Radiocarbon (C) is essential for creating chronologies to study the timings and drivers of pivotal events in human history and the Earth system over the past 55,000 years. It is also a fundamental proxy for investigating solar processes, including the potential of the Sun for extreme activity. Until now, fluctuations in past atmospheric C levels have limited the dating precision possible using radiocarbon.
View Article and Find Full Text PDFObjective: We conducted a large ( = 204) randomized, clinical trial to test the efficacy of parent-child interaction therapy (PCIT) on observed parenting, two key drivers of maladaptive parenting-self-regulation and social cognitions, and child behavior outcomes in a sample of child welfare-involved families.
Method: Participants were randomly assigned to standard PCIT ( = 120) or services-as-usual (SAU; = 84). The sample was characterized by low household income, significant exposures to adverse childhood experiences, and substance abuse.
Six infant human teeth and 112 animal tooth pendants from Borsuka Cave were identified as the oldest burial in Poland. However, uncertainties around the dating and the association of the teeth to the pendants have precluded their association with an Upper Palaeolithic archaeological industry. Using <67 mg per tooth, we combined dating and genetic analyses of two human teeth and six herbivore tooth pendants to address these questions.
View Article and Find Full Text PDFPhilos Trans A Math Phys Eng Sci
November 2023
Radiocarbon (C) is a critical tool for understanding the global carbon cycle. During the Anthropocene, two new processes influenced C in atmospheric, land and ocean carbon reservoirs. First, C-free carbon derived from fossil fuel burning has diluted C, at rates that have accelerated with time.
View Article and Find Full Text PDFWe present new C results measured on subfossil Scots Pines recovered in the eroded banks of the Drouzet watercourse in the Southern French Alps. About 400 new C ages have been analysed on 15 trees sampled at annual resolution. The resulting ΔC record exhibits an abrupt spike occurring in a single year at 14 300-14 299 cal yr BP and a century-long event between 14 and 13.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
March 2023
The last glacial cycle provides the opportunity to investigate large changes in the Atlantic Meridional Overturning Circulation (AMOC) beyond the small fluctuations evidenced from direct measurements. Paleotemperature records from Greenland and the North Atlantic show an abrupt variability, called Dansgaard-Oeschger (DO) events, which is associated with abrupt changes of the AMOC. These DO events also have Southern Hemisphere counterparts via the thermal bipolar seesaw, a concept describing the meridional heat transport leading to asynchronous temperature changes between both hemispheres.
View Article and Find Full Text PDFWe present the results of a multi-disciplinary investigation on a deciduous human tooth (Pradis 1), recently recovered from the Epigravettian layers of the Grotte di Pradis archaeological site (Northeastern Italian Prealps). Pradis 1 is an exfoliated deciduous molar (Rdm), lost during life by an 11-12-year-old child. A direct radiocarbon date provided an age of 13,088-12,897 cal BP (95% probability, IntCal20).
View Article and Find Full Text PDFThe climate history of the Sahara desert during recent millennia is obscured by the near absence of natural climate archives, hampering insight in the relative importance of southerly (tropical) and northerly (midlatitude) weather systems at submillennial time scales. A new lake sediment record from Ounianga Serir oasis in northern Chad, spanning the Late Holocene without interruption, confirms that immediately before ca 4200 years ago, the Sahara experienced an episode of hyperaridity even more extreme than today's desert climate. The hypersaline terminal lake which formed afterwards never desiccated during the late Holocene due to continuous inflow of fossil groundwater, yet its water balance was sensitive to temporal variation in local rainfall and lake surface evaporation.
View Article and Find Full Text PDFRadiocarbon (C), as a consequence of its production in the atmosphere and subsequent dispersal through the carbon cycle, is a key tracer for studying the Earth system. Knowledge of past C levels improves our understanding of climate processes, the Sun, the geodynamo, and the carbon cycle. Recently updated radiocarbon calibration curves (IntCal20, SHCal20, and Marine20) provide unprecedented accuracy in our estimates of C levels back to the limit of the C technique (~55,000 years ago).
View Article and Find Full Text PDFThe Rhône-Loire metropolitan areas' 2020/21 respiratory syncytial virus (RSV) epidemic was delayed following the implementation of non-pharmaceutical interventions (NPI), compared with previous seasons. Very severe lower respiratory tract infection incidence among infants ≤ 3 months decreased twofold, the proportion of cases among children aged > 3 months to 5 years increased, and cases among adults > 65 years were markedly reduced. NPI appeared to reduce the RSV burden among at-risk groups, and should be promoted to minimise impact of future RSV outbreaks.
View Article and Find Full Text PDFThe new radiocarbon calibration curve (IntCal20) allows us to calculate the gradient of the relationship between C age and calendar age over the past 55 millennia before the present (55 ka BP). The new gradient curve exhibits a prolonged and prominent maximum between 48 and 40 ka BP during which the radiocarbon clock runs almost twice as fast as it should. This radiocarbon time dilation is due to the increase in the atmospheric C/C ratio caused by the C production rise linked to the transition into the Laschamp geomagnetic excursion centered around 41 ka BP.
View Article and Find Full Text PDFThe Middle to Upper Palaeolithic transition in Europe witnessed the replacement and partial absorption of local Neanderthal populations by Homo sapiens populations of African origin. However, this process probably varied across regions and its details remain largely unknown. In particular, the duration of chronological overlap between the two groups is much debated, as are the implications of this overlap for the nature of the biological and cultural interactions between Neanderthals and H.
View Article and Find Full Text PDFThe stratigraphy at Bacho Kiro Cave, Bulgaria, spans the Middle to Upper Palaeolithic transition, including an Initial Upper Palaeolithic (IUP) assemblage argued to represent the earliest arrival of Upper Palaeolithic Homo sapiens in Europe. We applied the latest techniques in C dating to an extensive dataset of newly excavated animal and human bones to produce a robust, high-precision radiocarbon chronology for the site. At the base of the stratigraphy, the Middle Palaeolithic (MP) occupation dates to >51,000 yr BP.
View Article and Find Full Text PDFWe analysed changes in mean annual air temperature (MAAT), vegetation and biomass burning on a long and continuous lake-peat sediment record from the Colônia basin, southeastern Brazil, examining the responses of a wet tropical rainforest over the last 180 ka. Stronger southern atmospheric circulation up to the latitude of Colônia was found for the penultimate glacial with lower temperatures than during the last glacial, while strengthening of the South American summer monsoon (SASM) circulation started during the last interglacial and progressively enhanced a longer wet summer season from 95 ka until the present. Past MAAT variations and fire history were possibly modulated by eccentricity, although with signatures which differ in average and in amplitude between the last 180 ka.
View Article and Find Full Text PDFThe genus is composed of tick-borne obligate intracellular gram-negative alphaproteobacteria of the family Anaplasmataceae. includes important pathogens affecting canids (, , and ), rodents (), and ruminants (). , an closely related to , was initially reported in Canada and Brazil.
View Article and Find Full Text PDFFront Cell Infect Microbiol
July 2020
Ticks transmit the most diverse array of disease agents and harbor one of the most diverse microbial communities. Major progress has been made in the characterization of the taxonomic profiles of tick microbiota. However, the functional profiles of tick microbiome have been comparatively less studied.
View Article and Find Full Text PDFBackground: University of Oklahoma Health Sciences Center has offered Interdisciplinary Training Program (ITP) for Child Abuse and Neglect since 1987. However, there are limited evaluations on multidisciplinary/interprofessional training for early professionals in the field of child abuse and neglect.
Objective: This study aimed to examine the effects of the ITP on young professionals in developing their careers and taking leadership roles in the field of child abuse and neglect.
Carbohydrates are among the most abundant organic molecules in both aquatic and terrestrial ecosystems; however, very few studies have addressed their isotopic signature using compound-specific isotope analysis, which provides additional information on their origin (δC) and fate (ΔC). In this study, semi-preparative liquid chromatography with refractive index detection (HPLC-RI) was employed to produce pure carbohydrate targets for subsequent offline δC and ΔC isotopic analysis. δC analysis was performed by elemental analyzer-isotope ratio mass spectrometer (EA-IRMS) whereas ΔC analysis was performed by an innovative measurement procedure based on the direct combustion of the isolated fractions using an elemental analyzer coupled to the gas source of a mini carbon dating system (AixMICADAS).
View Article and Find Full Text PDFis a tick-borne pathogen affecting cattle, cervids, and dogs, and it is closely related to the monocytotropic pathogen Here, we announce the draft genome sequence of strain Cuiabá, isolated from a naturally infected calf from Santo Antônio do Leverger, Mato Grosso, Brazil.
View Article and Find Full Text PDFRadiocarbon dating archaeological bone typically requires 300-1000 mg material using standard protocols. We report the results of reducing sample size at both the pretreatment and C measurement stages for eight archaeological bones spanning the radiocarbon timescale at different levels of preservation. We adapted our standard collagen extraction protocol specifically for <100 mg bone material.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
March 2019
Recently, it has been confirmed that extreme solar proton events can lead to significantly increased atmospheric production rates of cosmogenic radionuclides. Evidence of such events is recorded in annually resolved natural archives, such as tree rings [carbon-14 (C)] and ice cores [beryllium-10 (Be), chlorine-36 (Cl)]. Here, we show evidence for an extreme solar event around 2,610 years B.
View Article and Find Full Text PDFAnaplasma phagocytophilum is a bacterial pathogen mainly transmitted by Ixodes ricinus ticks in Europe. It infects wild mammals, livestock, and, occasionally, humans. Roe deer are considered to be the major reservoir, but the genotypes they carry differ from those that are found in livestock and humans.
View Article and Find Full Text PDFThe human impact on natural habitats is increasing the complexity of human-wildlife interactions and leading to the emergence of infectious diseases worldwide. Highly successful synanthropic wildlife species, such as rodents, will undoubtedly play an increasingly important role in transmitting zoonotic diseases. We investigated the potential for recent developments in 16S rRNA amplicon sequencing to facilitate the multiplexing of the large numbers of samples needed to improve our understanding of the risk of zoonotic disease transmission posed by urban rodents in West Africa.
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