The plasma pentraxin proteins serum amyloid P component (SAP) and C-reactive protein (CRP) bind specifically to nuclear autoantigens. There is a blunted acute phase response of human CRP in systemic lupus erythematosus (SLE), and of mouse SAP in NZB/W murine SLE. SAP deficiency in (129/Sv X C57BL/6)F2 mice is associated with spontaneous antinuclear autoimmunity. The pentraxins may thus function in preventing autoimmunity. Pure line C57BL/6 SAP knockout mice, studied here for the first time, spontaneously developed broad spectrum anti-nuclear autoimmunity resembling human SLE, and, females in particular had proliferative immune complex glomerulonephritis but without proteinuria or renal failure. Mice hemizygous for the SAP gene deletion had an intermediate autoimmune phenotype. Injected apoptotic cells and isolated chromatin were more immunogenic in SAP-/- than in wild-type mice. Extrinsic chromatin was catabolised predominantly in hepatocytes, Kupffer's cells and renal parenchymal cells. Plasma clearance of long chromatin and core particles was marginally slower in SAP-/- mice, with significantly greater splenic uptake of nucleosome core particles, which may have immunological significance. SAP bound to apoptotic cells but had no effect on their phagocytosis in mice in vivo, or by human macrophages in vitro. CRP also bound to apoptotic cells but did not compete with SAP, indicating recognition of different ligands. In contrast, to the C57BL/6 strain, pure line 129/Sv SAP knockout mice did not produce autoantibodies. Formation of antinuclear autoantibodies is thus markedly strain dependent. Interestingly, transgenic expression of human SAP in the C57BL/6 SAP knockouts did not abrogate the autoimmune phenotype. Transgenic reconstitution of the knockouts with mouse SAP is currently in progress to confirm that autoimmunity is caused by SAP deficiency and not by 129/Sv genes transferred into the C57BL/6 background during homologous recombination, or by disruption of loci associated with murine SLE that are close to the mouse SAP gene.

The Recent as represented on the Texas coast may be separated chronologically into the Ingleside, Alazan, and Post-Alazan or Present times. Each subdivision is associated with a major climatic fluctuation, the Ingleside and Post-Alazan with the “first and second climate optimums”, respectively, and the Alazan with the “Little Ice Age”. Characteristic of the Ingleside and Present times, and possibly of Alazan time, are the associated coastal barrier and lagoon systems. The physiographic features of the Present coastal barrier system forming the outer Texas coast, manifest a direct relation to the climatic characteristics of the Present, favoring onshore movement of sediments. The sediments carried by mainland streams to the bay systems, then moved through the barrier passes by tidal currents, and contributed to a southwestward moving longshore current. Wave transport and eddy action transfer the sediments to an inshore drift current, which is reversible in direction with the longshore component of the local wind. The direction of the inshore drift current affects directly the orientation of foreshore features: spits, bays between cusps, and the associated backwash channels and ripple marks. Three basic profiles representing calm, normal, and storm wind conditions result from secretion or removal of beach sediments. Hurricanes, occurring at any one locality on the Texas coast about once every 25 years, produce great waves that flood the barrier system in the region where the storm track crosses the coastline. A hurricane flood flattens low foredunes, breaks through gaps in higher foredunes, forms washover fans and temporary passes, and carries the material across the island channels, depositing the sediments in front of back dune fields and in the lagoon. The dry portion of the present wind regime (that free of precipitation) transports the Gulf beach sands inland over the barrier system. Precipitation, occurring more often with northerly winds than with southerly winds, reduces the effect of the former on sand movement. SE is the prevailing wind direction and also the resultant effective direction causing Aeolian movement of sand over the barrier system, producing an over-all resultant NW movement. Blowout tongues, barchans, and seif dunes of the barrier system, also the dune fields and wind-cut ridges and furrows of the mainland, have developed trends in agreement with the NW direction of Aeolian sand movement. The NW trends are superimposed on a sand sheet that centers at 27°N latitude on the mainland and extends W from Laguna Madre. The sand sheet was probably the product of a different wind regime because of its non-agreement with the present direction of sand movement. A gradual change of physiographic features southwestward along the coast is the direct result of the different degrees of sand movement corresponding with a climatic range from humid in the vicinity of Sabine Pass to semi-arid on northern Padre Island. Desert-type dunes, the seifs and barchans typical of the great ergs of the world, are found in the semi-arid portion of the Texas barrier system. Of the entire continental shores of the United States, only along the Texas shores do such dunes develop for no other shore in the United States approaches the same degree of aridity. / text

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Electrodeposited nickel-iron and nickel-zinc alloys have been studied using `direct' methods e. g. XRD, microscopy, EDX and GDOES on coatings having different thicknesses and deposited on different substrates. The work has confirmed and extended the ideas of Finch et al. (2, 51), Piontelli et al. (3) and Pangarov (49.120, 121) applicable to alloy deposition. It has shown that a better understanding, particularly of the initial deposition stages, can be obtained by considering crystallographic, energy and electrochemical aspects in combination rather than individually. Initially alloy is deposited on a `foreign' substrate but subsequently the growing alloy itself serves as the `substrate'. Similarly `old' crystallites have to compete for growth with `newly' nucleated ones as the deposit develops. The three stages of growth observed in nickel-iron and nickel-zinc are discussed. Crystallographic strain, resulting from mismatch between substrate and deposit structures and the presence of impurities, along with the energies required to produce different structures are considered to play a major role in determining structure during alloy deposition. Competition for discharge between hydrogen and metallic ions at the changing deposit surface, including changes in its electrochemical nature are considered. In addition possible effects resulting from adsorbed species, including co-discharged hydrogen as well as other species such as hydroxyl ions or precipitated hydroxides are discussed. Whereas during initial nucleation the original substrate is the dominating influence, in the later stages the electrolytic parameters determine the structure of the deposit. If the structure of the outer deposit differs markedly from that of the deposit during the initial stages, then a transitional growth stage may be involved. The structures of deposits studied in the present work tended to be fine grained in the initial stages but developed coarser columnar structures due to selected grain growth with favoured grains becoming broader during the intermediate and final stages of growth.

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