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Murine models are often used to study the pathogenicity and dissemination of the enteric pathogen Salmonella enterica serovar Typhimurium. Here, we quantified S. Typhimurium population dynamics in mice using the STAMPR analytic pipeline and a highly diverse S. Typhimurium barcoded library containing ~55,000 unique strains distinguishable by genomic barcodes by enumerating S. Typhimurium founding populations and deciphering routes of spread in mice. We found that a severe bottleneck allowed only one in a million cells from an oral inoculum to establish a niche in the intestine. Furthermore, we observed compartmentalization of pathogen populations throughout the intestine, with few barcodes shared between intestinal segments and feces. This severe bottleneck widened and compartmentalization was reduced after streptomycin treatment, suggesting the microbiota plays a key role in restricting the pathogen's colonization and movement within the intestine. Additionally, there was minimal sharing between the intestine and extraintestinal organ populations, indicating dissemination to extraintestinal sites occurs rapidly, before substantial pathogen expansion in the intestine. Bypassing the intestinal bottleneck by inoculating mice via intravenous or intraperitoneal injection revealed that Salmonella re-enters the intestine after establishing niches in extraintestinal sites by at least two distinct pathways. One pathway results in a diverse intestinal population. The other re-seeding pathway is through the bile, where the pathogen is often clonal, leading to clonal intestinal populations and correlates with gallbladder pathology. Together, these findings deepen our understanding of Salmonella population dynamics. [ABSTRACT FROM AUTHOR]

This article uses campaign reports and memoir literature to explore tsarist officers' views of masculinity—both their own and that of their opponents—during the conquest of the Caucasus, focusing particularly on the Nicolaevan era. It frames conquest as a form of cultural exchange and argues that tsarist officers' understandings of the gender order of both their own and combatant societies were a critical component of this cultural exchange. In particular, stereotypically feminine traits like mercy and gentleness were important to the cultural script of conquest in the Caucasus. To offer mercy implied the right to punish, a right which had to constantly be reasserted; the assertion of authority was deeply gendered and necessitated the subordination of local men. A case study of ritual humiliation during the conquest of the Caucasus illustrates how this worked in practice: disrupting the customary gender relations of a combatant society to remove opposing men from their authoritative role and installing an imperial officer at the top of the hierarchy. [ABSTRACT FROM AUTHOR]

This cluster of articles explores the gendered history of the military in the Russian imperial and Soviet contexts during periods of imperial conquest, war, and their complex aftermaths. The cluster began at the 2021 ASEEES virtual convention, when the contributors joined the Zoom panel while their respective countries were in various stages of lockdown. Chronologically, the cluster stretches from the middle of the nineteenth century to the 1960s, with two articles on the Russian Empire and two covering the Soviet period. From the imperial borderlands of the Caucasus in the nineteenth century to the Nazi‐occupied western frontiers of the Soviet Union during the Second World War, ideas about appropriate feminine and masculine behavior shaped the enactment of and reactions to violence. Veterans of the Russo‐Japanese and Second World Wars drew on vocabularies of military masculinity to claim authority within their respective postwar societies. In this short introduction, we reflect on the relationship between gender history and military history and underline the importance of integrating the Russian/Soviet case into international historiographies of gender and war. [ABSTRACT FROM AUTHOR]

Mycobacteriophages are viruses that infect mycobacterial hosts such as Mycobacterium smegmatis and Mycobacterium tuberculosis. All mycobacteriophages characterized to date are dsDNA tailed phages, and have either siphoviral or myoviral morphotypes. However, their genetic diversity is considerable, and although sixty-two genomes have been sequenced and comparatively analyzed, these likely represent only a small portion of the diversity of the mycobacteriophage population at large. Here we report the isolation, sequencing and comparative genomic analysis of 18 new mycobacteriophages isolated from geographically distinct locations within the United States. Although no clear correlation between location and genome type can be discerned, these genomes expand our knowledge of mycobacteriophage diversity and enhance our understanding of the roles of mobile elements in viral evolution. Expansion of the number of mycobacteriophages grouped within Cluster A provides insights into the basis of immune specificity in these temperate phages, and we also describe a novel example of apparent immunity theft. The isolation and genomic analysis of bacteriophages by freshman college students provides an example of an authentic research experience for novice scientists.