19 research outputs found

    Sol-Gel to Prepare Nickel Doped TiO2 Nanoparticles for Photocatalytic Treatment of E 131 VF Food Dye Wastewater

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    Sol–gel method was applied for synthesis of TiO2 nanoparticles in the existence of different volumes of ethanol (10–50 mL) with the purpose to find optimized synthesis conditions. Also, nickel doped TiO2 nanoparticles (Ni/TiO2 molar ratio: 0.1-1.0%) were prepared by the similar technique but in the existence of 10 mL ethanol and heated at different temperatures (300 °C –600 °C). XRD, SEM/EDX, UV-Vis DRS, FTIR and Raman spectroscopy were applied to identify the structural and morphological characteristics of the as-synthesized samples. XR diffraction results verified that TiO2 samples prepared with various volumes of ethanol (10–50 mL) consist of anatase and brookite phases up to 500 °C and rutile phase at 600 °C. The intensity of brookite diffraction decreased with the increase of calcination temperatures. Also, the low ethanol volume favored for formation of rutile phase at 600 °C. The addition of Ni(II) during the preparation of TiO2 nanoparticles prevented the formation of rutile phase. The undoped samples were synthesized with 10 and 20 mL ethanol and treated at 500 °C displayed the best catalytic performance for photocatalytic treatment of E 131 VF dye solution (rate constant: 0.051 and 0.061 (a.u) respectively). Ni doped TiO2 samples displayed lower photoactivity and rate constant

    Asymmetric synthesis of lactams mediated by copper(I) complexes

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    The asymmetric synthesis of ÎČ- and Îł-lactams is a center of interest for chemists due to their biological and pharmaceutical applications. The asymmetric and diastereoselective synthesis of ÎČ-lactams through Kinugasa reaction, a (3+2) cycloaddtion reaction between a nitrone and a terminal alkyne and catalyzed by copper(I) complexes is studied. A diastereoselective version of this reaction is developed using NHC copper catalysts. An asymmetric version of this reaction is studied as well. Furthermore, a double Michael domino cyclization process catalyzed by a copper(I) catalyst is examined. This methodology allows the formation of Îł-and ÎŽ-lactams in one step. Starting from substrates comprising two Michael acceptors, a double Michael addition mechanism is expected to form the desired products. The same substrates are also subjected to Morita-Baylis-Hilman reaction conditions to provide α-methylene-Îł-lactams which present an interesting class of compounds with important biological activities. Besides, an illustration of a synthetic pathway to produce unprecedented dinuclear copper acetylide diphosphine complexes is demonstrated. These complexes are present with one phosphine of a given ligand bridging to one copper atom while the other phosphine bridges to the other copper atom.(SC - Sciences) -- UCL, 201

    PÄ tal om studie- och yrkesvÀgledare

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    Syftet med studien Àr att undersöka studie- och yrkesvÀgledares upplevelse av vÀgledaruppdraget och den egna yrkesrollen pÄ grundskolan. Tidigare forskning om studie- och yrkesvÀgledning i bÄde vid och snÀv bemÀrkelse visar att studie- och yrkesvÀgledarens roll kan framstÄ som otydlig, men ocksÄ som en roll som pÄverkar elevernas uppfattningar om uppdraget. Vi har anvÀnt oss av kvalitativ metod dÄ vi utfört sex semistrukturerade intervjuer enligt studiens frÄgestÀllningar: Hur uppfattar studie- och yrkesvÀgledare sitt uppdrag pÄ grundskolan? Hur tÀnker studie- och yrkesvÀgledare kring studie- och yrkesvÀgledning som hela skolans ansvar? Hur upplever studie- och yrkesvÀgledare sin yrkesroll pÄ den egna grundskolan? The Organization as a Systems of Roles som en del av The Social Psycology of Organizations Theory (Katz & Kahn, 1987) utgör arbetets teoretiska grund. Tre aspekter pÄ studie- och yrkesvÀgledarens uppdrag kan plockas ut. Första aspekten handlar om de organisatoriska faktorerna i form av styrdokument för uppdragets funktion och mÄl. Andra aspekten handlar om samverkan i vid bemÀrkelse i relation till aktiviteterna och ansvarsfördelning. Den tredje aspekten handlar om vÀgledarens uppfattning om den egna positionen inom uppdraget som skulle kunna beskrivas som en önskan för ett tydligt mandat inför andra yrkesroller pÄ den egna grundskolan. Studien tyder pÄ att vÀgledaren aktivt skapa sin roll i relation till egna och andras förvÀntningar samt förutsÀttningar pÄ grundskolan. Det sÀtter den personliga prÀgeln pÄ vÀgledarnas sÀtt att arbeta och kan ses som ett uttryck för hÄllbarhet och ömtÄlighet av uppdraget i vid och snÀv bemÀrkelse pÄ grundskolan

    PÄ tal om studie- och yrkesvÀgledare

    No full text
    Syftet med studien Àr att undersöka studie- och yrkesvÀgledares upplevelse av vÀgledaruppdraget och den egna yrkesrollen pÄ grundskolan. Tidigare forskning om studie- och yrkesvÀgledning i bÄde vid och snÀv bemÀrkelse visar att studie- och yrkesvÀgledarens roll kan framstÄ som otydlig, men ocksÄ som en roll som pÄverkar elevernas uppfattningar om uppdraget. Vi har anvÀnt oss av kvalitativ metod dÄ vi utfört sex semistrukturerade intervjuer enligt studiens frÄgestÀllningar: Hur uppfattar studie- och yrkesvÀgledare sitt uppdrag pÄ grundskolan? Hur tÀnker studie- och yrkesvÀgledare kring studie- och yrkesvÀgledning som hela skolans ansvar? Hur upplever studie- och yrkesvÀgledare sin yrkesroll pÄ den egna grundskolan? The Organization as a Systems of Roles som en del av The Social Psycology of Organizations Theory (Katz & Kahn, 1987) utgör arbetets teoretiska grund. Tre aspekter pÄ studie- och yrkesvÀgledarens uppdrag kan plockas ut. Första aspekten handlar om de organisatoriska faktorerna i form av styrdokument för uppdragets funktion och mÄl. Andra aspekten handlar om samverkan i vid bemÀrkelse i relation till aktiviteterna och ansvarsfördelning. Den tredje aspekten handlar om vÀgledarens uppfattning om den egna positionen inom uppdraget som skulle kunna beskrivas som en önskan för ett tydligt mandat inför andra yrkesroller pÄ den egna grundskolan. Studien tyder pÄ att vÀgledaren aktivt skapa sin roll i relation till egna och andras förvÀntningar samt förutsÀttningar pÄ grundskolan. Det sÀtter den personliga prÀgeln pÄ vÀgledarnas sÀtt att arbeta och kan ses som ett uttryck för hÄllbarhet och ömtÄlighet av uppdraget i vid och snÀv bemÀrkelse pÄ grundskolan

    Gene expression profiling of circulating CD133+ cells of hepatocellular carcinoma patients associated with HCV infection

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    Aim: Identifying the genetic expression profile of CD133+ cells from HCC patients compared to CD133+ cells from healthy volunteers that may contribute in hepatocarcinogenesis process. Method: Circulating CD133+ cells were sorted from the peripheral blood of HCC patients as well as from healthy volunteers using magnetic activated cell sorting. The differential expression profile of stem cell related genes was performed using the Stem Cell PCR profiling assay. Results: Data analysis of stem cells related genes in CD133+ cells of the HCC group compared to the control group showed that; CCND2, COL1A1, CTNNA1, DLL3, JAG1, KRT15, MYC, NOTCH2, T and TERT were up-regulated (fold change = 80, 68.6, 6.67, 7.22, 3.8, 15.2, 14.5, 105.6, 26.6 and 99 respectively while only CD3D was down-regulated (fold change = 0.055) in HCC patients. However, after application of Beferroni correction to adjust P-value; KRT15 was the only gene that was significantly over expressed in CD133+ cells of HCC compared to control group (P-value = 0.012). Conclusion: KRT15 can be used to differentiate between circulating CD133+ cells from HCC group and control group. However, further study may be needed to confirm on the protein level

    The Different Types of Metallophores Produced by <i>Salmonella enterica</i>: A Review

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    Salmonella enterica (S. enterica) serovars Enteritidis and Typhimurium are the main causes of bacterial gastroenteritis worldwide. This Gram-negative rods bacterium possesses several virulence factors that enable it to survive the host’s nutritional immunity. Toxins and metallophores are among these factors. Heavy metals, in particular, are essential for the survival of all living organisms including bacteria. During infection, S. enterica competes with the host for the available heavy metals by secreting metallophores, which are secondary metabolites. Once produced in the extracellular medium, metallophores complex heavy metals thus allowing Salmonella to acquire metal ions through importing them via channels embedded in their membranes. This review highlights the biosynthesis, export, import, and genetic regulation of different metallophores synthesized by this germ

    Cyclodextrins and Amino Acids Enhance Solubility and Tolerability of Retinoic Acid/Tretinoin: Molecular Docking, Physicochemical, Cytotoxicity, Scratch Assay, and Topical Gel Formulations Investigation

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    With increasing longevity globally, the search for effective and patient-friendly anti-aging solutions has been growing. Retinoic acid (Ret) is an FDA-approved anti-aging and anti-wrinkling formula, however, its poor solubility and poor tolerability hamper its use in cosmetically accepted formulations. In this study, cyclodextrins and arginine were investigated for improving the solubility and tolerability of retinoic acid through the formation of inclusion complexes and salt formation, respectively. Two different methods were employed: physical mixing and kneading. The prepared dispersions were investigated for molecular docking (MD), solubility, thermal and spectral analyses, cytotoxicity, and scratch assays. The optimized disperse systems were formulated in a gel formulation and characterized for rheological, in vitro release, and kinetics. The MD, DSC, and FTIR results indicated that both ÎČ- and hydroxy propyl (HP) ÎČ-cyclodextrins could host RA in their cavities and form inclusion complexes. Ret can form a salt with the basic amino acid arginine. Solubility studies of RA significantly (p p < 0.05) reduce the irritation potential of Ret. Furthermore, comparable gap closure rates were recorded for Ret alone, Ret:HP ÎČ-CD K, and Ret:arginine K, indicating that inclusion complexation and ion pair formation reduced the irritation potentials without undermining the efficacy
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