Comparative genomics of Steinernema reveals deeply conserved gene regulatory networks

Background: Parasitism is a major ecological niche for a variety of nematodes. Multiple nematode lineages have specialized as pathogens, including deadly parasites of insects that are used in biological control. We have sequenced and analyzed the draft genomes and transcriptomes of the entomopathogenic nematode Steinernema carpocapsae and four congeners (S. scapterisci, S. monticolum, S. feltiae, and S. glaseri). Results: We used these genomes to establish phylogenetic relationships, explore gene conservation across species, and identify genes uniquely expanded in insect parasites. Protein domain analysis in Steinernema revealed a striking expansion of numerous putative parasitism genes, including certain protease and protease inhibitor families, as well as fatty acid- and retinol-binding proteins. Stage-specific gene expression of some of these expanded families further supports the notion that they are involved in insect parasitism by Steinernema. We show that sets of novel conserved non-coding regulatory motifs are associated with orthologous genes in Steinernema and Caenorhabditis. Conclusions: We have identified a set of expanded gene families that are likely to be involved in parasitism. We have also identified a set of non-coding motifs associated with groups of orthologous genes in Steinernema and Caenorhabditis involved in neurogenesis and embryonic development that are likely part of conserved protein–DNA relationships shared between these two genera

Time to Switch to Second-line Antiretroviral Therapy in Children With Human Immunodeficiency Virus in Europe and Thailand.

Background: Data on durability of first-line antiretroviral therapy (ART) in children with human immunodeficiency virus (HIV) are limited. We assessed time to switch to second-line therapy in 16 European countries and Thailand. Methods: Children aged <18 years initiating combination ART (≥2 nucleoside reverse transcriptase inhibitors [NRTIs] plus nonnucleoside reverse transcriptase inhibitor [NNRTI] or boosted protease inhibitor [PI]) were included. Switch to second-line was defined as (i) change across drug class (PI to NNRTI or vice versa) or within PI class plus change of ≥1 NRTI; (ii) change from single to dual PI; or (iii) addition of a new drug class. Cumulative incidence of switch was calculated with death and loss to follow-up as competing risks. Results: Of 3668 children included, median age at ART initiation was 6.1 (interquartile range (IQR), 1.7-10.5) years. Initial regimens were 32% PI based, 34% nevirapine (NVP) based, and 33% efavirenz based. Median duration of follow-up was 5.4 (IQR, 2.9-8.3) years. Cumulative incidence of switch at 5 years was 21% (95% confidence interval, 20%-23%), with significant regional variations. Median time to switch was 30 (IQR, 16-58) months; two-thirds of switches were related to treatment failure. In multivariable analysis, older age, severe immunosuppression and higher viral load (VL) at ART start, and NVP-based initial regimens were associated with increased risk of switch. Conclusions: One in 5 children switched to a second-line regimen by 5 years of ART, with two-thirds failure related. Advanced HIV, older age, and NVP-based regimens were associated with increased risk of switch

Mexican Photography Collected: Graciela Iturbide and Tina Modotti

The act of collecting has increasingly become a focus of art historians in the last thirty years. Susan Pearce, Mieke Bal, Bruce Althuser and other scholars have written theoretical perspectives illuminating the ways in which the collecting of art influences the identity of a particular collector and in turn the ways in which the process of collecting art itself attaches meanings to objects. In the last twenty years, there has been a surge in the collecting of Mexican photography dating from the 1920s to the contemporary period. Mexican photography has a long history of being at once an art form and documentation meant to bring social change to the people of Mexico. Tina Modotti was among the first to create photographs of this type in Mexico beginning in the 1920s. Graciela Iturbide is a contemporary photographer who continues to work in a similar manner. This thesis examines specific collections of photographs taken in Mexico. Daniel Greenberg and Susan Steinhauser, a Los Angeles couple collects many art objects including Graciela Iturbide photographs. Susie Tompkins Buell, a social activist living in San Francisco also collects objects of art including Tina Modotti photographs. Greenberg, Steinhauser, and Buell use their collections to underscore their own Identities as socially conscious people. The collectors’ identities have come to enhance and perhaps supplant the original meanings gleaned from the objects they collect

Epistemic Communities: Description and Hierarchic Categorization

Understanding the structure of knowledge communities, and particularly the organization of “epistemic communities”, or groups of agents sharing common knowledge concerns, is usually based on either social relationships or semantic similarity. To link social and semantic aspects, a formal framework based on Galois lattices (or concept lattices) categorizes epistemic communities in an automated and hierarchically structured way. The process rebuilds a whole community structure and taxonomy, and notably fields and subfields gathering a certain proportion of agents. It is applied to empirical data to exhibit these alleged structural properties, successfully compared with categories given by domain experts.social complex systems, community representation and categorization, scientometrics, applied epistemology, knowledge discovery in databases,