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The Lachlan Fold Belt (Lachlan Orogen) of eastern Australia was part of a Paleozoic convergent plate margin that stretched around the supercontinent of Gondwana from South America to Australia. Lower Paleozoic (545–365 Ma) deep-water, quartz-rich turbidites, calcalkaline volcanic rocks, and voluminous granitic plutons dominate the Lachlan Orogen. These rocks overlie a mafic lower crust of oceanic affinity. Shortening and accretion of the Lachlan occurred through stepwise deformation and metamorphism from Late Ordovician (∼450 Ma) through early Carboniferous times, with dominant events at about 440–430 Ma and 400–380 Ma. The development and accretion of the Lachlan Orogen and other related belts within the Tasmanides added about 2.5 Mkm2 to the surface area of Gondwana. The sedimentary, magmatic, and deformational processes converted an oceanic turbidite fan system into continental crust of normal thickness. The addition of this recycled continental detritus and juvenile material to Australia represents an under-recognized continental crustal growth mechanism that has been important thoughout earth history.

The Lachlan Orogen, like many other orogenic belts, has undergone paradigm shifts from geosynclinal to plate-tectonic theory of evolution over the past 40 years. Initial plate-tectonic interpretations were based on lithologic associations and recognition of key plate-tectonic elements such as andesites and palaeo-subduction complexes. Understanding and knowledge of modern plate settings led to the application of actualistic models and the development of palaeogeographical reconstructions, commonly using a non-palinspastic base. Igneous petrology and geochemistry led to characterisation of granite types into 'I' and 'S', the delineation of granite basement terranes, and to nonmobilistic tectonic scenarios involving plumes as a heat source to drive crustal melting and lithospheric deformation. More recently, measurements of isotopic tracers (Nd, Sr, Pb) and U-Pb SHRIMP age determinations on inherited zircons from granitoids and detrital zircons from sedimentary successions led to the development of multiple component mixing models to explain granite geochemistry. These have focused tectonic arguments for magma genesis again more on plate interactions. The recognition of fault zones in the turbidites, their polydeformed character and their thin-skinned nature, as well as belts of distinct tectonic vergence has led to a major reassessment of tectonic development. Other geochemical studies on Cambrian metavolcanic belts showed that the basement was partly backarc basin-and forearc basin-type oceanic crust. The application of 40 Ar-39 Ar geochronology and thermochronology on slates, schist and granitoids has better constrained the timing of deformation and plutonism, and illite crystallinity and b o mica spacing studies on slates have better defined the background metamorphic conditions in the low-grade parts. The Lachlan deformation pattern involves three thrust systems that constitute the western Lachlan Orogen, central Lachlan Orogen and eastern Lachlan Orogen. The faults in the western Lachlan Orogen show a generalised east-younging (450-395 Ma), which probably relates to imbrication and rock uplift of the sediment wedge, because detailed analyses show that the décollement system is as old in the east as it is in the west. Overall, deformation in the eastern Lachlan Orogen is younger (400-380 Ma), apart from the Narooma Accretionary Complex ( ca 445 Ma). Preservation of extensional basins and evidence for basin inversion are largely restricted to the central and eastern parts of the Lachlan Orogen. The presence of dismembered ophiolite slivers along some major fault zones, as well as the recognition of relict blueschist metamorphism and serpentinite-matrix mélanges requires an oceanic setting involving oceanic underthrusting (subduction) for the western Lachlan Orogen and central Lachlan Orogen for parts of their history. Inhibited by deep weathering and a general lack of exposure, the recent application of geophysical techniques including gravity, aeromagnetic imaging and deep crustal seismic reflection profiling ...

The cause of common polygenic autoimmune diseases is not understood because of genetic and cellular complexity. Here, we pinpoint the action of a subset of autoimmune susceptibility loci in the NOD mouse strain linked to D1mit181, D2mit490, D7mit101, and D15mit229, which cause a generalized resistance to thymic deletion in vivo that applies equally to Aire-induced organ-specific gene products in the thymic medulla and to systemic antigens expressed at high levels throughout the thymus and affects CD4(+), CD4(+)8(+), and CD4(+)25(+) thymocytes. Resistance to thymic deletion does not reflect a general deficit in TCR signaling to calcineurin- or ERK-induced genes, imbalance in constitutive regulators of apoptosis, nor excessive signaling to prosurvival genes but is distinguished by failure to induce the proapoptotic gene and protein, Bim, during in vivo encounter with high-avidity autoantigen. These findings establish defects in thymic deletion and Bim induction as a key mechanism in the pathogenesis of autoimmunity.

Abstract.Ar-Ar data from fabric-forming white mica in slates, syntectonic quartz veins and granitic mylonites constrain the timing of metamorphism, deformation, and exhumation in the Lachlan orogen, Australia. These data also help define the tectonic evolution of the Tasmanides

Productivity in a CHO perfusion culture reactor was maximized when pCO(2) was maintained in the range of 30-76 mm Hg. Higher levels of pCO(2) (> 150 mm Hg) resulted in CHO cell growth inhibition and dramatic reduction in productivity. We measured the oxygen utilization and CO(2) production rates for CHO cells in perfusion culture at 5.55×10(-17) mol cell(-1) sec(-1) and 5.36×10(-17) mol cell(-1) sec(-1) respectively. A simple method to directly measure the mass transfer coefficients for oxygen and carbon dioxide was also developed. For a 500 L bioreactor using pure oxygen sparge at 0.002 VVM from a microporous frit sparger, the overall apparent transfer rates (k(L)a+k(A)A) for oxygen and carbon dioxide were 0.07264 min(-1) and 0.002962 min(-1) respectively. Thus, while a very low flow rate of pure oxygen microbubbles would be adequate to meet oxygen supply requirements for up to 2.1×10(7) cells/mL, the low CO(2) removal efficiency would limit culture density to only 2.4×10(6) cells/mL. An additional model was developed to predict the effect of bubble size on oxygen and CO(2) transfer rates. If pure oxygen is used in both the headspace and sparge, then the sparging rate can be minimized by the use of bubbles in the size range of 2-3 mm. For bubbles in this size range, the ratio of oxygen supply to carbon dioxide removal rates is matched to the ratio of metabolic oxygen utilization and carbon dioxide generation rates. Using this strategy in the 500 L reactor, we predict that dissolved oxygen and CO(2) levels can be maintained in the range to support maximum productivity (40% DO, 76 mm Hg pCO(2)) for a culture at 10(7) cells/mL, and with a minimum sparge rate of 0.006 vessel volumes per minute.A = volumetric agitated gas-liquid interfacial area at the top of the liquid, 1/mB = cell broth bleeding rate from the vessel, L/minCER = carbon dioxide evolution rate in the bioreactor, mol/min[CO(2)] = dissolved CO(2) concentration in liquid, M[CO(2)](*) = CO(2) concentration in equilibrium with sparger gas, M[CO(2)](**) = CO(2) concentration in equilibrium with headspace gas, MCO(2)(1) = dissolved carbon dioxide molecule in water[C(T)] = total carbonic species concentration in bioreactor medium, M[C(T)](F) = total carbonic species concentration in feed medium, MD = bioreactor diameter, mD(I) = impeller diameter, mD(b) = the initial delivered bubble diameter, mF = fresh medium feeding rate, L/minH(L) = liquid height in the vessel, mk(A) = carbon dioxide transfer coefficient at liquid surface, m/mink (infA) (supO) = oxygen transfer coefficient at liquid surface, m/min.

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