MAYA COASTAL PRODUCTION, EXCHANGE, LIFE STYLE, AND POPULATION MOBILITY: A VIEW FROM THE PORT OF XCAMBO, YUCATAN, MEXICO

2014 ◽  
Vol 25 (1) ◽  
pp. 221-238 ◽  
Author(s):  
Thelma Sierra Sosa ◽  
Andrea Cucina ◽  
T. Douglas Price ◽  
James H. Burton ◽  
Vera Tiesler

AbstractAnchored in archaeological, bioarchaeological, and chemical research conducted at the coastal enclave of Xcambo, this paper examines Classic period Maya coastal saline economic production and exchange, along with the lifestyle, ethnicity, and mobility of the traders. Nestled in the coastal marshlands of the northern Yucatan, Mexico, Xcambo functioned as a salt production center and port during its occupation, maintaining long-reaching ties with other parts of the Maya world and Veracruz. Considered together, the different data sets document a reorientation in Xcambo's exchange routes and connections, which are echoed by increasingly diverse cultural affiliations and an increasing geographic mobility of Xcambo's merchants. This new information confirms the known pattern of gradually intensifying, though still relatively independent, trade dynamics along the Maya coast in the centuries leading up to the so-called “Maya collapse” and the rise of a new merchant league under the control of Chichen Itza. It was this new order that probably led to the swift end of Xcambo soon aftera.d.700.

Author(s):  
Ned Augenblick ◽  
Matthew Rabin

Abstract When a Bayesian learns new information and changes her beliefs, she must on average become concomitantly more certain about the state of the world. Consequently, it is rare for a Bayesian to frequently shift beliefs substantially while remaining relatively uncertain, or, conversely, become very confident with relatively little belief movement. We formalize this intuition by developing specific measures of movement and uncertainty reduction given a Bayesian’s changing beliefs over time, showing that these measures are equal in expectation and creating consequent statistical tests for Bayesianess. We then show connections between these two core concepts and four common psychological biases, suggesting that the test might be particularly good at detecting these biases. We provide support for this conclusion by simulating the performance of our test and other martingale tests. Finally, we apply our test to data sets of individual, algorithmic, and market beliefs.


Author(s):  
D. Browne

AREAS in which white clover grows reasonably well have the potential of carrying a certain stocking rate without using fertilizer nitrogen. The development of dairying in such areas will logically use the best available legumes to increase stock carrying capacity to its economic optimum. Evaluating the place of fertilizer nitrogen in these areas will therefore be concerned with the establishment of the maximum economic production from legume-based pastures, and secondly with the increase in production per unit area possible using a range of nitrogen levels. Where the research objective is to provide guidance to a developing. industry, the optimum production from both nitrogen' sources must be defined using available information on the best management systems, most suitable .legumes, most effective rhizobium, etc. This approach accepts that new information on any of the factors involved could increase the stocking rate which gives optimum production from either nitrogen source and would advocate that some of the research resources should be used to examine such management factors. If this guidance is not available, decisions will still have to be made by the industry but at greater risk (Morley and Spedding, 1968).


Author(s):  
Andrzej Katrusiak

The diamond-anvil cell (DAC) was invented 60 years ago, ushering in a new era for material sciences, extending research into the dimension of pressure. Most structural determinations and chemical research have been conducted at ambient pressure, i.e. the atmospheric pressure on Earth. However, modern experimental techniques are capable of generating pressure and temperature higher than those at the centre of Earth. Such extreme conditions can be used for obtaining unprecedented chemical compounds, but, most importantly, all fundamental phenomena can be viewed and understood from a broader perspective. This knowledge, in turn, is necessary for designing new generations of materials and applications, for example in the pharmaceutical industry or for obtaining super-hard materials. The high-pressure chambers in the DAC are already used for a considerable variety of experiments, such as chemical reactions, crystallizations, measurements of electric, dielectric and magnetic properties, transformations of biological materials as well as experiments on living tissue. Undoubtedly, more applications involving elevated pressure will follow. High-pressure methods become increasingly attractive, because they can reduce the sample volume and compress the intermolecular contacts to values unattainable by other methods, many times stronger than at low temperature. The compressed materials reveal new information about intermolecular interactions and new phases of single- and multi-component compounds can be obtained. At the same time, high-pressure techniques, and particularly those of X-ray diffraction using the DAC, have been considerably improved and many innovative developments implemented. Increasingly more equipment of in-house laboratories, as well as the instrumentation of beamlines at synchrotrons and thermal neutron sources are dedicated to high-pressure research.


2011 ◽  
Vol 77 (19) ◽  
pp. 7000-7006 ◽  
Author(s):  
Nicola M. Reid ◽  
Sarah L. Addison ◽  
Lucy J. Macdonald ◽  
Gareth Lloyd-Jones

ABSTRACTHuhu grubs (Prionoplus reticularis) are wood-feeding beetle larvae endemic to New Zealand and belonging to the family Cerambycidae. Compared to the wood-feeding lower termites, very little is known about the diversity and activity of microorganisms associated with xylophagous cerambycid larvae. To address this, we used pyrosequencing to evaluate the diversity of metabolically active and inactive bacteria in the huhu larval gut. Our estimate, that the gut harbors at least 1,800 phylotypes, is based on 33,420 sequences amplified from genomic DNA and reverse-transcribed RNA. Analysis of genomic DNA- and RNA-derived data sets revealed that 71% of all phylotypes (representing 95% of all sequences) were metabolically active. Rare phylotypes contributed considerably to the richness of the community and were also largely metabolically active, indicating their participation in digestive processes in the gut. The dominant families in the active community (RNA data set) includedAcidobacteriaceae(24.3%),Xanthomonadaceae(16.7%),Acetobacteraceae(15.8%),Burkholderiaceae(8.7%), andEnterobacteriaceae(4.1%). The most abundant phylotype comprised 14% of the active community and affiliated withDyella ginsengisoli(Gammaproteobacteria), suggesting that aDyella-related organism is a likely symbiont. This study provides new information on the diversity and activity of gut-associated microorganisms that are essential for the digestion of the nutritionally poor diet consumed by wood-feeding larvae. Many huhu gut phylotypes affiliated with insect symbionts or with bacteria present in acidic environments or associated with fungi.


1991 ◽  
Vol 113 (1) ◽  
pp. 74-87 ◽  
Author(s):  
J. H. Lever ◽  
D. W. Bass ◽  
C. F. M. Lewis ◽  
K. Klein ◽  
D. Diemand ◽  
...  

The Dynamics of Iceberg Grounding and Scouring (DIGS) experiment was conducted in the Labrador Sea during August 1985. The objectives of the experiment were to obtain full-scale data sets documenting iceberg/seabed interactions, and to obtain by direct observation new information regarding the processes of iceberg scour formation and degradation. Utilizing a vessel and a helicopter, measurements were made of icebergs’ above and below-water shapes, plus local winds, waves, currents and tides. Special self-contained motion monitoring packages were deployed by helicopter on icebergs thought to be good grounding candidates. Seabed observations were made directly using the submersible Pisces IV, and extensive side-scan sonar data were collected. This paper describes two dynamic iceberg/seabed interaction events documented during DIGS: the roll/pitting behavior of the 1.2-million-ton domed iceberg “Bertha,” and the split/grounding behavior of the 7.7-million-ton tabular iceberg “Gladys.” This latter event is particularly interesting due to its very energetic nature, and the fact that it represents the only full-scale observation of any iceberg impact with sufficient documentation to yield estimates of the interaction forces. Subsequent to the experiment, the recorded above and below-water shapes were used to obtain hydrostatic stability maps for these icebergs. A time stepping procedure was also developed to re-create these two dynamic events, and comparisons between the observed and simulated motions are provided in this paper.


1997 ◽  
Vol 62 (2) ◽  
pp. 300-318 ◽  
Author(s):  
Jeanne E. Arnold ◽  
Roger H. Colten ◽  
Scott Pletka

Archaeological and ethnohistorical researchers in California are reaping the rewards from a wealth of new information about precontact and early historical cultural diversity, technologies, and marine and terrestrial ecosystems. Our recent investigations into the later prehistory of the island groups of southern California have centered on processes of sociopolitical evolution, including the emergence of status differentiation, evidence for intensification of craft production, and associated changes in human uses of animal resources as societies became more complex. We have linked some specific changes in diet, labor organization, and exchange to documented climatic disturbances, suggesting that opportunities created by such disruptions may have accounted in part for the timing of changes, but were not their cause in any mechanistic or simplistic sense. A recent American Antiquity report overlooks the primary results of this research and isolates the environmental data from a broad multidimensional model of cultural change in coastal California. We provide an update on the status of Channel Islands archaeology and identify the fundamental problems with approaches that extract and decontextualize environmental processes from cultural processes by assessing limited faunal data sets.


1998 ◽  
Vol 5 (3) ◽  
pp. 222-225 ◽  
Author(s):  
Masaki Yamamoto ◽  
Takashi Kumasaka ◽  
Tetsuro Fujisawa ◽  
Tatzuo Ueki

SPring-8 RIKEN beamline I has been designed and developed for structural biology research by the Institute of Physical and Chemical Research (RIKEN). The beamline consists of two experimental stations for protein crystallography and small-angle X-ray scattering. Both types of experiments can be carried out simultaneously, with dichromatic synchrotron radiation emitted from two coaxial undulators with vertical polarization. The branched beams are generated by a transparent diamond crystal. With synchrotron radiation, the multiple-wavelength anomalous-dispersion (MAD) method, which gives phases from a single anomalous scatterer, has been developed. Anomalous scattering contributes a small proportion of the diffraction intensity so that the accuracy of intensity data is important. The protein crystallography branch of RIKEN beamline I has been designed based on a `trichromatic concept' to optimize MAD data collection. This concept requires the quasi-simultaneous collection, by use of a `trichromator', of three intensity data sets at three different wavelengths from a single protein crystal without changing any settings. The main feature of the concept is the minimization of systematic errors in the measurement of anomalous diffraction for the MAD method. Initial commissioning of the beamline has provided three different monochromated undulator beams, which were successfully observed on the phosphor screen located at the near end of the trichromator.


2018 ◽  
Author(s):  
Yu Li ◽  
Zhongxiao Li ◽  
Lizhong Ding ◽  
Yuhui Hu ◽  
Wei Chen ◽  
...  

ABSTRACTMotivationIn most biological data sets, the amount of data is regularly growing and the number of classes is continuously increasing. To deal with the new data from the new classes, one approach is to train a classification model, e.g., a deep learning model, from scratch based on both old and new data. This approach is highly computationally costly and the extracted features are likely very different from the ones extracted by the model trained on the old data alone, which leads to poor model robustness. Another approach is to fine tune the trained model from the old data on the new data. However, this approach often does not have the ability to learn new knowledge without forgetting the previously learned knowledge, which is known as the catastrophic forgetting problem. To our knowledge, this problem has not been studied in the field of bioinformatics despite its existence in many bioinformatic problems.ResultsHere we propose a novel method, SupportNet, to solve the catastrophic forgetting problem efficiently and effectively. SupportNet combines the strength of deep learning and support vector machine (SVM), where SVM is used to identify the support data from the old data, which are fed to the deep learning model together with the new data for further training so that the model can review the essential information of the old data when learning the new information. Two powerful consolidation regularizers are applied to ensure the robustness of the learned model. Comprehensive experiments on various tasks, including enzyme function prediction, subcellular structure classification and breast tumor classification, show that SupportNet drastically outperforms the state-of-the-art incremental learning methods and reaches similar performance as the deep learning model trained from scratch on both old and new data.AvailabilityOur program is accessible at: https://github.com/lykaust15/SupportNet.


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