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81.
Saima Usman Hebah Aldehlawi Thuan Khanh Ngoc Nguyen Muy-Teck Teh Ahmad Waseem 《International journal of molecular sciences》2022,23(11)
Vimentin, a type III intermediate filament protein, is found in most cells along with microfilaments and microtubules. It has been shown that the head domain folds back to associate with the rod domain and this association is essential for filament assembly. The N-terminally tagged vimentin has been widely used to label the cytoskeleton in live cell imaging. Although there is previous evidence that EGFP tagged vimentin fails to form filaments but is able to integrate into a pre-existing network, no study has systematically investigated or established a molecular basis for this observation. To determine whether a tag would affect de novo filament assembly, we used vimentin fused at the N-terminus with two different sized tags, AcGFP (239 residues, 27 kDa) and 3 × FLAG (22 residues; 2.4 kDa) to assemble into filaments in two vimentin-deficient epithelial cells, MCF-7 and A431. We showed that regardless of tag size, N-terminally tagged vimentin aggregated into globules with a significant proportion co-aligning with β-catenin at cell–cell junctions. However, the tagged vimentin aggregates could form filaments upon adding untagged vimentin at a ratio of 1:1 or when introduced into cells containing pre-existing filaments. The resultant filament network containing a mixture of tagged and untagged vimentin was less stable compared to that formed by only untagged vimentin. The data suggest that placing a tag at the N-terminus may create steric hinderance in case of a large tag (AcGFP) or electrostatic repulsion in case of highly charged tag (3 × FLAG) perhaps inducing a conformational change, which deleteriously affects the association between head and rod domains. Taken together our results shows that a free N-terminus is essential for filament assembly as N-terminally tagged vimentin is not only incapable of forming filaments, but it also destabilises when integrated into a pre-existing network. 相似文献
82.
Sheeraz Akram Muhammad Younus Javed Ayyaz Hussain Farhan Riaz M. Usman Akram 《人工智能实验与理论杂志》2013,25(6):737-751
A computer-aided diagnostic (CAD) system for effective and accurate pulmonary nodule detection is required to detect the nodules at early stage. This paper proposed a novel technique to detect and classify pulmonary nodules based on statistical features for intensity values using support vector machine (SVM). The significance of the proposed technique is, it uses the nodules features in 2D & 3D and also SVM for the classification that is good to classify the nodules extracted from the image. The lung volume is extracted from Lung CT using thresholding, background removal, hole-filling and contour correction of lung lobe. The candidate nodules are extracted and pruned using the rules based on ground truth of nodules. The statistical features for intensity values are extracted from candidate nodules. The nodule data are up-samples to reduce the biasness. The classifier SVM is trained using data samples. The efficiency of proposed CAD system is tested and evaluated using Lung Image Consortium Database (LIDC) that is standard data-set used in CAD Systems for Lungs Nodule classification. The results obtained from proposed CAD system are good as compare to previous CAD systems. The sensitivity of 96.31% is achieved in the proposed CAD system. 相似文献
83.
Usman Shahzad Ishfaq Ahmad Ibrahim Mufrah Almanjahie Nadia H.Al –Noor 《计算机、材料和连续体(英文)》2021,68(3):3411-3430
Variance is one of the most vital measures of dispersion widely employed in practical aspects. A commonly used approach for variance estimation is the traditional method of moments that is strongly influenced by the presence of extreme values, and thus its results cannot be relied on. Finding momentum from Koyuncu’s recent work, the present paper focuses first on proposing two classes of variance estimators based on linear moments (L-moments), and then employing them with auxiliary data under double stratified sampling to introduce a new class of calibration variance estimators using important properties of L-moments (L-location, L-cv, L-variance). Three populations are taken into account to assess the efficiency of the new estimators. The first and second populations are concerned with artificial data, and the third populations is concerned with real data. The percentage relative efficiency of the proposed estimators over existing ones is evaluated. In the presence of extreme values, our findings depict the superiority and high efficiency of the proposed classes over traditional classes. Hence, when auxiliary data is available along with extreme values, the proposed classes of estimators may be implemented in an extensive variety of sampling surveys. 相似文献
84.
Dr. Sabina Yasmin Dr. Carmen Cerchia Dr. Vishnu Nayak Badavath Dr. Antonio Laghezza Prof. Fabrizio Dal Piaz Dr. Susanta K. Mondal Dr. Özlem Atlı Dr. Merve Baysal Dr. Sankaran Vadivelan Dr. S. Shankar Dr. Mohd Usman Mohd Siddique Dr. Ashok Kumar Pattnaik Dr. Ravi Pratap Singh Prof. Fulvio Loiodice Dr. Venkatesan Jayaprakash Prof. Antonio Lavecchia 《ChemMedChem》2021,16(3):484-498
Insulin resistance is a major pathophysiological feature in the development of type 2 diabetes (T2DM). Ferulic acid is known for attenuating the insulin resistance and reducing the blood glucose in T2DM rats. In this work, we designed and synthesized a library of new ferulic acid amides (FAA), which could be considered as ring opening derivatives of the antidiabetic PPARγ agonists Thiazolidinediones (TZDs). However, since these compounds displayed weak PPAR transactivation capacity, we employed a proteomics approach to unravel their molecular target(s) and identified the peroxiredoxin 1 (PRDX1) as a direct binding target of FAAs. Interestingly, PRDX1, a protein with antioxidant and chaperone activity, has been implied in the development of T2DM by inducing hepatic insulin resistance. SPR, mass spectrometry-based studies, docking experiments and in vitro inhibition assay confirmed that compounds VIe and VIf bound PRDX1 and induced a dose-dependent inhibition. Furthermore, VIe and VIf significantly improved hyperglycemia and hyperlipidemia in streptozotocin-nicotinamide (STZ-NA)-induced diabetic rats as confirmed by histopathological examinations. These results provide guidance for developing the current FAAs as new potential antidiabetic agents. 相似文献
85.
Muhammad Usman Tamour Zubair Muhammad Hamid Rizwan Ul Haq Zafar Hayat Khan 《亚洲传热研究》2021,50(4):3079-3093
The objective of the current article is to explore the unsteady flow and heat transfer of magnetohydrodynamics tangent-hyperbolic fluid flow over a stretching sheet. The governing flow model is transformed into a nonlinear set of ordinary differential equations by utilizing the appropriate similarity techniques. A new modification is introduced into the traditional Legendre wavelet method to obtain the results of the model mentioned above. The classic wavelet scheme is unable to find the solution for an infinite domain. Hence, we successfully extended it for an infinite domain and used it to attain the significant findings of the fluid problem. Additionally, the study of emerging parameters on temperature and velocity profiles is reported graphically. The velocity behavior is decreasing for the physical parameters, namely, power-lax index, unsteadiness, Hartmann number, and Weissenberg number. The temperature profile is an increasing function for power-law index and Eckert number while the behavior is the opposite for the Prandtl number. Moreover, a tabular form comparison of outcomes with existing literature, convergence, and error analysis is provided in our study, which confirms the credibility of the suggested method. The obtained results endorse the credibility and reliability of the proposed method; therefore, it could be extended for other nonlinear problems of complex nature. 相似文献
86.
Hafiz Muhammad Asif Javed Akbar Ali Qureshi Remsha Mehmood Muhammad Imran Tahir Sofia Javed Muhammad Sarfaraz M. Yasar Javaid Muhammad Awais Usman Ali 《International Journal of Hydrogen Energy》2021,46(27):14311-14321
Hydrogen treatment is a facile and efficient approach for the enhancement in the functioning of TiO2 nanoparticles for dye-sensitized solar cells (DSSC). In this work, TiO2 nanoparticles have been synthesized in the hydrogen environment followed by the deposition onto FTO glass substrates with various film thickness as photoanodes for DSSC. The synthesized hydrogen treated TiO2 nanoparticles based photoanodes have showed significantly improved photocurrent in the resulting fabricated devices. SEM and TEM analyses have confirmed the particle size and morphology of TiO2 nanoparticles at various magnifications. The crystalline structure and phase identification were studied by XRD analysis and Raman spectroscopic measurements. The UV–Vis spectroscopy analysis was carried out to find the response of samples for ultraviolet and visible light. The current-voltage measurements have confirmed the improvement of photocurrent that is principally due to improved photo-activity of hydrogen treated TiO2 nanoparticles. Moreover, hydrogen treated TiO2 nanoparticles-based photoanode with the film thickness of 11.65 μm has remarkably enhanced power conversion efficiency of 6.05% in DSSCs. The ability of highly photoactive hydrogen treated TiO2 nanoparticles will provide the new openings in different fields that include photo-electrochemical water splitting and in many other applications. 相似文献
87.
88.
Nadia Akram Khalid Mahmood Zia Muhammad Saeed Muhammad Usman Waheed Gul Khan 《应用聚合物科学杂志》2019,136(9):47124
The present work describes the role of accurate selection of diisocyanate on the adhesion strength of polyurethanes (PUs). The concentration of diisocyanate induces the hard segment (HS) in the main architecture of PUs which decides the viscoelastic properties of the polymers. A balanced ratio of viscoelastic properties ultimately determines the adhesion strength. The composition of the polymers consists of a blend of macrodiol of hydroxyl-terminated polybutadiene and polypropylene glycol with different molecular weights. Isophorone diisocyanate (IPDI) is used to develop the urethane linkages by maintaining its contribution from 28 to 67% as HS contents. It determines the adhesion strength of the final product. The adhesion strength is evaluated by texture analyzer and 180° peel test. The probe tack analysis shows maximum adhesion energy of 156.2 J cm−2 and 180° peel test shows 18.80 N/25 mm peel force. The glass-transition (T g) values obtained through differential scanning calorimetry are in good agreement with theoretically calculated Flory–Fox temperature. The proportion of the loss tangent to the storage modulus (tan δ/E′) shows the optimum value of 2.80 MPa−1. The ideal concentration of IPDI results to achieve better adhesion properties of PU pressure sensitive adhesives. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47124. 相似文献
89.
90.
Nadia Akram Khalid Mahmood Zia Muhammad Saeed Muhammad Usman Shahzad Zafar Iqbal Amina Shafi Waheed Gul Khan 《应用聚合物科学杂志》2020,137(13):48493
The diverse and ubiquitous consumption of polymers urges the necessity to make these materials easily available. However, the excessively used petrochemical-based polymers such as poly(vinyl) chloride (PVC) are nonbiodegradable, which is a motivation to modify it with “green” alternatives. In the present study, PVC (Mw = 48 000 g mol−1) has been incorporated with cornstarch (CS) to synthesize a series of 25 samples of bioplastics in addition to blank polymer samples. The films of five various thicknesses (0.1, 0.2, 0.3, 0.5, and 1.0 mm) have been synthesized using in situ polymerization. Each sample of pure PVC film and bioplastic has been induced with different concentrations of CS in the range of 1–5 wt %. The synthesized samples were subjected to the structural characterization by using Fourier transform infrared. Thermogravimetric analysis has demonstrated the three-step degradation with the improved stability of 250 °C. The 3% concentration of CS has shown the optimum storage modulus (E′) of 1 660 MPa from dynamic mechanical analysis and Tan δ as 0.50. The swelling test performed using water has shown an induction of hydrophilicity in PVC up to 4%. CS-induced bioplastics can be a potential ecofriendly alternative of conventional polymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48493. 相似文献