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We report a simple yet robust and reproducible technique to create surface patterns with submicrometer scale resolution on polymer films coated on nonplanar and curved surfaces at room temperature, without applying any external pressure. The imprinting is achieved by using a flexible, patterned polyvinyl alcohol (PVA) stamp in a controlled solvent vapor atmosphere, where the patterned foil comes in adhesive contact with a swollen and softened polymer film. The stamp bends along the contours of the curved surface to make a complete contact with a soft and swollen viscoelastic polymer film to make an imprint. The soft surface of the film then deforms on the length scale of each structure on the stamp to make a conformal contact, forming a negative replica of the stamp pattern on the film surface. The flexible PVA stamp is later dissolved in water after the patterning process is complete. It is shown that the technique is portable across a variety of polymer coatings, substrates, and geometries. Further, we also show that the same technique can be employed to create complex 2-D microstructures on nonplanar surfaces by multiple imprintings. [ABSTRACT FROM AUTHOR]

We study the non-spherical gravitational collapse of the strange quark null fluid. The interesting feature which emerges is that the non-spherical collapse of charged strange quark matter leads to a naked singularity whereas the gravitational collapse of neutral quark matter proceeds to form a black hole. We extend the earlier work of Harko and Cheng [Phys. Lett. A 266 (2000) 249] to the non-spherical case. [ABSTRACT FROM AUTHOR]

Background: Despite enhanced recovery programmes, length of stay is variable following robotic assisted radical cystectomy (RARC). The aim of this study was to assess the impact socioeconomic deprivation on recovery following RARC. Methods: The prospectively maintained RARC databases at two tertiary referral hospitals were reviewed from 2015 to 2017. Demographic, histological, and outcome data including length of stay (LOS), operation time and blood loss were recorded. The Index of Multiple Deprivation, was chosen as a deprivation index as this is used by the UK government to direct funding and resources to regions, towns and postal codes by assessing a number of indicators. Results: During the study period, 340 consecutive patients underwent RARC. Deprivation deciles were significantly higher in site 1 patients (7.9 in site 1 vs 6.6 in site 2, p < 0.001) implying that these patients are more likely to have higher incomes, levels of education and improved living environments. The mean operating time was longer in the site 1 cohort (397 vs 366 min, p > 0.001) with a reduced mean blood loss volume (252 and 484 mL, p < 0.001). There was a significant difference in mean LOS (6.2 days in site 1 vs 10.6 days in site 2, p < 0.001). On multivariable analysis, a higher deprivation decile did not predict LOS (OR = 1, 95% CI = 0.9–1.1, p = 0.407). Sex and operation site were however significantly associated with LOS (p = 0.006 and <0.001). Conclusion: Recovery following RARC was independent of socioeconomic status when comparing two hospitals with diverse catchment areas in the UK. [ABSTRACT FROM AUTHOR]

Abstract  Surface-capped CdSe and CdTe nano-crystals (NCs) have been synthesized using cadmium acetate, oleic acid and respective tri-octylphosphine chalcogenide (TOPE; E = Se/Te) in diphenyl ether (DPE). Well-dispersed CdSe particles showed two absorption bands at the region of 431–34 and 458–60 nm in optical absorption study. A band-edge emission resulted at 515 nm with an excitation energy of 400 nm, in its photoluminescence (PL) spectrum. Similarly, UV–visible absorption study of CdTe revealed an absorption band at [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs) are crystalline materials with ultrahigh porosity and tunable physico-chemical properties. But most MOFs are electrical insulators which restricts their use in electronic devices. In the present study, a field effect transistor (FET) based on a proton-conductive MOF was investigated. Imidazole was used as a proton conductor to increase the conductivity of the copper benzene tricarboxylate (CuBTC) MOF and, further, it was used to develop the FET. The CuBTC was synthesized using the traditional solvothermal method. The proton-conductive MOF was synthesized by post-modification of the CuBTC via the pore filling method using imidazole molecules, which achieved a proton conductivity of ~1.04  ×  10−4 S cm−1 at 70 °C (anhydrous conditions). The proton conductive MOF was characterized by various techniques; spectroscopically by Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, x-ray absorption spectroscopy, energy dispersive spectroscopy, alternating current (a.c.) impedance spectroscopy; thermally using thermogravimetric analysis; structurally using powder x-ray diffraction; morphologically using field emission scanning electron microscopy; electrically by FETs. [ABSTRACT FROM AUTHOR]

Objective: The study was undertaken to evaluate the antioxidant activity of fruits of Trichosanthes dioica (Cucurbitaceae) and compared with ascorbic acid (Standard). Materials and Methods: Anti-oxidant activity of aqueous extract of Trichosanthes dioica (TSD) fruits was studied for its free radical scavenging property in different in vitro methods as 1, 1 diphenyl-2- picryl hydrazyl, nitric oxide, reducing power assay and hydrogen peroxide radical method. Different concentrations of aqueous extract of TSD were prepared and evaluated by standard methods. Results: The IC50 values of aqueous extract of TSD were compared with ascorbic acid (Standard) and it was noted that, the extract showed significant concentration dependent free radical scavenging property in all the methods. Conclusion: Results from the study showed that aqueous extract of TSD possess in vitro free radical scavenging activity. The findings could justify the inclusion of this plant in the management of antioxidant activity. [ABSTRACT FROM AUTHOR]

Abstract??Osmotic coefficient data have been obtained for the binary aqueous solutions of alkaline-earth chlorides (MgCl2, CaCl2and BaCl2) at 298.15 K using a vapor pressure osmometer. The measurements are extended to aqueous ternary solutions (containing a fixed concentration of 0.1 mol?kg?118-Crown-6 (18C6) having various electrolyte concentrations (0.01?0.2 mol?kg?1). The mean activity coefficients of the ions and of 18C6 in binary and ternary solutions were obtained through calculations of activity and osmotic coefficient data. The lowering of activity coefficients of the ions and of 18C6 in ternary solutions is attributed to the presence of host-guest type equilibria due to complexation between them in the case of solutions containing Ca2+and Ba2+ions. The data are further subjected to scrutiny by applying the methodology developed by Patil and Dagade based on the McMillan-Mayer theory of solutions to obtain thermodynamic equilibrium constant values through transfer Gibbs energies. It is noted that the size of the crown cavity (diameter 0.266?0.32 nm), charge density of ions (i.e., coulombic interactions) as well as hydrophobic interaction play a major role in governing the occurrence and stability of the complexed species. The results are compared with those reported earlier for alkali-halides and 18C6 complexes and discussed further from the point of view of the importance of ion-pair formation equilibria in aqueous solutions. [ABSTRACT FROM AUTHOR]

This paper reports a systematic search of X-ray cavities, density jumps, and shocks in the intergalactic environment of the galaxy group IC 1262 using Chandra, GMRT, and Very Large Array archival observations. The X-ray imaging analysis reveals a pair of X-ray cavities to the north and south of the X-ray peak, at projected distances of 6.48 kpc and 6.30 kpc respectively. Total mechanical power contained in both of these cavities is found to be ∼12.37 × 1042 erg s−1, and compares well with the X-ray luminosity, within the cooling radius, measured to be ∼3.29 × 1042 erg s−1, suggesting that the mechanical power injected by the central AGN efficiently balances the radiative loss. We detect a previously unknown X-ray cavity at the position of the southern radio lobe in the intra-group medium and find a loop of excess X-ray emission extending ∼100 kpc southwest from the central galaxy. The X-ray cavity at the position of the southern radio lobe probably represents a first generation X-ray cavity. Two surface brightness edges are evident to the west and northeast of the center of this group. The radio galaxy at the core of the IC 1262 group is a rare low-redshift ultra-steep radio galaxy, its spectral index being α ∼ −1.73 (including the central AGN) and α ∼ −2.08 (excluding the central AGN). We detect a radio phoenix embedded within the southern radio lobe, for the first time in a poor group, with a spectral index (α ≤ −1.92). The spectral index distribution across the phoenix steepens with increasing distance from its intensity peak. [ABSTRACT FROM AUTHOR]