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1.
古铜矿遗址围岩表层有害生物的防治   总被引:3,自引:0,他引:3  
铜绿山古铜矿遗址地处长江中游地区、空气湿度大、围岩表层有害生物成片生长蔓延,对遗址的长期保护造成极大威胁。对此采取了改变遗址的环境条件、喷涂消杀药品的方法,消除了围岩表层有害生物的危害。经过一年半的观察表明该方法是可行的。  相似文献   
2.
Accurate simulation of multiphase flow in fractured porous media remains a challenge. An important problem is the representation of the discontinuous or near discontinuous behaviour of saturation in real geological formations. In the classical continuum approach, a refined mesh is required at the interface between fracture and porous media to capture the steep gradients in saturation and saturation‐dependent transport properties. This dramatically increases the computational load when large numbers of fractures are present in the numerical model. A discontinuous finite element method is reported here to model flow in fractured porous media. The governing multiphase porous media flow equations are solved in the adaptive mesh computational fluid dynamics code IC‐FERST on unstructured meshes. The method is based on a mixed control volume – discontinuous finite element formulation. This is combined with the PN+1DG‐PNDG element pair, which has discontinuous (order N+1) representation for velocity and discontinuous (order N) representation for pressure. A number of test cases are used to evaluate the method's ability to model fracture flow. The first is used to verify the performance of the element pair on structured and unstructured meshes of different resolution. Multiphase flow is then modelled in a range of idealised and simple fracture patterns. Solutions with sharp saturation fronts and computational economy in terms of mesh size are illustrated.  相似文献   
3.
We present the palaeopathological analysis of a right fourth metatarsal (ATD6‐124) recovered from the Atapuerca–Gran Dolina site (Spain). This fossil, ca. 1 Ma, belongs to Homo antecessor, the earliest known European hominin species. The metatarsal exhibits a proliferative lesion on its medial periosteal surface. Periosteal reaction can be the bone response to a wide number of injurious processes. We describe a lesion on the basis of macroscopic and microscopic analyses, including microtomography and scanning electron microscopy. Externally, the osteoblastic lesion presents a highly porotic and disorganised morphology. Internally, we observe a series of micro‐fractures on the compact bone that do not affect the medullary canal. We provide a differential diagnosis and suggest that the ATD6‐124 lesion could correspond to a pedal stress fracture, also known as fatigue or march fracture. Stress fractures have been related to a load increase and muscular fatigue. This type of fracture has been widely reported in the foot of soldiers and athletes, which are usually engaged in strenuous, excessive or prolonged locomotive activities. Despite its high frequency in these groups, stress fractures have not been reported as such in fossil collections, with the exception of a metatarsal belonging to the Sima de los Huesos site (Atapuerca). Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
4.
In 1957, a new discovery inside Temple XVIII‐A was made in Palenque, the Mayan archaeological site in Chiapas Mexico, a royal tomb of an original design which proved to be the oldest at the site. Two skeletons were found, the principal (PAL‐44) was at the centre showing red pigmentation on the surface of some bones, personal adornments and offerings, which indicate that he was an early ruler of Palenque. The second (PAL‐45), deposited at the entrance, not in a special mortuary position, without offerings, suggests it was of a lower social status. This research presents a new bioarchaeological analysis with the following results: (i) The result of a direct radiocarbon dating of PAL‐44 by accelerator mass spectrometry is 250–420 cal AD (LTL12759A:1696 ± 30 BP). This means that the personage was buried long before the first designated ruler of Palenque, who, according to the epigraphic record was enthroned in ad 431. (ii) With X‐Ray Fluorescence, the red pigment was identified as cinnabar (HgS). (iii) PAL‐44 is a young adult male with a severe idiopathic scoliosis with a double curvature that affected the ribcage and lower limbs. Such a three‐dimensional deformity resulted in changes to his body mechanics and induced motion asymmetry. Consequently, his health and mobility must have been significantly affected by such a severe condition. (iv) PAL‐45 is an adult female with signs of nutritional problems in childhood and entheseal changes probably related to her activity. Three ante‐mortem traumas are registered: rib fracture, frontal depressed circular fracture and a nasal septal deviation. This traumatic event took place two weeks, approximately, prior to PAL‐45's death. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
5.
Legalized trauma     
In the past, criminals were executed by a variety of means, including beheading or hanging, and both these methods may leave signs on the skeleton. It is not difficult to recognize individuals who have been beheaded because one or other of the cervical vertebrae will show evidence of the fatal blow, and there may also be cut marks on the base of the skull or the back of the mandible. Death from hanging, however, often leaves no marks on the skeleton, especially when carried out with a running noose and no drop. With a drop, dislocation of the sutures at the base of the skull may be noted and the classic ‘hangman's fracture’, which is a fracture dislocation of the second cervical vertebra, may be present. When there is no evidence of trauma, death from hanging may have to be inferred in skeletons which are found with the hands tied or with other signs that are discussed here.  相似文献   
6.
This paper presents some of the basic principles of bone fracture physics and outlines characteristics used by forensic anthropologists to distinguish gunshot trauma from blunt trauma. The fracture pattern of a cranium from a historic cemetery in Memphis, Tennessee provides an example of how the mechanism of trauma could be misinterpreted. The pattern of the perimortem fractures is indicative of gunshot trauma with a bullet entering one side of the vault and impacting the opposite side. Identification of radiating fractures, concentric heaving fractures, and observation of the direction of bevel on the fractured surfaces are essential for interpretation of the mechanism that produced the injury.  相似文献   
7.
Prehistoric images are particularly versatile and difficult to grasp. In a few cases of historical continuity, local cultural glosses provide researchers with a rich corpus of data and help in the interpretation of the imagery. Such approaches contribute to the interpretation of the material in a frozen time perspective. Their impact on the development of archaeological methodologies enabling researchers to deal with strictly prehistoric image making traditions without any known descendant communities remains to be felt. This paper is an attempt to develop a subtle and robust archaeological methodology for the study of prehistoric images. The suggested approaches are replicable, and conclusions are falsifiable.Les images préhistoriques sont particulièrement versatiles, et leur sens difficile à cerner en raison de leur polysémie. Dans une poignée de cas, là ou il y a continuité historique, les chercheurs ont reussi à constituer une riche documentation sur les pratiques culturelles liées à l'utilisation des images. Ils/elles parviennent ainsi à des niveaux d'interpretation très detaillée, dans une conception paradoxalement réifiée des sociétés en question, conservant des pratiques culturelles inchangées pendant des millénaires. L'impact de telles approches sur l'élaboration de bonnes méthodes archéologique est négligeable. Dans la plupart des cas, les images et les vestiges matériels sont le uniques témoins des sociétés préhistoriques étudiées. Cet article s'efforce de developper des méthodes, à la fois subtiles et robustes, permettant une analyse systématique des images préhistoriques. Les méthodes proposées sont réplicables, et les conclusions refutables.  相似文献   
8.
This paper examines the rock art of the nyau secret society of eastern Zambia and central Malai. The art dates principally from the nineteenth and early twentieth centuries. It has been known to researchers since the 1970s but has given up few of its secrets. I examine the questions of why the art was made and why the tradition ceased. Key to answering these is the realization that the art belonged to a specific historical and geographic context: the era and area where nyau was forced to become an underground movement because of its suppression by Ngoni invaders, missions, and the later colonial government. The art provides us with detailed insights into the way nyau has served in the process of overcoming and manipulating the traumatic social changes faced by Chea society in the last few centuries.Cet article examine l'art rupestre de la société secrète de nyau au est du Zambia et Malai centrale. L'art date principalement aux dix-neuvième et bas vingtième siècles. Recherchers ont su l'art depuis les années soixante-dix, mais ils ont appris peu de ses secrets. J'examine les questions de pourquoi l'art était fabriquer et pourquoi la tradition a cessé. Pour résoudre ces questions c'est important à réaliser que l'art était à sa place dans un milieu spécifique d'histoire et géographie: au temps et place où nyau était forcer à devenir un mouvement clandestin à cause de sa répression par les envahisseurs Ngoni, les missions et, plus tard, le gouvernement colonial. L'art nous donne les aperçus détaillé sur comment nyau a servi dans le procès à surmonter et manipuler les changements traumatiques que la société Chea a bravé dans les siècles récents.  相似文献   
9.
Mauermanshoek Shelter, in the Korannaberg of the eastern Free State, has traditional San hunter–gatherer rock art together with white finger-painted horsemen of uncertain authorship. The excavated material dates to between 3500 bp and approximately 200 bp. The lithic assemblages show little change throughout, but ceramics, glass beads, and domesticated animal remains appear in the uppermost levels. The issue of most interest is that of the shelter's occupancy in the last few hundred years. Historical records show that the ethnic composition of the eastern Free State was complex during this time and that there were both aggressive and cooperative interactions between the various groups. Kora pastoralists were notorious stock raiders and the secure identification of other people on the landscape was complicated by a tendency for early writers to call all raiders Kora. A combination of archaeological and historical evidence suggests that San occupied the shelter for most of its history but that Kora herders may have been responsible for the finger-painted horsemen somewhere between 1837 and 1851 when a Wesleyan Mission Station, Merumetsu, served the Kora of Korannaberg.La grotte de Mauermanshoek, située dans le Korannaberg, à l'est de la province du Free State, contient des peintres rupestres de tradition San, réalisées par des chasseurs/bergers, ainsi que des cavaliers blancs, peint avec le doigt, d'une origine incertaine. Le matériel qu'on a trouvé dans les fouilles daté d'une période entre 3500 bp et approximativement 200 bp. L'industrie lithique est très homogène sur l'ensemble du site, mais des céramiques, des perles de verre et des restes d'animaux domestiques sont présents aux niveaux supérieurs. L'occupation de l'abri pendant les quelques centaines d'années passées est d'un inérêt tout particulier. Selon les archives historiques, la composition ethnique de la partie est du Free State était, à l'époque, complexe et il y avait les interactions à la fois agressifs et coopératifs entre les groupes différents. Les pasteurs Kora sont bien connus pour leur réputation d'attaquer les troupeaux mais l'identification certaine des autres peuplades est compliquée par le fait que les premiers écrivains rapportaient tous les aggresseurs comme des Kora. Une combinaison d'indices archeologiques et historiques suggère que les San occupèrent cette grotte pour la plus grande partie de son histoire mais que des bergers Kora pourraient être à l'origine des cavaliers peints avec le doigt, probablement entre 1837–1851, la période durant laquelle une mission Wesleyan servait le Kora de la région du Korannaberg.  相似文献   
10.
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