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A solid solution series of lithium nickel metal oxides, Li[Ni(1-x)M(x)]O2 (with M = Co, Mn, and Al) have been investigated intensively to enhance the inherent structural instability of LiNiO2. However, when a voltage range of Ni-based cathode materials was increased up to >4.5 V, phase transitions occurring above 4.3 V resulted in accelerated formation of the trigonal phase (P3m1) and NiO phases, leading to and pulverization of the cathode during cycling at 60 °C. In an attempt to overcome these problems, LiNi0.62Co0.14Mn0.24O2 cathode material with pillar layers in which Ni(2+) ions were resided in Li slabs near the surface having a thickness of ∼10 nm was prepared using a polyvinylpyrrolidone (PVP) functionalized Mn precursor coating on Ni0.7Co0.15Mn0.15(OH)2. We confirmed the formation of a pillar layer via various analysis methods (XPS, HRTEM, and STEM). This material showed excellent structural stability due to a pillar layer, corresponding to 85% capacity retention between 3.0 and 4.5 V at 60 °C after 100 cycles. In addition, the amount of heat generation was decreased by 40%, compared to LiNi0.70Co0.15Mn0.15O2.

Ultralong germanium nanotubes (Ge NTs; see picture) are synthesized in high yield from core–shell Ge–Sb nanowires by utilizing the Kirkendall effect at 700 °C. The Ge NTs have an exceptionally high rate capability (40 Ag−1) while maintaining a reversible capacity of more than 1000 mAhg−1 over 400 cycles, with minimal capacity fading when paired with a LiCoO2 cathode in a lithium‐ion cell.

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Figure 3 in the above article contained an erroneous spectra in part b. The corrected figure is shown below in full: Figure 3. a-b) X-ray photoelectron spectroscopy (XPS) profi les of the core-shell (HSLiNi 0.54 Co 0.12 Mn 0.34 O 2) particles before etching (a) and after etching to depths of 5, 30, 60 and 90 nm (b). The authors apologize for any inconvenience caused.

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Tumor suppressor programmed cell death protein 4 (PDCD4) inhibits the translation initiation factor eIF4A, an RNA helicase that catalyzes the unwinding of secondary structure at the 5 -untranslated region of mRNAs and controls the initiation of translation. Here, we determined the crystal structure of the human eIF4A and PDCD4 complex. The structure reveals that one molecule of PDCD4 binds to the two eIF4A molecules through the two different binding modes. While the two MA3 domains of PDCD4 bind to one eIF4A molecule, the C-terminal MA3 domain alone of the same PDCD4 also interacts with another eIF4A molecule. The eIF4A-PDCD4 complex structure suggests that the MA3 domain(s) of PDCD4 binds perpendicular to the interface of the two domains of eIF4A, preventing the domain closure of eIF4A and blocking the binding of RNA to eIF4A, both of which are required events in the function of eIF4A helicase. The structure, together with biochemical analyses, reveals insights into the inhibition mechanism of eIF4A by PDCD4 and provides a framework for designing chemicals that target eIF4A.translation inhibition ͉ tumor suppressor ͉ RNA helicase ͉ domain closure ͉ MA3 domain P rogrammed cell death protein 4 (PDCD4) is a translation inhibitor that suppresses neoplastic transformation in cultured cells and transgenic mice (1-3). Loss or reduced expression of PDCD4 has been implicated in the development and progression of a variety of aggressive human cancers (4-6). PDCD4 is regulated by the S6K1 kinase and the SCF ␤TRCP ubiquitin ligase in response to the activation of the mTOR pathway by mitogens, and the controlled degradation of PDCD4 is essential for efficient protein synthesis and consequently for cell growth and proliferation (7).PDCD4 is believed to perform its tumor suppressor function primarily through interaction with eIF4A and eIF4G, which are components of mRNA-binding complex eIF4F (8). eIF4A is a DEAD-box RNA helicase, with two domains, that unwinds the secondary structures in 5Ј-untranslated region (UTR) and cap of mRNA and thereby facilitates ribosome scanning (8). eIF4G is an adaptor protein that coordinates assembly of translation factors and the small ribosomal subunit (8). PDCD4 is believed to inhibit cap-dependent translation by directly inhibiting the helicase activity of eIF4A or by competing with eIF4G for binding to eIF4A and preventing assembly into a eukaryotic initiation complex, eIF4F, or both (1, 9, 10).PDCD4 is formed with the two MA3 domains at its middle (mMA3) and C-terminal regions (cMA3) (9, 11-13). Mutational and NMR binding analysis have shown that PDCD4 uses both MA3 domains to interact with eIF4A and prevents translation (9, 10). However, other studies have demonstrated that the cMA3 domain alone is sufficient for the inhibition of RNA helicase and translation (12). The interactions between eIF4A and PDCD4 have been analyzed in several mutational and NMR mapping studies (1, 9, 10). Nevertheless, it is unclear from these studies how PDCD4 inhibits eIF4A at the molecular level. To elucidate ...

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