Tailoring metal–oxide interfaces of inverse catalysts of TiO₂/nanoporous-Au under hydrogen oxidation

Qadir, Kamran,Quynh, Bui Thi Phuong,Lee, Hyosun,Moon, Song Yi,Kim, Sang Hoon,Park, Jeong Young The Royal Society of Chemistry 2015 Chemical communications Vol.51 No.47

<P>Engineering metal-oxide interfaces in TiO2/nanoporous (np) Au inverse catalysts results in enhancement of H-2 oxidation activity. While the intrinsic activity of the novel np-Au prepared from a Au-Si alloy is low, the activity increased as the weight fraction of the TTIP (amount of TiO2) was increased to 0.5 weight%. We correlate the change in activity with the active sites at the perimeter interface between the TiO2 and np-Au.</P>

Modified relativistic dynamics

Qadir, Asghar,Lee, Hyung Won,Kim, Kyoung Yee World Scientific Publishing Company 2017 International Journal of Modern Physics D Vol.26 No.5

<P>One of the major problems in Cosmology is the fact that there is no good candidate of dark matter in the Standard Model of Particle Physics or any experimentally supported modifications of it. At the same time, one of the major problems of General Relativity is that it cannot be unified with Quantum Theory. Here, we present a program to see if there is not a common source of both problems. The idea is that an interaction term between matter fields and the gravitational field in the total Lagrangian, analogous to that for Electromagnetism, could possibly provide the dynamical effect for which the dark matter is postulated, on the one hand and a Quantum-Field Theory (QFT) incorporating Gravity, that does not have unmanageable divergences, on the other. One could first check that the modified relativistic dynamics, if fitted for the dark matter in individual galaxies fits also for systems and clusters of galaxies, at all scales. If there is no problem with the explanation of the dynamics usually explained by dark matter <I>at all scales</I>, we could check if it leads to a workable QFT of Relativity.</P>

Critical Impact Energy for Spalling, Tunnelling and Penetration of Concrete Slab impacted with Hard Projectile

Qadir Bux alias Imran Latif,Ismail Abdul Rahman,Ahmad Mujahid Ahmad Zaidi,Kamran Latif 대한토목학회 2015 KSCE JOURNAL OF CIVIL ENGINEERING Vol.19 No.1

Penetration is the basic element of designing protective concrete structure against the local impact damage of hard missile. Impactenergy is the dominant cause of damage in moving accidents. When hard projectile collides with concrete target, it is the impactenergy of the projectile that makes concrete target to deform. Therefore, it is vital to study critical impact energy required to causespenetration. An analytical model is developed to predict the required critical impact energy for maximum penetration without reareffects in concrete slabs when it is impacted with hard projectile. The nose shape factor Ni also has been introduced with inclusion ofempirical friction factor Nf, as modification in Chen & Li nose shape factor for ogive nose hard projectile. The newly developedanalytical model and nose shape factor Ni is examined for CRH = 2.0, CRH = 3.0, and CRH = 4.25. It was found that the predictedresults from analytical model with nose shape Ni are in close relation with experimental data in all cases as compared to predictedresults with traditional Li and Chen nose shape N*. In, General, the analytical model generates encouraging prediction which isconsistent and follows a general trend of experimental results.

Insulin suppresses distal-less homeobox 5 expression through the up-regulation of microRNA-124 in 3T3-L1 cells

Qadir, A.S.,Woo, K.M.,Ryoo, H.M.,Baek, J.H. Academic Press 2013 Experimental cell research Vol.319 No.14

Distal-less homeobox 5 (Dlx5) is a pro-osteogenic but anti-adipogenic transcription factor that regulates lineage commitment in mesenchymal stem cells. Although the expression of Dlx5 is known to be decreased by adipogenic stimuli, the mechanism of Dlx5 down-regulation has not yet been clarified. MicroRNAs (miRNAs) are small regulatory RNAs that post-transcriptionally regulate many biological functions, including cell differentiation. In this study, we examined whether miRNAs are involved in down-regulation of Dlx5 following adipogenic stimuli. We screened candidate miRNAs that have a direct target site in the Dlx5 3'UTR using computational prediction programs, selected seven miRNA candidates with the highest binding score and observed their expression levels in 3T3-L1 murine pre-adipocytes. Among the miRNAs examined, only miR-124 was significantly up-regulated by 24-h incubation in adipogenic medium. Among the four components of adipogenic stimuli (1-methy-3-isobutyl xanthine, insulin, indomethacin and dexamethasone), insulin exhibited the highest stimulatory effect on miR-124 expression. Insulin significantly increased the expression of miR-124 precursors including pri-miR-124-1, pri-miR124-2 and pri-miR-124-3. LY294002, an inhibitor of phosphatidylinositol-3-kinase, prevented the regulatory effect of insulin on the expression levels of miR-124 and Dlx5. Over-expression of a miR-124 mimic decreased the expression of Dlx5 while increasing adipogenic differentiation in 3T3-L1 cells. Blocking miR-124 with anti-miR-124, a hairpin inhibitor of miR-124, increased the expression level of Dlx5 and suppressed adipogenic differentiation. When reporter assays were performed with a reporter construct containing the Dlx5 3'UTR sequence downstream of a luciferase gene, miR-124 mimic suppressed, but anti-miR-124 enhanced, luciferase activity in an miR-124 binding site-dependent manner. These results suggest that insulin-induced miR-124 plays a pivotal role in post-transcriptional regulation of Dlx5 during adipogenic differentiation and that miR-124 exerts pro-adipogenic effects by targeting Dlx5, at least in part.

Intrinsic Relation between Catalytic Activity of CO Oxidation on Ru Nanoparticles and Ru Oxides Uncovered with Ambient Pressure XPS

Qadir, Kamran,Joo, Sang Hoon,Mun, Bongjin S.,Butcher, Derek R.,Renzas, J. Russell,Aksoy, Funda,Liu, Zhi,Somorjai, Gabor A.,Park, Jeong Young American Chemical Society 2012 NANO LETTERS Vol.12 No.11

<P>Recent progress in colloidal synthesis of nanoparticles with well-controlled size, shape, and composition, together with development of in situ surface science characterization tools, such as ambient pressure X-ray photoelectron spectroscopy (APXPS), has generated new opportunities to unravel the surface structure of working catalysts. We report an APXPS study of Ru nanoparticles to investigate catalytically active species on Ru nanoparticles under oxidizing, reducing, and CO oxidation reaction conditions. The 2.8 and 6 nm Ru nanoparticle model catalysts were synthesized in the presence of poly(vinyl pyrrolidone) polymer capping agent and deposited onto a flat Si support as two-dimensional arrays using the Langmuir–Blodgett deposition technique. Mild oxidative and reductive characteristics indicate the formation of surface oxide on the Ru nanoparticles, the thickness of which is found to be dependent on nanoparticle size. The larger 6 nm Ru nanoparticles were oxidized to a smaller extent than the smaller Ru 2.8 nm nanoparticles within the temperature range of 50–200 °C under reaction conditions, which appears to be correlated with the higher catalytic activity of the bigger nanoparticles. We found that the smaller Ru nanoparticles form bulk RuO<SUB>2</SUB> on their surfaces, causing the lower catalytic activity. As the size of the nanoparticle increases, the core–shell type RuO<SUB>2</SUB> becomes stable. Such in situ observations of Ru nanoparticles are useful in identifying the active state of the catalysts during use and, hence, may allow for rational catalyst designs for practical applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2012/nalefd.2012.12.issue-11/nl303072d/production/images/medium/nl-2012-03072d_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl303072d'>ACS Electronic Supporting Info</A></P>

Effect of different extraction protocols on anticancer and antioxidant activities of Berberis koreana bark extracts

Qadir, S.A.,Kwon, M.C.,Han, J.G.,Ha, J.H.,Chung, H.S.,Ahn, J.,Lee, H.Y. Society for Bioscience and Bioengineering, Japan ; 2009 Journal of bioscience and bioengineering Vol.107 No.3

High-pressure extraction and ultrasonification extraction techniques were employed to extract bioactive compounds from Berberis koreana. This study aimed to determine the effect of ultrasonification in a high pressure process on the extraction yield, and the anticancer and antioxidant activities of the B. koreana bark extract. The effect of high-pressure extraction time when carried out for 5 and 15 min (HP5 and HP15) was also investigated. The best extraction yield with maximum percentage of phenolic compounds was obtained using high pressure with sonification (HPWS) extraction method. Experimental results indicated that HPWS altered the antioxidant activities, including the scavenging capacity of diphenylpicrylhydrazyl (DPPH) and xanthine oxidase. HP5 and HP15 with conventional extraction have almost similar bioactivity, but showed lower antioxidant and anticancer activities compared to HPWS. The results showed that the application of ultrasonification improved the extraction efficiency for bioactive compounds and, as deduced from chromatographic profiles, it may have allowed the release of new compounds. The scanning electron microscope (SEM) showed evidence of rupturing of the tissue surface treated with HPWS, in contrast to conventional extraction, HP5, and HP15. The HPWS extraction was not only more efficient but also convenient for the recovery and purification of the active compounds of hard plant tissues.

A Hybridized Disparity Computation Fusing Disparity Space Image and Multi Resolution Image Segmentation

Qadir, Mudasar,Soh, Youngsung,Ashraf, Hadi,Kim, Intaek IACSIT Press 2014 International journal of computer theory and engin Vol.6 No.5

Deactivation of Ru Catalysts under Catalytic CO Oxidation by Formation of Bulk Ru Oxide Probed with Ambient Pressure XPS

Qadir, Kamran,Kim, Sun Mi,Seo, Hyungtak,Mun, Bongjin S.,Akgul, Funda Aksoy,Liu, Zhi,Park, Jeong Young American Chemical Society 2013 The Journal of Physical Chemistry Part C Vol.117 No.25

<P>The surface science approach of using model catalysts in conjunction with the development of in situ spectroscopic tools, such as ambient pressure X-ray photoelectron spectroscopy (AP-XPS), offers a synergistic strategy for obtaining a substantially better understanding of deactivation phenomena. In this study, we investigated the nature of Ru oxides on a Ru polycrystalline film under oxidizing, reducing, and catalytic CO oxidation reaction conditions. Thus, bulk Ru oxide was easily formed on such Ru catalysts, the growth of which was dependent on reaction temperature. Once formed, such an oxide is irreversible and cannot be completely removed even under reducing conditions at elevated temperatures (200 °C). Our reaction studies showed substantial deactivation of the Ru film during catalytic CO oxidation, and its activity could be partially recovered after reduction pretreatment. Such continuous deactivation of a Ru film is correlated with irreversibly formed bulk Ru oxide, as shown by AP-XPS. Such in situ spectroscopic evidence of the transition of oxides to a catalytically inactive state can enable more effective design of catalysts with less deactivation.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2013/jpccck.2013.117.issue-25/jp402688a/production/images/medium/jp-2013-02688a_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp402688a'>ACS Electronic Supporting Info</A></P>

Curcumin: a Polyphenol with Molecular Targets for Cancer Control

Qadir, Muhammad Imran,Naqvi, Syeda Tahira Qousain,Muhammad, Syed Aun Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.6

Curcumin, is a polyphenol from Curcuma longa (turmeric plant), is a polyphenol that belongs to the ginger family which has long been used in Ayurveda medicines to treat various diseases such as asthma, anorexia, coughing, hepatic diseases, diabetes, heart diseases, wound healing and Alzheimer's. Various studies have shown that curcumin has anti-infectious, anti-inflammatory, anti-oxidant, hepatoprotective, thrombosuppressive, cardio protective, anti-arthritic, chemo preventive and anti-carcinogenic activities. It may suppress both initiation and progression stages of cancer. Anticancer activity of curcumin is due to negative regulation of inflammatory cytokines, transcription factors, protein kinases, reactive oxygen species (ROS) and oncogenes. This review focuses on the different targets of curcumin to treat cancer.

Novel Synthesis of Mannosamine Conjugated Magnetic Nanoparticles for Purification and Stabilization of Human Lysosomal β-mannosidase

Zahoor Qadir Samra,Muhammad Amin Athar 한국생물공학회 2009 Biotechnology and Bioprocess Engineering Vol.14 No.5

Abstract Human β-mannosidase (MANB) was purified to homogeneity directly from lysosomes by using mannosamine conjugated magnetic (Fe₃O₄) nanoparticles, DE-52 cellulose, and sephadex G-200 chromatography. Fe₃O₄nanoparticles were synthesized and utilized ammonia to attach the amino group on the nanoparticles. The particles were covalently attached with Dmannosamine by cross linker glutaraldehyde and confirmed by FTIR spectroscopy. In FTIR analysis, the peaks appeared at 2,356.6 cm−¹ for −N = CH linkage and at 3,378.4 cm−1, 3,664.9 cm−¹ for −OH groups confirmed the conjugation of Dmannosamine with Fe₃O₄ nanoparticles. Results showed a single band of 97 kDa of purified MANB in SDS-PAGE. The isoelectric point was 4.5 and the Km and Vã~ñ values were 2.51 mM and 0.315 μM/min/mg, respectively. The purification fold was 329 with 68% yield. The optimal activity was at pH 5.0 and 75% activity was stable in 20% glycerol at 4oC. The enzyme activity was inhibited by Ni²+, Zn²+, Cd²+, Cu²+, Mo²+, Ag+¹, iodoacetate, SDS, DMF, DMSO, ethanol, and acetone; slightly reduced by Pb²+, Co²+, EDTA, DTT, and β-mercaptoethanol. The activity was not affected by Mg²+, Mn²+, Sn²+, Ca²+, Fe³+, PMSF, Triton X-100, D-mannosamine, D-mannose, D-mannitol, D-glucose, and D-fructose. The homogeneity of MANB enzyme was further confirmed by 2D-PAGE and immunoblot. This is the first novel report of conjugation of Dmannosamine with Fe₃O₄nanoparticles for purification of human MANB enzyme Abstract Human β-mannosidase (MANB) was purified to homogeneity directly from lysosomes by using mannosamine conjugated magnetic (Fe₃O₄) nanoparticles, DE-52 cellulose, and sephadex G-200 chromatography. Fe₃O₄nanoparticles were synthesized and utilized ammonia to attach the amino group on the nanoparticles. The particles were covalently attached with Dmannosamine by cross linker glutaraldehyde and confirmed by FTIR spectroscopy. In FTIR analysis, the peaks appeared at 2,356.6 cm−¹ for −N = CH linkage and at 3,378.4 cm−1, 3,664.9 cm−¹ for −OH groups confirmed the conjugation of Dmannosamine with Fe₃O₄ nanoparticles. Results showed a single band of 97 kDa of purified MANB in SDS-PAGE. The isoelectric point was 4.5 and the Km and Vã~ñ values were 2.51 mM and 0.315 μM/min/mg, respectively. The purification fold was 329 with 68% yield. The optimal activity was at pH 5.0 and 75% activity was stable in 20% glycerol at 4oC. The enzyme activity was inhibited by Ni²+, Zn²+, Cd²+, Cu²+, Mo²+, Ag+¹, iodoacetate, SDS, DMF, DMSO, ethanol, and acetone; slightly reduced by Pb²+, Co²+, EDTA, DTT, and β-mercaptoethanol. The activity was not affected by Mg²+, Mn²+, Sn²+, Ca²+, Fe³+, PMSF, Triton X-100, D-mannosamine, D-mannose, D-mannitol, D-glucose, and D-fructose. The homogeneity of MANB enzyme was further confirmed by 2D-PAGE and immunoblot. This is the first novel report of conjugation of Dmannosamine with Fe₃O₄nanoparticles for purification of human MANB enzyme