scholarly journals Six Decades of Radiocarbon Dating in New World Archaeology

Radiocarbon ◽  
2009 ◽  
Vol 51 (1) ◽  
pp. 173-212 ◽  
Author(s):  
R E Taylor

Radiocarbon (14C) dating provided New World archaeological research with the first continent-wide common chronometric scale that transcended the mostly relative site- and region-specific chronological sequences that had been assembled during the preceding century of fieldwork. 14C data continue to play a critical role in establishing a chronometric framework for the 5-century-long debate concerning the timing of the initial peopling of the New World. Other issues where 14C results have been of particular importance include the origins and development of New World agriculture and determination of the relationship between the Western and Classic Maya long-count calendar. The introduction of a third-generation measurement technology of accelerator mass spectrometry (AMS) beginning in the late 1970s has provided a means of obtaining analyses on milligram and microgram amounts of carbon permitting more detailed critical approaches to increasing the accuracy of 14C values on certain sample types—particularly human skeletal materials. It also provided a more effective means of allowing greater dating precision in situations where such data had an important bearing on the validity of inferences about the rates of cultural evolutionary change in New World societies.

Radiocarbon ◽  
2000 ◽  
Vol 42 (1) ◽  
pp. 1-21 ◽  
Author(s):  
R E Taylor

When introduced almost five decades ago, radiocarbon (14C) dating provided New World archaeologists with a common chronometric scale that transcended the countless site-specific and regional schemes that had been developed by four generations of field researchers employing a wide array of criteria for distinguishing relative chronological phases. A topic of long standing interest in New World studies where 14C values have played an especially critical role is the temporal framework for the initial peopling of the New World. Other important issues where 14C results have been of particular importance include the origins and development of New World agriculture and the determination of the relationship between the western and Mayan calendars. It has been suggested that the great success of 14C was an important factor in redirecting the focus of American archaeological scholarship in the 1960s from chronology building to theory building, led to a noticeable improvement in US archaeological field methods, and provided a major catalyst that moved American archaeologists increasingly to direct attention to analytical and statistical approaches in the manipulation and evaluation of archaeological data.


2018 ◽  
Vol 7 (2.26) ◽  
pp. 7
Author(s):  
K David ◽  
R Anand

You cannot control what you can’t measure - Tom DeMarco -Metrics plays a critical role in any industry. The metrics can tell the senior management the health of the activity in that organization. In the paper, we have studied the relationship between the metrics and the quality of deliverables. Once the right metrics are identified for a particular phasein the life cycle model it will help the project manager to proactive-ly detect the issues earlier and arrest the defects. This can help the project teams to deliver the product on time without defects. There by the cost of the projects can be reduced which in turn will have high customer satisfaction.  


Radiocarbon ◽  
2012 ◽  
Vol 54 (3-4) ◽  
pp. 979-991 ◽  
Author(s):  
R E Taylor ◽  
John Southon

We submit that anomalies in radiocarbon data in archaeological studies should be viewed positively as a stimulus to undertake further targeted research. Additional analyses to resolve anomalies have the potential to provide important insights into heretofore unstudied or incompletely understood depositional or geochemical processes affecting 14C values, particularly in certain types of samples and samples from certain types of environments. We consider 2 major categories or sources of 14C dating anomalies that we posit are mostly responsible for the vast majority of problematic 14C results: anomalous sample contexts and anomalous sample composition. Two additional sources of 14C anomalies are much more rarely encountered. Six case studies taken from New World archaeological studies are briefly presented to provide examples of where questions concerning the validity of 14C measurements generated additional and ultimately more accurate understandings of temporal relationships. AMS-based 14C measurement technology has rendered detailed investigations of 14C anomalies routinely feasible.


2019 ◽  
Vol 42 ◽  
Author(s):  
Paul Benjamin Badcock ◽  
Axel Constant ◽  
Maxwell James Désormeau Ramstead

Abstract Cognitive Gadgets offers a new, convincing perspective on the origins of our distinctive cognitive faculties, coupled with a clear, innovative research program. Although we broadly endorse Heyes’ ideas, we raise some concerns about her characterisation of evolutionary psychology and the relationship between biology and culture, before discussing the potential fruits of examining cognitive gadgets through the lens of active inference.


1994 ◽  
Vol 72 (03) ◽  
pp. 426-429 ◽  
Author(s):  
S Kitchen ◽  
I D Walker ◽  
T A L Woods ◽  
F E Preston

SummaryWhen the International Normalised Ratio (INR) is used for control of oral anticoagulant therapy the same result should be obtained irrespective of the laboratory reagent used. However, in the UK National External Quality Assessment Scheme (NEQAS) for Blood Coagulation INRs determined using different reagents have been significantly different.For 18 NEQAS samples Manchester Reagent (MR) was associated with significantly lower INRs than those obtained using Diagen Activated (DA, p = 0.0004) or Instrumentation Laboratory PT-Fib HS (IL, p = 0.0001). Mean INRs for this group were 3.15, 3.61, and 3.65 for MR, DA, and IL respectively. For 61 fresh samples from warfarin-ised patients with INRs of greater than 3.0 the relationship between thromboplastins in respect of INR was similar to that observed for NEQAS data. Thus INRs obtained with MR were significantly lower than with DA or IL (p <0.0001). Mean INRs for this group were 4.01, 4.40, and 4.59 for MR, DA, and IL respectively.We conclude that the differences between INRs measured with the thromboplastins studied here are sufficiently great to influence patient management through warfarin dosage schedules, particularly in the upper therapeutic range of INR. There is clearly a need to address the issues responsible for the observed discrepancies.


2016 ◽  
pp. 137-142
Author(s):  
V.O. Benyuk ◽  
◽  
V.M. Goncharenko ◽  
T.R. Nykoniuk ◽  
◽  
...  

The objective: to еxplore the relationship between the activity of endometrial proliferation and the state of the local immune response in the uterus in the conditions berprestasi process. Patients and methods. Examined 228 women of reproductive and perimenopausal age with endometrial pathology using ultrasound and then performing hysteroresectoscopy. Determination of the concentrations of the cytokines IL-1, IL-2, IL-6 and TNF was performed by solid phase ELISA. Results. Found a trend that confirms the loss of sensitivity to hormones at the stage of malignancy of the endometrium and can be used as diagnostic determinants in determining the nature of intrauterine pathology and criterion of the effectiveness of conservative therapy. Conclusion. Improving etiopatogenetice approach to the therapy of hyperplastic proce.sses of endometrium with determination of receptor phenotype of the endometrium is a research direction in modern gynecology, which will help to improve the results of treatment and prevention of intrauterine pathology. Key words: endometrial hyperplasia,the receptors for progesterone and estrogen, immunohistochemical method.


2012 ◽  
Vol 34 (3) ◽  
pp. 169-184 ◽  
Author(s):  
Hoang Thi Bich Ngoc

Vertical axis wind turbine technology has been applied last years, very long after horizontal axis wind turbine technology. Aerodynamic problems of vertical axis wind machines are discussible. An important problem is the determination of the incidence law in the interaction between wind and rotor blades. The focus of the work is to establish equations of the incidence depending on the blade azimuth, and to solve them. From these results, aerodynamic torques and power can be calculated. The incidence angle is a parameter of velocity triangle, and both the factors depend not only on the blade azimuth but also on the ratio of rotational speed and horizontal speed. The built computational program allows theoretically selecting the relationship of geometric parameters of wind turbine in accordance with requirements on power, wind speed and installation conditions.


1986 ◽  
Vol 14 (4) ◽  
pp. 201-218 ◽  
Author(s):  
A. G. Veith

Abstract This four-part series of papers addresses the problem of systematic determination of the influence of several tire factors on tire treadwear. Both the main effect of each factor and some of their interactive effects are included. The program was also structured to evaluate the influence of some external-to-tire conditions on the relationship of tire factors to treadwear. Part I describes the experimental design used to evaluate the effects on treadwear of generic tire type, aspect ratio, tread pattern (groove or void level), type of pattern (straight rib or block), and tread compound. Construction procedures and precautions used to obtain a valid and functional test method are included. Two guiding principles to be used in the data analyses of Parts II and III are discussed. These are the fractional groove and void concept, to characterize tread pattern geometry, and a demonstration of the equivalence of wear rate for identical compounds on whole tread or multi-section tread tires.


2017 ◽  
Vol 3 (1) ◽  
pp. 42
Author(s):  
Roshanira Che Mohd Noor ◽  
Nur Atiqah Rochin Demong

Providing a safe and healthy workplace is one of the most effective strategies in for holding down the cost of doing construction business. It was a part of the overall management system to facilitate themanagement of the occupational health and safety risk that are associated with the business of the organization. Factors affected the awareness level inclusive of safety and health conditions, dangerous working area, long wait care and services and lack of emergency communication werethe contributed factors to the awareness level for the operational level. Total of 122 incidents happened at Telekom Malaysia Berhad as compared to year 2015 only 86 cases. Thus, the main objective of this study was to determine the relationship between safety and health factors and the awareness level among operational workers.The determination of this research was to increase the awareness level among the operational level workerswho committing to safety and health environment.


2013 ◽  
pp. 11-17
Author(s):  
Thi Tuy Ha Nguyen ◽  
Thi Minh Thi Ha

Background: The role of p53 gene in the gastric cancer is still controversial. This study is aimed at determining the rate of the p53 gene codon 72 polymorphisms in gastric cancer patients and evaluating the relationship between these polymorphisms and endoscopic and histopathological features of gastric cancer. Patients and methods: Sixty eight patients with gastric cancer (cases) and one hundred and thirty six patients without gastric cancer (controls) were enrolled. p53 gene codon 72 polymorphisms were determined by PCR-RFLP technique with DNA extracted from samples of gastric tissue. Results: In the group of gastric cancer, Arginine/Argnine, Arginine/Proline and Proline/Proline genotypes were found in 29.4%, 42.7% and 27.9%, respectively. The differences of rates were not statistically significant between cases and controls (p > 0,05). In males, the Proline/Proline genotype was found in 38.1% in patients with gastric cancer and more frequent in patients without gastric cancer (15.7%, p = 0,01). An analysis of ROC curve showed that the cut-off was the age of 52 in the Proline/Proline genotype, but it was 65 years old in the Arginine/Proline genotype. The Proline/Proline genotype was found in 41.9% in Borrmann III/IV gastric cancer, this rate was higher than Borrmann I/II gastric cancer (16.2%, p = 0.037) and also higher than controls (18.4%, p = 0,01). The rate of Proline/Proline genotype was 41.7% in the diffuse gastric cancer, it was higher than in controls (p = 0,023). Conclusion: No significative difference of rate was found in genotypes between gastric cancer group and controls. However, there was the relationship between Proline/Proline genotype and gastric cancer in males, Borrmann types of gastric cancer, the diffuse gastric cancer. Key words: polymorphism, codon 72, p53 gene, PCR - RFLP, gastric cancer.


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