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991.
Linear isotherm regularity is applied to generate an expression for the direct correlation function (DCF), based on the optimized random-phase approximation theory. We use the Lennard-Jones potential in the modelling of real fluids, in which its molecular parameters are state-dependent. Based on the perturbation theory, we assume that the core contribution of the DCF is related to the geometric effect via a linear form, which arises from the excluded volume, and the tail contribution is related to the long-range intermolecular interactions of the system via a non-linear form. We use this model to predict the behaviour of the structure factor, S(k), in a wide range of k values for the xenon and krypton liquids. Finally, we compare our results with the experimental and theoretical data available in literature. The model is also successful in the presentation of the Ornstein–Zernike behaviour of S(k) at the low-k region. 相似文献
992.
Software products in the market are changing due to changes in business processes, technology, or new requirements from the customers. Maintainability of legacy systems has always been an inspiring task for the software companies. In order to determine whether the software requires maintainability by reverse engineering or by forward engineering approach, a system assessment was done from diverse perspectives: quality, business value, type of errors, etc. In this research, the changes required in the existing software components of the legacy system were identified using a supervised learning approach. New interfaces for the software components were redesigned according to the new requirements and/or type of errors. Software maintainability was measured by applying a machine learning technique, i.e., Naïve Bayes classifier. The dataset was designed based on the observations such as component state, successful or error type in the component, line of code of error that exists in the component, component business value, and changes required for the component or not. The results generated by the Waikato Environment for Knowledge Analysis (WEKA) software confirm the effectiveness of the introduced methodology with an accuracy of 97.18%. 相似文献
993.
Ahmed Arham S. Iqbal Arshad Shafi Adil Qais Faizan Abul Ahamad Tanveer Srivastava Seema 《Journal of Cluster Science》2021,32(6):1723-1737
Journal of Cluster Science - Currently eco-friendly green method is used for the synthesis of biocompatible pure and Ti doped cerium oxide nanoparticles. Various chemical methods have been reported... 相似文献
994.
Zafar Iqbal Jian Sun Haikang Yang Jingwen Ji Lili He Lijuan Zhai Jinbo Ji Pengjuan Zhou Dong Tang Yangxiu Mu Lin Wang Zhixiang Yang 《Molecules (Basel, Switzerland)》2022,27(12)
Antibacterial resistance towards the β-lactam (BL) drugs is now ubiquitous, and there is a major global health concern associated with the emergence of new β-lactamases (BLAs) as the primary cause of resistance. In addition to the development of new antibacterial drugs, β-lactamase inhibition is an alternative modality that can be implemented to tackle this resistance channel. This strategy has successfully revitalized the efficacy of a number of otherwise obsolete BLs since the discovery of the first β-lactamase inhibitor (BLI), clavulanic acid. Over the years, β-lactamase inhibition research has grown, leading to the introduction of new synthetic inhibitors, and a few are currently in clinical trials. Of note, the 1, 6-diazabicyclo [3,2,1]octan-7-one (DBO) scaffold gained the attention of researchers around the world, which finally culminated in the approval of two BLIs, avibactam and relebactam, which can successfully inhibit Ambler class A, C, and D β-lactamases. Boronic acids have shown promise in coping with Ambler class B β-lactamases in recent research, in addition to classes A, C, and D with the clinical use of vaborbactam. This review focuses on the further developments in the synthetic strategies using DBO as well as boronic acid derivatives. In addition, various other potential serine- and metallo- β-lactamases inhibitors that have been developed in last few years are discussed briefly as well. Furthermore, binding interactions of the representative inhibitors have been discussed based on the crystal structure data of inhibitor-enzyme complex, published in the literature. 相似文献
995.
Arshad Iqbal Ayaz Ali Sher Naveed Muhammad Syed Lal Badshah Abdul-Hamid Emwas Mariusz Jaremko 《Molecules (Basel, Switzerland)》2022,27(13)
Chrozophora tinctoria is an annual plant of the family Euphorbiaceae, traditionally used as a laxative, a cathartic and an emetic. A methanolic extract of Chrozophora tinctoria (MEC) whole plant and an n-butanol fraction of Chrozophora tinctoria (NBFC) were analyzed by gas chromatography–mass spectrometry (GC-MS) to detect the phytochemicals. MEC and NBFC were tested for in vitro anti acetylcholinesterase (AChE) potential. The effect of both samples on intestinal propulsive movement and spasmolytic activity in the gastrointestinal tract (GIT) was also studied. About twelve compounds in MEC and three compounds in NBFC were tentatively identified through GC-MS. Some of them are compounds with known therapeutic activity, such as toluene; imipramine; undecane; 14-methyl-pentadecanoic acid methyl ester; and hexadecanoic acid. Both NBFC and MEC samples were checked for acute toxicity and were found to be highly toxic in a dose-dependent manner, causing diarrhea and emesis at 1 g/kg concentration in pigeons, with the highest lethargy and mortality above 3 g/kg. Both the samples of Chrozophora tinctoria revealed significant (p ≤ 0.01) laxative activity against metronidazole (7 mg/kg) and loperamide hydrochloride (4 mg/kg)-induced constipation. NBFC (81.18 ± 2.5%) and MEC (68.28 ± 2.4%) significantly increased charcoal meal intestinal transit compared to distal water (41.15 ± 4.3%). NBFC exhibited a significant relaxant effect (EC50 = 3.40 ± 0.20 mg/mL) in spontaneous rabbit jejunum as compared to MEC (EC50 = 4.34 ± 0.68 mg/kg). Similarly, the impact of NBFC on KCl-induced contraction was more significant than that of MEC (EC50 values of 7.22 ± 0.06 mg/mL and 7.47 ± 0.57 mg/mL, respectively). The present study scientifically validates the folk use of Chrozophora tinctoria in the management of gastrointestinal diseases such as constipation. Further work is needed to isolate the phytochemicals that act as diarrheal agents in Chrozophora tinctoria. 相似文献
996.
Shazia Ishfaq Shazia Nisar Sadaf Iqbal Saqib Ali Syed Tariq Ali ElSayed Din Norah Salem Alsaiari Kholood A. Dahlous Muhammad Sufyan Javed Patrizia Bocchetta 《Molecules (Basel, Switzerland)》2022,27(23)
This article reports the synthesis, characterization, geometrical optimization, and biological studies of new MBH-based organometallic compounds of medicinal significance. The ligand (MNHA) was prepared via the Morita–Baylis–Hillman (MBH) synthetic route, from aromatic aldehyde containing multiple functional groups. Metal complexes were prepared in an alkaline medium and under other suitable reaction conditions. Spectral and elemental analyses were used to identify the structural and molecular formulas of each compound. Optimized geometry was determined through density functional theory (DFT) B3LYP and 6-311++ G (d,p) basis set for the MBH adduct, whereas structures of novel complexes were optimized with the semi-empirical PM6 method. Powder XRD analysis furnished the crystal class of complexes, with Co3+, Cr3+, and Mn2+ being cubic, while Ni2+ was hexagonal, and Cu2+ was orthorhombic. Moreover, the ligand, along with Ni2+ and Co3+ complexes, showed profound antibacterial action against S. aureus, E. coli, B. pumilis, and S. typhi. Additionally, all of the complexes were shown to persist in the positive antioxidant potential of the ligand. Contrarily, not a single metal complex conserved the antifungal potentials of the ligand. 相似文献
997.
Nano-Size Characterization and Antifungal Evaluation of Essential Oil Molecules-Loaded Nanoliposomes
Katya M. Aguilar-Prez Dora I. Medina Roberto Parra-Saldívar Hafiz M. N. Iqbal 《Molecules (Basel, Switzerland)》2022,27(17)
Nanoliposomes, bilayer vesicles at the nanoscale, are becoming popular because of their safety, patient compliance, high entrapment efficiency, and prompt action. Several notable biological activities of natural essential oils (EOs), including fungal inhibition, are of supreme interest. As developed, multi-compositional nanoliposomes loaded with various concentrations of clove essential oil (CEO) and tea tree oil (TTO) were thoroughly characterized to gain insight into their nano-size distribution. The present work also aimed to reconnoiter the sustainable synthesis conditions to estimate the efficacy of EOs in bulk and EO-loaded nanoliposomes with multi-functional entities. Following a detailed nano-size characterization of in-house fabricated EO-loaded nanoliposomes, the antifungal efficacy was tested by executing the mycelial growth inhibition (MGI) test using Trichophyton rubrum fungi as a test model. The dynamic light scattering (DLS) profile of as-fabricated EO-loaded nanoliposomes revealed the mean size, polydispersity index (PdI), and zeta potential values as 37.12 ± 1.23 nm, 0.377 ± 0.007, and −36.94 ± 0.36 mV, respectively. The sphere-shaped morphology of CEO and TTO-loaded nanoliposomes was confirmed by a scanning electron microscope (SEM). The existence of characteristic functional bands in all tested counterparts was demonstrated by attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. Compared to TTO-loaded nanoliposomes, the CEO-loaded nanoliposomes exhibited a maximum entrapment efficacy of 91.57 ± 2.5%. The CEO-loaded nanoliposome fraction, prepared using 1.5 µL/mL concentration, showed the highest MGI of 98.4 ± 0.87% tested against T. rubrum strains compared to the rest of the formulations. 相似文献
998.
Asma Bourafai-Aziez Daniel Jacob Gwladys Charpentier Emmanuel Cassin Guillaume Rousselot Annick Moing Catherine Deborde 《Molecules (Basel, Switzerland)》2022,27(17)
Acerola (Malpighia emarginata D.C.) is an exotic fruit with high agro-industrial potential due to its high content of ascorbic acid (AA), phenolic compounds, and carotenoid pigments. Acerola fruit is processed into concentrated juice or powder to be incorporated into food supplements. The ascorbic acid content of concentrated juice or powders must be controlled and well assessed. Therefore, the development of optimal methods and procedures for the rapid and accurate determination of the ascorbic acid content in juice concentrate and juice powder remains of considerable commercial interest. NMR spectroscopy is currently a powerful spectroscopic tool for the qualitative and quantitative analysis of molecules of all types and sizes. Firstly, this article presents the NMR-based metabolomic profiling of acerola juice and concentrate powder to describe and compare their composition. Thirty-six metabolites were identified. The AA over choline ratio and the NMR metabolomic profiles could be used for authentication in the future. Secondly, a rapid (8 min), reliable, and non-destructive method for the quantification of ascorbic acid by 1D 1H-NMR spectroscopy was developed and validated. The LOD and LOQ were 0.05 and 0.15 mg/mL, respectively. These two approaches could be combined to better characterize ingredients derived from acerola and incorporated into food supplements. 相似文献
999.
1000.
Muhammad Iqbal Michael McCullough Adam Harris S. Holger Eichhorn 《Journal of Thermal Analysis and Calorimetry》2012,108(3):933-938
Polyurethane composites containing spherical and flake-shaped silver fillers of micrometer and nanometer sizes were prepared by reacting suspensions of the silver filler in tetraethylene glycol with Desmodur? HL BA. Both the thermal conductivity and the stability of the silver composites are increased in comparison with a reference polyurethane sample without filler. Unexpectedly, the largest increases in thermal conductivity and stability are observed for the spherical silver particles of micrometer size but not for the silver nanoparticles, which is reasoned with larger aggregates of silver particles and a higher degree of crystallinity in the sample containing micrometer-sized silver particles. 相似文献