Politicized and depoliticized ethnicities,power relations and temporality: insights to outsider research from comparative and transnational fieldwork

The insider and outsider positions in migration studies have conventionally been approached in terms of ethnic or national belonging. Recently scholars have problematized the essentialist approaches to these roles by arguing for the inclusion of multiple intersecting social locations that are at play in the constitution of researcher positionality. Less attention has been paid, however, on how different ethnicities are constructed and how they can become politicized and depoliticized at particular moments during the research process. This article discusses the fieldwork experiences of two “apparent outsiders” to the studied diaspora community. Drawing from our experiences in multi-sited and comparative fieldwork on the Kurdish diaspora, we argue that rather than taking insider and outsider positions as a starting-point to understand researcher positionality, scholars need to look at particular moments of insiderness and outsiderness to grasp how the researcher’s assumed ethnicity becomes politicized and depoliticized during ethnographic fieldwork.     

Vibrational Dynamics of Icosahedrally Symmetric Biomolecular Assemblies Compared with Predictions Based on Continuum Elasticity

Coarse-grained elastic network models elucidate the fluctuation dynamics of proteins around their native conformations. Low-frequency collective motions derived by simplified normal mode analysis are usually involved in biological function, and these motions often possess noteworthy symmetries related to the overall shape of the molecule. Here, insights into these motions and their frequencies are sought by considering continuum models with appropriate symmetry and boundary conditions to approximately represent the true atomistic molecular structure. We solve the elastic wave equations analytically for the case of spherical symmetry, yielding a symmetry-based classification of molecular motions together with explicit predictions for their vibrational frequencies. We address the case of icosahedral symmetry as a perturbation to the spherical case. Applications to lumazine synthase, satellite tobacco mosaic virus, and brome mosaic virus show that the spherical elastic model efficiently provides insights on collective motions that are otherwise obtained by detailed elastic network models. A major utility of the continuum models is the possibility of estimating macroscopic material properties such as the Young's modulus or Poisson's ratio for different types of viruses.     

HIV‐1 infection of CD4 T cells impairs antigen‐specific B cell function

Failures to produce neutralizing antibodies upon HIV‐1 infection result in part from B‐cell dysfunction due to unspecific B‐cell activation. How HIV‐1 affects antigen‐specific B‐cell functions remains elusive. Using an adoptive transfer mouse model and ex vivo HIV infection of human tonsil tissue, we found that expression of the HIV‐1 pathogenesis factor NEF in CD4 T cells undermines their helper function and impairs cognate B‐cell functions including mounting of efficient specific IgG responses. NEF interfered with T cell help via a specific protein interaction motif that prevents polarized cytokine secretion at the T‐cell–B‐cell immune synapse. This interference reduced B‐cell activation and proliferation and thus disrupted germinal center formation and affinity maturation. These results identify NEF as a key component for HIV‐mediated dysfunction of antigen‐specific B cells. Therapeutic targeting of the identified molecular surface in NEF will facilitate host control of HIV infection.