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Seismological Characterization of Northern Hikurangi Margin Slow Slip Regions Associated With Normal Faults, Seamounts, and Seeps
Full text linkAbstract At the northern Hikurangi margin, Aotearoa New Zealand, slow slip events (SSEs) recur every 6–24 months to 30 km depth. Although shallow SSEs (0–10 km) are well‐studied offshore, the deeper portion (10–30 km) remains poorly understood, limiting insight into SSE initiation. Here we investigate this deeper region and examine relationships between newly resolved SSEs and seismicity. Using time‐dependent inversions, we resolve two small SSEs ( 6.2 and 6.4), including one that extends from 15 to 30 km depth. Using data from a dense onshore seismograph network deployed directly above this deeper portion from December 2017 to October 2018, we construct a catalog of 3,071 high‐quality earthquakes with hypocentral uncertainties 5 km, located using a 3‐D velocity model and a new 1‐D model. Earthquake magnitudes range from −0.84 to 4.40, with a completeness magnitude of 1.7 and a b‐value of 1.06. Focal mechanisms reveal numerous normal‐faulting earthquakes, including some within the slab mantle. Vertically‐aligned seismicity and normal‐faulting earthquakes outline pathways linking the slab mantle to surface seeps of mantle‐derived fluids. We infer that normal faults form due to slab bending and localized uplift of subducting seamounts, which roughen the plate interface, damage the upper plate, and promote fluid migration. Landward of 100 km from the trench, both surface seeps and normal‐faulting mechanisms cease, coinciding with the downdip limit of shallow SSEs. Together, these results suggest that the Hikurangi margin's rough subducting plate interface exerts strong control on forearc dewatering and SSE genesis.
Plain Language Summary At the northern Hikurangi margin subduction zone, Aotearoa New Zealand, the Pacific Plate periodically slips slowly beneath the Australian Plate during slow‐slip events (SSEs). While shallow SSEs offshore are well‐studied, the deeper part (10–30 km) is harder to observe. In this study, we use a dense network of land‐based seismographs to examine two SSEs and the earthquakes that accompanied them. Our new earthquake catalog contains over 3,000 well‐located earthquakes. Some of these earthquakes show normal‐faulting mechanisms, some deep within the subducting slab. These normal faults and vertical clusters of earthquakes trace pathways that allow fluids to rise upwards from the slab mantle. These pathways connect to surface seep sites where mantle‐derived fluids are observed, demonstrating a link between deep slab processes and surface features. The seeps and the normal‐faulting earthquakes disappear farther inland, matching the downdip limit of shallow SSEs. We suggest that normal faults develop due to slab bending and localized uplift of subducting seamounts. These damage the upper plate and help fluids migrate upwards. Together, these findings show that the roughness of the subducting Pacific Plate plays a key role in controlling fluid flow and the depth range of slow slip behavior at the Hikurangi margin.
Key Points Dense onshore seismic and geodetic data resolve two Hikurangi SSEs, including an unusually deep 15–30 km event Normal fault networks, developed due to a rough, seamount‐rich subduction plate interface, form fluid pathways from slab mantle to surface Down‐dip limit of SSEs is where surface seeps and normal‐faulting ends: rough plate interface controls forearc dewatering and SSE genesi
Gestational low-protein diet impairs mitochondrial function and skeletal muscle development by inducing immune responses in male offspring.
Full text linkMaternal nutrition is essential for proper fetal and postnatal organ maturation and is linked to the future risk of developing metabolic syndrome, cardiovascular disease, and muscle loss. There is still limited understanding how a low-protein intake during gestation influences skeletal muscle development, inflammation, and the related pathways. This study aimed to investigate the impact of gestational low-protein diet in mice on skeletal muscle development and inflammatory responses in male offspring. Pups born from mothers fed a low-protein diet (LPD) were lactated by normal protein diet (NPD)-fed mothers and maintained on NPD post-weaning (LNN group). Offspring born from mothers fed an NPD and maintained on an NPD during lactation and beyond were used as controls (NNN group). In 21-day-old offspring from protein-restricted mothers, RNA-Seq analysis showed upregulation of immune response-related genes, enriching adaptive immunity pathways. Additionally, LNN group exhibited elevated markers of inflammation, along with disruptions in antioxidant defence balance and macrophages infiltration in gastrocnemius muscle at 3 months of age. Energy metabolism was impaired, as indicated by changes in related proteins and enzymes involved in mitochondrial function. We conclude that gestational LPD adversely affects skeletal muscle development in male offspring
Approximate quantum circuit compilation for proton-transfer kinetics on quantum processors.
Full text linkProton transfer reactions are central to chemical and biological systems, where quantum effects-such as tunneling, delocalization, and zero-point motion-critically influence reaction kinetics. Classical methods that capture these phenomena scale poorly with system size, limiting their applicability. Here, we extend and benchmark a quantum computing framework based on the Nuclear-Electronic Orbital formalism, treating the transferring proton quantum mechanically, to assess the feasibility of computing accurate energy barriers on current quantum devices. Using malonaldehyde as a prototypical system, we construct deep initial circuits via ADAPT-VQE combined with the frozen natural orbital approximation and apply adaptive approximate quantum compiling to balance circuit depth and fidelity. Transpiling these circuits for the ibm_pittsburgh device and simulating with realistic noise models, we compute barrier heights and delocalized proton densities along the reaction pathway. Circuit refinement and compression yield compact representations that preserve essential quantum features of the transfer process. Notably, our shallowest circuits (AQC-low) reproduce key qualitative features, such as proton density localization, and are near the frontier of feasibility for current hardware. In contrast, deeper circuits (AQC-high) retain higher fidelity to reference barrier height, reducing the error to 1.6 mHa (13%) while still yielding a 98% underestimation of the rate constant at 120 K
Early synaptic pathology is associated with small tau aggregates in Alzheimer's disease.
Full text linkAlzheimer's disease (AD) is phenotypically characterised by progressive memory loss, which has been linked to tau aggregation and synaptic dysfunction. Here we characterised the nanoscopic tau aggregates in individual synaptosomes from AD cases and controls, measuring their number and size using SynPull with direct stochastic optical reconstruction microscopy (dSTORM). A total of 7888 synaptosomes from pre-frontal cortex samples were studied, showing the presence of AT8-positive tau aggregates in a small fraction of synaptosomes (~ 3%) from control brains, reaching ~ 20% by Braak stage 6. These key findings of the intra-synaptic localisation of aggregates and existence of synaptic tau pathology at Braak stage 3-preceding tangle formation in this region, were confirmed using aggregate-specific single-molecule array (SIMOA) with proteinase K digestion, three-dimensional super-resolution microscopy, stimulated emission depletion microscopy (STED), and immunohistochemistry. The aggregates also grew in size with AD progression with an average length of 117 nm at stage 0, 154 nm at stage 3 and 182 nm at stage 6, however they mostly remained non-elongated (circular) with average eccentricity values remaining below 0.8. We then investigated the multi-phosphorylation of synaptic tau aggregates for AT8 and T181 and quantified their co-localisation with phosphatidylserine and CD47, synaptic "eat me" and "don't eat me" signals respectively, along with synaptogyrin-3, which contributes to tau-mediated synaptic dysfunction. T181, phosphatidylserine, and synaptogyrin-3 co-localisation with AT8-positive tau were higher during stage 3 and CD47 was lower, indicating early synaptic pathology is associated with the formation of small tau aggregates, contributing to microglia-driven synaptic loss
Prevalence of structural and idiopathic epilepsy in brachycephalic and non-brachycephalic dogs in the context of the International Veterinary Epilepsy Task Force guidelines.
Full text linkOBJECTIVES: To report the relative prevalence of structural and idiopathic epilepsy in brachycephalic and non-brachycephalic breeds in the context of the International Veterinary Epilepsy Task Force guidelines. A secondary objective was to compare the age at diagnosis of structural epilepsy in brachycephalic and non-brachycephalic dogs. MATERIALS AND METHODS: Medical records were reviewed retrospectively for dogs presenting to a single centre for investigation of generalised seizures. Patients were categorised based upon skull conformation, age, interictal neurological examination and the presence of structural lesions identified on magnetic resonance imaging that were deemed likely to cause seizures. Descriptive statistics, the Mann-Whitney U test and Bayesian analysis of the data were performed to investigate the associations between skull conformation, the presence of structural lesions and the age of onset of structural epilepsy. RESULTS: A structural lesion was identified as the probable cause of seizures in 34.2% (38/111) of dogs. 61.8% of brachycephalic dogs had a structural lesion compared to 22.1% of non-brachycephalic dogs. 33.3% of brachycephalic dogs aged 6 months to 6 years with a normal interictal neurological examination were diagnosed with a structural lesion compared to 0% of non-brachycephalic dogs in this age category. The median age at diagnosis of structural epilepsy in brachycephalic dogs (60 months) differed significantly from that of non-brachycephalic dogs (108 months). CLINICAL SIGNIFICANCE: Brachycephaly was identified as a risk factor for structural epilepsy in this study population, suggesting that magnetic resonance imaging of the brain and cerebrospinal fluid analysis should be more strongly considered in brachycephalic dogs who otherwise satisfy a tier I confidence level diagnosis of idiopathic epilepsy, independent of the interictal neurological examination
Structural Interconversions and Guest Binding Properties of Tetrakis(formylpyridine)-Based Pseudo -Cubic and Trigonal-Prismatic Metal–Organic Capsules
Full text linkHere, we report a new tetrakis(formylpyridine) subcomponent that was designed to assemble with anilines and ZnII to afford a set of structurally distinct metal–organic cage structure types. By modulating the metal-to-ligand stoichiometry, we obtained a pseudo-cubic Zn8L6 cage and an open Zn6L3 trigonal prism, the former featuring a diastereomeric configuration of faces and vertices that had not been previously observed. Addition of a tritopic subcomponent yielded a Zn6L3L′2 heteroleptic capped trigonal prism, which could also be prepared via a combination of the homoleptic cages formed by the two individual ligands. The capped trigonal prism encapsulated the pollutant perfluorobutanesulfonate and the oxidant tetracyanoquinodimethane, both technologically relevant guests
Coesite Discovery in Eclogites Confirms UHP Metamorphism in the Orlica‐Śnieżnik Dome (SW Poland)
Full text linkABSTRACT Eclogite lenses are exposed within the orthogneiss‐dominated core of the Orlica‐Śnieżnik Dome in the Sudetes, which forms the northeastern margin of the Bohemian Massif (Variscan Belt of Central Europe). The presence of coesite inclusions in garnet and omphacite confirms that these eclogites underwent ultrahigh‐pressure metamorphism. This interpretation is further supported by phase equilibria modelling, which indicates peak‐pressure metamorphic conditions of 2.9–3.2 GPa and 750°C–830°C. The results are consistent with estimates derived from conventional geothermobarometry and Zr‐in‐rutile thermometry applied to rutile inclusions in garnet. Based on quartz‐in‐garnet elastic barometry, a maximum entrapment pressure of approximately 2.0 GPa is obtained. We interpret this discrepancy as a result of viscous relaxation of garnet at high temperature. The first stage of re‐equilibration during decompression occurred at a pressure of 2.0–2.2 GPa and a temperature of 680°C–770°C. The observed rock associations exhibit similarities to other UHP occurrences within the Saxo‐Thuringian Zone, suggesting a comparable exhumation mechanism. This likely involved initial buoyancy‐driven exhumation within a subduction channel, followed by crustal‐scale folding. Furthermore, the maximum pressure recorded in the eclogites may partly reflect nonlithostatic components, such as transient pressure variations arising from rheological heterogeneity between the eclogites and their host rocks
Search for single production of vector-like quarks decaying into W(ℓν)b in pp collisions at s=13 TeV with the ATLAS detector
Full text linkA search for single production of a vector-like quark Q, which could be either a singlet T, with charge 23, or a Y from a (T, B, Y) triplet, with charge −43, is performed using data from proton-proton collisions at a centre-of-mass energy of 13 TeV. The data correspond to the full integrated luminosity of 140 fb−1 recorded with the ATLAS detector during Run 2 of the Large Hadron Collider. The analysis targets Q → Wb decays where the W boson decays leptonically. The data are found to be consistent with the expected Standard Model background, so upper limits are set on the cross-section times branching ratio, and on the coupling of the Q to the Standard Model sector for these two benchmark models. Effects of interference with the Standard Model background are taken into account. For the singlet T, the 95% confidence level limit on the coupling strength κ ranges between 0.22 and 0.52 for masses from 1150 to 2300 GeV. For the (T, B, Y) triplet, the limits on κ vary from 0.14 to 0.46 for masses from 1150 to 2600 GeV
Hi-reComb: constructing recombination maps from bulk gamete Hi-C sequencing
Full text linkRecombination is central to genetics and to evolution of sexually reproducing organisms. However, obtaining accurate estimates of recombination rates, and of how they vary along chromosomes, continues to be challenging. To advance our ability to estimate recombination rates, we present Hi-reComb, a new method and software for estimation of recombination maps from bulk gamete chromosome conformation capture sequencing (Hi-C). Simulations show that Hi-reComb produces robust, accurate recombination landscapes. With empirical data from sperm of five fish species we show the advantages of this approach, including joint assessment of recombination maps and large structural variants, map comparisons using bootstrap, and workflows with trio phasing vs. Hi-C phasing. With off-the-shelf library construction and a straightforward rapid workflow, our approach will facilitate routine recombination landscape estimation for a broad range of studies and model organisms in genetics and evolutionary biology. Hi-reComb is open-source and freely available at https://github.com/millanek/Hi-reComb