Hippocampus’s role in forming “task-related” associations: Flashing to the things you are looking for

Eichenbaum and colleagues observed that the same place did or did not activate the "goal-approach" cells in hippocampus depending on whether the place was the way for rats to approach specific goal. Parallel with this, the present neuroimage study revealed that, the same type of items could activate the hippocampus more when it was related to the task at hand than when it not. Participants were scanned by fMRI while they made judgments on the type of relationships contained in the word-pairs (e.g., Does the word pair, "furniture-table", contain a "category-exemplar" relationship?). Event-related analysis revealed that the forming of "task-related" association activated hippocampus more than that of "task-unrelated", even if it was the same type of items, and, this hippocampal difference was not caused by the different judgment requirements, nor by the effects of "yes" response. Consistently, the post-judgment cued-recall test exhibited a better retrieval performance for "task-related" associations than for the same type but "task-unrelated" associations. Results also showed that, the semantic re- latedness between the to-be-associated individual words (e.g., the related word pair "healthy-hospital" versus the unrelated word pair "price-way") was not enough to activate the hippocampus when it was "task-unrelated". Generally, we proposed that, through participating in forming of "task-related" asso- ciations and consolidating of episodic memory, hippocampus enabled the organism to keep the in- formation that owned great survival values in mind for future usage.

Fluidization science,its development and future

By revisiting the three stage theory for the progress of science proposed by Taketani in 1942, the footmarks of fluidization research are examined. The bubbling and fast fluidization issues were emphasized so that the future offluidization research can be discussed among scientists and engineers in a wider perspective. The first cycle of fluidization research was started in the early 1940s by an initial stage of phenomenology. The second stage of structural studies was kicked off in the early 1950s with the introduction of the two phase theory. The third stage of essential studies occurred in the early 1960s in the form of bubble hydrodynamics. The second cycle, which confirmed the aforementioned three stages closed at the turn of the century, established a general understanding of suspension structures including agglomerating fluidization, bubbling, turbulent and fast fluidizations and pneumatic transport; also established powerful measurement and numerical simulation tools.After a general remark on science, technology and society issues the interactions between fluidization technology and science are revisited. Our future directions are discussed including the tasks in the third cycle, particularly in its phenomenology stage where strong motivation and intention are always necessary, in relation also to the green reforming of the present technology. A generalized definition of ＇fluidization＇ is proposed to extend fluidization principle into much wider scientific fields, which would be effective also for wider collaborations.