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The unique aluminum–carbon interface without carbide, which is termed as the directly bonded aluminum–carbon interface, is a recently reported remarkable structure for simultaneously enhancing the load/electron transfer properties of aluminum conductors. In this paper, the structure of the directly bonded aluminum–carbon interface in aluminum–carbon composites fabricated by solid-state friction stir processing is reported on an atomic scale for the first time. The atomically resolved structure of two typical interfaces, Al-200 | G-end interface and Al-311 | G-side interface, are investigated by using high-resolution transmission electron microscopy. Interfacial distance analysis shows that both interfaces are bonded via chemical bonds, other than van der Waals forces. The Al-200 | G-end interface is found to be in a semicoherent mode, in which every five Al-(200) planes are bonded directly with three basal planes in graphite. Atomically resolved interfacial matching patterns of the Al-311 | G-side interface are proposed based on the observed atomic plane matching relationship. This work provides new insights into the atomic scale of the aluminum–carbon interface for the development of high-performance aluminum conductors. [ABSTRACT FROM AUTHOR]

The sabertoothed cat Megantereon is an iconic carnivore in the Pleistocene of Eurasia, yet its fossil record is extremely rare and highly fragmentary in southern China (and the whole Oriental Realm). Here we report a nearly complete and undeformed skull of Megantereon from Sabretooth Cave, Chongzuo, southernmost China, middle Early Pleistocene. The general morphology allows us to assign it to Megantereon nihowanensis, differing from the northern China population of M. nihowanensis by better developed P4 parastyle and longer c-p3 diastema. The excellent preservation allows us to exam the previous unrecognised cranial characters. Megantereon shows a clear affinity to Smilodon in many aspects, e.g. wide nasal with parallel lateral border and smoothly curved posterior border, presence of moderately developed antero-medial process of the nasal, presence of anterior accessory process of the frontal, and a distinct frontal depression behind the posterior border of the nasal. These characters are markedly different from those of Homotherium, suggesting a deep divergence of the two lineages of sabertoothed cats. The rarity of Megantereon in southern China and southeastern Asia probably suggests this genus is not well adaptive to the closed forest environment. [ABSTRACT FROM AUTHOR]

The Quaternary record of fossil snakes (Reptilia, Squamata) in Asia is extremely rare; any information is noteworthy. An articulated snake skeleton was recovered from the early Pleistocene (2.15–2.14 Ma) deposits in Renzidong Cave, Yangtze River Valley, east-central China. The skeleton contains about 122 nearly complete vertebrae but lacks the cranium and caudal vertebrae. Preserved vertebral characters indicate that the snake is particularly similar to the rat snake,Elaphe(Colubridae) especially with the EuropeanElaphe praelongissima(late Miocene). We identify the specimen as cf.Elaphesp. This genus and ‘Colubers.l.’ are unfortunately similar and difficult to differentiate based on just vertebral comparisons of species living in Europe. Adequate comparative skeletons of living snakes of eastern Asia are noticeably absent in museums making identifications of fossil specimens less than satisfactory. Finding dated fossil remains of the snakeElaphein Asia holds importance to the understanding of its time of dispersal between Asia, Europe and North America, but this can only be adequately examined with fossil remains accurately and satisfactorily identified. [ABSTRACT FROM PUBLISHER]

The Early Cretaceous long bony-tailed bird Jeholornis prima displays characters both more basal than Archaeopteryx and more derived, exemplifying the mosaic distribution of advanced avian features that characterises early avian evolution and obfuscates attempts to understand early bird relationships. The current diversity of Jeholornithiformes is controversial, since multiple possibly synonymous genera were named simultaneously. Here, we provide the first definitive evidence of a second species belonging to this clade, and erect the new taxon J. palmapenis sp. nov. This new specimen reveals the tail integument of Jeholornithiformes, the morphology of which appears to have no aerodynamic benefit suggesting this clade evolved plumage patterns that were primarily for display. [ABSTRACT FROM PUBLISHER]

The Yiyuan hominin fossil site is one of the few localities in China where a partial skullcap and several loose teeth of Homo erectus have been discovered. Yiyuan was previously assigned broadly to the Middle Pleistocene by biostratigraphical correlation and ESR/U-series dating. Here, we report the first application of a radio-isotopic dating method to the site. 26Al/10Be burial dating results derived from two sand samples from the fossiliferous deposits show that the hominin fossils can be confidently dated to 0.64 ± 0.08 Ma (million years ago). The reliability of this age is supported by the zero age of modern fluvial sediment near the cave. Our result is consistent with the age estimation based on biostratigraphic correlation and supports the argument that the Yiyuan and Zhoukoudian Locality 1 H. erectus fossils are contemporaneous. The results presented here, along with other recent chronological studies on Chinese Middle Pleistocene hominin sites, indicate that the time span from 600–400 ka (thousand years ago) is a critical period for human evolution in East Asia. Importantly, this time bracket includes several major climatic changes that would have influenced hominins, both morphologically and behaviorally. [ABSTRACT FROM AUTHOR]

Abstract: The world''s definite southernmost woolly mammoth record is a molar from Ji’nan (around 36°N), Shandong Province, China. AMS 14C dating of the specimen, gave a conventional 14C age of 33,150±250BP. The period of 40–30kaBP corresponds to the later phase of the Marine Oxygen Isotope Stage 3 (MIS 3a), recognized as the global interstadial of the last glacial period. However, it is known that the winter monsoon strengthened in Asia during the period 35–33kaBP, and the age of the woolly mammoth specimen from Ji’nan corresponds to that age. The specimen suggests that this area became cold and dry in 33kaBP, and grassland or open forest, suitable habitat for woolly mammoths, developed during this short time span. This age is similar to the age of the southernmost woolly mammoth record in Europe, therefore supporting a hypothesis by Porter and An [1995. Correlation between climate events in the North Atlantic and China during the last glaciation. Nature 375, 305–308] that an important component of Chinese palaeoclimates may be linked to changes in North Atlantic oceanic conditions. [Copyright &y& Elsevier]