Cholinergic input to, and cholinergic mechanisms within the lower lumbar (L6) and upper sacral (S1) spinal cord of rat may influence neuronal excitability and afferent transmission (Thor et al, 2000) and may provide the environment necessary for appropriate central nervous system control of bladder and bowel function. It is unclear, however, if cholinergic terminals and receptors are present in the L6 & S1 spinal segments of rat and when this may develop. Cholinergic mechanisms have been shown to alter sensory afferent transmission, enhance motoneuron excitability, induce plateau potentials via non-linear membrane properties in motoneurons and reveal oscillations in locomotor-related interneurons. The enhanced activity of sphincter motoneurons was attributed to non-linear properties during the continence phase of distention-evoked voiding in the decerebrate cat (Paroschy & Shefchyk, 2000). Candidate neurotransmitters inducing non-linear properties in cat sphincter motoneurons are 5-HT (Paroschy & Shefchyk, 2000) and acetylcholine via motoneuron axon collaterals (Sasaki, 1994) and other spinal sources. We have established using the antibody to the vesicular acetylcholine transporter (VAChT) that cholinergic terminals are present on ventrolateral Onuf (VLO), dorsomedial Onuf (DMO) motoneurons and parasympathetic preganglionic motoneurons (PGN) in the L6 and S1 rat spinal cord segments. Muscarinic receptor (M2), nicotinic-α4 and α7 receptor subunit immunoreactivity was also present on Onuf motoneurons and in regions dorsal to the PGN. One source of the cholinergic puncta on Onuf motoneurons may be from motoneuron axon collaterals which we observed on a postnatal day 15 VLO motoneuron. Cholinergic terminals were observed on vasoactive intestinal polypeptide-immunoreactive (VIP) afferents, interneurons in the intermediolateral (IML) region and perhaps on other afferents in the lateral and medial collateral pathway of L6 and S1 spinal segments. In the ventral horn, the cholinergic puncta and receptors appear to have a mature distribution around two weeks postnatal and the cholinergic terminals appeared to have a mature distribution in the IML region by three weeks postnatal. Using whole cell patch clamp recording techniques and thick slices of the L6 and S1 rat spinal cord, we observed excitatory responses of ventral horn neurons and motoneurons to carbachol (10-50 μM), a non-specific cholinergic agonist. Ventral horn neurons (postnatal day 8- 16) exhibited prolonged firing and prolonged depolarizations (plateau potentials) beyond the duration of the applied excitatory input from cholinergic (n=6/33) and other (n= 4/37) neurotransmitter systems. In a selection of the neurons with plateau potentials, the L-type calcium current played a role in the plateau production (n=5/5) and low frequency oscillations (n=2/2) as revealed by nifedipine. Postnatally, the voiding reflex changes from a perineal-evoked reflex, to the adult bladder-bladder reflex. Cholinergic input may be responsible in part for the bursting activity of the external urethral sphincter and the activation of the bladder, which is required for complete voiding reflexes in the adult rat. Plateau potentials and enhanced excitability due to cholinergic mechanisms could render inessential a constant excitatory drive that is required in the perineal-evoked voiding reflex in the neonatal rat and may underlie changes in the voiding reflexes that occur during postnatal development. / February 2006

Aim: More and more organizations worldwide want to develop products for global markets. At the same time, they need to make their products available in the global market to be competitive. One of today's trends to solve this problem of making products in the global market is by involving logistics to manage complex distribution requirements. Organizations have developed strategic alliances with companies all over the world to manage their logistics operations network. (www.chrobinson.com). My research was aimed at understanding the coordination of logistics activities at the terminal.   Method: I based my study on a combination of descriptive and exploratory type. As regards descriptive I presented my data collected in a descriptive analysis. Also I used the exploratory research to know exactly the implementation of logistics activities at Schenker's terminal and also to observe the activities, conduct interviews and administer questionnaires.   Result & Conclusions: The major results of my findings revealed that the existing management procedure of the outbound logistics system at Schenker terminal which involves material handling, transportation, distribution, cross-docking, customer service and information systems could not be seen as lean and agile. This is because of the existence of many problems faced by the terminal such as congestion, flows inefficiencies, excess scrap, too much manual documentation,  delays in deliveries, damages, poor customer service, return goods, idle equipment (forklift and trucks) and personal and high cost of operations.   Suggestions for future research: The study is limited in the sense that it does not include the whole supply chain; the terminal is just a part in the supply chain and whatever problems that are encountered are not experienced in the whole supply chain. This could lead to a broader basis of a future research project.

This dissertation considers daily operations management for a fleet of trucks providing container pickup and delivery service to a port. Truck congestion at access points for ports may lead to serious inefficiencies in drayage operations, and the resultant cost impact to the intermodal supply chain can be significant. Recognizing that port congestion is likely to continue to be a major problem for drayage operations given the growing volume of international containerized trade, this research seeks to develop optimization approaches for maximizing the productivity of drayage firms operating at congested seaports. Specifically, this dissertation addresses two daily drayage routing and scheduling problems. In the first half of this dissertation, we study the problem of managing a fleet of trucks providing container pickup and delivery service to a port facility that experiences different access wait times depending on the time of day. For this research, we assume that the wait time can be estimated by a deterministic function. We develop a time-constrained routing and scheduling model for the problem that incorporates the time-dependent congestion delay function. The model objective is to find routes and schedules for drayage vehicles with minimum total travel time, including the waiting time at the entry to the port due to congestion. We consider both exact and heuristic solution approaches for this difficult optimization problem. Finally, we use the framework to develop an understanding of the potential impact of congestion delays on drayage operations, and the value of planning with accurate delay information. In the second half of this dissertation, we study methods for managing a drayage fleet serving a port with an appointment-based access control system. Responding to growing access congestion and its resultant impacts, many U.S. port terminals have implemented appointment systems, but little is known about the impact of such systems on drayage productivity. To address this knowledge gap, we develop a drayage operations optimization approach based on a column generation integer programming heuristic that explicitly models a time-slot port access control system. The approach determines pickup and delivery sequences with minimum transportation cost. We use the framework to develop an understanding of the potential efficiency impacts of access appointment systems on drayage operations. Findings indicate that the set of feasible drayage tasks and the fleet size required to complete them can be quite sensitive to small changes in time-slot access capacities at the port.

We consider two classes of stochastic programming models which are motivated by two applications related to the field of aviation. The first problem we consider is the network capacity planning problem, which arises in capacity planning of systems with network structures, such as transportation terminals, roadways and telecommunication networks. We study this problem in the context of airport terminal capacity planning. In this problem, the objective is to determine the optimal design and expansion capacities for different areas of the terminal in the presence of uncertainty in future demand levels and expansion costs, such that overall passenger delay is minimized. We model this problem as a nonlinear multistage stochastic integer program with a multicommodity network flow structure. The formulation requires the use of time functions for maximum delays in passageways and processing stations, for which we derive approximations that account for the transient behavior of flow. The deterministic equivalent of the developed model is solved via a branch and bound procedure, in which a bounding heuristic is used at the nodes of the branch and bound tree to obtain integer solutions. In the second study, we consider the project portfolio optimization problem. This problem falls in the class of stochastic programs in which times of uncertainty realizations are dependent on the decisions made. The project portfolio optimization problem deals with the selection of research and development (R&D) projects and determination of optimal resource allocations for the current planning period such that the expected total discounted return or a function of this expectation for all projects over an infinite time horizon is maximized, given the uncertainties and resource limitations over a planning horizon. Accounting for endogeneity in some parameters, we propose efficient modeling and solution approaches for the resulting multistage stochastic integer programming model. We first develop a formulation that is amenable to scenario decomposition, and is applicable to the general class of stochastic problems with endogenous uncertainty. We then demonstrate the use of the sample average approximation method in solving large scale problems of this class, where the sample problems are solved through Lagrangian relaxation and lower bounding heuristics.

The air transportation system plays a crucial role in modern society, comprising a major industrial sector as well as a key driver for adjacent economies. Moreover, it is a prime enabler of the modern way of life, characterized by access to products and services from around the world, and access to remote locations. Therefore there is a strong incentive to maintain the system and promote its growth. None the less, important challenges have plagued civil aviation, particularly the commercial aviation sector. On one hand, demand for air travel has grown dramatically and at an accelerated pace, in part due to the deregulation of airlines in 1978, providing airlines with the freedom to arrange their operational schedule freely and compete for markets. The dynamic nature of demand and its fast-paced growth contrasts with the relative rigidity of air transportation infrastructure development and the sluggish evolution of its operational architecture. The supply-demand mismatch that results has led to degradation in system efficiency, excessive delays, and substantial economic losses. This phenomenon is particularly exacerbated in the terminal area of major airports which have inevitably become operational choke points. On the other hand the environmental impact of air transportation, embodied primarily by the emissions and noise caused by aircraft operations, has also grown as a result of the increase in aviation activity, and has therefore become a major issue of public interest. Airport communities experience said environmental impact most intensely, particularly those associated with bottleneck airports, and thus represent a uniquely strong force opposing further expansion of air transportation in these areas where it is most needed. Past efforts to address these challenges have been notably stovepiped and have failed to recognize the importance of the relationship between the operational nature of the system and its environmental impact. Only recently have research efforts begun to incorporate a joint view of the operational-environmental problem that attempts to formulate solutions accordingly. However, the state of the art has yet to answer some of the most fundamental questions. First, the relationship between operational and environmental elements has not been quantified conclusively. Doing so is vital to understand the operational-environmental nature of terminal areas before any solutions can be considered. Secondly, many different types of solution alternatives have been proposed, such as the construction of new runways, redesign of operational procedures, introduction of advanced aircraft concepts, and transformation of airspace capabilities. However, a direct comparison between dissimilar alternatives that accounts for operational and environmental issues is rarely found, and yet remains crucial in the formulation of a solution portfolio. More importantly, the additive and countervailing interactions that different solutions have on each other are widely recognized but remain, for the most part, unknown. Because all solutions under consideration require an extended period of time to develop and represent very large economic commitments, the selection of a portfolio demands a careful look at the future to determine the adequate measures that should be pursued in the present. In response to this methodological need, this thesis proposes a strategic planning approach to investigate the operational-environmental nature of the air transportation system, as well as the adequacy of solution alternatives for terminal areas in the formulation of a portfolio. The state of the art currently incorporates elements of strategic planning, but has yet to address two important methodological gaps. First, the inherent systemic complexity of airport performance obfuscates its quantitative characterization, which is paramount in attaining adequate insight and understanding to support informed strategic decision-making in the selection of terminal area solutions. Second, there is significant uncertainty about the evolution of the aviation demand and its operational context, making the use of forecasts grossly inadequate for this application. A scenario-based approach is used in its place, but the current frameworks for the generation, evaluation, and selection of an adequate scenario set currently lack traceability and methodological rigor. To address the first gap, this thesis proposes the use of well established statistical analysis techniques, leveraging on recent developments in interactive data visualization capabilities, to quantitatively characterize the interactions, sensitivities, and tradeoffs prevalent in the complex behavior of airport operational and environmental performance. Within the strategic airport planning process, this approach is used in the assessment of airport performance under current/reference conditions, as well as in the evaluation of terminal area solutions under projected demand conditions. More specifically, customized designs of experiments are utilized to guide the intelligent selection and definition of modeling and simulation runs that will yield greater understanding, insight, and information about the inherent systemic complexity of a terminal area, with minimal computational expense. Regression analysis leverages the creation of response surface equations that explicitly and quantitatively capture the behavior of system metrics of interest as functions of factors or terminal area solutions. This explicit mathematical characterization enables a variety of interactive visualization schemes that allow analysts and decision makers to confirm or rectify expected patterns of behavior, and to discover the unknown and the unexpected. Said visualization schemes are also instrumental in communicating, in a very direct and succinct fashion, complex relationships, sensitivities, tradeoffs, and interactions, that would be otherwise too complex to explain or communicate transparently. More importantly, this approach provides a rigorous and formalized mathematical framework within which the statistical significance of different factors or terminal area solutions can be quantitatively and explicitly assessed, primarily by means of statistical hypotheses testing of regression parameter estimates, such as the analysis of variance, or the t-statistic test. This proposed approach does not suggest a new strategic planning process, but rather improves specific steps pertaining to performance assessments, and builds upon established practices and the recommended planning process for airports to leverage on the decades of experience supporting the existing strategic airport planning paradigm. On the other hand, the proposed approach recognizes the methodological limitations and constraints that lead to the lack of terminal area performance characterization within the strategic planning process, embodied primarily by computational constraints and unmanageable systemic complexity, and directly addresses these shortcomings by incorporating mature statistical analysis techniques into key steps of said process. In turn, the proposed approach represents a novel adaptation of the strategic airport planning process that results in greater knowledge, insight, and understanding, at a resource cost comparable to current airport planning practices. As such, this proposed approach is demonstrated using the Atlanta Hartsfield-Jackson International Airport as a representative test case, and constitutes a contribution to strategic airport planning given that it supports strategic decision making by revealing, at an acceptable analysis and computational expense, the various sensitivities, interactions, and tradeoffs of interest in operational-environmental performance that would otherwise remain implicit and obfuscated by systemic complexity. For the research documented in this thesis, a modeling and simulation environment was created featuring three primary components. First, a generator of schedules of operations, based primarily on previous work on aviation demand characterization, whereby growth factors and scheduling adjustment algorithms are applied on appropriate baseline schedules so as to generate notional operational sets representative of consistent future demand conditions. The second component pertains to the modeling and simulation of aircraft operations, defined by a schedule of operations, on the airport surface and within its terminal airspace. This component is a discrete event simulator for multiple queuing models that captures the operational architecture of the entire terminal area along with all the necessary operational logic pertaining to simulated ATC functions, rules, and standard practices. The third and final component is comprised of legacy aircraft performance, emissions and dispersion, and noise exposure modeling tools, that use the simulation history of aircraft movements to generate estimates of fuel burn, emissions, and noise. A set of designed modeling and simulation experiments were conducted to examine the interactions between exogenous and endogenous factors, as well as their main and quadratic effect, on operational metrics such as delay, and on fuel burn as the primary environmental metrics. Results show that for a gate-hold scheme used to manage surface traffic density, the departure queue threshold features a statistically significant interaction with the increasing number of operations, but that otherwise the relative percent change in the number of operations remains as the predominant exogenous factor driving operational and environmental performance. A separate design of modeling and simulation experiments was conducted to test the statistical significance of proposed geographical regional categories that could potentially be used to classify operations and capture operational demand characteristics such as fleet mix, time of day distribution, and arrival/departure route distribution. Results show that whereas the proposed categorization is statistically significant for a few metric of interest, marginally significant for others, and not statistically significant for most metrics, the proposed regional classification scheme is not appropriate for operational demand characterization. The implementation of the proposed approach for the assessment of terminal area solutions incorporates the use of discrete response surface equations, and eliminates the use of quadratic terms that have no practical significance in this context. Rather, attention is entire placed on the main effects of different terminal area solutions, namely additional airport infrastructure, operational improvements, and advanced aircraft concepts, modeled as discrete independent variables for the regression model. Results reveal that an additional runway and a new international terminal, as well as reduced aircraft separation, have a major effect on all operational metrics of interest. In particular, the additional runway has a dominant effect for departure delay metrics and gate hold periods, with moderate interactions with respect to separation reduction. On the other hand, operational metrics for arrivals are co-dependent on additional infrastructure and separation reduction, featuring marginal improvements whenever these two solutions are implemented in isolation, but featuring a dramatic compounding effect when implemented in combination. The magnitude of these main effects for departures and of the interaction between these solutions for arrivals is confirmed through appropriate statistical significance testing. Finally, the inclusion o advanced aircraft concepts is shown to be most beneficial for airborne arrival operations and to a lesser extent for arrival ground movements. More specifically, advanced aircraft concepts were found to be primarily responsible for reductions in volatile organic compounds, unburned hydrocarbons, and particulate matter in this flight regime, but featured relevant interactions with separation reduction and additional airport infrastructure. To address the second gap, pertaining to the selection of scenarios for strategic airport planning, a technique for risk-based scenario construction, evaluation, and selection is proposed, incorporating n-dimensional dependence tree probability approximations into a morphological analysis approach. This approach to scenario construction and downselection is a distinct and novel contribution to the scenario planning field as it provides a mathematically and explicitly testable definition for an H parameter, contrasting with the qualitative alternatives in the current state of the art, which can be used in morphological analysis for scenario construction and downselection. By demonstrating that dependence tree probability product approximations are an adequate aggregation function, probability can be used for scenario construction and downselection without any mathematical or methodological restriction on the resolution of the probability scale or the number of morphological alternatives that have previously plagued probabilization and scenario downselection approaches. In addition, this approach requires expert input elicitation that is comparable or less than the current state of the art practices.

Although the region has acquired expertise in the physical dimensions of rapid transit implementation, that expertise has not translated into a better understanding of social impacts on communities which host this regional amenity. The Broadway Station area is such a community. Although the City of Vancouver is responsible for planning the Broadway Station area community, many provincial decisions have had far-reaching consequences and do not correspond with municipal policy for the community. The province has introduced region-serving programs and facilities into the community despite municipal policy that the Broadway Station area would not serve a regional role. As a consequence, the community is becoming increasingly unlivable. There is a de facto policy vacuum. Moreover, there is a lack of coordination and an absence of protocols for managing and sharing data. There is little, if any, coordination of senior government actions, and the actions of various levels of government and their agencies have resulted in the Broadway Station Area failing to achieve the goal of community livability, for the resident community. The City of Vancouver, within which the case study station resides, has so far been unable to respond to the challenge that the station poses. The degree to which the station area is becoming dysfunctional is not known to the city. Consequently, the thesis question "Is the Broadway Station Area worse off than before SkyTrain" posed a significant challenge. In addition to a review of the case study planning process, which was conducted by the thesis researcher in the latter half of 1996, this thesis adds interviews with professional planners and a limited empirical study to answer the thesis question. By looking at a limited number of key census indicators, and cross comparing that with other data sources, the thesis found that the community's perception has merit, although a great deal more data must be compiled. To better understand what works in the Canadian context of transit-oriented planning, we need to support ongoing qualitative community planning with the empirical work that would assist in monitoring the effect of policies and program implementation and can address the dynamism of this regional transit node.

Tom Steer, senior associate on the Gautrain Architects Joint Venture states that "When people arrive in cities with well-organised transport networks, they breathe a sigh of relief. The identity of the transport system forms an integral part of the city's identity and the way it is perceived internationally." (Theunissen, 2009: 22) Mokena Makeka of Makeka Design Laboratory agrees saying "The role that transport facilities play in the creation of an identity for both the industry itself and the city is essential, and one that is often underplayed in this country" (Theunissen, 2009: 22). In South Africa today, the public transport industry is perceived negatively by a large portion of the population. This perception is largely rooted in the troubled history of South Africa with Apartheid playing a major role in the formulation of such perceptions. In addition, issues surrounding lack of government funding, supporting infrastructure, safety, reliability, comfort, accessibility and a general state of disrepair hinder the progress within the system. This has resulted in a system that is severely underutilized by the middle to high income population, creating overcrowding on roads through the use of private motor vehicles, and the unsustainable nature of South Africa's transport system as a whole. This study focuses on the role of identity in architecture, exploring the concept of architecture as a catalytic instrument in the creation, and identification of identity, and how this can be applied to transform the public transport industry as a whole. The intention is to identify and explain the important principles and elements that inform the success of a transport interchange, and how a building can redeem itself and create a new identity. It is clear through the study that infrastructure is required in the public transport industry. This dissertation looks at the design of a modal interchange facility which seeks to appeal to a wider socio-economic group, and in turn create a more sustainable system as a whole. One must acknowledge that for any significant change to occur, more than just architecture is required, as architecture in isolation, cannot address all the issues. Identity is formulated through a number of elements, not only built form. The approach will have to be a holistic one and a broad remodelling of the current system is required. Modal interchanges do however form the backbone to this process and act as a vital catalyst in the transformation of the industry. / Thesis (M.Arch.)-University of KwaZulu-Natal, Durban, 2012.

This dissertation examines the role that public infrastructure development at the Port of Durban has had on the KwaZulu-Natal's auto sector. In essence this paper unpacks the debate surrounding public spending directed at promoting specific industry outcomes. To this end, the auto industry is examined in terms of its export-orientated growth since the inception of the car terminus. The auto industry provides an excellent case study, as there is considerable public and private sector concern in this sphere. This paper analyses the role of local and national government as well as nongovernmental role players in planning expenditure for the car terminal. The limited amount of formal literature in this field has informed the structure of this paper, making it important that some measure of efficiency benchmarking be included in this study. This has been done so of the role of the car terminal in the logistic value chains of the KZN auto industry could be examined. This in turn aided in the understanding of the role of the terminal as a conduit for inputs used in local production as well as the impact it has (or hasn't) had on export-orientated growth within the industry. / Thesis (M.Dev.Studies)-University of KwaZulu-Natal, Durban, 2005.

Cholinergic input to, and cholinergic mechanisms within the lower lumbar (L6) and upper sacral (S1) spinal cord of rat may influence neuronal excitability and afferent transmission (Thor et al, 2000) and may provide the environment necessary for appropriate central nervous system control of bladder and bowel function. It is unclear, however, if cholinergic terminals and receptors are present in the L6 & S1 spinal segments of rat and when this may develop. Cholinergic mechanisms have been shown to alter sensory afferent transmission, enhance motoneuron excitability, induce plateau potentials via non-linear membrane properties in motoneurons and reveal oscillations in locomotor-related interneurons. The enhanced activity of sphincter motoneurons was attributed to non-linear properties during the continence phase of distention-evoked voiding in the decerebrate cat (Paroschy & Shefchyk, 2000). Candidate neurotransmitters inducing non-linear properties in cat sphincter motoneurons are 5-HT (Paroschy & Shefchyk, 2000) and acetylcholine via motoneuron axon collaterals (Sasaki, 1994) and other spinal sources. We have established using the antibody to the vesicular acetylcholine transporter (VAChT) that cholinergic terminals are present on ventrolateral Onuf (VLO), dorsomedial Onuf (DMO) motoneurons and parasympathetic preganglionic motoneurons (PGN) in the L6 and S1 rat spinal cord segments. Muscarinic receptor (M2), nicotinic-α4 and α7 receptor subunit immunoreactivity was also present on Onuf motoneurons and in regions dorsal to the PGN. One source of the cholinergic puncta on Onuf motoneurons may be from motoneuron axon collaterals which we observed on a postnatal day 15 VLO motoneuron. Cholinergic terminals were observed on vasoactive intestinal polypeptide-immunoreactive (VIP) afferents, interneurons in the intermediolateral (IML) region and perhaps on other afferents in the lateral and medial collateral pathway of L6 and S1 spinal segments. In the ventral horn, the cholinergic puncta and receptors appear to have a mature distribution around two weeks postnatal and the cholinergic terminals appeared to have a mature distribution in the IML region by three weeks postnatal. Using whole cell patch clamp recording techniques and thick slices of the L6 and S1 rat spinal cord, we observed excitatory responses of ventral horn neurons and motoneurons to carbachol (10-50 μM), a non-specific cholinergic agonist. Ventral horn neurons (postnatal day 8- 16) exhibited prolonged firing and prolonged depolarizations (plateau potentials) beyond the duration of the applied excitatory input from cholinergic (n=6/33) and other (n= 4/37) neurotransmitter systems. In a selection of the neurons with plateau potentials, the L-type calcium current played a role in the plateau production (n=5/5) and low frequency oscillations (n=2/2) as revealed by nifedipine. Postnatally, the voiding reflex changes from a perineal-evoked reflex, to the adult bladder-bladder reflex. Cholinergic input may be responsible in part for the bursting activity of the external urethral sphincter and the activation of the bladder, which is required for complete voiding reflexes in the adult rat. Plateau potentials and enhanced excitability due to cholinergic mechanisms could render inessential a constant excitatory drive that is required in the perineal-evoked voiding reflex in the neonatal rat and may underlie changes in the voiding reflexes that occur during postnatal development.

Cholinergic input to, and cholinergic mechanisms within the lower lumbar (L6) and upper sacral (S1) spinal cord of rat may influence neuronal excitability and afferent transmission (Thor et al, 2000) and may provide the environment necessary for appropriate central nervous system control of bladder and bowel function. It is unclear, however, if cholinergic terminals and receptors are present in the L6 & S1 spinal segments of rat and when this may develop. Cholinergic mechanisms have been shown to alter sensory afferent transmission, enhance motoneuron excitability, induce plateau potentials via non-linear membrane properties in motoneurons and reveal oscillations in locomotor-related interneurons. The enhanced activity of sphincter motoneurons was attributed to non-linear properties during the continence phase of distention-evoked voiding in the decerebrate cat (Paroschy & Shefchyk, 2000). Candidate neurotransmitters inducing non-linear properties in cat sphincter motoneurons are 5-HT (Paroschy & Shefchyk, 2000) and acetylcholine via motoneuron axon collaterals (Sasaki, 1994) and other spinal sources. We have established using the antibody to the vesicular acetylcholine transporter (VAChT) that cholinergic terminals are present on ventrolateral Onuf (VLO), dorsomedial Onuf (DMO) motoneurons and parasympathetic preganglionic motoneurons (PGN) in the L6 and S1 rat spinal cord segments. Muscarinic receptor (M2), nicotinic-α4 and α7 receptor subunit immunoreactivity was also present on Onuf motoneurons and in regions dorsal to the PGN. One source of the cholinergic puncta on Onuf motoneurons may be from motoneuron axon collaterals which we observed on a postnatal day 15 VLO motoneuron. Cholinergic terminals were observed on vasoactive intestinal polypeptide-immunoreactive (VIP) afferents, interneurons in the intermediolateral (IML) region and perhaps on other afferents in the lateral and medial collateral pathway of L6 and S1 spinal segments. In the ventral horn, the cholinergic puncta and receptors appear to have a mature distribution around two weeks postnatal and the cholinergic terminals appeared to have a mature distribution in the IML region by three weeks postnatal. Using whole cell patch clamp recording techniques and thick slices of the L6 and S1 rat spinal cord, we observed excitatory responses of ventral horn neurons and motoneurons to carbachol (10-50 μM), a non-specific cholinergic agonist. Ventral horn neurons (postnatal day 8- 16) exhibited prolonged firing and prolonged depolarizations (plateau potentials) beyond the duration of the applied excitatory input from cholinergic (n=6/33) and other (n= 4/37) neurotransmitter systems. In a selection of the neurons with plateau potentials, the L-type calcium current played a role in the plateau production (n=5/5) and low frequency oscillations (n=2/2) as revealed by nifedipine. Postnatally, the voiding reflex changes from a perineal-evoked reflex, to the adult bladder-bladder reflex. Cholinergic input may be responsible in part for the bursting activity of the external urethral sphincter and the activation of the bladder, which is required for complete voiding reflexes in the adult rat. Plateau potentials and enhanced excitability due to cholinergic mechanisms could render inessential a constant excitatory drive that is required in the perineal-evoked voiding reflex in the neonatal rat and may underlie changes in the voiding reflexes that occur during postnatal development.