32 research outputs found
South African Literary Cartographies: A Post-Transitional Palimpsest
This article investigates three South African novels in an attempt to mapthe movement between transitional cultural production andpost-transitional literature of the present. I briefly outline PhaswaneMpe’s Welcome to our Hillbrow (2001) as a formative text of the SouthAfrican transitional period before discussing Kgebetli Moele’s Room 207(2006) and Ceridwen Dovey’s Blood Kin (2007) as post-transitional texts.These novels all circle around issues of place and space, while alsorevealing the shifts in South African cultural history, as they comprise aset of related perspectives that inscribe meaning across times and spaces.I argue that a palimpsestic reading of this fiction opens up thepossibility of reconceptualizing the relationship between space, place,and transnational connectivity. Each of the three texts under discussionwrites the space of the city as a type of situated transnationalism wherethe local and the global exist as coeval discourses of signification. Thefecundity of a palimpsestic reading lies in the revelation of how onetransitional experience is already present in another. By inscribing onediscursive act over another, the ruptures and continuities betweentextualizations reveal a wealth of imaginaries that, I argue, define theidea of post-transitional South African literature. But perhaps mostimportantly, the post-transitional can be read as a palimpsestic conceptitself, much like the fiction explored in this article, in that it enablesa reading of the new in a way in which the layers of the past are stillreflected through it. Rather than moving in a temporal linear fashion,post-transitional literature creates a palimpsest in which we can read theimaginaries circulating through and shaping South African culturalformations today
Defect-Free Carbon Nanotube Coils
Carbon nanotubes are promising building blocks for various nanoelectronic
components. A highly desirable geometry for such applications is a coil.
However, coiled nanotube structures reported so far were inherently defective
or had no free ends accessible for contacting. Here we demonstrate the
spontaneous self-coiling of single-wall carbon nanotubes into defect-free coils
of up to more than 70 turns with identical diameter and chirality, and free
ends. We characterize the structure, formation mechanism, and electrical
properties of these coils by different microscopies, molecular dynamics
simulations, Raman spectroscopy, and electrical and magnetic measurements. The
coils are highly conductive, as expected for defect-free carbon nanotubes, but
adjacent nanotube segments in the coil are more highly coupled than in regular
bundles of single-wall carbon nanotubes, owing to their perfect crystal
momentum matching, which enables tunneling between the turns. Although this
behavior does not yet enable the performance of these nanotube coils as
inductive devices, it does point a clear path for their realization. Hence,
this study represents a major step toward the production of many different
nanotube coil devices, including inductors, electromagnets, transformers, and
dynamos
Inhibiting α-Synuclein Oligomerization by Stable Cell-Penetrating β-Synuclein Fragments Recovers Phenotype of Parkinson's Disease Model Flies
The intracellular oligomerization of α-synuclein is associated with Parkinson's disease and appears to be an important target for disease-modifying treatment. Yet, to date, there is no specific inhibitor for this aggregation process. Using unbiased systematic peptide array analysis, we indentified molecular interaction domains within the β-synuclein polypeptide that specifically binds α-synuclein. Adding such peptide fragments to α-synuclein significantly reduced both amyloid fibrils and soluble oligomer formation in vitro. A retro-inverso analogue of the best peptide inhibitor was designed to develop the identified molecular recognition module into a drug candidate. While this peptide shows indistinguishable activity as compared to the native peptide, it is stable in mouse serum and penetrates α-synuclein over-expressing cells. The interaction interface between the D-amino acid peptide and α-synuclein was mapped by Nuclear Magnetic Resonance spectroscopy. Finally, administering the retro-inverso peptide to a Drosophila model expressing mutant A53T α-synuclein in the nervous system, resulted in a significant recovery of the behavioral abnormalities of the treated flies and in a significant reduction in α-synuclein accumulation in the brains of the flies. The engineered retro-inverso peptide can serve as a lead for developing a novel class of therapeutic agents to treat Parkinson's disease
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"On the fringe of dreamtime...": South African Indian literature, race and the boundaries of scholarship
My dissertation addresses a lacuna of contemporary scholarship by utilizing South African Indian literature as a lens through which to view South African culture in a different light. Drawing on South African Indian writings emerging post-1976, I explore this fiction as a cultural history that investigates how race is negotiated in Apartheid and post-Apartheid South Africa. I have found that the seemingly marginal construction of South African Indian identity is central to understanding the ideological underpinnings of South African culture as it destabilizes rigid constructions of race. In part because of its location outside of the dominant black/white taxonomy in South Africa, this literature problematizes bounded notions of race by undermining culturally constructed oppositions that establish difference and sameness. Ideas of "Indianness" are therefore crucial to understanding cultural and institutional relations in South Africa more broadly as they reveal how race, power and politics operate outside of dominant racial oppositions, thereby repositioning the terms of the debates. Narrative in post-Apartheid South Africa forms a dialogue with both the silences of Apartheid and those of the Truth and Reconciliation Commission. My work therefore investigates how literary texts undermine culturally constructed oppositions that establish difference and sameness, in dialogue with the re-textualizing processes of the TRC. I concentrate on contemporary South African Indian fiction of the last twenty-five years, including Achmat Dangor's Kafka's Curse (1997) and Bitter Fruit (2001), Farida Karodia's Other Secrets (2000), Beverley Naidoo's Out of Bounds (2001), Agnus Sam's Jesus is Indian and Other Stories (1989), Jayapraga Reddy's On the Fringe of Dreamtime and Other Stories (1987), Imraan Coovadia's The Wedding (2001) and Shamin Sarif's The World Unseen (2001)
The Herpes Simplex Virus Type 1 vhs-UL41 Gene Secures Viral Replication by Temporarily Evading Apoptotic Cellular Response to Infection: Vhs-UL41 Activity Might Require Interactions with Elements of Cellular mRNA Degradation Machinery
We have previously shown that herpes simplex virus type 1 (HSV-1) infection is associated with early destabilization/degradation of infected cell mRNAs and consequent shutoff of host protein synthesis by the activity of the virion-associated host shutoff (vhs) UL41 protein. Wild-type (wt) virus destabilized/degraded the housekeeping β-actin and α-tubulin mRNAs as well host stress functions, like the heat shock 70 protein induced postinfection. vhs mutants did not degrade the mRNAs. Elaborate studies by others have been concerned with the mode of mRNA degradation and the mRNAs affected. We now describe vhs activity in primary cultures of mouse cerebellar granule neurons (CGNs). Specifically, (i) upon infection in the presence of actinomycin D to test activity of input viral particles, there was a generalized inhibition of protein synthesis, which depended on the input multiplicity of infection (MOI). (ii) Low-MOI infection with vhs-1 mutant virus was associated with increased synthesis of all apparent proteins. Higher MOIs caused some shutoff, albeit significantly lower than that of wt virus. This pattern could reflect an interaction(s) of vhs-1 protein with host machinery involved in cellular mRNA destabilization/degradation, sequestering this activity. (iii) wt virus infection was associated with cell survival, at least for a while, whereas mutant virus induced apoptotic cell death at earlier times. (iv) wt virus replicated well in the CGNs, whereas there was no apparent replication of the vhs-1 mutant virus. (v) The vhs-1 mutant could serve as helper virus for composite amplicon vectors carrying marker genes and the human p53 gene. Ongoing studies test the use of vhs-1-based composite oncolytic vectors towards cancer gene therapy
Cosmopolitanism and the unfollowable routines and rituals in Ishtiyaq Shukri’s The Silent Minaret:
This article explores how Ishtiyaq Shukri’s The Silent Minaret critiques the limited and severely uneven forms of hospitality that characterise post-9/11 Britain. It also examines how the text gestures towards the possibility of a non-violent, inclusive cosmopolitanism. The piece begins by relating recent debates surrounding the “War on Terror”, as well as Britain’s decision to leave the European Union to the novel’s major concerns. It then turns to the novel, and summarises incidents in which the principal character, Issa Shamshuddin, is traumatised and harmed by the Islamophobia and anti-immigration policies evident in the London portrayed in the text. Next, it turns to an analysis of the strange and irreproducible rituals of Issa’s neighbour, Frances. The article concludes that that these unfollowable rituals posit how a truly cosmopolitan society would function
A Novel, Sensitive Assay for Behavioral Defects in Parkinson's Disease Model Drosophila
Parkinson's disease is a common neurodegenerative disorder with the pathology of α-synuclein aggregation in Lewy bodies. Currently, there is no available therapy that arrests the progression of the disease. Therefore, the need of animal models to follow α-synuclein aggregation is crucial. Drosophila melanogaster has been researched extensively as a good genetic model for the disease, with a cognitive phenotype of defective climbing ability. The assay for climbing ability has been demonstrated as an effective tool for screening new therapeutic agents for Parkinson's disease. However, due to the assay's many limitations, there is a clear need to develop a better behavioral test. Courtship, a stereotyped, ritualized behavior of Drosophila, involves complex motor and sensory functions in both sexes, which are controlled by large number of neurons; hence, behavior observed during courtship should be sensitive to disease processes in the nervous system. We used a series of traits commonly observed in courtship and an additional behavioral trait—nonsexual encounters—and analyzed them using a data mining tool. We found defective behavior of the Parkinson's model male flies that were tested with virgin females, visible at a much younger age than the climbing defects. We conclude that this is an improved behavioral assay for Parkinson's model flies