Eocene lizard from Germany reveals amphisbaenian origins

Amphisbaenia is a speciose clade of fossorial lizards characterized by a snake-like body and a strongly reinforced skull adapted for head-first burrowing. The evolutionary origins of amphisbaenians are controversial, with molecular data uniting them with lacertids, a clade of Old World terrestrial lizards, whereas morphology supports a grouping with snakes and other limbless squamates. Reports of fossil stem amphisbaenians have been falsified, and no fossils have previously tested these competing phylogenetic hypotheses or shed light on ancestral amphisbaenian ecology. Here we report the discovery of a new lacertid-like lizard from the Eocene Messel locality of Germany that provides the first morphological evidence for lacertid-amphisbaenian monophyly on the basis of a reinforced, akinetic skull roof and braincase, supporting the view that body elongation and limblessness in amphisbaenians and snakes evolved independently. Morphometric analysis of body shape and ecology in squamates indicates that the postcranial anatomy of the new taxon is most consistent with opportunistically burrowing habits, which in combination with cranial reinforcement indicates that head-first burrowing evolved before body elongation and may have been a crucial first step in the evolution of amphisbaenian fossoriality.     

Palaeolithic paintings. Evolution of prehistoric cave art

Sophisticated examples of European palaeolithic parietal art can be seen in the caves of Altamira, Lascaux and Niaux near the Pyrenees, which date to the Magdalenian period (12,000-17,000 years ago), but paintings of comparable skill and complexity were created much earlier, some possibly more than 30,000 years ago. We have derived new radiocarbon dates for the drawings that decorate the Chauvet cave in Vallon-Pont-d'Arc, Ardèche, France, which confirm that even 30,000 years ago Aurignacian artists, already known as accomplished carvers, could create masterpieces comparable to the best Magdalenian art. Prehistorians, who have traditionally interpreted the evolution of prehistoric art as a steady progression from simple to more complex representations, may have to reconsider existing theories of the origins of art.     

Dwarfism in an adolescent from the Italian late Upper Palaeolithic

There have been numerous reports of pathological conditions in the hominid fossils, but these have only involved trauma or age-related deterioration in the health of otherwise normal individuals. Here we describe a skeleton of a young male from Riparo del Romito in Calabria, dated to the Epi-Gravettian of southern Italy. The preserved skeletal elements show that this individual (Romito 2) had the skull and long-bone morphology consistent with a mesomelic form of dwarfism, most probably the autosomal recessive disorder acromesomelic dysplasia. Generally recognized at birth, persons with acromesomelic dysplasia usually have normal intelligence and are free of serious medical problems. However, growth deficiency is severe (adult height typically is 110-120 cm) and mobility at the elbows is restricted. These physical impairments would have greatly interfered with the individual's participation in subsistence activities and would have been a substantial handicap in a nomadic hunting and gathering group. Thus, besides being the earliest known case of dwarfism in the human record, this skeleton provides evidence of tolerance of, and care for, a severely deformed individual in the Palaeolithic.     

Direct dating of Early Upper Palaeolithic human remains from Mladec

The human fossil assemblage from the Mladec Caves in Moravia (Czech Republic) has been considered to derive from a middle or later phase of the Central European Aurignacian period on the basis of archaeological remains (a few stone artefacts and organic items such as bone points, awls, perforated teeth), despite questions of association between the human fossils and the archaeological materials and concerning the chronological implications of the limited archaeological remains. The morphological variability in the human assemblage, the presence of apparently archaic features in some specimens, and the assumed early date of the remains have made this fossil assemblage pivotal in assessments of modern human emergence within Europe. We present here the first successful direct accelerator mass spectrometry radiocarbon dating of five representative human fossils from the site. We selected sample materials from teeth and from one bone for 14C dating. The four tooth samples yielded uncalibrated ages of approximately 31,000 14C years before present, and the bone sample (an ulna) provided an uncertain more-recent age. These data are sufficient to confirm that the Mladec human assemblage is the oldest cranial, dental and postcranial assemblage of early modern humans in Europe and is therefore central to discussions of modern human emergence in the northwestern Old World and the fate of the Neanderthals.     

Uranium series dates from Qesem Cave,Israel, and the end of the Lower Palaeolithic

Israel is part of a geographical 'out of Africa' corridor for human dispersals. An important event in these dispersals was the possible arrival of anatomically modern humans in the Levant during the late Middle Pleistocene. In the Levant the Lower Palaeolithic ends with the Acheulo-Yabrudian complex, characterized by technological developments, including the introduction of technological innovations such as the systematic production of blades and the disappearance of hand-axes. These reflect new human perceptions and capabilities in lithic technology and tool function. Qesem Cave, discovered in 2000, has a rich, well-preserved Acheulo-Yabrudian deposit holding great promise for providing new insights into the period. Here we report the dates of this deposit obtained by uranium isotopic series on associated speleothems and their implications. The results shed light on the temporal range of the Acheulo-Yabrudian and the end of the Lower Palaeolithic, suggesting a long cultural phase between the Lower Palaeolithic Acheulian and the Middle Palaeolithic Mousterian phases, starting before 382 kyr ago and ending at about 200 kyr ago.     

英汉比喻的民族特点趣谈

任何一种语言都承载了丰富的文化内涵。比喻是人类语言中一种最有力的表现手段。在漫长的历史进程中,英汉两种语言都创造和积累了丰富多彩的比喻,但基于各自民族不同的文化意识,审美意识和价值观,使喻体蕴涵了典型的民族特征。本文主要探讨英汉比喻的民族特点,及它们各自的文化内涵。     

成都金沙出土古象牙赋存环境研究

为了查明成都金沙出土古象牙赋存的物理化学条件,为其有效保护提供科学依据,对古象牙赋存环境(土壤)的物相、化学成分、pH值和Eh值进行了测试分析,并与古象牙的pH值、Eh值等特征进行了对比分析,结果表明:古象牙赋存土壤样品主要由粘土及硅酸盐矿物组成,其中蒙脱石、伊利石、绿泥石等粘土矿物含量达43%～60%,其pH值和Eh值的平均值分别为6.5和-13.5 mV,这种弱酸性还原环境的形成与土壤中含有0.3%左右的腐殖酸有着密切的关系.由于成都金沙古象牙pH和Eh值平均分别为6.46和-15.5 mV,与土壤pH和Eh值非常接近;并由于土壤中蒙脱石等粘土矿物的封闭作用,能够阻止古象牙与外部环境的物质交换及其对古象牙侵蚀作用,使古象牙能够在一种相对平衡的条件下得以长期保存.     

英汉比喻的民族特点趣谈

任何一种语言都承载了丰富的文化内涵.比喻是人类语言中一种最有力的表现手段.在漫长的历史进程中,英汉两种语言都创造和积累了丰富多彩的比喻,但基于各自民族不同的文化意识,审美意识和价值观,使喻体蕴涵了典型的民族特征.本文主要探讨英汉比喻的民族特点,及它们各自的文化内涵.     

Newly discovered Palaeolithic artefacts from loess deposits and their ages in Lantian,central China

Eight new Palaeolithic open-air sites were identified and 770 stone artefacts were collected from 2009 to 2011 in the Lantian area of the Bahe River valley, central China. Because the famous Homo erectus fossils were unearthed at the Gongwangling and Chenjiawo localities, and more than 30 Palaeolithic open-air sites were investigated in the 1960s in this region, the catchment of Bahe River is regarded as one of the most important hominin sites from the late early Pleistocene to the middle Pleistocene. These eight newly discovered open-air sites are located at the second(n = 6), third(n = 1) or higher terraces(n = 1) of the Bahe River. The Diaozhai section on the second terrace was sampled in detail. Two samples were collected for optically stimulated luminescence dating(OSL). The OSL results suggest that a buried lithic artefact layer at the Diaozhai site spans approximately 70–30 ka. The lithic assemblage analysis suggests that the stone artefacts were made of local pebbles/cobbles such as greywacke, quartz, sandstone and igneous rocks. The main percussion techniques that were used were direct hard hammer percussion and bi-polar techniques. The lithic artefacts comprise hammer stones, cores, flakes, retouched tools and flaking debris. Acheulian-type large cutting tools(LCTs) such as hand-axes, picks and cleavers were indentified in the Lantian region as well. This is the first time Acheulian-type LCTs from the late Pleistocene have been identified in this region. This study distinguishes age gaps between Western world and East Asian Acheulian-type tools.     

Frictional ageing from interfacial bonding and the origins of rate and state friction

Earthquakes have long been recognized as being the result of stick-slip frictional instabilities. Over the past few decades, laboratory studies of rock friction have elucidated many aspects of tectonic fault zone processes and earthquake phenomena. Typically, the static friction of rocks grows logarithmically with time when they are held in stationary contact, but the mechanism responsible for this strengthening is not understood. This time-dependent increase of frictional strength, or frictional ageing, is one manifestation of the 'evolution effect' in rate and state friction theory. A prevailing view is that the time dependence of rock friction results from increases in contact area caused by creep of contacting asperities. Here we present the results of atomic force microscopy experiments that instead show that frictional ageing arises from the formation of interfacial chemical bonds, and the large magnitude of ageing at the nanometre scale is quantitatively consistent with what is required to explain observations in macroscopic rock friction experiments. The relative magnitude of the evolution effect compared with that of the 'direct effect'--the dependence of friction on instantaneous changes in slip velocity--determine whether unstable slip, leading to earthquakes, is possible. Understanding the mechanism underlying the evolution effect would enable us to formulate physically based frictional constitutive laws, rather than the current empirically based 'laws', allowing more confident extrapolation to natural faults.     

A Middle Miocene hominoid from Thailand and orangutan origins

The origin of orangutans has long been debated. Sivapithecus is considered to be the closest ancestor of orangutans because of its facial-palatal similarities, but its dental characteristics and postcranial skeleton do not confirm this phylogenetic position. Here we report a new Middle Miocene hominoid, cf. Lufengpithecus chiangmuanensis n. sp. from northern Thailand. Its dental morphology relates it to the Pongo clade, which includes Lufengpithecus, Sivapithecus, Gigantopithecus, Ankarapithecus and possibly Griphopithecus. Our new species displays striking dental resemblances with living orangutans and appears as a more likely candidate to represent an ancestor of this ape. In addition, it originates from the geographic area of Pleistocene orangutans. But surprisingly, the associated flora shows strong African affinities, demonstrating the existence of a temporary floral and faunal dispersal corridor between southeast Asia and Africa during the Middle Miocene, which may have played a critical role in hominoid dispersion.     

试论舞蹈艺术与篮球艺术的异同

舞蹈艺术与篮球艺术互有交叉。探讨两者的关系是为了更好的发展舞蹈艺术、更好的利用身体艺术、更好的开发身体的资源,从另一个角度去审视舞蹈艺术的魅力．从舞蹈艺术和篮球艺术的统一性出发,分别剖析身体、路线、时间、指导思想、形态上的运动轨迹,寻找相互的共同点;并从舞蹈艺术和篮球艺术的存异性出发,分别对节奏控制、高潮设置和角色扮演的不同进行挖掘与研究．寻求两者的相互碰撞、相互影响．丰富人体艺术研究的方法．     

从西北雕刻看中国古代艺术之精神

通过对中国古代雕刻的思考，更加确定了中国古代艺术是摆脱真实物象的纯意象的造型艺术，中国的艺术空间是存在意念中。中国艺术以线造型，西方艺术以体、面造型，中西方艺术中空间观念和造型观念是不可分割的整体。     

MarcQuinn服装设计艺术的本质及其产生

英国时装设计师亚历山大·麦克奎恩（AlexanderMcQueen）在国际时装界被誉为“一代奇才”,然而他短暂的职业生涯却并不辉煌。尽管他天才的艺术设计在T台上光彩照人,可是在市场的实际检验中却显得黯然失色。形成这种反差的根本原因是其设计理念、设计风格及其艺术本质和产生的过程与其他服装设计师大相径庭。通过对亚历山大·麦克奎恩（AlexanderMcQueen）作品解读分析,廓清面貌,探究实质,有利于消解服装设计界的困惑,也是为今后时装设计走向提供借鉴。     

RNA evolution and the origins of life

The evolution of RNA is likely to have played an important role in the very early history of life on Earth but it is doubtful that life began with RNA. Consideration of what came before RNA must take into account relevant information from geochemistry, prebiotic chemistry and nucleic acid biochemistry.     

The origins and the future of microfluidics

The manipulation of fluids in channels with dimensions of tens of micrometres--microfluidics--has emerged as a distinct new field. Microfluidics has the potential to influence subject areas from chemical synthesis and biological analysis to optics and information technology. But the field is still at an early stage of development. Even as the basic science and technological demonstrations develop, other problems must be addressed: choosing and focusing on initial applications, and developing strategies to complete the cycle of development, including commercialization. The solutions to these problems will require imagination and ingenuity.     

从《地狱图》看芥川龙之介的人生观和艺术观

通过对芥川龙之介的作品《地狱图》的分析，阐明了芥川龙之介的人生观和艺术观，即追求艺术、崇尚艺术、为艺术无所顾忌的艺术至上思想。