Characteristics of Bifacial-Reduction Flake-Size Distribution

1990 ◽  
Vol 55 (3) ◽  
pp. 550-558 ◽  
Author(s):  
Leland W. Patterson
Keyword(s):  
Detailed Analysis ◽  
Size Distribution ◽  
Archaeological Sites

Bifacial-reduction experiments suggest that the characteristics of flake-size distribution can be employed to detect bifacial-reduction activities at archaeological sites. However, data on bifaces in various stages of completion as well as on by-product flakes are necessary for detailed analysis of the biface-manufacturing sequence.

scholarly journals Insect Marks on Bones from La Guillerma Archaeological Locality (Salado River Depression, Buenos Aires, Argentina)

Quaternary ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 45
Author(s):  
Paula D. Escosteguy ◽  
Alejandro E. Fernandez ◽  
María Isabel González
Keyword(s):  
Detailed Analysis ◽  
Buenos Aires ◽  
Total Sample ◽  
Archaeological Sites ◽  
Buenos Aires Province ◽  
Faunal Remains ◽  
Faunal Assemblage ◽  
Different Types ◽  
Salado River ◽  
Bone Remains

The La Guillerma archaeological locality is located in the northeast sector of Buenos Aires province (Argentina). Two of its sites (LG1 and LG5), dated between ca. 1400- and 600-years BP, have a great amount of faunal remains including deer, rodents, fish and small birds that are subjected to taphonomic agents and processes (e.g., weathering, manganese, roots). Previous studies have shown osteophagic behaviour in different insects (e.g., Coleoptera, Blattodea). In this paper, we evaluate their incidence on La Guillerma faunal assemblage. We performed an analysis on marks that were identified in bone remains of various taxa and applied the criteria for identifying bone alteration by insects (i.e., by measuring each trace and comparing them with the types of insect marks described in the literature). Fifteen specimens (LG1 = 6 and LG5 = 9) exhibited different types of modifications (e.g., pits with striae in base, pits with emanating striae, striations) that are related to the action of insects. Although the proportion of affected bones is low in relation to the total sample, we highlight our study as the first detailed analysis of insect marks on archaeological bones from Argentina. We also emphasize the significance of addressing insect-produced modifications on Argentinean archaeological sites.

Cycles of change in Jomon settlement: a case study from eastern Tokyo Bay

Antiquity ◽  
2013 ◽  
Vol 87 (338) ◽  
pp. 1169-1181 ◽  
Author(s):  
Enrico R. Crema
Keyword(s):  
Detailed Analysis ◽  
Settlement Patterns ◽  
Tokyo Bay ◽  
Archaeological Sites ◽  
The North ◽  
Large Numbers ◽  
Regular Cycle ◽  
Residential Units ◽  
North Eastern

Japanese archaeology benefits from the large number of rescue excavations conducted during recent decades that have led to an unparalleled record of archaeological sites. That record is here put to use to interrogate changing settlement patterns in the north-eastern corner of Tokyo Bay during several millennia of the Jomon period (Early, Middle and Late Jomon: 7000–3220 cal BP). Jomon hunter-gatherer occupation is characterised by large numbers of settlements, some of them substantial in size, containing hundreds of individual pit-house residential units. Detailed analysis of the rank-size distribution of these settlements reveals a pattern in which periods of settlement clumping, with few large settlements, alternate with more dispersed settlement patterns on a regular cycle of approximately 600 years. The regularity of this cycle might suggest a correlation with cycles of climatic change, such as Bond events. Closer scrutiny shows, however, that such a correlation is unconvincing and suggests that cyclical change in Jomon settlement patterns may instead be due to other factors.

scholarly journals Mortars and plasters - How to characterize mortar and plaster degradation

2021 ◽  
Vol 13 (10) ◽  
Author(s):  
Mauro Francesco La Russa ◽  
Silvestro Antonio Ruffolo
Keyword(s):  
Detailed Analysis ◽  
Deep Understanding ◽  
Research Purpose ◽  
Archaeological Sites ◽  
Degradation Mechanisms ◽  
Built Heritage ◽  
Essential Tool ◽  
Conservation Plan ◽  
Set Up

AbstractThe degradation of mortars and plasters can represent a threat for their preservation. That is why a deep understanding of the degradation mechanisms and the identification of degradation patterns is strongly recommended for who is in charge of conservation of archaeological sites and of built heritage in general. Here, it has been described what are the main degrading agents that can be detected on mortars and plasters and how they act to produce degradation. Moreover, an overview of the analyses which can be carried out directly on site and in laboratory as well has been reported. The knowledge that can be achieved by using such methods represents an essential tool to set up a suitable conservation plan. In addition, a more detailed analysis can also have a research purpose, since they can be useful to clarify some mechanisms and interactions that still remain unclear.

The extinction time of a general birth and death process with catastrophes

1986 ◽  
Vol 23 (04) ◽  
pp. 851-858 ◽  
Author(s):  
P. J. Brockwell
Keyword(s):  
Laplace Transform ◽  
Size Distribution ◽  
Sufficient Conditions ◽  
Necessary And Sufficient Conditions ◽  
Death Process ◽  
Extinction Time ◽  
Birth And Death Process ◽  
Different Types ◽  
The Laplace Transform ◽  
Necessary And Sufficient

The Laplace transform of the extinction time is determined for a general birth and death process with arbitrary catastrophe rate and catastrophe size distribution. It is assumed only that the birth rates satisfyλ0= 0,λj> 0 for eachj> 0, and. Necessary and sufficient conditions for certain extinction of the population are derived. The results are applied to the linear birth and death process (λj=jλ, µj=jμ) with catastrophes of several different types.

Macrostructure and microphysics of Saturn's E-ring

1984 ◽  
Vol 75 ◽  
pp. 607-613 ◽  
Author(s):  
Kevin D. Pang ◽  
Charles C. Voge ◽  
Jack W. Rhoads
Keyword(s):  
Size Distribution ◽  
Spherical Shape ◽  
Mie Scattering ◽  
Narrow Size Distribution ◽  
Electrostatic Levitation ◽  
Volcanic Origin ◽  
Micron Diameter

Abstract.All observed optical and infrared properties of Saturn's E-ring can be explained in terms of Mie scattering by a narrow size distribution of ice spheres of 2 - 2.5 micron diameter. The spherical shape of the ring particles and their narrow size distribution imply a molten (possibly volcanic) origin on Enceladus. The E-ring consists of many layers, possibly stratified by electrostatic levitation.

Grain Refinement in Titanium-Erbium Alloys

1974 ◽  
Vol 32 ◽  
pp. 522-523
Author(s):  
B. B. Rath ◽  
J. E. O'Neal ◽  
R. J. Lederich
Keyword(s):  
Electron Microscopy ◽  
Size Distribution ◽  
Grain Refinement ◽  
Grain Growth ◽  
Volume Fraction ◽  
Pure Titanium ◽  
Systematic Investigation ◽  
Second Phase ◽  
Titanium Matrix ◽  
Average Size

Addition of small amounts of erbium has a profound effect on recrystallization and grain growth in titanium. Erbium, because of its negligible solubility in titanium, precipitates in the titanium matrix as a finely dispersed second phase. The presence of this phase, depending on its average size, distribution, and volume fraction in titanium, strongly inhibits the migration of grain boundaries during recrystallization and grain growth, and thus produces ultimate grains of sub-micrometer dimensions. A systematic investigation has been conducted to study the isothermal grain growth in electrolytically pure titanium and titanium-erbium alloys (Er concentration ranging from 0-0.3 at.%) over the temperature range of 450 to 850°C by electron microscopy.

Formation and Structure of Casein Micelles in Lactating Mammary Tissue

1970 ◽  
Vol 28 ◽  
pp. 150-151
Author(s):  
Robert J. Carroll ◽  
Marvin P. Thompson ◽  
Harold M. Farrell
Keyword(s):  
Size Distribution ◽  
G Protein ◽  
Milk Proteins ◽  
Mammary Tissue ◽  
Colloidal System ◽  
Casein Micelles ◽  
The Stability

Milk is an unusually stable colloidal system; the stability of this system is due primarily to the formation of micelles by the major milk proteins, the caseins. Numerous models for the structure of casein micelles have been proposed; these models have been formulated on the basis of in vitro studies. Synthetic casein micelles (i.e., those formed by mixing the purified αsl- and k-caseins with Ca2+ in appropriate ratios) are dissimilar to those from freshly-drawn milks in (i) size distribution, (ii) ratio of Ca/P, and (iii) solvation (g. water/g. protein). Evidently, in vivo organization of the caseins into the micellar form occurs in-a manner which is not identical to the in vitro mode of formation.

The use of scanning electron microscopy in interpreting chenopodium remains from three archaeological sites in northwestern Iowa

1992 ◽  
Vol 50 (2) ◽  
pp. 1112-1113
Author(s):  
Douglas William Jones
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Archaeological Sites ◽  
Late Prehistoric ◽  
Eastern United States ◽  
Chenopodium Berlandieri ◽  
Seed Identification ◽  
Level 2 ◽  
Scanning Electron

Within the past 20 years, archaeobotanical research in the Eastern United States has documented an early agricultural complex before the dominance of the Mesoamerican domesticates (corn, beans, and squash) in late prehistoric and historic agricultural systems. This early agricultural complex consisted of domesticated plants such as Iva annua var.macrocarpa (Sumpweed or Marshelder), Hellanthus annuus (Sunflower) and Chenopodium berlandieri, (Goosefoot or Lasbsquarters), and heavily utilized plants such as Polygonum erectum (Erect Knotweed), Phalaris caroliniana (May grass), and Hordeum pusillum (Little Barley).Recent research involving the use of Scanning Electron Microscopy (SEM) specifically on Chenopodium has established diagnostic traits of wild and domesticated species seeds. This is important because carbonized or uncarbonized seeds are the most commonly recovered Chenopodium material from archaeological sites. The diagnostic seed traits assist archaeobotanists in identification of Chenopodium remains and provide a basis for evaluation of Chenopodium utilization in a culture's subsistence patterns. With the aid of SEM, an analysis of Chenopodium remains from three Late Prehistoric sites in Northwest Iowa (Blood Run [Oneota culture], Brewster [Mill Creek culture], and Chan-Ya-Ta [Mill Creek culture]) has been conducted to: 1) attempt seed identification to a species level, 2) evaluate the traits of the seeds for classification as either wild or domesticated, and 3) evaluate the role of Chenopodium utilization in both the Oneota and Mill Creek cultures.

Preparation And elemental analysis of ancient fibers

1987 ◽  
Vol 45 ◽  
pp. 410-411
Author(s):  
Allen Angel ◽  
Kathryn A. Jakes
Keyword(s):  
Cross Sections ◽  
Physical Structure ◽  
Energy Dispersive ◽  
Archaeological Sites ◽  
X Ray ◽  
Long Term Storage ◽  
Backscattered Electron ◽  
Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

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