF 0.22 μm. Using MCE 0.22 μm prior to MCE 0.025 μm can reduce the role of cake formation in pore blocking. Evaluation of the impact of velocity showed that at the higher velocity (0.53 m s−1 ) the complete blocking occurred faster than at the lower velocity (0.09 m s−1 ). 相似文献
104.
Carbon-black–epoxy composite films were prepared by cathodic electro-deposition of a dispersion containing carbon black and epoxy resins. The films, after baking at elevated temperature, show a semi-conducting behavior. Using DC conductivity measurements it was possible to determine the glass transition temperature of the samples, the conductivities of which lie in the sensitivity range of the instrument. Conductive samples show a positive temperature coefficient both below and above Tg. Based on the electrical impedance data extracted from the electrochemical impedance spectra, the exponents x and y were determined for the frequency dependence of the complex conductivity and complex dielectric constant as 0.8 and 0.2, respectively. These values are in good agreement with the classical values of x = 0.72 and y = 0.28. It was also found that these exponents are the same for all the CCB contents studied. 相似文献
105.
Qualitative and quantitative evaluation of heart sound reduction from lung sound recordings 总被引:1,自引:0,他引:1
Gnitecki J Hossain I Pasterkamp H Moussavi Z 《IEEE transactions on bio-medical engineering》2005,52(10):1788-1792
Recursive least squares (RLS) adaptive noise cancellation (ANC) and wavelet transform (WT) ANC have been applied and compared for heart sound (HS) reduction from lung sounds (LS) recordings. Novel processes for quantitative and qualitative evaluation of any method for HS reduction from LS have also been proposed. 相似文献
106.
The creep-rupture behaviour of a Type DIN 1.4970 austenitic stainless steel has been investigated at 973 K (700°C) in a high vacuum for three conditions of thermomechanical treatment and a wide range of applied stresses using foil specimens of 105 μm thickness. After solution-annealing at 1373 K (1100°C) for all specimens, the three treatments were: — condition 1: 13% cold-worked — condition2: aged for 24 h at 1073 K (800°C) and 13% cold-worked — condition 3: (“Standard condition”): 13% cold-worked and aged for 24 h at 1073 K (800°C).The rupture lives and the minimum creep rates were found to be highly dependent on the applied stresses. The treatment of condition 1 material yielded a product as strong as the “standard” condition 3, while the condition 2 material was less creep resistant.Structural changes as well as fractography were followed using metallographic, transmission and scanning electron microscope techniques. Transgranular ductile fracture was clearly observed in all three conditions. TEM investigations showed that dispersive TiC precipitates were present in the matrix of condition 3 material before creep testing, contrary to condition 1 and 2 material. In condition 1, the TiC dispersion was already found after short creep times, while no dispersive TiC precipitates were found in condition 2 material in any test condition. 相似文献
107.
Masoud Hashempour Zahra Mashreghian Arani Fabrizio Lombardi 《Journal of Electronic Testing》2009,25(1):25-37
In self-assembly, individual components (commonly referred to as tiles) have sufficient infor mation to build templates for
structures such as lat tices for two-dimensional scaffolds. Tile sets that can heal (fully or partially) an erroneous DNA
assembly have been proposed. Healing requires growth to be restarted such that erroneous tiles can be removed and the correct
tiles can bind to the aggregate. Punctures have been proposed for this purpose; in this paper, a puncture is intentionally
induced in the self-assembly to restart the growth process. The goal of this paper is to characterize an intentionally induced
puncture (and its relevant properties) on an erroneous tile site in the grown crystal as part of a healing process. This allows
to propagate any newly generated error away from the source of growth (i.e. the seed tile), such that self-assembly can continue
along specific directions. Different types of puncture are considered with respect to healing and related features, such as
growth direction, error and aggregate types. Punctures are analyzed using a new characterization and metric; different tile
sets are investigated in detail for healing of a DNA self-assembly.
相似文献
Fabrizio LombardiEmail: |
108.
Amorphous silica gel modified carbon paste electrode (CPE) offers substantial improvements in voltammetric sensitivity and selectivity towards determination of dopamine (DA). Cyclic voltammetry of Fe(CN)63−/4− as a negatively charged probe revealed that the surface of the silica gel modified carbon paste electrode had a high density of negative charge at pH 8.0. Therefore, the modified electrode adsorbed DA (pKa = 8.9) and enhanced its voltammetric response while repulsed ascorbic acid (AA) (pKa = 4.2) and uric acid (UA) (pKa = 5.4) and inhibited their interfering effects. The influence of various experimental parameters including percent of silica gel in the CPE, pH of solution, and accumulation time and potentials, on the voltammetric response of DA was investigated. At the optimum conditions, the analytical curve was linear for dopamine concentrations from 2.0 × 10−7 to 1.0 × 10−6 mol L−1 and 2.0 × 10−6 to 1.5 × 10−4 mol L−1 with a detection limit (3σ) of 4.8 × 10−8 mol L−1. The prepared electrode was used for determination of DA spiked into DA injection and human serum samples, and very good recovery results were obtained over a wide concentration range of DA. 相似文献
109.
Yousef Kazemzadeh Behnam Dehdari Zahra Etemadan Masoud Riazi Mohammad Sharifi 《石油科学(英文版)》2019,(3):578-590
Nanofluids because of their surface characteristics improve the oil production from reservoirs by enabling different enhanced recovery mechanisms such as wettability alteration, interfacial tension (IFT) reduction, oil viscosity reduction, formation and stabilization of colloidal systems and the decrease in the asphaltene precipitation. To the best of the authors’ knowledge, the synthesis of a new nanocomposite has been studied in this paper for the first time. It consists of nanoparticles of both SiO2 and Fe3O4. Each nanoparticle has its individual surface property and has its distinct effect on the oil production of reservoirs. According to the previous studies, Fe3O4 has been used in the prevention or reduction of asphaltene precipitation and SiO2 has been considered for wettability alteration and/or reducing IFTs in enhanced oil recovery. According to the experimental results, the novel synthesized nanoparticles have increased the oil recovery by the synergistic effects of the formed particles markedly by activating the various mechanisms relative to the use of each of the nanoparticles in the micromodel individually. According to the results obtained for the use of this nanocomposite, understanding reservoir conditions plays an important role in the ultimate goal of enhancing oil recovery and the formation of stable emulsions plays an important role in oil recovery using this method. 相似文献
110.
Merikhi Behnaz Mirjalili Seyed Mohammad Zoghi Milad Mirjalili Seyedeh Zahra Mirjalili Seyedali 《Photonic Network Communications》2019,38(1):167-176
Photonic Network Communications - This paper proposes an effective method for shaping the radiation pattern intensity of photonic crystal (PhC) light-emitting diode (LED). In this method, the... 相似文献