6,403 research outputs found
Why Intensive Agriculturalists Have Higher Fertility: A Household Energy Budget Approach
It is widely held that human population growth rates began to increase markedly after the Pleistocene/Holocene transition largely as a consequence of the adoption of agriculture and sedentism. A common explanation for this increase in growth rates has been that circumstances associated with food production and/or the accompanying decrease in mobility allowed for higher fertility rates, but over the past decade a number of empirical studies and simulation analyses have revealed that the relationship between mode of subsistence and fertility is more complex than had previously been realized
Reframing Systems Disasters With Three Perspectives of organizational Culture
This paper presents the major literature on systems disasters and how organizational culture is portrayed in this literature. The paper then outlines the three cultural perspectives used by Martin 2002 to describe organizational cultures: integration, differentiation, and fragmentation. The paper explores show these perspectives influence interpretations about the disasters described. The paper concludes that the effect of an organization’s culture on safety, reliability, and disasters can be fully understood only when all three perspectives are applied
Functional inaccessibility of quiescent herpes simplex virus genomes
BACKGROUND: Newly delivered herpes simplex virus genomes are subject to repression during the early stages of infection of human fibroblasts. This host defence strategy can limit virus replication and lead to long-term persistence of quiescent viral genomes. The viral immediate-early protein ICP0 acts to negate this negative regulation, thereby facilitating the onset of the viral replication cycle. Although few mechanistic details are available, the host repression machinery has been proposed to assemble the viral genome into a globally inaccessible configuration analogous to heterochromatin, blocking access to most or all trans-acting factors. The strongest evidence for this hypothesis is that ICP0-deficient virus is unable to reactivate quiescent viral genomes, despite its ability to undergo productive infection given a sufficiently high multiplicity of infection. However, recent studies have shown that quiescent infection induces a potent antiviral state, and that ICP0 plays a key role in disarming such host antiviral responses. These findings raise the possibility that cells containing quiescent viral genomes may be refractory to superinfection by ICP0-deficient virus, potentially providing an alternative explanation for the inability of such viruses to trigger reactivation. We therefore asked if ICP0-deficient virus is capable of replicating in cells that contain quiescent viral genomes. RESULTS: We found that ICP0-deficient herpes simplex virus is able to infect quiescently infected cells, leading to expression and replication of the superinfecting viral genome. Despite this productive infection, the resident quiescent viral genome was neither expressed nor replicated, unless ICP0 was provided in trans. CONCLUSION: These data document that quiescent HSV genomes fail to respond to the virally modified host transcriptional apparatus or viral DNA replication machinery provided in trans by productive HSV infection in the absence of ICP0. These results point to global repression as the basis for HSV genome quiescence, and indicate that ICP0 induces reactivation by overcoming this global barrier to the access of trans-acting factors
A comparison of performance enhancing synergy among ultrafiltered yeast extracts and recombinant human serum albumin in CHO-K1 cells
Organizational Image Repair Tactics and Crisis Type: Implications for Crisis Response Strategy Effectiveness
Existing models of organizational crisis response effectiveness provide useful insights but are limited in terms of offering a guide for practitioners dealing with actual crisis situations. This analysis examines the relative effectiveness of image repair tactics based on differences in root causes of crisis events. Results suggest that certain image repair tactics are seen as the most and the least effective regardless of crisis type. At the same time, there were some differences across crisis types that could guide practitioner tactic choices. Limited results here and in past research raise questions about whether image repair tactic effectiveness can be usefully mapped to situational variables, such as audience or crisis type. This article concludes with discussion on this matter and suggestions for future research
Paths to QUALITY: A Child Care Quality Rating System for Indiana. Child Care Provider Focus Group Report
Application of complex and chemically-defined medium supplements toward cell line specific performance enhancement of biopharmaceutical production systems
- …