Using video tutorials as a carrot-and-stick approach to learning

Traditional teaching styles practiced at universities do not generally suit all students\u27 learning styles. For a variety of reasons, students do not always engage in learning in the courses in which they are enrolled. New methods to create and deliver educational material are available, but these do not always improve learning outcomes. Acknowledging these truths and developing and delivering educational material that provides diverse ways for students to learn is a constant challenge. This study examines the use of video tutorials within a university environment in an attempt to provide a teaching model that is valuable to all students, and in particular to those students who are not engaging in learning. The results of a three-year study have demonstrated that the use of well-designed, assessment-focused, and readily available video tutorials have the potential to improve student satisfaction and grades by enabling and encouraging students to learn how they want, when they want, and at a pace that suits their needs

The role of ATP and adenosine in the control of hepatic blood flow in the rabbit liver in vivo

BACKGROUND: The role of adenosine and ATP in the regulation of hepatic arterial blood flow in the "buffer response" was studied in vitro and in a new in vivo model in the rabbit. The model achieves portal-systemic diversion by insertion of a silicone rubber prosthesis between the portal vein and inferior vena cava and avoids alterations in systemic haemodynamics. RESULTS: Hepatic arterial (HA) blood flow increased in response to reduced portal venous (PV) blood flow, the "buffer response", from 19.4 (3.3) ml min(-1 )100 g(-1 )to 25.6 (4.3) ml min(-1 )100 g(-1 )(mean (SE), p < 0.05, Student's paired t-test). This represented a buffering capacity of 18.7 (5.2) %. Intra-portal injections of ATP or adenosine (1 micrograms kg(-1)-0.5 mg kg(-1)) elicited immediate increases in HA blood flow to give -log ED(50 )values of 2.0 and 1.7 mg kg(-1 )for ATP and adenosine respectively. Injection of ATP and adenosine had no measurable effect on PV flow. In vitro, using an isolated dual-perfused rabbit liver preparation, the addition of 8-phenyltheophylline (10 MicroMolar) to the HA and PV perfusate significantly inhibited the HA response to intra-arterial adenosine and to mid-range doses of intra-portal or intra-arterial ATP (p < 0.001). CONCLUSIONS: It is suggested that HA vasodilatation elicited by ATP may be partially mediated through activation of P(1)-purinoceptors following catabolism of ATP to adenosine