div class=ts-pagebutton class=gotoPage data-page=1Page 1button div class=ts-imageimg data-url=to-kill-or-not-to-killhtmlpage=1 data-page=1 class=ts-thumb lazyload alt=Page 1: To kill or not to kill loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAQAAADYv8WvAAAAD0lEQVR42mP8X8AwAgiABKBAv+vAXklAAAAAElFTkSuQmCC data-src=https:reader031vdocumentsmxreader031viewer2022020103575069171a28ab0f07b336a4html5thumbnails1jpg width=140 height=200 divp© 1998 Nature Publishing Group http:wwwnaturecomnsmbpdiv