Roman Studios

The Roman residencies of two American artists, nineteenth-century sculptor Edmonia Lewis and contemporary photographer Carrie Mae Weems, illustrate the value of locating classical receptions in the African diaspora in unexpected places and mediums. Rome’s status as the epicenter of ancient imperialism, as well as a hub for the intertwined legacies of race and neoclassicism in transatlantic modernity, makes it a particularly charged site for black women artists. Analyzing photographs in Weems’s 2006 series Roaming as portals into the cultural and geographic spaces occupied by Lewis as she designed her 1876 sculpture Death of Cleopatra, this chapter demonstrates the breadth and vibrancy of black women’s visual interventions into modern perceptions of the classical past. Inspired by the enduring material and cultural presences of ancient Egypt in modern Rome, both artists mark out Roman spaces as historic as well as contemporary spaces for blackness, rather than facades performing whiteness.

Tasting Space: Sights of the Commune in Henry James’s Paris

This chapter moves from sights of Paris as a revolutionary underground to sites of Paris in ruin, from unexpected forms of imperial adventure or subterranean possibility to uncanny forms of affective possession. While The American Scene has been the privileged site to examine Henry James’s fascination with—and affective responses to—lost landmarks and newly minted ruins, I excavate the sights of and detours around the post-Commune ruins of Paris in his writings and contemporary periodical culture. Situating James’s attention to charred landscape and vanished tourist sights alongside their ongoing returns in U.S. print and visual culture, I suggest, crucially reconfigures James’s transformative and uncannily embodied “historic sense” even as it recovers the post-Commune ruinscape that came to function as an unexpectedly charged site of transnational memory in U.S. literary, visual and performance culture.

Modeling and Simulation studies for Aluminium - Fluoride Interactions in Nalgonda Defluoridation Process

A model simulator NALD-2 has been developed to study the interactions of fluoride and aluminium in the Nalgonda Defluoridation Process, which principally involves the preferential adsorption of fluoride ions onto insoluble aluminium hydroxides that are formed from alum hydrolysis reactions and undergo precipitation. This model represents the defluoridation mechanism taking into account the charged behavior of the amphoteric aluminium hydroxide colloids, charged site densities, and fluoride complexation reactions in order to predict the extent of defluoridation and concentrations of dissolved and colloidal aluminium in the treated water as functions of pH, alum dosage and raw fluoride concentrations. Model validations were carried out using secondary data of Selvapathy & Arjunan (1995) for total residual aluminium in Nalgonda treated water. Slight variations in pH into the acidic range cause substantial increase in colloidal aluminium and hence pH and alum dosages are important control parameters to limit residual aluminium in treated water. The NALD-2 simulator helps in predicting optimum alum dosages for minimum residual aluminium in the treated water. It was concluded that the dosages of alum recommended in the Nalgonda method cannot bring down the residual Al below the permissible limit of 0.2mg/L in the treated water.

Molecular Basis for Cation Selectivity in Claudin-2–based Paracellular Pores: Identification of an Electrostatic Interaction Site

Paracellular ion transport in epithelia is mediated by pores formed by members of the claudin family. The degree of selectivity and the molecular mechanism of ion permeation through claudin pores are poorly understood. By expressing a high-conductance claudin isoform, claudin-2, in high-resistance Madin-Darby canine kidney cells under the control of an inducible promoter, we were able to quantitate claudin pore permeability. Claudin-2 pores were found to be narrow, fluid filled, and cation selective. Charge selectivity was mediated by the electrostatic interaction of partially dehydrated permeating cations with a negatively charged site within the pore that is formed by the side chain carboxyl group of aspartate-65. Thus, paracellular pores use intrapore electrostatic binding sites to achieve a high conductance with a high degree of charge selectivity.

Selectivity of cations and nonelectrolytes for acetylcholine-activated channels in cultured muscle cells.

The selectivity of acetylcholine (A-Ch)-activated channels for alkali cations, organic cations, and nonelectrolytes in cultured muscle cells has been studied. To test the effect of size, charge, and hydrogen-binding capacity of permeant molecules on their permeability, we have obtained the selectivity sequences of alkali cations, compared the permeability of pairs of permeant molecules with similar size and shape but differing in charge, and studied the permeability of amines of different hydrogen bonding capacity. ACh-activated channels transport alkali cations of small hydration radii and high mobility. The molecules with positive charge and (or) a hydrogen-bond donating moiety are more permeable than the ones without. On the other hand, several nonelectrolytes, i.e., ethylene glycol, formamide, and urea, do have a small, but measurable, permeability through the channels. These results are consistent with a model that ACh-activated channel is a water-filled pore containing dipoles or hydrogen bond accepting groups and a negative charged site with a pK of 4.8.