83 research outputs found
Economics and the Political Economy of Adult Education
This chapter provides a critical overview of the contribution of economics to research and policy on adult education. It discusses three distinct political economy perspectives and links these to the shifting policy agenda related to adult education at the OECD over the last five decades. This is done to reveal the link between different political economy perspectives and the implications for analytical as well as political perspectives when approaching the study and policy of adult education. Some implications and challenges for research on adult education are discussed
PKQuest: a general physiologically based pharmacokinetic model. Introduction and application to propranolol
BACKGROUND: A "physiologically based pharmacokinetic" (PBPK) approach uses a realistic model of the animal to describe the pharmacokinetics. Previous PBPKs have been designed for specific solutes, required specification of a large number of parameters and have not been designed for general use. METHODS: This new PBPK program (PKQuest) includes a "Standardhuman" and "Standardrat" data set so that the user input is minimized. It has a simple user interface, graphical output and many new features: 1) An option that uses the measured plasma concentrations to solve for the time course of the gastrointestinal, intramuscular, intraperotineal or skin absorption and systemic availability of a drug – for a general non-linear system. 2) Capillary permeability limitation defined in terms of the permeability-surface area products. 4) Saturable plasma and tissue protein binding. 5) A lung model that includes perfusion-ventilation mismatch. 6) A general optimization routine using either a global (simulated annealing) or local (Powell) minimization applicable to all model parameters. RESULTS: PKQuest was applied to measurements of human propranolol pharmacokinetics and intestinal absorption. A meal has two effects: 1) increases portal blood flow by 50%; and 2) decreases liver metabolism by 20%. There is a significant delay in the oval propranolol absorption in fasting subjects that is absent in fed subjects. The oral absorption of the long acting form of propranolol continues for a period of more than 24 hours. CONCLUSIONS: PKQuest provides a new general purpose, easy to use, freely distributed and physiologically rigorous PBPK software routine
Effects of a single 20Â mg dose of letrozole on ovarian function post dominant follicle selection: an exploratory randomized controlled trial
The role of unintegrated DNA in HIV infection
Integration of the reverse transcribed viral genome into host chromatin is the hallmark of retroviral replication. Yet, during natural HIV infection, various unintegrated viral DNA forms exist in abundance. Though linear viral cDNA is the precursor to an integrated provirus, increasing evidence suggests that transcription and translation of unintegrated DNAs prior to integration may aid productive infection through the expression of early viral genes. Additionally, unintegrated DNA has the capacity to result in preintegration latency, or to be rescued and yield productive infection and so unintegrated DNA, in some circumstances, may be considered to be a viral reservoir. Recently, there has been interest in further defining the role and function of unintegrated viral DNAs, in part because the use of anti-HIV integrase inhibitors leads to an abundance of unintegrated DNA, but also because of the potential use of non-integrating lentiviral vectors in gene therapy and vaccines. There is now increased understanding that unintegrated viral DNA can either arise from, or be degraded through, interactions with host DNA repair enzymes that may represent a form of host antiviral defence. This review focuses on the role of unintegrated DNA in HIV infection and additionally considers the potential implications for antiviral therapy
Investigation on Newcastle Disease Virus (NDV), Infectious Bursal Disease Virus (IBDV) and Avian Poxvirus (APV) in magellanic penguins in Southern region of Brazil
Three-dimensional magnetic resonance imaging for the study of ovarian function in a bovine in vitro model
Magnetic resonance image attributes of the bovine ovarian follicle antrum during development and regression
- …