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91.
Abdulrahman Aljannahi Roudha Abdulla Alblooshi Rashed Humaid Alremeithi Ioannis Karamitsos Noora Abdulkarim Ahli Asma Mohammed Askar Ikhlass Mohammed Albastaki Mohamed Mahmood Ahli Sanjay Modak 《Molecules (Basel, Switzerland)》2022,27(13)
Synthetic fibers are one of the most valuable trace lines of evidence that can be found in crime scenes. When textile fibers are analyzed properly, they can help in finding a linkage between suspect, victim, and the scene of the crime. Various analytical techniques are used in the examination of samples to determine relationships between different fabric fragments. In this exploratory study, multivariate statistical methods were investigated in combination with machine learning classification models as a method for classifying 138 synthetic textile fibers using Fourier transform infrared spectroscopy, FT-IR. The data were first subjected to preprocessing techniques including the Savitzky–Golay first derivative method and Standard Normal Variate (SNV) method to smooth the spectra and minimize the scattering effects. Principal Component Analysis (PCA) was built to observe unique patterns and to cluster the samples. The classification model in this study, Soft Independent Modeling by Class Analogy (SIMCA), showed correct classification and separation distances between the analyzed synthetic fiber types. At a significance level of 5%, 97.1% of test samples were correctly classified. 相似文献
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Gwaram NS Ali HM Abdulla MA Buckle MJ Sukumaran SD Chung LY Othman R Alhadi AA Yehye WA Hadi AH Hassandarvish P Khaledi H Abdelwahab SI 《Molecules (Basel, Switzerland)》2012,17(3):2408-2427
Alzheimer's disease (AD) is the most common form of dementia among older people and the pathogenesis of this disease is associated with oxidative stress. Acetylcholinesterase inhibitors with antioxidant activities are considered potential treatments for AD. Some novel ketone derivatives of gallic hydrazide-derived Schiff bases were synthesized and examined for their antioxidant activities and in vitro and in silico acetyl cholinesterase inhibition. The compounds were characterized using spectroscopy and X-ray crystallography. The ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays revealed that all the compounds have strong antioxidant activities. N-(1-(5-bromo-2-hydroxyphenyl)-ethylidene)-3,4,5-trihydroxybenzohydrazide (2) was the most potent inhibitor of human acetyl cholinesterase, giving an inhibition rate of 77% at 100 μM. Molecular docking simulation of the ligand-enzyme complex suggested that the ligand may be positioned in the enzyme's active-site gorge, interacting with residues in the peripheral anionic subsite (PAS) and acyl binding pocket (ABP). The current work warrants further preclinical studies to assess the potential for these novel compounds for the treatment of AD. 相似文献
95.
Alshawsh MA Abdulla MA Ismail S Amin ZA Qader SW Hadi HA Harmal NS 《Molecules (Basel, Switzerland)》2012,17(5):5385-5395
Orthosiphon stamineus is considered an important traditional folk medicine. In this study ethanol and aqueous extracts of O. stamineus were evaluated in vitro for their antioxidant, antimicrobial as well as for their immunomodulatory properties on human peripheral blood mononuclear cells (PBMCs). The DPPH radical scavenging method was used for the determination of antioxidant activity, while the antibacterial efficacy was investigated by both disc diffusion method and Minimum Inhibitory Concentration (MIC) against four bacterial strains (Gram-positive and Gram-negative). Furthermore, the immunomodulatory potential of the extracts was investigated through the MTT assay. Aqueous extract of O. stamineus exhibited significant free radical scavenging activity with IC?? 50 9.6 μg/mL, whereas the IC?? for the ethanol extract was 21.4 μg/mL. The best antimicrobial activity was shown by the aqueous extract of O. stamineus against Staphylococcus aureus, with inhibition zone of 10.5 mm and MIC value 1.56 mg/mL. Moreover, the results observed from the MTT assay showed that both plant extracts stimulated the PBMCs proliferation in vitro in a concentration-dependent manner, but the aqueous extract has remarkable activity against PBMCs. These findings indicate that O. stamineus showed high antioxidant activity and may be considered as an immunomodulatory agent. 相似文献
96.
Juahir Yusnita Subramaniam Puvaneswary Mahmood Ameen Abdulla Ward T. Robinson Hapipah Mohd Ali 《Journal of chemical crystallography》2009,39(9):615-618
Abstract 2,6-Diacetylpyridinebis(benzenesulfonylhydrazide) (2,6-DAPBSH) and its zinc(II) complex have been synthesized and characterized
by X-ray crystallography. The ligand crystallizes in the monoclinic crystal system, space group Cc, with cell parameter = 16.808(2) Ǻ, b = 16.328(2) Ǻ, c = 8.2670(11) Ǻ, β = 91.869(9)°, while the zinc(II) complex crystallizes in the orthorhombic crystal system, space group Pbcn, with cell parameters a = 14.5927(3) Ǻ, b = 9.6502(2) Ǻ, c = 20.5610(5) Ǻ. The metal center is seven-coordinate, with an approximate pentagonal bipyramidal configuration of the chelating
ligand and two apically coordinated DMSO molecules.
Graphical Abstract X-ray crystallographic study on the [2,6-diacetylpyridine—bis(benzenesulfonylhydrazonato-κ5
N′N′′N′′′O′O′′)]bis(dimethyl sulfoxide-κO)zinc(II) (Fig. 1) shows that the complex is a seven-coordinate, with an approximate pentagonal
bipyramidal configuration where the ligand coordinates to the zinc(II) ion as a pentadentate chelate via the pyridine nitrogen
atom, the two azomethine nitrogen atoms and the two sulfonyl oxygen atoms.
相似文献
97.
Smaoui Nejib; Zribi Mohamed; Almulla Abdulla 《IMA Journal of Mathematical Control and Information》2006,23(3):301-323
** Email: smaoui{at}mcs.sci.kuniv.edu.kw This paper deals with the sliding mode control (SMC) of theforced generalized Burgers equation via the Karhunen-Loève(K-L) Galerkin method. The decomposition procedure of the K-Lmethod is presented to illustrate the use of this method inanalysing the numerical simulations data which represent thesolutions of the forced generalized Burgers equation for viscosityranging from 1 to 100. The K-L Galerkin projection is used asa model reduction technique for non-linear systems to derivea system of ordinary differential equations (ODEs) that mimicsthe dynamics of the forced generalized Burgers equation. Thedata coefficients derived from the ODE system are then usedto approximate the solutions of the forced Burgers equation.Finally, static and dynamic SMC schemes with the objective ofenhancing the stability of the forced generalized Burgers equationare proposed. Simulations of the controlled system are givento illustrate the developed theory. 相似文献
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This paper establishes a necessary and sufficient condition for the existence of a unique bounded solution to the classical Dirichlet problem in arbitrary open subset of RN (N≥3) with a non-compact boundary. The criterion is the exact analogue of Wiener’s test for the boundary regularity of harmonic functions and characterizes the “thinness” of a complementary set at infinity. The Kelvin transformation counterpart of the result reveals that the classical Wiener criterion for the boundary point is a necessary and sufficient condition for the unique solvability of the Dirichlet problem in a bounded open set within the class of harmonic functions having a “fundamental solution” kind of singularity at the fixed boundary point. Another important outcome is that the classical Wiener’s test at the boundary point presents a necessary and sufficient condition for the “fundamental solution” kinds of singularities of the solution to the Dirichlet problem to be removable. 相似文献
100.
Sobhi M. Gomha Hassan M. Abdel-aziz Mohamed G. Badrey Mohamed M. Abdulla 《Journal of heterocyclic chemistry》2019,56(4):1275-1282
The current study in this article concerned with construction of five‐membered heterocycles with multiple heteroatoms as nitrogen and sulfur from readily available starting materials and reagents. Treatment of 1‐(2‐oxo‐2H‐chromene‐3‐carbonyl)‐3‐phenyl‐1H‐pyrazol‐5(4H)‐one with each of phenylisothiocyanate in alcoholic potassium hydroxide and carbon disulfide in basic medium gave rise to a thioanilide and methylthio derivatives, respectively. Treatment of the latter compounds with a variety of hydrazonoyl halides resulted in construction of thiadiazole moiety linked to pyrazole ring. Furthermore, triazole derivatives were synthesized from the thioanilide derivative through its reaction with methyl iodide followed by reaction with hydrazonoyl halides. 5α‐Reductase inhibition activity for the prepared compounds was investigated against the reference drug anastrozole, and the results showed that the inhibition activity of compounds 5g and 11g is more potent than anastrozole. Also compounds bearing triazole moiety is more potent than compounds bearing thiadiazole one. Moreover, the anti‐prostate cancer screening anti‐androgenic bioassay in human prostate cancer cells for the tested compounds was evaluated, and the results showed great inhibition growth and potential antiandrogens. 相似文献