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A property of central interest for theoretical study of nanoconfined fluids is the density distribution of molecules. The density profile of the hard-sphere fluids confined within nanoslit pores is a key quantity for understanding the configurational behavior of confined real molecules. In this report, we produce the density profile of the hard-sphere fluid confined within nanoslit pores using the fundamental-measure density-functional theory (FM-DFT). FM-DFT is a powerful approach to studying the structure and the phase behavior of nanoconfined fluids. We report the computational procedure and the calculated data for nanoslits with different widths and for a wide range of hard-sphere fluid densities. The high accuracy of the resulting density profiles and optimum grid-size values in numerical integration are verified. The data reveal a number of interesting features of hard spheres in nanoslits, which are different from the bulk hard-sphere systems. These data are also useful for a variety of purposes, including obtaining the shear stress, thermal conductivity, adsorption, solvation forces, free volume and prediction of phase transitions.

Sleeping sickness (causal agent, Trypanosoma sp. parasite) causes huge morbidity and mortality in Africa (both human and livestock) in particular and zoo animals worldwide. Three of the four currently approved drugs (Pentamidine, Melarsoprol, Eflornithine, and Nifurtimox) were developed over 50 years ago. Current therapies are unsatisfactory due to unacceptable level of side effects. Pentamidine, an aromatic diamidine, safest so far, inhibits mitochondrial enzymes. Furthermore, it is effective only in early stages of infections and not on the later stage. Melarsoprol, practically insoluble in water, is very toxic and it is given intravenously (i.v.) for later stage infections only. Other drugs like eflornithine and nitfurtimox are also unsatisfactory for various reasons. Human serum derived high-density lipoprotein (HDL; not mouse or any other mammalian HDL) shows trypanolytic effect in vitro and in vivo on T. brucei. But the mechanism of action of human HDL is far from clear. In the absence of novel drug leads, nanodrugs might be valid options as nanoparticles show better accessibility to cells, supramolecular interactions due to enormous increase in surface area to volume ratio, altered partition coefficient, etc. Surface-modified hydrophobic microsilica (FS), mixture of micro- and nanosilica (Dsethvasan) and nanosilica (AL) were characterized by UV–Vis, DLS, SEM, EDAX, AFM, and XRD. Trypanosoma evansi collected from infected horses were injected in mice. Control infected mouse (n = 30) showed 100% mortality within 72±24 h of injection. Dsethvasan-treated mice (n = 30) survived for 192±24 h. FS-treated mice (n = 30) survived for 120±24 h but the AL-treated mice (n = 30) died within 72±24 h of inoculation like infected control. Hydrophobic Dsethvasan which consists of pure amorphous forms of micro- and nanosilica works better than FS (AL is not at all effective). Therefore, micro- and nanomixture of amorphous silica is best suited for treating Trypanosoma infection in mice. The possible role of ratio of higher to lower size class has been discussed.