Abstract: A high voltage propellant isolator includes at least two different types of isolator rings or segments, in alternating lateral arrangement, that direct the flow of propellant, such as xenon gas, in a tortuous path through the isolator.

Abstract: A high voltage propellant isolator includes at least two different types of isolator rings or segments, in alternating lateral arrangement, that direct the flow of propellant, such as xenon gas, in a tortuous path through the isolator.

Abstract: A high voltage propellant isolator includes at least two different types of isolator rings or segments, in alternating lateral arrangement, that direct the flow of propellant, such as xenon gas, in a tortuous path through the isolator.

Abstract: A high voltage propellant isolator includes at least two different types of isolator rings or segments, in alternating lateral arrangement, that direct the flow of propellant, such as xenon gas, in a tortuous path through the isolator.

Abstract: A high voltage propellant isolator includes at least two different types of isolator rings or segments, in alternating lateral arrangement, that direct the flow of propellant, such as xenon gas, in a tortuous path through the isolator.

Abstract: The invention provides a lipid of general formula (I) or (II): wherein X1, X2 and R1 to R5 are as defined herein. Such lipids are used to form complexes with a biologically-active material such as a nucleic acid, peptide or small molecule for delivering the biologically-active material to cells. The complexes may incorporate an integrin-binding peptide and, when the biologically-active material is DNA, thereby constitute a LID complex.

Abstract: A complex that comprises (i) a nucleic acid, (ii) an integrin-binding component, for example, an intergrin-binding peptide, (iii) a polycationic nucleic acid-binding component, for example, oligolysine, and (iv) a lipid component, for example, a cationic liposome, has transfection activity.

Abstract: A complex that comprises (i) a nucleic acid, (ii) an integrin-binding component, for example, an integrin-binding peptide, (iii) a polycationic nucleic acid-binding component, for example, oligolysine, and (iv) a lipid component, for example, a cationic liposome, has transfection activity.

Abstract: A complex that comprises (i) a nucleic acid, (ii) an integrin-binding component, for example, an integrin-binding peptide, (iii) a polycationic nucleic acid-binding component, for example, oligolysine, and (iv) a lipid component, for example, a cationic liposome, has transfection activity.

Abstract: Composition comprising DNA associated with a polycation moiety wherein the polycation moiety is itself coupled to an integrin receptor binding moiety is disclosed. Preferably, the integrin receptor binding moiety is a peptide, and the compositions can be used to deliver DNA to a cell where it will be expressed, for example, to treat a condition by gene therapy. In a preferred embodiment, the integrin receptor binding moiety comprises a peptide, in particular a cyclic peptide, comprising the sequence RGD. In a particularly preferred embodiment, the peptide comprises the sequence GGCRGDMFGC. Cyclic configuration in this sequence is imposed by virtue of the presence of two cysteine residues which can form a disulphide bond.

Abstract: A coupled cavity traveling tube employs a number of adjacent stacked annular magnetic coils (52a-52l) of insulated copper tape mounted on a housing (40) that contains an electron beam path (22) surrounded by a coupled cavity circuit (42,44). An electron beam that is focused by the annular magnetic coils is projected by an electron gun (10) at one end of the traveling wave tube to a collector (26) at the other end of the electron beam path. RF input and output ports (48,50) are coupled to opposite ends of the coupled cavity circuit, with the entire assembly mounted in an outermost device housing (12,28,36) that is sealed to and around the externally projecting RF input and output ports by a pair of sealing rings (60,62) that circumscribe coils (52b,52c,52l) at opposite ends of the traveling wave tube. Hot melt plastic (58a-58i) is injected into spaces between adjacent ones of the annular coils to firmly position the stack of coils against shock and vibration.

Abstract: An end portion (14a) of a center conductor (14) of a coaxial cable (16) protrudes transversely into a tubular waveguide (10) near an end thereof. A piston (22) having a stepped inner wall (24) closes the end of the waveguide (10). The inner wall (24) is formed with two or more steps (24a,24b,24c) which protrude axially into the waveguide (10) by different distances (L1,L2,L3), reducing the return loss and extending the bandwidth of the coaxial cable-to-waveguide transition.

Abstract: A buffer is provided for protecting the electron beam collector of a traveling wave tube. The collector comprises an elongated tubular wall, an elongated tubular insulating wall of one type of material, an elongated cylindrical electrode of another type of material coaxially positioned within the insulating wall, and the buffer interposed between the electrode and the insulating wall. The buffer comprises a continuous web of buffer material capable of being bonded to dissimilar insulating wall material and electrode material. The web having an alternating pattern of corrugations, the vertices of the corrugations are generally planar which define two generally parallel, planar surfaces which in turn are adapted for bonding to the insulating wall and the electrode.