You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Cell biology: notch recycling is numbed. During asymmetric cell division, the Notch regulator Numb segregates unequally to establish different cell fates in the two daughter cells. Numb is thought to act as an endocytic protein. Two new studies show that Numb antagonizes Notch signaling by also regulating recycling of Sanpodo-Notch complexes via AP-1.
{"Chemical": []}