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The sulfur stable isotopic values (d34S) of sulfate aerosols can be used to assess oxidation pathways and contributions from various sources, such as marine biogenic sulfur, volcanoes, and sea salt. However, because of a lack of observations, the spatial distribution of d34S values in Antarctic sulfate aerosols remains unclear. Here we present the first sulfur isotopic values from surface snow samples along a latitudinal transect in eastern Dronning Maud Land, East Antarctica. The d34S values of sulfate showed remarkably uniform values, in the range of 14.8–16.9‰, and no significant decrease toward the inland part of the transect was noted. These results suggest that net isotopic fractionation during long-range transport is insignificant. Thus, the d34S values can be used to infer source contributions. The d34S values suggest that marine biogenic sulfur is the dominant source of sulfate aerosols, with a fractional contribution of 84?±?16%. This study reports the first sulfur isotopic values of Antarctic snow along a latitudinal transectSmall sulfur isotopic variations indicate insignificant isotope fractionation during transportSulfur isotopic values suggest that biogenic sulfur dominates Antarctic sulfate aerosols

AbstractWe evaluated elevation changes at four sites on debris-covered ablation area of Khumbu Glacier, Nepal Himalaya, since 1978. In 2004, we carried out a ground survey by differential GPS in the upper- and lowermost areas of the ablation area. The amount of surface lowering was calculated by comparing digital elevation models (DEMs) with 30-m grid size, as generated from survey data corrected in 1978, 1995, and in the present study. Because we could not access the middle parts of the debris-covered area due to surface roughness, for this area we used an ASTER-DEM calibrated by the ground survey data. The amount of surface lowering during the period 1978–2004 was insignificant near the terminus. A remarkable acceleration of surface lowering was found in the middle part of the debris-covered ablation area, where the glacier surface is highly undulating. In the uppermost area, surface lowering has continued at a steady rate. Surface flow speeds have decreased since 1956, revealing that the recent decrease in ice flux from the upper accumulation area would have accelerated the rate of surface lowering of the debris-covered area of Khumbu Glacier during the period 1995–2004.

We developed an anthropomorphic talking robot, Waseda Talker No. 6 (WT-6), which generates speech sounds by mechanically simulating articulatory motions and aero-acoustic phenomena. WT-6 possesses 17 degrees of freedom (DOF): a 5-DOF tongue, 1-DOF jaws, 4-DOF lips, a nasal cavity, and a 1-DOF soft palate as articulators; and 5-DOF vocal cords and 1-DOF lungs as vocal organs. The vocal cords, tongue, and lips are made from the thermoplastic rubber Septon, whose elasticity is similar to that of human tissue. WT-6 has three-dimensional (3D) lips, tongue, jaw, and velum, which form the vocal tract structure. It also has an independent jaw opening/closing mechanism. The previous robot in the series had a two-dimensional tongue and could not produce human-like tongue shape. The new tongue can form 3D shapes, and thus, is able to produce more realistic vocal tract shapes. The vocal cord model consists of two folds, and is constructed with a structure similar to the biomechanical structure of human vocal cords. These vocal cords can vibrate in complex phases, similar to those of a human. With these mechanisms, the robot can reproduce human speech in a more biomechanical manner, and thus, can produce a voice closer to that of a human.

We developed an anthropomorphic talking robot, Waseda Talker No. 6 (WT-6), which generates speech sounds by mechanically simulating articulatory motions and aero-acoustic phenomena. WT-6 possesses 17 degrees of freedom (DOF): a 5-DOF tongue, 1-DOF jaws, 4-DOF lips, a nasal cavity, and a 1-DOF soft palate as articulators; and 5-DOF vocal cords and 1-DOF lungs as vocal organs. The vocal cords, tongue, and lips are made from the thermoplastic rubber Septon, whose elasticity is similar to that of human tissue. WT-6 has three-dimensional (3D) lips, tongue, jaw, and velum, which form the vocal tract structure. It also has an independent jaw opening/closing mechanism. The previous robot in the series had a two-dimensional tongue and could not produce human-like tongue shape. The new tongue can form 3D shapes, and thus, is able to produce more realistic vocal tract shapes. The vocal cord model consists of two folds, and is constructed with a structure similar to the biomechanical structure of human vocal cords. These vocal cords can vibrate in complex phases, similar to those of a human. With these mechanisms, the robot can reproduce human speech in a more biomechanical manner, and thus, can produce a voice closer to that of a human.