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1.
In order to resolve long-standing issues surrounding the age of the Skhul early modern humans, new analyses have been conducted, including the dating of four well-provenanced fossils by ESR and U-series. If the Skhul burials took place within a relatively short time span, then the best age estimate lies between 100 and 135 ka. This result agrees very well with TL ages obtained from burnt flint of 119+/-18 ka (Mercier et al., 1993). However, we cannot exclude the possibility that the material associated with the Skhul IX burial is older than those of Skhul II and Skhul V. These and other recent age estimates suggest that the three burial sites, Skhul, Qafzeh and Tabun are broadly contemporaneous, falling within the time range of 100 to 130 ka. The presence of early representatives of both early modern humans and Neanderthals in the Levant during Marine Isotope Stage 5 inevitably complicates attempts at segregating these populations by date or archaeological association. Nevertheless, it does appear that the oldest known symbolic burials are those of early modern humans at Skhul and Qafzeh. This supports the view that, despite the associated Middle Palaeolithic technology, elements of modern human behaviour were represented at Skhul and Qafzeh prior to 100 ka.  相似文献   

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The Banyoles mandible presents a puzzle. Its anatomy has been described as pre-Neandertal, but the travertine in which it was found has been dated to 45,000 +/- 4000 years. By this time, any pre-Neandertals had supposedly been absent from the European fossil record for more than 100,000 years. It was therefore proposed that the age of the travertine may represent a minimum age estimate, with the mandible possibly having been reworked from older deposits. We carried out a non-destructive ESR analysis of an enamel fragment removed from a molar and performed a series of in situ laser ablation U-series analyses on dentine fragments adjacent to the enamel piece. The analyses resulted in an apparent combined ESR-U-series age of 66,000 +/- 7000 years. The encasing travertine matrix was also analyzed for U-series isotopes and showed signs of U-mobilization. It cannot be excluded that the travertine matrix is older than the previously determined age. If the mandible was not reworked, then the combined ESR-U-series result on the tooth enamel would give its best age estimate. If, on the other hand, the mandible was reworked from another deposit, the actual ESR-U-series age will depend on the external dose rate from the previous matrix and the depth of its burial, which controls the degree of the attenuation of the cosmic dose rate over time. Considering a range of possible burial histories, the mean age of the mandible would lie somewhere between the combined ESR-U-series age and the previously determined age of the travertine matrix. Regarding the morphology of the mandible, a review of its features in the context of larger Neandertal samples indicates that the anatomy of the specimen is not incompatible with such a young age determination, although it further highlights morphological variation in the late Neandertal sample.  相似文献   

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The Sierra de Atapuerca, northern Spain, is known from many prehistoric and palaeontological sites documenting human prehistory in Europe. Three major sites, Gran Dolina, Galería and Sima del Elefante, range in age from the oldest hominin of Western Europe dated to 1.1 to 1.3 Ma (millions of years ago) at Sima del Elefante to c.a. 0.2 Ma on the top of the Galería archaeological sequence. Recently, a chronology based on luminescence methods (Thermoluminescence [TL] and Infrared Stimulated Luminescence [IRSL]) applied to cave sediments was published for the Gran Dolina and Galería sites. The authors proposed for Galería an age of 450 ka (thousands of years ago) for the units lower GIII and GII, suggesting that the human occupation there is younger than the hominid remains of Sima de los Huesos (>530 ka) around 1 km away.  相似文献   

6.
描述了自中国安徽省发现的毛茛科唐松草属一新种,岳西唐松草Thalictrumyuexiense,并给出了其与近缘种尖叶唐松草的区别特征。  相似文献   

7.
Nucleotide sequences of the internal transcribed spacer 2 (ITS2) region were determined from seven adults of species Paragonimus collected from Jinde and Xiuning Counties, Anhui Province, China. Among these, the nucleotide sequence obtained from one Paragonimus adult (Jinde County) was identical to the ITS2 sequence of P. ohirai previously reported. In order to confirm the result, partial regions of mitochondrial cytochrome C oxidase I (COI) and NADH dehydrogenase 1 (ND1) from the putative P. ohirai sample were further sequenced. They showed a high level of similarity with those of P. ohirai, COI (99.7%) and ND1 (99.5%), supporting the result obtained from the ITS2. In addition to this, we designed P. ohirai- and P. westermani-specific primers (BDW and BD2OH) from ITS2 to identify P. westermani and P. ohirai easily and rapidly. After testing utility of the primers, they were applied to identify seven unidentified Paragonimus samples collected from Jinde and Xiuning Counties, China. All the examined samples showed P. westermani band pattern, and it was reconfirmed by sequencing their ITS2 regions that they are P. westermani. This result indicates that the two newly designed specific primers could be quite helpful for easily identifying P. westermani and P. ohirai, that most of Paragonimus in Jinde and Xiuning Counties consist of P. westermani, and that P. ohirai exists in Jinde County with minority.  相似文献   

8.
安徽苦草属—新种   总被引:3,自引:0,他引:3  
《植物分类学报》2001,39(6):571-574
描述了1个新种,即安徽苦草,并提供了该属全部已知国产种的分种检索表。  相似文献   

9.
安徽藓类植物区系   总被引:6,自引:0,他引:6  
作者在对安徽省进行实地考察和采集的2000余号苔藓植物标本的基础上,经过研究鉴定,并收集整理了有关安徽藓类的资料,对照现有文献,发现安徽已知藓类植物有46科、164属、545种(包括8亚种和32变种),其中新记录95种(包括3变种1亚种);青藓科为安徽省藓类第一大科,含9属52种,占总种数的9.6,青藓属是第一大属,包括有29种,占总种数5.3;科内种数(≥19种)优势科有10个,属内种数(≥6种)的优势属有22个。在安徽省藓类区系中,以东亚成分为主并占了28.6、北温带成分占23.0、热带亚洲成分占17.8,温带亚洲成分为10.6,中国特有成分占到10.4,这5种区系成分都超过10,它们是本省最主要的区系地理成分。  相似文献   

10.
描述了产于安徽境内的竹亚科刚竹属4个新种,即:糙竹、燥壳竹、广德芽竹、谷雨竹,并讨论了与近缘类群的区别,提供了显示鉴别特征的活植物及模式标本图片.新种的主模式标本均保存于安徽农业大学树木标本馆.  相似文献   

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桃花水母属Craspedacusta隶属于刺胞动物门Cnidaria水螅纲Hydrozoa淡水水母目Limnomedusae笠水母科Olindiidae。我国的桃花水母种类丰富,分布广泛,近年来多地有新种和分布新纪录的报道。安徽曾发现桃花水母,但均未进行详细描述和研究。本文对采自安徽省金寨县梅河河谷水潭内的桃花水母进行了初步研究,依据其伞形、缘膜宽度、触手及平衡囊数目、刺丝囊疣形状和排列方式、生殖腺形状和颜色等形态特征对其进行初步的分类鉴定。结果表明,此次在金寨县发现的桃花水母更接近于宜昌桃花水母Craspedacusta kawaii Oka,1907。这是对安徽省发现的桃花水母首次进行较为明确的分类鉴定和初步的形态学研究。  相似文献   

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High-precision U-series dating of Locality 1 at Zhoukoudian, China   总被引:6,自引:0,他引:6  
Thermal ionization mass spectrometric(230)Th/(234)U dating has been carried out on intercalated speleothem samples from the limestone cave occupied by Homo erectus at Zhoukoudian, China. The samples were recently collected in proper stratigraphic context after detailed field examinations. The results show that the age of the No. 5 Skull from Layer 3 is >400 ka, possibly in the range of about 400-500 ka, and that the hominid fossils from the lower strata are at least 600 ka and possibly >800 ka, much older than previously thought. The near-equilibrium(230)Th/(234)U ratios and internal consistency of the dates and stratigraphy lend credence to the results and allow us to comment on their important implications for human evolution.  相似文献   

13.
周平  李杨  魏伟  刘梅  王丽  孙庆业 《生物学杂志》2013,(6):26-31,35
通过对铜陵地区不同河段的上覆水和沉积物的理化性质进行分析,结合聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)的方法,研究了铜陵不同河段中附生细菌的多样性及其与环境因子的关系。结果表明,8个河段中上覆水和沉积物的营养水平及重金属含量存在较大差异,不同河段附生细菌的多样性指数也存在差异。数据分析表明,铜陵河流中黄浒河附生细菌的多样性最高,顺安河下游和钟仓河附生细菌的多样性最低。这种差异主要与河段间上覆水和沉积物不同的营养水平、重金属含量水平等因素有关。附生细菌的香农-威纳多样性与上覆水中的氨态氮(NH3-N)、总氮(TN)、总磷(TP)、可溶性正磷酸盐(PO3-4-P)和高锰酸盐指数(COD Mn)呈显著或极显著负相关,与沉积物中镉(Cd)、铜(Cu)和锌(Zn)的含量具有显著或极显著正相关性。  相似文献   

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The Yixian Formation of Liaoning Province, People's Republic of China has yielded a diverse fauna of non-avian dinosaurs, but is dominated by small-bodied taxa. Here, we describe a series of isolated teeth from the Lujiatun Beds of the formation that are referable to a basal titanosauriform sauropod. Some of the teeth possess a distinctive circular boss on the lingual surface, which suggests that they are referable to cf. Euhelopus sp. This identification provides some additional support for biostratigraphical correlations between the Jehol Group and the Mengyin Formation of Shandong Province that suggest an Early Cretaceous age for the latter unit. Moreover, the titanosauriform affinities of the teeth provide further evidence for the dominance of this sauropod clade in eastern Asia during the Cretaceous.  相似文献   

16.
In 1995-1996 two isolated hominin lower incisors were found at the middle Pleistocene site of Boxgrove in England, with Lower Palaeolithic archaeology. Boxgrove 2 is a permanent lower right central incisor and Boxgrove 3 a permanent lower left lateral incisor. They were found separately, but close to one another and appear to belong to the same individual. The Boxgrove 1 tibia discovered in 1993 came from a different stratigraphic context and is thus believed to represent a different individual. This paper describes the morphology of the incisors, which is similar to other middle Pleistocene hominin specimens and, as with the tibia, suggests that they could be assigned to Homo heidelbergensis (recognising that the taxonomic status of this species is still a matter of debate). The incisors show substantial attrition associated with secondary dentine deposition in the pulp chamber and clearly represent an adult. They also show extensive patterns of non-masticatory scratches on the labial surfaces of both crown and root, including some marks which may have been made postmortem. The roots were exposed in life on their labial sides by a large dehiscence, extending almost to the root apex. This is demonstrated by deposits of calculus, polishing, and scratching on the exposed surfaces. The dehiscence may have been caused by repeated trauma to the gingivae or remodelling of the tooth-supporting tissues in response to large forces applied to the front of the dentition.  相似文献   

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Background

Schistosomiasis japonica still remains of public health and economic significance in China, especially in the lake and marshland areas along the Yangtze River Basin, where the control of transmission has proven difficult. In the study, we investigated spatio-temporal variations of S. japonicum infection risk in Anhui Province and assessed the associations of the disease with key environmental factors with the aim of understanding the mechanism of the disease and seeking clues to effective and sustainable schistosomiasis control.

Methodology/Principal Findings

Infection data of schistosomiasis from annual conventional surveys were obtained at the village level in Anhui Province, China, from 2000 to 2010 and used in combination with environmental data. The spatio-temporal kriging model was used to assess how these environmental factors affected the spatio-temporal pattern of schistosomiasis risk. Our results suggested that seasonal variation of the normalized difference vegetation index (NDVI), seasonal variation of land surface temperature at daytime (LSTD), and distance to the Yangtze River were negatively significantly associated with risk of schistosomiasis. Predictive maps showed that schistosomiasis prevalence remained at a low level and schistosomiasis risk mainly evolved along the Yangtze River. Schistosomiasis risk also followed a focal spatial pattern, fluctuating temporally with a peak (the largest spatial extent) in 2005 and then contracting gradually but with a scattered distribution until 2010.

Conclusion

The fitted spatio-temporal kriging model can capture variations of schistosomiasis risk over space and time. Combined with techniques of geographic information system (GIS) and remote sensing (RS), this approach facilitates and enriches risk modeling of schistosomiasis, which in turn helps to identify prior areas for effective and sustainable control of schistosomiasis in Anhui Province and perhaps elsewhere in China.  相似文献   

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报道安徽省1个新记录科植物和2个新记录种植物:肠蕨科Diplaziopsidaceae川黔肠蕨Dipalziopsis cavaleriana(Christ)C Chr.、铁角蕨科Aspleniaceae黑边铁角蕨Asplenium speluncae Christ以及景天科Crassulaceae大苞景天Sedum amplibracteatum K.T.Fu。凭证标本均保存于安徽中医药大学标本馆(ACM)。  相似文献   

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