Variability and Predictability of Summer Monsoon Rainfall over Pakistan

Adnan Muhammad,Khan Firdos,Rehman Nadia,Ali Shaukat,Hassan Sher Shah,Dogar Muhammad Mubashar,Mehmood Shahbaz,Hasson Shabehul 한국기상학회 2021 Asia-Pacific Journal of Atmospheric Sciences Vol.57 No.1

Rainfall variability associated with the South Asian Summer Monsoon has increased in recent decades, particularly at the northwestern monsoon margins over Pakistan, leading to more frequent and intense hydro-meteorological extremes that have adversely affected the agrarian economy, water and food security in the country. Devising effective strategies to ensure sustainable development in Pakistan thus requires that the monsoonal rainfall be predicted on an inter-annual scale. Here, we predicted the inter- and intra-annual variability of the monsoonal rainfall over Pakistan and its possible drivers using a linear statistical forecast model of the principal component (PC) regression analysis. For this purpose, highly correlated PCs of the National Centre for Environmental Prediction (NCEP) based sea level pressure, horizontal and meridional winds to the observed rainfall for the period 2001–2013 were ingested in a stepwise multiple regression model, which was further validated for the duration of 2014–2015. Our results suggest that featuring correlation coefficient, mean absolute error, mean bias, and root mean square error of 0.75, 42.23, −14.92 and 60.65, respectively, the model exhibits robust skill in predicting the inter-annual monsoonal rainfall variability at its extreme northwestern margins over Pakistan.

Object Tracking With A Robotic Manipulator Mounted On Ground Vehicle Using Image Based Visual Servoing

Muhammad Ahsan Sami,Muhammad Umar Masood,Muhammad Waqar,Muhammad Mujtaba,Abrahim Ali Shah,Nasir Rashid,Mohsin I. Tiwana,Javaid Iqbal,Adnan Shujah 제어로봇시스템학회 2017 제어로봇시스템학회 국제학술대회 논문집 Vol.2017 No.10

This paper presents an application of a novel approach for detecting and tracking an object with a 2 DOF robotic manipulator which can be equipped with an array of electrically controlled actuators. The said approach utilizes the Image Based Visual Servoing (IBVS) technique. The developed system is able to determine the object pose in real time from features in the image. Object is detected using shaped based approach algorithms of image processing. The position and orientation of the world coordinates of the object being tracked are calculated from the coordinates of the object in image plane using camera’s intrinsic and extrinsic parameters. Experimental results demonstrate the effectiveness of this proposed approach.

Synthesis of novel <i>N</i>-(1,3-thiazol-2-yl)benzamide clubbed oxadiazole scaffolds: Urease inhibition, Lipinski rule and molecular docking analyses

Athar Abbasi, Muhammad,Raza, Hussain,Aziz-ur-Rehman, Hussain,Zahra Siddiqui, Sabahat,Adnan Ali Shah, Syed,Hassan, Mubashir,Seo, Sung-Yum Elsevier 2019 Bioorganic chemistry Vol.83 No.-

<P><B>Abstract</B></P> <P>Present work aimed to synthesize some unique bi-heterocyclic benzamides as lead compounds for the <I>in vitro</I> inhibition of urease enzyme, followed by <I>in silico</I> studies. These targeted benzamides were synthesized in good yields through a multi-step protocol and their structures were confirmed by IR, <SUP>1</SUP>H NMR, <SUP>13</SUP>C NMR, EI-MS and elemental analysis. The <I>in vitro</I> screening results showed that most of the ligands exhibited good inhibitory potentials against the urease. Chemo-informatics analysis envisaged that all these compounds obeyed the Lipinski's rule. Molecular docking results showed that <B>7h</B> exhibited good binding energy value (−8.40 kcal/mol) and was bound within the active region of urease enzyme. From the present investigation, it was inferred that some of these potent urease inhibitors might serve as novel templates in drug designing.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis of bi-heterocyclic scaffolds. </LI> <LI> Structural characterization with spectral analysis. </LI> <LI> Urease inhibition and structure-activity relationship. </LI> <LI> Chemo-informatics and validation of Lipinski rule. </LI> <LI> Molecular docking analysis to ascertain interactions. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Synthesis, <i>in vitro</i> and <i>in silico</i> studies of novel potent urease inhibitors: <i>N</i>-[4-({5-[(3-Un/substituted-anilino-3-oxopropyl)sulfanyl]-1,3,4-oxadiazol-2-yl}methyl)-1,3-thiazol-2-yl]benzamides

Abbasi, Muhammad Athar,Hassan, Mubashir,Aziz-ur-Rehman, Mubashir,Siddiqui, Sabahat Zahra,Raza, Hussain,Shah, Syed Adnan Ali,Seo, Sung-Yum Elsevier 2018 Bioorganic & medicinal chemistry Vol.26 No.13

<P><B>Abstract</B></P> <P>The present article describes the synthesis, <I>in vitro</I> urease inhibition and <I>in silico</I> molecular docking studies of a novel series of bi-heterocyclic bi-amides. The synthesis of title compounds was initiated by benzoylation, with benzoyl chloride (<B>1</B>), of the key starter ethyl 2-(2-amino-1,3-thiazol-4-yl)acetate (<B>2</B>) in weak basic aqueous medium followed by hydrazide formation, <B>4</B>, and cyclization with CS<SUB>2</SUB> to reach the parent bi-heterocyclic nucleophile, <I>N</I>-{4-[(5-sulfanyl-1,3,4-oxadiazol-2-yl)methyl]-1,3-thiazol-2-yl}benzamide (<B>5</B>). Various electrophiles, <B>8a–l</B>, were synthesized by a two-step process and these were finally coupled with <B>5</B> to yield the targeted bi-heterocyclic bi-amide molecules, <B>9a–l</B>. The structures of the newly synthesized products were corroborated by IR, <SUP>1</SUP>H NMR, <SUP>13</SUP>C NMR, EI-MS and elemental analysis. The <I>in vitro</I> screening of these molecules against urease explored that most of the compounds exhibit potent inhibitory potential against this enzyme. The compound <B>9j</B>, with IC<SUB>50</SUB> value of 2.58 ± 0.02 µM, exhibited most promising inhibitory activity among the series, relative to standard thiourea having IC<SUB>50</SUB> value of 21.11 ± 0.12 µM. <I>In silico</I> studies fully augmented the experimental enzyme inhibition results. Chemo-informatics analysis showed that synthesized compounds (<B>9a–l</B>) mostly obeyed the Lipinski's rule. Molecular docking study suggested that ligand <B>9j</B> exhibited good binding energy value (−7.10 kcal/mol) and binds within the active region of target protein. So, on the basis of present investigation, it was inferred that <B>9j</B> may serve as a novel scaffold for designing more potent urease inhibitors.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Synthesis and structure-activity relationship of tyrosinase inhibiting novel bi-heterocyclic acetamides: Mechanistic insights through enzyme inhibition, kinetics and computational studies

Butt, Abdul Rehman Sadiq,Abbasi, Muhammad Athar,Aziz-ur-Rehman, Muhammad Athar,Siddiqui, Sabahat Zahra,Raza, Hussain,Hassan, Mubashir,Shah, Syed Adnan Ali,Shahid, Muhammad,Seo, Sung-Yum Elsevier 2019 Bioorganic chemistry Vol.86 No.-

<P><B>Abstract</B></P> <P>The present research was designed for the selective synthesis of novel bi-heterocyclic acetamides, <B>9a-n</B>, and their tyrosinase inhibition to overwhelm the problem of melanogenesis. The structures of newly synthesized compounds were confirmed by spectral techniques such as <SUP>1</SUP>H NMR, <SUP>13</SUP>C NMR, and EI-MS along with elemental analysis. The inhibitory effects of these bi-heterocyclic acetamides (<B>9a-n</B>) were evaluated against tyrosinase and all these molecules were recognized as potent inhibitors relative to the standard used. The Kinetics mechanism was analyzed by Lineweaver-Burk plots which explored that compound, <B>9h</B>, inhibited tyrosinase competitively by forming an enzyme-inhibitor complex. The inhibition constants K<I> <SUB>i</SUB> </I> calculated from Dixon plots for this compound was 0.0027 µM. The computational study was coherent with the experimental records and these ligands exhibited good binding energy values (kcal/mol). The hemolytic analysis revealed their mild cytotoxicity towards red blood cell membranes and hence, these molecules can be pondered as nontoxic medicinal scaffolds for skin pigmentation and related disorders.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis of novel bi-heterocyclic acetamides and their tyrosinase inhibition to overwhelm the problem of melanogenesis. </LI> <LI> <I>In vitro</I> and <I>in silico</I> analysis were performed to check their inhibitory potential against tyrosinase enzymes. </LI> <LI> The molecules with small sized methyl group/s at <I>ortho</I>-position/s in aryl part or a flexible phenethyl group, generally inhibited the tyrosinase in an excellent manner. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Exploration of synthetic multifunctional amides as new therapeutic agents for Alzheimer's disease through enzyme inhibition, chemoinformatic properties, molecular docking and dynamic simulation insights

Hassan, Mubashir,Abbasi, Muhammad Athar,Aziz-ur-Rehman, Muhammad Athar,Siddiqui, Sabahat Zahra,Hussain, Ghulam,Shah, Syed Adnan Ali,Shahid, Muhammad,Seo, Sung-Yum Elsevier 2018 Journal of theoretical biology Vol.458 No.-

<P><B>Abstract</B></P> <P>A new series of multifunctional amides has been synthesized having moderate enzyme inhibitory potentials and mild cytotoxicity. 2-Furyl(1-piperazinyl)methanone (<B>1</B>) was coupled with 3,5-dichloro-2-hydroxybenzenesulfonyl chloride (<B>2</B>) to form {4-[(3,5-dichloro-2-hydroxyphenyl)sulfonyl]-1-piperazinyl}(2-furyl)methanone (<B>3</B>). Different elecrophiles were synthesized by the reaction of various un/substituted anilines (<B>4a-o</B>) with 2-bromoacetylbromide (<B>5</B>), 2‑bromo‑<I>N</I>-(un/substituted-phenyl)acetamides (<B>6a-o</B>). Further, equimolar ratios of <B>3</B> and <B>6a-o</B> were allowed to react in the presence of K<SUB>2</SUB>CO<SUB>3</SUB> in acetonitrile to form desired multifunctional amides (<B>7a-o</B>). The structural confirmation of all the synthesized compounds was carried out by their EI-MS, IR, <SUP>1</SUP>H NMR and <SUP>13</SUP>C NMR spectral data. Enzyme inhibition activity was performed against acetyl and butyrylcholinestrase enzymes, whereby <B>7e</B> showed very good activity having IC<SUB>50</SUB> value of 5.54 ± 0.03 and 9.15 ± 0.01 <I>μ</I>M, respectively, relative to eserine, a reference standard. Hemolytic activity of the molecules was checked to asertain their cytotoxicity towards red blood cell membrance and it was observed that most of the compounds were not toxic up to certain range. Moreover, chemoinformatic protepties and docking simulation results also showed the significance of <B>7e</B> as compared to other compounds. Based on <I>in vitro</I> and <I>in silico</I> analysis <B>7e</B> could be used as a template for the development of new drugs against Alzheimer's disease.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Designing of multifunctional amides derivatives as acetyl and butyrylcholinesterase inhibitors. </LI> <LI> Chemoinformatic, molecular docking and simulation analysis was against most potent inhibitor <B>7e.</B> </LI> <LI> In vitro and in silico results showed the significance of <B>7e</B> and could be used as a template for novel drugs against Alzheimer's disease. </LI> </UL> </P>

Designing of promising medicinal scaffolds for Alzheimer’s disease through enzyme inhibition, lead optimization, molecular docking and dynamic simulation approaches

Hassan, Mubashir,Abbasi, Muhammad Athar,Aziz-ur-Rehman, Muhammad Athar,Siddiqui, Sabahat Zahra,Shahzadi, Saba,Raza, Hussain,Hussain, Ghulam,Shah, Syed Adnan Ali,Ashraf, Muhamamd,Shahid, Muhammad,Seo, Academic Press 2019 Bioorganic chemistry Vol.91 No.-

<P><B>Abstract</B></P> <P>In the designed research work, a series of 2-furoyl piperazine based sulfonamide derivatives were synthesized as therapeutic agents to target the Alzheimer’s disease. The structures of the newly synthesized compounds were characterized through spectral analysis and their inhibitory potential was evaluated against butyrylcholinesterase (BChE). The cytotoxicity of these sulfonamides was also ascertained through hemolysis of bovine red blood cells. Furthermore, compounds were inspected by Lipinki Rule and their binding profiles against BChE were discerned by molecular docking. The protein fluctuations in docking complexes were recognized by dynamic simulation. From our <I>in vitro</I> and <I>in silico</I> results <B>5c</B>, <B>5j</B> and <B>5k</B> were identified as promising lead compounds for the treatment of targeted disease.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Sulfonamide derivatives were synthesized as therapeutic agents to target the Alzheimer’s disease. </LI> <LI> The inhibitory potential of newly synthesized compounds were evaluated against butyrylcholinesterase (BChE). </LI> <LI> The cytotoxicity of these sulfonamides was also ascertained through hemolysis of bovine red blood cells. </LI> <LI> Computational analysis was performed to check their binding profile against target protein. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

2-Furoic piperazide derivatives as promising drug candidates of type 2 diabetes and Alzheimer’s diseases: <i>In vitro</i> and <i>in silico</i> studies

Abbasi, Muhammad Athar,Hassan, Mubashir,ur-Rehman, Aziz,Siddiqui, Sabahat Zahra,Hussain, Ghulam,Shah, Syed Adnan Ali,Ashraf, Muhammad,Shahid, Muhammad,Seo, Sung Yum Elsevier 2018 Computational biology and chemistry Vol.77 No.-

<P><B>Abstract</B></P> <P>The heterocyclic compounds have been extensively reported for their bioactivity potential. The current research work reports the synthesis of some new multi-functional derivatives of 2-furoic piperazide (<B>1</B>; 1-(2-furoyl)piperazine). The synthesis was initiated by reacting the starting compound <B>1</B> with 3,5-dichloro-2-hydroxybenzenesulfonyl chloride (<B>2</B>) in a basic, polar and protic medium to obtain the parent sulfonamide <B>3</B> which was then treated with different electrophiles, <B>4a–g</B>, in a polar and aprotic medium to acquire the designed molecules, <B>5a</B>–<B>g</B>. These convergent derivatives were evaluated for their inhibitory potential against <I>α</I>-glucosidase, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Acarbose was used as a reference standard for <I>α</I>-glucosidase inhibition while eserine for AChE and BChE inhibition. Some of the synthesized compounds were identified as promising inhibitors of these three enzymes and their bioactivity potentials were also supported by molecular docking study. The most active compounds among the synthetic analogues might be helpful in drug discovery and development for the treatment of type 2 diabetes and Alzhiemer’s diseases.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis of multi-functional 2-furoic piperazide derivatives. </LI> <LI> Enzyme inhibitory studies against different enzymes. </LI> <LI> Computational studies to augment the <I>in vitro</I> results. </LI> <LI> Suitable therapeutic agents for type 2 diabetes and Alzheimer’s disease. </LI> <LI> Mild hemolytic agents toward red blood cell membrane. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>