Can I still save my lucky bamboo?

[super_simple]

My little lucky bamboo that I have had for just over a year is dying. A couple of months ago one of the leaves had a growth spurt, but the new growth was a pale whitish green, not the bright green of the other leaves. A couple of weeks ago I noticed that this leaf was turning a little bit yellow. This worsened and now all of the leaves are turning brownish. The stalk is fine, but there aren't that many roots (my lucky bamboo has never had very many roots). It's condition is getting worse every day, and I don't know how much longer it will be alive for.
I don't know what's wrong with it. I have kept it near a window that is usually open in the summer, and I think the cool fall weather could have done some damage to it. (I have moved it to a different location) It's also been recently put in a new container that is bigger. I don't fertilize my lucky bamboo because I don't know exactly what to use for it. Could this be the problem?

I'd really appreciate some help, my lucky bamboo was given to me last summer and it has sentimental value (not to mention the fact that I love it because it's lasted over a year without dying on me--I'm not great with plants.) I hope it's not to late.
Thank you!

My lucky bamboo several months ago:


My lucky bamboo today: