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Based on hydrographic data and vertical distributions of tropical species of fish larvae (Diogenichthys laternatus, Vinciguerria lucetia, Bregmaceros bathymaster, and Auxisspp.), effects of “Godzilla El Niño 2015–2016” in the shallow oxygen minimum zone off Mexico were analyzed. Zooplankton samples were collected during four cruises, before (February 2010 and April 2012) and during (June 2015 and March 2016) the warm event. Temporal series of sea surface temperature revealed that June 2015 was the warmest June of the last years. Conservative temperature was >2°C higher than normal in the surface mixed layer, and the suboxic layer (4.4 µmol/kg) reached as shallow as 100 m depth. Unexpected results were that larval abundances were relatively high during the warm event, unlike zooplankton volumes, which declined. Before the warm event, V. lucetiaand Auxisspp. were more abundant in the surface mixed layer, while B. bathymasterand D. laternatusdominated in the thermocline and shallow hypoxic layer (44 µmol/kg). However, during the event in June 2015, all species were most abundant in the surface mixed layer, which implied that the species adapted to hypoxia had inverted their normal pattern of distribution, possibly as consequence of the rise of the suboxic layer; however, further observations are required to confirm this generality. Results showed no dramatic change in the total larval abundance during the warm event. Nevertheless, a differential response in their vertical distribution was evident in association with changes in the depth of the shallow hypoxic and suboxic layers. This might indicate adaptability of tropical species to prolonged periods of warming in the oceans. El Niño 2015–2016 the suboxic layer rise up to 100 m depth in the OMZ off MexicoVertical distribution of tropical fish larvae changed in association with the hypoxic and suboxic layer depths during the eventLarvae of species that inhabit the hypoxic layer inverted their distribution with the highest abundance in the surface layer

Negative energy perturbations may be linked to the instability of fronts and gravity currents, for instance when the latter have uniform potential vorticity (in the f-plane). The equatorial Gaussian jet u(y) = u(0) exp (-y1/L2), in a one-layer, reduced-gravity, β-plane model may also be unstable to negative energy perturbations, particularly when the meridional gradient of potential vorticity does not change sign.Thus, if the semi-width of the equatorial jet equals the deformation radius, L=R, the potential and planetary vorticities are proportional, and the northward gradient of the former is therefore positive everywhere (this flow has the structure of a steady Kelvin mode). A westward jet in this class is found to be unstable to varicose, negative-energy perturbations: a necessary condition for instability is that the flow be supercritical at the equator. The net energy transfer is from the perturbations, whose amplitude increases, to the mean flow, even though potential energy exchange is in the reverse direction. These energy transfers are of similar magnitude, but have signs opposite to those of the classical barotropic case, which is discussed next. (Total pseudo-energy, an order wave-amplitude squared conserved quantity, vanishes for a growing perturbation.)Narrower jets, L=0.4R, are unstable if the gradient of potential vorticity changes sign. The energy of the perturbation is positive. Most of the energy transfer is from the mean flow's kinetic energy to the perturbation's kinetic energy. This case is like the classical barotropic one, because divergence effects are negligible

All types of amyloidosis are structurally characterized by the cross beta-pleated sheet conformation of the fibrils, irrespective of their biochemical composition. The clinical observation that the anthracycline 4'-iodo-4'-deoxy-doxorubicin (IDOX) can induce amyloid resorption in patients with immunoglobulin light chain amyloidosis was the starting point for this investigation of its possible mechanism of action. IDOX binds strongly to all five types of natural amyloid fibrils tested: immunoglobulin light chains, amyloid A, transthyretin (methionine-30 variant), beta-protein (Alzheimer), and beta 2-microglobulin. Quantitative binding studies showed that IDOX, but not doxorubicin, binds strongly to amyloid fibrils. This binding is saturable and involves two apparently distinct binding sites with Kd values of 5.9 x 10(-11) M and 3.4 x 10(-9) M. IDOX inhibited in vitro insulin amyloid fibrillogenesis. In vivo studies using the experimental amyloid murine model confirmed the specific targeting of IDOX to amyloid deposits. Preincubation of amyloid enhancing factor with IDOX significantly reduced the formation of amyloid deposits. It is hypothesized that IDOX exerts its beneficial effects through the inhibition of fibril growth, thus increasing the solubility of existing amyloid deposits and facilitating their clearance. IDOX may represent the progenitor of a class of amyloid-binding agents that could have both diagnostic and therapeutic potential in all types of amyloidoses.