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SummaryCytoplasmic microtubules (MTs) serve as a ratelimiting factor for hyphal tip growth in the filamentous fungus Aspergillus nidulans. We hypothesized that this function depended on the MT plus end-tracking proteins (+TIPs) including the EB1 family protein EBA that decorated the MT plus ends undergoing polymerization. The ebAΔ mutation reduced colony growth and the mutant hyphae appeared in an undulating pattern instead of exhibiting unidirectional growth in the control. These phenotypes were enhanced by a mutation in another +TIP gene clipA. EBA was required for plus end-tracking of CLIPA, the Kinesin-7 motor KipA, and the XMAP215 homologue AlpA. In addition, cytoplasmic dynein also depended on EBA to track on most polymerizing MT plus ends, but not for its conspicuous appearance at the MT ends near the hyphal apex. The loss of EBA reduced the number of cytoplasmic MTs and prolonged dwelling times for MTs after reaching the hyphal apex. Finally, we found that colonies were formed in the absence of EBA, CLIPA, and NUDA together, suggesting that they were dispensable for fundamental functions of MTs. This study provided a comprehensive delineation of the relationship among different +TIPs and their contributions to MT dynamics and unidirectional hyphal expansion in filamentous fungi.

A highly efficient Rh-catalyzed hydrogenation of functionalized olefins has been realized by a new family of highly rigid chiral ferrocenylphosphine-spiro phosphonamidite ligands. Excellent enantiocontrol (>99% ee in most cases) was achieved with a wide range of α-dehydroamino acid esters and α-enamides. This practicable catalytic system was further applied in the scalable synthesis of highly optically pure key intermediates of cinacalcet and D-phenylalanine.

Among coal-producing countries, China has witnessed the highest frequency and severity of coal fires. During mining in the re-mining face and the lower part of the thick coal seam (or coal seam group), second or multiple oxidations of the residual coal can readily occur in mined-out areas, severely increasing the risk of coal fires. The study of multiple oxidations of coal aids in the early detection of spontaneous combustion of remaining coal in the mined-out areas. The characteristics of coal fires are demonstrated using fresh coal samples (first-oxidized coal) and oxidized coal samples (second-oxidized coal) from four different ranks of coals. Proximate and elemental analysis, Fourier transform spectroscopy, and thermogravimetry-differential scanning calorimetry were adopted to investigate the quality, microcharacteristics, characteristic temperatures, and apparent activation energy of second-oxidized coal. In addition, the effect of spontaneous combustion at heating rates of 5.0, 10.0, and 15.0°C min -1 was studied. Compared with the four samples of first-oxidized coal, those of second-oxidized coals cause fire easily under the same conditions. List of symbolsA, A k Pre-exponential factor (s -1 ) A ad Ash content in air-dried basis (%) bHeating rate (°C min -1 ) C daf C content of air-dried basis (%) da/dt Conversion rate (s -1 ) E a , E k Apparent activation energy (kJ mol -1 ) f(a)Function of degree of conversion (dimensionless) H daf H content of air-dried basis (%) M ad Moisture in air-dried basis (%) N daf N content of air-dried basis (%) R Universal gas constant (8.314 J mol -1 K -1 ) r Correlation coefficient (dimensionless) O daf O content of air-dried basis (%) S daf S content of air-dried basis (%) T Thermokinetic temperature (K) T 1 First characteristic temperature, critical temperature (°C) T 2 Second characteristic temperature, active temperature (°C) T 3 Third characteristic temperature, pyrolysis temperature (°C) T 4 Fourth characteristic temperature, ignition temperature (°C) T 5 Fifth characteristic temperature, burned-out temperature (°C)

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