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Background: The beneficial effects of endovascular therapy (EVT) in acute ischemic stroke have been demonstrated in recent clinical trials using new-generation thrombectomy devices. However, the comparative effectiveness and safety of preceding intravenous thrombolysis (IVT) in this population has rarely been evaluated. Methods: From a prospective multicenter stroke registry database in Korea, we identified patients with acute ischemic stroke who were treated with EVT within 8 h of onset and admitted to 14 participating centers during 2008-2013. The primary outcome was a modified Rankin Scale (mRS) score at 3 months. Major secondary outcomes were successful recanalization defined as a modified Treatment in Cerebral Ischemia score of 2b-3, functional independence (mRS score 0-2), mortality at 3 months, and symptomatic hemorrhagic transformation (SHT) during hospitalization. Multivariable logistic regression analyses using generalized linear mixed models were performed to estimate the adjusted odds ratios (ORs) of preceding IVT. Results: Of the 639 patients (male, 61%; age 69 ± 12; National Institutes of Health Stroke Scale score of 15 [11-19]) who met the eligibility criteria, 458 received preceding IVT. These patients showed lower mRS scores (adjusted common OR, 1.38 [95% CI 0.98-1.96]). Preceding IVT was associated with successful recanalization (1.96 [1.23-3.11]) and reduced 3-month mortality (0.58 [0.35-0.97]) but not with SHT (0.96 [0.48-1.93]). Conclusion: In patients treated with EVT within 8 of acute ischemic stroke onset, preceding IVT may enhance survival and successful recanalization without additional risk of SHT, and mitigate disability at 3 months.

The recently discovered icosahedral quasicrystal (i-QC) in the ternary Au–Al–Yb system at the composition Au51Al34Yb15 is formed only in as-cast alloys and is metastable with decomposition to other crystalline phases upon annealing at 700 °C. Measuring the electronic transport coefficients (electrical resistivity, thermoelectric power, Hall coefficient), magnetic susceptibility and specific heat, we addressed the question of metastability of the i-Au–Al–Yb quasicrystalline phase by reconstructing the shape of the electronic density of states (DOS) in the vicinity of Fermi level ɛF with the aim to find out whether there exists a pseudogap in the DOS that could contribute to electronic stabilization of the icosahedral phase. The results have revealed that the DOS in the vicinity of ɛF exhibits a pronounced valley on a 100 meV energy scale with a sharp feature on a 10 meV scale, both being centered almost exactly at ɛF. This pseudogap is apparently not wide enough to ensure sufficient electronic energy gain of the order of a few 10 kJ/mol needed for the electronic stabilization of the icosahedral phase. A possible origin of metastability of the i-Au–Al–Yb quasicrystal and thermodynamic stability of its 1/1 cubic approximant of very similar composition is discussed. The sharp feature in the DOS at ɛF is proposed to originate from indirect interaction between localized Yb f-moments due to overlap of their polarization clouds in the presence of hybridization of the f and s states, which leads to a sharp resonance peak.

A wide diversity of ammonia-oxidizing archaea (AOA)within the phylum Thaumarchaeota exists and playsa key role in the N cycle in a variety of habitats. In thisstudy, we isolated and characterized an ammoniaoxidizingarchaeon, strain MY3, from a coal tarcontaminatedsediment. Phylogenetically, strain MY3falls in clade ‘Nitrosocosmicus’ of the thaumarchaeotalgroup I.1b. The cells of strain MY3 are large‘walnut-like’ cocci, divide by binary fission along acentral cingulum, and form aggregates. Strain MY3 ismesophilic and neutrophilic. An assay of 13C-bicarbonateincorporation into archaeal membrane lipidsindicated that strain MY3 is capable of autotrophy. Incontrast to some other AOA, TCA cycle intermediates,i.e. pruvate, oxaloacetate and a-ketoglutarate,did not affect the growth rates and yields of strainMY3. The attachment of cells of strain MY3 to XAD-7hydrophobic beads and to the adsorbent vermiculitedemonstrated the potential of strain MY3 to form biofilms.The cell surface was confirmed to be hydrophobicby the extraction of strain MY3 from an aqueousmedium with p-xylene. Our finding of a strong potentialfor surface attachment by strain MY3 may reflectan adaptation to the selective pressures in hydrophobicterrestrial environments.