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Abstract The CMS detector, including its muon system, has been operating at the CERN LHC in increasingly challenging conditions for about 15 years. The muon detector was designed to provide excellent triggering and track reconstruction for muons produced in proton–proton collisons at an instantaneous luminosity ( $$\mathcal {L}$$ L ) of $$1 \times 10^{34}$$ 1 × 10 34 cm $$^{-2}$$ - 2 s $$^{-1}$$ - 1 . During the Run 2 data-taking period (2015–2018), the LHC achieved an instantaneous luminosity of twice its design value, resulting in larger background rates and making the efficient detection of muons more difficult. While some backgrounds result from natural radioactivity, cosmic rays, and interactions of the circulating protons with residual gas in the beam pipe, the dominant source of background hits in the muon system arises from proton–proton interactions themselves. Charged hadrons leaving the calorimeters produce energy deposits in the muon chambers. In addition, high-energy particles interacting in the hadron calorimeter and forward shielding elements generate thermal neutrons, which leak out of the calorimeter and shielding structures, filling the CMS cavern. We describe the method used to measure the background rates in the various muon subsystems. These rates, in conjunction with simulations, can be used to estimate the expected backgrounds in the High-Luminosity LHC. This machine will run for at least 10 years starting in 2029 reaching an instantaneous luminosity of $$\mathcal {L} = 5 \times \text {10}^\text {34}\,\text {cm}^\text {-2}\,\text {s}^\text {-1}$$ L = 5 × 10 34 cm -2 s -1 and increasing ultimately to $$\mathcal {L} = 7.5 \times \text {10}^\text {34}\,\text {cm}^\text {-2}\,\text {s}^\text {-1}$$ L = 7.5 × 10 34 cm -2 s -1 . These background estimates have been a key ingredient for the planning and design of the muon detector upgrade.

The temporal variation of the carbonate system, air–sea CO2 fluxes, and pH is analyzed in the southern Indian Ocean, south of the polar front, based on in situ data obtained from 1985 to 2021 at a fixed station (50°40′ S–68°25′ E) and results from a neural network model that reconstructs the fugacity of CO2 (fCO2) and fluxes at monthly scale. Anthropogenic CO2 (Cant) is estimated in the water column and is detected down to the bottom (1600 m) in 1985, resulting in an aragonite saturation horizon at 600 m that migrated up to 400 m in 2021 due to the accumulation of Cant. At the subsurface, the trend of Cant is estimated at +0.53±0.01 µmol kg−1 yr−1 with a detectable increase in the trend in recent years. At the surface during austral winter the oceanic fCO2 increased at a rate close to or slightly lower than in the atmosphere. To the contrary, in summer, we observed contrasting fCO2 and dissolved inorganic carbon (CT) trends depending on the decade and emphasizing the role of biological drivers on air–sea CO2 fluxes and pH inter-annual variability. The regional air–sea CO2 fluxes evolved from an annual source to the atmosphere of 0.8 molC m−2 yr−1 in 1985 to a sink of −0.5 molC m−2 yr−1 in 2020. Over 1985–2020, the annual pH trend in surface waters of -0.0165±0.0040 per decade was mainly controlled by the accumulation of anthropogenic CO2, but the summer pH trends were modulated by natural processes that reduced the acidification rate in the last decade. Using historical data from November 1962, we estimated the long-term trend for fCO2, CT, and pH, confirming that the progressive acidification was driven by the atmospheric CO2 increase. In 59 years this led to a diminution of 11 % for both aragonite and calcite saturation state. As atmospheric CO2 is expected to increase in the future, the pH and carbonate saturation state will decrease at a faster rate than observed in recent years. A projection of future CT concentrations for a high emission scenario (SSP5-8.5) indicates that the surface pH in 2100 would decrease to 7.32 in winter. This is up to −0.86 lower than pre-industrial pH and −0.71 lower than pH observed in 2020. The aragonite undersaturation in surface waters would be reached as soon as 2050 (scenario SSP5-8.5) and 20 years later for a stabilization scenario (SSP2-4.5) with potential impacts on phytoplankton species and higher trophic levels in the rich ecosystems of the Kerguelen Islands area.

Total alkalinity (AT) and dissolved inorganic carbon (CT) in the oceans are important properties with respect to understanding the ocean carbon cycle and its link to global change (ocean carbon sinks and sources, ocean acidification) and ultimately finding carbon-based solutions or mitigation procedures (marine carbon removal). We present a database of more than 44 400 AT and CT observations along with basic ancillary data (spatiotemporal location, depth, temperature and salinity) from various ocean regions obtained, mainly in the framework of French projects, since 1993. This includes both surface and water column data acquired in the open ocean, coastal zones and in the Mediterranean Sea and either from time series or dedicated one-off cruises. Most AT and CT data in this synthesis were measured from discrete samples using the same closed-cell potentiometric titration calibrated with Certified Reference Material, with an overall accuracy of ±4 µmol kg−1 for both AT and CT. The data are provided in two separate datasets – for the Global Ocean and the Mediterranean Sea (https://doi.org/10.17882/95414, Metzl et al., 2023), respectively – that offer a direct use for regional or global purposes, e.g., AT–salinity relationships, long-term CT estimates, and constraint and validation of diagnostic CT and AT reconstructed fields or ocean carbon and coupled climate–carbon models simulations as well as data derived from Biogeochemical-Argo (BGC-Argo) floats. When associated with other properties, these data can also be used to calculate pH, the fugacity of CO2 (fCO2) and other carbon system properties to derive ocean acidification rates or air–sea CO2 fluxes.

In this work, we study a Mediterranean cyclone, Helios, which took place during 9–11 February 2023 in the southeastern part of Sicily and Malta, by a multiparametric approach combining microseism results with sea state and meteorological data provided by wavemeter buoy, HF radar, hindcast maps and satellite SEVIRI images. The sub-tropical system Helios caused heavy rainfall, strong wind gusts and violent storm surges with significant wave heights greater than 5 m. We deal with the relationships between such a system and the features of microseism (the most continuous and ubiquitous seismic signal on Earth) in terms of spectral content, space–time variation of the amplitude and source locations tracked by means of two methods (amplitude-based grid search and array techniques). By comparing the location of the microseism sources and the area affected by significant storm surges derived from sea state data, we note that the microseism location results are in agreement with the real position of the storm surges. In addition, we are able to obtain the seismic signature of Helios using a method that exploits the coherence of continuous seismic noise. Hence, we show how an innovative monitoring system of the Mediterranean cyclones can be designed by integrating microseism information with other techniques routinely used to study meteorological phenomena.

Abstract The gold-standard treatment for Parkinson’s disease is levodopa (L-DOPA), which is taken orally and absorbed intestinally. L-DOPA must reach the brain intact to exert its clinical effect; peripheral metabolism by host and microbial enzymes is a clinical management issue. The gut microbiota is altered in PD, with one consistent and unexplained observation being an increase in Bifidobacterium abundance among patients. Recently, certain Bifidobacterium species were shown to have the ability to metabolize L-tyrosine, an L-DOPA structural analog. Using both clinical cohort data and in vitro experimentation, we investigated the potential for commensal Bifidobacteria to metabolize this drug. In PD patients, Bifidobacterium abundance was positively correlated with L-DOPA dose and negatively with serum tyrosine concentration. In vitro experiments revealed that certain species, including B. bifidum, B. breve, and B. longum, were able to metabolize this drug via deamination followed by reduction to the compound 3,4-dihydroxyphenyl lactic acid (DHPLA) using existing tyrosine-metabolising genes. DHPLA appears to be a waste product generated during regeneration of NAD +. This metabolism occurs at low levels in rich medium, but is significantly upregulated in nutrient-limited minimal medium. Discovery of this novel metabolism of L-DOPA to DHPLA by a common commensal may help inform medication management in PD.

In the field of sustainability, hydrogen (H2) is considered a clean fuel and a renewable energy source with no pollutant emissions. The production of H2 by water electrolysis is well-known among the scientific community. Still, alkaline electrolysis represents a challenging process and requires expensive materials have to be avoided in order to lower the impact of H2 production. This work deals with the production of copper (Cu) and nickel (Ni) nanoparticles (NPs) as catalysts for alkaline water splitting reactions. These NPs are synthesized using the pulsed laser ablation in liquid involving the ablation of Cu and Ni targets in methanol and ethanol. The morphological, structural, and compositional properties of the obtained NPs are studied. Then, a low amount of NPs-based catalyst (∼1μg/cm2) was loaded onto a nickel foam substrate and tested for both alkaline Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER). The best performance at 10 mA cm−2, in terms of overpotential (η), for OER was shown by Ni NPs, η = 327 mV, while for the HER, Cu NPs reached η = 211 mV at 10 mA cm−2 in aqueous 1M KOH. The ultra-low amount of the catalyst material makes these electrodes challenging in terms of mass activity [up to 14 A/mg at 10 mA cm−2] compared to the state of the art. In addition, the correlation between overpotential and the availability of electrons at the surface of the catalyst for H2 production was studied by using Mott–Schottky analysis.

The Global Ocean Data Analysis Project (GLODAP) is a synthesis effort providing regular compilations of surface-to-bottom ocean biogeochemical bottle data, with an emphasis on seawater inorganic carbon chemistry and related variables determined through chemical analysis of seawater samples. GLODAPv2.2022 is an update of the previous version, GLODAPv2.2021 (Lauvset et al., 2021). The major changes are as follows: data from 96 new cruises were added, data coverage was extended until 2021, and for the first time we performed secondary quality control on all sulfur hexafluoride (SF6) data. In addition, a number of changes were made to data included in GLODAPv2.2021. These changes affect specifically the SF6 data, which are now subjected to secondary quality control, and carbon data measured on board the RV Knorr in the Indian Ocean in 1994–1995 which are now adjusted using certified reference material (CRM) measurements made at the time. GLODAPv2.2022 includes measurements from almost 1.4 million water samples from the global oceans collected on 1085 cruises. The data for the now 13 GLODAP core variables (salinity, oxygen, nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity, pH, chlorofluorocarbon-11 (CFC-11), CFC-12, CFC-113, CCl4, and SF6) have undergone extensive quality control with a focus on systematic evaluation of bias. The data are available in two formats: (i) as submitted by the data originator but converted to World Ocean Circulation Experiment (WOCE) exchange format and (ii) as a merged data product with adjustments applied to minimize bias. For the present annual update, adjustments for the 96 new cruises were derived by comparing those data with the data from the 989 quality-controlled cruises in the GLODAPv2.2021 data product using crossover analysis. SF6 data from all cruises were evaluated by comparison with CFC-12 data measured on the same cruises. For nutrients and ocean carbon dioxide (CO2) chemistry comparisons to estimates based on empirical algorithms provided additional context for adjustment decisions. The adjustments that we applied are intended to remove potential biases from errors related to measurement, calibration, and data handling practices without removing known or likely time trends or variations in the variables evaluated. The compiled and adjusted data product is believed to be consistent to better than 0.005 in salinity, 1 % in oxygen, 2 % in nitrate, 2 % in silicate, 2 % in phosphate, 4 µmol kg−1 in dissolved inorganic carbon, 4 µmol kg−1 in total alkalinity, 0.01–0.02 in pH (depending on region), and 5 % in the halogenated transient tracers. The other variables included in the compilation, such as isotopic tracers and discrete CO2 fugacity (fCO2), were not subjected to bias comparison or adjustments. The original data, their documentation, and DOI codes are available at the Ocean Carbon and Acidification Data System of NOAA NCEI (https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/GLODAPv2_2022/, last access: 15 August 2022). This site also provides access to the merged data product, which is provided as a single global file and as four regional ones – the Arctic, Atlantic, Indian, and Pacific oceans – under https://doi.org/10.25921/1f4w-0t92 (Lauvset et al., 2022). These bias-adjusted product files also include significant ancillary and approximated data, which were obtained by interpolation of, or calculation from, measured data. This living data update documents the GLODAPv2.2022 methods and provides a broad overview of the secondary quality control procedures and results.

Intro: A weekly-based service was hypothesized as feasible and usable for surveillance, to monitoring cases in Long-Term Care Facilities (LTCFs) in the SARS-CoV-2 emergency in Italy. Methods: A web-based platform was set-up at the Italian National Institute of Health (ISS) at mid-2020. Protocols were validated and people trained to guarantee the delivery of a reliable weekly report to the Reference person of each participating Region, including the most relevant SARS-CoV-2 data and criticalities, i.e. new infections and outbreaks, deaths, hospitalization, isolations, vaccination coverage (VC), personal protective equipment and swabs. Findings: The service has been working at regimen since October 2020, available 24/7, the ISS database being fed by 7 Regions. In the period January 2021 – June 2022, 852 LCTFs (with over 22.000 residents) contributed to the service, with high adherence rate (92% on average in January 2021, 82% in March 2022 - end of emergency in Italy - and 77% in June 2022). Reports are delivered on Thursdays to inform Regional Contacts. So far, weekly data inconsistencies ranged between 6% and 10%; they were all solved by variables cross-check, comparisons with previous information, and direct interviews with the LCTFs’ operators. Regularly, data are processed to monitor trends, with focus on waves of infections. In particular, prevalence of infections reached 1.4% and SARS-CoV-2 positive deaths 0.4% in January 2021 (vaccination campaign just started), 5.5% and 0.2% respectively in January 2022 (VC ≈ 97%), 4.0% and

The characteristics of the CISE-LOCEAN seawater isotope dataset (δ18O, δ2H, referred to as δD) are presented (https://doi.org/10.17882/71186; Waterisotopes-CISE-LOCEAN, 2021). This dataset covers the time period from 1998 to 2021 and currently includes close to 8000 data entries, all with δ18O, three-quarters of them also with δD, associated with a date stamp, space stamp, and usually a salinity measurement. Until 2010, samples were analyzed by isotopic ratio mass spectrometry and since then mostly by cavity ring-down spectroscopy (CRDS). Instrumental uncertainty in this dataset is usually as low as 0.03 ‰ for δ18O and 0.15 ‰ for δD. An additional uncertainty is related to the isotopic composition of the in-house standards that are used to convert data to the Vienna Standard Mean Ocean Water (VSMOW) scale. Different comparisons suggest that since 2010 the latter have remained within at most 0.03 ‰ for δ18O and 0.20 ‰ for δD. Therefore, combining the two uncertainties suggests a standard deviation of at most 0.05 ‰ for δ18O and 0.25 ‰ for δD. For some samples, we find that there has been evaporation during collection and storage, requiring adjustment of the isotopic data produced by CRDS, based on d-excess (δD − 8×δ18O). This adjustment adds an uncertainty in the respective data of roughly 0.05 ‰ for δ18O and 0.10 ‰ for δD. This issue of conservation of samples is certainly a strong source of quality loss for parts of the database, and “small” effects may have remained undetected. The internal consistency of the database can be tested for subsets of the dataset when time series can be obtained (such as in the southern Indian Ocean or North Atlantic subpolar gyre). These comparisons suggest that the overall uncertainty of the spatially (for a cruise) or temporally (over a year) averaged data is less than 0.03 ‰ for δ18O and 0.15 ‰ for δD. However, 18 comparisons with duplicate seawater data analyzed in other laboratories or with other datasets in the intermediate and deep ocean suggest a larger scatter. When averaging the 18 comparisons done for δ18O, we find a difference of 0.082 ‰ with a standard error of 0.016 ‰. Such an average difference is expected due to the adjustments applied at LOCEAN to saline water data produced either by CRDS or isotope ratio mass spectrometry (IRMS), but the scatter found suggests that care is needed when merging datasets from different laboratories. Examples of time series in the surface North Atlantic subpolar gyre illustrate the temporal changes in water isotope composition that can be detected with a carefully validated dataset.

The decadal changes in the fugacity of CO2 (fCO2) and pH in surface waters are investigated in the southern Indian Ocean (45–57∘ S) using repeated summer observations, including measurements of fCO2, total alkalinity (AT) and total carbon (CT) collected over the period 1998–2019 in the frame of the French monitoring programme OISO (Océan Indien Service d'Observation). We used three datasets (underway fCO2, underway AT–CT and station AT–CT) to evaluate the trends of fCO2 and pH and their drivers, including the accumulation of anthropogenic CO2 (Cant). The study region is separated into six domains based on the frontal system and biogeochemical characteristics: (i) high-nutrient low-chlorophyll (HNLC) waters in the polar front zone (PFZ) and (ii) north part and (iii) south part of HNLC waters south of the polar front (PF), as well as the highly productive zones in fertilised waters near (iv) Crozet Island and (v) north and (vi) south of Kerguelen Island. Almost everywhere, we obtained similar trends in surface fCO2 and pH using the fCO2 or AT–CT datasets. Over the period 1998–2019, we observed an increase in surface fCO2 and a decrease in pH ranging from +1.0 to +4.0 µatm yr−1 and from −0.0015 to −0.0043 yr−1, respectively. South of the PF, the fCO2 trend is close to the atmospheric CO2 rise (+2.0 µatm yr−1), and the decrease in pH is in the range of the mean trend for the global ocean (around −0.0020 yr−1); these trends are driven by the warming of surface waters (up to +0.04 ∘C yr−1) and the increase in CT mainly due to the accumulation of Cant (around +0.6 µmol kg−1 yr−1). In the PFZ, our data show slower fCO2 and pH trends (around +1.3 µatm yr−1 and −0.0013 yr−1, respectively) associated with an increase in AT (around +0.4 µmol kg−1 yr−1) that limited the impact of a more rapid accumulation of Cant north of the PF (up to +1.1 µmol kg−1 yr−1). In the fertilised waters near Crozet and Kerguelen islands, fCO2 increased and pH decreased faster than in the other domains, between +2.2 and +4.0 µatm yr−1 and between −0.0023 and −0.0043 yr−1. The fastest trends of fCO2 and pH are found around Kerguelen Island north and south of the PF. These trends result from both a significant warming (up to +0.07 ∘C yr−1) and a rapid increase in CT (up to +1.4 µmol kg−1 yr−1) mainly explained by the uptake of Cant. Our data also show rapid changes in short periods and a relative stability of both fCO2 and pH in recent years at several locations both north and south of the PF, which leaves many open questions, notably the tipping point for the saturation state of carbonate minerals that remains highly uncertain. This highlights the need to maintain observations in the long-term in order to explore how the carbonate system will evolve in this region in the next decades.

We described new sea surface CO2 observations in the south-western Indian Ocean obtained in January 2020 when a strong bloom event occurred south-east of Madagascar and extended eastward in the oligotrophic Indian Ocean subtropical domain. Compared to previous years (1991–2019) we observed very low fCO2 and dissolved inorganic carbon concentrations (CT) in austral summer 2020, indicative of a biologically driven process. In the bloom, the anomaly of fCO2 and CT reached respectively −33 µatm and −42 µmol kg−1, whereas no change is observed for alkalinity (AT). In January 2020 we estimated a local maximum of air–sea CO2 flux at 27∘ S of −6.9 mmol m−2 d−1 (ocean sink) and −4.3 mmol m−2 d−1 when averaging the flux in the band 26–30∘ S. In the domain 25–30∘ S, 50–60∘ E we estimated that the bloom led to a regional carbon uptake of about −1 TgC per month in January 2020, whereas this region was previously recognized as an ocean CO2 source or near equilibrium during this season. Using a neural network approach that reconstructs the monthly fCO2 fields, we estimated that when the bloom was at peak in December 2019 the CO2 sink reached −3.1 (±1.0) mmol m−2 d−1 in the band 25–30∘ S; i.e. the model captured the impact of the bloom. Integrated in the domain restricted to 25–30∘ S, 50–60∘ E, the region was a CO2 sink in December 2019 of −0.8 TgC per month compared to a CO2 source of +0.12 (±0.10) TgC per month in December when averaged over the period 1996–2018. Consequently in 2019 this region was a stronger CO2 annual sink of −8.8 TgC yr−1 compared to −7.0 (±0.5) TgC yr−1 averaged over 1996–2018. In austral summer 2019–2020, the bloom was likely controlled by a relatively deep mixed-layer depth during the preceding winter (July–September 2019) that would supply macro- and/or micro-nutrients such as iron to the surface layer to promote the bloom that started in November 2019 in two large rings in the Madagascar Basin. Based on measurements in January 2020, we observed relatively high N2 fixation rates (up to 18 nmol N L−1 d−1), suggesting that diazotrophs could play a role in the bloom in the nutrient-depleted waters. The bloom event in austral summer 2020, along with the new carbonate system observations, represents a benchmark case for complex biogeochemical model sensitivity studies (including the N2 fixation process and iron supplies) for a better understanding of the origin and termination of this still “mysterious” sporadic bloom and its impact on ocean carbon uptake in the future.

The Global Ocean Data Analysis Project (GLODAP) is a synthesis effort providing regular compilations of surface-to-bottom ocean biogeochemical bottle data, with an emphasis on seawater inorganic carbon chemistry and related variables determined through chemical analysis of seawater samples. GLODAPv2.2021 is an update of the previous version, GLODAPv2.2020 (Olsen et al., 2020). The major changes are as follows: data from 43 new cruises were added, data coverage was extended until 2020, all data with missing temperatures were removed, and a digital object identifier (DOI) was included for each cruise in the product files. In addition, a number of minor corrections to GLODAPv2.2020 data were performed. GLODAPv2.2021 includes measurements from more than 1.3 million water samples from the global oceans collected on 989 cruises. The data for the 12 GLODAP core variables (salinity, oxygen, nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity, pH, CFC-11, CFC-12, CFC-113, and CCl4) have undergone extensive quality control with a focus on systematic evaluation of bias. The data are available in two formats: (i) as submitted by the data originator but updated to World Ocean Circulation Experiment (WOCE) exchange format and (ii) as a merged data product with adjustments applied to minimize bias. For this annual update, adjustments for the 43 new cruises were derived by comparing those data with the data from the 946 quality controlled cruises in the GLODAPv2.2020 data product using crossover analysis. Comparisons to estimates of nutrients and ocean CO2 chemistry based on empirical algorithms provided additional context for adjustment decisions in this version. The adjustments are intended to remove potential biases from errors related to measurement, calibration, and data handling practices without removing known or likely time trends or variations in the variables evaluated. The compiled and adjusted data product is believed to be consistent with to better than 0.005 in salinity, 1 % in oxygen, 2 % in nitrate, 2 % in silicate, 2 % in phosphate, 4 µmol kg−1 in dissolved inorganic carbon, 4 µmol kg−1 in total alkalinity, 0.01–0.02 in pH (depending on region), and 5 % in the halogenated transient tracers. The other variables included in the compilation, such as isotopic tracers and discrete CO2 fugacity (fCO2), were not subjected to bias comparison or adjustments. The original data, their documentation, and DOI codes are available at the Ocean Carbon Data System of NOAA NCEI (https://www.ncei.noaa.gov/access/ocean-carbon-data-system/oceans/GLODAPv2_2021/, last access: 7 July 2021). This site also provides access to the merged data product, which is provided as a single global file and as four regional ones – the Arctic, Atlantic, Indian, and Pacific oceans – under https://doi.org/10.25921/ttgq-n825 (Lauvset et al., 2021). These bias-adjusted product files also include significant ancillary and approximated data and can be accessed via https://www.glodap.info (last access: 29 June 2021). These were obtained by interpolation of, or calculation from, measured data. This living data update documents the GLODAPv2.2021 methods and provides a broad overview of the secondary quality control procedures and results.

The aquaculture industry can constitute an important source of waste in the environment. In atoll lagoons of French Polynesia, among the materials used by pearl farmers, shade-mesh collectors can release toxic substances and are responsible of microplastics production. With the aim of providing a less polluting alternative, we performed in situ tests comparing reusable plate collectors and shade-mesh collectors during 16 months. Plate collectors were significantly more efficient for spat collection, especially after the first 6 months of immersion (P

Purpose: Civic education is a central mission of public schools, and deeper learning of civics--learning that is complex and adaptive--is the goal. However, assessment of deeper civic learning is limited. Therefore, we aimed to develop an assessment model and test of deeper learning in the common high school civics course taught across the U.S. Design/methodology/approach: Using Design-Based Implementation Research (DBIR), the assessment model and test were iteratively researched and revised by a team of researchers and teachers across seven years and multiple settings. Findings: Results of validity and reliability studies show that the model and test are promising tools for assessing deeper civic learning. Research limitations/implications: Additional research is warranted to refine the test-development process, design alternative test forms, and adapt the model to other social studies courses. Practical implications: We suggest ways to use this assessment model to assess learning in civics and other social studies subjects.