The objective of this study was to determine how neurons within the right atrial ganglionated plexus (RAGP) and posterior atrial ganglionated plexus (PAGP) interact to modulate right atrial chronotropic, dromotropic, and inotropic function, particularly with respect to their extracardiac vagal and sympathetic efferent neuronal inputs. Surgical ablation of the PAGP (PAGPx) attenuated vagally mediated bradycardia by 26%; it reduced heart rate slowing evoked by vagal stimulation superimposed on sympathetically mediated tachycardia by 36%. RAGP ablation (RAGPx) eliminated vagally mediated bradycardia, while retaining the vagally induced suppression of sympathetic-mediated tachycardia (-83%). After combined RAGPx and PAGPx, vagal stimulation still reduced sympathetic-mediated tachycardia (-47%). After RAGPx alone and after PAGPx alone, stimulation of the vagi still produced negative dromotropic effects, although these changes were attenuated compared with the intact state. Negative dromotropic responses to vagal stimulation were further attenuated after combined ablation, but parasympathetic inhibition of atrioventricular nodal conduction was still demonstrable in most animals. Finally, neither RAGPx nor PAGPx altered autonomic regulation of right atrial inotropic function. These data indicate that multiple aggregates of neurons within the intrinsic cardiac nervous system are involved in sinoatrial nodal regulation. Whereas parasympathetic efferent neurons regulating the right atrium, including the sinoatrial node, are primarily located within the RAGP, prejunctional parasympathetic-sympathetic interactions regulating right atrial function also involve neurons within the PAGP.

The purpose of this study was to determine how Indiana Agricultural Science and Business (ASB) teachers perceived the impact of integrating science on agricultural education programs. The population consisted of all Indiana ASB teachers employed during the fall 1999 semester (N = 243). The Integrating Science Survey Instrument developed by Thompson (1996) was used to identify the perceptions of the ASB instructors. From the data it was concluded that many of Indiana's Agricultural Science and Business instructors have responded positively to the call for the integration of science into the agricultural education curriculum. As a result of their efforts, over half of the teachers reported their students receive science credit toward high school graduation after successfully completing one or more of the approved Agricultural Science and Business courses. Indiana Agricultural Science and Business teachers agreed they felt prepared to teach integrated biological science concepts but that it required more preparation time than before they integrated scientific concepts into their agricultural education curriculum. Teachers identified specific barriers to integrating scientific concepts into their programs as a lack of appropriate equipment, and a lack of adequate funding to support their integration efforts.

To determine the activity characteristics displayed by different subpopulations of neurons in a single intrinsic cardiac ganglionated plexus, the behaviour and co‐ordination of activity generated by neurons in two loci of the right atrial ganglionated plexus (RAGP) were evaluated in 16 anaesthetized dogs during basal states as well as in response to increasing inputs from ventricular sensory neurites. These sub‐populations of right atrial neurons received afferent inputs from sensory neurites in both ventricles that were responsive to local mechanical stimuli and the nitric oxide donor nitroprusside. Neurons in at least one RAGP locus were activated by epicardial application of veratridine, bradykinin, the β1‐adrenoceptor agonist prenaterol or glutamate. Epicardial application of angiotensin II, the selective β2‐adrenoceptor agonist terbutaline and selective α‐adrenoceptor agonists elicited inconsistent neuronal responses. The activity generated by both populations of atrial neurons studied over 5 min periods during basal states displayed periodic coupled behaviour (cross‐correlation coefficients of activities that reached, on average, 0·88 ± 0·03; range 0·71–1) for 15–30 s periods of time. These periods of coupled activity occurred every 30–50 s during basal states, as well as when neuronal activity was enhanced by chemical activation of their ventricular sensory inputs. These results indicate that neurons throughout one intrinsic cardiac ganglionated plexus receive inputs from mechano‐ and chemosensory neurites located in both ventricles. That such neurons respond to multiple chemical stimuli, including those liberated from adjacent adrenergic efferent nerve terminals, indicates the complexity of the integrative processing of information that occurs within the intrinsic cardiac nervous system. It is proposed that the interdependent activity displayed by populations of neurons in different regions of one intrinsic cardiac ganglionated plexus, responding as they do to multiple cardiac sensory inputs, forms the basis for integrated regional cardiac control.

The intrinsic cardiac nervous system receives reduced input from extracardiac sympathetic efferent neurons after transplantation and inconsistent input from parasympathetic efferent preganglionic neurons. These heterogeneous neuronal inputs are not reflected in heart rate variability or ventricular beta-adrenergic receptor function. Transplanted angiotensin II-sensitive intrinsic cardiac neurons exert greater cardiac control than do nicotine-sensitive ones. The intrinsic cardiac nervous system remodels itself after cardiac transplantation, and this indicates that direct assessment of extracardiac and intrinsic cardiac neuronal behavior is required to fully understand cardiac control after transplantation.

Science teachers who taught in a high school with an Agricultural Science and Technology Program were the focus of this study to determine their support for integrating science into Agricultural Education Programs. Results indicated that science teachers have responded positively to the call to integrate science into the agricultural education curriculum. The participants agreed that agriculture is an applied science and students are more aware of the science connections and learn more through an integrated curriculum in agriculture. A majority of the science teachers agreed that teacher preparation programs should provide instruction on how to integrate science, and student teachers should be placed in programs that promote integration. Science teachers believed that integrating science in agricultural education would contribute to educational reform by helping students meet state standards. According to the science teachers, barriers to integrating science included lack of equipment, funds, workshops, and the science teachers' lack of an agriculture background. The respondents agreed the science and agriculture programs have something to offer each other and would benefit students. However, one third of the teachers indicated a neutral response and one third disagreed that the science and agriculture departments worked together in a collaborative effort in their school.