Updated Nucleosynthesis Constraints on Unstable Relic Particles

We revisit the upper limits on the abundance of unstable massive relic particles provided by the success of Big-Bang Nucleosynthesis calculations. We use the cosmic microwave background data to constrain the baryon-to-photon ratio, and incorporate an extensively updated compilation of cross sections into a new calculation of the network of reactions induced by electromagnetic showers that create and destroy the light elements deuterium, he3, he4, li6 and li7. We derive analytic approximations that complement and check the full numerical calculations. Considerations of the abundances of he4 and li6 exclude exceptional regions of parameter space that would otherwise have been permitted by deuterium alone. We illustrate our results by applying them to massive gravitinos. If they weigh ~100 GeV, their primordial abundance should have been below about 10^{-13} of the total entropy. This would imply an upper limit on the reheating temperature of a few times 10^7 GeV, which could be a potential difficulty for some models of inflation. We discuss possible ways of evading this problem.Comment: 40 pages LaTeX, 18 eps figure

Social Control in Information Systems Development: A Negotiated Order Perspective

Control is vital for IS projects to be delivered on time and within budget. Control theory helps us better understand and explain control in information systems operations and development. However, simplistic notions about control do not correspond to how control actually works. We believe that a social perspective that sees controls as negotiated orders, and not just things imposed by controllers on controlees, better explains control of IS projects and operations. Through an interpretive case study of client—vendor control in the IS department of a large agricultural distributor, we show that: (1) control enactment involves the controller\u27s consideration of the social and organizational context as well as the controller\u27s intention. (2) Control enactment involves a socially constructed meaning and unintended consequences. (3) The control enactment also involves controlee intent either because of negotiation with the controller, or indirectly by way of alternative structures. Finally, (4) the control itself influences the controller and controlee in unanticipated ways. Seeing control as the result of negotiated orders between controllers and controlees contributes to control theory by suggesting that, in practice, negotiation, shaping and re-appropriation are necessary for successful control enactment

Inflammatory macrophage memory in nonsteroidal anti-inflammatory drug–exacerbated respiratory disease.

Background: Nonsteroidal anti-inflammatory drug–exacerbated respiratory disease (N-ERD) is a chronic inflammatory condition, which is driven by an aberrant arachidonic acid metabolism. Macrophages are major producers of arachidonic acid metabolites and subject to metabolic reprogramming, but they have been neglected in N-ERD. Objective: This study sought to elucidate a potential metabolic and epigenetic macrophage reprogramming in N-ERD. Methods: Transcriptional, metabolic, and lipid mediator profiles in macrophages from patients with N-ERD and healthy controls were assessed by RNA sequencing, Seahorse assays, and LC-MS/MS. Metabolites in nasal lining fluid, sputum, and plasma from patients with N-ERD (n = 15) and healthy individuals (n = 10) were quantified by targeted metabolomics analyses. Genome-wide methylomics were deployed to define epigenetic mechanisms of macrophage reprogramming in N-ERD. Results: This study shows that N-ERD monocytes/macrophages exhibit an overall reduction in DNA methylation, aberrant metabolic profiles, and an increased expression of chemokines, indicative of a persistent proinflammatory activation. Differentially methylated regions in N-ERD macrophages included genes involved in chemokine signaling and acylcarnitine metabolism. Acylcarnitines were increased in macrophages, sputum, nasal lining fluid, and plasma of patients with N-ERD. On inflammatory challenge, N-ERD macrophages produced increased levels of acylcarnitines, proinflammatory arachidonic acid metabolites, cytokines, and chemokines as compared to healthy macrophages. Conclusions: Together, these findings decipher a proinflammatory metabolic and epigenetic reprogramming of macrophages in N-ERD