Abstract: The present invention relates to an isolated peptide consisting of a sequence of 3 to 39 amino acids derived from the amino acid sequence SEQ ID NO: 1, said peptide having a sequence of amino acids selected from the group consisting of: a) sequences of 3 to 39 amino acids comprising at least the residues 6 to 8 of SEQ ID NO: 1, and b) sequences of 3 to 39 amino acids having at least 70% identity with said sequence in a).

Abstract: An adapter No (n-1) propagates a daisy-chained grant signal directly to the adapter No (n) and a by-passed grant signal to the adapter No (n+1) case. The adapter No (n) is responsive to the status of the previous adapter in the chain, for determining which of the regular grant signal ("GR") or by-passed grant signal ("GRA") has to be taken account of by the succeeding adapter, when the latter wants to access the transmission bus (11). Further, the adapters connected to the chain may be partitioned into groups (80) within which the grant signal is distributed in parallel to the adapters, and propagated to the next group only when none of its adapters (10) requests access to the transmission bus. The same priority level is given to each adapter or group of adapters connected to the daisy-chain, and permits said chain to remain operative even when several adapters are unplugged or malfunction.

Abstract: An interface mechanism is described for controlling the exchange of information between two devices, such as a direct memory access controller 12 and adapter 5 through bus 10. The exchange is initiated by the adapter which activates the request line 44 and read/write signal on line 62 indicating whether a memory read or write operation is requested. The controller sends back a grant signal on line 46 when the request may be serviced. Ready line 60 is monitored and checked by the adapter and valid line 52 is monitored and checked by the controller. Turn around signal on line 64 controls the direction of the transfer on bidirectional data lines 66. A write or read operation begins with the transmission by the adapter of control parameters (address and byte count). Then for a write operation, the data burst is sent from the adapter to the controller and for a read operation the data burst is sent from the controller to the adapter. The sampling clock always travels with the parameters and data.

Abstract: A catalytic composition is employed for the isomerization of paraffins and the alkylation of paraffins with olefins.The composition is constituted by a mixture of Lewis acid corresponding to the formula MXm where:M is an atom of a metal belonging to Groups IV, V and VI of the Periodic Table of Elements,X is a halogen,m is within the range of 3 to 6,And a sulphonic acid corresponding to the general formula RF(SO.sub.3 H)p where RF represents a perfluorinated alkyl or cycloalkyl hydrocarbon radical having a number of carbon atoms ranging from 2 to 8 and p is 1 or 2.

Abstract: The composition is constituted by a mixture of Lewis acid corresponding to the formula MXm where:M is an atom of a metal belonging to Groups IV, V and VI of the Periodic Table of Elements,X is a halogen,m is within the range of 3 to 6,And a sulphonic acid corresponding to the general formula RF(SO.sub.3 H)p where RF represents a perfluorinated alkyl or cycloalkyl hydrocarbon radical having a number of carbon atoms ranging from 2 to 8 and p is 1 or 2.