scholarly journals Detonation Energy Densities from the Cylinder Test

2015 ◽  
Author(s):  
P C Souers ◽  
P A Vitello
Keyword(s):  
Cylinder Test ◽  
Detonation Energy

Ascorbic acid improves extrapyramidal syndromes and corpus striatal degeneration induced by dopamine-2 receptor inhibition in Wistar rats

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Sirajo U. Mujittapha ◽  
Murtala Kauthar ◽  
Ishola O. Azeez ◽  
John C. Oyem
Keyword(s):  
Ascorbic Acid ◽  
Normal Saline ◽  
Wistar Rats ◽  
Corpus Striatum ◽  
Extrapyramidal Symptoms ◽  
Motor Deficit ◽  
Cylinder Test ◽  
Extrapyramidal Syndromes ◽  
Dopamine 2 Receptor ◽  
Inhibition Group

AbstractObjectivesThe prolonged uses of fourth-generation antipsychotics have been implicated in inducing extrapyramidal syndromes characterized by the motor deficit. This was attributed to the loss of dopamine-2 receptor (D2R) signaling. However, ascorbic acid (SVCT2R stimulation) in the brain is proposed to modulate D2R activity. We, therefore, investigated the beneficial roles of ascorbic acid in improving the extrapyramidal symptoms seen in D2R loss.MethodsTwenty adult male Wistar rats of average weight 200 g were distributed randomly into four groups. The control (NS) received normal saline for 28 days, Untreated D2R inhibition group (−D2R) received normal saline for seven days and then subsequently received chlorpromazine for 21 days, D2R inhibition group treated with ascorbic acid (−D2R+SVCT2R) received chlorpromazine for 21 days and was subsequently treated with ascorbate for seven days while the withdrawal group (WG) received chlorpromazine for 21 days and subsequently received normal saline for seven days. Motor deficits were assessed using a rotarod and cylinder test. The corpus striatum was harvested, processed, and stained using H&E and Nissl stains. Cellular density was analyzed using Image J software 1.8.0.ResultsMotor deficit was observed in −D2R animals administered chlorpromazine with less improvement in WG compared to control (p<0.05) in both rotarod and cylinder test. Ascorbic acid (SVCT2R stimulation) significantly (p<0.001) improved the latency of fall and climbing attempts observed in −D2R animals. The density of basophilic trigoid bodies was significantly (p<0.001) restored in −D2R+SVCT2R group, suggesting recovery of neural activity in the corpus striatum. Moreover, the hallmarks of neuronal degeneration were less expressed in the ascorbic acid treatment groups.ConclusionsAscorbic acid putatively ameliorates extrapyramidal symptoms observed in D2R blockage by chlorpromazine in Wistar rats.

A Transient Single Cylinder Test System for Engine Research and Control Development

2005 ◽  
Author(s):  
John L. Lahti ◽  
Matthew W. Snyder ◽  
John J. Moskwa
Keyword(s):  
Test System ◽  
Intake Manifold ◽  
Test Accuracy ◽  
Test Configuration ◽  
Single Cylinder ◽  
Cylinder Test ◽  
Single Cylinder Engine ◽  
Wide Range ◽  
Reduce Development Time ◽  
High Bandwidth

A transient test system was developed for a single cylinder research engine that greatly improves test accuracy by allowing the single cylinder to operate as though it were part of a multi-cylinder engine. The system contains two unique test components: a high bandwidth transient hydrostatic dynamometer, and an intake airflow simulator. The high bandwidth dynamometer is used to produce a speed trajectory for the single cylinder engine that is equivalent to that produced by a multi-cylinder engine. The dynamometer has high torque capacity and low inertia allowing it to simulate the speed ripple of a multi-cylinder engine while the single cylinder engine is firing. Hardware in loop models of the drivetrain and other components can be used to test the engine as though it were part of a complete vehicle, allowing standardized emissions tests to be run. The intake airflow simulator is a specialized intake manifold that uses solenoid air valves and a vacuum pump to draw air from the manifold plenum in a manner that simulates flow to other engine cylinders, which are not present in the single cylinder test configuration. By regulating this flow from the intake manifold, the pressure in the manifold and the flow through the induction system are nearly identical to that of the multi-cylinder application. The intake airflow simulator allows the intake runner wave dynamics to be more representative of the intended multi-cylinder application because the appropriate pressure trajectory is maintained in the intake manifold plenum throughout the engine cycle. The system is ideally suited for engine control development because an actual engine cylinder is used along with a test system capable of generating a wide range of transient test conditions. The ability to perform transient tests with a single cylinder engine may open up new areas of research exploring combustion and flow under transient conditions. The system can also be used for testing the engine under conditions such as cylinder deactivation, fuel cut-off, and engine restart. The improved rotational dynamics and improved intake manifold dynamics of the test system allow the single cylinder engine to be used for control development and emissions testing early in the engine development process. This can reduce development time and cost because it allows hardware problems to be identified before building more expensive multi-cylinder engines.

A Computational Investigation of Piston Bowl Geometry for a Large Bore Two-Cycle Diesel Engine

2011 ◽  
Author(s):  
Jonathan Dolak ◽  
Deep Bandyopadhyay
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Simulation Software ◽  
Spray Angle ◽  
Tier 2 ◽  
Piston Bowl ◽  
Cylinder Test ◽  
Advanced Combustion ◽  
Combustion Simulation ◽  
Reduce Emissions

The objective of this research was to optimize an Electro-Motive Diesel (EMD) large-bore, two-cycle diesel engine (710 cubic inches of displacement per cylinder) at high load to minimize soot, nitrogen oxide (NOx) and fuel consumption. The variables considered were the number of spray-hole nozzles per injector, including spray angle and piston bowl geometry, for a range of injection pressures. Analytical simulations were conducted for a calibrated EMD 710 Tier 2 engine and a few of the top-performing cases were studied in detail. CONVERGE™, a commercially available, advanced combustion simulation software was used in this analysis. A surface deforming tool, Sculptor®, was used to obtain various piston bowl geometries. MiniTab® was utilized for statistical analysis. Results show that optimal combinations of injection variables and piston bowl shape exist to simultaneously reduce emissions and fuel consumption compared to Tier 2 EMD 710 engines. These configurations will be further tested in a single-cylinder test cell and presented later. This investigation shows the importance of bowl geometry and spray targeting on emissions and fuel consumption for large-bore, two-stroke engines with high power density.

Abstract T P238: Microglial CX3CR1 Required for M2 Polarization and Recovery After Intracerebral Hemorrhage

Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
Roslyn A Taylor ◽  
Matthew D Hammond ◽  
Youxi Ai ◽  
Lauren H Sansing
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
Intracerebral Hemorrhage ◽  
Gait Analysis ◽  
Functional Outcome ◽  
Cylinder Test ◽  
M2 Microglia ◽  
Inflammatory Phenotype ◽  
Peripheral Leukocytes ◽  
The Right

Introduction: Intracerebral hemorrhage (ICH) results in the activation of microglia, the resident immune cells of the central nervous system. Microglia may polarize into an M1, pro-inflammatory phenotype, or an M2 phenotype associated with repair. CX3CR1 is a chemokine receptor on microglia and monocyte subsets. CX3CR1-null microglia have been shown to have dysregulated inflammation. We hypothesize that CX3CR1-null microglia have a prolonged M1 phenotype, contributing to worse functional outcome after ICH. Methods: ICH was modeled by injection of 20μl of blood into the right striatum. Neurological deficit was quantified using digital gait analysis, cylinder test, and beam walking. Mice were sacrificed 14 days after ICH; brains were harvested for flow cytometry and immunohistochemistry (IHC). C57BL/6 (WT) and CX3CR1 GFP/GFP (CX3CR1-null) mice were irradiated and reconstituted with bone marrow from WT mice carrying the congenic marker CD45.1 to generate bone marrow chimeras (CD45.1WT or CD45.1CX3CR1-null). M1 microglia were identified as expressing MHCII and M2 microglia with CD206. Results: The CD45.1CX3CR1-null mice show worse functional outcome 14 days after ICH by cylinder test (p=0.002), beam walking (p=<0.001) and gait analysis (p=0.02). By flow cytometry, few peripheral leukocytes remain in the brain at 14 days, indicating that F4/80 + and CD11b + cells visualized by IHC are likely microglia, not peripheral macrophages. By IHC, CD45.1 CX3CR1-null mice have significantly more amoeboid F4/80 + MHCII + cells per field (M1 microglia) than CD45.1WT mice (p=0.02). CD45.1 CX3CR1-null mice have significantly fewer CD11b + CD206 + cells per field (M2 microglia) compared to CD45.1WT mice (p=0.04). Conclusions: Our results suggest microglial CX3CR1 signaling is necessary for microglia to transition from M1 to M2 and contribute to recovery after ICH.

Reliability of behavioral tests in the middle cerebral artery occlusion model of rat

2018 ◽  
Vol 53 (5) ◽  
pp. 478-490 ◽  
Author(s):  
Junghoon Yu ◽  
Jinkyoo Moon ◽  
Joonyoung Jang ◽  
Jee In Choi ◽  
Jooeun Jung ◽  
...  
Keyword(s):  
Middle Cerebral Artery ◽  
Middle Cerebral Artery Occlusion ◽  
Cerebral Artery ◽  
Rat Model ◽  
Artery Occlusion ◽  
Behavioral Tests ◽  
Walking Test ◽  
Satisfactory Level ◽  
Cylinder Test ◽  
Cerebral Artery Occlusion

Stroke is one of the leading causes of death and disability worldwide, and its incidence is increasing. To overcome impairment from stroke, translational research for developing new therapeutic technologies has been conducted and middle cerebral artery occlusion (MCAo) in rat is the representative model. Since recovery from neurological impairment in contralateral limbs caused by brain damage is the major goal of treatment, behavioral tests that assess the relevant function are used. To determine therapeutic effect, obtaining reliable results of behavioral assessment is a prerequisite. However, studies on the reliability of behavioral tests in the MCAo rat model and necessity of prior training have not yet been reported. In this study, the authors investigate relative and absolute inter-rater reliabilities of modified neurological severity score (mNSS), cylinder test, and grid-walking test before training and repeated training every week until the reliability of results reached a satisfactory level. The training included repeated learning of the scoring system and decreasing disagreements among the raters. For MCAo modeling, adult male Sprague-Dawley rats were subjected to 90 min of transient MCAo. Six raters conducted behavioral tests via observation of video-recording on sham-operated and MCAo model rats at 3 or 7 days after the intervention. An independent experimenter randomly numbered each video clip to blind the experiment. The results of reliabilities were unacceptable before training and improved to a satisfactory level after 6 weeks of training in all of the tests. In conclusion, mNSS, cylinder test, and grid-walking test on the MCAo rat model are reliable evaluation methods after conducting appropriate training.

scholarly journals Adherence between steel bars and lightweight concrete with EPS beads

2017 ◽  
Vol 10 (1) ◽  
pp. 122-140
Author(s):  
A. L. SARTORI ◽  
L. M. PINHEIRO ◽  
R. M. DA SILVA ◽  
S. B. FREITAS ◽  
T. G. CESAR
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Mechanical Characteristics ◽  
Lightweight Concrete ◽  
Monotonic Loading ◽  
Adherence Behavior ◽  
Ordinary Concrete ◽  
Cylinder Test ◽  
Pull Out ◽  
Steel Bars

Abstract This paper describes the adherence behavior of a structural lightweight concrete with EPS beads (SLCEB) in a monotonic loading, based in a bibliographic review and in pull-out tests. The results of these SLCEB tests were compared with those of an ordinary concrete (OC) and with the values based in indications of the Brazilian code ABNT NBR 6118:2014 - Design of concrete structures. The pull-out tests of two batches of SLCEB and one of OC were analyzed, in a total of 60 tests. Mechanical characteristics were determined too, such as: compressive strength and tensile strength in split cylinder test. The calculated results according to the above mentioned standard were very different from those obtained in the tests, indicating that the theoretical values are more conservative than the experimental ones. It was also verified that it is possible to use SLCEB in structures with respect to the adequate adherence of reinforcement in the concrete.

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