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1.
This paper focuses in the morphometric analyses of Lama guanicoe remains recovered from the hunter–gatherer archaeological site Alero Deodoro Roca, located at Sierras Pampeanas Australes region (Córdoba Argentina), an area that has little information on the body‐size variability of these artiodactyls. Because of the sparse osteometric data in the region, we focused on determining inter‐intraspecific differentiation of wild camelids through corroborated osteometric techniques and multivariate statistical analyses of proximal phalanges. Our results showed a clear interspecific differentiation between modern vicuñas and archaeological specimens. We could also distinguish at least three guanaco size groups (small, medium and large) with the archaeological remains from the late Holocene (3000–3600 bp ) of the site, presenting medium‐size characteristics. Finally this paper aims at establishing a first approach in the characterisation of guanaco body size in the mountainous region of Córdoba. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

2.
The distribution of marmots in the Soviet Union has been mapped at three general scales: particular maps, showing colonies and burrows in small landscape units; regional maps, using medium scales, and general maps, at small scales, showing the entire Soviet Union.  相似文献   

3.
泗阳汉墓埋藏环境中细菌的分析与检测   总被引:1,自引:0,他引:1  
木质物在埋藏环境中不可避免地会受到细菌的侵害,细菌可以对木材的化学成分及超微结构造成很大的影响。本研究采用羧甲基纤维素钠(CMC)改良培养基平板法对泗阳汉墓埋藏环境中的土样及木样中的好氧纤维素分解菌、厌氧纤维素分解菌进行了筛选和纯化;采用CMC培养基平板稀释法对纤维素分解菌数量进行了测定;采用牛肉膏蛋白胨培养基法对优势菌株进行活化,并对其中的16株进行了鉴定。鉴定结果表明泗阳汉墓中的细菌种类主要有奥斯陆莫拉菌、丁香假单胞菌、自养水螺菌、肠杆菌属、魔芋食酸菌、过滤弧菌、假单胞菌等。细胞的形态主要有短杆、球形、杆状等。研究埋藏环境中土样及木样中细菌的种类、数量、分布等可以对木材的劣化机理研究提供科学的分析,为今后的物保护工作提供理论和实践上的指导。  相似文献   

4.
During the years 1981–1989, 71 solar proton events altogether were observed. Dividing the events into strong, p.f.u. > 1000 (p.f.u.—proton flux measured at geosynchronous satellite orbit in units of (cm2 s sr)−1), medium, 100 < p.f.u. < 1000 and weak events, p.f.u. < 100, only the strong and medium events have a considerable effect on the lower ionosphere. The mean daily absorption at 30 MHz (A), measured in the auroral zone, is >2 dB during strong events, <2 dB during medium events and < l dB during weak events. The most active year during the EISCAT operation was 1989 when 23 solar proton events were observed including six strong events. Diurnal variation of the electron density in the D-region during PCA is a function of the solar zenith angle. However, south of L = 5 a minimum in absorption is observed during the noon hours. During sunrise the absorption increases simultaneously with solar elevation angle, but during sunset there is about 2 h delay between the decrease of absorption and the solar elevation angle.  相似文献   

5.
Recent literature reviews on contributions applying the multiple streams framework (MSF) concluded that although the framework is prolific, there is a lack of contributions testing it in a larger sample size. By addressing which barriers to entry medium and large n MSF applications face and by suggesting ways to handle them, we aim at providing researchers with a benchmark contribution for developing MSF‐guided research designs based on a medium to a high number of cases. Building on an overview of the few existing medium and large n MSF studies, we address three challenges researchers must deal with: (1) choice of dependent variables and case selection; (2) operationalization and measurement of the framework's (predominantly figurative) key concepts; and (3) choice of a method that corresponds with the framework's research questions. In the latter regard, we focus on the pros and cons of employing regression analysis and qualitative comparative analysis. We conclude that although the barriers to entry are high for testing the MSF in a larger sample size, they are not insurmountable.  相似文献   

6.
The OSL, post-IR OSL and pulsed post-IR OSL applied to polymineral grains and calculated by fitting to the data the contributions from fast, medium and slow components revealed that the polymineral samples under study are dominated by the medium component. An increase in D e ’s with increasing integration intervals was observed, which is considered as an indication of increasing medium and decayed fast component; and the equivalent doses obtained using different components or minerals reflect also the shape of the dose distributions. The identified fast component in polymineral sample has photoionization cross section of 1.2±0.02 × 10?17 cm2. The present study shows the usefulness of the application of different luminescence techniques combined with fitting procedures as a check which should be adopted in dating protocols. Based on luminescence ages obtained on poly-mineral grains from prehistoric pottery samples from the Boroo settlement, Mongolia, which are in agreement with independent age control by 14C on charcoal material, it is argued that the manufacturing of Xiongnu — pottery at this site lasted until ca. 130±75 AD.  相似文献   

7.
The determination of the kinematic parameters of travelling ionospheric disturbances (TIDs) is an essential basis for their physical understanding and investigation of their possible excitation mechanisms. This paper describes a method to determine these parameters on the basis of combined radio interferometric observations and measurements of differential Doppler shift observed for NNSS satellites.The analysis of Dutch interferometric and differential Doppler observations, based on this method, shows that the average direction of propagation of a sample of medium scale TIDs observed during the first three months of 1982 and 1983 is towards about 10° west of south; the speeds and horizontal ‘wavelengths’ are typical for medium scale TIDs. The results are in satisfactory agreement with those of similar research performed at Nançay (France) more than 4 yr later and using a different methodology, but not with results obtained at Nançay during the same winter months as used in the present study. Differences may indicate that TID parameters vary with geographic location and time.  相似文献   

8.
The detection of trace binding medium in wall paintings is usually challenging due to the aging and degradation of proteinaceous binding medium in a long time. Therefore, immunomagnetic beads (IMBs) with specific enrichment ability for casein and ovalbumin were prepared, and then the beads were applied for capturing target proteinaceous binding medium from ancient Chinese wall paintings. After optimization of experimental conditions, the enrichment performance of magnetic beads was confirmed by enzyme-linked immunosorbent assay (ELISA) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). In this experiment, archaeological wall painting samples were used to verify the accuracy of the construction enrichment method. The results showed that the OD450nm value of archaeological samples containing binding medium has increased to varying degrees after IMBs enrichment, effectively avoiding the occurrence of false negative results, indicating that the IMBs enrichment method developed in this work could be successfully applied for enriching ovalbumin and casein binding medium from ancient wall paintings for subsequently immunoassay detection.  相似文献   

9.
陶寺中期墓地被盗墓葬抢救性发掘纪要   总被引:1,自引:0,他引:1  
2005年3月~6月,陶寺遗址6座中小型墓葬经抢救性发掘,出土了一批陶器、玉石器和一件铜器。经初步研究,其年代为陶寺文化中期。  相似文献   

10.
Wool fibre measurements defining fleece type are described from cloth remains found in the seventeenth century wreck of the Wasa in Stockholm harbour. Half the fleeces were from the primitive type known as the hairy medium, and the remainder were distributed over the hairy, generalized medium and medium types, with a few short and fine types. The wools were similar to medieval Swedish wools, being coarser than Viking examples, but finer than the fleeces of living, primitive Swedish Goth breed.  相似文献   

11.
Wool fibre measurements are described from four unconnected remains: (1) some possibly Iron Age sheepskin from Germany that appeared to have a hairy fleece type; (2) the cloth from the Quernmore burial, Lancashire (dated 1300 years BP), one yarn of which was of hairy medium type, and the other true medium; (3) some sheepskin from Saxon Durham which had wool of true medium type, and (4) some wool of medieval date from Baynard's Castle, London, which was of true fine type.  相似文献   

12.
The incidence of endemic goiter in southeast Kazakhstan, a highly goitrogenic province of the Soviet Union, is related to the geochemical setting of the region's natural areal complexes. The occurrence of endemic goiter is usually attributed simply to iodine deficiency. However other chemical elements also tend to reduce or enhance the goitrogenic properties of a particular environment. A detailed analysis of the various environments in southeast Kazakhstan shows that not all parts of the region are equally goitrogenic and that high, medium and low risk areas may be distinguished. The various natural areal complexes of different levels of goitrogenicity are mapped together with actually observed incidence of the disease. It is recommended that public health activities, such as the provision of iodized salt, be directed in particular at the high and medium risk areas.  相似文献   

13.
The characteristics of medium scale travelling ionospheric disturbances (MSTIDS) have been determined from observations carried out between 1972 and 1975 at Leicester U.K. (52°32′N, 1°8′W) using the HF Doppler technique. By reverse ray tracing through a model atmosphere an estimate of the source locations of these waves can be obtained. Auroral sources do not appear to represent an important generation mechanism for MSTIDs observed at mid-latitudes. The majority of waves originate at tropospheric altitudes at ground ranges of less than 1500 km from the observation point, and a moderate correlation is found between the occurrence frequency of MSTIDs and the intensity of the meteorological jet stream.  相似文献   

14.
This review examines models existing in the literature which describe the magnetic field produced by the ring current (DR) at the Earth's surface based on the energy balance equation. The parameters of this equation, the injection function F and decay parameter τ are considered to depend on parameters of the interplanetary medium and the DR intensity. The existing models are shown to be able to describe the DR variations with sufficient accuracy (r.m.s. deviation δ between the experimental and modelled values of DR for 170 magnetic storms is 5 < δ < 15 nT and the correlation coefficient between the two is 0.85 <r<1). The models describe that part of the geomagnetic field variation at low latitudes during a magnetic storm that is controlled by the geoeffective characteristics of the interplanetary medium and which thus responds immediately to its variations (the driven part).The values of τ are significantly less during the main phase of a magnetic storm than during the recovery phase. This reflects the difference in the main mechanisms of ion loss from the ring current during the two phases of the storm. These are the interaction of ions with hydromagnetic waves during the main phase of the storm with its intervals of intense plasma injection into the inner magnetosphere and charge exchange with the cold hydrogen geocorona during the recovery phase.  相似文献   

15.
Summary. Eight carpet or textile yarns and six felt samples from the frozen burials dated c. 400 B. C. at Pazyryk and Bashadar were studied. One sample was identified as underwool from a non-fleeced 'hair' sheep (Neolithic survival). Five samples were of the most primitive fleece type, the hairy medium wool, and five of the next most primitive type, the generalised medium wool (both emerged in the Bronze Age). There was one hairy sheep and, as found at Hallstatt, there were two semi-fine fleeces (shortwools). The last two types developed in the Iron Age.  相似文献   

16.
Abstract

The mutilated remains of the choir furniture in this remote parish church disclose the evidence of a 14th-century double-credal decorative scheme. It is a unique British survival of this iconography in the medium. This paper analyses the monument in terms of patronage, style and dating, and recounts its remarkable afterlife. In attempting to place it within an English medieval credal context, it is apparent that, in any medium, such schemes are a rarity. As a result, possibly with one important exception, relating to the chapel glass at Hampton Court, Herefordshire, the subject has neither lent itself to the publication of a wide-ranging archaeological monograph, nor to an adequate discussion of the central importance of the creed and its visual expression in catholic Christian theology. As well as bringing to light the history and archaeology of the Astley programme, it was necessary to make amends by conducting a survey of medieval credal schemes in all media surviving in Europe, including the late-medieval Savoyard group of choir-stalls, with their carved-wood figures of prophets and apostles on the seat backs.  相似文献   

17.
This paper is concerned with the morphological evolution of three‐dimensional chemical dissolution fronts that occur in fluid‐saturated porous media. A fully coupled system between porosity, pore‐fluid flow and reactive chemical species transport is considered to describe this phenomenon. Using the newly presented concept of the generalized dimensionless pore fluid pressure‐gradient, which can be used to represent the interaction between solute advection, solute diffusion, chemical kinetics and the shape factor of the soluble mineral, a theoretical criterion has been established to assess the likelihood of instability at a chemical dissolution front in the reactive transport system. To simulate the chemical dissolution front evolution in a three‐dimensional fluid‐saturated porous medium, a numerical procedure combining both the finite difference method and the finite element method has been proposed. As the problem belongs to a complex system science problem, a small randomly generated perturbation of porosity is added to the initial porosity of a three‐dimensional homogeneous domain to trigger instability of a planar chemical dissolution front during its propagation within the fluid‐saturated porous medium. To test the correctness and accuracy of the proposed numerical procedure, a three‐dimensional benchmark problem has been constructed and the related analytical solution has been derived. This enables using the proposed numerical procedure for simulating the morphological evolution of a three‐dimensional chemical dissolution front from a stable, planar state into an unstable, fingering state. The related numerical results demonstrate that the proposed numerical procedure is useful for, and capable of, simulating the morphological instability of a three‐dimensional chemical dissolution front within a fluid‐saturated porous medium.  相似文献   

18.
This article argues against ‘microfinance narcissism’ and calls for a re‐politicization of the microfinance paradigm. The dominant verdict on microcredit has undergone a damning transformation, from ‘magic bullet for poverty reduction’ to ‘cause of suicide’. Nowadays, both radical critics and mainstream voices deplore microcredit's negative impact on micro‐entrepreneurs. They argue for a reorientation where credit is targeted at established small and medium‐sized enterprises, particularly in rural areas. The crisis in microfinance worldwide, including burgeoning protests, are viewed as proof of the commercial derailment and/or misplaced faith in microfinance's positive social and economic impact on the poor. This article engages with this debate through a study of the Nicaraguan micro‐finance crisis. It challenges existing analyses that pin the crisis on agricultural over‐indebtedness, lack of due diligence, or Sandinista populist politics. Illustrating the dangers of neglecting the diverse nature of microfinance, it reveals the paradoxical outcomes of the crisis: a refocus on the urban at the expense of agricultural credit for small and medium enterprises and a consolidation of the power of national processing elites. Nicaragua's Non‐Payment Movement is also shown to be both a product of elite manipulation and an expression of legitimate resistance to an industry that turns a blind eye to the manner in which markets and politics constrain clients’ potential.  相似文献   

19.
Examination of impressions from chaff-tempered mud brick proved rewarding, given the poor preservation of carbonised seed and grain material at Tell Abraq. Individual chaff elements were found to be recognisable from the impressions and it was shown that naked wheat and barley chaff were used as a tempering medium. Charcoal samples indicate that two species of mangrove were present, one of which is no longer found in the area. Tamarisk and Ziziphus were also present. Date charcoal was common. This study remains preliminary, and further sampling and analyses have been planned for the future.  相似文献   

20.
This article explores an argument on love as it was articulated within the framework of the ‘New Ethics’ sexual reform in Germany at the beginning of the twentieth century. While many commentaries on the alienating impact of modernity projected authenticity onto the ‘non‐modern’ woman and her love, the feminist authors at issue in this article promote ‘modern love’ as a medium of women's participation in modernity. Furthermore, they address the problem of love's temporality and non‐exclusivity. Yet, the engagement with these topics is a tricky one because non‐exclusivity and impermanence are at the same time dismissed as ‘decadent’ ways of loving and attributed to ‘archaic’ Europe and non‐European cultures.  相似文献   

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