Self-assembly of artificial peroxidase mimics from alternating copolymers with chromogenic and biocatalyst potentialities

Tahir Rasheed,Faran Nabeel,Muhammad Bilal 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.78 No.-

Inspiring from the multiple functions and delicate architectures of natural peroxidases, we constructedan artificial peroxidase that can mimic as horseradish peroxidase (HRP). This mimicking construct wasengineered by the self-assembly of alternating copolymers followed by encapsulation of hemin resultedin a functional vesicle exhibiting activity like peroxidase. The thiazole moiety present in copolymers poly(ethylene glycol)diglycidyl ether-alt-Bismuth-thiol P(PEGDGE-a-BTT) and 1,7-butadiene-diepoxide-alt-Bismuth-thiol P(BDD-a-BTT) can easily coordinate with hemin molecule. In this complex, hemin ispresent as a pentacoordinate ligand having an open site for substrate binding similar to themicroenvironment in natural peroxidase. The as-prepared functional vesicles exhibited better stabilityand excellent catalytic activity in oxidizing orange II (azo dye) and phenolic compounds such as catecholand 3, 30 , 5, 50-tetramethylbenzidine (TMB) using hydrogen peroxide (H2O2) as compared to HRP over awide pH, temperature range, and substrate concentrations. Another striking feature of these functionalvesicles (alternating polymer vesicles loaded with hemin) is their use as recognition systems forchromogenic substances, indicating that these vesicles can be used as new biocatalysts for specificfunctions.

Analysing the Causes of Design Generated Waste through System Dynamics

Sidra Muzaffar,Khurram Iqbal Ahmad Khan,Muhammad Bilal Tahir,Hamna Bukhari 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.12

A drastic rise in construction waste observed has elicited a radical impact on the environment and economy of the world. It is, therefore, necessary to come up with waste minimization management strategies that reflect in-depth review of sources of waste. This in depth review demands understanding the intricacy of causative factors triggering generation of “waste at source” which is the main motive of study and is done through System Dynamics for design phase in context of developing countries. 8 most important causative factors in design phase were shortlisted along with their interrelationships via literature and questionnaire survey. Followed by system thinking approach that addressed the complexities caused by those factors in 2 stages. Firstly, a Causal loop diagram was developed that illustated interrelationship between factors in the form of loops. Later SD model built, evaluated the combinatorial effect of 3 evolved stocks over the fourth stock Design Generated Waste-an emanating phenomenon. Simulation result revealed increasing trend of the stock DGW over a course of time. Therefore, increase in effect of complexities of behavior of design waste causes, will consequently lead to increase in DGW. Managing the complex behavior of these design causes will help control over the DGW w.r.t. time.

Performance evaluation of novel solarpowered domestic air cooler with Peltier modules

Zafar Abbas,A. N. Shah,M. Tahir Hassan,M. Sarfraz Ali,Qamar ud Din,Bilal Naseem,Ammar Asghar,Ali Haider 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.11

Shifting of air conditioning and ventilation plants from conventional to renewable energy systems is one of the effective ways to save energy and attain sustainability. In this experimental study, an effort has been made to design, fabricate, and evaluate the cooling performance of a solar-powered domestic air cooler with Peltier plates to meet the comfort criteria as per ASHRAE standards. It also investigates the effect of Peltier modules on the performance of conventional room air cooler. The experiments were conducted in a 12x12 room with one, two, three, and four Peltier modules operating at various ambient temperatures. The experiments were repeated three times at specified conditions. Peltier effect was used to decrease water temperature, and subsequently cooled water was used to decrease the temperature of the air after coming in contact with this water. The cooled air was then used to create a comfort zone. The results indicated a decrease in temperature of the experimental zone by 5 %, 13 %, 19 %, and 23 % using one, two, three, and four Peltier modules respectively. The increase in relative humidity was recorded as 5 % at 27 °C temperature of the experimental zone. The results of energy analysis showed a substantial amount of energy savings in this study and suggest that more than 200 MW energy can be saved by replacing conventional electric air coolers all over the country with proposed Peltier based domestic solar powered air cooler.

A Review of Synthesis, Characterization and Applications of Copper Nanoparticles Using Green Method

Muhammad Rafique,Ahson J. Shaikh,Reena Rasheed,Muhammad Bilal Tahir,Hafiz FaiqBakhat,MUHAMMAD SHAHID RAFIQUE,Faiz Rabbani 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.4

To address accosts of this modern age, the synthesis of metal nanoparticles is more important than ever. Copper has been recognized as a nontoxic, safe inorganic material, cheaper antibacterial/antifungal agent, and has high potential in a wide range of biological, catalytic and sensors applications more particularly in the form of nanoparticles. This resulted in the development of numerous methods for the synthesis of copper nanoparticles. As conventional methods like chemical and physical methods have several limitations so there is need to an alternate method. Due to nontoxic and eco-friendly nature, it has recently been shifted toward green synthesis of copper nanoparticles over conventional methods. Additionally, characterization of the synthesized nanoparticles is essential for their use in various applications. This review gives an overview of environment friendly synthesis method of copper nanoparticles and their applications on the basis of their potential selectivity and preferences in a number of fields like material sciences and biomedicine.

Additively manufactured nano-mechanical energy harvesting systems: advancements, potential applications, challenges and future perspectives

Ahmed Ammar,Azam Ali,Wang Yanen,Zhang Zutao,Li Ning,Jia Changyuan,Mushtaq Ray Tahir,Rehman Mudassar,Gueye Thierno,Shahid Muhammad Bilal,Basit Ali Wajid 나노기술연구협의회 2021 Nano Convergence Vol.8 No.37

Additively manufactured nano-MEH systems are widely used to harvest energy from renewable and sustainable energy sources such as wind, ocean, sunlight, raindrops, and ambient vibrations. A comprehensive study focusing on in-depth technology evolution, applications, problems, and future trends of specifically 3D printed nano-MEH systems with an energy point of view is rarely conducted. Therefore, this paper looks into the state-of-the-art technologies, energy harvesting sources/methods, performance, implementations, emerging applications, potential challenges, and future perspectives of additively manufactured nano-mechanical energy harvesting (3DP-NMEH) systems. The prevailing challenges concerning renewable energy harvesting capacities, optimal energy scavenging, power management, material functionalization, sustainable prototyping strategies, new materials, commercialization, and hybridization are discussed. A novel solution is proposed for renewable energy generation and medicinal purposes based on the sustainable utilization of recyclable municipal and medical waste generated during the COVID-19 pandemic. Finally, recommendations for future research are presented concerning the cutting-edge issues hurdling the optimal exploitation of renewable energy resources through NMEHs. China and the USA are the most significant leading forces in enhancing 3DP-NMEH technology, with more than 75% contributions collectively. The reported output energy capacities of additively manufactured nano-MEH systems were 0.5–32 mW, 0.0002–45.6 mW, and 0.3–4.67 mW for electromagnetic, piezoelectric, and triboelectric nanogenerators, respectively. The optimal strategies and techniques to enhance these energy capacities are compiled in this paper. Graphical Abstract

Comparison of hepatic MDCT, MRI, and DSA to explant pathology for the detection and treatment planning of hepatocellular carcinoma

( Lauren M. Ladd ),( Temel Tirkes ),( Mark Tann ),( David M Agarwal ),( Matthew S Johnson ),( Bilal Tahir ),( Kumaresan Sandrasegaran ) 대한간학회 2016 Clinical and Molecular Hepatology(대한간학회지) Vol.22 No.4

Background/Aims: The diagnosis and treatment plan for hepatocellular carcinoma (HCC) can be made from radiologic imaging. However, lesion detection may vary depending on the imaging modality. This study aims to evaluate the sensitivities of hepatic multidetector computed tomography (MDCT), magnetic resonance imaging (MRI), and digital subtraction angiography (DSA) in the detection of HCC and the consequent management impact on potential liver transplant patients. Methods: One hundred and sixteen HCC lesions were analyzed in 41 patients who received an orthotopic liver transplant (OLT). All of the patients underwent pretransplantation hepatic DSA, MDCT, and/or MRI. The imaging results were independently reviewed retrospectively in a blinded fashion by two interventional and two abdominal radiologists. The liver explant pathology was used as the gold standard for assessing each imaging modality. Results: The sensitivity for overall HCC detection was higher for cross-sectional imaging using MRI (51.5%, 95% confidence interval [CI]=36.2-58.4%) and MDCT (49.8%, 95% CI=43.7-55.9%) than for DSA (41.7%, 95% CI=36.2-47.3%) (P=0.05). The difference in false-positive rate was not statistically significant between MRI (22%), MDCT (29%), and DSA (29%) (P=0.67). The sensitivity was significantly higher for detecting right lobe lesions than left lobe lesions for all modalities (MRI: 56.1% vs. 43.1%, MDCT: 55.0% vs. 42.0%, and DSA: 46.9% vs. 33.9%; all P<0.01). The sensitivities of the three imaging modalities were also higher for lesions ≥2 cm vs. <2 cm (MRI: 73.4% vs. 32.7%, MDCT: 66.9% vs. 33.8%, and DSA: 62.2% vs. 24.1%; all P<0.01). The interobserver correlation was rated as very good to excellent. Conclusions: The sensitivity for detecting HCC is higher for MRI and MDCT than for DSA, and so cross-sectional imaging modalities should be used to evaluate OLT candidacy. (Clin Mol Hepatol 2016;22:450-457)