A freshwater diet-derived 14C reservoir effect at the Stone Age sites in the Iron Gates gorge

From the 17th International Radiocarbon Conference held in Jerusalem, Israel, June 18-23, 2000.Human bones from single inhumation burials and artifacts made from terrestrial mammal (ungulate) bone found in direct association with the skeletons were obtained from the Stone Age site of Schela Cladovei situated just below the Iron Gates Gorge of the River Danube. The results of stable isotope analyses of the human bone collagen are consistent with a heavy dependence on aquatic protein while radiocarbon dating of the samples reveals an offset of 300-500 years between the two sample types, indicating a freshwater reservoir effect in the human bone samples. Since protein consumption is by far the major source of nitrogen in the human diet we have assumed a linear relationship between delta-15N and the level of aquatic protein in each individual's diet and derived a calibration for 14C age offset versus delta-15N which has been applied to a series of results from the site at Lepenski Vir within the gorge. The corrected 14C ages (7310-6720 BP) are now consistent with the previous 14C age measurements made on charcoal from related contexts (7360-6560 BP). In addition, the data indicate a change from a primarily aquatic to a mixed terrestrial/aquatic diet around 7100 BP and this may be argued as supporting a shift from Mesolithic to Neolithic. This study also has wider implications for the accurate dating of human bone samples when the possibility exists of an aquatic component in the dietary protein and strongly implies that delta-15N analysis should be undertaken routinely when dating human bones.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Preliminary site assessment for ground monitoring of a complex landslide along I-40 in Roane County, Tennessee

In-ground slope monitoring is an essential part of landslide early warning systems. Precise movement data from borehole monitors can detect emerging hazards near critical infrastructure. Typically, monitoring is done with inclinometers, but lower-cost alternatives have emerged which have yet to be tested in Tennessee. Time domain reflectometry (TDR) records magnitudes and depths of movements along a buried coaxial cable. When paired with a remote data logger, TDR can wirelessly transmit high resolution movement data in real time, making it promising for landslide early warning systems. Tennessee Department of Transportation (TDOT) has proposed a one-year feasibility study to test TDR for use in unstable soil slopes near highways. The study area is a well-known landslide site along Interstate 40 in Roane County, TN. Careful siting of borehole instrumentation is crucial for accurate monitoring. The goal of this study is to optimize TDR installation, with three specific aims: (i) evaluate landslide morphology, (ii) pinpoint locations and depths with greatest movement, and (iii) assess spatiotemporal patterns across the site. Statistical analysis of prior data from 13 inclinometers showed ongoing slope movement over the 21-acre complex landslide. Spatial interpolation suggested an asymmetrical failure surface with both shallow and deep motion. Space-time cube analysis indicated varying movement rates and timing across the site, suggesting separate landslide bodies. Based on these results, three optimal borehole depths and locations were proposed for TDR instruments. This analysis will ensure accuracy in tests of TDR for early warning system feasibility in Tennessee

Electrochemistry of molecules in nanotubes

The work presented in this thesis describes the use of carbon nanotubes as both electrodes and containers for electrochemical reactions. The cyclic voltammetry (CV) and coulometry of metallocenes, half-sandwich complexes, fullerene containing molecules and organic molecules are presented. The nanoscale confinement in carbon nanotubes affects both the spatial confinement and the electronic properties of the guest-molecule. Encapsulation of molecules can also lead to a change in the electronic properties of the host-nanotube. The specific nature of the interactions between the guest-molecule and nanotube was investigated by the encapsulation of molecules inside carbon nanotubes followed by measurements of the electrochemical redox processes of the guest-molecules using CV and coulometry. The internal diameter of the single-walled carbon nanotubes (SWNT) used throughout this thesis is commensurate with the size of single molecules, which leads to the mechanism of reactions being influenced by the limited space around the guest-molecule. This can also lead to the products of some electrochemical reactions being templated by the nanotube’s shape and size. Furthermore, the unique electronic band structure of carbon nanotubes affects interactions of certain guest-molecules with the internal wall of the nanotube, the magnitude and type of interaction associated with different guest-molecules depends on the energy of the highest occupied molecular orbital (HOMO) of the guest-molecule as well as the electronic states and the Fermi level of the host-nanotube. The effect of this interaction on both the guest-molecule and host-nanotube is determined using CV, coulometry and linear sweep voltammetry (LSV). An example of this is the encapsulation of cobaltocene and ferrocene in SWNT, a strong interaction between cobaltocene (Co(Cp)2) and the nanotube is observed, but only a weak interaction is observed between ferrocene (Fe(Cp)2) and the nanotube through changes in the cyclic voltammetry (CV) of the encapsulated molecules. Additionally, these interactions affect the electronic bands of the nanotube due to the injection of electrons into the nanotube conduction band. Using coulometry and LSV, the magnitude of this charge injection into the nanotube and whether the nanotube will be metallic or semiconducting is determined. The redox processes of the electrochemically induced ligand exchange of CpMeMn(CO)3 inside single-walled carbon nanotubes is probed, investigating how a reaction that relies on both an external nucleophile and the elimination of a ligand is changed when confined in the nanoscale channel of the nanotube. Finally, the use of nanotubes as a reaction vessel for an internal electrochemical reaction is investigated, whereby the nanotubes pre-arrange the reactant molecule in position for particular reactions. The confinement enables an electrochemical reaction that wouldn’t occur in bulk solution and the carbon nanotube templates a new product inaccessible by other means. The electronic and steric interactions of nanotubes with guest-molecules change the properties of the host and the guest, thus leading to exciting new materials and new products that cannot be synthesised otherwise. The results presented in this thesis demonstrate the significance of the electrochemistry of molecules in nanotubes for fundamental chemistry and provide a new methodology of making novel products by utilising carbon nanotubes as reaction vessels and nanoscale electrodes

Enhanced 'In-situ' catalysis via microwave selective heating: catalytic chain transfer polymerisation

An extremely facile, single stage, ‘in-situ’, Catalytic Chain Transfer Polymerisation (CCTP) process has been identified, where the optimal polymerisation process was shown to depend upon a combination of catalyst characteristics (i.e. solubility, sensitivity, activity) and the method of heating applied. In comparison to the current benchmark catalyst, the preparation of which is only about 40 % efficient, this represents a significant increase in waste prevention/atom efficiency and removes the need for organic solvent. It was also shown possible to significantly reduce the overall ‘in-situ’ reaction cycle time by adopting different processing strategies in order to minimise energy use. The application of microwave heating was demonstrated to overcome system diffusion/dilution issues and result in rapid, ‘in-situ’ catalyst formation. This allowed processing times to be minimised by enabling a critical concentration of the species susceptible to microwave selective heating to dominate the heat and mass transfer involved

Illicit COVID-19 products online: A mixed-method approach for identifying and preventing online health risks

© 2023 Catalani et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Aims: The COVID-19 pandemic triggered a demand for vaccines, cures, and the need of related documentation for travel, work and other purposes. Our project aimed to identify the illicit availability of such products across the Dark Web Markets (DWMs). Methods: A retrospective search for COVID-19 related products was carried out across 118 DWMs since the start of the pandemic (March 2020-October 2021). Data on vendors as well as advertised goods such as asking price, marketplace, listed date were collected and further validated through additional searches on the open web to verify the information relating to specific marketplaces. Both quantitative and qualitative methods were used for data analysis. Results: Forty-two listings of unlicenced COVID-19 cures and vaccination certificates were identified across 8 marketplaces sold by 25 vendors with significant variation in prices. The listings were found to be geographically specific and followed the progression of the pandemic in terms of availability. Correlations between vendor portfolios of COVID-19 products and variety of goods of other illicit nature such as illegal weaponry, medication/drugs of abuse also emerged from our analysis. Conclusion: This study is one of the first attempts to identify the availability of unlicenced COVID-19 products on DWMs. The easy accessibility to vaccines, fake test certificates and hypothetical/illegal cures poses serious health risks to (potential) buyers due to the uncontrolled nature of such products. It also exposes buyers to an unwanted contact with vendors selling a variety of other dangerous illicit goods. Further monitoring and regulatory responses should be implemented to protect the health and safety of citizens especially at times of global crisis.Peer reviewe

Cross-sectional and longitudinal assessment of cognitive development in Williams syndrome

Williams syndrome (WS) is a rare genetic syndrome. As with all rare syndromes, obtaining adequately powered sample sizes is a challenge. Here we present legacy data from seven UK labs, enabling the characterisation of cross-sectional and longitudinal developmental trajectories of verbal and non-verbal development in the largest sample of individuals with WS to-date. In Study 1, we report cross-sectional data from between N=102 and N=209 children and adults with WS on measures of verbal and non-verbal ability. In Study 2, we report longitudinal data from N=17 to N=54 children and adults with WS who had been tested on at least three timepoints on these measures. Data support the WS characteristic cognitive profile of stronger verbal than non-verbal ability, and shallow developmental progression for both domains. Both cross-sectional and longitudinal data demonstrate steeper rates of development in the child participants than the adolescent and adults in our sample. Cross-sectional data indicate steeper development in verbal than non-verbal ability, and that individual differences in the discrepancy between verbal and non-verbal ability are largely accounted for by level of intellectual functioning. A diverging developmental discrepancy between verbal and non-verbal ability, whilst marginal, is not mirrored statistically in the longitudinal data. Cross-sectional and longitudinal data are discussed with reference to validating cross-sectional developmental patterns using longitudinal data and the importance of individual differences in understanding developmental progression

Profiling the vendors of COVID‐19 related product on the Darknet: An observational study

/© 2023 The Author(s). Published by Elsevier Ltd on behalf of International Society for the Study of Emerging Drugs. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)BACKGROUND: In a time of unprecedented global change, the COVID-19 pandemic has led to a surge in demand of COVID-19 vaccines and related certifications. Mainly due to supply shortages, counterfeit vaccines, fake documentation, and alleged cures to illegal portfolios, have been offered on darkweb marketplaces (DWMs) with important public health consequences. We aimed to profile key DWMs and vendors by presenting some in-depth case studies.METHODS: A non-systematic search for COVID-19 products was performed across 118 DWMs. Levels of activity, credibility, content, COVID-19 product listings, privacy protocols were among the features retrieved. Open web fora and other open web sources were also considered for further analysis of both functional and non functional DWMs. Collected data refers to the period between January 2020 and October 2021.RESULTS: A total of 42 relevant listings sold by 24 vendors across eight DWMs were identified. Four of these markets were active and well-established at the time of the study with good levels of credibility. COVID-19 products were listed alongside other marketplace content. Vendors had a trusted profile, communicated in English language and accepted payments in cryptocurrencies (Monero or Bitcoin). Their geographical location included the USA, Asia and Europe. While COVID-19 related goods were mostly available for regional supply, other listings were also shipped worldwide.INTERPRETATION: Findings emerging from this study rise important questions about the health safety of certain DWMs activities and encourage the development of targeted interventions to overcome such new and rapidly expanding public health threats.FUNDING: CovSaf, National Research centre on Privacy, Harm Reduction and Adversarial Influence Online (REPHRAIN), Commonwealth Fund.Peer reviewe

Neonatal stroke surveillance study protocol in the United Kingdom and Republic of Ireland

Abstract Neonatal stroke is a devastating condition that causes brain injury in babies and often leads to lifelong neurological impairment. Recent prospective population studies of neonatal stroke are lacking. Neonatal strokes are different from those in older children and adults. A better understanding of its aetiology, current management, and outcomes could reduce the burden of this rare condition. The study aims to explore the incidence and 2 year outcomes of neonatal stroke across an entire population in the UK and Republic of Ireland. This is an active national surveillance study using a purpose-built integrated case notification-data collection online platform. Over a 13 month period, with a potential 6 month extension, clinicians will notify neonatal stroke cases presenting in the first 90 days of life electronically via the online platform monthly. Clinicians will complete a primary questionnaire via the platform detailing clinical information, including neuroimaging, for analysis and classification. An outcome questionnaire will be sent at 2 years of age via the platform. Appropriate ethics and regulatory approvals have been received. The neonatal stroke study represents the first multinational population surveillance study delivered via a purpose-built integrated case notification-data collection online platform and data safe haven, overcoming the challenges of setting up the study

Improved Techniques for the Surveillance of the Near Earth Space Environment with the Murchison Widefield Array

In this paper we demonstrate improved techniques to extend coherent processing intervals for passive radar processing, with the Murchison Widefield Array. Specifically, we apply a two stage linear range and Doppler migration compensation by utilising Keystone Formatting and a recent dechirping method. These methods are used to further demonstrate the potential for the surveillance of space with the Murchison Widefield Array using passive radar, by detecting objects orders of magnitude smaller than previous work. This paper also demonstrates how the linear Doppler migration methods can be extended to higher order compensation to further increase potential processing intervals.Comment: Presented at the 2019 IEEE Radar Conference in Boston earlier this yea