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Isotopic labeling is an attractive modality that has been widely used in many aspects of chemistry, the life sciences, and medical research; especially deuterated drugs and radioactive molecules have been used in the diagnosis and treatment of cancer and neurodegenerative diseases. The widespread application and rapid development of isotopically labeled molecules has led to an increased demand for new isotopic labeling chemical methods to synthesize highly specific molecules bearing defined nuclides. Multicomponent reactions (MCRs) are modular build-up approaches for the rapid generation of complex molecules often containing biologically relevant scaffold structures. There is great potential to use MCRs to construct isotopically labeled molecules because assembly speed and reaction diversity are key advantages of MCR. In this review, we provide an overview of the recent literature on this topic that can provide insight into the application of MCRs in the field of isotopic labeling. [ABSTRACT FROM AUTHOR]

The different topics and synthetic approaches in an isotope chemistry laboratory of a pharma company are described. Besides the challenges in the synthesis of long-lived isotopes such as3 H or14 C, short-lived isotopes such as68 Ga and stable isotopes such as15 N,13 C or2 H approaches for the isotopic labeling are also demonstrated. Furthermore, method development with emphasis on collaborations with academic groups to tackle the future challenges are discussed. 1 Introduction 2 Isotopic Labeling with Hydrogen Isotopes Deuterium (2 H, D) and Tritium (3 H, T) 2.1 Deuterium Labeling for MS Standards 2.1.1 Labeled Nitrosamines – The Hunt to Quantify Hazardous Impurities 2.1.2 Deuterated Drugs, an Approach To Improve Existing Drugs or To Find Opportunities in Drug Discovery 2.2 Tritium-Labeling Methods – The Fast Approach to Radioactively Labeled Compounds 2.2.1 Hydrogen Isotope Exchange by Iridium Catalysis 2.2.2 Ruthenium-Catalyzed HIE 2.2.3 Nanoparticles as Catalysts in HIE 2.2.4 Photoredox-Catalyzed HIE 2.2.5 HIE via Classical Radical Mechanism 2.2.6 Beyond HIE – Halogen–Tritium Exchange 3 Challenges in14 C-Synthesis Projects 4 Short-Lived Isotopes – The Need for Speed 5 Beyond Isotope Science – Late-Stage Functionalization 5.1 Examples of Late-Stage Functionalization for Peptides 5.2 Examples of Catalyst-Controlled Late-Stage Functionalization 6 Conclusion [ABSTRACT FROM AUTHOR]

Interpreting the paleomagnetic records of altered rocks, especially those from Earth's earliest history, is complicated by metamorphic overprints and recrystallization of ferromagnetic minerals. However, these records may be as valuable as a primary signal if the timing and mechanism of alteration‐related remagnetizations can be ascertained. We illustrate the success of this approach in the case of seafloor hydrothermal alteration by integrating simple rock magnetic and magnetic microscopy data with petrography, hyperspectral imagery, aeromagnetic surveys, field mapping, and geochronology of Paleoarchean basalts from North Pole Dome located in the East Pilbara Craton, Western Australia. We identify 12 hydrothermal episodes during the deposition of the stratigraphy between ∼3490 and 3350 Ma. These episodes produced stratabound zones of hydrothermal alteration with predictable facies successions of mineral assemblages reflecting sub‐seafloor gradients in fluid temperature, pH, composition, and water/rock ratios. Rock magnetic data and magnetic microscopy pinpoint the secondary ferromagnetic minerals within each alteration assemblage, revealing a specific single‐domain magnetite population within leucoxenes (titanite and anatase after primary titanomagnetites) that always accompanies low‐water/rock alteration in fluids buffered to pH equilibrium with the host basalts. Highly uniform magnetic properties indicate that once formed, these magnetites remain unchanged upon further exposure to rock buffered fluids, stabilizing them against later alteration events and making them durable paleofield recorders. The altered basalts hosting this magnetite have unique and consistent appearances, mineralogy, IR absorption features, aeromagnetic signatures, and magnetic properties across all hydrothermal systems studied here, highlighting how integrating these data sets can identify and interpret this alteration style in future paleomagnetic investigations. Plain Language Summary: Paleomagnetists interpret the magnetic signals preserved in rocks to understand plate tectonics and the Earth's magnetic field in the deep past. However, rocks can get altered via heat, pressure, or chemical reactions, which also alter these magnetic signals. The aim of this study is to demonstrate that one type of alteration—chemical alteration of rocks as they marinate in circulating hot water within seafloor hydrothermal systems—modifies the magnetic signals of rocks in order to use them for future paleomagnetic studies. Using airborne infrared imaging, magnetic field mapping, field observations, and radiometric dating, we demonstrate that an area of Western Australia called North Pole Dome experienced a dozen seafloor hydrothermal alteration events over 3 billion years ago. We then use magnetic measurements and mineralogical observations to document how these hydrothermal systems altered the magnetic signals in their host rocks. These analyses reveal a recognizable population of altered rocks that can preserve paleomagnetic signals related to hydrothermal alteration. This is because the alteration results in the growth of very fine‐grained magnetite with all the necessary characteristics to reliably and durably hold onto magnetic signals over geologic time. Key Points: Field mapping, remote sensing, and petrographic data identify 12 seafloor hydrothermal episodes in an Archean volcanic successionMagnetic and mineralogical characteristics of the basalts predictably co‐vary with alteration facies across all hydrothermal systemsWe establish a geologic, chronological, and petrographic framework for identifying seafloor hydrothermal remagnetization in basalts [ABSTRACT FROM AUTHOR]

Fluid infiltration into (meta-)carbonate rocks is an important petrologic process that induces metamorphic decarbonation and potential mineralization of metals or nonmetals. The determination of the infiltration time and the compositional features of reactive fluids is essential to understand the mechanism and process of fluid–rock interactions. Zirconolite (ideal formula: CaZrTi 2 O 7) is an important U-bearing accessory mineral that can develop in metasomatized metacarbonate rocks. In this study, we investigate the occurrence, texture, composition, and chronology of various types of zirconolite from fluid-infiltrated reaction zones in dolomite marbles from the Mogok metamorphic belt, Myanmar. Three types of zirconolite are recognized: (1) the first type (Zrl-I) coexists with metasomatic silicate and oxide minerals (forsterite, spinel, phlogopite) and has a homogeneous composition with high contents of UO 2 (21.37 wt %–22.82 wt %) and ThO 2 (0.84 wt %–1.99 wt %). (2) The second type (Zrl-II) has textural characteristics similar to those of Zrl-I. However, Zrl-II shows a core–rim zonation with a slightly higher UO 2 content in the rims (average of 23.5 ± 0.4 wt % (n=8)) than the cores (average of 22.1 ± 0.3 wt % (n=8)). (3) The third type (Zrl-III) typically occurs as coronas around baddeleyite and coexists with polycrystalline quartz. Zrl-III has obviously lower contents of UO 2 (0.88 wt %–5.3 wt %) than those of Zrl-I and Zrl-II. All types of zirconolite have relatively low rare earth element (REE) contents (< 480 µ g g -1 for Σ REE). Microtextures and compositions of the three zirconolite types, in combination with in situ zirconolite U–Pb dating using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), reveal episodic fluid infiltration and element mobilization in the dolomite marbles. The first-stage infiltration occurred at ∼ 35 Ma, leading to the formation of Mg-rich silicates and oxides and accessory minerals (Zrl-I, baddeleyite, and geikielite). The reactive fluid was characterized by high contents of Zr, Ti, U, and Th. After that, some Zrl-I grains underwent a local fluid-assisted dissolution–precipitation process, which produced a core–rim zonation (i.e., the Zrl-II type). The final stage of fluid infiltration, recorded by the growth of Zrl-III after baddeleyite, took place at ∼ 19 Ma. The infiltrating fluid of this stage had relatively lower U contents and higher SiO 2 activities than the first-stage infiltrating fluid. This study illustrates that zirconolite is a powerful mineral that can record repeated episodes (ranging from 35 to 19 Ma) of fluid influx, metasomatic reactions, and Zr–Ti–U mineralization in (meta-)carbonates. This mineral not only provides key information about the timing of fluid flow but also documents the chemical variation in reactive fluids. Thus, zirconolite is expected to play a more important role in characterizing the fluid–carbonate interaction, orogenic CO 2 release, and the transfer and deposition of rare metals. [ABSTRACT FROM AUTHOR]

Peperites are volcanosedimentary materials generated by the mingling of magma and unconsolidated wet sediments. They have unique insights into submarine volcanisms and the tectonic environments where they form. For the 1st time, the authors identified two types of peperites (blocky and fluidal) hosted by micritic limestone rocks in the Walash Volcanosedimentary Group of the Mawat area, Kurdistan Region-Iraq. They are designated as peperitic facies one and two (PF1 and PF2) and consist of black basaltic rocks mixed with chocolate-brown micritic limestone rocks. Their abundance demonstrates the contemporaneity of deep marine sediment deposition and submarine volcanism during Walash's nascent arc. Despite hydrothermal alteration, the basaltic rocks retained their magmatic textures. Basaltic rocks comprise mainly albite, anorthite, diopside, hematite, and alkali-feldspar. Calcite dominates micritic limestone rocks, while quartz is minor. Based on geochemical data, igneous sections are basaltic rocks with tholeiitic series that are strongly enriched in Light Rare Earth Elements with low concentration ratios of (La/Yb) and (Sr/Y), indicating geochemical affinity to normal island arc basalt with a primitive arc signature. Furthermore, their formation is thought to be caused by partial melting of subducted slabs deep within 30 km and the associated derived fluids above the subducted slab. Thirteen species of planktonic foraminifera (Morozovella) are identified through paleontological research and biostratigraphy. Using these various tools lead the authors to illustrate the tectonic setting of the formation of peperitic rocks in arc fronts of the subducted Walash arc during the Middle to Late Paleocene (60 Ma). [ABSTRACT FROM AUTHOR]

The Tethyan evolution depicts the continuous process of landmasses separating from the Gondwana continent in the south, drifting northwards, and subsequently colliding with the continents in the north over the past 500 million years. In this process, the Tethyan oceans that formed between the landmass and the southern or northern continents underwent growth, evolution, and eventual closure with the early Cenozoic India-Eurasia collision. However, the Tethyan lithosphere did not disappear but rather continued to evolve after entering into the deep Earth. The current position, morphology, and volume of the subducted Tethyan oceanic slabs in the deep mantle record the latest moment of this continuous evolution, providing critical constraints for Tethyan studies. This paper summarizes and analyzes the results of global-scale whole-mantle seismic tomography in the past nearly two decades, revealing a northwest-southeast seismically high-velocity anomaly, which is linearly distributed at depths of 1000–2000 km beneath the Tethyan realm and referred to as the Tethyan anomaly. By searching for an optimal linear combination of previous global seismic tomographic models to best match the known subducted slabs in the upper mantle, we observe that the Tethyan anomaly extends approximately 8700 km in length and 2600 km in width, exhibiting a parallel structure with northern and southern branches. Combining geological records of oceanic subduction initiation and previous geodynamic studies, this study suggests that the main body of the Tethyan anomaly represents the remnants of the subducted Neo-Tethyan oceanic slabs, which subducted from the Late Jurassic to the early Cenozoic. The northern branch consists of subducted slabs from the Neo-Tethys beneath the southern margin of Eurasia, while the southern branch likely reflects the intra-oceanic subducted slabs of Neo-Tethys during the Cretaceous. The western portion of the Tethyan anomaly may reflect remnants of Paleo-Tethys, while the eastern portion, towards India and the Bay of Bengal, shows signs of subduction towards the core-mantle boundary. Finally, this study discusses the future prospects of whole-mantle seismic tomographic studies focusing on the Tethyan realm. [ABSTRACT FROM AUTHOR]

Mineral Resource downgrades can be prevented by integrating better structural geological interpretations into project evaluations. Geological modelling for Mineral Resource estimation is presented as a systematic process of structural geological analysis at the deposit-scale using drill-sampled grade data. The initial step in this process is to use Maximum Intensity Projection (MIP) rendering to interpret axial symmetry and its orientation from the grade interval mid-points at the deposit-scale, thus reducing the modelling process's degrees of freedom to only three—estimating the prolateness of the grade or lithological distribution. This approach contrasts with the brute-force methods for assessing modelling uncertainty because the axial direction is fixed to the down-plunge orientation, thus eliminating from the outset, structurally implausible geometric configurations and unrealistic geological scenarios common in brute-force methods. Adopting this new approach of creating geological models means moving away from conventional mining industry methods that prioritise operational considerations in constructing resource estimates but fail to explain the geometric complexities of mineral deposits. We use experiments and a practical case study of a historical gold mine in Western Australia to highlight the significance of analysing the structural control of a gold deposit at the deposit-scale using raw grade data. Our research is based on anecdotal evidence suggesting that erroneous geological modelling leads to unforeseen Mineral Resource downgrades. However, we cannot confirm this hypothesis because there have been few, if any, independent public inquiries into Mineral Resource downgrades. To establish the underlying reasons for significant resource downgrades with certainty, impartial investigations (modelled on accident investigations in the aviation industry) are imperative. There is a general lack of incorporating structural geological knowledge in creating resource models, which can lead to poor outcomes such as Mineral Resource downgrades. Structural geological analysis of drill-sampled raw grade data allows the structural controls on a deposit to be better understood. We offer a simple workflow for understanding and modelling these patterns. [ABSTRACT FROM AUTHOR]

Toxicogenomics is a critical area of inquiry for hazard identification and to identify both mechanisms of action and potential markers of exposure to toxic compounds. However, data generated by these experiments are highly dimensional and present challenges to standard statistical approaches, requiring strict correction for multiple comparisons. This stringency often fails to detect meaningful changes to low expression genes and/or eliminate genes with small but consistent changes particularly in tissues where slight changes in expression can have important functional differences, such as brain. Machine learning offers an alternative analytical approach for "omics" data that effectively sidesteps the challenges of analyzing highly dimensional data. Using 3 rat RNA transcriptome sets, we utilized an ensemble machine learning approach to predict developmental exposure to a mixture of organophosphate esters (OPEs) in brain (newborn cortex and day 10 hippocampus) and late gestation placenta of male and female rats, and identified genes that informed predictor performance. OPE exposure had sex specific effects on hippocampal transcriptome, and significantly impacted genes associated with mitochondrial transcriptional regulation and cation transport in females, including voltage-gated potassium and calcium channels and subunits. To establish if this holds for other tissues, RNAseq data from cortex and placenta, both previously published and analyzed via a more traditional pipeline, were reanalyzed with the ensemble machine learning methodology. Significant enrichment for pathways of oxidative phosphorylation and electron transport chain was found, suggesting a transcriptomic signature of OPE exposure impacting mitochondrial metabolism across tissue types and developmental epoch. Here we show how machine learning can complement more traditional analytical approaches to identify vulnerable "signature" pathways disrupted by chemical exposures and biomarkers of exposure. [ABSTRACT FROM AUTHOR]

Visible-Light-Responsive Nano CuO/ZnO Photocatalyst for Chan-Lam Coupling Reaction and Aerobic C(sp3)-H Bond Oxidation Semiconductor, Chan-Lam reaction, heterogeneous photocatalyst, C(sp 3)-H bond oxidation, gram-scale synthesis Keywords: semiconductor; heterogeneous photocatalyst; Chan-Lam reaction; C(sp 3)-H bond oxidation; gram-scale synthesis EN semiconductor heterogeneous photocatalyst Chan-Lam reaction C(sp 3)-H bond oxidation gram-scale synthesis 2495 2502 8 07/31/23 20230817 NES 230817 Graph The emergence of photocatalysts can be described as one of the most important developments in the chemistry world. In summary, we have reported a convenient and practical photochemical method for the Chan-Lam coupling and C(sp SP 3 sp )-H bond oxidation reactions using nano CuO/ZnO as a sustainable and cost-effective photocatalyst. [Extracted from the article]

The Dunnage Zone of the Newfoundland Appalachians hosts diverse Cambrian–Ordovician volcanogenic massive sulfide (VMS) deposits. The peri-Laurentian Notre Dame Subzone contains Cu–Zn–Au mafic and bimodal mafic deposits in ∼501–485 Ma ophiolitic rocks and Zn–Pb–Cu–(Au–Ag) deposits in ∼471–465 Ma bimodal rifted continental arc sequences (e.g., Buchans). The peri-Gondwanan rocks of the Exploits Subzone host Zn–Pb–Cu–(Au–Ag) bimodal felsic, felsic siliciclastic, and Zn–Ag–Au hybrid bimodal felsic deposits in the ∼513–486 Ma Victoria Lake supergroup; Cu–Zn bimodal felsic to bimodal mafic deposits of the ∼486 Ma Wild Bight Group; and Cu–(Au) mafic siliciclastic deposits of the ∼466 Ma Great Burnt Lake/South Pond belt. Regardless of age or stratigraphic hosts, all VMS deposits are associated with specific magmatic assemblages and extensional tectonism (i.e., rifting). Gold-enriched deposits of the Rambler-Ming district are associated with felsic rocks that formed via slab melting and subsequent melt-mantle wedge interaction, which likely enhanced precious metal enrichment in these deposits. Whereas many deposits exhaled on the seafloor, some deposits formed via subseafloor replacement of host units or as re-sedimented sulfides generated in sediment-gravity flows. Metals in the deposits were derived from leaching of underlying footwall rocks; however, Au–Ag- and epithermal suite element-enriched deposits show evidence for metal contributions from magmatic hydrothermal fluids. Sulfur in deposits was derived predominantly from leaching of H2S from underlying footwall rocks and from thermochemical sulfate reduction of seawater sulfate, with lesser input from bacteria-derived H2S and magmatic-hydrothermal-derived H2S. Despite recent research advances and historic mining, numerous questions remain unresolved and provide opportunities for future study. [ABSTRACT FROM AUTHOR]

As a promising new micro-physiological system, organ-on-a-chip has been widely utilized for in vitro pharmaceutical study and tissues engineering based on the three-dimensional constructions of tissues/organs and delicate replication of in vivo-like microenvironment. To better observe the biological processes, a variety of sensors have been integrated to realize in-situ, real-time, and sensitive monitoring of critical signals for organs development and disease modeling. Herein, we discuss the recent research advances made with respect to sensors-integrated organ-on-a-chip in this overall review. Firstly, we briefly explore the underlying fabrication procedures of sensors within microfluidic platforms and several classifications of sensory principles. Then, emphasis is put on the highlighted applications of different types of organ-on-a-chip incorporated with various sensors. Last but not least, perspective on the remaining challenges and future development of sensors-integrated organ-on-a-chip are presented. [ABSTRACT FROM AUTHOR]

Organophosphate flame retardants (OPFRs) have become the predominant substitution for legacy brominated flame retardants but there is concern about their potential developmental neurotoxicity (DNT). OPFRs readily dissociate from the fireproofed substrate to the environment, and they (or their metabolites) have been detected in diverse matrices including air, water, soil, and biota, including human urine and breastmilk. Given this ubiquitous contamination, it becomes increasingly important to understand the potential effects of OPFRs on the developing nervous system. We have previously shown that maternal exposure to OPFRs results in neuroendocrine disruption, alterations to developmental metabolism of serotonin (5-HT) and axonal extension in male fetal rats, and potentiates adult anxiety-like behaviors. The development of the serotonin and dopamine systems occur in parallel and interact, therefore, we first sought to enhance our prior 5-HT work by first examining the ascending 5-HT system on embryonic day 14 using whole mount clearing of fetal heads and 3-dimensional (3D) brain imaging. We also investigated the effects of maternal OPFR exposure on the development of the mesocortical dopamine system in the same animals through 2-dimensional and 3D analysis following immunohistochemistry for tyrosine hydroxylase (TH). Maternal OPFR exposure induced morphological changes to the putative ventral tegmental area and substantia nigra in both sexes and reduced the overall volume of this structure in males, whereas 5-HT nuclei were unchanged. Additionally, dopaminergic axogenesis was disrupted in OPFR exposed animals, as the dorsoventral spread of ventral telencephalic TH afferents were greater at embryonic day 14, while sparing 5-HT fibers. These results indicate maternal exposure to OPFRs alters the development trajectory of the embryonic dopaminergic system and adds to growing evidence of OPFR DNT. [ABSTRACT FROM AUTHOR]

Unpredictable variation in quality, including fresh pork water-holding capacity, remains challenging to pork processors and customers. Defining the diverse factors that influence fresh pork water-holding capacity is necessary to make progress in refining pork quality prediction methods. The objective was to utilize liquid chromatography and mass spectrometry coupled with tandem mass tag (TMT) multiplexing to evaluate the sarcoplasmic proteome of aged pork loins classified by purge loss. Fresh commercial pork loins were collected, aged 12 or 14 d postmortem, and pork quality and sensory attributes were evaluated. Chops were classified into Low (N = 27, average purge = 0.33%), Intermediate (N = 27, average purge = 0.72%), or High (N = 27, average purge = 1.19%) chop purge groups. Proteins soluble in a low-ionic strength buffer were extracted, digested with trypsin, labeled with 11-plex isobaric TMT reagents, and detected using a Q-Exactive Mass Spectrometer. Between the Low and High purge groups, 40 proteins were differentially (P < 0.05) abundant. The Low purge group had a greater abundance of proteins classified as structural and contractile, sarcoplasmic reticulum and calcium regulating, chaperone, and citric acid cycle enzymes than the High purge group. The presence of myofibrillar proteins in the aged sarcoplasmic proteome is likely due to postmortem degradation. These observations support our hypothesis that pork chops with low purge have a greater abundance of structural proteins in the soluble protein fraction. Together, these and other proteins in the aged sarcoplasmic proteome may be biomarkers of pork water-holding capacity. Additional research should establish the utility of these proteins as biomarkers early postmortem and over subsequent aging periods. [ABSTRACT FROM AUTHOR]

Understanding of secular evolution of the Earth system is based largely on the rock and mineral archive preserved in the continental lithosphere. Based on the frequency and range of accessible data preserved in this record, we divide the secular evolution into seven phases: (a) "Proto‐Earth" (ca. 4.57–4.45 Ga); (b) "Primordial Earth" (ca. 4.45–3.80 Ga); (c) "Primitive Earth" (ca. 3.8–3.2 Ga); (d) "Juvenile Earth" (ca. 3.2–2.5 Ga); (e) "Youthful Earth" (ca. 2.5–1.8 Ga); (f) "Middle Earth" (ca. 1.8–0.8 Ga); and (g) "Contemporary Earth" (since ca. 0.8 Ga). Integrating this record with knowledge of secular cooling of the mantle and lithospheric rheology constrains the changes in the tectonic modes that operated through Earth history. Initial accretion and the Moon forming impact during the Proto‐Earth phase likely resulted in a magma ocean. The solidification of this magma ocean produced the Primordial Earth lithosphere, which preserves evidence for intra‐lithospheric reworking of a rigid lid, but which also likely experienced partial recycling through mantle overturn and meteorite impacts. Evidence for craton formation and stabilization from ca. 3.8 to 2.5 Ga, during the Primitive and Juvenile Earth phases, likely reflects some degree of coupling between the convecting mantle and a lithosphere initially weak enough to favor an internally deformable, squishy‐lid behavior, which led to a transition to more rigid, plate like, behavior by the end of the early Earth phases. The Youthful to Contemporary phases of Earth, all occurred within a plate tectonic framework with changes between phases linked to lithospheric behavior and the supercontinent cycle. Plain Language Summary: The record of Earth evolution is preserved in the continental rock archive, but is incomplete and our knowledge of it decreases with increasing age and depth of preservation. Based on secular cooling of the mantle and associated changing lithospheric properties, we recognize three dominant tectonic modes that have operated on Earth; stagnant lid, squishy lid, and plate tectonics. After solidification of the Earth's initial magma ocean (>4.45 Ga), the lithosphere was likely dominated by mafic crust that existed until ca. 3.8 Ga. The tectonic mode that operated at this time involved either no lithosphere‐mantle coupling (cf., stagnant lid), or coupling between non‐rigid lithosphere and convecting mantle (cf., squishy lid). The latter mode likely operated through most of the Archean (ca. 3.8–2.5 Ga), and was associated with the formation of the stable interior of continents, called cratons. The stabilization of these cratons in the latter half of the Archean (ca. 3.2–2.5 Ga) is associated with the development of rigid lithosphere and the transition to a plate tectonic mode that continues to the present day. Further changes, likely in response to the supercontinent cycle, lead to subdivisions of the Earth system between ca. 1.8 and 0.8 Ga. Key Points: Long‐term record of Earth evolution preserved in continental lithosphereThree main tectonic modes operated through Earth history: stagnant lid, squishy lid and rigid, active lid (plate tectonics)Stabilization of cratons at end of Archean marks transition to plate tectonics with supercontinent cycle controlling subsequent changes [ABSTRACT FROM AUTHOR]

The spatial distribution of the b‐value has been determined using a homogeneous earthquake catalogue from 1964 to 2018 to examine the characteristics of structural heterogeneities and their bearing on the style of faulting in the Indo‐Burma region of Northeastern India. The study region is associated with an uneven distribution of structural heterogeneities and demonstrates the mixed type of faulting, nature where the majority of earthquakes resulted mainly by thrust and strike‐slip fault. Our critical analysis demonstrates that the existence of two prominent zones is associated with high b‐values and low b‐values where the mixed type of faulting resulted in the genesis of seismicity in the study area. The high b‐values in the study area contain a large number of smaller earthquakes whilst the low b‐values comprise a smaller number of larger earthquakes distributed along with the Naga‐Disang Thrust, Kabaw Fault, and Sagaing fault systems. A close comparison between b‐values and different faulting styles reveals that the area containing a low b‐value suggests stronger seismogenic zones, where an accumulation of strain energy leads to the genesis of seismicity by thrust faulting with slight slip component whilst Indo‐Burma Ranges regions connected with b‐values (0.5–0.9) demonstrate strike‐slip to the normal mode of faulting, indicating relatively weak seismogenic zones where tensional forces are prevalent. The depth sections illustrate that lower b‐values for the upper part of the subducting slab correspond to more stress generated by tectonics compared to that of the lower part, and interestingly the deeper part of the subducting Indian slab is coupled with conspicuously very high‐b values, suggesting the weakening of the Indian subducting slab through dehydration. [ABSTRACT FROM AUTHOR]

The Fraser Zone of the Albany-Fraser Orogen of Western Australia contains an extensive suite of mafic and mafic–ultramafic intrusions. This includes the Nova-Bollinger intrusions (ca 1300 Ma), which host economic Ni-sulfide mineralisation, a prime example of magmatic sulfide liquids emplaced into the deep crust under ambient granulite facies conditions. Sulfur, Sr and Sm–Nd isotopes, and trace elements have been used to evaluate the role of crustal contamination of the parental magmas to Nova-Bollinger and other sulfide-bearing mafic–ultramafic bodies within the Fraser gabbro suite. All ore types have δ34S values between +1.6 and +8.0‰ VCDT with a positively skewed distribution and a median value of +2.3‰ VCDT, anomalous relative to uncontaminated mantle values near 0‰ VCDT. No significant Δ33S anomalism was observed. The initial 87Sr/86Sr and 147Sm/143Nd ratios of most of the Nova-Bollinger igneous rocks have an age of formation of 1300 Ma, which is similar to those of CHUR1300Ma and record limited contamination by lower continental crustal material. The country rocks of the Snowys Dam Formation, locally enriched in iron and sulfur, are likely candidates as crustal contaminants. These metasedimentary sulfides show similar ranges in values for both δ34S and Δ33S to the ores, but their Sr isotopic range is greater than observed in the host intrusions at Nova-Bollinger and in most of the other sampled intrusions. Bollinger globular sulfides with ɛSr values of 63.1 and 144.5 and ɛNd values of −5.7 and −1.8 are suggestive of localised crustal contamination from adjacent wall rock marbles, but otherwise high ɛSr country rocks do not appear to have been dominant contaminants. Bulk assimilation of the country rocks, as modelled in both silicate and sulfide portions of the system, of up to 30% contamination of a primitive mantle melt by siliceous country gneisses, would have been sufficient to produce the degree of crustal contamination recorded in the Nova-Bollinger ores, and more regionally within the Fraser gabbros. Beyond indications that S was crustally derived, it is not possible to identify a specific source, but Snowys Dam sediments are the most likely. There is no compelling evidence for Archean S in the ores, unsurprisingly given the mid-Proterozoic age. It is likely that much of the contamination of the magma and generation of sulfide liquid took place during lateral flow through linked sill complexes within the deeply buried Snowys Dam metasediments, prior to the emplacement of the magmas to form the orebodies. Nova-Bollinger Ni–Cu–Co sulfide ores have δ34S values between +1.6 and +8.0‰ VCDT, with a median value of +2.3‰ VCDT, anomalous relative to uncontaminated mantle values but similar to the range in the country rock metasediments. Values are consistent with equilibration of sulfide xenomelts at R factors of 200–700. There is no detectable mass-independent fractionation of δ33S in the Nova-Bollinger ores. The initial 87Sr/86Sr and 147Sm/143Nd ratios of most of the Nova-Bollinger igneous rocks at the age of formation of 1300 Ma are similar to those of CHUR1300 Ma and record contamination of a primitive mantle melt by up to 30% lower continental crustal material. Unusual globular ores at Bollinger have anomalous ɛSr indicating localised contamination from adjacent wall rock marble; however, this contamination is not pervasive through the orebody. It is likely that much of the contamination of the magma and generation of sulfide liquid took place during lateral flow through linked sill complexes within the deeply buried Snowys Dam metasediments, prior to the emplacement of the magmas to form the orebodies. [ABSTRACT FROM AUTHOR]

Zircon Hf isotopic mapping has been proposed to image large‐scale lithospheric architecture. Here we present zircon Hf isotope maps of the Proterozoic Albany–Fraser Orogen (AFO) in Western Australia, which records a protracted geological history in both extensional and compressional tectonic regimes. The spatial variation in Hf isotope composition of AFO granites is nearly orthogonal to the dominant crustal fabric. Although the 176Hf/177Hf compositions are too juvenile to represent direct melts of the Archaean basement, the variability in 176Hf/177Hf in these AFO magmatic rocks closely mimics the structure of the adjoining Yilgarn Craton. This orogen‐parallel heterogeneity is best illustrated during earliest Palaeoproterozoic magmatic events, which are characterised by low Sr/Y ratios, consistent with tectonic models involving relatively uniform extension along the craton margin during the Palaeoproterozoic. These results demonstrate that regional‐scale zircon Hf variability does not always image coeval lithospheric architecture, but may help illuminate deep basement structure in regions with complex deformation histories. [ABSTRACT FROM AUTHOR]

Currently, protein‐coding de novo variants and large copy number variants have been identified as important for ~30% of individuals with autism. One approach to identify relevant variation in individuals who lack these types of events is by utilizing newer genomic technologies. In this study, highly accurate PacBio HiFi long‐read sequencing was applied to a family with autism, epileptic encephalopathy, cognitive impairment, and mild dysmorphic features (two affected female siblings, unaffected parents, and one unaffected male sibling) with no known clinical variant. From our long‐read sequencing data, a de novo missense variant in the KCNC2 gene (encodes Kv3.2) was identified in both affected children. This variant was phased to the paternal chromosome of origin and is likely a germline mosaic. In silico assessment revealed the variant was not in controls, highly conserved, and predicted damaging. This specific missense variant (Val473Ala) has been shown in both an ortholog and paralog of Kv3.2 to accelerate current decay, shift the voltage dependence of activation, and prevent the channel from entering a long‐lasting open state. Seven additional missense variants have been identified in other individuals with neurodevelopmental disorders (p = 1.03 × 10−5). KCNC2 is most highly expressed in the brain; in particular, in the thalamus and is enriched in GABAergic neurons. Long‐read sequencing was useful in discovering the relevant variant in this family with autism that had remained a mystery for several years and will potentially have great benefits in the clinic once it is widely available. [ABSTRACT FROM AUTHOR]

The West Burma Terrane (WBT) is a small terrane bounded to the east by the Asian Sibumasu Block and to the west by the Indo‐Burman Ranges (IBR), the latter being an exhumed accretionary prism that formed during subduction of Indian oceanic lithosphere beneath Asia. Understanding the geological history of the WBT is important for reconstruction of the closure history of the Tethys Ocean and India‐Asia collision. Currently there are major discrepancies in the proposed timings of collision between the WBT with both India and Asia; whether the WBT collided with India or Asia first is debated, and proposed timings of collisions stretch from the Mesozoic to the Cenozoic. We undertook a multi‐technique provenance study involving petrography, detrital zircon U‐Pb and Hf analyses, rutile U‐Pb analyses and Sr‐Nd bulk rock analyses on sediments of the Central Myanmar Basins of the WBT. We determined that the first arrival of Asian material into the basin occurred after the earliest late Eocene and by the early Oligocene, thus placing a minimum constraint on the timing of WBT‐Asia collision. Our low temperature thermochronological study of the IBR records two periods of exhumation, in the early‐middle Eocene, and at the Oligo‐Miocene boundary. The Eocene event may be associated with the collision of the WBT with India. The later event at the Oligo‐Miocene boundary may be associated with changes in wedge dynamics resulting from increased sediment supply to the system; however a number of other possible causes provide equally plausible explanations for both events. Plain Language Summary: Closure of the ancient Tethys Ocean by collision of various continental fragments culminated in the formation of the Himalayan mountain belt. A knowledge of the timing of collision of the various terranes is important to reconstruct the geological history of the region. The timing of the collision of the West Burma Terrane with both India and Asia is debated. We show that material eroded from Asia is first recorded in the Central Myanmar Basin of the West Burma Terrane after the earliest late Eocene and by the early Oligocene, providing a minimum time of docking of these continental fragments. We show two periods of exhumation of the exhumed accretionary prism of the Indo‐Burman Ranges, in the early‐middle Eocene and at the Oligo‐Miocene boundary. These events may be associated with the collision of the West Burma Terrane and India, and changes in wedge dynamics, respectively, but other causes are equally plausible. Key Points: First arrival of Asian detritus into the Central Myanmar Basin occurred after the earliest late Eocene and by the early Oligocene, thus constraining the time of WBT‐Asia collisionOur low temperature thermochronological study of the Indo‐Burman Ranges indicates exhumation in the early‐mid Eocene and around the Oligo‐Miocene boundary [ABSTRACT FROM AUTHOR]

Hydrothermal venting at the Lucky Strike hydrothermal field, located on the Mid‐Atlantic Ridge, is associated with faulting linked to the tectonic dismemberment of a central axial volcano. Radium‐226/Ba dating of hydrothermal barite indicates that hydrothermal venting is at least 6,600 years old, and that Lucky Strike is one of the youngest known vent fields on the Mid‐Atlantic Ridge, which typically have ages exceeding 20 ka. Deposit volume calculations indicate that the total accumulated mass of the hydrothermal deposits on the seafloor at Lucky Strike is ∼1.3 ± 0.2 Mt, and that this mass accumulated at a maximum average rate of 194 ± 28 t/yr. This accumulation rate is comparable to other well characterized mid‐ocean ridge hydrothermal sites, such as TAG and Endeavor, but at Lucky Strike is concentrated within a relatively small area of <2.5 km2. Plain Language Summary: In this contribution we determine the age (>6,600 years) and mass (∼1.3 Mt) of metal‐rich deposits that formed at a cluster of high‐temperature seafloor hot springs called Lucky Strike, which is situated on the Mid‐Atlantic Ridge. With this information we calculate the average rate of formation (194 t/yr) of these deposits. Our results indicate that the Lucky Strike vent field is much younger than other vent fields that also occur along the Mid‐Atlantic Ridge, but the deposits form at similar rates, which are high when compared to other types of geological processes that produce metal‐rich deposits. Key Points: Hydrothermal activity at the Lucky Strike vent field has been ongoing for at least 6,600 yearsAn estimated ∼1.3 Mt of hydrothermal material has accumulated on the seafloor over an area of <2.5 km2 of seafloor, at a rate of ∼194 t/yrAccumulation rates from Lucky Strike are comparable to other seafloor sites and to analogous on‐land volcanogenic massive sulfide deposits [ABSTRACT FROM AUTHOR]

End-stage Fontan patients with single-ventricle (SV) circulation are often bridged-to-heart transplantation via mechanical circulatory support (MCS). Donor shortage and complexity of the SV physiology demand innovative MCS. In this paper, an out-of-the-box circulation concept, in which the left and right ventricles are switched with each other is introduced as a novel bi-ventricle MCS configuration for the "failing" Fontan patients. In the proposed configuration, the systemic circulation is maintained through a conventional mechanical ventricle assist device (VAD) while the venous circulation is delegated to the native SV. This approach spares the SV and puts it to a new use at the right-side providing the most-needed venous flow pulsatility to the failed Fontan circulation. To analyze its feasibility and performance, eight SV failure modes have been studied via an established multi-compartmental lumped parameter cardiovascular model (LPM). Here the LPM model is experimentally validated against the corresponding pulsatile mock-up flow loop measurements of a representative 15-year-old Fontan patient employing a clinically-approved VAD (Medtronic-HeartWare). The proposed surgical configuration maintained the healthy cardiac index (3-3.5 l/min/m 2 ) and the normal mean systemic arterial pressure levels. For a failed SV with low ejection fraction (EF = 26%), representing a typical systemic Fontan failure, the proposed configuration enabled a ~ 28 mmHg amplitude in the venous/pulmonary waveforms and a 2 mmHg decrease in the central venous pressure (CVP) together with acceptable mean pulmonary artery pressures (17.5 mmHg). The pulmonary vascular resistance (PVR)-SV failure case provided a ~ 5 mmHg drop in the CVP, with venous/pulmonary pulsatility reaching to ~ 22 mmHg. For the high PVR failure case with a healthy SV (EF = 44%) pulmonary hypertension is likely to occur as expected. While this condition is routinely encountered during the heart transplantation and managed through pulmonary vasodilators a need for precise functional assessment of the spared failed-ventricle is recommended if utilized in the PVR failure mode. Comprehensive in vitro and in silico results encourage this novel concept as a low-cost, more physiological alternative to the conventional bi-ventricle MCS pending animal experiments., (© 2023. The Author(s) under exclusive licence to Biomedical Engineering Society.)

Large and turbid rivers have varying temperatures, light conditions, nutrient availability, and nutrient ratios that may affect phytoplankton communities and occur within a changing world of point and nonpoint source nutrient loadings. We investigated how these physical and chemical factors affect Chlorophyll a (Chl a) concentrations in the Mississippi River, the largest river in North America, by sampling 878 times from February 1997 to December 2018 near its terminus at Baton Rouge, Louisiana. We hypothesized that nutrient concentrations and ratios were significant factors limiting phytoplankton biomass accumulations in this turbid river. The Chl a concentrations were in the "poor" water quality category when above 20 μg Chl a L−1 12% of the time. Two percent of the samples were > 40 μg Chl a L−1 and occurred on declining discharges. Results from graphical analysis and a principal component regression analysis showed that the highest Chl a values were constrained to when dissolved silicate: dissolved inorganic nitrogen (DIN) molar ratios < 1 : 1 and dissolved DIN : phosphate molar ratios < 16 : 1, which is when the phytoplankton community likely consists of non‐siliceous phytoplankton. Increasing light conditions and reducing turbulence, which happens when river water is diverted into calmer and shallower waters, will create a phytoplankton bloom—perhaps becoming a harmful algal bloom—as has happened previously. [ABSTRACT FROM AUTHOR]

The Aqishan lead‐zinc deposit, located in the Jueluotag metallogenic belt of eastern Tianshan, Xinjiang, Northwest China, has a stratiform occurrence in the marine volcanic tuff of the Yamansu Formation. The ore body has a typical double‐layer structure, having a stratified, stratoid, lenticular upper part and a veined, stockwork‐like lower part. The occurrence of the upper orebody is consistent with that of the volcanic tuff wall rock. The ore minerals are mainly chalcopyrite, pyrite, sphalerite, galena and magnetite, the altered minerals mainly being silicified, such as sericite, chlorite, epidote, garnet. The garnetized skarn, being stratiform and stratoid, is closely related to the upper part of the orebody. Geological observations show that the limestone in the ore‐bearing Yamansu Formation is not marbleized and skarnized. Spatially, it is associated with the ferromanganese deposits in the marine volcanic rocks of the Yamansu Formation. These geological features reflect the likelihood that the Aqishan lead‐zinc deposit is a hydrothermal exhalation sedimentary deposit. The results from the EPMA show that the garnet is mainly composed of grossular–andradite series, contents being in a range of 34.791–37.8% SiO2, 32.493–34.274% CaO, 8.454–27.275% FeO, 0.012–15.293% Al2O3, 0.351–1.413% MnO, and lower values of 0.013–1.057% TiO2. The content of SiO2 vs. CaO and FeO vs. Al2O3 has a significant positive correlation. The results of ICP‐MS analysis for the garnet show that the REE pattern is oblique to right in general. The total amount of rare earth elements is relatively low, ΣREE = 71.045–826.52 ppm, which is relatively enriched for LREE and depleted for HREE. LREE/HREE = 8.66–4157.75, LaN/YbN = 23.51–984.34, with obvious positive Eu and Ce anomalies (δEu = 2.27–76.15, δCe = 0.94–1.85). This result is similar to the REE characteristics of ore‐bearing rhyolite volcanic rocks, showing that the garnet was formed in an oxidizing environment and affected by clear hydrothermal activity. The U‐Pb isotopic dating of garnet by fs‐LA‐HR‐ICP‐MS gives an age of 316.3 ± 4.4 Ma (MSWD = 1.4), which is consistent with the formation time of the Yamansu Formation. According to the study of deposit characteristics and geochemical characteristics, this study concludes that the Aqishan lead‐zinc deposit is a hydrothermal exhalation sedimentary deposit, the garnet being caused by hydrothermal exhalative sedimentation. [ABSTRACT FROM AUTHOR]

The Mogok metamorphic belt (MMB) in central Myanmar is well known for its complex tectonics, magmatism, and metamorphism in the framework of Tethyan subduction and India–Asia collision. It is also world renowned due to the gemstone‐class rubies and sapphires. Identification and discrimination of those petrological units in this region therefore are important for understanding the gemstone mineralization. Ultramafic massifs also crop out together with the gemstone‐bearing metamorphic rocks in the MMB. It is still poorly constrained about their origin (i.e., mantle peridotites of Jurassic–Cretaceous ophiolites or cumulate rocks) and their relationship with the gemstone generation. Here, we report petrological and geochemical data for the Mogok ultramafic rocks. Petrographic observations show that they have typical cumulate textures, with a crystallization order of olivine/spinel‐orthopyroxene‐clinopyroxene. They have low whole‐rock Al2O3 and CaO, and extremely high spinel Cr# (=Cr/[Cr + Al]; up to 0.86). Clinopyroxenes of these rocks show light rare earth element enriched patterns when normalized to CI chondrite. The results suggest that the Mogok ultramafic rocks have different compositions, both whole‐rock and mineral, from mantle peridotites of Myanmar ophiolites, such as the Kalaymyo and Myitkyina ophiolites, but resemble typical Alaskan‐type ultramafic cumulates. Therefore, the Mogok ultramafic rocks are cumulates generated by high‐pressure crystallization of hydrous arc melts, probably during the subduction of the Tethyan oceanic slab. We argue that the emplacement of these arc melts may have provided additional heat for the earlier magmatic rocks and regional high‐temperature metamorphism, although there is a need to further constrain the ages of these rocks. This, along with magmatism and metamorphism during post‐collisional extension, probably collectively contributed to the generation of world‐class coloured gemstone mineralization. [ABSTRACT FROM AUTHOR]

Numerous medical devices have been applied for the treatment or alleviation of various diseases. Tribological issues widely exist in those medical devices and play vital roles in determining their performance and service life. In this review, the bio-tribological issues involved in commonly used medical devices are identified, including artificial joints, fracture fixation devices, skin-related devices, dental restoration devices, cardiovascular devices, and surgical instruments. The current understanding of the bio-tribological behavior and mechanism involved in those devices is summarized. Recent advances in the improvement of tribological properties are examined. Challenges and future developments for the prospective of bio-tribological performance are highlighted. [ABSTRACT FROM AUTHOR]