Method-dependent variations in stable isotope results for structural carbonate in bone bioapatite

Stable carbon and oxygen isotope values (δ¹³C, δ¹⁸O) were obtained for structural carbonate in the bioapatite of archaeological bones from Guatemala and Sudan using several common analytical methods. For the Sudan samples, the different methods produced δ¹³C values within ±0.1‰ and δ¹⁸O values within ±0.7‰, on average. The isotopic results for the Guatemala samples were similar in reproducibility to the Sudan samples when obtained using methods that employed lower reaction temperatures and reactions in sealed vessels. However, many Guatemala samples had highly variable and extremely low δ¹⁸O values when reacted at higher temperatures in vessels that remained open to cryogenic traps. The latter arrangement caused reaction products to be removed immediately upon their production. The anomalously low δ¹⁸O values are related to the production of a contaminant gas that causes the m/z 46/44 ratio to be lowered, either by adding to the m/z 44 peak or subtracting from the m/z 46 peak. That said, potential contaminant materials were not detectable in “anomalous” bones using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction, or inductively-coupled plasma atomic emission spectroscopy. However, subtle structural and chemical differences between “normal” and “anomalous” samples were observed, most notably in the FTIR ν₂ CO₃ domain. We suggest that these changes promote volatilization of an oxyphosphorus compound and oxygen isotope fractionation between PO⁻ derived from this compound and CO₂ derived from bone carbonate. Production of the contaminant gas and the related “anomalous” δ¹⁸O values is reversible if the reaction occurs within a sealed vessel for a sufficient period of time, which allows a “back-reaction” to occur.     

Book reviews

THE UNITED STATES IN WORLD AFFAIRS 1949. By Richard P. Stebbins and the Research Staff of the Council of Foreign Relations. New York, Harper and Brothers, 1950.

CONDITIONS OF ECONOMIC PROGRESS. By Colin Clark. 2nd Edition. London, Macmillan, 1951. xvi ‐J‐ 584 pp. 50/‐ stg.

INDIAN‐AMERICAN RELATIONS. Proceedings of the India‐America Conference held in New Delhi in December 1949. Issued under the joint auspices of the Indian Council of World Affairs and the American Institute of Pacific Relations. Oxford University Press. v + 79 pp.

THE STATE OF ASIA: A Contemporary Survey. By Lawrence K. Rosinger and Associates. Issued under the auspices of the American Institute of Pacific Relations. Alfred A. Knopf, 1951. 512 pp. Bibliography and index.

UNITED KINGDOM ADMINISTRATION AND INTERNATIONAL ORGANISATIONS: A Report by a Study Group of the Institute of Public Administration. R.I.I.A., 1951. 55 pp. 4/‐.     

Bernard Lamy,Empiricism, and Cartesianism

Bernard Lamy (1640–1715) is frequently included among the Cartesian Empiricists of the second half of the seventeenth century. He has also been described as an Augustinian who dabbled in Cartesianism. While acknowledging that there are both empiricist and Augustinian elements in his thought, I argue that it ought not be forgotten that there are central components of his philosophy that are both anti-empiricist and in opposition to Augustine. My aim in this paper, though, is not (merely) critical; I hope to show that Lamy provides us with one more example of the diversity present among the various thinkers labelled as ‘Cartesian’.     

The archaeology of World War II karst defences in the Pacific

During World War II, the Japanese military, using either their own or civilian labour, excavated tunnels into the limestone of many Pacific islands and modified natural caves for use as command posts, hospitals, combat positions, storage, and shelter. Civilians also used caves to shelter themselves during the war. This article introduces the archaeology of WWII caves and tunnels referred to collectively as ‘karst defences.’ While karst defences exist across the Pacific, little is known about these sites both historically and archaeologically. Based on a study in Saipan, Commonwealth of the Northern Mariana Islands, and analysis of karst defence construction and function, this article demonstrates that karst defence use extends beyond what has been described in historical accounts. The authors find that the sites in Saipan were used by three different groups of people and identifies distinct Japanese military and civilian sites and evidence of post-war use by the United States.     

Exploring Oyster (Crassostrea virginica) Habitat Collection via Oxygen Isotope Geochemistry and its Implications for Ritual and Mound Construction at Crystal River and Roberts Island,Florida

Research at Crystal River and Roberts Island Shell Mound Complex, on the western coast of Florida, USA, offers a quantitative assessment of the temporality of shell deposit construction, Native subsistence practices, and mobility patterns through stable oxygen isotope data from eastern oyster (C. virginica). The δ¹⁸O_water values of oysters vary synchronously with salinity, assuming relatively constant δ¹⁸O_water/salinity gradients since the time of occupation, allowing for an examination of shifts in oyster habitat exploitation over time. Our previous (Thompson et al. 2015) study indicated that midden accumulation occurred throughout the year, while oysters from mound deposits were collected in colder months. New data indicate that in addition to differential season of collection, habitat exploitation also varied. During early occupation at the site, oysters were collected primarily from lower saline habitats, while in later phases oysters were obtained from higher salinity waters; we relate this to a lower sea level and concomitant settlement shift seaward. Additionally, oyster from later mound contexts was collected from higher saline habitats relative to those in midden contexts; Native people may have targeted specific bioherms at certain times for the year for feasting-related mound construction.     

Winda Lingo Parugoneit1 or Why Set the Bush [On] Fire? Fire and Victorian Aboriginal People on the Colonial Frontier

There is an ethnographic and historical record that, despite its paucity, can offer specific insight into various contextual matters (purpose, motivations, acknowledgement) relating to how and why fire was being used by Victorian Aboriginal people in the nineteenth century. This insight is essential to developing cross-culturally appropriate land and fire management strategies in the present and into the future. This article demonstrates the need for further research into historical accounts of Aboriginal burning in Victoria.     

Modified Kaplan–Meier Estimator and Nelson–Aalen Estimator with Geographical Weighting for Survival Data

The Kaplan–Meier and Nelson–Aalen estimators are universally used methods in clinical studies. In a public health study, people often collect data from different locations of the medical services provider. When some studies need to consider survival curves from different locations, traditional estimators simply estimate the marginal survival curves using stratification. In this article, we use the idea from geographically weighted regression to add geographical weights to the observations to get modified versions of the Kaplan–Meier and Nelson–Aalen estimators which can represent the local survival curve and cumulative hazard. We use counting process methods to derive these modified estimators and to estimate their variances. In addition, we discuss some general spatial weighting functions which can be used in computing these estimators. Furthermore, we present simulation results to illustrate the performance of the modified estimators. Finally, we apply our method to prostate cancer data from the SEER cancer registry for the state of Louisiana.     

Comments on Robert Howse,Leo Strauss: Man of Peace

Robert Howse's book does a good and welcome job of showing a Leo Strauss who is far from the bloodstained “neoconservative” caricature that is so commonly presented. He rightly emphasizes Strauss's concern for decency and the keeping of peace where possible. Especially telling is his account of Strauss's view of Thucydides's alleged “realism.” He does a good job of showing how Strauss, like Thucydides, balances the claims of necessity with the substantive and practically important claims of justice. However, Howse pushes Strauss a little too far when it comes to his faith in permanently peaceful large federations and goes to excess in distancing himself from Strauss's neoconservative followers, at one point even falling into mischaracterization in doing so. If the purpose of this distancing was to make Strauss more acceptable to leftist critics, it is doubtful that this will succeed; if the purpose was less strategic and more personal, it seems an excessive response.     

Recent work on the Middle Palaeolithic of the Eastern Sahara

Recent research at the remote depression of Bir Tarfawi, in the hyperarid Eastern Sahara, has revealed a sequence of four, or possibly five, Pleistocene lake-episodes. The first lake was probably associated with a Late Acheulean and the remaining four with a Middle Palaeolithic, specifically with a Denticulate Aterian, industry. Lithostratigraphic, macrofaunal and microfaunal analyses have permitted a quite detailed reconstruction of the local environment during the periods of the last two lakes; during the period of the fourth lake, local rainfall may have beenca 600 mm per annum but was rather less during the time of the fifth lake. Investigation of some of the many associated archaeological sites is revealing a complex pattern of specialized site-types, including living-sites, primary and secondary workshops and primary and secondary butchery-sites. Specific types of sites are closely related to the local landscape. Preliminary analyses from several experimental methods of chronometric dating suggest that almost all of the sequence falls within the Middle Pleistocene.

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Résumé Des recherches récentes dans la dépression isolée de Bir Tarfawi dans le Sahara oriental hyperaride, ont révélé une séquence de quatre, ou peut être cinq, épisodes lacustres au Pléistocène. Le premier lac est probablement associé à un Acheuléen final, et les quatre autres au Paléolithique moyen, et spécifiquement à une industrie atérienne denticulée. Des analyses de lithostratigraphie, de macrofaune et de microfaune ont permis de reconstruire d'une façon assez détaillée l'environnement local pendant les périodes des deux derniers lacs. Pendant la période du quatrième lac, la pluviosité locale était peut être deca 600 mm par an, mais elle était un peu moindre à lépoque du cinquième lac. Les recherches dans certains des nombreux gisements archéologiques associés nous révèlent un schéma complexe de sites spécialisés, y compris des sites d'habitat, des ateliers primaires et secondaires, et des lieux de dépeçage primaires et secondaires. Certains types de gisement sont étroitement liés au paysage local. Des analyses préliminaires par plusieurs méthodes expérimentales de datation chronométrique suggèrent que presque toute la séquence appartient au Pléistocène moyen.