I admit I only skimmed this, but it looks like they're taking advantage of colligative properties to induce the phase change... but in order to do that, they're causing ions to "flow" into a solid material so that it melts into a liquid.

I wonder how they make that happen; how, exactly, can they cause ions to flow into a solid?

[Not skeptical (necessarily), just curious]

“While the longitudinal associations in our study are compelling, the design of the study did not allow us to demonstrate a cause-and-effect relationship,” Braley explained. “Additional prospective work that includes information on strength of the human-animal bond and its effect on cognitive trajectories, and incorporates study of biological mechanisms that could mediate this relationship, are still needed.” (Braley is Tiffany J. Braley--one of the authors.)

This can be an interesting finding and a prompt for further research, but I absolutely agree with a caution about turning correlation into causation. The burden of proof should be on the affirmative.

Also, it's difficult to have a well-informed debate because the link is to an article about the paper--not the paper itself.

I absolutely agree that the effort (and unfortunately the responsibility) for contraception is disproportionately assigned to women. I think many people dislike the loss of sensation condoms cause, but there are other issues; you have to have them with you, they can be expensive, their availability in certain areas can be inconsistent, some people (especially younger people, I imagine) are embarrassed to buy them, they can fit poorly, slip off, break, etc.

Hormonal contraception is "easier" in many ways.

I also want to note that I'm not ignoring STI prevention--that's just a different topic.