Absence of siglec-H in MCMV infection elevates interferon alpha production but does not enhance viral clearance

Plasmacytoid dendritic cells (pDCs) express the I-type lectin receptor Siglec-H and produce interferon a (IFNa), a critical antiviral cytokine during the acute phase of murine cytomegalovirus (MCMV) infection. The ligands and biological functions of Siglec-H still remain incompletely defined in vivo. Thus, we generated a novel bacterial artificial chromosome (BAC)- transgenic ‘‘pDCre’’ mouse which expresses Cre recombinase under the control of the Siglec-H promoter. By crossing these mice with a Rosa26 reporter strain, a representative fraction of Siglec-H+ pDCs is terminally labeled with red fluorescent protein (RFP). Interestingly, systemic MCMV infection of these mice causes the downregulation of Siglec-H surface expression. This decline occurs in a TLR9- and MyD88-dependent manner. To elucidate the functional role of Siglec-H during MCMV infection, we utilized a novel Siglec-H deficient mouse strain. In the absence of Siglec-H, the low infection rate of pDCs with MCMV remained unchanged, and pDC activation was still intact. Strikingly, Siglec-H deficiency induced a significant increase in serum IFNa levels following systemic MCMV infection. Although Siglec-H modulates anti-viral IFNa production, the control of viral replication was unchanged in vivo. The novel mouse models will be valuable to shed further light on pDC biology in future studies

Security and polarization in Trump’s America: securitization and the domestic politics of threatening others

This article explores the relationship between foreign policy and domestic politics under Trump. We employ Gramscian theory to make sense of US foreign policy structures, conceptualizing the Trump administration as engaged in a discursive war of position over narratives of national identity and security. Second, we use securitization theory to conceptualize agency and change within this. We analyse 1200 official, opposition and media texts over 20 months following Trump's election. First, we consider Trump's attempted securitization of immigration. Second, we explore the counter-securitization of Trump as a threat to “progressive” America. Third, we analyse how Trump securitized the opposition, conflating the constructed threat posed by immigration with political elites. We show how this led to greater polarization of US political debate, which became underwritten by securitized language. Finally, we note security's referent differed for both groups, with Trump's ethnocentric “real” America opposed to the liberal America endorsed by his critics.

Southern Conservation Tillage

Improving tropical maize (Zea mays L.) tolerance for drought stress was initiated in 1991 in a fullsib recurrent selection program. This breeding program was initiated to compare two selection environments and to improve the yield stability of tropical maize under the north Florida drought-prone environments. Rainfed and irrigated plots were used to evaluate 140 fullsib families, along with four checks in a 12 X 12 partially balanced lattice design with four replications. Relative grain yield, plant and ear height leaf area, flower delay, canopy temperature, tassel weight, and drought index were used to select the fullsibs for the recombination phase. Yield reductions, ranging from 2 to 40% in the stress site, were mild due to appreciable rainfall. High variability existed among the fullsibs tested for grain yield. Irrigated grain yield ranged from 3987 to 8039 kg ha , and rainfed grain yield from 3066 to 7124 kg ha . A 15% selection pressureresulted in the advancement of 21 fullsibs from either site to the recombination process