Micro-CT-assisted determination of the shattering and non-shattering phenotypes of charred rice spikelet bases from archaeological sites: a new methodological approach

The selection of a non-shattering phenotype is a pivotal change in the process of rice domestication. However, current research is heavily restricted by the preservation conditions of macro-plant remains in early and middle Neolithic sites, as very limited well-preserved rice spikelet bases could be retrieved. We present a non-destructive method based on micro-computed tomographic (CT) scanning, which could provide detailed visualization of the internal structures of charred spikelet bases and efficiently discriminate the shattering and non-shattering phenotypes of rice spikelet bases according to the abundance of fusiform echinate phytoliths. It could be widely applied in different contexts, especially those poorly preserved specimens and tempers in pottery sherds, greatly improving our knowledge of rice domestication.     

An Approach to the Diagnosis of Craniofacial Fibrous Dysplasia from the 2500‐Year‐Old Remains of a Skull from Ancient China

A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases.     

Experimental investigation of carbon dioxide trapping due to capillary retention in saline aquifers

Capillary trapping is a physical mechanism by which carbon dioxide (CO₂) is naturally immobilized in the pore spaces of aquifer rocks during geologic carbon sequestration operations, and thus a key aspect of estimating geologic storage potential. Here, we studied capillary trapping of supercritical carbon dioxide (scCO₂), and the effect of initial scCO₂ saturation and flow rate on the storage/trapping potential of Berea sandstone. We performed two‐phase, scCO₂‐brine displacements in two samples, each subject to four sequential drainage–imbibition core‐flooding cycles to quantify end‐point saturations of scCO₂ with the aid of micro‐ and macro‐computed tomography imaging. From these experiments, we found that between 51% and 75% of the initial CO₂ injected can be left behind after the brine injection. We also observed that the initial scCO₂ saturation influenced the residual scCO₂ saturation to a greater extent than the rate of brine injection under the experimental conditions examined. In spite of differences in the experimental conditions tested, as well as those reported in the literature, initial and residual saturations were found to follow a consistent relationship.     

Recycled Blessings: An Investigative Case Study of a Rewrapped Egyptian Votive Mummy Using Novel and Established 3D Imaging Techniques

This case study was the first of its kind, where neutron computed tomography (CT) was applied to a wrapped mummified animal. Conventional X‐ray CT was also used to allow for meaningful comparison, and complementary data for a comprehensive investigation. Previous applications of both techniques are limited to metallic objects, such as bronze Buddhas. The mummy used in this study (IA.2402) is dated between the Third Intermediate Period (1069–664 bce ) to Late Period (664–332 bce ) according to the wrapping style, and was originally believed to contain a complete skeleton of a feline. However, precise date and provenance were unknown. Our results prove the presence of only partial juvenile feline remains, and provide a date range for artefact creation (900–804 bce ± 30) and alteration (367–204 bce ± 30). Therefore, this study implements an established imaging technique (neutron CT) in a novel way, while preserving and conserving the intrinsic value of the artefact through non‐destructive investigation.     

基于电阻率成像法的莫高108窟墙体内水盐运移过程分析

非均质的砂砾石层是莫高窟壁画的主要墙体,但砂砾石层的非均质性如何在水盐运移过程中发挥作用却还不清楚。为此,通过在108窟西壁面上1 m×1 m和2 m×2 m范围的三维高密度电阻率成像监测,发现在这些区域上,墙体电阻率的空间分布都是非均匀的,低阻值区域在空间位置、大小和形状上都会随时间而变化。这明确说明在构成墙体的非均质砂砾石层内存在着重要的水分饱和与非饱和过程(再分配过程),正是这一不断重复的饱和与非饱和过程促进了墙体内水分的运移和盐分在一些特定区域的聚集。研究成果对全面认识莫高窟墙体内的水盐运移机理,减轻和防治壁画盐害都具有重要意义。     

First Trials to Set Up a Microwave Reflectometric Tool for the Survey of Historic Timber Structures

Timber structures can be degraded during their life both by structural problems and by biological degradation factors like fungi and insects. The occurrence of those biodegradation agents could lead to a loss of their structural integrity, in the absence of appropriate maintenance. An early assessment of the decay is even more important when the wooden structures are part of historical buildings, in the interest of conservation of cultural heritage.

This article presents an application of microwave reflectometry for the in situ evaluation of timber structures. The measurement system allows detecting anomalies inside the material in a non-destructive and non-invasive manner.

The reflection coefficient is measured by means of a vector network analyzer (VNA) using a double-ridge antenna which transmits the continuous-wave (CW) microwave signal and receives the signal reflected by the material under investigation.

Measurements on laboratory models demonstrated the feasibility of the method. Results obtained on timber beam sections, compared with the findings of traditional investigation methodologies, demonstrate the potentiality of microwave reflectometry, suggesting its possible usefulness during the diagnostic phase as a non-invasive tool for preliminary screening.     

Bone density studies in zooarchaeology

Accurate bone density data are essential for assessing the influence of destructive processes in archaeological faunal assemblages. Unfortunately, the diversity of methods employed by different researchers to derive density values has resulted in recent confusion. Two recent publications in this journal [J Archaeol Sci 29 (2002) 883; J Archaeol Sci 29 (2002) 979] exemplify this state of misunderstanding. Both studies argued that the role of bone density in shaping archaeological faunal assemblages has been largely overrated, but both based their conclusions on density values that were inaccurately derived. The former employed a method of calculating bone density that has been largely discredited over the past decade [J Archaeol Sci 29 (2002) 883]. Within a larger discussion of zooarchaeological methodology, the latter provided an assessment of the current state of bone density research that inappropriately characterized the discrepancies between available sets of density data as a reflection of the differences between two technologies—photon densitometry and computed tomography [J Archaeol Sci 29 (2002) 979]. The actual dichotomy exists—irrespective of the technology employed—between studies that account for variation in the shape of bone cross-sections and those that do not. The different sets of density data currently available to zooarchaeologists vary tremendously in their accuracy. We review and evaluate the different techniques employed in the research of bone density patterns of mammalian fauna. Computed tomography produces the most accurate density data. For elements without medullary cavities, photon densitometry may provide density values of similar accuracy but only if a method of cross-sectional shape-adjustment is applied.     

Joint geophysical measurements to investigate the Rossano of Vaglio archaeological site (Basilicata Region,Southern Italy)

A high resolution geophysical survey was carried out in the archaeological site of Rossano di Vaglio (Basilicata Region, Southern Italy), where an important ancient sanctuary is located. It was built during the IV century B.C. and devoted to the goddess Mephitis. The sanctuary rises in an area affected by a multiple and retrogressive rototraslational landslide, historically and presently subject to reactivation. The main objective of this work was the identification of buried structures of archaeological interest in an area designated by the Archaeological Superintendence of the Basilicata Region. The study was performed by means of the use of high resolution geophysical surveys. In particular, we made use of the joint application of three highly sensitive and non-invasive geophysical techniques, namely the Geoelectrical, the Magnetic and the Ground Probing Radar (GPR) methodologies. In such a way, we obtained two important results: first, we provided the archaeologists with information about the limits of the areas to be excavated; second, we could verify in real time the reliability of the geophysical results. The experimental results showed four main magnetic anomalies in the area of study, in agreement with the GPR results obtained for the same target. Finally, a partial excavation test of the investigated area revealed a buried building structure, located in correspondence of an anomaly identified by means of the geophysical prospecting.     

Integrating pedological and geophysical methods to enhance the informative value of an archaeological prospection – The example of a Roman villa rustica near Regensburg,Germany

Geophysical prospection techniques are widely used to visualize the buried past. Various methods such as magnetometry, electric resistance mapping and electric resistivity tomography and ground penetrating radar yield different results. The use of all three techniques in combination with aerial photography interpretation and pedological mapping is highly effective, but it requires a multi-layer approach. This paper presents such a multi-layer approach carried out at a site with buried remnants of a Roman villa rustica in southern Germany. The integration of the various results into a geographical information system leads to a geocodation of all outcomes and a final archaeological interpretation. Several buildings in different states of preservation, different kinds of ground floors both with and without hypocausts, perimeter walls and kilns could all be detected. The soil mapping results helped in the geophysical interpretation by outsourcing soil erosion and accumulation areas. It is shown that none of the employed methods could have supplied all the compiled information on their own, and the strengths and weaknesses of each method is discussed in order to point out the implications for archaeologists.