[Marc, Katsuki]

Thanks to Kanzawa-san we got the new pusher for the glass cell container.

We measured again birefringence versus pusher position. This time we saw small increase in ellipticity while it was strongly decreaseing with the plastic cell container.

One possibility is that the pusher pressure was inducing stress birefringence on the plastic walls.

We then measured mass versus pusher discplecements for both plastic and cell container with the 3d printed holder.

We still had some issue of hydrogel escaping from the space between the pusher and cell container walls so we then put the pusher into one finger of a plastic glove that mostly solved this issue.

We repeated measurement of hydrogel birefringence versus pusher position but this time the restoring force of hydrogel was stronger and pushing up the translation stage despite zip tie.

We should prepare a better enclosure for the translation stage.

I tried to apply large displacement while holding the translation stage but the glass cell container broke..

In any case it seems that hydrogel is sensitive enough to cell induced birefringence.

All measurements were done with 10% hydrogel mix.

All data and analysis are in 'hydrogel_birefringence.py' file