Abstract: A telephone control unit 12 allows the calling party to optionally select either a standard telephone call or a voice-mail transmission. If a voice-mail message is selected, the system allows the user to dictate the message which is then analog-to-digital converted and stored in memory. Once the user selects the receiving party's telephone number, the system dials the number and sends a header signal to the receiving unit indicating that a voice-mail transmission is desired. If the receiving unit detects the voice-mail header, it sends an acknowledgment signal, whereby the transmitting unit digitally compresses the stored voice-mail message and transmits the compressed message through the telephone network to the receiving site. The receiving site then flashes an indicator to the user that voice-mail is waiting. Upon a user replaying a voice-mail signal, the receiving site decompresses and digital to analog converts the signal for reproduction by the user.

Abstract: This invention relates to radio communication networks and more particularly, but not exclusively, to radio communication networks using multiple access techniques. A system and method for adaptively changing the characteristics of a signal transmitted across the network is provided. In one embodiment, the communications network includes at least two transceivers; wherein at least one of the transceivers is capable of sending a feedback signal to the other transceiver after receiving a signal transmitted over the network from the other transceiver after analysis of the transmitted signal and in the event that the signal characteristics of the system need to be varied.

Abstract: This invention relates to duplex and to half duplex transmission schemes and more particularly to the application of such schemes in TDMA and other multiple access environments. In accordance with a first aspect of the invention, there is provided a method of multiplexing signals transmitted by a number of terminals onto a communications link; the link having a capacity less than the total capacity of the terminals; the method including the step of varying the rate of encoding of said signals transmitted by said terminals whereby the bandwidth o the transmitted signals corresponds to the portions allocated to the terminals. In accordance with another aspect of the invention, there is provided a system for the communication of signals in real time over a channel; said system adapted to vary the bandwidth of at least one signal such that the number of signals multiplexed onto said channel can be dynamically varied.

Abstract: This invention relates to radio communications and in particular relates to a method for allocating channels in a radio communications system having a plurality of bearers in a system which is subject to slow temporal fading. In radio communications, signals are transmitted at a particular frequency, in a frequency band or in a number of frequency bands. Obstacles in a signal path, such as buildings in built-up areas and hills in rural areas, act as signal scatterers and these, together with fading, amongst other factors can cause signalling problems whereby signals may not be communicated on certain channel The present invention provides a system and method for channel allocation method for a multi-bearer communications network, with each bearer supporting a number of channels, wherein after allocation of a channel responsive to an access request from the available bearers which can provide access, the maximum number of available slots are left on each bearer, for a particular level of subscription.

Abstract: The invention concerns acid derivatives of formula IR.sup.1 --CON(R.sup.2)--N(R.sup.3)CO--X.sup.1 --Q--X.sup.2 --Gand pharmaceutically acceptable metabolically labile esters or amides thereof, and pharmaceutically acceptable salts thereof, in which R.sup.1, R.sup.2, R.sup.3, X.sup.1, Q, X.sup.2 and G have the meanings given in the specification. The invention also concerns processes for the preparation of the acid derivatives of formula I, pharmaceutical compositions containing them and their use as inhibitors of the binding of fibrinogen to glycoprotein IIb/IIIa.

Abstract: A bridge device (4) for connecting a plurality of communication networks (1-3) around which data is transmitted in frames which include control information defining at least the identity of a destination for data in the frame, each network having at least one end station (8-12). The bridge device comprises a corresponding plurality of data coupling units (13,14) for connection to respective ones of the networks (1-3), each data coupling unit including receive (13) and transmit (14) interfaces for respectively receiving data from and transmitting data onto the connected network. A common store (17) is connected to all the data coupling units for receiving data being transmitted from one network to another.

Abstract: The invention concerns acid derivatives of formula IR.sup.1 --CON(R.sup.2)--N(R.sup.3)CO--X.sup.1 --Q--X.sup.2 --G(I)and pharmaceutically acceptable metabolically labile esters or amides thereof, and pharmaceutically acceptable salts thereof, in which R.sup.1, R.sup.2, R.sup.3, X.sup.1, Q, X.sup.2 and G have the meanings given in the specification. The invention also concerns processes for the preparation of the acid derivatives of formula I, pharmaceutical compositions containing them their use as inhibitors of the binding of fibrinogen to glycoprotein IIb/IIIa.

Abstract: Compounds of formula I ##STR1## and metabolically labile esters and amides thereof, and pharmaceutically acceptable salts thereof, in which R.sup.13, M.sup.2, X.sup.1, Z.sup.1, Z.sup.1a, X.sup.2 and A.sup.1 have the meanings given in the specification. The compounds are useful as inhibitors of the binding of fibrinogen to glycoprotein IIb/IIIa. Novel intermediates are also disclosed.

Abstract: Compounds of formula I ##STR1## and metabolically labile esters and amides thereof, and pharmaceutically acceptable salts thereof, in which R.sup.13, M.sup.2, X.sup.1, Z.sup.1, Z.sup.1a, X.sup.2 and A.sup.1 have the meanings given in the specification. The compounds are useful as inhibitors of the binding of fibrinogen to glycoprotein IIb/IIIa. Novel intermediates are also disclosed.

Abstract: The disclosure relates to xanthene derivatives which possess analgesic activity, to processes for the manufacture of said derivatives and to pharmaceutical compositions containing them. Typical of the xanthene derivatives disclosed is 6-chloro-4-hydroxy-1'-methylxanthene-9-spiro-4'-piperidine.