Re-dating Zhoukoudian Upper Cave, northern China and its regional significance.

Due to the presence of multiple partial modern human skeletons thought to have been interred along with a diversity of evidence of symbolic behavior, Zhoukoudian Upper Cave (ZKD UC; formally "Choukoutien") from northern China has long been a critical site for understanding Late Quaternary human evolution and particularly the role eastern Asia played. Unfortunately, uncertainty regarding ZKD UC's chronology has long hindered determination of its importance in the debate over modern human origins. This situation has been particularly problematic because dates from the primary archaeological layers of ZKD UC have ranged from the Late Pleistocene to the Early Holocene (∼34-10 ka), with clearly different implications depending on which age is used. Here, we present a new set of accelerator mass spectrometry radiocarbon dating results from ZKD UC. Based on this new set of dates and further re-evaluations of the previous dating analyses, archaeological materials, published excavation reports and stratigraphy, we conclude that the ZKD UC archaeological layers minimally date to 35.1-33.5 ka. Given the similarities between the human fossils and archaeology between ZKD UC and western Eurasia, it is likely that the ZKD UC human foragers were part of dispersal events across northern Eurasia toward Siberia and eventually reaching into northern China.

The origin and evolution of sewing technologies in Eurasia and North America.

When, how, and following which paths hominins created the innovations that allowed them to colonize regions of the planet that were not suited to their thermal physiology is still a matter of inquiry. In this paper, we elaborate a theoretical framework to investigate the origin and diversification of bone needles, summarize the evidence for their emergence, create a large database of their morphometric and stylistic characters, and present results of the study of an exceptionally well-preserved collection of needles from Shuidonggou Locality 12 (SDG12), a site located in the Ningxia Hui Autonomous Region, Northern China, dated to ca. 11.2 ka BP. Bone needles are reported from 271 sites and 355 archaeological layers. Revision of the evidence shows they represent an original cultural innovation that emerged in Eurasia between 45-40 ka BP. Size differences between the earliest known specimens, found in Siberia and China, indicate needles may have been invented independently in these two regions. Needles from Eastern Europe may represent either an independent invention or a geographic extension of earlier Siberian and Caucasian sewing traditions. In Western Europe, needles appear during the Solutrean. The wider size range characteristic of Magdalenian specimens supports the idea that needles of different sizes were used in a variety of tasks. In China, the robust sub-circular needles found at sites dated between 35-25 ka BP are followed, between 26-23 ka BP, by small flat needles, which may represent an innovation associated with the microblades/microcores toolkit. At SDG12, technological, functional, and morphometric analyses of finished needles and manufacturing by-products identify two previously undetected reduction sequences for the production of needles of different size and, probably, function. The bone needles found at Paleoindian sites are the smallest and reflect a never previously achieved mastery in the production of such tools.

The easternmost Middle Paleolithic (Mousterian) from Jinsitai Cave, North China.

The dispersal of Neanderthals and their genetic and cultural interactions with anatomically modern humans and other hominin populations in Eurasia are critical issues in human evolution research. Neither Neanderthal fossils nor typical Mousterian assemblages have been reported in East Asia to date. Here we report on artifact assemblages comparable to western Eurasian Middle Paleolithic (Mousterian) at Jinsitai, a cave site in North China. The lithic industry at Jinsitai appeared at least 47-42 ka and persisted until around 40-37 ka. These findings expand the geographic range of the Mousterian-like industries at least 2000 km further to the east than what has been previously recognized. This discovery supplies a missing part of the picture of Middle Paleolithic distribution in Eurasia and also demonstrates the makers' capacity to adapt to diverse geographic regions and habitats of Eurasia.

Re-examination of the dates of large blade technology in China: a comparison of Shuidonggou Locality 1 and Locality 2.

The presence and age of large blade technology at the Shuidonggou site is a pivotal issue in discussions of the spread of blade technology in East Eurasia. Madsen and colleagues' influential work uses the dates (24,000-29,000 rcy BP [radiocarbon years before present]) they obtained from Shuidonggou Locality 2 to estimate the age of blade technology in this region, and suggested a very late arrival of Levallois-like blade technology from the north. This paper re-examines the evidence for the age of blade technology at Shuidonggou by comparing the lithic assemblages from the new excavations at Locality 2 with those from Locality 1. Several important points are demonstrated: (1) the lithic industry of cultural layers 1 through 4 at Locality 2 is not based on large blades, so reported dates from these layers cannot be an indicator of the age of large blade technology; (2) comparing Locality 1 and 2, the age of large blade technology appears to be around 34,000-38,000 calendar years BP (before present) in this region, suggesting a relatively rapid technology dispersal from the west and/or north; (3) the so-called 'Shuidonggou lower cultural layer' at Locality 1 includes both large blade and simple flake industries.

C-shaped porous polypropylene fibers for rapid oil absorption and effective on-line oil spillage monitoring.

Development of efficient absorbent materials for detection and treatment of offshore oil spillages remained a challenge. In this work, C-shaped polypropylene oil-absorbent fibers with sub-micron internal pores were prepared by combining spun-bonding technique and thermally induced phase separation (TIPS). The effect of drawing speed on the phase separation and the porous morphology of the shaped fiber non-woven fabric (NWF) was investigated. C-shaped NWF with porous morphology had large water contact angle, higher porosity, larger specific surface area, and increased oil absorption speed and capacity. An online oil spillage detection system was developed using porous C-shaped NWF and an oxygen sensing probe, showing shorter response time and higher signal-to-noise (STN) ratio. The response time for detecting the spillage of soybean oil and diluted crude oil (0.5 mL/0.8 L) in water were only 24 s and 10 s, respectively. The reliable oil detection low detection limit (RLDL) of the oxygen sensing probe was reduced 173 times (from 36.5 g/L to 0.21 g/L) when combined with C-shaped porous fiber NWF.

Development of coin-shaped ZIF-7 functionalized superhydrophobic polysulfone composite foams for continuous removal of oily contaminants from water.

Development of efficient absorbent materials for oil spillage clean-up and environmental pollution remediation is highly desired but remains a challenge. In this work, superhydrophobic/superoleophilic polysulfone based ZIF-7 composite (SPZ) foams were fabricated via chemical modification of polysulfone and integrating with hydrophobic coin-shaped ZIF-7 particles. The synergistic approaches provided the SPZ foams with high porosity, low density and superhydrophobic/superoleophilic features (θwater=162.3°, θoil=0°) and outstanding self-cleaning property. The as-prepared SPZ foams exhibited highly selective absorption capacity (up to 3800 wt%) for various kinds of oils and organic solvents. Furthermore, the SPZ foams still maintained 95.2% of its pristine absorption capacity and the θwater remained at 143.6° after ten absorption/distillation cycles. The SPZ foam showed outstanding separation ability towards different types of emulsions with separation efficiency all above 97%. The high oil/water separation efficiency and robust reusability made the SPZ foams promising absorbent in dealing with practical oil spills.

Intra-assemblage variation in the macro-blade assemblage from the 1963 excavation at Shuidonggou locality 1, northern China, in the context of regional variation.

The emergence of the Upper Paleolithic and regional variability in early Upper Paleolithic industries are prominent topics in Paleolithic archaeology, with special relevance to the dispersal and differentiation of early modern human cultures across Eurasia. The so-called Initial Upper Paleolithic (IUP) has been considered a key element in the emergence of the Upper Paleolithic in northern Asia. Here, we examine the intra-assemblage variation in the collection from the 1963 excavation at Shuidonggou locality 1, a major IUP site in northern China. We combine technological and quantitative attribute analyses to investigate the variety of core reduction sequences and tool manufacture behaviors at the site. A range of core reduction sequences have been documented at Shuidonggou locality 1, including both simple core reduction and prepared core reduction yielding laminar (blade-like) products. The simple core reduction component may due to mixed non-IUP assemblages from different archaeological layers. Among the laminar core reduction sequences, the main strategy involves asymmetrical exploitation of the broad face of core blank, producing blades and elongate flakes, and resembling a recurrent Levallois blade method sensu lato. We compare Shuidonggou laminar blank production with that of IUP assemblages in the Siberian Altai, northern Mongolia, and the Transbaikal region. The comparison demonstrates a general consistency to the basic blank production in IUP assemblages across northern Asia, with some regional variation. The results suggest a multi-directional model of diffusion of the IUP in northeast Asia.

An early modern human from Tianyuan Cave, Zhoukoudian, China.

Thirty-four elements of an early modern human (EMH) were found in Tianyuan Cave, Zhoukoudian, China in 2003. Dated to 42,000-39,000 calendrical years before present by using direct accelerator mass spectrometry radiocarbon, the Tianyuan 1 skeleton is among the oldest directly dated EMHs in eastern Eurasia. Morphological comparison shows Tianyuan 1 to have a series of derived modern human characteristics, including a projecting tuber symphyseos, a high anterior symphyseal angle, a broad scapular glenoid fossa, a reduced hamulus, a gluteal buttress, and a pilaster on the femora. Other features of Tianyuan 1 that are more common among EMHs are its modest humeral pectoralis major tuberosities, anteriorly rotated radial tuberosity, reduced radial curvature, and modest talar trochlea. It also lacks several mandibular features common among western Eurasian late archaic humans, including mandibular foramen bridging, mandibular notch asymmetry, and a large superior medial pterygoid tubercle. However, Tianyuan 1 exhibits several late archaic human features, such as its anterior to posterior dental proportions, a large hamulus length, and a broad and rounded distal phalangeal tuberosity. This morphological pattern implies that a simple spread of modern humans from Africa is unlikely.