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236 results on '"Akhtar, Naureen"'

10. Artificial Neural Network (ANN) Trained by a Novel Arithmetic Optimization Algorithm (AOA) for Short Term Forecasting of Wind Power

Author

Zafar, Muhammad Hamza, Khan, Noman Mujeeb, Moosavi, Syed Kumayl Raza, Mansoor, Majad, Mirza, Adeel Feroz, Akhtar, Naureen, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Sanfilippo, Filippo, editor, Granmo, Ole-Christoffer, editor, Yayilgan, Sule Yildirim, editor, and Bajwa, Imran Sarwar, editor

Published
2022
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27. Nitrate transport and assimilation in Aspergillus nidulans

Author

Akhtar, Naureen, Kinghorn, Jim., and Unkles, Shiela

Subjects
579.5, Nitrate transporters, Aspergillus
Abstract

In this study, several aspects of nitrate assimilation and transport have been studied using the filamentous fungus Aspergillus nidulans, which has been shown to be safe laboratory organism as judged by it's pathogenicity towards insect larvae. In silico analysis of the A. nidulans genome sequence, identified two putative genes designated cnxL and cnxK that might be involved in molybdenum cofactor (a component of nitrate reductase) biosynthesis as well as two putative nitrate reductases encoding genes niaB and niaC. All four genes are hitherto unknown. Although many features of these proteins provided clues of functionality, biochemical and genetical approaches employed in this present study failed to elicit expression of any of these four genes. A NrtA protein structure model was developed based on residue homology with the E. coli GlpT a protein, the structure of which has been solved. The results of thiol cross-linking of three double cysteine mutants in four NrtA essential residues, R87, R368, N168 and N459, indicated that the molecular distance between R87 and R368 is ~ 0.4 Å, R368 and N168 ~ 6.2 Å, R87 and N459 is ~ 2.2 Å. Another important observation was the change in the confirmation of Tm 2 and Tm 8 in the presence of nitrate. This shift resulted in an increase of ~ 2 Å gap between the residues R87 and R368. Distances between amino acid residue pairs estimated using such molecular rulers contradicted the NrtA existing model. Cysteine-scanning mutagenesis studies were extended to the generation of a library of single cysteine mutants of NrtA residues spanning Tm 2 and Tm 8. The majority of single cysteine mutants possessed wild type NrtA protein expression levels but unfortunately most were found to be loss-of-function. Consequently, thiol chemistry of this crop of mutants was not perused. Attempts were also made to overexpress and crystallise the bacterial nitrate transporters but none of the transporter tested proved to be a successful candidate for crystallisation. In this regard, bacterial nitrate transporters, NarU (E. coli), Nar (Bacillus cereus), NarK1 and NarK2 (Pseudomonas aeruginosa) and NarK2 (Thermus thermophilus) fused with GFP were expressed in E. coli and used in crystallisation trials. Although this approach has proved successful for a number of membrane proteins, unfortunately was not helpful with regard to the purification of any of the above bacterial nitrate transporters to yield protein expression levels required for successful protein crystallography. Finally, the effects of potential nitrate transport inhibitors were studied on net nitrate transport by NrtA and NrtB proteins of A. nidulans. The results indicated that chlorate had more of an inhibitory effect on NrtA net nitrate transport than that by NrtB. Chlorite and sulphite equally affected net nitrate transport by either NrtA or NrtB proteins while caesium strongly inhibited the net nitrate transport by NrtB transporter.

Published
2012

38. A Novel MPPT Controller Based on Mud Ring Optimization Algorithm for Centralized Thermoelectric Generator under Dynamic Thermal Gradients.

Author

Zafar, Muhammad Hamza, Abou Houran, Mohamad, Mansoor, Majad, Khan, Noman Mujeeb, Moosavi, Syed Kumayl Raza, Khan, Muhammad Kamran, and Akhtar, Naureen

Subjects
OPTIMIZATION algorithms, THERMOELECTRIC generators, MUD, MAXIMUM power point trackers, INDUSTRIAL efficiency, HEAT recovery, RENEWABLE energy sources
Abstract

Most industrial processes generate raw heat. To enhance the efficiency of industrial operations, this raw heat is recovered. Thermoelectric generators (TEG), as solid state devices, provide an excellent application of heat recovery in the form of most manageable electrical power. This work presents a novel MPPT controller based on the Mud Ring Optimization algorithm for a centralized Thermoelectric Generator (TEG) under dynamic thermal gradients. The existing stochastic optimization algorithm for Maximum Power Point Tracking (MPPT) control in renewable energy systems exhibits several limitations that affect its performance in MPPT control. The convergence speed, local minima trap, hyper parameters' sensitivity toward the population size, acceleration coefficients, and the stopping criterion all impact the convergence stability. In addition to these limitations, sensor noise sensitivity in measurement fluctuates the control system leading to reduced performance. Therefore, the careful design and implementation of the MRO algorithm is crucial to overcome these limitations and achieve a satisfactory performance in MPPT control. The results of this study contribute to developing more efficient MPPT control of TEG systems and implementing renewable energy technologies. The algorithm effectively tracks the maximum power point in dynamic thermal environments and increases the power output compared to conventional MPPT methods. The findings illustrate the efficacy of the proposed controller providing a higher power output (Avg. 99.95%) and faster response time (220 ms) under dynamic thermal conditions achieving 38–70% faster tracking of the GM in dynamic operating conditions. [ABSTRACT FROM AUTHOR]

Published
2023
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41. Global Security And Human Rights.

Author

Safdar, Muhammad Asif, Akhtar, Naureen, Baig, Khurram, and Ahamad, Waqas

Subjects
HUMAN rights, WAR, INTERNATIONAL security, NATIONAL security, QUALITATIVE research
Abstract

This article describes the concept of global security with respect to human rights protection by using qualitative research methods. To this end, this article inspects the global perspective of war and how they are executed and their significance to highlight whether wars are the last resort. Further, this article critically investigates the law of war with reference to the human right perspective to analyze the restrictive and traditional approaches in using armed forces for settling wars and the state's responsibility in controlling the war. Then, this research paper focuses on state and global security with regard to human right protection to pinpoint how human rights law can help in controlling and discouraging the concept of wars for the promotion of global security. [ABSTRACT FROM AUTHOR]

Published
2022

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