Evidence for topological nonequilibrium in magnetic configurations

We use direct numerical simulations to study the evolution, or relaxation, of magnetic configurations to an equilibrium state. We use the full single-fluid equations of motion for a magnetized, non-resistive, but viscous fluid; and a Lagrangian approach is used to obtain exact solutions for the magnetic field. As a result, the topology of the magnetic field remains unchanged, which makes it possible to study the case of topological nonequilibrium. We find two cases for which such nonequilibrium appears, indicating that these configurations may develop singular current sheets.Comment: 10 pages, 5 figure

Velocity-force characteristics of an interface driven through a periodic potential

We study the creep dynamics of a two-dimensional interface driven through a periodic potential using dynamical renormalization group methods. We find that the nature of weak-drive transport depends qualitatively on whether the temperature $T$ is above or below the equilibrium roughening transition temperature $T_c$. Above $T_c$, the velocity-force characteristics is Ohmic, with linear mobility exhibiting a jump discontinuity across the transition. For $T \le T_c$, the transport is highly nonlinear, exhibiting an interesting crossover in temperature and weak external force $F$. For intermediate drive, $F>F_*$, we find near $T_c^{-}$ a power-law velocity-force characteristics $v(F)\sim F^\sigma$, with $\sigma-1\propto \tilde{t}$, and well-below $T_c$, $v(F)\sim e^{-(F_*/F)^{2\tilde{t}}}$, with $\tilde{t}=(1-T/T_c)$. In the limit of vanishing drive ($F\ll F_*$) the velocity-force characteristics crosses over to $v(F)\sim e^{-(F_0/F)}$, and is controlled by soliton nucleation.Comment: 18 pages, submitted to Phys. Rev.

Investigation of the role of the thiazolidinedione ring of troglitazone in inducing hepatotoxicity

10.1016/j.toxlet.2009.10.014Toxicology Letters1922141-149TOLE

Direct toxicity effects of sulfo-conjugated troglitazone on human hepatocytes

10.1016/j.toxlet.2010.03.010Toxicology Letters1952-3135-141TOLE

Multiple precarity and intimate family life among African-Chinese families in Guangzhou

Formal ties between China and several African states have intensified in recent years. Alongside growing economic and trade cooperation, the international mobility of people between China and African states is increasing. Recent studies have shown that African migrants face institutional barriers to integration in Chinese society, however, and the personal and social consequences of these barriers remain under-researched, especially the dynamics of intimate family life. Drawing upon concepts of precarity and 'low-end globalisation', this study examines how African-Chinese families navigate everyday life, including work, family and children's education. It is based on ethnographic fieldwork comprising observations and in-depth interviews with African-Chinese families and one community leader (n = 19). These reveal how families confront the pervasiveness of legal, economic and social precarization in multiple overlapping domains. These social forces have intergenerational repercussions, with adverse impacts on family life, interpersonal relationships and sense of belonging to the local community. Yet precarity offers conditions for practices of empowerment. We conclude with implications for migration studies

Multiple precarity and intimate family life among African-Chinese families in Guangzhou

Formal ties between China and several African states have intensified in recent years. Alongside growing economic and trade cooperation, the international mobility of people between China and African states is increasing. Recent studies have shown that African migrants face institutional barriers to integration in Chinese society, however, and the personal and social consequences of these barriers remain under-researched, especially the dynamics of intimate family life. Drawing upon concepts of precarity and 'low-end globalisation', this study examines how African-Chinese families navigate everyday life, including work, family and children's education. It is based on ethnographic fieldwork comprising observations and in-depth interviews with African-Chinese families and one community leader (n = 19). These reveal how families confront the pervasiveness of legal, economic and social precarization in multiple overlapping domains. These social forces have intergenerational repercussions, with adverse impacts on family life, interpersonal relationships and sense of belonging to the local community. Yet precarity offers conditions for practices of empowerment. We conclude with implications for migration studies