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The iota toxin produced by Clostridium perfringenstype E is a binary toxin comprising two independent polypeptides: Ia, an ADP-ribosyltransferase, and Ib, which is involved in cell binding and translocation of Ia across the cell membrane. Here we report cryo-EM structures of the translocation channel Ib-pore and its complex with Ia. The high-resolution Ib-pore structure demonstrates a similar structural framework to that of the catalytic ϕ-clamp of the anthrax protective antigen pore. However, the Ia-bound Ib-pore structure shows a unique binding mode of Ia: one Ia binds to the Ib-pore, and the Ia amino-terminal domain forms multiple weak interactions with two additional Ib-pore constriction sites. Furthermore, Ib-binding induces tilting and partial unfolding of the Ia N-terminal α-helix, permitting its extension to the ϕ-clamp gate. This new mechanism of N-terminal unfolding is crucial for protein translocation.

Changes in terrestrial water storage are likely to affect sea level, but comprehensive and reliable data are scarce. Simulations of global terrestrial water stocks and flows, with an integrated model that specifically accounts for human activities, indicate that groundwater depletion and reservoir storage have together led to a sea-level rise of about 0.66 mm yr−1between 1961 and 2003, about 36% of the observed rise.

The hydropolitics over the Abbay basin has a long history of hydrologic hegemony by Egypt. The conflict over the Abbay River mainly occurred between Egypt, Ethiopia, and Sudan. Even though the river is shared by 11 countries, the use is principally dominated by Egypt in the last decades. This paper aimed to review the hydropolitics of Abbay/Blue Nile, its challenges, opportunities, and also the impacts of constructing the GERD over the riparian states (Ethiopia, Egypt, and Sudan). This review was done by searching and reviewing of papers published in reputable journals (peer reviewed and open access) focused on Abbay Basin, GERD and transboundary rivers. Egyptians said that Abbay is the primary water resource and their lifeblood and desires to continue their power on the Abbay basin. On the opposite side, Ethiopia, contributing about 86% of the flow has not been benefited from the river. This controversy has brought disagreement between Ethiopia, Egypt, and Sudan but mainly the tensions between Egypt and Ethiopia are running high. For the last 40 years, the two nations haven't experienced such resistance. However, the starting of the construction of the Grand Ethiopian Renaissance Dam (GERD) brought deviation. Ethiopians are constructing the dam over the river Abbay by their source of finance and people for ensuring their capacity and the moral issue of the people. Egypt’s hydrological hegemony on the Abbay river is reversed from the dominance of one state to the equitable and benefit-sharing of the transboundary river. Even though, the standard water program has been developed, the riparian states haven't entirely approved it due to current and projected water needs, conflict of interest, little data, and lack of mutual aid. The variety of hydrological processes within the Abbay basin makes it challenging to implement a standard plan that could be applied for overall riparian states. Although Egypt and Sudan are resisting the efforts to incorporate the other upstream riparian’s within the negotiations, they have to understand that the river and its management must be advanced from a regional viewpoint. The development of GERD within the Abbay river by Ethiopia has a positive impact on downstream countries because it provides electricity, regulates the flow, controls flood, and reduces the cost of reservoir maintenance in downstream dams. A comprehensive understanding of hydrological processes is currently essential for effective water management in the Abbay basin.

A numerical computation of the 2011 Tohoku earthquake tsunami was performed to identify fundamental features of the tsunami evolution along the coast of Hokkaido, Japan. Edge waves formed at multiple locations where the refracted tsunami focused, governing local surface oscillations and regional variations in tsunami height along the Pacific coast of Hokkaido. The computation reasonably reproduced the distribution of surveyed tsunami height as well as the time records of surface elevation recorded at ports in Hokkaido. The major features of the frequency spectrum for the 2011 Tohoku tsunami were identical to those for the 2003 Tokachi-oki earthquake tsunami; inherent local properties of surface oscillation caused by the passage of edge waves existed, determined by the local bathymetry.