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Ancient human migrations provide the critical genetic background to historical and contemporary human demographic patterns. However, our ability to infer past human migration events, especially those that occurred over rapid timescales, is often limited. A key example is the peopling of Polynesia, where the timing is relatively well defined, but the exact routes taken during the final stages and the source populations are not. Here, we discuss the technical limitations of current methods for inferring rapid human migration events, using the final stages of Polynesian migration as an example. We also introduce a promising new proxy method to infer human migrations--patterns of bacterial evolution within ancient dental calculus (calcified plaque). While we focus on Polynesia, this method should be applicable to other past migrations, enhancing our understanding of human prehistory and revealing the crucial events that shaped it. [ABSTRACT FROM AUTHOR]

Long bone fractures are a concern in long-duration exploration missions (LDEM) where crew autonomy will exceed the current Low Earth Orbit paradigm. Current crew selection assumptions require extensive complete training and competency testing prior to flight for off-nominal situations. Analogue astronauts (n = 6) can be quickly trained to address a single fracture pattern and then competently perform the repair procedure. An easy-to-use external fixation (EZExFix) was employed to repair artificial tibial shaft fractures during an inhabited mission at the Mars Desert Research Station (Utah, USA). Bone repair safety zones were respected (23/24), participants achieved 79.2% repair success, and median completion time was 50.04 min. Just-in-time training in-mission was sufficient to become autonomous without pre-mission medical/surgical/mechanical education, regardless of learning conditions (p > 0.05). Similar techniques could be used in LDEM to increase astronauts' autonomy in traumatic injury treatment and lower skill competency requirements used in crew selection. [ABSTRACT FROM AUTHOR]

Many of the millions of animals dedicated to the deities in Ancient Egypt were canids. In contrast to the rare textual sources, the abundance of skeletal remains offers the opportunity to address the question of whether wild or domestic canids were mummified. However, species identification from osteological material remains problematic because it relies on a simple qualitative appreciation or traditional biometric analyses with low discriminatory power, often paired with incomplete comparative reference samples. Here we propose a new method of identification based on cranial form using a 3D landmark–based geometric morphometric approach (GMM). We built predictive methods using a large reference sample of numerical models of crania of modern canids, including a variety of domestic breeds (N = 69, 38 different breeds) as well as feral dogs (N = 31), and all species of wild canids present in Africa or the Near East and likely to have been present in Ancient Egypt (N = 157). We then applied these methods to a sample of ancient canid remains (N = 41). We compared the effectiveness of multivariate discriminant analyses based on 3D GMM to that using traditional linear morphometric measurements (LMM) commonly taken in the field by archaeozoologists. GMM performs better than LMM in determining the domestic/wild status with cross-validation percentages reaching over 97.5%, and in determining the species among a reduced sample of wild canids with a 96.4% rate (versus 88.2% and 85.2% in LMM respectively). With 3D GMM, we detected the presence of dogs, but also African golden wolves and, for the first time, Near Eastern grey wolves among the mummies. [ABSTRACT FROM AUTHOR]

Presents a response by the author to a letter to the editor about his article on the genetic associations of pigs.

We undertook a large-scale study of Neolithic and Bronze Age human mobility on Crete using biomolecular methods (isotope analysis, DNA), with a particular focus on sites dating to the Late Bronze Age ('Late Minoan') period. We measured the strontium and sulphur isotope values of animal remains from archaeological sites around the island of Crete to determine the local baseline values. We then measured the strontium and sulphur values of humans from Late Neolithic and Bronze Age sites. Our results indicate that most of the humans have sulphur and strontium isotope values consistent with being local to Crete, showing no evidence for a wide-scale movement of people from the Greek mainland or other areas away from Crete in these time periods. However, we found four individuals from the late Bronze Age (Late Minoan III) cemetery of Armenoi with sulphur isotope values not typically found in Crete and are instead consistent with an origin elsewhere. This cemetery at Armenoi also has one of only a few examples of the newly adopted Mycenaean Linear B script on Crete found outside of the palace sites, pointing to an influence (trade and possible migration) from the mainland, which may then be the place of origin of these four individuals. DNA (mtDNA) studies of eight Late Bronze Age individuals from Armenoi have results consistent with people living in Aegean region at this time and cannot be used to distinguish between individuals from Crete ('Minoans') and the Greek mainland ['Mycenaeans']). [ABSTRACT FROM AUTHOR]

A new silicon monoxide (28Si16O) line list covering infrared, visible, and ultraviolet regions called SiOUVenIR is presented. This line list extends the infrared EBJT ExoMol line list by including vibronic transitions to the |$A\, {}^{1}\Pi$| and |$E\, {}^{1}\Sigma ^{+}$| electronic states. Strong perturbations to the |$A\, {}^{1}\Pi$| band system are accurately modelled through the treatment of six dark electronic states: |$C\, {}^{1}\Sigma ^{-}$|⁠ , |$D\, {}^{1}\Delta$|⁠ , |$a\, {}^{3}\Sigma ^{+}$|⁠ , |$b\, {}^{3}\Pi$|⁠ , |$e\, {}^{3}\Sigma ^{-}$|⁠ , and |$d\, {}^{3}\Delta$|⁠. Along with the |$X\, {}^{1}\Sigma ^{+}$| ground state, these nine electronic states were used to build a comprehensive spectroscopic model of SiO using a combination of empirical and ab initio curves, including the potential energy (PE), spin–orbit, electronic angular momentum, and (transition) dipole moment curves. The ab initio PE and coupling curves, computed at the multireference configuration interaction level of theory, were refined by fitting their analytical representations to 2617 experimentally derived SiO energy levels determined from 97 vibronic bands belonging to the X – X ,  E – X , and A – X electronic systems through the MARVEL (Measured Active Rotational–Vibrational Energy Levels) procedure. 112 observed forbidden transitions from the C – X ,  D – X ,  e – X , and d – X bands were assigned using our predictions, and these could be fed back into the MARVEL procedure. The SiOUVenIR line list was computed using published ab initio transition dipole moments for the E – X and A – X bands; the line list is suitable for temperatures up to 10 000 K and for wavelengths longer than 140 nm. SiOUVenIR is available from www.exomol.com and the CDS data base. [ABSTRACT FROM AUTHOR]

Ancient DNA analysis of human oral microbial communities within calcified dental plaque (calculus) has revealed key insights into human health, paleodemography, and cultural behaviors. However, contamination imposes a major concern for paleomicrobiological samples due to their low endogenous DNA content and exposure to environmental sources, calling into question some published results. Decontamination protocols (e.g. an ethylenediaminetetraacetic acid (EDTA) pre-digestion or ultraviolet radiation (UV) and 5% sodium hypochlorite immersion treatments) aim to minimize the exogenous content of the outer surface of ancient calculus samples prior to DNA extraction. While these protocols are widely used, no one has systematically compared them in ancient dental calculus. Here, we compare untreated dental calculus samples to samples from the same site treated with four previously published decontamination protocols: a UV only treatment; a 5% sodium hypochlorite immersion treatment; a pre-digestion in EDTA treatment; and a combined UV irradiation and 5% sodium hypochlorite immersion treatment. We examine their efficacy in ancient oral microbiota recovery by applying 16S rRNA gene amplicon and shotgun sequencing, identifying ancient oral microbiota, as well as soil and skin contaminant species. Overall, the EDTA pre-digestion and a combined UV irradiation and 5% sodium hypochlorite immersion treatment were both effective at reducing the proportion of environmental taxa and increasing oral taxa in comparison to untreated samples. This research highlights the importance of using decontamination procedures during ancient DNA analysis of dental calculus to reduce contaminant DNA. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) is an extensively studied radiotherapeutic strategy for cancer treatment. BNCT is based on irradiation of malignant tumour cells with neutrons after uptake of a 10B containing molecule. Alpha particles, locally produced by neutron irradiation kill the cancer cells. Important for ongoing research regarding cellular uptake and cytotoxicity of a large variety of 10B containing molecules is the accurate determination of boron concentrations in cell cultures. In this work, the sample preparation for quantitative inductively coupled plasma mass spectrometry (ICP-MS) analysis on cell cultures was optimized. By making use of acid digestion combined with UV digestion, low detection limits (0.4 μg L−1) and full recoveries of boron could be achieved while measurements were free of spectral and non-spectral interferences. Finally, cell-associated boron in the form of 4-borono- L -phenylalanine (L -BPA) in vascular endothelial cell cultures could be determined with ICP-MS as (1.26 ± 0.10) × 109 boron atoms per cell. The developed method can prove its importance for further BNCT research and elemental analysis of cell cultures. [ABSTRACT FROM AUTHOR]

• Plutonium, uranium and the lanthanides are separated in a single run using 1 M nitric acid followed by a gradient of oxalic acid concentrations (0.1–0.15 M) at pH 4.5 on CG5A and CS5A mixed bed ion exchange columns in less than 60 min. • The HPIC-SF-ICP-MS method offers time savings and reduces the radiation dose to the analyst compared to gravitational ion exchange chromatography (requires weeks) followed by TIMS for the analysis of spent nuclear fuel. • The HPIC-SF-ICP-MS method was found to result in linearly increasing pulse count signals over the range 1–10 µg.L−1 for Nd, 10–100 µg.L−1 for Gd, 1–10 µg.L−1 for Pu and 0.5–24 µg.L−1 for U isotopes. • Nuclide-specific mass fractions, derived from nuclide-specific concentration measurements (external calibration), for Nd (e.g. m (142Nd)/ m (Nd)) and Gd isotopes (e.g. m (152Gd)/ m (Gd)) in a Gd spent nuclear fuel were 97–103% and 90–110%, respectively, of those obtained using TIMS • Concentrations of Pu and U determined using HPIC-SF-ICP-MS were 105% and 97%, respectively, compared to their theoretical concentration in a 242Pu spiked soil sample. High-pressure ion chromatography (HPIC) was coupled with sector field inductively coupled plasma-mass spectrometry (SF-ICP-MS) to separate plutonium (Pu), uranium (U), neodymium (Nd) and gadolinium (Gd) nuclides from isobaric nuclides and to quantify them with high sensitivity. In this study, mixed bed ion exchange columns CG5A and CS5A were used, from which Pu and U were eluted first using 1 M nitric acid. The lanthanides were then separated using a gradient of 0.1–0.15 M oxalic acid with the pH adjusted to 4.5. The HPIC-SF-ICP-MS method was validated using different sample matrices, i.e. spent nuclear fuel and soil. The method was found to be repeatable and gave rise to transient signals suitable for quantification of nuclide-specific concentrations using external calibration. In terms of accuracy, the HPIC-SF-ICP-MS measurement results were in good agreement with those obtained using thermal ionization mass spectrometry (TIMS). Finally, the method provides an improvement in sample throughput (≤60 minutes per sample) and reduces exposure of the operator to radiation compared to off-line gravitational chromatography followed by TIMS. [ABSTRACT FROM AUTHOR]

A number of putative adaptations for bipedalism have been identified in the hominin spine. However, it is possible that some have been overlooked because only a few studies have used 3D and these studies have focused on cervical vertebrae. With this in mind, we used geometric morphometric techniques to compare the 3D shapes of three thoracic and two lumbar vertebrae of Homo sapiens , Pan troglodytes, Gorilla gorilla , and Pongo pygmaeus. The study had two goals. One was to confirm the existence of traits previously reported to distinguish the thoracic and lumbar vertebrae of H. sapiens from those of the great apes. The other was to, if possible, identify hitherto undescribed traits that differentiate H. sapiens thoracic and lumbar vertebrae from those of the great apes. Both goals were accomplished. Our analyses not only substantiated a number of traits that have previously been discussed in the literature but also identified four traits that have not been described before: (1) dorsoventrally shorter pedicles in the upper thoracic vertebrae; (2) dorsoventrally longer laminae in all five of the vertebrae examined; (3) longer transverse processes in the upper thoracic vertebrae; and (4) craniocaudally 'pinched' spinous process tips in all of the vertebrae examined. A review of the biomechanical literature suggests that most of the traits highlighted in our analyses can be plausibly linked to bipedalism, including three of the four new ones. As such, the present study not only sheds further light on the differences between the spines of H. sapiens and great apes but also enhances our understanding of how the shift to bipedalism affected the hominin vertebral column. [ABSTRACT FROM AUTHOR]

Hybridization has frequently been observed between wild and domestic species and can substantially impact genetic diversity of both counterparts. Geese show some of the highest levels of interspecific hybridization across all bird orders, and two of the goose species in the genus Anser have been domesticated providing an excellent opportunity for a joint study of domestication and hybridization. Until now, knowledge of the details of the goose domestication process has come from archaeological findings and historical writings supplemented with a few studies based on mitochondrial DNA. Here, we used genome-wide markers to make the first genome-based inference of the timing of European goose domestication. We also analyzed the impact of hybridization on the genome-wide genetic variation in current populations of the European domestic goose and its wild progenitor: the graylag goose (Anser anser). Our dataset consisted of 58 wild graylags sampled around Eurasia and 75 domestic geese representing 14 breeds genotyped for 33,527 single nucleotide polymorphisms. Demographic reconstruction and clustering analysis suggested that divergence between wild and domestic geese around 5,300 generations ago was followed by long-term genetic exchange, and that graylag populations have 3.2–58.0% admixture proportions with domestic geese, with distinct geographic patterns. Surprisingly, many modern European breeds share considerable (> 10%) ancestry with the Chinese domestic geese that is derived from the swan goose Anser cygnoid. We show that the domestication process can progress despite continued and pervasive gene flow from the wild form. [ABSTRACT FROM AUTHOR]

The reconstruction of diet, subsistence strategies and human-animal relationships are integral to understanding past human societies, adaptations and resilience - especially in the circumpolar Arctic. Even in relatively recent periods, climatic excursions may have posed specific challenges for hunter-gatherer groups living at latitudinal and climatic extremes, and archaeological research in Arctic North America is increasingly looking to better understand the impact of past climate change on human groups. Here, through a unique multi-proxy approach (zooarchaeology, bone technology and stable isotope analysis), we explore human subsistence strategies, adaptation and resilience at Nunalleq, a recently excavated pre-contact Yup'ik coastal site in southwest Alaska. The main phase of occupation of the site (16th-17th centuries AD) corresponds with one of the coolest periods of the Little Ice Age – a climatic interval from the early 14th century through the mid-19th associated with global and more localised cooling events. The analyses reveal a subsistence strategy centred around the exploitation of three major resources, including salmon, marine mammals and caribou, supplemented by secondary resources such as birds and medium-sized mammals. This tripartite resource base (salmon, marine mammals, caribou) is similar to that seen at other Thule-era sites in Alaska and likely permitted a flexibility in resource use in the face of changes in resource availability (and competition over resources) during the Little Ice Age. Comparison of the different datasets, however, reveals variability and nuance in the use of animals for both dietary and broader subsistence needs. While caribou represent a vital and heavily-exploited resource at Nunalleq (evident from both the zooarchaeology and the bone technology), they did not represent a key dietary resource (indicated by stable isotope data). Instead, caribou played an integral and key part as a major source of raw material, especially antler, in order to manufacture the necessary acquisition technology to exploit primary coastal resources. [ABSTRACT FROM AUTHOR]

The S1←S0 transitions of the gaseous (2-fluoroethyl)-benzene (FEB) and (2-chloroethyl)-benzene (CEB) have been investigated using a combination of two-color resonant two-photon ionization and UV-UV hole burning spectroscopy. Both anti and gauche conformers have been identified on the basis of rotational band contour analysis supported by ab initio calculations on the ground and electronically excited states. The gauche origin band of FEB at 37 673 cm-1 is redshifted 50 cm-1 relative to the corresponding anti origin, while CEB origin bands overlap at 37 646 cm-1. Relative conformational stability and populations in the jet have been estimated for both molecules, based on the intensity ratio of S1←S0 band origin transitions. These are compared with a range of related molecules with the structural motif PhCH2CH2X (X=CH3,CH2CH3,NH2,OH,COOH,CCH,CN). Theory and experimental results for FEB and CEB show repulsive interactions between the halogen substituents and the π cloud of the phenyl rings destabilizing the gauche conformers, but the preference for the anti conformers is relatively modest. The gauche conformer origins show very different hybrid character: FEB is largely b type, while CEB is an a/c hybrid in keeping with theoretically computed TM “rotations” (θelec) of -7° and -56°, respectively. This difference is attributed largely to rotation of the side chain in opposite directions about the C1Cα bond. Spectra of FEB(H2O) and CEB(H2O) single water clusters show evidence of an anti conformation in the host molecule. [ABSTRACT FROM AUTHOR]

The Rattini tribe comprises some of the most specious genera in the mammalian kingdom. Many of these species are also highly morphologically conserved. As a result, identifying Rattini tribe animals, particularly those of the Rattus genus, to species level is extremely difficult. Problems with identification of conservative morphologies, particularly of the skeleton, have led to difficulties in understanding the fossil remains and as a result the systematics of this group. Here, we apply geometric morphometrics to the first lower molar of 14 species of the Rattini tribe. We find that the morphological data present a strong phylogenetic signal. However, within Rattus, this signal is rather complex and possibly hints at rapid evolutionary shape and size changes. In modern species, it is possible to identify specimens to species level with a good degree of confidence. We find that using both size and shape together affords further confidence with identification. However, we caution against the over-reliance on size in environments with unknown species composition and climate, particularly in archaeological contexts. This approach should prove to be a useful tool for identifying fossil and sub-fossil remains, particularly where biomolecular markers are absent in circumstances of poor preservation. [ABSTRACT FROM AUTHOR]

The implementation of the one-pass-through separation technique using two stacked chromatography columns of TEVA – TRU resins for the separation of 237 Np, 241 Am, thorium, plutonium and uranium from environmental and urine samples was investigated. The sequential separation technique proved to be successful and gave similar results to those obtained when using individual separations. The analysis time was considerably improved. The amount of chemical waste was also reduced by 50% and the use of HClO 4 was avoided. The technique of ICP-MS was also investigated as a complementary technique to alpha-spectrometry. [ABSTRACT FROM AUTHOR]