Frequency Distribution of Radiocarbon Dates as a Tool for Reconstructing Environmental Changes

Large sets of radiocarbon dates of 1019 peat, 155 speleothem, and 100 tufa samples, as well as dates of 330 fluvial samples, were investigated in order to estimate environmental variability during the last 16,000 calendar years in Poland. All 14C dating was carried out in the Gliwice Radiocarbon Laboratory, and results are stored in the RoS database. Probability density functions (PDFs) were created by summing up (on the calendar timescale) individual age probability distributions of all dates for different types of material and for different regions of Poland. We used an updated version of the Gliwice Radiocarbon Laboratory calibration program GdCALIB. The 14C dates were calibrated using the IntCal04 calibration curve (Reimer et al. 2004), and results were compared with other paleoenvironmental records. The authors conclude that analyzing PDFs of different types of sediments can be helpful in the qualitative reconstruction of the past environment. The PDF for peat samples primarily reflects paleohydrological conditions; the PDFs for speleothem and tufa samples reflect changes in temperature and humidity, while analysis of the PDF created for fluvial data is in a general agreement with the PDFs constructed for peat samples.

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Climate and environmental context of the Mongol invasion of Syria and defeat at ‘Ayn Jālūt (1258–1260 CE)

Erdkunde ◽

10.3112/erdkunde.2021.02.02 ◽

2021 ◽

Vol 75 (2) ◽

pp. 87-104

Author(s):

Nicola Di Cosmo ◽

Sebastian Wagner ◽

Ulf Büntgen

Keyword(s):

Strategic Alliances ◽

Turning Point ◽

Environmental Changes ◽

Environmental Variability ◽

State Of The Art ◽

Eastern Mediterranean ◽

The Caucasus ◽

Mountainous Regions ◽

The Past ◽

Climate Reconstructions

After a successful conquest of large parts of Syria in 1258 and 1259 CE, the Mongol army lost the battle of 'Ayn Jālūt against Mamluks on September 3, 1260 CE. Recognized as a turning point in world history, their sudden defeat triggered the reconfiguration of strategic alliances and geopolitical power not only in the Middle East, but also across much of Eurasia. Despite decades of research, scholars have not yet reached consensus over the causes of the Mongol reverse. Here, we revisit previous arguments in light of climate and environmental changes in the aftermath of one the largest volcanic forcings in the past 2500 years, the Samalas eruption ~1257 CE. Regional tree ring-based climate reconstructions and state-of-the-art Earth System Model simulations reveal cooler and wetter conditions from spring 1258 to autumn 1259 CE for the eastern Mediterranean/Arabian region. We therefore hypothesize that the post-Samalas climate anomaly and associated environmental variability affected an estimated 120,000 Mongol soldiers and up to half a million of their horses during the conquest. More specifically, we argue that colder and wetter climates in 1258 and 1259 CE, while complicating and slowing the campaign in certain areas, such as the mountainous regions in the Caucasus and Anatolia, also facilitated the assault on Syria between January and March 1260. A return to warmer and dryer conditions in the summer of 1260 CE, however, likely reduced the regional carrying capacity and may therefore have forced a mass withdrawal of the Mongols from the region that contributed to the Mamluks’ victory. In pointing to a distinct environmental dependency of the Mongols, we offer a new explanation of their defeat at 'Ayn Jālūt, which effectively halted the further expansion of the largest ever land-based empire.

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New 14C evidence for the Late Neolithic-Early Bronze Age transition in Southeast Europe

Open Journal of Archaeometry ◽

10.4081/arc.2014.5262 ◽

2014 ◽

Vol 2 (1) ◽

Cited By ~ 6

Author(s):

Yannis Maniatis ◽

Zoï Tsirtsoni ◽

Christine Oberlin ◽

Pascal Darcque ◽

Chaido Koukouli-Chryssanthaki ◽

...

Keyword(s):

Bronze Age ◽

Environmental Changes ◽

Early Bronze Age ◽

Human History ◽

Southeast Europe ◽

Late Neolithic ◽

Radiocarbon Dates ◽

Different Types ◽

The One ◽

Neighbouring Island

The transition from the Late Neolithic (LN) period (locally also called Final Neolithic or Chalcolithic) to the Early Bronze Age (EBA) in Greece and the Southeast Balkans is an obscure period in human history. Previous radiocarbon evidence showed that in settlements with stratigraphical sequences stretching out on both periods, the absolute dates featured a gap ranging from 700 to 1000 years (roughly between 4000 and 3300/3000 cal. BC). On the other hand, there is only scarce evidence about settlements that would have been founded during the missing period, thus arising questions of paramount importance about the human occupational strategies in this period. Investigation tackling this particular problem is carried out within the framework of a broader research project (Balkans-4000) funded by the French National Research Agency (ANR). Here we discuss the latest radiocarbon results from three recently excavated multilayer settlements on the continental Greek Eastern Macedonia: Dikili Tash, Kryoneri and Sidirokastro. In all cases, the existing LN radiocarbon dates do not go beyond about 4000 BC, whereas the earliest EBA layer dates begin at around 3300 BC. A date in the last 1/3rd of the 4th millennium BC is also the date suggested for the one-layer transitional settlement on the neighbouring island of Thasos (Aghios Ioannis). The fact that the gap affects settlements of different types and locations, although there are no signs of major environmental changes, suggests that the reasons of their possible total or partial abandonment are more likely to be social than strictly environmental.

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Radiocarbon Calibration and Analysis of Stratigraphy: The OxCal Program

Radiocarbon ◽

10.1017/s0033822200030903 ◽

1995 ◽

Vol 37 (2) ◽

pp. 425-430 ◽

Cited By ~ 1399

Author(s):

Christopher Bronk Ramsey

Keyword(s):

Probability Distributions ◽

Individual Case ◽

Archaeological Sites ◽

Radiocarbon Dates ◽

Site Analysis ◽

Extra Information ◽

Dating Methods ◽

Different Types ◽

Types Of Information ◽

Radiocarbon Calibration

People usually study the chronologies of archaeological sites and geological sequences using many different kinds of evidence, taking into account calibrated radiocarbon dates, other dating methods and stratigraphic information. Many individual case studies demonstrate the value of using statistical methods to combine these different types of information. I have developed a computer program, OxCal, running under Windows 3.1 (for IBM PCs), that will perform both 14C calibration and calculate what extra information can be gained from stratigraphic evidence. The program can perform automatic wiggle matches and calculate probability distributions for samples in sequences and phases. The program is written in C++ and uses Bayesian statistics and Gibbs sampling for the calculations. The program is very easy to use, both for simple calibration and complex site analysis, and will produce graphical output from virtually any printer.

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Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053310 ◽

1982 ◽

Vol 40 ◽

pp. 118-119

Author(s):

U. Aebi ◽

P. Rew ◽

T.-T. Sun

Keyword(s):

Electron Microscopy ◽

Structural Organization ◽

Cell Types ◽

Structural Features ◽

Molecular Architecture ◽

The Past ◽

Keratin Filaments ◽

Different Types ◽

10 Nm Filaments ◽

Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

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Enzyme Immobilization on Nanomaterials for Biosensor and Biocatalyst in Food and Biomedical Industry

Current Pharmaceutical Design ◽

10.2174/1381612825666190712181403 ◽

2019 ◽

Vol 25 (24) ◽

pp. 2661-2676 ◽

Cited By ~ 1

Author(s):

Sundaresan Bhavaniramya ◽

Ramar Vanajothi ◽

Selvaraju Vishnupriya ◽

Kumpati Premkumar ◽

Mohammad S. Al-Aboody ◽

...

Keyword(s):

Enzyme Activity ◽

Enzyme Immobilization ◽

Food Industry ◽

Environmental Changes ◽

Immobilized Enzymes ◽

Food Industries ◽

Physiological Processes ◽

Different Types ◽

Simple Processing ◽

Biomedical Industry

Enzymes exhibit a great catalytic activity for several physiological processes. Utilization of immobilized enzymes has a great potential in several food industries due to their excellent functional properties, simple processing and cost effectiveness during the past decades. Though they have several applications, they still exhibit some challenges. To overcome the challenges, nanoparticles with their unique physicochemical properties act as very attractive carriers for enzyme immobilization. The enzyme immobilization method is not only widely used in the food industry but is also a component methodology in the pharmaceutical industry. Compared to the free enzymes, immobilized forms are more robust and resistant to environmental changes. In this method, the mobility of enzymes is artificially restricted to changing their structure and properties. Due to their sensitive nature, the classical immobilization methods are still limited as a result of the reduction of enzyme activity. In order to improve the enzyme activity and their properties, nanomaterials are used as a carrier for enzyme immobilization. Recently, much attention has been directed towards the research on the potentiality of the immobilized enzymes in the food industry. Hence, the present review emphasizes the different types of immobilization methods that is presently used in the food industry and other applications. Various types of nanomaterials such as nanofibers, nanoflowers and magnetic nanoparticles are significantly used as a support material in the immobilization methods. However, several numbers of immobilized enzymes are used in the food industries to improve the processing methods which not only reduce the production cost but also the effluents from the industry.

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Is Healthcare Special?

10.1093/oso/9780190886134.003.0002 ◽

2018 ◽

Author(s):

Gordon Moore ◽

John A. Quelch ◽

Emily Boudreau

Keyword(s):

Consumer Choice ◽

Special Relationship ◽

Individual Choice ◽

Health Consequences ◽

Critical Question ◽

The Past ◽

Different Types ◽

Collective Benefit ◽

Patient Ethics

Chapter 2 asks the critical question of whether healthcare is different from other consumer-driven markets. In the past, many pushed back on the notion that healthcare could be a consumer-driven industry, arguing that it is fundamentally different from other markets. This chapter acknowledges and reviews these critiques, highlighting four areas that might present challenges to increasing consumer choice in healthcare: the special relationship between doctor and patient, ethics and morality, individual choice versus collective benefit, and the health consequences of consumer choice. In doing so, this chapter also presents a schematic for thinking about the different types of healthcare choices, arguing that not all choices are equal and consumers may be more prepared to make decisions in some areas as opposed to others. In presenting the counterargument to consumer choice, this chapter asks the reader to consider the drawbacks and potential limitations of consumer choice in healthcare.

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Vietnamese Historical Writing

10.1093/oso/9780199225996.003.0028 ◽

2018 ◽

Author(s):

Patricia Pelley

Keyword(s):

Cold War ◽

East Asian ◽

History Writing ◽

Southern State ◽

The Past ◽

South Vietnam ◽

Political Function ◽

Different Types ◽

The Cold War ◽

North Vietnam

This chapter demonstrates how the process of decolonization and the ensuing separation of Vietnam into a northern and southern state as part of the Cold War in Asia led to different types of history-writing. In both Vietnamese regimes, the writing of history had to serve the state, and in both countries historians emphasized its political function. Whereas North Vietnam located itself in an East Asian and Marxist context, historians of South Vietnam positioned it within a Southeast Asian setting and took a determinedly anti-communist position. After 1986—over a decade after reunification—with past tensions now relaxed, the past could be revaluated more openly under a reformist Vietnamese government that now also permitted much greater interaction with foreign historians.

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Calibration of Radiocarbon Dates for the Late Pleistocene Using U/Th Dates on Stalagmites

Radiocarbon ◽

10.1017/s003382220004087x ◽

1997 ◽

Vol 39 (1) ◽

pp. 27-32 ◽

Cited By ~ 40

Author(s):

John C. Vogel ◽

Joel Kronfeld

Keyword(s):

South Africa ◽

Magnetic Dipole ◽

Satisfactory Agreement ◽

Late Pleistocene ◽

Calibration Curve ◽

Dipole Field ◽

Radiocarbon Dates ◽

The Past ◽

The Earth ◽

Magnetic Dipole Field

Twenty paired 14C and U/Th dates covering most of the past 50,000 yr have been obtained on a stalagmite from the Cango Caves in South Africa as well as some additional age-pairs on two stalagmites from Tasmania that partially fill a gap between 7 ka and 17 ka ago. After allowance is made for the initial apparent 14C ages, the age-pairs between 7 ka and 20 ka show satisfactory agreement with the coral data of Bard et al. (1990, 1993). The results for the Cango stalagmite between 25 ka and 50 ka show the 14C dates to be substantially younger than the U/Th dates except at 49 ka and 29 ka, where near correspondence occurs. The discrepancies may be explained by variations in 14C production caused by changes in the magnetic dipole field of the Earth. A tentative calibration curve for this period is offered.

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Different Types of Auricular Keloids and Treatment by Intralesional Cryosurgery: Best Practice for Obtaining Long-Lasting Clinical Results

Dermatology ◽

10.1159/000514954 ◽

2021 ◽

pp. 1-10

Author(s):

Yaron Har-Shai ◽

Lior Har-Shai ◽

Viktor A. Zouboulis ◽

Christos C. Zouboulis

Keyword(s):

Quality Of Life ◽

Body Image ◽

Recurrence Rate ◽

Best Practice ◽

Clinical Results ◽

Psychosocial Impact ◽

Aesthetic Outcome ◽

The Past ◽

Different Types

Background: Auricular keloids belong to the most perplexing medical conditions, which have significant psychosocial impact on the patient’s body image and quality of life. Summary: The article is purposed to provide dermatologists and plastic surgeons with the best proven practice using intralesional cryosurgery for the treatment of the different auricular keloid types in order to obtain superior clinical results by minimizing the probability of recurrence. In the past 20 years, the authors have developed novel procedures in order to increase the effectiveness of intralesional cryosurgery on auricular keloids, including hydrodissection, warm gauze technique, and excision of dangling skin. Long-lasting clinical results with a low recurrence rate and a satisfactory aesthetic outcome are achieved with no deformation of the ear framework.

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Paleoenvironmental analysis of wet meadow in the Deseado Massif: Implications for the Holocene occupation of Argentinian Patagonia

The Holocene ◽

10.1177/09596836211025969 ◽

2021 ◽

pp. 095968362110259

Author(s):

Bruno Mosquera ◽

María V Mancini

Keyword(s):

Environmental Changes ◽

Low Energy ◽

Semiarid Region ◽

Human Occupation ◽

Wet Meadow ◽

Radiocarbon Dates ◽

Sedimentation Environment ◽

Dry Conditions ◽

Paleoenvironmental Analysis ◽

Deseado Massif

Paleoenvironmental data from wet-meadow environments in the arid-semiarid region of Patagonia are still incipient and the paleoenvironmental records came from pollen sequences of caves and rockshelters. The main reasons to study wetland records are their undisturbed (by humans) sedimentologic continuity, in contrast to deposits in rock shelters and caves; and their regional presentation of environmental changes that can be compared to archeological data. The aim of this paper is to evaluate the past hydrological dynamic of a wet-meadow from Deseado Massif and its relationship with the human occupation. For this purpose, we present the results of the sediment and pollen analysis of Mallín La Primavera wet-meadow that provide a sequence starting in the mid-Holocene. The results indicate a lower water table in the mallín prior to 6900 cal yr BP. Sediment analysis indicates low energy sedimentation environment with flood events and very low energy streams. Human occupational data show chronological discontinuities in mid-Holocene in several regions of Patagonia and the southern cone. In the studied region, two chronological hiatuses (7828–6434 cal yr BP and 3005–2710 cal yr BP) where recognized that appear to correlate with shrub steppes, indicating dry conditions. These conditions may explain the lack of archeological radiocarbon dates in the area during this period. The integration of sediment and pollen results from the Deseado Massif indicates dry and windy conditions for the middle Holocene. The lack of archeological radiocarbon dates would have been influenced by the loss of moisture in water sources such as springs and their associated wet meadows ( mallines).

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