Oxygen isotopes trace the origins of Earth's earliest continental crust.

Much of the current volume of Earth's continental crust had formed by the end of the Archaean eon1 (2.5 billion years ago), through melting of hydrated basaltic rocks at depths of approximately 25-50 kilometres, forming sodic granites of the tonalite-trondhjemite-granodiorite (TTG) suite2-6. However, the geodynamic setting and processes involved are debated, with fundamental questions arising, such as how and from where the required water was added to deep-crustal TTG source regions7,8. In addition, there have been no reports of voluminous, homogeneous, basaltic sequences in preserved Archaean crust that are enriched enough in incompatible trace elements to be viable TTG sources5,9. Here we use variations in the oxygen isotope composition of zircon, coupled with whole-rock geochemistry, to identify two distinct groups of TTG. Strongly sodic TTGs represent the most-primitive magmas and contain zircon with oxygen isotope compositions that reflect source rocks that had been hydrated by primordial mantle-derived water. These primitive TTGs do not require a source highly enriched in incompatible trace elements, as 'average' TTG does. By contrast, less sodic 'evolved' TTGs require a source that is enriched in both water derived from the hydrosphere and also incompatible trace elements, which are linked to the introduction of hydrated magmas (sanukitoids) formed by melting of metasomatized mantle lithosphere. By concentrating on data from the Palaeoarchaean crust of the Pilbara Craton, we can discount a subduction setting6,10-13, and instead propose that hydrated and enriched near-surface basaltic rocks were introduced into the mantle through density-driven convective overturn of the crust. These results remove many of the paradoxical impediments to understanding early continental crust formation. Our work suggests that sufficient primordial water was already present in Earth's early mafic crust to produce the primitive nuclei of the continents, with additional hydrated sources created through dynamic processes that are unique to the early Earth.

Effect of a comfort scale compared with a pain numerical rate scale on opioids consumption in postanaesthesia care unit: the COMFORT study.

BACKGROUND: The way that pain is assessed in the PACU could impact on postoperative pain and analgesic consumption. However, there is currently no evidence to support this speculation. The authors hypothesised that using a comfort scale reduces postoperative opioid consumption when compared with a standard numerical rating scale (NRS) to evaluate pain in the PACU. METHODS: In this cluster-randomised trial, patients were assessed using either a comfort scale (comfort group) or a pain NRS (NRS group). The primary outcome was the opioid consumption in the PACU. The main secondary outcomes were postoperative pain, nausea and vomiting, length of stay in the PACU, and satisfaction. RESULTS: Of 885 randomised patients, 860 were included in the analysis. Opioid consumption in the PACU was comparable in the comfort and NRS groups (median [interquartile range [IQR] 0 (0-5) vs 0 (0-6); P=0.2436), irrespective of the type of surgical procedure. The majority of patients did not need any postoperative opioid (59% in the comfort group and 56% in the NRS group, P=0.2260). There was no difference in postoperative pain, nausea and vomiting, time to reach an Aldrete score ≥9 after extubation, and global satisfaction. CONCLUSIONS: Using a comfort scale to assess pain in the PACU did not spare any opioid compared with use of a standard NRS. Further studies focusing on patients at risk of increased postoperative opioid consumption are necessary. CLINICAL TRIAL REGISTRATION: NCT05234216.

Exposure of cattle to tick-borne encephalitis virus in the historical endemic zone in north-eastern France.

BACKGROUND: Tick-borne encephalitis (TBE) is a severe human neuroinfection caused by TBE virus (TBEV). TBEV is transmitted by tick bites and by the consumption of unpasteurized dairy products from infected asymptomatic ruminants. In France, several food-borne transmission events have been reported since 2020, raising the question of the level of exposure of domestic ungulates to TBEV. In this study, our objectives were (i) to estimate TBEV seroprevalence and quantify antibodies titres in cattle in the historical endemic area of TBEV in France using the micro virus neutralisation test (MNT) and (ii) to compare the performance of two veterinary cELISA kits with MNT for detecting anti-TBEV antibodies in cattle in various epidemiological contexts. A total of 344 cattle sera from four grid cells of 100 km² in Alsace-Lorraine (endemic region) and 84 from western France, assumed to be TBEV-free, were investigated. RESULTS: In Alsace-Lorraine, cattle were exposed to the virus with an overall estimated seroprevalence of 57.6% (95% CI: 52.1-62.8%, n = 344), varying locally from 29.9% (95% CI: 21.0-40.0%) to 92.1% (95% CI: 84.5-96.8%). Seroprevalence did not increase with age, with one- to three-year-old cattle being as highly exposed as older ones, suggesting a short-life duration of antibodies. The proportion of sera with MNT titres lower than 1:40 per grid cell decreased with increased seroprevalence. Both cELISA kits showed high specificity (> 90%) and low sensitivity (less than 78.1%) compared with MNT. Sensitivity was lower for sera with neutralising antibodies titres below 1:40, suggesting that sensitivity of these tests varied with local virus circulation intensity. CONCLUSIONS: Our results highlight that cattle were highly exposed to TBEV. Screening strategy and serological tests should be carefully chosen according to the purpose of the serological study and with regard to the limitations of each method.

Development of a cell culture-based method for detecting infectious tick-borne encephalitis virus (TBEV) in milk products.

Tick-borne encephalitis outbreaks have been reported in Europe after consumption of raw milk products from infected animals. While molecular methods are commonly used in viral foodborne outbreak investigations due to their sensitivity, specificity and rapidity, there are very few methods to detect infectious tick-borne encephalitis virus (TBEV) in milk products for routine use/analyses. To address this gap, we developed a cell culture-based method to detect infectious TBEV in artificially contaminated raw goat milk and raw goat cheese, and evaluated the sensitivity of TBEV infectivity assays. Raw goat milk samples were spiked with TBEV to achieve inoculation levels ranging from 106 to 100 TCID50/mL, and Faisselle and Tomme cheese samples were spiked so their TBEV concentrations ranged from 9.28 × 105 to 9.28 × 101 TCID50 per 2.5g. To detect infectious TBEV, Vero cells were infected by raw goat milk. For cheese samples, after homogenisation and membrane filtration, Vero cells were infected with samples adsorbed on the filter (method A) or with samples eluted from the filter (method B). After 5 days, cytopathic effects (CPEs) were observed and TBEV replication in Vero cells was confirmed by an increase in the number of genome copies/mL that were detected in cell supernatant. Infected Vero cells exhibited CPEs for both milk and cheese samples. Infectious TBEV was detected to 103 TCID50/mL in raw milk samples and to 9.28 × 101 TCID50 from Faisselle samples using both methods A and B. For Tomme samples, method A was able to detect TBEV to 9.28 × 102 TCID50/2.5g and method B to 9.28 × 103 TCID50/2.5g. The number of positive samples detected was slightly higher with method A than with method B. To conclude, this qualitative cell culture-based method can detect infectious TBEV artificially inoculated into raw milk and cheese; it should be further evaluated during foodborne outbreak investigations to detect infectious TBEV from naturally contaminated milk and cheese.

The internal structure and geodynamics of Mars inferred from a 4.2-Gyr zircon record.

Combining U-Pb ages with Lu-Hf data in zircon provides insights into the magmatic history of rocky planets. The Northwest Africa (NWA) 7034/7533 meteorites are samples of the southern highlands of Mars containing zircon with ages as old as 4476.3 ± 0.9 Ma, interpreted to reflect reworking of the primordial Martian crust by impacts. We extracted a statistically significant zircon population (n = 57) from NWA 7533 that defines a temporal record spanning 4.2 Gyr. Ancient zircons record ages from 4485.5 ± 2.2 Ma to 4331.0 ± 1.4 Ma, defining a bimodal distribution with groupings at 4474 ± 10 Ma and 4442 ± 17 Ma. We interpret these to represent intense bombardment episodes at the planet's surface, possibly triggered by the early migration of gas giant planets. The unradiogenic initial Hf-isotope composition of these zircons establishes that Mars's igneous activity prior to ∼4.3 Ga was limited to impact-related reworking of a chemically enriched, primordial crust. A group of younger detrital zircons record ages from 1548.0 ± 8.8 Ma to 299.5 ± 0.6 Ma. The only plausible sources for these grains are the temporally associated Elysium and Tharsis volcanic provinces that are the expressions of deep-seated mantle plumes. The chondritic-like Hf-isotope compositions of these zircons require the existence of a primitive and convecting mantle reservoir, indicating that Mars has been in a stagnant-lid tectonic regime for most of its history. Our results imply that zircon is ubiquitous on the Martian surface, providing a faithful record of the planet's magmatic history.

Prognosis value of partial arterial oxygen pressure in patients with septic shock subjected to pre-hospital invasive ventilation.

OBJECTIVE: Mechanical ventilation can help improve the prognosis of septic shock. While adequate delivery of oxygen to the tissue is crucial, hyperoxemia may be deleterious. Invasive out-of-hospital ventilation is often promptly performed in life-threatening emergencies. We propose to determine whether the arterial oxygen pressure (PaO2) at the intensive care unit (ICU) admission is associated with mortality in patients with septic shock subjected to pre-hospital mechanical ventilation. METHODS: We performed a monocentric retrospective observational study on 77 patients. PaO2 was measured at ICU admission. The primary outcome was mortality at day 28 (D28). RESULTS: Forty-nine (64%) patients were included. The mean PaO2 at ICU admission was 153 ±â€¯77 and 202 ±â€¯82 mm Hg for alive and deceased patients respectively. Mortality concerned 18% of patients for PaO2 < 100, 25% for 100 < PaO2 < 150 and 57% for a PaO2 > 150 mm Hg. PaO2 was significantly associated with mortality at D28 (p = 0.04). Using propensity score analysis including SOFA score, pre-hospital duration, lactate, and prehospital fluid volume expansion, association with mortality at D28 only remained for PaO2 > 150 mm Hg (p = 0.02, OR [CI95] = 1.59 [1.20-2.10]). CONCLUSIONS: In this study, we report a significant association between hyperoxemia at ICU admission and mortality in patients with septic shock subjected to pre-hospital invasive mechanical ventilation. The early adjustment of the PaO2 should be considered for these patients to avoid the toxic effects of hyperoxemia. However, blood gas analysis is hard to get in a prehospital setting. Consequently, alternative and feasible measures are needed, such as pulse oximetry, to improve the management of pre-hospital invasive ventilation.

Quantification of indicator and pathogenic bacteria in manures and digestates from three agricultural biogas plants over a one-year period.

Interest in the conversion of manure in biogas via anaerobic digestion (AD) is growing, but questions remain about the biosafety of digestates. For a period of one year, we monitored the impact of three mesophilic agricultural biogas plants (BPs) mainly fed with pig manure (BP1, BP3) or bovine manure (BP2) on the physicochemical parameters, the composition of the microbial community and the concentration of bacteria (E. coli, enterococci, Salmonella, Campylobacter, Listeria monocytogenes, Clostridium perfringens, Clostridium botulinum and Clostridioides difficile). The BP2 digestate differed from those of the two other BPs with a higher nitrogen content, more total solids and greater abundance of Clostridia MBA03 and Disgonomonadacea. Persistence during digestion ranked from least to most, was: Campylobacter (1.6 to >2.9 log10 reduction, according to the BP) < E. coli (1.8 to 2.2 log10) < Salmonella (1.1 to 1.4 log10) < enterococci (0.2 to 1.2 log10) and C. perfringens (0.2 to 1 log10) < L. monocytogenes (-1.2 to 1.6 log10) < C. difficile and C. botulinum (≤0.5 log10). No statistical link was found between the reduction in the concentration of the targeted bacteria and the physicochemical and operational parameters likely to have an effect (NH3, volatile fatty acids and total solids contents, hydraulic retention time, presence of co-substrates), underlining the fact that the fate of the bacteria during mesophilic digestion depends on many interacting factors. The reduction in concentrations varied significantly over the sampling period, underlining the need for longitudinal studies to estimate the impact of AD on pathogenic microorganisms.

Nanoparticle suspensions from carbon-rich fluid make high-grade gold deposits.

Economic gold deposits result from a 100- to 10,000-fold enrichment in gold relative to crustal background. In hydrothermal systems, this enrichment is achieved through the transport and accumulation of metals via deeply sourced fluids to a site of deposition. However, the generally low metal solubility of Au in aqueous solutions in orogenic systems requires additional processes in order to explain high-grade gold formation. Reports of Au nanoparticles in high-grade gold veins infer that their formation is linked to mineralisation. However, processes leading to nanoparticle nucleation and deposition remain poorly understood. Here we show that formation of metal nanoparticles (Au, AuAg, Cu, Ag2O) is one of the essential contributors to efficient and focused gold deposition. We report systematic and previously unrecognized metal nanoparticles preserved in amorphous silica and/or carbonic phases in five high-grade deposits. The association of metal, silica and carbonic phases helps to constrain the multiple reactive processes involved in Au, Cu and Ag metallogenesis and formation of high-grade gold mineralisation.

Impact and habitability scenarios for early Mars revisited based on a 4.45-Ga shocked zircon in regolith breccia.

After formation of a primordial crust, early impacts influenced when habitable conditions may have occurred on Mars. Martian meteorite Northwest Africa (NWA) 7034 is a regolith breccia that contains remnants of the earliest Martian crust. The paucity of shock deformation in NWA 7034 was previously cited as recording a decline in giant impacts by 4.48 billion years and evidence for habitable Mars by 4.2 billion years ago. We present new evidence of high-pressure shock effects in a 4.45-billion year-old zircon from the matrix of NWA 7034. The zircon contains {112} shock twins formed in the central uplift of a complex impact structure after 4.45 billion years and records impact pressures of 20 to 30 gigapascals. The zircon represents the highest shock level reported in NWA 7034 and paired rocks and provides direct physical evidence of large impacts, some potentially life-affecting, that persisted on Mars after 4.48 billion years.

Asymptomatic Carriage of C. botulinum Type D/C in Broiler Flocks as the Source of Contamination of a Massive Botulism Outbreak on a Dairy Cattle Farm.

In winter 2018, a massive type D/C cattle botulism outbreak occurred on a mixed dairy and broiler farm in France. An investigation was conducted based on the hypothesis of asymptomatic carriage in poultry. We set out to identify the source of contamination of the dairy cattle and to monitor the contamination of broilers over time, including the hatchery delivering chicks to the farm. Environmental samples were collected on the farm during the cattle outbreak (n = 40), after the outbreak for three successive broiler flocks (n = 128), and once in the hatchery delivering the chicks (n = 58). These samples were analyzed using real-time PCR after an enrichment step to detect Clostridium botulinum type D/C. The results showed contamination in the manure from the broilers raised just before the onset of the cattle outbreak (5 + /5), as well as in some of the components of the cattle ration (3 + /17). This latter contamination is likely due to the use of the same tractor bucket to remove litter from the poultry house and to prepare the cattle ration on the same day. Contamination monitoring over several months revealed continuous asymptomatic carriage in the broilers (4 + /20 and 17 + /20 cloacal swabs in 2 successive flocks), a persistence of C. botulinum type D/C in the ventilation system of the poultry house (8 + /14), and contamination of the equipment coming from the hatchery used for delivering the chicks (3 + /18). Further investigations conducted in the hatchery demonstrated contamination in the hatchery by C. botulinum type D/C (6 + /58). Comparison of samples using a multilocus variable number tandem repeat analysis showed the same profile for samples collected on broilers, cattle and in the hatchery. This study highlighted the crucial role of the implementation of biosecurity measures in mixed farms to avoid cross-contamination between production units given the potential asymptomatic carriage of poultry. This study also revealed the contamination of the poultry hatchery. Further investigations are required to better understand the role of hatcheries in the epidemiology of animal botulism.

Questing tick abundance in urban and peri-urban parks in the French city of Lyon.

BACKGROUND: In Europe, ticks are responsible for the transmission of several pathogens of medical importance, including bacteria of the Borrelia burgdorferi (s.l.) complex, the agents of Lyme borreliosis. In France, the Auvergne Rhône-Alpes region is considered a hot spot for human tick-borne pathogen infections, with an estimated annual rate of 156 cases of Lyme borreliosis per 100,000 inhabitants. Although several studies have assessed the abundance of ticks in rural areas, little consideration has been given thus far to urban green spaces in France. METHODS: This study aimed to estimate tick abundance in three parks, two urban (U1, U2) and one peri-urban (PU), in and around the city of Lyon (France). A forest in a rural area was used as a control (C). Tick sampling campaigns were performed in each site in April, May, June, July, and October 2019 using the dragging method. One hundred transects of 10 m2 each were randomly chosen in each park in places frequented by humans. The sampling sessions were carried out under semi-controlled abiotic conditions. Ticks were stored in 70% ethanol and identified to species and developmental stage under a light microscope using morphological keys. RESULTS: A total of seven ticks (nymphs and adults) were collected in the two urban parks (six in U1 and one in U2), while 499 ticks were sampled in the peri-urban park. Of the 506 ticks collected, 504 were identified as Ixodes ricinus, one as Dermacentor marginatus, and one as Ixodes frontalis. In the peri-urban park, ticks were mainly collected under the forest cover and at forest edges. Tick density under forest cover was 7.1 times higher in the control site than in the peri-urban park throughout the survey period. CONCLUSIONS: This study confirmed the presence of ticks in all of the parks surveyed, although their occurrence in the urban parks was very rare compared to the peri-urban park and the control site. These results should serve as a basis for the implementation of preventive measures.

Experimental infection of pigs by Salmonella Derby, S. Typhimurium and monophasic variant of S. Typhimurium: Comparison of colonization and serology.

Salmonella serovars Derby, Typhimurium and the monophasic variant of Salmonella Typhimurium are the most frequently isolated serovars in pigs in France. To compare the excretion patterns, seroconversion to Salmonella and contamination of the organs of pigs inoculated with strains of all three serovars, we conducted an experimental trial with 28 SPF piglets. Four were used as a negative control, while the other 24 were divided equally into three groups. Each group was inoculated at 7 weeks of age with a different strain: S. Derby (SDb), S. Typhimurium (ST), and the monophasic variant of S. Typhimurium (mST). Fecal and blood samples were collected twice a week up until necropsy, on 21 days post-inoculation (DPI) for half of each group and 49 DPI for the remaining piglets. During necropsy, the tonsils, mesenteric lymph nodes and various intestinal contents were collected from each pig. Salmonella bacteria were quantified in CFU/g by a bacteriological method, and levels of Salmonella antibodies were measured using an ELISA Kit. Piglets inoculated with mST continuously excreted Salmonella in their feces throughout the trial. For each of the other serovars, one piglet was Salmonella-negative on one DPI. The quantity of Salmonella excreted was statistically different between the group inoculated with ST and mST (p < 0.05), but no differences were found between the other serovars. The tonsils, cecum and jejunum were the most contaminated organs in all groups. Seroconversion for all the piglets was completed by different DPI: 28 for ST, 31 for mST and 38 for SDb. No major differences were found in terms of excretion and colonization among the studied serovars.

A Case Report of a Botulism Outbreak in Beef Cattle Due to the Contamination of Wheat by a Roaming Cat Carcass: From the Suspicion to the Management of the Outbreak.

We report a botulism outbreak in Charolais cattle fed with wheat flour contaminated by Clostridium botulinum type C and the management of the outbreak at each step from the clinical suspicion to the cleaning and disinfection operations. Diagnosis was based on typical suggestive clinical signs and detection of C. botulinum type C using real-time PCR in samples collected from three young affected bulls. All young exposed bulls and cows (18 animals) eventually died, but three young bulls and one cow were recovering when it was decided to euthanize them. C. botulinum type C was detected in the liver of these four animals. Analysis of the ration components demonstrated that wheat flour, wheat, and the mill used to make flour were positive for C. botulinum type C. A dead cat positive for C. botulinum type C was discovered in the silo where wheat grain was stored and was considered the source of contamination. The cat's entire body was found mummified, well preserved, and not rotting in the silo. Specific measures, in particular, vaccination of the rest of the herd and cleaning and disinfection operations, were implemented to prevent any recurrence of the outbreak. The presence of wild animal carcasses in feed harboring anaerobic conditions like silage, in particular during harvesting, are known to be at risk for the initiation of a botulism outbreak. This outbreak is a reminder that the presence of an animal carcass in feed, regardless of the kind of feed and whenever the contamination occurs, either during harvesting or storage, is sufficient to induce a botulism outbreak.

Transient neurological deficit due to a misplacement of central venous catheter despite ultrasound guidance and ultrasound assistance.

Central venous catheters (CVC) are frequently used in intensive care units (ICU), with a low incidence of complications, most of them being of mechanical origin and occurring during the insertion of the catheter. To avoid such complications, "ultrasound guidance" and "ultrasound assistance" are recommended. Nevertheless, even with trained and experienced physicians, mechanical complications of IJV access such as carotid punctures are still reported. We report the case of a 75-year-old woman, admitted into the ICU for CVC insertion due to impossibility of peripheral venous access. About 12 hours after the procedure, the patient presented a neurological deficit. The cervical and thoracic CT scan showed a transfixing path of the catheter from the left IJV into the left common carotid artery, with distal extremity of the catheter localized in the ascending aorta. The catheter was removed, and thereafter the neurological deficit immediately and definitely disappeared. Onset of a neurological deficit after CVC insertion into the IJV, regardless the time of occurrence after the procedure, should suggest complication due to the CVC insertion, even if procedure was uneventful and chest radiography confirmed the apparent accurate position of CVC.