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This paper presents a first implementation of gradient, divergence, and particle tracing schemes for the EMC3 code, a stochastic 3D plasma fluid code widely employed for edge plasma and impurity transport modeling in tokamaks and stellarators. These schemes are essential to accommodate plasma drift computations, which are currently absent in the code. Plasma drifts have been recognized to significantly influence transport of particles and energy, and their inclusion in future code upgrades will substantially enhance the code's predictive capabilities. For gradient and divergence calculations, we introduce a second‐order least‐squares gradient scheme. We confirm the second‐order convergence properties and assess the accuracy of several analytical test cases in the presence of synthetic noise. In the second part of this paper, we employ the validated gradient scheme in a fourth‐order Runge–Kutta particle tracing scheme to trace a particle through a generic drift velocity field. The impact of synthetic noise on the scheme's performance is investigated by evaluating various error metrics. We find that the implemented schemes function as intended and exhibit sufficient accuracy to enable drift computations. [ABSTRACT FROM AUTHOR]

A detailed operando DRIFTS study on the CO2 Fischer‐Tropsch reaction with K‐promoted Fe/YZrOx catalysts was performed to investigate the influence of this modification on the catalytic performance in the formation of lower olefins as well as higher hydrocarbons and to gain insights into mechanistic aspects. Catalytic testing revealed an enhanced formation of olefins and hydrocarbons by adding potassium to the catalysts, while spectroscopic studies revealed various stable adsorbates and intermediates such as monodentate carbonates, bicarbonates, formates, formyl, and methoxy on the surface of the K‐promoted Fe/YZrOx catalysts compared to the unpromoted one. Based on gas‐feed switching experiments and statistical analysis of literature IR data regarding Fe‐containing catalysts, it was found that carbonate species interacting with H2 are transformed to higher hydrocarbons and methane via formate and formyl formation, while bicarbonate species are decomposed accompanied by the formation of CO, which then further reacts to form formate or formyl and finally hydrocarbons. [ABSTRACT FROM AUTHOR]

Gallium oxide‐based catalysts are promising candidates for CO2 hydrogenation to methanol, whilst mechanistic understanding of the catalytic systems is not yet fully understood. Here, transient in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) studies of CO2 hydrogenation over the unsupported CuGa and CuGaN (with N doping) catalysts were conducted. The findings show that N doping could possibly promote the formation of surface Cu+ sites on the interface between Cu and Ga2O3, and hence increasing the selectivity to methanol. However, N doping prohibited the reduction of Ga2O3 to oxygen‐deficient Ga2O3‐x, which is unfavorable for CO2 conversion. Additionally, during DRIFTS the steady‐state isotope transient kinetic analysis (SSITKA) was performed (under H2/D2 isotopic switching conditions). The SSITKA results confirm that the Cu+‐bound formates were likely the key intermediates for methanol synthesis over the catalyst, and the N doping could also weak the interaction between CO* species and the catalyst surface, and thus facilitating the selectivity towards methanol rather than CO. Findings of the work show that the partial nitridation of the metal oxides could be the strategy to promote methanol synthesis selectivity. [ABSTRACT FROM AUTHOR]

Tungsten (W) impurity eroded from the divertor target can degrade the confinement performance of future fusion reactors. The mechanism of the effect of E × B drift on the W transport in the scrape‐off layer (SOL) was investigated with a fixed cross‐field anomalous particle diffusion coefficient for W ions (D⊥,W) of 1 m2s−1 in our previous simulation work, which indicates that the W flux entering the confined region (Γenter) and mean W concentration in the confined region (CWavg$$ {C}_{\mathrm{W}}^{\mathrm{avg}} $$) can be increased by more than one order of magnitude by drifts. In this work, the influence of the cross‐field anomalous diffusion on the W transport in the SOL is further investigated. The basic flow pattern of the W ion flux (ΓW) keeps when D⊥,W varying from 0.5 to 3 m2s−1, and Γenter mainly comes from the hotter divertor region. Results show that D⊥,W value affects the W leakage from divertor region and entry into confined region. Therefore, Γenter and CWavg$$ {C}_{\mathrm{W}}^{\mathrm{avg}} $$ both decrease with increasing D⊥,W. Mechanisms for cases w/wo drifts are compared. [ABSTRACT FROM AUTHOR]

In this study, we utilize ICON observations from 2019 to 2022 to analyze the variability of vertical plasma drift and its relationship with the neutral winds. The results reveal that there are 19% of downward plasma drifts at 13–17 LT, which changes with seasons and longitudes. The downward plasma drift occurs less frequently compared to the contemporaneous counter electrojet during solstices. We identify the relationship between vertical plasma drifts and north foot magnetic zonal and meridional wind profiles at 90–300 km altitudes. As the vertical plasma drifts become small or downward, the zonal winds display diverse variations at the altitudes; that is, the disturbances are eastward at 95–120 km altitudes, westward at 120–160 km altitudes, and eastward above 180 km altitudes, while the meridional winds present weak changes in all altitudes. Additionally, we discuss the possible roles of the E‐ and F‐region dynamos on the vertical plasma drifts. Plain Language Summary: The neutral wind in the Earth's upper atmosphere drives the ionospheric ions to cross the geomagnetic field lines and produces the dynamo effects in the E‐ and F‐regions. The electric field is created due to the divergence free of the total electrical current. The zonal electric field drives the ionospheric plasma to drift upward and downward due to the horizontal field lines, and influences the structures of low latitude ionosphere. One open question is that the vertical plasma drift shows the significant day‐to‐day variability and sometimes remarkably deviates from the climatological pattern during the quiet times. The ICON satellite provides the simultaneous observations of the plasma drifts and neutral winds in low latitudes, which provides us a good chance to investigate the day‐to‐day variability of the vertical plasma drift and its relationship to the neutral wind, as we discuss in the manuscript. Key Points: The equatorial vertical plasma drifts show large variability and 19% downward plasma drift at 13–17 LTThe occurrence of the downward plasma drift presents a significant longitudinal and seasonal variationsThe E‐ and F‐region zonal winds play vital roles on the large variability and the occurrence of the downward plasma drift [ABSTRACT FROM AUTHOR]

Layered double hydroxide (LDH) nanostructures are commonly used to study the interfacial effects of Pt‐based catalysts in CO oxidation. However, the specific role and detailed intermediates involved in CO oxidation remain unclear. Density functional theory (DFT) predicted that NiFe LDH loaded with single Pt atoms would exhibit satisfactory CO oxidation activity. On this basis, we prepared Pt1NiFe LDH catalysts with various Fe : Ni ratios by using the one‐pot method and achieved favorable dispersion of single Pt atoms. Pt1/FN‐1, which had the optimal Fe : Ni ratio (1 : 1), exhibited satisfactory catalytic performance for CO oxidation and a high turnover frequency, as determined through DFT calculations and experimental characterization. In‐situ diffuse reflectance infrared Fourier transform spectroscopy confirmed that CO directly reacted with Pt1/FN‐1 to produce CO2 and that introduced O2 formed bicarbonate species to produce CO2 together with the adsorbed CO on Pt1 sites. Overall, our work provides new insights into the catalytic mechanism of the well‐known Pt1NiFe LDH catalysts in CO oxidation. [ABSTRACT FROM AUTHOR]

In this work we quantify the representation error of the algorithm Estimating Model Parameters from Ionospheric Reverse Engineering (EMPIRE), which estimates global neutral winds and ion drifts given time‐varying plasma densities. SAMI3 (Sami3 is A Model of the Ionosphere) serves as the background climate model and pseudo‐measurements for the EMPIRE observation system. This configuration allows the data assimilation inputs to be self‐consistent between each other and with the validation data. The estimated neutral winds and ion drifts are compared to the Horizontal Wind Model (HWM14) and SAMI3 "truth." For both the quiet period on 25 August 2018 and subs7equent storm on 26 August, the EMPIRE estimation of ion drifts is better at low‐to‐mid geomagnetic latitudes with mean error up to 20 m/s. For the high latitudes (poleward of ±60° magnetic), the mean errors exceed 50 m/s with variances up to 200 m/s, and the relative errors are higher than the "truth." At latitudes of ±87°, the large errors are attributed to a boundary effect. However, the neutral wind mean errors peak at 20 m/s at mid‐latitudes (40°–60° magnetic), with larger uncertainties, then converge to 0 approaching higher latitudes. By conducting this study, we define a method for obtaining the representation error covariance for future use of EMPIRE with SAMI3 as background. Plain Language Summary: Data assimilation in the field of space weather is a technique that reduces the gap between background model and instrument measurements to estimate the current or future conditions. Data assimilation needs an estimate of the possible errors, to optimize the calculation of atmospheric variables. The model error and measurement errors can be provided by the model data source and instrument. However, another error source, called the representation error, plays an important role. The representation error is due to simplifying reality to a mathematical model that can be run by a computer. In this study, we compute the representation error for a specific data assimilation algorithm (EMPIRE). To achieve this, we use a model‐simulated reality as the truth. We import information from background models to the data assimilation algorithm, then compare the algorithm outputs to the simulated truth of neutral winds and ion drifts. We conclude that the error for ion drifts from the data assimilation is small at the low‐to‐mid latitudes, but much larger at high latitudes. For neutral wind, the error is larger at mid‐latitudes. Key Points: We analyze the representation error in a data assimilation algorithm for a quiet and a storm day in August 2018 with synthetic dataBy validating the ion drift outputs with the self‐consistent input source, EMPIRE yields smaller errors at low‐to‐mid latitudes up to ±60°EMPIRE neutral winds have lower errors at low and high latitudes, and at southern mid‐latitudes differ from the quiet to storm day [ABSTRACT FROM AUTHOR]

Pd/BEA is chosen as a model passive NOx adsorber (PNA) to elucidate the effect of the feed gas composition on the NOx adsorption/desorption behavior. The Brønsted acid and the partially hydrolyzed framework Al (P‐HAl(OH)) sites in HBEA adsorb NO and NO2 under dry conditions. Moreover, the performance of HBEA is not affected by CO, while CO inhibits nitrate formation and promotes NO adsorption via the Pd(NO)(CO) complexes formation over Pd/BEA. H2O inhibits NO adsorption over the Brønsted acid and P‐HAl(OH) sites, and ionic Pd is the only active site for NOx adsorption under wet conditions. Furthermore, NO adsorption over hydrated Pd (Pd2+(OH)(NO)(H2O)3) is weaker than NO adsorption over bare ionic Pd (Z2[Pd2+(NO)], Z[Pd2+(OH)(NO)]). Dehydration of Pd2+(OH)(NO)(H2O)3 forms more stable Z[Pd2+(OH)(NO)] during desorption. The NO adsorption capacity of Pd/BEA improves in the presence of CO under both dry and wet conditions by forming a stable carbonyl–nitrosyl complex. [ABSTRACT FROM AUTHOR]

The vibrational‐translational (VT) excitation of nitrogen molecules led by collisions with fast ions in subauroral ion drifts (SAID) has been conceived as a potential underlying mechanism contributing to the formation of the Strong Thermal Emission Velocity Enhancement (STEVE) phenomenon (Harding et al., 2020, https://doi.org/10.1029/2020gl087102). In this study, we perform quantum calculations of the VT excitation rates of N2 led by fast‐drifting ions, and evaluate the resulting vibrational distribution of N2 with ionospheric/thermospheric parameters expected under intense SAID condition. We conclude that, while the VT energy transfer led by SAID plays a distinguishable role in the vibrational excitation of N2, it is incapable of populating the high vibrational levels to the required concentration (Harding et al., 2020, https://doi.org/10.1029/2020gl087102) to produce adequate nitric oxide density, and in turn the nitrogen‐dioxide continuum intensity, to account for the STEVE brightness. Plain Language Summary: A night sky phenomenon known as STEVE has captured the attention of scientists and citizen scientists in recent years. It is known that STEVE is inherently related to a special process termed "subauroral ion drifts (SAID)", namely a rapid westward drift of plasma in the Earth's ionosphere. It was thus hypothesized that a collision between fast ions and the nitrogen molecules (N2) may cause the kinetic energy of ions being transferred to the internal energy of N2, which can facilitate the chemical reactions leading to STEVE emissions. In this study, we perform quantum calculations of the energy transfer between fast ions and N2 and conclude that, such energy transfer is inefficient under realistic SAID conditions and incapable of accounting for the STEVE emission. Key Points: We perform quantum calculations of the vibrational‐translational (VT) excitation rates of nitrogen molecules (N2) led by fast‐drifting ionsWe calculate the N2 vibrational distribution including VT excitation with ionospheric/thermospheric parameters expected under SAID conditionWe assess that VT excitation led by SAID is unable to provide adequate high‐level excited N2 population to account for the STEVE brightness [ABSTRACT FROM AUTHOR]

A coronal mass ejection erupted from the Sun on 21 April 2023 and created a G4 geomagnetic storm on 23 April. NASA's global‐scale observations of the limb and disk (GOLD) imager observed bright equatorial ionization anomaly (EIA) crests at ∼25° Mlat, ∼11° poleward from their average locations, computed by averaging the EIA crests during the previous geomagnetic quiet days (18–22 April) between ∼15°W and 5°W Glon. Reversed C‐shape equatorial plasma bubbles (EPBs) were observed reaching ∼±36° Mlat (∼40°N and ∼30°S Glat) with apex altitudes ∼4,000 km and large westward tilts of ∼52°. Using GOLD's observations EPBs zonal motions are derived. It is observed that the EPBs zonal velocities are eastward near the equator and westward at mid‐latitudes. Model‐predicted prompt penetration electric fields indicate that they may have affected the postsunset pre‐reversal enhancement at equatorial latitudes. Zonal ion drifts from a defense meteorological satellite program satellite suggest that westward neutral winds and perturbed westward ion drifts over mid‐latitudes contributed to the observed latitudinal shear in zonal drifts. Plain Language Summary: A severe geomagnetic storm occurred on 23 April 2023. The effects of the storm on the nighttime equatorial and mid‐latitude ionosphere are investigated using NASA's global‐scale observations of the limb and disk (GOLD) measurements. GOLD observed bright, widely separated equatorial ionization anomaly (EIA) crests between ∼15°W and 5°W Glon. Extreme equatorial plasma bubbles (EPBs) reaching mid latitudes at ∼40 N and ∼30°S Glat with apex altitudes of ∼4,000 km at the magnetic equator were observed over these longitudes. The EPBs velocities were eastward at low latitudes, between the EIA crests, and reversed to westward near mid‐latitudes. At mid‐latitudes EPBs showed westward tilts that were larger than previous observations during similar geomagnetic conditions. Key Points: Maximum poleward shift (∼11°) of equatorial ionization anomaly crests was observed between ∼15°W and 5°W GlonReversed C‐shape Equatorial Plasma Bubbles (EPBs) extended to ∼±36° Mlat (∼40°N and ∼30°S Glat) with apex altitudes reaching ∼4,000 kmShear in EPBs zonal drifts is formulated as a function of magnetic apex heights based on their tilts [ABSTRACT FROM AUTHOR]

The processes in far scrape‐off layer (SOL) and the plasma interaction with the first‐wall (FW) elements may notably affect the tokamak discharge, since they define fuel and impurity recycling, material erosion and redeposition, wall surface heating, etc. For a long time, the far SOL description in most plasma edge transport codes was insufficient or absent at all, and so particle and heat fluxes onto the FW (except divertor plates) were out of consideration. Recently some codes, for example, SOLEDGE and SOLPS‐ITER are upgraded allowing for the extension of the computational grid up to real walls and for corresponding account of the vacuum vessel shape and all in‐vessel elements. The new release of SOLPS‐ITER (the version 3.2.0) required a development of a new code data structure and new approach to numerical approximation of fluid equations compatible with unstructured non‐orthogonal computational grid. Intensive testing of the new code in different conditions is still required. In the present contribution, such a testing is performed for the EAST disconnected double null (DDN) L‐mode discharge. For the first time, the SOLPS‐ITER 3.2.0 modeling results with drifts and currents turned on are presented, and a comparison to former SOLPS‐ITER version (3.0.8) is performed. The far SOL transport and its effects on the discharge performance are studied by comparing the computational results obtained on several meshes which differ by their width in equatorial midplane. A single null (SN) one (with mesh width limited by distance to the secondary separatrix) was examined versus two DDN meshes (one with actual and one with artificially extended targets to make mesh wider) and a true unstructured (the widest) mesh. The notable difference in results obtained on different meshes appears in those places where plasma density does not vanishes at the computational domain boundaries. For the cases on true unstructured (the widest) mesh, the particle and heat fluxes onto central column, limiters, far SOL part of targets, dome umbrella and other EAST far SOL in‐vessel structures are calculated for the first time by SOLPS‐ITER, allowing assessment of the plasma interaction with those surfaces. [ABSTRACT FROM AUTHOR]

Bottom currents play a major role in deep‐sea sedimentation, but their significance in the burial of organic carbon is poorly quantified at a global scale. Here we show that Holocene fluxes of organic carbon into the contourite drifts are high, with a global average of 0.09 g cm−2 Kyr−1. At individual drift sites, fluxes are commonly 1–2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zones. These high fluxes of organic carbon into the contourite drifts are due to high rates of sedimentation. Over the past 50 million years, sedimentation rates at the studied contourite drift sites have overall increased, coincident with decreasing atmospheric CO2 and a cooling global climate. Our work suggests that a ramp‐up of the bottom‐current carbon pump has accelerated removal of CO2 from the atmosphere and oceanic water, thus contributing to the overall global cooling after the Eocene Thermal Maximum. Plain Language Summary: Bottom currents play a major role in deep‐sea sedimentation, but their significance in the burial of organic carbon is poorly quantified at a global scale. Here we examine data from modern contourite drifts (large‐scale, alongslope‐trending bottom‐current deposits) across the globe and show modern fluxes of organic carbon into the drifts are high, with a global average of 0.09 g cm−2 Kyr−1. At individual drift sites, fluxes are commonly 1 to 2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zones. These high fluxes of organic carbon into the drifts are due to high rates of sedimentation in these deepwater environments, which are driven primarily by vigorous bottom currents—in other words, by a bottom‐current pump that is highly efficient at burying organic carbon. Our work suggests that a ramp‐up of the bottom‐current carbon pump, attributable to progressive intensification of global ocean circulation over the past 50 million years, has accelerated removal of CO2 from the atmosphere and oceanic water, thus contributing to the global cooling after the Eocene Thermal Maximum. Sedimentary records of past organic carbon fluxes in contourite drifts over geologic time could well prove useful in informing predictions of future climate. Key Points: Modern fluxes of organic carbon into the contourite drifts are high, with a global average of 0.09 g cm−2 Kyr−1The fluxes into the drifts are commonly 1–2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zonesOver the past 50 million years, the bottom‐current pump has accelerated removal of carbon from the oceanic water [ABSTRACT FROM AUTHOR]

In‐situ infrared spectroscopy is one of the most effective methods to study the surface species on solid catalysts. Still, it is sometimes difficult to identify the reactive intermediates because spectator species, the catalyst support, and experimental noise also contribute to the total spectra. In this study, we prepared three archetypical Ni/Al2O3 catalysts that showed significantly different catalytic activity and selectivity for CO2 hydrogenation, depending on the calcination and reduction temperature. After detailed characterization, we used a combination of Modulation Excitation‐Phase Sensitive Detection‐Diffuse Reflectance Infrared Fourier Transform Spectroscopy (ME‐PSD‐DRIFTS) and Steady State Isotopic Kinetic Analysis (SSITKA) to show that bicarbonates and formates are key reactive intermediates. Furthermore, we also observe carbonyls on the catalyst with the most metallic character and highest selectivity towards CH4. These results confirm that the hydrogenation of CO2 occurs in an associative and consecutive reaction pathway that is highly structure‐sensitive. In this way, we also demonstrate how the simultaneous collection of spectroscopic and kinetic data during modulated or transient experiments is a powerful tool for investigating solid catalysts under realistic operation conditions. [ABSTRACT FROM AUTHOR]

Observations show that equatorial ionospheric vertical drifts during solar minimum differ from the climatology between late afternoon and midnight. By analyzing WACCM‐X simulations, which reproduce this solar cycle dependence, we show that the interplay of the dominant migrating tides, their propagating and in situ forced components, and their solar cycle dependence impact the F‐region wind dynamo. In particular, the amplitude and phase of the propagating migrating semidiurnal tide (SW2) in the F‐region plays a key role. Under solar minimum conditions, the SW2 tide propagate to and beyond the F‐region in the winter hemisphere, and consequently its zonal wind amplitude in the F‐region is much stronger than that under solar maximum conditions. Furthermore, its phase shift leads to a strong eastward wind perturbation near local midnight. This in turn drives a F‐region dynamo with an equatorial upward drift between 18 and 1 hr local times. Plain Language Summary: The vertical ion motion in the equatorial ionosphere plays a key role in the space weather. Satellite observations found that such vertical motion during periods with low solar activity can be quite different from the known climatology, and the cause is not clear. Using a whole atmosphere general circulation model, WACCM‐X, we are able to reproduce the pattern of the vertical ion motion similar to that observed during low activity solar cycle periods. By analyzing the model results, we find that the relative significance of the different atmosphere tidal wave components and its variation with solar activity contribute to the solar dependence of the vertical ion motion. The propagating altitudes of tide with 12‐hr period, as well as where and when the tidal wind becomes large, are of particular importance. Key Points: Upward equatorial vertical ion drift near midnight under solar minimum conditions reproduced by WACCM‐XModulation of F‐region dynamo by propagating semidiurnal tide is much stronger during solar minimumTidal phase change in equatorial F‐region during solar minimum shifts upward drift toward midnight [ABSTRACT FROM AUTHOR]

During geomagnetic storms, the capabilities of current climate models in predicting ionospheric behavior are notably limited. A data assimilation tool, Estimating Model Parameters Reverse Engineering (EMPIRE), implements a Kalman filter to ingest electric density rate correcting the background electric potential and neutral wind. For the baseline setup, or case (1), EMPIRE ingests electron density global map output from the Ionospheric Data Assimilation 4‐Dimensional (IDA4D) algorithm. In this work, a new augmentation method is evaluated in which ion drift measurements are also assimilated into EMPIRE. The ion drift measurements used in the new augmentation method are obtained from Super Dual Auroral Radar Network (SuperDARN) sites in the mid‐to‐high latitude region of the northern hemisphere. Cases (2) and (3) are set up for evaluating the impacts from ingesting different types of observations: SuperDARN fit and grid data, respectively. Six independent data sources are used as validation data sets to compare outcomes with or without ingesting ion drifts. One is the vector ion velocities derived from the Millstone Hill Incoherent Scatter Radar (MHISR) and a second is the vertical drift from Arecibo site. The other four are SuperDARN ion velocity grid data from Saskatoon, Kapuskasing, Christmas Valley West, and Hokkaido East. Results show improvements in performance at mid‐latitudes by augmenting electron density rates with 3D spatially distributed line‐of‐sight ion drift measurements, with negligible improvements to low and high latitude estimations. The lack of improvement at high‐latitudes is attributed to the increase in EMPIRE ion drift error poleward of 60° magnetic. Plain Language Summary: Current climate models struggle to accurately predict changes in the ionosphere especially during geomagnetic storm time. A data assimilation system is implemented to improve the prediction of upper atmospheric drivers by incorporating measurement information of electron density in a global setting. This study introduces a new method that also includes ion drift measurements at the mid‐to‐high latitudes. Six independent data sets are compared to the results from the original and new experimental setups, and we investigate how the accuracy of our prediction is affected by the amount of pre‐processing of measurements before they are used. We find that ion motion measurements improve mid‐latitude ion drift estimations when more ion drift information is added to the DA system but no significant improvements at low and high latitudes. Key Points: We augment a data assimilation algorithm to ingest fit and gridded ion velocity data from the Super Dual Auroral Radar Network (SuperDARN)We compare the new augmentation results with the primary setup of only ingesting electron density ratesAssimilation of distributed line‐of‐sight fit drifts at high latitudes yields improvement at magnetic mid‐latitudes [ABSTRACT FROM AUTHOR]

Infrared spectroscopy (IR) is a widely used technique enabling to identify specific functional groups in the molecule of interest based on their characteristic vibrational modes or the presence of a specific adsorption site based on the characteristic vibrational mode of an adsorbed probe molecule. The interpretation of an IR spectrum is generally carried out within a fingerprint paradigm by comparing the observed spectral features with the features of known references or theoretical calculations. This work demonstrates a method for extracting quantitative structural information beyond this approach by application of machine learning (ML) algorithms. Taking palladium hydride formation as an example, Pd‐H pressure‐composition isotherms are reconstructed using IR data collected in situ in diffuse reflectance using CO molecule as a probe. To the best of the knowledge, this is the first example of the determination of continuous structural descriptors (such as interatomic distance and stoichiometric coefficient) from the fine structure of vibrational spectra, which opens new possibilities of using IR spectra for structural analysis. [ABSTRACT FROM AUTHOR]

We evaluate a decadal ozone profile record derived from the Suomi National Polar‐orbiting Partnership (SNPP) Ozone Mapping and Profiler Suite (OMPS) Limb Profiler (LP) satellite instrument. In 2023, the OMPS LP data were re‐processed with the new version 2.6 retrieval algorithm that combines measurements from the ultraviolet (UV) and visible (VIS) parts of the spectra. It employs the second order Tikhonov regularization to retrieve a single vertical ozone profile between 12.5 km (or cloud tops) and 57.5 km with a vertical resolution of about 1.9–2.5 km between 20 and 55 km. The algorithm uses radiances measured at six UV ozone‐sensitive wavelengths (295, 302, 306, 312, 317, and 322 nm) paired with 353 nm, and one VIS wavelength at 606 nm combined with 510 and 675 nm to form a triplet. Each wavelength pair or triplet is used over a limited range of tangent altitudes where the sensitivity to ozone change is strongest. A new aerosol correction scheme was implemented based on a gamma‐function particle size distribution. In addition, numerous calibration changes that affected ozone retrievals were applied to measured LP radiances, including updates in altitude registration, radiometric calibration, stray light, and spectral registration. The key version 2.6 enhancement is the improved stability of the LP ozone record confirmed by the reduction in relative drifts between LP ozone and correlative measurements, linked previously to a drift in the version 2.5 LP altitude registration. Plain Language Summary: The Montreal Protocol protects the Earth's ozone layer by regulating the production and usage of ozone‐depleting substances. As a result of this international treaty, we expect stratospheric ozone to increase over time. A series of OMPS Limb Profilers (LP) was designed to ensure continuous spaceborne capabilities for detecting changes in the stratospheric ozone distribution over several decades. The ozone record from the first OMPS LP on board the Suomi NPP mission spans more than 12 years, from April 2012 to the present. A statistically significant positive drift in the previous version 2.5 of LP ozone data, linked to a drift in the LP altitude registration, has compromised its fitness to accurately detect ozone trends. In this paper, we introduce the new version 2.6 OMPS LP ozone data set with improved stability. We found a substantial reduction in relative drifts between LP ozone and correlative measurements. Therefore, the version 2.6 LP ozone can be used with higher confidence for monitoring and quantifying stratospheric ozone recovery. Key Points: The ozone record from the first OMPS Limb Profiler that spans more than 12 years has been reprocessed with the new version 2.6 algorithmThe key v2.6 improvement is the reduction in relative drift that was linked previously to a drift in the v2.5 LP altitude registrationThe study demonstrates the importance of continuous improvements in calibration and retrieval to ensure accuracy and stability of LP ozone [ABSTRACT FROM AUTHOR]

Numerical forecasts of plasma convective instability in the postsunset equatorial ionosphere are made based on data from the Ionospheric Connections Explorer satellite (ICON) following the method outlined in a previous study. Data are selected from pairs of successive orbits. Data from the first orbit in the pair are used to initialize and force a numerical forecast simulation, and data from the second orbit are used to validate the results 104 min later. Data from the IVM plasma density and drifts instrument and the MIGHTI red‐line thermospheric winds instrument are used to force the forecast model. Thirteen (16) data set pairs from August (October), 2022, are considered. Forecasts produced one false negative in August and another false negative in October. Possible causes of forecast discrepancies are evaluated including the failure to initialize the numerical simulations with electron density profiles measured concurrently. Volume emission 135.6‐nm OI profiles from the Far Ultraviolet (FUV) instrument on ICON are considered in the evaluation. Plain Language Summary: Numerical forecasts of disruptions in the postsunset equatorial ionosphere are made from data from the Ionospheric Connections Explorer (ICON) satellite using the method outlined in a previous study. Data are selected from pairs of successive orbits–the first providing data for the numerical forecast model, and the second providing a means of validation. Specifically, measurements of vertical plasma drifts and horizontal wind profiles are used. Thirteen (16) orbital pairs from August (October) of 2022 are considered. The forecasts were accurate in the main but produced one false negative in August and another false negative in October. Reasons for the forecast discrepancies are analyzed including the failure to include electron density profile measurements in the forecast model initialization. Data from the Far Ultraviolet instrument on Icon are considered in the analysis. Key Points: ICON‐based numerical forecasts of plasma convective instability in the equatorial ionosphere extended through 2022Results mainly consistent with earlier ICON‐based forecastsICON FUV profiles used to investigate forecast discrepancies further [ABSTRACT FROM AUTHOR]

The synthesis of covalent organic frameworks (COFs) at bulk scale require robust, straightforward, and cost‐effective techniques. However, the traditional solvothermal synthetic methods of COFs suffer low scalability as well as requirement of sensitive reaction environment and multiday reaction time (2–10 days) which greatly restricts their practical application. Here, we report microwave assisted rapid and optimized synthesis of a donor‐acceptor (D−A) based highly crystalline COF, TzPm‐COF in second (10 sec) to minute (10 min) time scale. With increasing the reaction time from seconds to minutes crystallinity, porosity and morphological changes are observed for TzPm‐COF. Owing to visible range light absorption, suitable band alignment, and low exciton binding energy (Eb=64.6 meV), TzPm‐COF can efficaciously produce superoxide radical anion (O2.−) after activating molecular oxygen (O2) which eventually drives aerobic photooxidative amidation reaction with high recyclability. This photocatalytic approach works well with a variety of substituted aromatic aldehydes having electron‐withdrawing or donating groups and cyclic, acyclic, primary or secondary amines with moderate to high yield. Furthermore, catalytic mechanism was established by monitoring the real‐time reaction progress through in situ diffuse reflectance infrared Fourier transform spectroscopic (DRIFTS) study. [ABSTRACT FROM AUTHOR]

Fragipan horizons are common diagnostic subsurface features typically identified by their dense, brittle nature under field conditions. Fragipan horizons are often hypothesized to contain various silicate bonding agents, including phyllosilicates, amorphous aluminosilicates/silica, and silica sorbed to iron oxyhydroxides. However, the association of silica (Si) with other minerals in these horizons remains uncertain. To fill this knowledge gap, we sampled the prism and seam material of four loess‐derived fragipan horizons in western Kentucky. We characterized and compared the clay mineral composition of the prism and seam material using X‐ray diffraction (XRD), selective extractions, and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Fragipan prism and seam material exhibited a mixed clay mineralogy comprised of vermiculite, mixed layer minerals (hydroxyl‐interlayered vermiculite), illite, kaolinite, and quartz. We identified goethite in fragipan prisms in much greater quantities when compared to seam material, confirmed by both XRD and DRIFTS and corroborated by higher dithionite‐extractable iron in prisms. DRIFT spectra showed a peak near 3180 cm−1 assigned to OH‐stretching mode of goethite, which was prominent in prism materials. Goethite 110 XRD peak positions were negatively correlated to dithionite‐extractable aluminum (Al) and Si content of the prism material, which may suggest greater Si sorbed to the surfaces of Al‐substituted goethite. These results demonstrate the potential importance of Al‐substituted goethite in fragipan prisms and provide insight about possible associations with Si. Core Ideas: Aluminum (Al)‐substituted goethite was observed in fragipan prisms relative to seam material.Goethite 110 X‐ray diffraction peaks are correlated to dithionite‐extractable Al and silica (Si) content.Si sorbed to Al‐substituted goethites are potential important factors in fragipan prisms. [ABSTRACT FROM AUTHOR]

ABSTRACT The northern continental margin of the South China Sea (SCS) is an important component of deep‐water circulation, providing excellent conditions for studying bottom currents in a marginal sea. Seismic data were employed to discern the sedimentary patterns prevalent in the deep‐water continental slope sediments on the northern continental margin of the SCS, encompassing gravity flow, contourite and mixed depositional systems. The contourite depositional system includes various types of deposits (such as separated mounded drifts, patch or channel‐related drifts, deformed sheeted drifts, composite drifts, bottom current sediment waves, plastered contourite drifts) and various morphologic erosional features eroded by the bottom current (such as moats, non‐depositional surfaces, troughs and scarps). These contourite features are related to the continental slope's morphology and its sources. The Dongsha slope exhibits distinctive characteristics marked by intense bottom current erosion and deposition, featuring separated mounded drifts and deformed sheeted drifts along its lower slope. The lower slope of the Pearl River showcases a spectrum of bottom current‐induced features, including sediment wave fields, erosion fields and contourite drifts. The southern flank of the Shenhu slope is characterised by a bottom current erosion field, a non‐depositional surface, a sediment wave field and isolated mounded drifts. On the Yingqiong slope, the contourite drifts are limited to its southern flank where gravity flow action is absent, and the complex geomorphology interacts with the bottom current, forming a complex contourite depositional system. The results of this study serve as a foundational framework for further global research on bottom current circulation and hydrodynamics. [ABSTRACT FROM AUTHOR]

This paper presents a procedure for simplified collapse probability prediction of RC frame buildings when subjected to ground motion intensities commonly used in designing buildings. For this purpose, seismic collapse probability of a range of RC moment resisting frame buildings are assessed at the design basis earthquake (DBE) and the maximum considered earthquake (MCE) levels of seismic intensity by conducting more than a thousand nonlinear response history analyses (NRHA) using a suite of 40 seismic ground motion records. The 13 buildings included in the investigation have different heights (5–15 storeys) and footprints (3–6 bays), are designed to different target maximum inter‐storey drifts (within the code specified limit), and have critical members detailed to sustain different levels of confinement and anti‐buckling demands. The NRHA results consistently demonstrate that the design inter‐storey drift and the anti‐buckling detailing of longitudinal rebars in the critical frame members strongly influence the collapse probability of RC frame buildings. The results also show that while RC frame buildings designed to reach 2.5% (or less) inter‐storey drifts and detailed for ductile seismic performance can successfully avoid collapse at DBE, avoidance of collapse at DBE cannot be guaranteed if RC frames are designed to reach a target drift of more than 2% and not detailed for full ductility. At MCE, collapse probability is found to consistently exceed 10% unless the building is designed to incur no more than 1% plastic drift and the frame members have ductile detailing. Based on the NRHA results of the 13 case study buildings, easy‐to‐use equations relating their seismic collapse probability at MCE with the design drift and a quantifiable measure of ductile detailing are generated and validated by comparing with the collapse probability obtained by NRHA of an independent RC frame building. The proposed equations provide a rapid, yet reasonably reliable tool for performance‐based seismic design of RC frame buildings, and enable designers to estimate seismic collapse probability of RC frame buildings without having to conduct cumbersome NRHA. [ABSTRACT FROM AUTHOR]

In this study, the evolutional features and underlying driving mechanisms of the postmidnight‐to‐dawn equatorial plasma bubble (EPB) irregularities during the weak geomagnetic activity period on 13 November 2015 were investigated based on the multiple satellite and ground‐based observations. By using the coherent scatter radar operating at very high frequency at Fuke (19.5°N, 109.1°E, dip latitude 14.4°N), China, it was found that the freshly developed field‐aligned irregularities (FAIs) occurred within the radar's field of view around ∼04:37 LT and sustained for more than 40 min. The remarkable EPB‐related density and total electron content (TEC) depletions measured by the satellite and GNSS receivers were also observed, which indicates the persistence of EPB irregularities until ∼06 LT. The significant elevation of bottomside F‐layer's virtual height obtained by the Digisonde at Fuke as well as the upward vertical F‐layer plasma drifts derived from a nearby Digisonde at Sanya (18.4°N, 109.6°E, dip latitude 13.1°N) both imply the existence of strong eastward perturbation electric fields after local midnight. These findings suggest that the collective effects of eastward overshielding penetration electric field (PEF) resulted from the substorm onset and rapid northward turning of the interplanetary magnetic field (IMF) Bz, surpassed the role of westward undershielding prompt penetration electric field (PPEF) induced by the southward turning of IMF Bz. Thus, the former predominated in modulating the equatorial/low‐latitude zonal electric fields and raised the F‐layer considerably, which consequently boosted the growth of R‐T instability and created the favorable conditions for the postmidnight‐to‐dawn EPBs development. Key Points: Freshly developed field‐aligned irregularities last for 40 min within the radar's field‐of‐view and the equatorial plasma bubble (EPBs)‐related density depletions show the EPBs sustaining until ∼06 LTThe competition process among different perturbation electric fields for triggering the postmidnight‐to‐dawn EPB irregularities is examinedThe eastward overshielding penetration electric field resulted from substorm onset and interplanetary magnetic field Bz northward turning provide favorable conditions for EPB development [ABSTRACT FROM AUTHOR]

Joule heating is a major energy sink in the solar wind‐magnetosphere‐ionosphere system and modeling it is key to understanding the impact of space weather on the neutral atmosphere. Ion drifts and neutral wind velocities are key parameters when modeling Joule heating, however there is limited validation of the modeled ion and neutral velocities at mid‐latitudes. We use the Blackstone Super Dual Auroral Radar Network radar and the Michigan North American Thermosphere Ionosphere Observing Network Fabry‐Perot interferometer to obtain the local nightside ion and neutral velocities at ∼40° geographic latitude during the nighttime of 16 July 2014. Despite being a geomagnetically quiet period, we observe significant sub‐auroral ion flows in excess of 200 ms−1. We calculate an enhancement to the local Joule heating rate due to these ion flows and find that the neutrals impart a significant increase or decrease to the total Joule heating rate of >75% depending on their direction. We compare our observations to outputs from the Thermosphere Ionosphere Electrodynamic General Circulation Model (TIEGCM). At such a low geomagnetic activity however, TIEGCM was not able to model significant sub‐auroral ion flows and any resulting Joule heating enhancements equivalent to our observations. We found that the neutral winds were the primary contributor to the Joule heating rates modeled by TIEGCM rather than the ions as suggested by our observations. Plain Language Summary: Charged particle motion in Earth's upper atmosphere creates heating called Joule heating which causes the atmosphere to expand, increasing drag for objects and satellites. Charged particle velocities are typically greater at high‐latitudes than mid and lower latitudes. At mid and lower latitudes, Earth's neutral atmosphere can move faster than the charged particles and produce Joule heating. We can use ground based instruments to observe this particle motion and estimate the Joule heating. Physical models can estimate the Joule heating for different space weather conditions. These physical models show good estimations of the high‐latitude Joule heating compared to estimations, however there is limited validation of their performance at mid‐latitudes. We use ground based instruments to estimate the Joule heating over mid‐latitude North America for one night and compare to outputs from a physics model called the Thermosphere Ionosphere Electrodynamic General Circulation Model (TIEGCM). Despite quiet driving conditions, we observe significant charged particle motion driving enhanced Joule heating rates. We find that TIEGCM was unable to model these strong charged particle motions nor any Joule heating enhancements equivalent to our observations. While the observed heating resulted from faster charged particle motion, the Joule heating rates in TIEGCM were produced by the greater neutral winds instead of ion drifts. Key Points: Observations from a Fabry‐Perot interferometer and Super Dual Auroral Radar Network radar were used to estimate quiet‐time mid‐latitude Joule heating rates during 16 July 2014The neutral winds accounted for between 24% and 43% of the total observed local Joule heating ratesJoule heating enhancements were observed approximately 8 times higher than modeled by the Thermosphere Ionosphere Electrodynamic General Circulation Model due to excitations in sub‐auroral ion motion [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction is considered as a promising strategy for CO2 utilization and producing renewable energy, however, it remains challenge in the improvement of photocatalytic performance for wide‐band‐gap photocatalyst with controllable product selectivity. Herein, the sulfur‐doped In(OH)3 (In(OH)xSy‐z) nanocubes are developed for selective photocatalytic reduction of CO2 to CH4 under simulated light irradiation. The CH4 yield of the optimal In(OH)xSy‐1.0 can be enhanced up to 39 times and the CH4 selectivity can be regulated as high as 80.75% compared to that of pristine In(OH)3. The substitution of sulfur atoms for hydroxyl groups in In(OH)3 enhances the visible light absorption capability, and further improves the hydrophilicity behavior, which promotes the H2O dissociation into protons (H*) and accelerates the dynamic proton‐feeding CO2 hydrogenation. In situ DRIFTs and DFT calculation confirm that the non‐metal sulfur sites significantly weaken the over‐potential of the H2O oxidation and prevent the formation of ·OH radicals, enabling the stabilization of *CHO intermediates and thus facilitating CH4 production. This work highlights the promotion effect of the non‐metal doping engineering on wide‐band‐gap photocatalysts for tailoring the product selectivity in photocatalytic CO2 reduction. [ABSTRACT FROM AUTHOR]

Observations using Arecibo Observatory's highly sensitive Incoherent Scattering Radar (AO‐ISR) show ionospheric descending layers from as high as ∼400 km, much higher than earlier studies, with continuity down to 90 km. The AO‐ISR was operated to observe the ion‐line and plasma‐line with coded‐long‐pulse for high temporal and spatial resolution of 35/10 s and 300 m, respectively, during 01–06 February 2019. We found multiple layering structures descending from 400 to 90 km in all these six days. These layers are traditionally called intermediate descending layers (IDLs) (>130 km and below F‐peak), upper semi‐diurnal daytime and nighttime layers (110–130 km), and lower diurnal layers (<110 km). We have denoted the new daytime descending layers above the hmF2 as top‐side descending layers (TDLs). All these layers are collectively named ionospheric descending layers (IonDLs) since all of them are connected with some discontinuity at the F1‐peak (i.e., 170 km), except for the daytime lower‐diurnal layer. The most pronounced IonDLs occur in the twilight times. IonDLs mainly occur in shear zones of the vertical ion drifts and are favored by downward ion drifts, and their descent speeds increase with increasing altitude. The estimated phase velocities of the waves in the F‐region are comparable with the descending speed of the IonDLs. Furthermore, IonDLs/IDLs occur with and without spread‐F events but intensified spread‐F events raise their beginning altitude. The TDLs and IDLs are driven by gravity waves with periods of 1.5–4 hr. Key Points: We found ionospheric descending layers (IonDLs) that start near ∼400 km and descend down to ∼90 kmWe observe traditional intermediate descending layers (IDLs) starting from ∼300–350 km (below ∼170 km) during the nighttime (daytime)The daytime top‐side descending layers (from 400 km) and IDLs are governed by the waves with periods of ∼1.5–4 hr [ABSTRACT FROM AUTHOR]

Last decade demonstrate the massive growth in organizational data which keeps on increasing multi‐fold as millions of records get updated every second. Handling such vast and continuous data is challenging which further opens up many research areas. The continuously flowing data from various sources and in real‐time is termed as streaming data. While deriving valuable statistics from data streams, the variation that occurs in data distribution is called concept drift. These drifts play a significant role in a variety of disciplines, including data mining, machine learning, ubiquitous knowledge discovery, quantitative decision theory, and so forth. As a result, a substantial amount of research is carried out for studying methodologies and approaches for dealing with drifts. However, the available material is scattered and lacks guidelines for selecting an effective technique for a particular application. The primary novel objective of this survey is to present an understanding of concept drift challenges and allied studies. Further, it assists researchers from diverse domains to accommodate detection and adaptation algorithms for concept drifts in their applications. Overall, this study aims to contribute to deeper insights into the classification of various types of drifts and methods for detection and adaptation along with their key features and limitations. Furthermore, this study also highlights performance metrics used to evaluate the concept drift detection methods for streaming data. This paper presents the future research scope by highlighting gaps in the existing literature for the development of techniques to handle concept drifts. This article is categorized under:Algorithmic Development > Ensemble MethodsApplication Areas > Data Mining Software ToolsFundamental Concepts of Data and Knowledge > Big Data Mining [ABSTRACT FROM AUTHOR]

Purpose: To enable a real‐time applicator guidance for brachytherapy, we used for the first time infra‐red tracking cameras (OptiTrack, USA) integrated into a mobile cone‐beam computed tomography (CBCT) scanner (medPhoton, Austria). We provide the first description of this prototype and its performance evaluation. Methods: We performed assessments of camera calibration and camera‐CBCT registration using a geometric calibration phantom. For this purpose, we first evaluated the effects of intrinsic parameters such as camera temperature or gantry rotations on the tracked marker positions. Afterward, calibrations with various settings (sample number, field of view coverage, calibration directions, calibration distances, and lighting conditions) were performed to identify the requirements for achieving maximum tracking accuracy based on an in‐house phantom. The corresponding effects on camera‐CBCT registration were determined as well by comparing tracked marker positions to the positions determined via CBCT. Long‐term stability was assessed by comparing tracking and a ground‐truth on a weekly basis for 6 weeks. Results: Robust tracking with positional drifts of 0.02 ± 0.01 mm was feasible using the system after a warm‐up period of 90 min. However, gantry rotations affected the tracking and led to inaccuracies of up to 0.70 mm. We identified that 4000 samples and full coverage were required to ensure a robust determination of marker positions and camera‐CBCT registration with geometric deviations of 0.18 ± 0.03 mm and 0.42 ± 0.07 mm, respectively. Long‐term stability showed deviations of more than two standard deviations from the initial calibration after 3 weeks. Conclusion: We implemented for the first time a standalone combined camera‐CBCT system for tracking in brachytherapy. The system showed high potential for establishing corresponding workflows. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to study and compare the structural reliability of steel moment resisting frames (SMRFs) and steel frames with X‐bracing systems considering the performance‐based seismic design (PBSD) philosophy. In this sense, to accomplish such a study, nonlinear response history analysis is implemented. The buildings under consideration are designed to be located in Culiacan, Mexico. The results are presented in terms of overall displacements, rotations of connections, and interstory drifts, for three performance levels: (1) immediate occupancy, (2) life safety, and (3) collapse prevention, respectively. For each performance level, 11 ground motions were selected to study the response of the structures. Such responses were extracted by using the SAP2000 commercial software to perform structural analysis. It was demonstrated that the steel frame with X‐bracing systems developed a better seismic performance than SMRFs for all three variables under consideration. In addition, it was found that a reduction up to 70% in overall displacements and interstory drifts can be achieved when X‐bracing systems are used in steel structures. The risk of the structures was extracted in terms of reliability index and probability of failure considering probability density functions of interstory drifts. It was demonstrated that reliability index increased for structures with X‐bracing systems in comparison with SMRFs. Finally, in terms of costs, steel structures with X‐bracing systems are more expensive than SMRFs. However, its use is justified because serviceability conditions as overall displacement and interstory drift are considerably reduced. [ABSTRACT FROM AUTHOR]

Background: Misalignment or double‐contouring artifacts can appear in high‐resolution 3D cone beam computed tomography (CBCT) images, potentially indicating geometric accuracy issues in the projection data. Such artifacts may go unnoticed in low‐resolution images and could be associated with changes in the focal spot (FS) position. Purpose: High‐resolution 3D‐CBCT imaging by a mobile imaging device with a large gantry clearance offers more versatility for clinical workflows in image‐guided brachytherapy (IGBT), intraoperative radiation therapy (IORT), and spinal, as well as maxillofacial surgery. However, misalignment or double‐contouring artifacts hinder workflow advancements in these domains. This paper introduces intrinsic calibration and geometrical correction methods as extensions to a well‐established technique for addressing geometrical deviations resulting from factors such as gravity or mechanical inconsistencies. These extensions cover shifts and drifts of the FS depending on FS size selection, temperature, tube current, and tube potential. The proposed methods effectively mitigate artifacts in high‐resolution CBCT images stemming from geometrical inaccuracies in projection data, without requiring additional equipment like a pinhole device. Methods: Geometrical offsets and drifts of the x‐ray tube FS were characterized on a mobile multi‐purpose imaging system, the ImagingRing‐m. A pinhole‐like experiment was simulated by adjusting the movable collimation unit to a small rectangular aperture within the FS size range. The influence of filament selection, that is, FS size, temperature, the relatively low tube currents, as well as tube potential settings have been studied on two different monobloc types sharing the same x‐ray tube insert. The Catphan 504 and an Alderson head phantom were used to assess resulting image artifacts. Results: Switching the FS size to one different from what was used for geometrical (gravitation, mechanical variations) calibration induced the most notable position changes of the x‐ray FS, resulting in double‐contouring artifacts and blurring of high‐resolution 3D‐CBCT images. Incorporating these shifts into a geometrical correction method effectively minimized these artifacts. Thermal drifts exhibited the second largest geometrical changes, comparable to FS size shifts across the thermal operating conditions of the x‐ray system. The proposed thermal drift compensation markedly reduced thermal drift effects. Tube current and potential had little impact within the range of available tube currents, eliminating the need for compensation in current applications. Conclusions: Augmenting the geometrical calibration pipeline with proposed FS drift compensations yielded significant enhancements in image quality for high‐resolution reconstructions. While compensation for thermal effects posed challenges, it proved achievable. The roles of tube current and potential were found to be negligible. [ABSTRACT FROM AUTHOR]

Using an in–house developed Quasi Two–Dimensional (QTD) physics–based ionospheric model, the impact of E × B drift velocity on the vertical distribution of the electron density over the equatorial latitude has been investigated. The vertical drift measurements from (a) drift analysis software of Digisonde (b) derived from Digisonde ionograms (c) calculated from the Scherliess–Fejer (SF) model, and (d) obtained from the magnetometer ΔH measurements have been used in this study. Four quiet days in a low solar activity year, representing four seasons of the year 2010, have been chosen for the study. The model–derived electron density profiles using the vertical drifts from all four methods matched well with the Digisonde observation below ∼150 km at all the Local Times (LTs) for all 4 days. However, since the Digisonde–derived drifts were very low, centered mostly around zero, it led to the overestimation/underestimation of the F–region peak plasma density (nmF2)/height (hmF2). The model simulated electron density profiles using the SF model, and ΔH derived vertical drifts showed good agreement with the observation up to an altitude of ∼350 km. The study showed that vertical drift is a factor that controls the nmF2 trough around noon over the equatorial latitude. It is seen that plasma diffusion occurs only beyond an altitude of 350 km, while the range of altitudes between 320 and 350 km acts as the "diffusion threshold height." This finding has significant implications for understanding plasma dynamics in the equatorial ionosphere. Plain Language Summary: The present study employed a quasi–two–dimensional theoretical ionospheric model to investigate the impact of vertical drift on the electron density distribution over the equatorial ionosphere. Utilizing vertical drift values derived from Digisonde, Scherliess–Fejer (SF) model calculations, and magnetometer readings, the model was simulated for four distinct days of 2010 representing the four seasons of the year. The electron density profiles generated using all four techniques exhibited a close match to the observed values for all 4 days. However, when very low Digisonde–derived drifts were employed, an overestimation of the F–region density and an underestimation of peak F–region plasma density heights were observed. The study demonstrated that the model–simulated electron density profiles, generated using the SF model and magnetometer–derived vertical drifts, exhibited excellent agreement with the observed profiles at altitudes up to approximately 350 km. Similar variations of the calculated and observed nmF2 values led to the conclusion that vertical drift is a crucial factor in controlling the equatorial noon–time nmF2 trough. Furthermore, the study revealed that plasma diffusion occurred only beyond an altitude of 350 km as the altitude range of 320–350 km acts like a "diffusion threshold height." Key Points: This paper studies the impact of vertical drift on the vertical distribution of the electron densityThe plasma vertical drift plays an important role in the noon time nmF2 troughThe altitude range 320–350 km can be called as the plasma "diffusion threshold height" [ABSTRACT FROM AUTHOR]

Side‐scan sonar is a lightweight acoustic sensor that is frequently deployed on autonomous underwater vehicles (AUVs) to provide high‐resolution seafloor images. However, using side‐scan images to perform simultaneous localization and mapping (SLAM) remains a challenge when there is a lack of 3D bathymetric information and discriminant features in the side‐scan images. To tackle this, the authors propose a feature‐based SLAM framework using side‐scan sonar, which is able to automatically detect and robustly match keypoints between paired side‐scan images. The authors then use the detected correspondences as constraints to optimise the AUV pose trajectory. The proposed method is evaluated on real data collected by a Hugin AUV, using as a ground truth reference both manually‐annotated keypoints and a 3D bathymetry mesh from multibeam echosounder (MBES). Experimental results demonstrate that this approach is able to reduce drifts from the dead‐reckoning system. The framework is made publicly available for the benefit of the community. [ABSTRACT FROM AUTHOR]

Two ∼2‐week Ultra‐Fast Kelvin Wave (UFKW) events centered on days 158(203) during 2021 are investigated using winds, temperatures, plasma drifts and electron densities (Ne) measured by the Ionospheric CONnections (ICON) mission. Eastward‐propagating longitudinal wave‐1 (s = −1) structures with periods 2.5–4.0d, thought to mainly reflect Ultra‐Fast Kelvin waves (UFKWs), reveal ±45 ms−1 zonal winds (U) at 100 km for both events. Height‐latitude structures of the 3.0(3.5)d‐period UFKWs are obtained for the first time for both temperature (T, 94–120 km) and U (94–280 km) between 12°S and 39°N latitude. Maximum values of 36(29) ms−1 for U and 12(15)K for T occur at 102(106) km altitude and within ±3° latitude. The U‐T peak height displacement remains unexplained. Vertical wavelengths are in the range 36–43 km for both U and T during both events. Concurrent with the E‐region dynamo winds, topside (580 km) F‐region field‐aligned (±20–40 ms−1), meridional (±5–10 ms−1) and vertical (±5–10 ms−1) drift and Ne (±20–40%) 2.5–4.0d s = −1 variations are also measured. These key elements of atmosphere‐ionosphere (A‐I) coupling, contemporaneously measured for the first time, are relevant to testing the internal consistency of A‐I models. The mean wind propagation environment of the UFKWs is also quantified, showing no appreciable effects on the UFKW structures, consistent with modeling and theory. Plain Language Summary: Atmospheric Ultra‐Fast Kelvin waves (UFKWs) are eastward‐ and vertically propagating oscillations with periods less than 1 week that are centered on the equator and confined to low latitudes. They are part of a whole spectrum of waves forced by the spatial‐temporal variability of the heat of condensation ("latent heating") that is released when rising moist air forms rain droplets, mainly in the tropics. At high altitudes UFKW reach large amplitudes due to the decrease in ambient density with height. Their growth is curtailed by the viscosity of the atmosphere near 102 km altitude where they reach maximum amplitudes. Here they interact with ionized particles (the ionosphere) and generate electric fields that ultimately drive ionospheric variability at higher altitudes (>200 km), thus presenting an element of "space weather" to navigation and communications systems. In this paper, UFKWs measured in connection with the ICON mission are used to reveal, for the first time, the height and latitudinal structures of temperatures and winds associated with UFKWs in this dissipative regime, and their corresponding effect on the ionosphere. These results can thus serve to assess the internal consistency of models that seek to simulate atmosphere‐ionosphere coupling and related space weather effects induced by the wave spectrum excited in the lower atmosphere. Key Points: First coincident UFKW winds and temperature structures covering 94‐120 km,12°S‐39°N latitude are reportedFirst UFKW wind profiles in the 100‐280 km altitude dissipative regime are reportedFirst contemporaneous measurements of ionosphere response and driving UFKW E‐region dynamo winds are reported [ABSTRACT FROM AUTHOR]

A variety of innovative structural solutions have been recently introduced to mitigate damage and expedite the repair of buildings subjected to extreme seismic events, hence contributing to the urgent need for resilient societies. In this context, the present study experimentally and numerically investigates an innovative reinforced concrete (RC) shear wall (SW) structure with replaceable coupling beams (CBs) equipped with hybrid devices. These hybrid devices couple metallic and viscoelastic dampers and aim at satisfying multiple lateral load performances effectively. To assess the seismic performance of the proposed coupled SWsystem and verify the design principle, comparative shaking table tests were performed on two 1/4-scale seven-story SW structure specimens, including a conventional RC coupled SW and the proposed coupled SW with hybrid devices. The tests results indicate the improved performance of the proposed compared with the conventional system in terms of: (1) reduced interstory drifts and story accelerations demand under awide range of seismic intensities, (2) concentrated damage in the hybrid device and minimal damage to the other components contributing to the reparability of the structure. Furthermore, 3D finite element models for the shaking table test specimens were established in OpenSees and validated against experimental response. Successively, a numerical parametric study was conducted by performing non-linear response history analyses under a set of 22 ground motions to investigate the influence of different design configurations of the hybrid device on the peak interstory drifts and peak story accelerations. [ABSTRACT FROM AUTHOR]

The Low lAtitude long Range Ionospheric raDar (LARID), which consists of two high frequency (HF) radars looking toward the east and west of Hainan Island, respectively, has been developed and installed at Dongfang (19.2°N, 108.8°E, dip lat. 13.8°N), China. This paper describes the system design of LARID and its first observational results of equatorial plasma bubble (EPB) irregularities. The antenna array of LARID is composed of a west‐looking array and an east‐looking array. Each array consists of 20 log‐periodic antennas for transmission and reception and 4 log‐periodic antennas for interferometry, and has a beam steering capability in the azimuth angles of ±24° due the boresight pointing east (or west). Observational results show that the LARID is capable of detecting backscatter echoes from EPB irregularities and the ground, with a distance of 4,000 km or more away from Hainan Island. Multiple EPB structures were continuously observed on 17 April 2023, with eastward drifts ranging between 70 and 130 m/s. Based on ray tracing simulations, the backscatter echoes of EPB irregularities were due to the 0.5‐hop and 1.5‐hop propagation modes. The distances between the successive EPB structures were estimated ranging between 500 and 900 km in longitude. The LARID observations, together with other instruments in the East and Southeast Asian sector, provided a clear picture of longitudinal variation of EPBs in 90–125°E. It is expected that the LARID will provide an important tool to study the generation and evolution of EPBs and their short‐term prediction in East and Southeast Asia. Key Points: A Low lAtitude long Range Ionospheric raDar (LARID) operating at 8–22 MHz has been developed and installed at Hainan Island, ChinaFirst long‐range observations of equatorial plasma bubble (EPB) irregularities and their zonal drifts by the LARID were presentedThe LARID is expected to play an important role in the study of EPB and its short‐term forecasting in East and Southeast Asia [ABSTRACT FROM AUTHOR]

Space‐weather conditions can often have a detrimental impact on satellite communications and limited experimental data has made it challenging to understand the complex processes that occur in the upper atmosphere. To overcome this challenge, we utilized a coordinated multi‐instrumental dataset consisting of GNSS airglow remote sensing, ionosonde, magnetometer, and in‐situ satellite data to investigate plasma depletions. We present a case study focused on the geomagnetic storm that occurred on 27 February 2014. During the storm, GNSS positioning errors exceeded undisturbed levels by at least 2 times, and ionospheric corrections reached amplitudes of up to ±20 m at the Rabat station. We identified 3 large depletions that were most likely generated by sudden vertical ionospheric drifts that began at approximately 17:00 UTC at sunset in Morocco and the southern regions of Spain. These drifts reached ∼500 m/s and lasted until 22:00 UTC. The observed depletions propagated to the northeast, as seen through ionosonde echoes and ground‐based airglow images. Satellite limb‐images revealed an ionospheric uplift of about 100 km due to the storm, consistent with ionosondes in Spain. The observed local anomalies may be influenced by variations in equatorial electric current flows, which are correlated with fluctuations in ground‐based magnetometer data. These variations are likely a result of the effects of the inner radiation belt on the development of plasma bubbles in the African longitude sector. Sudden enhancements in upward E × B drift caused ionospheric uplift to higher altitudes, enhancing the "fountain effect" and shifting the Equatorial Ionospheric Anomaly crests to higher latitudes. Key Points: Large plasma depletions at midlatitude ionosphere during February 2014 storm were studied using coordinated multi‐instrumental datasetIonospheric corrections reached amplitudes of up to ±20 m at GNSS sensors in MoroccoPlasma depletions propagate in the North‐East direction, and storm‐time enhanced E × B drift caused an uplift of the ionosphere of 100 km [ABSTRACT FROM AUTHOR]

The Loop Current is a key component of global circulation via the northward transport of warm, salty water, and an important influence on Gulf of Mexico hydrography. Understanding how the Loop Current will respond to ongoing anthropogenic warming is critically important, but the history of the Loop Current is poorly known. Here, we present the results of a high resolution (3–8 m) multichannel seismic survey of pelagic carbonate sediment drifts on the eastern Campeche Bank associated with the Loop Current. We identify three seismic megasequences: Megasequence A is a Lower Cretaceous carbonate platform, Megasequence B comprises Cretaceous to lower Cenozoic pelagic carbonates with weak/no contour current flow, and Megasequence C comprises a series of large (100s of m thick) contourite drifts representing the inception and history of the Loop Current. The base of the contourites is marked by a regionally mappable unconformity eroding underling strata, sometimes incising hundreds of meters. The drifts contain a succession of sequence sets separated from each other by regional unconformities and comprising plastered drifts and massive mounded drifts, which characterize modern deposition with active moats on the seafloor. A lack of sediment cores in the study area precludes age determination of these drifts, except for the youngest (Late Pleistocene). Comparison to legacy seismic lines across Deep Sea Drilling Project Site 95, outside our study area, implies that the base of Megasequence C is Oligocene in age, and that the Loop Current developed during the global reorganization of ocean circulation around the Eocene‐Oligocene Transition. Plain Language Summary: The Loop Current flows into the Gulf of Mexico from the Caribbean through the Yucatán Strait and exits to the Atlantic Ocean through the Straits of Florida. It is part of a series of currents that carry warm, salty water to the far North Atlantic, where it cools and sinks, and becomes a critical part of global ocean circulation. The Loop Current is also important for Gulf of Mexico climate, as it sometimes spins off warm eddies which drift west, disrupting fisheries and providing a warm water fuel source for hurricanes. Because of its role in global and regional climate, it is important to understand how the Loop Current will respond to ongoing climate change, and an essential part of that effort is seeing how it has responded to past climate changes. Here, we report the results of a seismic survey of sediment drifts on the eastern Campeche Bank which we believe records the initiation and history of the Loop Current. A lack of sediment cores in this area makes it hard to put age constraints on our observations, so we evaluate several plausible hypotheses about when the Loop Current first formed and what that means for the current's future. Key Points: High resolution multichannel seismic data reveal the evolution of contourite drifts associated with the Loop CurrentContourite deposition began in the Cenozoic, and overlies Cenozoic and Cretaceous pelagic sediments with little evidence of bottom currentsComparison of seismic facies with those present at nearby DSDP Site 95 suggest the Loop Current began in the early Oligocene [ABSTRACT FROM AUTHOR]

Aim: To assess temporal trends of chronic kidney disease (CKD) attributable to type 2 diabetes (T2D) globally and in five sociodemographic index (SDI) regions. Materials and Methods: We extracted the population data and CKD burden attributable to T2D from the Global Burden of Disease Study 2019. We evaluated the trends of disability‐adjusted life years (DALYs), mortality, prevalence and incidence through age‐period‐cohort modelling, and calculated net drifts (overall annual percentage changes), local drifts (annual percentage changes in each age group), longitudinal age curves (fitted longitudinal age‐specific rates), period relative risks (RRs) and cohort RRs. Results: From 1990 to 2019, the global burden of CKD attributable to T2D showed increasing trends in general. The burden of CKD attributable to T2D was highest in the middle SDI region and lowest in the low SDI region. Age effects increased with age, and peaked at the ages of 75‐79 and 80‐84 years for incidence and prevalence, respectively. Period RRs in the burden of CKD attributable to T2D increased, with the high SDI being the most remarkable in DALYs and mortality, and the middle SDI being the most notable in incidence. Cohort RRs showed unfavourable trends in incidence and prevalence among recent cohorts. Conclusions: After a lengthy period of multi‐initiative diabetes management, the high‐middle SDI region exhibited improvement. However, unresolved issues and improvement gaps were still remarkable. Future efforts to reduce the burden of CKD attributable to T2D in the population should prioritize addressing the unfavourable patterns identified. [ABSTRACT FROM AUTHOR]

We investigate the generation of low latitude daytime E region field‐aligned irregularities (FAIs) and focus on whether the FAIs are exclusively linked with sporadic E (Es) and whether the FAIs are driven by wind‐driven gradient‐drift instability (GDI). For this investigation, we use observations of FAIs made by the 30 MHz Gadanki Ionospheric Radar Interferometer (GIRI) and Es made by the DPS‐4D digital ionosonde, both collocated at Gadanki. We have also examined simultaneous GIRI and Ionospheric Connection Explorer wind observations to substantiate our results. Results show that daytime E region FAIs are closely linked with Es activity and FAIs are not formed when Es is absent. FAIs are formed when blanketing frequency of Es (fbEs) exceeds frequency of the E layer. Both signal‐to‐noise ratio (SNR) and spectral width of the FAIs echoes display close relationship with top frequency of Es (ftEs). Further, SNR and spectral width of the FAIs echoes display a near‐linear relationship with minimum deviation when Es activity is moderate and show dispersion from near‐linear relationship when Es activity is strong. Zonal drift of the FAIs are predominantly eastward displaying both positive and negative vertical shear. Results also show that Es activity in terms of fbEs and ftEs is found to be closely related to the vertical shear in the zonal drift of the FAIs. Considering the height region of FAIs being highly collisional, we argue that zonal drifts are dominated by zonal wind and vertical shear in the zonal neutral wind is responsible for the formation/maintenance of Es layer and the eastward neutral wind is primarily responsible for the generation of the FAIs through the GDI. Plain Language Summary: Electron density irregularities are increasingly becoming relevant for precision in high frequency communication including the Over‐The‐Horizon radar applications, Synthetic Aperture Radar applications, and GPS‐RO based atmospheric measurements. The origin of electron density irregularities at low latitudes a few degrees away from the magnetic equator, where the background electric fields and currents are much weaker than those of the equatorial electrojet and the sporadic E (Es) layers are not as strong as those of midlatitudes, is not fully understood. In this work, we analyze simultaneous observations of daytime field‐aligned irregularities (FAIs) made by the 30 MHz Gadanki Ionospheric Radar Interferometer (GIRI) and Es made by the DPS‐4D digital ionosonde, both collocated at Gadanki, to investigate the roles of Es and neutral wind and/or electric field on their generation. We have also examined simultaneous GIRI and Ionospheric Connection Explorer wind observations. Results show that the daytime E region FAIs are directly related to Es layer and FAIs do not occur when Es is absent. Results also show that vertical shear in the zonal neutral wind is responsible for the formation/maintenance of Es layer and the eastward neutral wind is primarily responsible for the generation of the FAIs through the gradient drift instability. Key Points: Daytime low latitude E region field‐aligned irregularities (FAIs) are exclusively linked with sporadic E (Es)FAIs are linked with eastward neutral wind and their drifts are predominantly eastwardEs parameters are closely related to the vertical shear in the zonal drift of the FAIs [ABSTRACT FROM AUTHOR]

In divertor plasmas, atomic processes play a significant role in reducing the divertor heat load. In particular, the elastic scattering between ions and neutral particles can be characterized as a large‐angle scattering; this is in contrast with Coulomb scattering, which is dominated by small‐angle scattering. In a large‐angle scattering, a large fraction of the ion energy is transferred to the neutral particle, and the particle flight direction can be changed significantly. This process can generate additional particle transport perpendicular to magnetic field lines and affect plasma density profile in neutral‐rich divertor regions. However, in most edge plasma simulation codes, the elastic scattering with neutral particles is not taken into account in the direction perpendicular to the magnetic field lines. In this study, we performed a 2D orbital calculation without other drifts such as diamagnetic and E × B drifts to assess the effect of the elastic scattering on the density profile. The peak density is found to be decreased by 11.1 (6.3)% compared with the model that ignores the transport due to the elastic scattering, even at 3.0 (5.0) T magnetic field similar to that of the JT‐60SA (JA DEMO reactor) class. In addition, the ion transport can be expressed as a diffusion model by integrating the differential cross section over the large‐angle scattering range π/2−π$$ \pi /2-\pi $$. The proposed method may be easily introduced into any integrated codes to consider the elastic scattering. [ABSTRACT FROM AUTHOR]

We present a unified approach to subauroral arcs within intense subauroral ion drifts (SAID), which explains the observed transition of a precursor Stable Auroral Red (SAR) arc into Strong Thermal Emission Velocity Enhancement (STEVE). This approach is based on the short‐circuiting concept of fasttime SAID as an integral part of a magnetospheric voltage generator between the innermost boundaries of the freshly injected plasma sheet electrons and ring current ions. Here, enhanced plasma turbulence rapidly heats the bulk plasma and accelerates suprathermal non‐Maxwellian "tails." Heat and suprathermal electron transport rapidly elevate the ionospheric electron temperature—the source of a bright SAR arc. Through a substorm, the density altitude profile within the evolving ionospheric SAID channel transforms into a "fresh" F‐region trough with the E‐region valley. The ionospheric feedback instability within the depleted‐density SAID channel generates small‐scale, field‐aligned currents with parallel electric fields sufficient to produce the suprathermal electron population, exciting the STEVE and Picket Fence emissions. This approach also explains the inner electromagnetic structure of intense SAID, which is consistent with fine optical structures in STEVE and Picket Fence. Key Points: Nightside Stable Auroral Red (SAR) arcs emerge and follow the evolution of the fasttime subauroral ion drifts (SAID) until the ensuing emergence of Strong Thermal Emission Velocity Enhancement (STEVE)Density trough formation with the E‐region valley initiates the emergence of STEVE and Picket Fence underneath of the precursor SAR arcSmall‐scale parallel electric fields created by the ionospheric feedback instability in the low‐density SAID channel make STEVE and Picket Fence [ABSTRACT FROM AUTHOR]

The paper presents the results of an experimental investigation assessing the influence of the openings typology and position on the cyclic response of masonry‐infilled reinforced concrete frames. The experimental program consisted of seven 2/3 scale square frame specimens infilled with hollow clay bricks, which were subjected to quasi‐static lateral cyclic tests up to large drifts. A reference bare frame was also tested for comparison. The specimens included solid infill walls, infills with door openings, and infills with window central and eccentric openings. The experimental responses of the specimens were analyzed in terms of strength, stiffness, energy dissipation capacity, and equivalent damping, and were compared to those of the reference bare frame and fully infilled frame. Results revealed a significant modification of the resisting mechanisms as a function of the typology and position of the openings with respect to the case of a fully infilled frame, although the lateral resisting capacity was not substantially modified. On the other hand, it was observed that the achievement of the limit state thresholds occurred at substantially different interstorey drifts, indicating different damage metrics. Simple regression analyses, based on the experimental results of this study and from the literature, were finally conducted to interpret the modification of the peak force and of the corresponding drift as a function of synthetic parameters defining the opening arrangement. [ABSTRACT FROM AUTHOR]

Strong Thermal Emission Velocity Enhancement (STEVE), is a captivating optical phenomenon typically observed in the mid‐latitude ionosphere. This paper presents an intriguing observation of a STEVE event at high‐latitudes, approximately 10 degrees poleward of previously documented observations. This event was recorded in Yellowknife, Canada, by a TREx RGB imager and a citizen scientist. Swarm satellites traversed the latitude of the observation, measuring extreme westwards ion drift velocities exceeding 4 km/s. Such velocities are more typically associated with the subauroral region located at mid‐latitudes, rather than at the high‐latitudes reported here. Significantly, this event occurred without a substorm, which differs from previous STEVE observations. While high‐latitude radars detected fast ionospheric equatorward flows, GOES satellite did not record any injections. These observations suggest that the inner magnetosphere is highly inflated. This unique case study raises new questions surrounding subauroral dynamics and the influence of magnetospheric configurations on ionospheric responses. Plain Language Summary: Strong Thermal Emission Velocity Enhancement, also known as STEVE, is a fascinating nighttime optical phenomenon that takes place in the upper part of Earth's atmosphere. It can be easily recognized by its distinctive appearance as a narrow white‐mauve arc that is associated with strong westward flows and is situated just equatorward of the auroral oval. Previous research has shown that STEVE events occur together with intense ionospheric flows and occur after specific disturbances in the near‐Earth space environment known as substorms. They have found that substorms are important for creating the special conditions that lead to STEVE and other subauroral enhancements. In our study, we focus on a unique STEVE event that did not occur after a substorm. Furthermore, this observation took place under remarkably quiet solar wind conditions; nevertheless, strong ionospheric flows were recorded. This unusual case raises new questions about the atmospheric responses and how it is affected by the configuration of the magnetic field in space. By investigating these special circumstances, we hope to learn more about STEVE and its causes, which will help us advance our knowledge in the complex ionosphere‐magnetosphere‐solar wind coupled system. Key Points: Non‐storm and non‐substorm Strong Thermal Emission Velocity Enhancement (STEVE) occurrenceStrong subauroral flows during quiet geomagnetic conditionsThe ionospheric electrodynamics of this STEVE event differ from previous studies [ABSTRACT FROM AUTHOR]

Cognitive dysfunction constitutes a core characteristic of schizophrenia spectrum disorders (SZ). Specifically, deficits in updating generative models (i.e., cognitive flexibility) and shielding against distractions (i.e., cognitive stability) are considered critical contributors to cognitive impairment in these patients. Here, we examined the structural integrity of frontostriatal networks and their associations with reduced cognitive stability and flexibility in SZ patients. In a sample of 21 patients diagnosed with SZ and 22 healthy controls, we measured gray matter volume (GMV) using structural MRI. Further, cognitive stability and flexibility were assessed using a switch‐drift paradigm, quantifying the successful ignoring of distracters and detection of rule switches. Compared to controls, patients showed significantly smaller GMV in the whole brain and three predefined regions of interest: the medial prefrontal cortex (mPFC), inferior frontal gyrus (IFG), and caudate nucleus (CN). Notably, GMV in these areas positively correlated with correct rule‐switch detection but not with ignoring rule‐compatible drifts. Further, the volumetric differences between SZ patients and controls were statistically explainable by considering the behavioral performance in the switch‐drift task. Our results indicate that morphological abnormalities in frontostriatal networks are associated with deficient flexibility in SZ patients and highlight the necessity of minimizing neurodevelopmental and progressive brain atrophy in this population. Cognitive dysfunction constitutes a core characteristic of schizophrenia spectrum disorders (SZ). The current study indicates that morphological abnormalities in frontostriatal networks are associated with deficient cognitive flexibility in SZ patients and highlight the necessity of minimizing neurodevelopmental and progressive brain atrophy in this population. [ABSTRACT FROM AUTHOR]

Background and Objective: Near‐infrared spectroscopy is an established tool for the estimation of different nutrients in diverse sample matrices. Of these, near‐infrared transmittance (NIT) has very wide usage in whole grain analysis for oil, protein, and other macronutrients. NIT spectra obtained from samples are regressed with actual laboratory values for developing prediction models. However, the spectra obtained are sloppy, slightly noisy, and show baseline drifts. To increase the resolution and signal‐to‐noise ratio, derivatives are common preprocessing tools, typically implemented along with smoothing. Findings: A systematic study on different derivatives (1, 2, and 3) and gaps (2–90) was performed. The germplasm set with high variability for protein content (8.63%–19.56%) was used, and regression models were developed using the modified partial least squares method. Among all, the second‐order derivative gave best‐fit models; hence, the results of the gap with second‐order derivatives are studied in detail. The plot of R2 for external validation set with different gaps at second‐order gave three peaks, namely, at 47, 60, (69, 70, 71) where the highest R2 (0.985) was obtained for the third peak having three consecutive gap segments. Conclusion: Hence, math treatment (2, 70, 2, 1) was finalized considering stability where a high residual prediction deviation of 7.149 and a low bias of (0.021) was obtained. A paired t test and reliability test between predicted and laboratory values confirmed nonsignificant differences between them. Thus, the developed model is robust and precise and can be utilized in high throughput screening of wheat germplasm. Significance and Novelty: Better performance at second derivative and higher gap can be used for developing robust models with low bias by avoiding multi‐collinearity, which is usually a limitation in multi‐variate analysis. [ABSTRACT FROM AUTHOR]

In this study, we investigate the impacts of the 17 March 2013 strong geomagnetic storm on the wholly coupled Solar Wind‐Magnetosphere‐Ionosphere‐Thermosphere system‐of‐systems. Obtained from multipoint observations, our new results show (1) the solar‐wind Alfven waves propagating antisunward in the sheath region and (2) oscillating solar wind interplanetary magnetic field (IMF) and electric (E) field (IEF EY) that powered (3) rigorous dayside and nightside flux transfer events (FTEs) when (4) the nightside‐reconnection‐related short circuiting led to fast‐time Subauroral Ion Drifts (SAID) and Subauroral Polarization Streams (SAPS) E field development across the inner‐magnetosphere plasmapause where the solar‐wind Alfven waves (4) transitioned into kinetic Alfven waves (5) fueling the hot zone. Also, the antisunward solar‐wind Alfven waves (6) drove enhanced large‐scale region‐1 field‐aligned currents creating (7) undershielding conditions (8) allowing the dawn‐to‐dusk convection E field's earthward penetration, and (9) generated increased solar‐wind kinetic energy, which became deposited (10) to the ionosphere increasing the ionospheric electron temperature (by the downward flowing suprathermal electron fluxes) and (11) to the thermosphere oscillating the neutral winds and increasing the neutral temperature, and finally leading to (12) the development of bright stable auroral red (SAR) arcs in (13) the enhanced SAID/SAPS flow channels (FCs) developed during FTEs, (14) demonstrated with FC‐2 and FC‐3 events, in the enhanced polar convection that (15) the Rice Convection Model could reproduce. Finally, we conclude the antisunward‐propagating large‐amplitude solar‐wind Alfven waves' ultimate significant role in creating the favorable conditions for the various phenomena documented with the new observational results (1–14). Plain Language Summary: We investigate the wholly coupled Solar Wind‐Magnetosphere‐Ionosphere‐Thermosphere (SW‐M‐I‐T) system‐of‐systems operational during the 17 March 2013 strong geomagnetic storm. Results show the development of two significant phenomena in the coupled SW‐M system: (a) the region 1 field‐aligned currents and (b) the antisunward solar‐wind Alfven waves. While (a) created undershielding conditions allowing the dawn‐to‐dusk electric field (Edd) earthward propagation, (b) drove (B field, E field, wind) oscillations and generated kinetic energy (up to ∼400 TW) that became deposited (up to ∼5 TW) into the magnetosphere efficiently (up to ∼2.5%). In the coupled M‐I system, the kinetic energy drove reconnection events while the Edd convected the plasma in a two‐cell pattern. During nightside reconnection, the earthward injected ring current (RC) protons led to the development of the hot zone and conjugate large‐scale E fields near/across the plasmapause, while the downward heat flux channeled into the ionosphere elevated the electron temperature (Te). In the coupled I‐T system, the elevated Te increased the thermospheric neutral temperature (Tn) and both (Te and Tn) ignited the stable auroral red arc while the thermospheric neutral winds became oscillatory because of the antisunward solar‐wind Alfven waves that acted as the ultimate driver of the wholly coupled SW‐M‐I‐T system‐of‐systems operational. Key Points: Solar‐wind Alfven waves led to SAID/SAPS development via reconnection and transitioned into kinetic Alfven waves fueling the hot zoneEnhanced R1 FACs led to undershielding permitting the dawn‐to‐dusk convection E field's earthward penetration (to L ≈ 6 RE) on the nightsideOscillating thermospheric neutral winds and neutral temperature increase led to the development of bright SAR arcs [ABSTRACT FROM AUTHOR]

This paper introduces a novel pocket‐type dissipative rocking connection for self‐centering tubular steel bridge piers. Unlike typical self‐centering systems, this connection does not utilize post‐tensioned tendons and relies solely on gravity load for re‐centering, but it employs a redundant mechanism to prevent geometrical instability and collapse. The connection consists of several components, including an embedded sleeve component and a ring plate bearing against the column and frictionally connected to the embedded component. During rocking, the ring plate provides two‐level energy dissipation through friction and material yielding. In this connection, any residual drift could be easily recovered by untightening bolts in the frictional connection of the ring plate. A finite element model with contact elements at surface interfaces between different components was developed to simulate the response of the connection under vertical and lateral loading. Finite element analyses and quasi‐static cyclic tests of a quarter‐scale specimen demonstrated that the connection could provide adequate lateral resistance and a flag‐shaped hysteresis response with marginal or recoverable residual displacements. Test results confirmed that the connection can sustain large lateral drifts (up to 7.6%) without structural damage. Test results also indicated that the hysteresis characteristics of the connection are highly influenced by the type and configuration of the washers in the bolt assembly of the frictional connection. The lateral strength and energy dissipation properties of the connection were greatly improved when conical spring washers were added to the bolt assembly. [ABSTRACT FROM AUTHOR]

The need for carbon‐neutralization technologies has prompted significant interest in developing materials for CO2 reduction. Donor–acceptor (D–A) based flexible porous coordination polymers {[Zn(o‐phen)(ndc)].(guest)}n, (guest = anthracene = 1‐Ant, and pyrene = 1‐Pyr) are reported as photocatalysts for CO2RR, yielding higher order CH4 product. Electron‐rich anthracene (Ant) and pyrene (Pyr) guests are confined within nanopores, forming D–A charge transfer (CT) complexes with o‐phen ligand of the host. CT interaction enhances visible light absorption and modulates excitonic properties of the photocatalyst by electronic push‐pull effect (exciton binding energy 87 meV for 1‐Ant and 104 meV for 1‐Pyr). Electron donation capability varies from Pyr to Ant, affecting catalytic properties; 1‐Ant yields 1.24 mmolg−1 of CH4 (0.47 mmolg−1 for 1‐Pyr) with CO as minor product. A mixed‐metal multivariate PCP {[Zn0.55Co0.45(o‐phen)(ndc)].(Ant)}n, (1′‐Ant) prepared based on solid‐solution approach by substituting Zn(II) with redox‐active Co(II) enhances CH4 production (2.79 mmolg−1, ≈94% selectivity). D–A CT complex harvests visible light and channels electrons to Co(II) for CO2RR. In situ DRIFTS and theoretical studies elucidate Co(II) site's role in CO2 binding and stabilizing reaction intermediates. This work underscores guest‐modulated electron transfer in PCPs for tailoring catalytic properties by introducing a redox‐active metal in a multivariate approach. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of CO2 to methane faces challenges due to the stability of CO2, unpredictable intermediates, and complex electron transfer steps. Herein, a spatial In2S3/In2O3 heterojunction with abundant S vacancies (ISIO(VS)) is obtained through facile Polyvinylpyrrolidone (PVP) treatment to reach a methane yield of 16.52 µmol·g−1·h−1 with a selectivity of 95.93%, which is the highest among reported In2S3 and In2O3 based catalysts. The work function (Wf), differential charge density, and Kelvin Probe Force Microscopy (KPFM) results confirm that S vacancies strengthen the built‐in electric field (BEF) of In2S3/In2O3 (ISIO) heterojunctions, improving carrier separation. Density functional theory (DFT) calculations reveal that S vacancies induce electron redistribution, facilitating adsorption and activation of CO2 and *CO intermediate, thus promoting hydrogenation to yield *CHO. The reaction pathway of photocatalytic CO2 reduction is revealed by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and Gibbs free energy (ΔG). The S vacancies modify electronic orbitals and the highest occupied molecular orbital (HOMO) of In atom, resulting in a stronger interaction between the catalyst and *CHO, which reduces ΔG*CHO and regulates the selectivity of CH4. This study paves a new avenue for the design of photocatalysts with highly selective reduction of CO2 to CH4 through defect engineering. [ABSTRACT FROM AUTHOR]