Abstract: A method and system is for receiving data representing gene clusters, the gene clusters including one or more genes configured to encode one or more polypeptides or other small molecules; accessing a machine learning model, the machine learning model being trained with a training dataset that associates the gene clusters to structures of one or more small molecules represented in the data; applying the machine learning model to the data representing the gene clusters; identifying, based on applying the machine learning model, one or more monomers associated with at least one gene cluster represented in the data; and determining a structure for a natural product including the one or more monomers.

Abstract: A method and system is for searching a database to identify structures of molecular compounds from mass spectrometry data. Operations of the method and system include receiving a query for a target molecular structure in the database, the query representing a query spectrum; accessing a machine learning model trained with molecule-spectrum pairs; inputting the query spectrum into the machine learning model; generating, from the machine learning model, a score for each of one or more molecular structures, each score representing a probability that a molecular structure corresponds to the query spectrum; selecting, based on each of the scores, a small molecule; and outputting, on a user interface, a representation of the small molecule.

Abstract: Two stages of PPP negotiations are adopted for users to access a virtual private network (VPN). The access concentrator for providing PPP connections is designed to provide the two-stage connection. In the first stage, a user is verified as an authenticated VPN user, and a first network address is assigned. In the second stage, a service requested by the authenticated user is decoded for determining either the service being a VPN service or a non-VPN service. If the service is a non-VPN service, the request is processed by reference to the network address. Otherwise, a second PPP negotiation is executed between the access concentrator and a server in a VPN, and then the server of the VPN assigns the user a VPN address for providing VPN service.