scholarly journals Combined dental wear and cementum analyses in ungulates reveal the seasonality of Neanderthal occupations in Covalejos Cave (Northern Iberia)

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Carlos Sánchez-Hernández ◽  
Lionel Gourichon ◽  
Eric Pubert ◽  
William Rendu ◽  
Ramón Montes ◽  
...  
Keyword(s):  
Accurate Determination ◽  
Dental Wear ◽  
Dental Cementum ◽  
Faunal Assemblages ◽  
Cantabrian Region ◽  
Different Seasons ◽  
Occupational Patterns ◽  
Cementum Analysis ◽  
First Time

Abstract We propose for the first time the use of the combination of two high-resolution techniques, dental wear (meso- and microwear) and dental cementum analyses, to gain a better understanding of Neanderthal subsistence strategies and occupational patterns. Dental wear analysis provides information not only on ungulate palaeodiet and palaeoenvironments but also on hunting time and seasons. Dental cementum analysis allows the accurate determination of the age and season at death of a prey. Our study has focused on the Cantabrian region and has applied both methods to investigate the Mousterian faunal assemblages in Covalejos Cave. Identification of the ungulate palaeodiet reveals information on the environmental conditions of the studied region. Moreover, it may facilitate observation on the evolution of both palaeodiet and palaeoenvironment throughout the site sequence. Results show a general stability in the palaeoenvironmental conditions and in the ungulate palaeodiet throughout the Mousterian sequence; this finding may be attributed to the role of the area as a climate refuge, and slight differences in levels 8, 7 and 4 suggest long- or short-term but repeated Neanderthal occupations at different seasons in the annual cycle.

scholarly journals Sulfur dioxide layer height retrieval from Sentinel-5 Precursor/TROPOMI using FP_ILM

2019 ◽  
Vol 12 (10) ◽  
pp. 5503-5517 ◽  
Author(s):  
Pascal Hedelt ◽  
Dmitry S. Efremenko ◽  
Diego G. Loyola ◽  
Robert Spurr ◽  
Lieven Clarisse
Keyword(s):  
Sulfur Dioxide ◽  
Accurate Determination ◽  
Volcanic Eruptions ◽  
Critical Parameters ◽  
Layer Height ◽  
Learning Machine ◽  
The Impact ◽  
First Time ◽  
Better Than

Abstract. The accurate determination of the location, height, and loading of sulfur dioxide (SO2) plumes emitted by volcanic eruptions is essential for aviation safety. The SO2 layer height is also one of the most critical parameters with respect to determining the impact on the climate. Retrievals of SO2 plume height have been carried out using satellite UV backscatter measurements, but, until now, such algorithms are very time-consuming. We have developed an extremely fast yet accurate SO2 layer height retrieval using the Full-Physics Inverse Learning Machine (FP_ILM) algorithm. This is the first time the algorithm has been applied to measurements from the TROPOMI instrument onboard the Sentinel-5 Precursor platform. In this paper, we demonstrate the ability of the FP_ILM algorithm to retrieve SO2 plume layer heights in near-real-time applications with an accuracy of better than 2 km for SO2 total columns larger than 20 DU. We present SO2 layer height results for the volcanic eruptions of Sinabung in February 2018, Sierra Negra in June 2018, and Raikoke in June 2019, observed by TROPOMI.

Endocranial Casts of Pre-Mammalian Therapsids Reveal an Unexpected Neurological Diversity at the Deep Evolutionary Root of Mammals

2017 ◽  
Vol 90 (4) ◽  
pp. 311-333 ◽  
Author(s):  
Julien Benoit ◽  
Vincent Fernandez ◽  
Paul R. Manger ◽  
Bruce S. Rubidge
Keyword(s):  
Brain Size ◽  
Accurate Determination ◽  
Mammalian Brain ◽  
Reliable Determination ◽  
Origin And Evolution ◽  
Show Evidence ◽  
Size And Morphology ◽  
First Time ◽  
Linear Manner

The origin and evolution of the mammalian brain has long been the focus of scientific enquiry. Conversely, little research has focused on the palaeoneurology of the stem group of Mammaliaformes, the Permian and Triassic non-mammaliaform Therapsida (NMT). This is because the majority of the NMT have a non-ossified braincase, making the study of their endocranial cast (sometimes called the “fossil brain”) problematic. Thus, descriptions of the morphology and size of NMT endocranial casts have been based largely on approximations rather than reliable determination. Accordingly, here we use micro-CT scans of the skulls of 1 Dinocephalia and 3 Biarmosuchia, which are NMT with a fully ossified braincase and thus a complete endocast. For the first time, our work enables the accurate determination of endocranial shape and size in NMT. This study suggests that NMT brain size falls in the upper range of the reptilian and amphibian variation. Brain size in the dicynodont Kawingasaurus is equivalent to that of early Mammaliaformes, whereas the Dinocephalia show evidence of a secondary reduction of brain size. In addition, unlike other NMT in which the endocast has a tubular shape and its parts are arranged in a linear manner, the biarmosuchian endocast is strongly flexed at the level of the midbrain, creating a near right angle between the fore- and hindbrain. These data highlight an unexpected diversity of endocranial size and morphology in NMT, features that are usually considered conservative in this group.

Nestling growth and development in the brown falcon, Falco berigora: an improved ageing formula and field-based method of sex determination

2003 ◽  
Vol 30 (4) ◽  
pp. 411 ◽  
Author(s):  
Paul G. McDonald
Keyword(s):  
Wing Length ◽  
Accurate Determination ◽  
Small Sample ◽  
Ecological Interactions ◽  
Nestling Development ◽  
Morphological Criteria ◽  
Confounding Variables ◽  
Before And After ◽  
First Time

The accurate determination of nestling age and sex is an important tool for studies that examine life-history traits and ecological interactions. Despite the widespread distribution of the brown falcon, Falco berigora, in Australia, morphological criteria for sexing nestlings of this species have yet to be published and nestling development has not been intensively studied. While an ageing formula for the species exists, the small sample from which it was derived precluded appropriate statistical assessment of independence problems and other potentially confounding variables such as hatch order and sex. This study used a larger sample of free-living nestlings to account for these factors and found the most reliable measure for ageing nestlings to be wing length. Wing length increased linearly with chick age, independent of seven other potentially confounding factors examined. Ageing formulae based on wing length before and after remiges emerge are presented. In addition, an accurate test for determining nestling sex at banding age, based on tarsus width, is proposed. Nestling chronology of this species is also described in detail for the first time. Nestling development was similar to that described for other Falconiformes; however, the chronology of nestling development was too variable to be useful in assigning chick age. Despite this, within 6 days of the eldest chick hatching the relative brightness of down and the degree to which chicks' eyes had opened were useful in assigning hatch order amongst nestlings with similar wing lengths.

scholarly journals The East Flanders Prospective Twin Study

2007 ◽  
Vol 10 (S1) ◽  
pp. 1-2
Author(s):  
Robert Derom
Keyword(s):  
Twin Study ◽  
Accurate Determination ◽  
Monozygotic Twins ◽  
Population Based ◽  
Multiple Births ◽  
Fetal Membranes ◽  
Same Sex ◽  
First Time ◽  
Duration Of Gestation

AbstractThe East Flanders Prospective Twin Survey, started in 1964, realised for the first time a population-based register of all multiple births in the Belgian Province of East Flanders, characterized by the systematic examination of the placenta and the accurate determination of zygosity based on blood groups, DNA and structure of fetal membranes. For decades, it has been the only register to include chorionicity in same-sex pairs of twins, an irreplaceable tool allowing almost certain diagnosis of monozygosity and the timing of the division of the zygote.in monozygotic twins. We showed that twins and triplets are far from being an homogenised group and demonstrated differences between these groups important enough to introduce these variables in the standard methodology of twin research. Examples are: Weinberg rule, sex ratio and duration of gestation.

scholarly journals SO<sub>2</sub> Layer Height retrieval from Sentinel-5 Precursor/TROPOMI using FP_ILM

2019 ◽  
Author(s):  
Pascal Hedelt ◽  
Dmitry S. Efremenko ◽  
Diego G. Loyola ◽  
Robert Spurr ◽  
Lieven Clarisse
Keyword(s):  
Accurate Determination ◽  
Volcanic Eruptions ◽  
Critical Parameters ◽  
Retrieval Algorithm ◽  
Layer Height ◽  
Precise Knowledge ◽  
Learning Machine ◽  
The Impact ◽  
First Time

Abstract. Precise knowledge of the location and height of the volcanic SO2 plumes is essential for accurate determination of SO2 emitted by volcanic eruptions for aviation control applications, but so far very time-consuming to retrieve from UV satellite data. The SO2 height is furthermore one of the most critical parameters that determine the impact on the climate. We have developed an extremely fast yet accurate SO2 layer height retrieval algorithm using the Full-Physics Inverse Learning Machine (FP_ILM) algorithm, which, for the first time, is applied to TROPOMI aboard Sentinel-5 Precursor. In this work we demonstrate the ability of the FP_ILM algorithm to retrieve layer heights in near-real time applications with an accuracy of better than 2 km for SO2 total columns larger than 20 DU and show SO2 layer height results for selected volcanic eruptions.

scholarly journals Use of Ga for mass bias correction for the accurate determination of copper isotope ratio in the NIST SRM 3114 Cu standard and geological samples by MC-ICPMS

2016 ◽  
Vol 31 (1) ◽  
pp. 280-287 ◽  
Author(s):  
QingHua Hou ◽  
Lian Zhou ◽  
Shan Gao ◽  
Ting Zhang ◽  
Lanping Feng ◽  
...  
Keyword(s):  
Bias Correction ◽  
Isotope Ratio ◽  
Accurate Determination ◽  
Geological Samples ◽  
Copper Isotope ◽  
Correction Model ◽  
Mass Bias ◽  
First Time ◽  
Determination Of Copper

The absolute determination of the Cu isotope ratio in NIST SRM 3114 based on a regression mass bias correction model is performed for the first time with NIST SRM 944 Ga as the calibrant.

FP_ILM: Extremely fast volcanic SO2 plume height retrieval based on S5P/TROPOMI data using inverse learning machines

2020 ◽  
Author(s):  
Dmitry Efremenko ◽  
Pascal Hedelt ◽  
Diego Loyola ◽  
Robert Spurr
Keyword(s):  
Accurate Determination ◽  
Volcanic Eruptions ◽  
Plume Height ◽  
Neural Network Approach ◽  
Layer Height ◽  
Learning Machines ◽  
Novel Method ◽  
Learning Machine ◽  
First Time

&lt;p&gt;We present here a novel method for the precise and extremely fast retrieval of volcanic SO2 layer height (LH) based on S5P/TROPOMI data. We have developed the Full-Physics Inverse Learning Machine (FP_ILM) algorithm using a combined principal components analysis (PCA) and neural network approach (NN) to extract the information about the volcanic SO2 LH from high-resolution UV backscatter measurement of TROPOMI aboard Sentinel-5 Precursor.&lt;/p&gt;&lt;p&gt;The SO2 LH is essential for accurate determination of SO2 emitted by volcanic eruptions. So far UV based SO2 plume height retrieval algorithms are very time-consuming and therefore not suitable for near-real-time applications. The FP_ILM approach however enables for the first time to extract the SO2 LH information in a matter of seconds for an entire S5P orbit and thus applicable in NRT application.&lt;/p&gt;&lt;p&gt;The FP_ILM SO2 LH product is developed as part of ESA&amp;#8217;s &amp;#8216;Sentinel-5p+ Innovation - SO2 Layer Height project&amp;#8217; (S5P+I: SO2 LH) project, dedicated to the generation of an SO2 LH product and its extensive verification with collocated ground- and space-born measurements.&lt;/p&gt;

scholarly journals Stellar occultations enable milliarcsecond astrometry for Trans-Neptunian objects and Centaurs

2020 ◽  
Vol 644 ◽  
pp. A40
Author(s):  
F. L. Rommel ◽  
F. Braga-Ribas ◽  
J. Desmars ◽  
J. I. B. Camargo ◽  
J. L. Ortiz ◽  
...  
Keyword(s):  
Accurate Determination ◽  
Topographic Features ◽  
Stellar Occultation ◽  
Stellar Occultations ◽  
Object Center ◽  
Celestial Reference System ◽  
Lower Limits ◽  
First Time

Context. Trans-Neptunian objects (TNOs) and Centaurs are remnants of our planetary system formation, and their physical properties have invaluable information for evolutionary theories. Stellar occultation is a ground-based method for studying these distant small bodies and has presented exciting results. These observations can provide precise profiles of the involved body, allowing an accurate determination of its size and shape. Aims. The goal is to show that even single-chord detections of TNOs allow us to measure their milliarcsecond astrometric positions in the reference frame of the Gaia second data release (DR2). Accurate ephemerides can then be generated, allowing predictions of stellar occultations with much higher reliability. Methods. We analyzed data from various stellar occultation detections to obtain astrometric positions of the involved bodies. The events published before the Gaia era were updated so that the Gaia DR2 stellar catalog is the reference, thus providing accurate positions. Events with detection from one or two different sites (single or double chord) were analyzed to determine the event duration. Previously determined sizes were used to calculate the position of the object center and its corresponding error with respectto the detected chord and the International Celestial Reference System propagated Gaia DR2 star position. Results. We derive 37 precise astrometric positions for 19 TNOs and four Centaurs. Twenty-one of these events are presented here for the first time. Although about 68% of our results are based on single-chord detection, most have intrinsic precision at the submilliarcsecond level. Lower limits on the diameter of bodies such as Sedna, 2002 KX14, and Echeclus, and also shape constraints on 2002 VE95, 2003 FF128, and 2005 TV189 are presented as valuable byproducts. Conclusions. Using the Gaia DR2 catalog, we show that even a single detection of a stellar occultation allows improving the object ephemeris significantly, which in turn enables predicting a future stellar occultation with high accuracy. Observational campaigns can be efficiently organized with this help, and may provide a full physical characterization of the involved object, or even the study of topographic features such as satellites or rings.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

Fast calibration of CBED patterns for quantitative analysis

1993 ◽  
Vol 51 ◽  
pp. 674-675
Author(s):  
M.A. Gribelyuk ◽  
M. Rühle
Keyword(s):  
Reciprocal Lattice ◽  
Accurate Determination ◽  
Incident Beam ◽  
Crystal Thickness ◽  
Structure Model ◽  
Beam Direction ◽  
Transmitted Beam ◽  
Reciprocal Vector ◽  
On Line

A new method is suggested for the accurate determination of the incident beam direction K, crystal thickness t and the coordinates of the basic reciprocal lattice vectors V1 and V2 (Fig. 1) of the ZOLZ plans in pixels of the digitized 2-D CBED pattern. For a given structure model and some estimated values Vest and Kest of some point O in the CBED pattern a set of line scans AkBk is chosen so that all the scans are located within CBED disks.The points on line scans AkBk are conjugate to those on A0B0 since they are shifted by the reciprocal vector gk with respect to each other. As many conjugate scans are considered as CBED disks fall into the energy filtered region of the experimental pattern. Electron intensities of the transmitted beam I0 and diffracted beams Igk for all points on conjugate scans are found as a function of crystal thickness t on the basis of the full dynamical calculation.

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