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Fluid and insulin treatments are the cornerstones of DKA management and indications on dosages are available. However, according to possible confounding factors, relevant data are still required to explain the different insulin dosages adopted at diabetes onset, particularly based upon insulin sensitivity.We aimed to explore whether DKA severity is related to different insulin sensitivity states, thus resulting in different insulin requirement at diabetes onset.Retrospective data from hospital records of 62 newly diagnosed children with type 1 diabetes with DKA were analyzed. The population was divided into three groups: severe, moderate, and mild DKA. Anthropometric, laboratory test, insulin, and glucose administration data were analyzed. The Glucose Infusion Rate (GIR), Insulin Infusion Rate (IIR), and GIR/IIR were calculated and used as indexes of insulin sensitivity. The area under the curve (AUC) for insulin and glucose infusion was calculated.Moving among the three groups, IIR decreased while GIR and GIR/IIR increased from severe to mild DKA group (all p 0.01). A similar trend was documented for AUC-insulin and AUC-glucose as well as AUC-glucose/AUC-insulin ratio. The Spearman correlation showed a negative correlation between pH and both IIR and AUC-Insulin as well as a positive correlation between pH and both GIR/IIR and AUC-glucose/AUC-insulin ratio.Subjects with severe DKA have a higher insulin requirement compared to those with less severe DKA. Significant differences in terms of insulin sensitivity might be documented according to the severity of DKA, which might result in tailored insulin pH requirement in children with new onset type 1 diabetes.

We investigated the continent-ocean transition (COT) structure of three main marginal seas in the western Pacific Ocean (South China Sea, Coral Sea, and Woodlark Basin) to determine the tectono-magmatic processes acting during continental breakup. The COT formed from the activity of a low-angle normal fault system localizing deformation during final rifting. Extension was contemporaneous with magmatic activity, including volcanic edifices, dikes, and sills in the distalmost parts of these basins. The COT shows a sharp juxtaposition in space and time of continental crust against igneous oceanic crust, and its overall structure differs from that of magma-poor or magma-rich passive-margin archetypes. We propose that this mode of breakup is characteristic of marginal seas due to the high extension rates imposed by kinematic forces of nearby subduction zones. Revealed in the context of marginal seas, this mode of breakup and the resulting COT structures highlight the underestimated diversity of continental breakup mechanisms.

Sponges are known for hosting diverse communities of microbial symbionts, but despite persistent interest in the sponge microbiome, most research has targeted marine sponges; freshwater sponges have been the focus of less than a dozen studies. Here, we used 16 S rRNA gene amplicon sequencing and shotgun metagenomics to characterize the microbiome of the freshwater sponge Ephydatia muelleri and identify potential indicators of sponge-microbe mutualism. Using samples collected from the Sooke, Nanaimo, and Cowichan Rivers on Vancouver Island, British Columbia, we show that the E. muelleri microbiome is distinct from the ambient water and adjacent biofilms and is dominated by Sediminibacterium, Comamonas, and unclassified Rhodospirillales. We also observed phylotype-level differences in sponge microbiome taxonomic composition among different rivers. These differences were not reflected in the ambient water, suggesting that other environmental or host-specific factors may drive the observed geographic variation. Shotgun metagenomes and metagenome-assembled genomes further revealed that freshwater sponge-associated bacteria share many genomic similarities with marine sponge microbiota, including an abundance of defense-related proteins (CRISPR, restriction-modification systems, and transposases) and genes for vitamin B12 production. Overall, our results provide foundational information on the composition and function of freshwater sponge-associated microbes, which represent an important yet underappreciated component of the global sponge microbiome.

COVID-19 restriction measurements have enhanced the obesity status in the pediatric population which might further contribute to obesity-related glucose-insulin metabolism alterations. Therefore, we retrospectively compared anthropometric and OGTT data on children with obesity during the 13 years before and during the COVID-19 pandemic.Data from 741 children with obesity and overweight were retrieved and clustered into seven groups starting from year 2008-2009 until 2020-2021. Differences in anthropometric measurements and glucose/insulin metabolism were evaluated between the different groups.Children with overweight and obesity in the COVID-19 restriction group did not present increased values of SDS-Body Mass Index (BMI). Significantly higher values for Waist Circumference (WC), SDS-WC, Waist/Height ratio (WHtR), and body mass fat were detected in these children (all P 0.01). Fasting glycaemia, glucose, and insulin excursions were significantly higher compared to pre- pandemic children (all P 0.01). Insulin resistance was higher while insulin secretion was lower (all P 0.01) determining a significantly higher percentage of impaired glucose tolerance in the COVID-19 restriction group (P 0.002). Furthermore, High-Density Lipoprotein (HDL) cholesterol was significantly lower (P 0.01) and SDS for systolic and diastolic blood pressure values were significantly higher (P = 0.03 and P = 0.02, respectively).COVID-19 restriction measurements determined profound alterations in glucose and insulin metabolism in children with obesity and overweight. Urgent strategies are needed in order to reverse COVID-19 restriction measures' effects on glucose and insulin metabolism.

Measurements of ion flux-energy distribution functions at the high sheath potential of the driven electrode in a classical low-pressure asymmetric capacitively coupled plasma are technically difficult as the diagnostic device needs to float with the applied radio frequency voltage. Otherwise, the ion sampling is disturbed by the varying electric field between the grounded device and the driven electrode. To circumvent such distortions, a low-pressure plasma chamber with inverted electrode geometry, where the larger electrode is driven and the smaller electrode is grounded, has been constructed and characterized. Measurements of the ion flux-energy distribution functions with an energy-selective mass spectrometer at the high sheath potential of the grounded electrode are presented for a variety of conditions and ions. The potential for suppressing low-energy ions from resonant charge transfer collisions in the sheath by the dilution of the working gas is demonstrated. Additionally, the setup is supplemented by an inductively coupled plasma that controls the plasma density and consequently the ion flux to the substrate while the radio frequency bias controls the ion energy. At high ion energies, metal ions are detected as a consequence of the ionization of sputtered electrode material. The proposed setup opens a way to study precisely the effects of ion treatment for a variety of substrates such as catalysts, polymers, or thin films.

A mixed-methods research design with a sequential, explanatory approach was used to investigate the extent to which successful completion of integrated mathematics and science methods of instruction courses related to elementary preservice teachers’ attitudes toward and confidence in teaching integrated STEM lessons. Participants (n = 24) were enrolled in their final two semesters of a teacher preparation program at a four-year public university leading to dual certification in elementary (K-6) and special education. Quantitative data were collected using the STEM Attitudes Questionnaire and the STEM Confidence Questionnaire and administered as a pre, post, and delayed post measure. Qualitative data were obtained from focus group participants and open-ended questions added to the delayed post-measures. Results indicated an overall positive change in attitudes and confidence over the 11-month period but no statistically significant difference in the participants’ attitudes toward or confidence in teaching integrated STEM lessons. Important implications for the numerous stakeholders of STEM education are presented.

Due to demand for high performance inside and outside of the classroom, student-athletes are a unique subsection of college students. Researchers have focused on investigating protective factors, which may enhance student-athlete well-being and academic success in higher education and reduce athlete burnout. The current study examined grit as a mediator between parenting behaviors and academic success, mental health outcomes, and burnout in higher education among National Collegiate Athletic Association Division I and Division II student-athletes (N =202). Overparenting behaviors were negatively associated with psychological autonomy granting, mental health outcomes, and athlete burnout. Psychological autonomy granting behaviors were positively associated with grit and negatively associated with mental health outcomes and athlete burnout. Student-athlete grit mediated the relationship between overparenting behaviors and mental health outcomes. Clinical implications include improving student-athlete parent onboarding protocol; student-athlete psychoeducation; and preventative outreach and health promotion among athletes, athletic staff, and university practitioners. In summary, these findings suggest that parenting behaviors and grit are factors that require more attention in fostering student-athlete success.

Cognitive deficits are a core feature of schizophrenia, and impairments are present in groups at-risk for psychosis. Most at-risk studies include young adults and not younger age-groups, such as adolescents. Participants are usually help-seeking individuals, even though risk factors may also be present in non-help seeking adolescents. We aim to explore cognitive functions in a group of non-help-seeking 15-year-old adolescents at risk for psychosis compared to age- and gender matched controls, including particular focus on specific cognitive domains. Hundred participants (mean age = 15.3) were invited after completing the 14-year-old survey distributed by the Norwegian Mother-, Father- and Child Study. At-risk adolescents were selected based on high scores on 19 items assessing both psychotic experiences and anomalous self-experiences. Matched controls were selected from the same sample. Cognitive functioning was assessed using the MATRICS Consensus Cognitive Battery and IQ using Wechsler’s Abbreviated Test of Intelligence. We found that the adolescents at-risk for psychosis had significantly poorer scores than controls on the composite score of the MCCB. IQ scores were also significantly lower in the at-risk group. The results highlight general cognitive deficits as central in a group of non-help-seeking adolescents at-risk for psychosis. Results indicate that the development of cognitive impairments starts early in life in at-risk groups. It is still unclear whether specific cognitive domains, such as verbal learning, are related to psychotic symptoms or may be specifically vulnerable to symptoms of depression and anxiety.

Characterizing microorganisms and enzymes involved in lignin biodegradation in thermal ecosystems can identify thermostable biocatalysts. We integrated stable isotope probing (SIP), genome-resolved metagenomics, and enzyme characterization to investigate the degradation of high-molecular weight, 13C-ring-labeled synthetic lignin by microbial communities from moderately thermophilic hot spring sediment (52 °C) and a woody “hog fuel” pile (53 and 62 °C zones). 13C-Lignin degradation was monitored using IR-GCMS of 13CO2, and isotopic enrichment of DNA was measured with UHLPC-MS/MS. Assembly of 42 metagenomic libraries (72 Gb) yielded 344 contig bins, from which 125 draft genomes were produced. Fourteen genomes were significantly enriched with 13C from lignin, including genomes of Actinomycetes (Thermoleophilaceae, Solirubrobacteraceae, Rubrobacter sp.), Firmicutes (Kyrpidia sp., Alicyclobacillus sp.) and Gammaproteobacteria (Steroidobacteraceae). We employed multiple approaches to screen genomes for genes encoding putative ligninases and pathways for aromatic compound degradation. Our analysis identified several novel laccase-like multi-copper oxidase (LMCO) genes in 13C-enriched genomes. One of these LMCOs was heterologously expressed and shown to oxidize lignin model compounds and minimally transformed lignin. This study elucidated bacterial lignin depolymerization and mineralization in thermal ecosystems, establishing new possibilities for the efficient valorization of lignin at elevated temperature.

Kamera-Ethnographie ist ein filmischer Ansatz zur Gestaltung der Wahrnehmungs- und Wissensprozesse beim ethnographischen Forschen. Dabei wird im Unterschied zur Logik der Aufzeichnung angenommen, dass Forschungsgegenstände zunächst noch gar nicht sichtbar sind. Kameraführung, Schnitt und Montage tragen als experimentelle Praktiken zur Beobachtbarkeit und Sichtbarkeit epistemischer Dinge bei. Bina Elisabeth Mohns repräsentationskritische Programmschrift zeigt, wie die Methode der Kamera-Ethnographie auch nonverbale Praktiken in ihren Choreographien und bildhaften Figuren in den Blick rückt. Eine situierte Methodologie und reflexive Pragmatik leiten zum positionierten Hinschauen und Sehenlernen an und binden selbst das Publikum in eine forschende Rezeption ein.

The formation and evolution of back-arc basins is complex controlled by subduction dynamics, lithosphere delamination, magmatism, slab roll-back and extension. In such a complex geodynamic context, it is difficult to decipher the mechanisms which controls sedimentary basin subsidence history and distinguish the contribution of lithosphere tectonics from dynamic topography.Here we focus on one of the main basins of the Western Mediterranean, the Valencia Trough, which formed in the Cenozoic in relation with the slab roll-back of the Tethyan oceanic lithosphere. More specifically, we investigate the subsidence and geodynamic context related to the formation of a regionally observed unconformity, which separates Mesozoic from latest Palaeogene to Neogene sediments, and here referred to as the Miocene Unconformity.Using a dense grid of seismic reflection data, well data and 3D flexural backstripping, we show that the Miocene Unconformity subsided by more than 1.5 km from ~17 Ma to the present day at an average rate of 90 m/Myr in the SW Valencia Trough. The absence of Cenozoic extensional faults affecting the basement shown by seismic data indicates that this rapid subsidence is not caused by Cenozoic rifting. This subsidence cannot be explained by flexural loading related to the adjacent thin-skin Betic fold and thrust belt either, which only affects subsidence observed near the deformation front. Subduction dynamic subsidence generated by the positive mass anomaly of the subducting slab in the mantle is another mechanism that can control the subsidence evolution of back-arc basins. However, since the formation of the Miocene unconformity, the subduction has propagated westwards and southwards and has slowed or ceased under the Valencia Trough, which would have resulted in the progressive diminution of subduction dynamic subsidence, generating a relative uplift rather than subsidence.We propose an alternative mechanism and interpret the 1.5 km subsidence of the Miocene Unconformity as the collapse of a back-arc transient uplift event. Erosion during the uplift, resulting in the formation of the unconformity, is estimated to exceed 4 km. This transient uplift was likely caused by heating of back-arc lithosphere and asthenosphere, combined with mantle dynamic uplift, both caused by segmentation of Tethyan subduction resulting in slab tear. Rapid subsidence subsequently resulted from the removal of mantle flow dynamic support from the Tethyan subduction slab roll-back and thermal equilibration.Our observations and interpretation of rapid back-arc kilometre-scale uplift and collapse might have global applicability to explain some of the observed vertical motions and the subsidence evolution of other back-arc regions experiencing subduction segmentation and slab tear during subduction slab roll-back.

The isotopic composition of nitrous oxide (N2O) reveals valuable information on the biological production sources that contribute to N2O accumulation in the atmosphere, i.e. denitrification, nitrifier-denitrification and nitrification1. Isotopic fingerprints for each of these microbial pathways have been identified in past work, however, overlapping signatures of co-occurring N2O production processes2, and limitations in the robustness of associated fractionation factors under varying growth/environmental conditions3 still pose significant challenges.We will present data from the initial phase of our project, where we study N2O production and associated N and O isotopic fractionation by the denitrifier Pseudomonas aureofaciens, grown in the laboratory under different growth conditions and thus different reaction kinetics. N2O production was quantified on-line by Fourier-Transformation IR-spectroscopy (FTIR), and the isotopic composition of produced N2O was determined by quantum cascade-laser-absorption spectroscopy (QCLAS). The combination of N2O production and isotope data (continuously measured) allowed us to elucidate changes in N and O isotope fractionation in response to changing reaction kinetics.In a later phase of the project, we will expand our isotope-analytical capability by including also the doubly-substituted molecules of N2O, 15N15N16O (556), 14N15N18O (458) and 15N14N18O (548). More specifically, we will interrogate the symmetry of N – N bond formation, verify combinatorial effects during N2O production, and we will test whether Δ556, Δ458, and Δ548 (and the preference for 15N substitution in the central/terminal N-position) can be applied as proxies for reaction kinetics4, 5. 1 Yu, L., Harris, E., Lewicka Szczebak, D., Barthel, M., Blomberg, M.R., Harris, S.J., Johnson, M.S., Lehmann, M.F., Liisberg, J., Müller, C. and Ostrom, N.E., 2020. What can we learn from N2O isotope data?–Analytics, processes and modelling. Rapid Communications in Mass Spectrometry, 34(20), p.e8858.2 Kantnerová, K., Tuzson, B., Emmenegger, L., Bernasconi, S.M. and Mohn, J., 2019. Quantifying isotopic signatures of N2O using quantum cascade laser absorption spectroscopy. Chimia, 73(4), pp.232-232.3 Haslun, J.A., Ostrom, N.E., Hegg, E.L. and Ostrom, P.H., 2018. Estimation of isotope variation of N2O during denitrification by Pseudomonas aureofaciens and Pseudomonas chlororaphis: implications for N2O source apportionment. Biogeosciences, 15(12), pp.3873-3882.4 Yeung, L.Y., 2016. Combinatorial effects on clumped isotopes and their significance in biogeochemistry. Geochimica et Cosmochimica Acta, 172, pp.22-38.5 Kantnerová, K., Hattori, S., Toyoda, S., Yoshida, N., Emmenegger, L., Bernasconi, S.M. and Mohn, J., 2022. Clumped isotope signatures of nitrous oxide formed by bacterial denitrification. Geochimica et Cosmochimica Acta, 328, pp.120-129.

Cenozoic rifting in the South China Sea developed after a Mesozoic Andean-type orogeny (i.e., Yanshanian orogen) which led to structural, compositional, and thermal inheritance.These inherited lithospheric weaknesses can control the inception and evolution of rifting, as well as the final architecture of the rifted continental margin. In order to better understand these processes, recent studies have utilized seismic profiles, drill cores, and geochronological analysis to identify Mesozoic strata, magmatic rocks related to a former arc, and pre-Cenozoic fault systems in the region. These findings reveal that the pre-rift lithosphere was heterogeneous and that inherited structures affected the subsequent Cenozoic rift evolution.Here we use multi-stage models to investigate the impact of tectonic inheritance on the spatiotemporal evolution and final rift margin architecture in the South China Sea. We employ a numerical forward model that includes a two-way coupling strategy (Neuharth et al., 2022) linking the geodynamic code ASPECT and the landscape evolution model FastScape. We reproduce the first-order kinematic evolution of the South China Sea by imposing accordion type models of continental collision, followed by extension. We present a reference model that incorporates orogenic topography, thrust fault distribution, and the architecture of the rifted margin, while also accounting for realistic crustal thicknesses, heat flow, and lithosphere-asthenosphere boundary (LAB) properties. This model was derived by conducting a systematic evaluation of a suite of models that varied in terms of lithosphere rheology, convergence velocity, heat production, erosion rate, and random initial noise distribution.Our reference model reproduces a range of observations including continental collision, post-orogenic collapse, continental rifting and lithospheric breakup. During orogeny, the lithosphere undergoes thrust faulting, and crustal thickening, leading to the formation of inherited weakness in the crust. From orogenic collapse to continental rifting, pre-existing thrust faults serve as nucleation sites for normal faults, and their interaction with later rift-related normal faults can locally modify the regional stress field. During rifting, low-angle detachment faults which connect the reactivated thrust faults contribute to the overall deformation of the lithosphere. In this model, crustal thickening led to increasing temperature, which resulted in a more ductile lower crust with a rheological transition from brittle to ductile deformation. This thermal weakening of the lower crust allows for increased deformation and strain accommodation during lithospheric stretching. The presence of pre-existing thrust faults and a more ductile lower crust ultimately led to the formation of wide rifted margin of the South China Sea. We suggest that this finding is applicable to other post-orogenic, wide rifts worldwide, such as the Basin and Range Province, the Aegean Sea and the West Anatolian extensional system.[1] Neuharth, D., Brune, S., Wrona, T., Glerum, A., Braun, J., & Yuan, X. (2022). Evolution of rift systems and their fault networks in response to surface processes. Tectonics, 41(3), e2021TC007166.

This contribution explores the formation and evolution of hyper-extended basins controlled by low-angle normal faults active at

The Rif belt (Northern Morocco) represents the western termination of the Maghrebides system. It is subdivided into three tectono-stratigraphic domains known as: Internal domain (i.e., Alboran domain), the Maghrebian flysch domain (i.e., the sedimentary cover of the Maghrebian Tethys) and the external domain (i.e., north African passive paleo-margin and its sedimentary infill. The Rif fold-and-thrust belt derives from the deformation of the North African passive Paleo-margin and its sedimentary infill since the onset of Africa-Eurasia convergence. The compressional setting led to the progressive closure of the Maghrebian Tethys and westward translation of the Alboran Domain and its docking onto the Northwest African rifted margin during the Late Burdigalian. However, field structural survey revealed the presence of an important Paleogene unconformity in the External domain, attesting for a deformation older than the Miocene Alpine compression.Thus, to unravel the Cenozoic history of the Rif fold-and-thrust belt and its burial paths, a regional transect NE-SW-oriented crossing the Rif fold-and-thrust belt is studied. The methodological approach consists in combining organic petrography, micro-Raman spectroscopy on organic matter, clay mineralogy and 1D thermal modelling, together with field structural data.A new paleo-thermal data set of vitrinite reflectance (Ro%), Raman micro-spectroscopy and %I in I/S mixed layers has been provided. The obtained results show a thermal jump between the Miocene deposits in the Mesorif (External Domain) and their Eocene substratum. In order to fit the paleo-thermal data, the thermal modelling indicates the erosion of about 1300-1900 m of sedimentary and/or tectonic pile before the deposition of Lower Miocene siliciclastic. The obtained results have been used to highlight a disregarded tectonic event affecting the north African paleo-margin and how it is influencing the Miocene orogenic processes.

The isostatic evolution and bathymetry of rifted margins depends on thinning of continental crust, the volume of magmatic additions, lithosphere thermal perturbation during rifting and its post-rift re-equilibration, and sediment loading. Additionally, at some margins, bathymetric evolution may also be affected by basin isolation, where eustatic variations are not controlled by global sea-level changes, and mantle plume dynamic uplift and its collapse. The relative influence of these contributors to rifted margin bathymetric evolution varies from example to example.Here we investigate the parameters controlling the palaeobathymetric evolution of the Nova Scotian rifted margin during the early stages of the opening of the Central Atlantic Ocean, following Triassic rifting, salt deposition and early Jurassic continental breakup. We use a 3D flexural backstripping technique which incorporates decompaction and post-breakup reverse thermal subsidence modelling to provide palaeobathymetric predictions through the Cretaceous down to the Late Triassic base salt.Quantitative analysis of seismic reflection and gravity anomaly data together with residual depth anomaly analyses have also been used to determine variations of crustal thickness and crustal type as well as volumes of magmatic addition emplaced during rifting and continental breakup. We show the magma-rich to magma-poor transition of the Nova Scotian margin, characterized by seaward dipping reflectors (SDRs) in the SW, while in the NE mantle is possibly exhumed.Comparison of our palaeobathymetric predictions with seismic observations and palaeoenvironments deduced from biostratigraphy of drill samples are in good agreement over the continental shelf. As expected, discrepancies exist more distally related to salt withdrawal and sediment gravity-driven sliding. Palaeobathymetries predicted seaward, on the first oceanic crust, range from 2 to 2.5 km; values in the range of those observed at young oceanic ridges.The oceanic crust of the SW Nova Scotian margin shows well developed sequences of SDRs. Their morphology resembles that of inner SDRs of volcanic margins like the Norwegian and Greenland margins (North Atlantic), where drilling results indicate that they correspond to lava-flows emplaced near or above sea-level. Our predicted palaeobathymetry of top SDRs at breakup is nearly ~2km deeper than the expected near sea-level. This discrepancy suggests that the subsidence of this thick oceanic crust with SDRs requires an additional mechanism in addition to post-rift thermal subsidence.Mantle plume uplift and collapse likely occurs at volcanic margins and has a long wavelength of the order of 500 km or more. However, the subsidence discrepancy we observe has a shorter wavelength and seems focused along the nascent spreading axis. Thinning of the thick oceanic crust after SDR emplacement by oceanward lateral flow of molten and ductile lower crust is an alternative possibility and may be a common occurrence at volcanic rifted margins after continental breakup.

Methane clumped isotope thermometry relies on accurate measurements of relative abundances of the doubly-substituted isotopologues 12CH2D2 and 13CH3D. Calibration of the thermometer requires, regardless of the applied technique, i.e., laser absorption spectroscopy or high-resolution mass spectrometry, routine preparation of thermally re-equilibrated samples spanning the temperature and bulk isotopic composition (δ13C-, δD-CH4) range of the target applications.Here we present a practical method for methane isotopologue re-equilibration over activated γ-Al2O3. We demonstrate complete and reproducible re-equilibration of clumped isotope signatures with minimal alteration of the bulk isotope composition, almost complete sample recovery, and no detectable formation of decomposition products. Samples spanning a range in δD-CH4 of 100 ‰ were equilibrated between 100 °C and 500 °C and used to calibrate a high-resolution quantum cascade laser absorption spectrometer. In addition, we report on a comparison between the spectroscopic measurements carried out at Empa and an independently calibrated high-resolution mass spectrometric technique using a Thermo MAT253 Ultra at IMAU, Utrecht University.This study is supported by the European Commission under the Horizon 2020 – Research and Innovation Framework Programme, H2020-INFRAIA-2020-1 (grant no. 101008004) and the Swiss National Science Foundation project no. 200021_200977.

The wide rifting mode that preceded the opening of the South China Sea in the Cenozoic generated a complex network of sedimentary basins, whose structure is currently being investigated. Until now, most studies focused on the Pearl River Mouth segment. Comparatively, towards Taiwan, the crustal structure of the north-easternmost part of the South China Sea margin (Tainan-Taixinan Basin sensu lato) is less explored.To investigate the crustal structure of this segment, an extensive open access data set was used, including (a) 07 offshore well logs with biostratigraphic information, (b) over 15,000-line km of two-dimensional reflection seismic (c) over 4,100-line km of refraction seismic, (d) satellite free-air gravity anomaly data, and (e) bathymetry (GEBCO 15 seconds grid in meters). We interpreted seismic data together with the results of a gravity inversion scheme that provides three-dimensional variations of Moho depth and crustal thickness. The joint inversion of interpreted seismic and gravity-inverted Moho enabled the determination of crustal basement density variations along a set of 2D profiles.This integrated approach enables us to distinguish at least five crustal domains from the continental shelf towards the ocean (i.e., north to south) showing contrasted stratigraphic and structural style, crustal thicknesses, and basement densities. (a) The proximal margin is characterized by a continental basement between 19 and 37 km thick, likely including thick Mesozoic to Paleozoic sediments and numerous intrusive rocks. (b) The necking zone is associated with the deepening of the top basement and increasing crustal thinning. This domain widens toward the northeast and is controlled by counter-regional faults that created half grabens filled by polyphasic syn-rift sediments. (c) To the south, the hyper-thinned crust (2900 kg/m-3), the scarceness or absence of faulting, and the onlap of Miocene sediments. The transition towards the unambiguous oceanic domain is characterized by an array of outer highs of likely dominantly magmatic origin. (e) Unambiguous oceanic crust is characterized by chaotic high-amplitude crust with an average thickness of ~6 km, passively draped by post-Oligocene sediments.This segment of the South China Sea margin is characterized by the presence of a failed rift axis, underlain by hyper-thinned crust. The age of rifting is not directly constrained, but this basin likely preserves the oldest rift phase preceding the opening of the South China Sea. Further south, the peculiar high-average density crustal domain appears most likely of magmatic origin, where Mesozoic to Cenozoic basalts have been dredged.These new results on the crustal structure of the north-easternmost part of the South China Sea margin point toward a polyphase magmatic activity and more complex tectonic history than previously assumed.

Anammox plays a pivotal role in both natural and engineered systems as a process that simultaneously converts fixed nitrogen to N2 and regenerates NO3–. In aquatic and terrestrial ecosystems, isotopic measurements, especially of the NO3– pool, provide an essential constraint on the processes that regulate the supply and elimination of fixed nitrogen, but the isotope effects of anammox remain poorly constrained.We present measurements of the δ15N and δ18O of NO3–, NO2–, and NH4+ as processed by anammox in a mixed microbial community enriched for N removal from wastewater. We find that oxygen isotope effects expressed in NO2– include a substantial contribution from equilibration reactions with water superimposed on kinetic isotope effects. Equilibrium between water and NO2– during processing by anammoxis greatly accelerated above rates observed under abiotic conditions even during growth phases when NO2– is rapidly being consumed. In turn, δ18O of NO3– nearly completely reflects the incorporation of O atoms derived from water with little additional isotopic fractionation. The δ15N values of NO3– and NO2– also show evidence for an equilibrium isotope exchange reaction between these molecules, which raises the possibility that nitrite oxidation is partially reversible, while introducing a high degree of variability into the δ15N of NO3– generated by anammox. Finally, variation observed in the δ15N of NH4+ consumed by anammox can be connected to physiological limitations within the anammox cell.Despite this complexity, we were able to use NO2– and NO3– isotope measurements to diagnose changes in the activity of anammox and related processes within the wastewater treatment system during a low-temperature perturbation experiment. These results provide new constraints for interpreting the variability in δ15N and δ18O of NO3–in natural systems, with implications for estimating relative rates of fixed N turnover processes.

The Northeast Greenland shelf is a broad Arctic shelf located between Greenland and Fram Strait. It is the principal gateway for sea ice export and sea ice-associated freshwater from the Arctic Ocean. Sea ice thickness has decreased by 15% per decade since the early 1990s and meteoric freshwater discharge has increased. The consequence of changing sea-ice and freshwater conditions in the region on ocean dynamics and the biological system remains unknown. Determining the source(s) of freshwater is important to be able to understand how the area will react to future upstream change. Here we present a synoptic survey of the Northeast Greenland shelf and slope with observations of hydrography, the nutrients nitrate, phosphate and silicate, and conservative tracers δ18O, δ2H and total alkalinity during late summer 2017. We compare these to previously published values, including those which identify Pacific and Atlantic water, the Siberian shelf seas, and the 6 largest Arctic rivers. We show that a major source of freshwater on the Northeast Greenland shelf during late summer 2017 is the Laptev Sea and find no conclusive evidence of Pacific Water. Our observations provide a direct link between Northeast Greenland hydrology and processes occurring on Eurasian shelves.

Natural and engineered nitrogen (N) removal processes in aqueous systems represent important sources of nitrogenous gas emissions, including the potent greenhouse gas nitrous dioxide (N2O). The relevance of microbial and abiotic formation pathways can be assessed using 15N tracing techniques. While 15N-N2O analysis using optical analyzers is straightforward, quantification of 15N fractions in inorganic N compounds, ammonium (NH4+), nitrite (NO2-), and nitrate (NO3-), is typically time-consuming and labor-intensive.In this study, we developed an automated sample-preparation unit coupled to a membrane-inlet quadrupole mass spectrometer (3n-ASSP-MIMS) for the online quasi-simultaneous analysis of 15N fractions in NH4+, NO2-, and NO3-. The technique was designed and validated for applications at moderate (100 - 200 μmol L-1) to high (2 – 3 mmol L-1) N, as found in sewer systems, wastewater in treatment plants, or eutrophic surface waters, and 15N spiking (f15) between 1 and 33%.The potential of 3n-ASSP-MIMS was demonstrated in a feasibility study, where the technique, in conjunction with 15N-N2O analyses by FTIR spectroscopy, was applied to pinpoint nitrifier denitrification as the primary N2O formation pathway during partial NH4+ oxidation to NO2- in a lab-scale sequencing batch reactor.

N2O isotopic composition, i.e., δ15N-N2O, δ18O-N2O and especially site preference (SP; difference of substitution frequencies at terminal or central position in N-N-O molecule) has been shown to provide information on N2O source processes, and allows for source partitioning of N2O emissions to nitrification and denitrification. The advent of laser spectrometers more than a decade ago has spawned first datasets of N2O isotopic composition in daily resolution, but they have remained scarce. This is because until recently, the precision of commercially available spectrometers did not allow direct determination of N2O isotopic composition without technically challenging liquid nitrogen free cryogenic preconcentration of N2O. The specifications of the latest commercially available spectrometers promised preconcentration free in-situ determination of N2O isotopic composition, but a recent instrument intercomparison showed that for most of the analyzers, specific correction functions are still necessary. While some available instruments were thoroughly characterized with regard to short term precision, repeatability, drift, amount effects, matrix effects and spectral interferences, instrument performance during field deployment and on the time scale of long measurement campaigns has not been analysed so far.Here we present a setup and results of an automated chamber system in conjunction with a laser spectrometer that was installed in the field and in use for a period of approx. two years. Initially, amount dependence was in the range of 4 to 2 ‰ ppm N2O-1 for the various isotopic species, but instrument optimizations reduced this dependence to less than 1 ‰ ppm N2O-1. CH4 dependence was constant through the whole period and in the range of 1 to 2 ‰ ppm CH4-1, with affecting only δ15Nα and δ18O. In contrast, CO2 dependence was variable and in the same range as N2O amount dependence. The uncertainty budget was dominated by instrument noise, calibration and N2O amount dependence, indicating that improvements of instrument precision and availability of more suitable reference materials have a high potential to further decrease uncertainty of measurements. Analysis of the effect of uncertainty on the error of determined soil air N2O isotopic composition based on Keeling plots resulted in an error of 2 ‰ and 1 ‰ at N2O concentration increases of 70 and 140 ppb, respectively. Consequently, source partitioning based on SP will be associated with an error of 17 and less than 12% at the moment. Compared to growing-season emissions, SP and δ18O-N2O during freeze-thaw cycles were distinctly different. SP was ~0, indicating that N2O reduction to N2 was negligible during freeze-thaw events.

Chemical imaging via advanced optical microscopy technologies has revealed remarkable details of biomolecules in living specimens. However, the ways to control chemical processes in biological samples remain preliminary. The lack of appropriate methods to spatially regulate chemical reactions in live cells in real-time prevents investigation of site-specific molecular behaviors and biological functions. Chemical- and site-specific control of biomolecules requires the detection of chemicals with high specificity and spatially precise modulation of chemical reactions. Laser-scanning optical microscopes offer great platforms for high-speed chemical detection. A closed-loop feedback control system, when paired with a laser scanning microscope, allows real-time precision opto-control (RPOC) of chemical processes for dynamic molecular targets in live cells. In this perspective, we briefly review recent advancements in chemical imaging based on laser scanning microscopy, summarize methods developed for precise optical manipulation, and highlight a recently developed RPOC technology. Furthermore, we discuss future directions of precision opto-control of biomolecules.

Objectives We aimed to characterize the effects of COVID-19 Pandemic on 2-h glucose values after an OGTT postulating a correlation between 2-h glucose spectrum and the decline of β-cell function. Particularly, we tried to evaluate the effects on the risk of showing 2-h glucose values in the highest range of normal values in obese children and adolescent during COVID-19 Pandemic compared to those evaluated during the 13 years before. Subjects/Methods Data from 532 obese and overweight children and adolescents (before COVID-19 Pandemic, 209M/262F, 2008–2019; during COVID-19 Pandemic, 40M/21F, 2020–2021) who had undergone a complete evaluation and had performed an OGTT after their first visit were analyzed. The two groups were further divided into three sub-groups based on the 2-h glucose values, group 1 (Results A significant difference (P = 0.01) in terms of distribution of the prevalence of 2-h glucose values was documented between the group before COVID-19 (35.6%, 45.9% and 18.5%) and the group during COVID-19 Pandemic period (31.1%, 31.1% and 37.8%). A roughly doble higher prevalence of subjects with pre-IGT was documented in the COVID-19 group. In addition, group 3 of COVID-19 time showed significantly higher values for waist circumference (WC), Waist/Height ratio (WtHR), fasting glucose, HOMA-IR, and AUC Insulin, compared to the group 3 of the period before COVID-19 Pandemic (all P Conclusions During COVID-19 time a higher percentage of children are in the highest range of normal 2-h glucose values which is known to be associated with a significant impairment of β-cell function relative to insulin sensitivity and at higher risk of developing IGT.