Development and verification of a laboratory for the emissions testing of locomotive engines

West Virginia University (WVU) currently has a Transportable Emissions Laboratory capable of measuring the exhaust constituents produced by a heavy duty diesel engine. The laboratory has the capability of measuring the exhaust constituents from a partial exhaust stream of a locomotive diesel engine. As the field of locomotive engine emissions testing broadens, it has become desirable for WVU to develop a laboratory that is capable of sampling the gaseous exhaust constituents produced by a locomotive engine from a raw, undiluted gas stream, in tandem with a partial flow dilution tunnel system for particulate matter. This document provides the design philosophy behind such a laboratory, as well as laboratory studies to verify the proper functionality of such system. Results from the study include the comparison of gaseous emissions between WVU\u27s Engines and Emissions Laboratory (EERL) full exhaust dilution tunnel system resulting in laboratory percentage differences of 3.4%, 3.57%, 0.33%, and 2.93% for hydrocarbons, oxides of nitrogen, carbon dioxide, and carbon monoxide, respectively. The partial flow dilution tunnel system was tested on a locomotive engine. The results from that study produced an overall system percentage difference of 4.8% for the line-haul mode of the first engine, 5.69% and 8.2% for the line-haul and switch mode, respectively for the second engine

Experience with Dynamic Reinforcement Rates Decreases Resistance to Extinction

The ability of organisms to detect reinforcer-rate changes in choice preparations is positively related to two factors: the magnitude of the change in rate and the frequency with which rates change. Gallistel (2012) suggested similar rate-detection processes are responsible for decreases in responding during operant extinction. Although effects of magnitude of change in reinforcer rate on resistance to extinction are well known (e.g., the partial-reinforcement-extinction effect), effects of frequency of changes in rate prior to extinction are unknown. Thus, the present experiments examined whether frequency of changes in baseline reinforcer rates impacts resistance to extinction. Pigeons pecked keys for variable-interval food under conditions where reinforcer rates were stable and where they changed within and between sessions. Overall reinforcer rates between conditions were controlled. In Experiment 1, resistance to extinction was lower following exposure to dynamic reinforcement schedules than to static schedules. Experiment 2 showed that resistance to presession feeding, a disruptor that should not involve change-detection processes, was unaffected by baseline-schedule dynamics. These findings are consistent with the suggestion that change detection contributes to extinction. We discuss implications of change-detection processes for extinction of simple and discriminated operant behavior and relate these processes to the behavioral-momentum based approach to understanding extinction

Temporal contingency

Contingency, and more particularly temporal contingency, has often figured in thinking about the nature of learning. However, it has never been formally defined in such a way as to make it a measure that can be applied to most animal learning protocols. We use elementary information theory to define contingency in such a way as to make it a measurable property of almost any conditioning protocol. We discuss how making it a measurable construct enables the exploration of the role of different contingencies in the acquisition and performance of classically and operantly conditioned behavior

Clinical emergency care research in low-income and middle-income countries: Opportunities and challenges

Disease processes that frequently require emergency care constitute approximately 50% of the total disease burden in low-income and middle-income countries (LMICs). Many LMICs continue to deal with emergencies caused by communicable disease states such as pneumonia, diarrhoea, malaria and meningitis, while also experiencing a marked increase in non-communicable diseases, such as cardiovascular diseases, diabetes mellitus and trauma. For many of these states, emergency care interventions have been developed through research in high-income countries (HICs) and advances in care have been achieved. However, in LMICs, clinical research, especially interventional trials, in emergency care are rare. Furthermore, there exists minimal research on the emergency management of diseases, which are rarely encountered in HICs but impact the majority of LMIC populations. This paper explores challenges in conducting clinical research in patients with emergency conditions in LMICs, identifies examples of successful clinical research and highlights the system, individual and study design characteristics that made such research possible in LMICs. Derived from the available literature, a focused list of high impact research considerations are put forth

Protocol for fast scRNA-seq raw data processing using scKB and non-arbitrary quality control with COPILOT

We describe a protocol to perform fast and non-arbitrary quality control of single-cell RNA sequencing (scRNA-seq) raw data using scKB and COPILOT. scKB is a wrapper script of kallisto and bustools for accelerated alignment and transcript count matrix generation, which runs significantly faster than the popular tool Cell Ranger. COPILOT then offers non-arbitrary background noise removal by comparing distributions of low-quality and high-quality cells. Together, this protocol streamlines the processing workflow and provides an easy entry for new scRNA-seq users. For complete details on the use and execution of this protocol, please refer to Shahan et al. (2022)

Prediction of fatigue life of aluminum 2024-T3 at low temperature by finite element analysis

The change in material properties at low temperature has always been one of the concerned design factors in aircraft industries. The wings and fuselage are repeatedly exposed to sub zero temperature during cruising at high altitude. In this study, fatigue tests were conducted on standard flat specimens of aluminum 2024-T3 at room temperature and at -30 °C. The monotonic and cyclic loading tests were conducted using MTS 810 servo hydraulic machine equipped with a cooling chamber. The monotonic tests were conducted at a crosshead speed rate of 1 mm/min and the cyclic tests at a frequency of 10 Hz with a load ratio of 0.1. The experimental data obtained, such as the yield strength, ultimate strength and S-N curve were used as the input parameters in ANSYS Workbench 16.1. This close agreement demonstrates that the isotropic model in ANSYS workbench is essential in predicting fatigue life. The increase in stress parameter causes fatigue life to decrease. Besides, the decrease in temperature causes the total fatigue life to increase