The Concordance Cosmic Star Formation Rate: Implications from and for the Supernova Neutrino and Gamma Ray Backgrounds

We constrain the Cosmic Star Formation Rate (CSFR) by requiring that massive stars produce the observed UV, optical, and IR light while at the same time not overproduce the Diffuse Supernova Neutrino Background as bounded by Super-Kamiokande. With the massive star component so constrained we then show that a reasonable choice of stellar Initial Mass Function and other parameters results in SNIa rates and iron yields in good agreement with data. In this way we define a `concordance' CSFR that predicts the optical SNII rate and the SNIa contribution to the MeV Cosmic Gamma-Ray Background. The CSFR constrained to reproduce these and other proxies of intermediate and massive star formation is more clearly delineated than if it were measured by any one technique and has the following testable consequences: (1) SNIa contribute only a small fraction of the MeV Cosmic Gamma-Ray Background, (2) massive star core-collapse is nearly always accompanied by a successful optical SNII, and (3) the Diffuse Supernova Neutrino Background is tantalizingly close to detectability.Comment: Improved discussion. Version accepted for publication in JCA

High-level Gpr56 expression is dispensable for the maintenance and function of hematopoietic stem and progenitor cells in mice

AbstractBlood formation by hematopoietic stem cells (HSCs) is regulated by a still incompletely defined network of general and HSC-specific regulators. In this study, we analyzed the role of G-protein coupled receptor 56 (Gpr56) as a candidate HSC regulator based on its differential expression in quiescent relative to proliferating HSCs and its common targeting by core HSC regulators. Detailed expression analysis revealed that Gpr56 is abundantly expressed by HSPCs during definitive hematopoiesis in the embryo and in the adult bone marrow, but its levels are reduced substantially as HSPCs differentiate. However, despite enriched expression in HSPCs, Gpr56-deficiency did not impair HSPC maintenance or function during steady-state or myeloablative stress-induced hematopoiesis. Gpr56-deficient HSCs also responded normally to physiological and pharmacological mobilization signals, despite the reported role of this GPCR as a regulator of cell adhesion and migration in neuronal cells. Moreover, Gpr56-deficient bone marrow engrafted with equivalent efficiency as wild-type HSCs in primary recipients; however, their reconstituting ability was reduced when subjected to serial transplantation. These data indicate that although GPR56 is abundantly and selectively expressed by primitive HSPCs, its high level expression is largely dispensable for steady-state and regenerative hematopoiesis

sj-docx-1-paq-10.1177_07349149241231097 – Supplemental material for Taking Care of Business and Doing Overtime: Teaching Research Methods in Public Affairs Curricula

Supplemental material, sj-docx-1-paq-10.1177_07349149241231097 for Taking Care of Business and Doing Overtime: Teaching Research Methods in Public Affairs Curricula by Kirsten L. Kinzer, John F. Brennan, Christopher R. Prentice and Jeffrey L. Brudney in Public Administration Quarterly</p

Responding to terrorism across the technological spectrum

In April 1994, the Army War College\u27s Strategic Studies Institute held its annual Strategy Conference. This year\u27s theme was The Revolution in Military Affairs: Defining an Army for the 21st Century. Dr. Bruce Hoffman presented this paper as part of a panel examining New Technologies and New Threats. Terrorism, of course, is not new. Hoffman warns, however, of the changing nature of terrorism. In the past, terrorists have been motivated by limited political and ideological objectives. Popular images fostered by terrorist events like the bombing of PAN AM Flight 103 and the attack on the Marine Barracks in Beirut notwithstanding, in the past the preponderance of terrorist attacks targeted specific individuals or small groups. The weapons of choice were the pistol, knife, and, on occasion, dynamite. Often the terrorist was a highly-trained individual, a professional in pursuit of specific political or ideological objectives. Hoffman warns that, by comparison, the terrorists of today and tomorrow are amateurs. Furthermore, they are likely to act from religious and racial convictions rather than radical political or ideological motivations. Their objective may be to kill large numbers of people. Indeed, they may want to annihilate an entire race or religious group. Not only are these amateurs less predictable and, therefore, more difficult to apprehend before the incident occurs, they have at their disposal lethal devices that range from the relatively simple fertilizer bomb to biologically-altered viruses. Military professionals and civilian planners must contend with warfare at every level. The threat posed by the changing nature of terrorism falls very much within their purview.https://press.armywarcollege.edu/monographs/1257/thumbnail.jp