48 research outputs found
Luminescence Dating of Sediments from Ancient Irrigation Features, and Associated with Occupation of the Hinterland around Anuradhapura, Sri Lanka
This study supports a new investigation into the development and decline of irrigation and associated human activity in the Anuradhapura Hinterland, Sri Lanka (section 2). Optically stimulated luminescence (OSL) age determinations have been made for a variety of sediments from bund and tank systems, irrigation channels, palaeosols and ceramic scatter horizons in the Anuradhapura hinterland (section 3). The geomorphological and archaeological significance of the age determinations has been reviewed in the light of the luminescence results and the samples’ depositional contexts, to constrain the deposition/formation dates of the sampled sediments integrate the OSL results with independent archaeological and historical expectations (section 6).
A total of 26 age determinations were made (section 5.3). Dose rate determinations were made using thick source beta counting, high-resolution gamma spectrometry, field gamma spectrometry, measured water contents and calculated cosmic dose rates (sections 4.2.1, 5.1). Equivalent dose determinations were made (sections 4.2.2, 5.2) using the OSL signals from sand sized grains of quartz separated from each sample. Dose rates ranged from 1.1 to 5.0 mGy/a, equivalent dose values ranged from 0.29 to 33 Gy. Age estimates for these samples ranged from 0.14 to 13 ka, the average being 2.9 ka ± 3.1 (section 5.3). Uncertainties on the age estimates were commonly 7% at
one standard error.
The OSL age estimates from the largest bund and some ceramic scatter sites were greater than 2000 BC. This is older than expected on archaeological grounds and further investigation of these sites may be warranted. The OSL results from the other samples in the present study date bund construction during the initial urbanisation of Anuradhapura c. 400BC, coincident with the major Nachchaduwa bund construction c. 300AD, and in the Late Iron Age / Early Mediaeval period c. 600AD. They date abandonment of one irrigation channel to the 8th Century AD and its infill up to the late 10th Century when Anuradhapura was finally sacked. A further 8 age estimates, from silts and colluvium, relate to the collapse of infrastructure in the Anuradhapura hinterland during the 10th century and continued landscape response during the 11th century, followed by the lead-in to restoration of the irrigation system during the colonial era
Transport in the metropolitan counties: current performance and future prospects. - Vol. 2: Evidence
Carbon footprint of Power-to-X derived dimethyl ether using the sorption enhanced DME synthesis process
Dimethyl ether (DME) could have a promising future as a sustainable diesel fuel replacement as it requires only relatively minor engine modifications. It can be produced from renewable H2 and captured CO2 using Power-to-X technologies. To gain support through the EU Renewable Energy Directive, the production and use of CO2-derived DME as a fuel needs to produce emission savings of at least 70% over the petrodiesel alternative. This study assesses the carbon footprint of producing DME via the sorption-enhanced DME synthesis (SEDMES) process and using it as a transport fuel, compared to producing and using fossil-based petrodiesel. The cradle-to-grave (well-to-wheel) carbon footprint of using DME as a transport fuel is found to be 77% lower than for petrodiesel, if offshore wind power is used for H2 synthesis and DME production. If renewable energy is also used for CO2 capture and waste heat is used for the DME production and purification steps, the DME carbon footprint has the potential to be over 90% lower than that of the fossil-fuel comparator
Zooplankton community responses to the mixture of imazethapyr with imazapic and bispyribac-sodium herbicides under rice paddy water conditions
Effect of a Perioperative, Cardiac Output-Guided Hemodynamic Therapy Algorithm on Outcomes Following Major Gastrointestinal Surgery A Randomized Clinical Trial and Systematic Review
Importance: small trials suggest that postoperative outcomes may be improved by the use of cardiac output monitoring to guide administration of intravenous fluid and inotropic drugs as part of a hemodynamic therapy algorithm.Objective: to evaluate the clinical effectiveness of a perioperative, cardiac output–guided hemodynamic therapy algorithm.Design, setting, and participants: OPTIMISE was a pragmatic, multicenter, randomized, observer-blinded trial of 734 high-risk patients aged 50 years or older undergoing major gastrointestinal surgery at 17 acute care hospitals in the United Kingdom. An updated systematic review and meta-analysis were also conducted including randomized trials published from 1966 to February 2014.Interventions: patients were randomly assigned to a cardiac output–guided hemodynamic therapy algorithm for intravenous fluid and inotrope (dopexamine) infusion during and 6 hours following surgery (n=368) or to usual care (n=366).Main outcomes and measures: the primary outcome was a composite of predefined 30-day moderate or major complications and mortality. Secondary outcomes were morbidity on day 7; infection, critical care–free days, and all-cause mortality at 30 days; all-cause mortality at 180 days; and length of hospital stay.Results: baseline patient characteristics, clinical care, and volumes of intravenous fluid were similar between groups. Care was nonadherent to the allocated treatment for less than 10% of patients in each group. The primary outcome occurred in 36.6% of intervention and 43.4% of usual care participants (relative risk [RR], 0.84 [95% CI, 0.71-1.01]; absolute risk reduction, 6.8% [95% CI, ?0.3% to 13.9%]; P?=?.07). There was no significant difference between groups for any secondary outcomes. Five intervention patients (1.4%) experienced cardiovascular serious adverse events within 24 hours compared with none in the usual care group. Findings of the meta-analysis of 38 trials, including data from this study, suggest that the intervention is associated with fewer complications (intervention, 488/1548 [31.5%] vs control, 614/1476 [41.6%]; RR, 0.77 [95% CI, 0.71-0.83]) and a nonsignificant reduction in hospital, 28-day, or 30-day mortality (intervention, 159/3215 deaths [4.9%] vs control, 206/3160 deaths [6.5%]; RR, 0.82 [95% CI, 0.67-1.01]) and mortality at longest follow-up (intervention, 267/3215 deaths [8.3%] vs control, 327/3160 deaths [10.3%]; RR, 0.86 [95% CI, 0.74-1.00]).Conclusions and relevance: in a randomized trial of high-risk patients undergoing major gastrointestinal surgery, use of a cardiac output–guided hemodynamic therapy algorithm compared with usual care did not reduce a composite outcome of complications and 30-day mortality. However, inclusion of these data in an updated meta-analysis indicates that the intervention was associated with a reduction in complication rate
The evolution of language: a comparative review
For many years the evolution of language has been seen as a disreputable topic, mired in fanciful "just so stories" about language origins. However, in the last decade a new synthesis of modern linguistics, cognitive neuroscience and neo-Darwinian evolutionary theory has begun to make important contributions to our understanding of the biology and evolution of language. I review some of this recent progress, focusing on the value of the comparative method, which uses data from animal species to draw inferences about language evolution. Discussing speech first, I show how data concerning a wide variety of species, from monkeys to birds, can increase our understanding of the anatomical and neural mechanisms underlying human spoken language, and how bird and whale song provide insights into the ultimate evolutionary function of language. I discuss the ‘‘descended larynx’ ’ of humans, a peculiar adaptation for speech that has received much attention in the past, which despite earlier claims is not uniquely human. Then I will turn to the neural mechanisms underlying spoken language, pointing out the difficulties animals apparently experience in perceiving hierarchical structure in sounds, and stressing the importance of vocal imitation in the evolution of a spoken language. Turning to ultimate function, I suggest that communication among kin (especially between parents and offspring) played a crucial but neglected role in driving language evolution. Finally, I briefly discuss phylogeny, discussing hypotheses that offer plausible routes to human language from a non-linguistic chimp-like ancestor. I conclude that comparative data from living animals will be key to developing a richer, more interdisciplinary understanding of our most distinctively human trait: language
Large-scale phenotyping of patients with long COVID post-hospitalization reveals mechanistic subtypes of disease
One in ten severe acute respiratory syndrome coronavirus 2 infections result in prolonged symptoms termed long coronavirus disease (COVID), yet disease phenotypes and mechanisms are poorly understood1. Here we profiled 368 plasma proteins in 657 participants ≥3 months following hospitalization. Of these, 426 had at least one long COVID symptom and 233 had fully recovered. Elevated markers of myeloid inflammation and complement activation were associated with long COVID. IL-1R2, MATN2 and COLEC12 were associated with cardiorespiratory symptoms, fatigue and anxiety/depression; MATN2, CSF3 and C1QA were elevated in gastrointestinal symptoms and C1QA was elevated in cognitive impairment. Additional markers of alterations in nerve tissue repair (SPON-1 and NFASC) were elevated in those with cognitive impairment and SCG3, suggestive of brain–gut axis disturbance, was elevated in gastrointestinal symptoms. Severe acute respiratory syndrome coronavirus 2-specific immunoglobulin G (IgG) was persistently elevated in some individuals with long COVID, but virus was not detected in sputum. Analysis of inflammatory markers in nasal fluids showed no association with symptoms. Our study aimed to understand inflammatory processes that underlie long COVID and was not designed for biomarker discovery. Our findings suggest that specific inflammatory pathways related to tissue damage are implicated in subtypes of long COVID, which might be targeted in future therapeutic trials
SARS-CoV-2-specific nasal IgA wanes 9 months after hospitalisation with COVID-19 and is not induced by subsequent vaccination
BACKGROUND: Most studies of immunity to SARS-CoV-2 focus on circulating antibody, giving limited insights into mucosal defences that prevent viral replication and onward transmission. We studied nasal and plasma antibody responses one year after hospitalisation for COVID-19, including a period when SARS-CoV-2 vaccination was introduced. METHODS: In this follow up study, plasma and nasosorption samples were prospectively collected from 446 adults hospitalised for COVID-19 between February 2020 and March 2021 via the ISARIC4C and PHOSP-COVID consortia. IgA and IgG responses to NP and S of ancestral SARS-CoV-2, Delta and Omicron (BA.1) variants were measured by electrochemiluminescence and compared with plasma neutralisation data. FINDINGS: Strong and consistent nasal anti-NP and anti-S IgA responses were demonstrated, which remained elevated for nine months (p < 0.0001). Nasal and plasma anti-S IgG remained elevated for at least 12 months (p < 0.0001) with plasma neutralising titres that were raised against all variants compared to controls (p < 0.0001). Of 323 with complete data, 307 were vaccinated between 6 and 12 months; coinciding with rises in nasal and plasma IgA and IgG anti-S titres for all SARS-CoV-2 variants, although the change in nasal IgA was minimal (1.46-fold change after 10 months, p = 0.011) and the median remained below the positive threshold determined by pre-pandemic controls. Samples 12 months after admission showed no association between nasal IgA and plasma IgG anti-S responses (R = 0.05, p = 0.18), indicating that nasal IgA responses are distinct from those in plasma and minimally boosted by vaccination. INTERPRETATION: The decline in nasal IgA responses 9 months after infection and minimal impact of subsequent vaccination may explain the lack of long-lasting nasal defence against reinfection and the limited effects of vaccination on transmission. These findings highlight the need to develop vaccines that enhance nasal immunity. FUNDING: This study has been supported by ISARIC4C and PHOSP-COVID consortia. ISARIC4C is supported by grants from the National Institute for Health and Care Research and the Medical Research Council. Liverpool Experimental Cancer Medicine Centre provided infrastructure support for this research. The PHOSP-COVD study is jointly funded by UK Research and Innovation and National Institute of Health and Care Research. The funders were not involved in the study design, interpretation of data or the writing of this manuscript
Luminescence Dating of Sediments Associated with Norse Agriculture from Søndre Igaliku, Greenland
This study supports a new investigation into the chronology, and the palaeoenvironmental context and consequences, of Viking settlement in Greenland (section 2). Optically stimulated luminescence (OSL) age determinations have been made for a series of sediments associated with Norse agricultural activity around the farm and church site of Søndre Igaliku, Eastern Settlement (section 3). The geomorphological and archaeological significance of the age determinations has been reviewed in the light of the luminescence results and the samples’ depositional contexts, to constrain the deposition/formation dates of the sampled sediments (section 6).
A total of 5 age determinations were made (section 5.3). Dose rate determinations were made using thick source beta counting, high-resolution gamma spectrometry, field gamma spectrometry, measured water contents and calculated cosmic dose rates (sections 4.2.1, 5.1). Equivalent dose determinations were made (sections 4.2.2, 5.2) using the OSL signals from sand sized grains of quartz separated from each sample. Dose rates ranged from 3.1 to 3.7 mGy/a, De values ranged from 2.2 to 3.2 Gy. Age estimates for these samples ranged from 0.66 to 0.94 ka, the average being 0.82 ka ± 0.11 (section 5.3). Uncertainties on the age estimates were commonly 10 % at one
standard error.
The OSL results indicate formation of soils with anthropogenic input from the 11th through into the 14th Centuries AD at Søndre Igaliku, i.e. covering the expected range of Norse settlement in the region (section 6.3). These appear to have subsequently been buried by material dating to the 12th Century, possibly reworked from coastally eroded homefields associated with the same settlement. Consideration of mechanisms for redeposition in the light of the OSL results indicates that the reworking hypothesis should be testable using soil micromorphological analysis of the microbanded layers (6 to 4). Comparison of the OSL results with 14C results on charcoal from the same sediments indicates that marine reservoir effects and wood-age may combine to produce a residual of c. 100-200 years in calibrated radiocarbon dates (section 6.3)