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Proper functioning of the nervous system relies not only on the generation of a vast repertoire of distinct neural cell types but also on the precise neural circuitry within them. How the generation of highly diverse neural populations is regulated during development remains a topic of interest. Landmark studies in Drosophila have identified the genetic and temporal cues regulating neural diversity and thus have provided valuable insights into our understanding of temporal patterning of the central nervous system. The development of the Drosophila central complex, which is mostly derived from type II neural stem cell (NSC) lineages, showcases how a small pool of NSCs can give rise to vast and distinct progeny. Similar to the human outer subventricular zone (OSVZ) neural progenitors, type II NSCs generate intermediate neural progenitors (INPs) to expand and diversify lineages that populate higher brain centers. Each type II NSC has a distinct spatial identity and timely regulated expression of many transcription factors and mRNA binding proteins. Additionally, INPs derived from them show differential expression of genes depending on their birth order. Together type II NSCs and INPs display a combinatorial temporal patterning that expands neural diversity of the central brain lineages. We cover advances in current understanding of type II NSC temporal patterning and discuss similarities and differences in temporal patterning mechanisms of various NSCs with a focus on how cell-intrinsic and extrinsic hormonal cues regulate temporal transitions in NSCs during larval development. Cell extrinsic ligands activate conserved signaling pathways and extrinsic hormonal cues act as a temporal switch that regulate temporal progression of the NSCs. We conclude by elaborating on how a progenitor's temporal code regulates the fate specification and identity of distinct neural types. At the end, we also discuss open questions in linking developmental cues to neural identity, circuits, and underlying behaviors in the adult fly.

This article describes a class project designed to develop students’ abilities to use their sociological imagination to better understand the structural sources of racial inequality. The event consisted of a memorial reading of the names of more than 4,000 documented lynch victims in the United States. Authors conducted a pretest and posttest on racial attitudes in large Introduction to Sociology courses. Posttest responses evidenced less support for “colorblind” ideologies and greater support for structural sources of inequality.

An evaluation showed the incenerator to be capable of reducing these materials to a fine ash. The waste/fuel ratio averaged 1.49 lb of human waste/lb of fuel, 1.47 lb of garbage/lb. of fuel, and 0.37 lbof rubbish/lb of fuel. Of the total fuel consumption, 22% was used to destroy odors, and 78% was used for incineration. The efficiency of the incinerator was reduced when using combustible materials because of the inadequate supply of air to the combustion chamber. The incinerator was not recommended for use in the field.