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Transparent conductive oxides such as indium tin oxide (ITO) substrates are commonly employed as prime materials for optoelectronic applications. Enhancement in functions of such devices often compels stable and robust modification of the ITO substrate to improve its interfacial charge transfer characteristics. Thereby, in this work, naphthyl modifier multilayer films are fabricated on LTO substrate using conventional electrochemical reduction of 1-naphthyl diazonium salts (NAPH-D) via altering its concentration ranging from 2 mM to 12 mM with a step size of 2. Surface coverage was significantly tuned by varying NAPH-D concentration, keeping other parameters such as the number of scans and scan rate constant. For lower concentrations (2 mM), the molecular thickness ~6 nm was obtained, whereas higher concentrations (12 mM) produced around 15-18 nm thickness. Atomic force microscopy (AFM), cyclic voltammetry, and electrochemical impedance spectroscopy (EIS) in the presence of a ferrocene redox probe also supports the formation of well packed molecular film grown on the ITO surface. Further, the wettability property of the grafted naphthyl film was investigated at different surface coverages and correlated with charge transfer resistance ([R.sub.Ct]) obtained from EIS studies. Key words: electrochemical grafting, naphthyl diazonium salts, multilayer film, surface coverage, charge transfer resistance. Les oxydes conducteurs transparents tels que les substrats d'oxyde d'indium-etain (aussi appele ITO pour l'anglais indium-tin oxide) sont couramment utilises comme matieres premieres dans les dispositifs optoelectroniques. L'extension des fonctionnalites de ces dispositifs requiert souvent une modification stable et robuste du substrat d'ITO dans le but d'ameliorer ses caracteristiques de transfert de charge interfacial. Ainsi, dans le cadre des presents travaux, nous avons fabrique des films multicouches modifies par des groupes naphtyles sur un substrat d'lTO par reduction electrochimique classique de sels de 1-naphtyldiazonium (NAPH-D), en faisant passer leur concentration de 2 mM a 12 mM par increments de 2 mM. Nous avons regie avec une precision substantielle le recouvrement de la surface en faisant varier la concentration de NAPH-D, tout en maintenant constants d'autres parametres tels que le nombre de balayages et la vitesse de balayage. [Angstrom] la concentration la plus faible (2 mM), nous avons obtenu un film d'epaisseur moleculaire, soit environ 6 nm, tandis qu'a la concentration la plus elevee (12 mM), nous avons obtenu un film d'environ 15 a 18 nm d'epaisseur. La microscopie a force atomique (AFM), la voltamperometrie cyclique et la spectroscopic d'impedance electrochimique (SIE) en presence d'une sonde redox a base de ferrocene appuient egalement la formation bien compacte de films moleculaires et leur croissance a partir de la surface d'lTO. En outre, nous avons etudie la mouillabilite du film de naphtyle greffe a differents degres de recouvrement de la surface et nous l'avons mis en correlation avec la resistance au transfert de charge ([R.sub.tc]) obtenue a partir des analyses de SIE. [Traduit par la Redaction] Mots-cles: greffage electrochimique, sels de naphtyldiazonium, film multicouche, recouvrement de surface, resistance au transfert de charge., 1. Introduction Indium tin oxide (LTO) is an important n-type transparent conductive oxide (TCO) having wide applications in several optoelectronic devices such as organic light-emitting diodes, (1-3) photovoltaics, (4-6) solar [...]

Summary: Cold shock proteins are characterized by the presence of one or more cold shock domains that bestow them with nucleic acid binding ability. Although cold shock proteins are well characterized in bacteria, plants and humans, there is no information on their existence and role in malaria parasite. Here, we have identified and delineated the function of a cold shock protein of Plasmodium falciparum (Pf) ‘PfCoSP’. We demonstrate that PfCoSP exhibits nucleic acid binding properties and regulates gene expression. PfCoSP promotes microtubule assembly by interacting with Pf α/β tubulin. We identified a human cold shock protein LIN28A inhibitor ‘LI71’ as a binding partner of PfCoSP which inhibited PfCoSP–DNA and α/β tubulin interactions and, also inhibited the development of asexual blood stages and gametocyte stage of malaria parasite. Because PfCoSP is essential for parasite survival, characterization of its interacting partners may form the basis for development of future anti-malarials.

In this study, the computer simulation is carried out using FORTRAN to develop a theoretical model for estimating the lubrication performance of an elliptic bore journal bearing. The Analysis initially includes the hydrodynamic lubrication principle to solve non-dimensional Reynold’s equation of a finite journal bearing for bearing pressure. Subsequently, the load-carrying capacity, friction force, and lubricant flow are studied for different bearing eccentricities, non-circularity, and surface roughness parameters. The model thus developed, shows a good agreement with available research work. The results predict non-circularity up to (G=1.0) promotes better load-bearing ability, while roughness index (Y=0.1), offers the highest fluid friction. The highest non-dimensional load, friction, and flow-in are found to be 31.12, 45.19, and 6.42 respectively. The optimization shows the favorable condition for low, medium, and high load, friction, and flow-in.