Subsynchronous Shaft Vibration in an Integrally Geared Expander-Compressor due to Vortex Flow in an Expander

LecturesSubsynchronous shaft vibration was observed in an integrally geared expander-compressor when the machine was operated with a partial load in the course of plant start up. The root cause of the synchronous shaft vibration was identified, by means of CFD analysis, as the vortex flow which was generated in the downstream piping of the gas expander wheel. OEM installed an object, called “vortex breaker”, in the piping in order to eliminate the excitation force of the vortex flow, and as the result, the subsynchronous shaft vibration disappeared. This paper provides the detailed shaft vibration data, root cause analysis, countermeasure and the result from the countermeasure

Comprehensive behavioral phenotyping of a new Semaphorin 3 F mutant mouse

Background: Semaphorin 3 F (Sema3F) is a secreted type of the Semaphorin family of axon guidance molecules. Sema3F and its receptor neuropilin-2 (Npn-2) are expressed in a mutually exclusive manner in the embryonic mouse brain regions including olfactory bulb, hippocampus, and cerebral cortex. Sema3F is thought to have physiological functions in the formation of neuronal circuitry and its refinement. However, functional roles of Sema3F in the brain remain to be clarified. Here, we examined behavioral effects of Sema3F deficiency through a comprehensive behavioral test battery in Sema3F knockout (KO) male mice to understand the possible functions of Sema3F in the brain. Results: Male Sema3F KO and wild-type (WT) control mice were subjected to a battery of behavioral tests, including neurological screen, rotarod, hot plate, prepulse inhibition, light/dark transition, open field, elevated plus maze, social interaction, Porsolt forced swim, tail suspension, Barnes maze, and fear conditioning tests. In the open field test, Sema3F KO mice traveled shorter distance and spent less time in the center of the field than WT controls during the early testing period. In the light/dark transition test, Sema3F KO mice also exhibited decreased distance traveled, fewer number of transitions, and longer latency to enter the light chamber compared with WT mice. In addition, Sema3F KO mice traveled shorter distance than WT mice in the elevated plus maze test, although there were no differences between genotypes in open arm entries and time spent in open arms. Similarly, Sema3F KO mice showed decreased distance traveled in the social interaction test. Sema3F KO mice displayed reduced immobility in the Porsolt forced swim test whereas there was no difference in immobility between genotypes in the tail suspension test. In the fear conditioning test, Sema3F KO mice exhibited increased freezing behavior when exposed to a conditioning context and an altered context in absence of a conditioned stimulus. In the tests for assessing motor function, pain sensitivity, startle response to an acoustic stimulus, sensorimotor gating, or spatial reference memory, there were no significant behavioral differences between Sema3F KO and WT mice. Conclusions: These results suggest that Sema3F deficiency induces decreased locomotor activity and possibly abnormal anxiety-related behaviors and also enhances contextual memory and generalized fear in mice. Thus, our findings suggest that Sema3F plays important roles in the development of neuronal circuitry underlying the regulation of some aspects of anxiety and fear responses

Subsynchronous Shaft Vibration in an Integrally Geared Expander-Compressor due to Vortex Flow in an Expander

LecturesSubsynchronous shaft vibration was observed in an integrally geared expander-compressor when the machine was operated with a partial load in the course of plant start up. The root cause of the synchronous shaft vibration was identified, by means of CFD analysis, as the vortex flow which was generated in the downstream piping of the gas expander wheel. OEM installed an object, called “vortex breaker”, in the piping in order to eliminate the excitation force of the vortex flow, and as the result, the subsynchronous shaft vibration disappeared. This paper provides the detailed shaft vibration data, root cause analysis, countermeasure and the result from the countermeasure

Circadian Gene Circuitry Predicts Hyperactive Behavior in a Mood Disorder Mouse Model

SummaryBipolar disorder, also known as manic-depressive illness, causes swings in mood and activity levels at irregular intervals. Such changes are difficult to predict, and their molecular basis remains unknown. Here, we use infradian (longer than a day) cyclic activity levels in αCaMKII (Camk2a) mutant mice as a proxy for such mood-associated changes. We report that gene-expression patterns in the hippocampal dentate gyrus could retrospectively predict whether the mice were in a state of high or low locomotor activity (LA). Expression of a subset of circadian genes, as well as levels of cAMP and pCREB, possible upstream regulators of circadian genes, were correlated with LA states, suggesting that the intrinsic molecular circuitry changes concomitant with infradian oscillatory LA. Taken together, these findings shed light onto the molecular basis of how irregular biological rhythms and behavior are controlled by the brain

キナ植物体内に生息するエンドファイト糸状菌もキナアルカロイドを産生する(発表論文抄録(2011))

We report that the endophytic filamentous fungus Diaporthe sp., isolated from Cinchona ledgeriana and cultivated in a synthetic liquid medium, produces Cinchona alkaloids (quinine, quinidine, cinchonidine, and cinchonine). This shows that Cinchona alkaloids are produced not only in Cinchona plant cells, but also in endophytic microbe cells.We report that the endophytic filamentous fungus Diaporthe sp., isolated from Cinchona ledgeriana and cultivated in a synthetic liquid medium, produces Cinchona alkaloids (quinine, quinidine, cinchonidine, and cinchonine). This shows that Cinchona alkaloids are produced not only in Cinchona plant cells, but also in endophytic microbe cells