bluuebunny/crossref_metadata_2025_split huggingface dataset:
Faint Space Target Information Extraction Based on Small Aperture Telescope in Complex Background
Authors: Jiang Ping , Xie Yaoqin , Wu Sijia , Wang Tangsheng , Li Yalan 
Published: October 2024

AbstractThere are many problems in space debris monitoring with ground‐based telescopes, such as too many stars in the same field of view, uneven background and optical distortion in the optical system. We propose a two‐stage weak debris detection algorithm. In the first stage, wavelet transform is used to extract different components of three frames of images, and the median of corresponding components of the images is taken respectively to eliminate the influence of stars. In the second stage, an improved version of the faint space target extraction based on principal component analysis. The algorithm uses a smooth‐detection idea to extract target information. Based on a 150 mm aperture telescope, we improved the existing method of faint space debris extraction based on principal component analysis by introducing the smooth‐detection idea, and transformed the target detection problem into the separation problem of sparse matrix and low‐rank matrix. We applied a certain preprocessing consisting of wavelet‐based star removal and median pre‐filtering to keep as little noise and other contaminants as possible. After experimental measurements by observers, the algorithm demonstrated advanced detection capabilities on multiple indicators.
Intermediate Wave Scale Rocky Bottom Variability for the Nearshore Along California
Authors: MacMahan Jamie , Thornton Ed , Dressel Stef , Cook Mike 
Published: October 2024

AbstractApproximately 75% of the world's and California's shores are rocky. Rocky shores are of biological interest owing to their diverse and productive species assemblages, where waves and currents play a critical role in larval dispersal and recruitment. Surface variability for nearshore rocky bottoms at intermediate wave scale is described for the first time using existing high‐resolution bathymetric surveys extending the length of California. The vertical variability of rocky shores is three times larger than measured coral reefs at the reef scale of . The ensemble‐averaged, normalized, wavenumber elevation spectra are self‐similar, with at least two negative power‐law slope regions of 1.3 indicating rough bottoms and 2.75 at high wavenumbers indicating smoother‐filled depressions. The ensemble statistics for rocky bottoms appear isotropic based on their cross‐shore and alongshore variances and wave number slope spectra being statistically equal. Isotropy is attributed to wave erosion over time that only occurs in the nearshore ocean region. A Fourier spectral representation of the bottom boundary condition, , is developed for wave and current‐driven hydrodynamic models along rocky coasts. The model has an error of less than 2% relative to the observed spectral data for reconstructive profiles and surfaces.
Projecting Large Fires in the Western US With an Interpretable and Accurate Hybrid Machine Learning Method
Authors: Li Fa , Zhu Qing , Yuan Kunxiaojia , Ji Fujiang , Paul Arindam , Lee Peng , Radeloff Volker C. , Chen Min 
Published: October 2024

AbstractMore frequent and widespread large fires are occurring in the western United States (US), yet reliable methods for predicting these fires, particularly with extended lead times and a high spatial resolution, remain challenging. In this study, we proposed an interpretable and accurate hybrid machine learning (ML) model, that explicitly represented the controls of fuel flammability, fuel availability, and human suppression effects on fires. The model demonstrated notable accuracy with a F1‐score of 0.846 ± 0.012, surpassing process‐driven fire danger indices and four commonly used ML models by up to 40% and 9%, respectively. More importantly, the ML model showed remarkably higher interpretability relative to other ML models. Specifically, by demystifying the “black box” of each ML model using the explainable AI techniques, we identified substantial structural differences across ML fire models, even among those with similar accuracy. The relationships between fires and their drivers, identified by our model, were aligned closer with established fire physical principles. The ML structural discrepancy led to diverse fire predictions and our model predictions exhibited greater consistency with actual fire occurrence. With the highly interpretable and accurate model, we revealed the strong compound effects from multiple climate variables related to evaporative demand, energy release component, temperature, and wind speed, on the dynamics of large fires and megafires in the western US. Our findings highlight the importance of assessing the structural integrity of models in addition to their accuracy. They also underscore the critical need to address the rise in compound climate extremes linked to large wildfires.
High Resolution (30 m) Burned Area Product Improves the Ability for Carbon Emission Estimation in Africa
Authors: Qi Baoye , Zhang Zhaoming , Long Tengfei , He Guojin , Wang Guizhou , Peng Yan , Xu Zekun 
Published: October 2024

AbstractFire significantly contributes to greenhouse gas emissions. The current global burned area (BA) products mainly have coarse native spatial resolution, which leads to underestimation of global BA and carbon emissions from biomass burning. Performances of BA products in Africa from GABAM (30 m), MCD64A1 (500 m), GFED4s (0.25°), FireCCI51 (250 m), and GFED5 (0.25°) were compared. From 2014 to 2020, GFED5 detected the most BA, 1.58 times more than GABAM during the same period. GABAM detected 0.09 Mkm2 more burned area than FireCCI51 on average. From 2014 to 2016, GABAM detected an average of 2.99 Mkm2 of BA in Africa, which was 1.03 times more than GFED4s. From 2014 to 2021, the average African BA derived from GABAM was 2.89 Mkm2, 1.22 times more than MCD64A1. The increase in BA will inevitably lead to an increase in the estimation of carbon emissions from biomass burning. Based on GABAM products and GFED framework, we estimated the average vegetation burning carbon emissions in Africa from 2014 to 2021 to be 1113.25 Tg, which is higher than GFED4s' carbon emissions in the same time period. This shows that the use of high‐resolution (30 m) burned area products to estimate carbon emissions can effectively avoid the underestimation of overall fire carbon emissions.
Magnitude Clustering During Stick‐Slip Dynamics on Laboratory Faults
Authors: Khajehdehi Omid , Goebel Thomas H. W. , Dresen Georg , Davidsen Jörn 
Published: October 2024

AbstractWe present an analysis of magnitude clustering of microfractures inferred from acoustic emissions (AEs) during stick‐slip (SS) dynamics of faulted Westerly granite samples in frictional sliding experiments, with and without fluids, under triaxial loading with constant displacement rate. We investigate magnitude clustering in time across periods during, preceding and after macroscopic slip events on laboratory faults. Our findings reveal that magnitude clustering exists such that subsequent AEs tend to have more similar magnitudes than expected. Yet, this clustering only exists during macroscopic slip events and is strongest during major slip events in fluid‐saturated and dry samples. We demonstrate that robust magnitude clustering arises from variations in frequency‐magnitude distributions of AE events during macroscopic slip events. These temporal variations indicate a prevalence of larger AE events right after (0.3–3 s) the SS onset. Hence, magnitude clustering is a consequence of non‐stationarities.
Combined Impacts of Temperature, Sea Ice Coverage, and Mixing Ratios of Sea Spray and Dust on Cloud Phase Over the Arctic and Southern Oceans
Authors: Dietel Barbara , Andersen Hendrik , Cermak Jan , Stier Philip , Hoose Corinna 
Published: October 2024

AbstractWe analyze the importance of cloud top temperature, dust aerosol, sea salt aerosol, and sea ice cover for the thermodynamic phase of low‐level, mid‐level, and mid to low‐level clouds observed by CloudSat/CALIPSO over the Arctic and the Southern Ocean using an explainable machine learning technique. As expected, the cloud top temperature is found to be the most important parameter for determining cloud phase. The results show also a predictive power of sea salt and sea ice on the phase of low‐level clouds, while in mid‐level clouds dust shows predictive power. Over the Southern Ocean, strong zonal winds coincide with the aerosol distribution. While they can produce high mixing ratios of sea spray at lower levels, the strong zonal winds may prevent the pole‐ward transport of dust. Sea ice may prevent the release of sea salt aerosols and marine organic aerosols leading to higher liquid fractions in clouds over sea ice.
Aluminum and Iron Effects on the Electrical Conductivity of the Dense Hydrous Magnesium Silicate Phase E
Authors: Zhao Bin , Mashino Izumi , Yoshino Takashi 
Published: October 2024

AbstractThe electrical conductivity of pure and Al/Fe‐bearing phase E was measured up to 950 K at 15 GPa using a complex impedance spectroscopy. Pure phase E shows comparable conductivity to that of phase D, and a few orders of magnitude higher than that of phase A and super‐hydrous phase B. Al‐bearing phase E does not exhibit a conductivity difference, while a certain amount of incorporated Fe prominently increases its electrical conductivity by a factor of 4. Unlike the sole substitution 2Al3+→Mg2++Si4+ in phase D and H, H+ is likely involved in the substitution. Proton conduction is the dominant conduction mechanism, while small polaron conduction becomes dominant with increasing Fe content. Phase E in subducted slabs at depth of the upper transition zone cannot explain the high electrical conductivity anomalies beneath the Philippine Sea or Northeast China. Other mechanisms such as dehydration of hydrous minerals is needed to account for them.
Elevated Mixing Estimates and Trapped Near‐Inertial Internal Waves on the Inshore Flank of the New Guinea Coastal Undercurrent From Sustained Glider Observations in the Solomon Sea
Authors: Johnston T. M. Shaun , Rudnick Daniel L. , Kessler William S. 
Published: October 2024

AbstractThe Solomon Sea is a major contributor to (a) the volume transport into the Equatorial Undercurrent and (b) the associated heat transport, which has an order one effect on interannual temperature variability on the equator according to previous work. The narrow western boundary current (New Guinea Coastal Undercurrent, NGCU) merges with the broad, shallow North Vanuatu Jet within 100 km of the southern entry to the sea, which implies mixing. Existing estimates from observations suggest mixing is larger than in models with different mixing parameterizations, which produce disparate properties of these exiting waters. Here, we use sustained underwater glider measurements across the Solomon Sea from 2007 to 2020 to examine the spatial variability of mixing estimates and internal waves. We estimate diffusivity via a finescale parameterization using the vertical strain of isopycnal displacements from internal waves. A typical accuracy of this parameterization when compared to turbulence measurements is within a factor of 2–3. Our results and previous observations in this area agree within this factor. Our main results are: (a) vertical diffusivity estimates are about on the inshore, anticyclonic side of the NGCU, which are 10–100 times higher than offshore and (b) elevated near‐inertial internal wave (NIW) amplitudes are also found inshore. Taken together, these results suggest trapping of NIW by the anticyclonic vorticity of the NGCU leads to the elevated mixing within 100 km of the entry to the Solomon Sea.
Electron Density Profile Derived From Ionogram Using Ray Tracing Inversion Method
Authors: Jiang Qi , Lei Jiuhou , Yue Xinan , Ren Dexin , Huang Fuqing , Luan Xiaoli , Li Guozhu 
Published: October 2024

AbstractThe ionosonde is widely used for detecting electron density profiles below the F2 peak altitude. Extracting precise profiles from ionograms is crucial, as it serves as a significant data source for ionospheric studies and applications. In our study, we utilized the ray tracing profile inversion method (RTPI) to derive more realistic electron density profiles from the ionosonde observations. By comparing the electron density profiles inverted by RTPI method with and without geomagnetic field against the profiles observed by Incoherent Scatter Radar (ISR) plasma lines, we validated the high precision of the RTPI with magnetic field effect method. The results showed that the average height difference and average peak height difference between profiles inverted by RTPI and plasma line observations are less than 10 and 5 km, respectively. Additionally, we quantified the errors associated with the geomagnetic field effect. It would cause an ∼8–10 km overestimation in true height and a ∼10%–15% underestimation in electron density if the geomagnetic field effect is not considered. These errors induced by the magnetic field accumulate with the frequency of the radio waves. Moreover, we conducted a comparative analysis of simulated echo traces using profiles with different E‐layer shapes. It was demonstrated that the key parameters of the bottom structure have a significant impact on ionogram retrieval, while the E‐layer shape has negligible influence on inversion. Furthermore, we analyzed echo traces simulated using ray tracing with and without collision. The collision effect has weak effect on the delay of the radio waves.
A Transtensional Fault Zone on the Northeastern Margin of the Tibetan Plateau: Millennial Earthquake Recurrence and High Earthquake Hazard
Authors: Guo Peng , Han Zhujun , Gai Hailong , Niu Pengfei , Li Jiani 
Published: October 2024

AbstractThe seismic gaps between ruptures of large earthquakes in tectonically active deformation zones are usually considered to be dangerous areas for future earthquakes. The Western Tianzhu Basin fault (WTBF) with an oblique normal motion is located in the middle of the Tianzhu seismic gap between the M 8.5 Haiyuan and M 8.0 Gulang earthquakes, NE Tibetan Plateau. The faulting activity of the WTBF is key to understanding the seismic hazards of the seismic gap, but it remains poorly constrained. Using satellite images, field investigations, paleoseismic trenching, and radiocarbon dating, we found that the WTBF produced seven paleoearthquakes since ∼8,000 cal. yr BP, with the latest event occurring at 1,005 ± 584 cal. yr BP, yielding an average recurrence interval of 1,102 ± 100 yr and a coefficient of variation of 0.38, indicating that it features a millennial quasi‐periodic recurrence. Based on the comparative analysis of geometry, kinematics, and tectonic activity, we suggest that the Tianzhu seismic gap can be divided into three sections and is characterized by a segmented rupture pattern. Among them, the WTBF and Jinqianghe fault exhibit similar geometry and kinematics and together form the ∼55 km‐long Jinqianghe‐Tianzhu transtensional fault zone (JTTFZ) that is capable of producing earthquakes of Mw 7.2. Given the long elapsed time since the latest event and strong seismogenic potential, it is believed that the JTTFZ poses a high seismic hazard. Our results enhance the understanding of the high seismic hazard in seismic gaps and provide new insights into the seismic rupture behavior in the NE Tibetan Plateau.
Longitudinal association of homocysteine with depressive and anxiety symptoms among urban adults: healthy aging in neighborhoods of diversity across the life span study
Authors: Georgescu Michael F. , Beydoun May A. , Maino Vieytes Christian A. , Fanelli-Kuczmarski Marie T. , Ashe Jason , Beydoun Hind A. , Hossain Sharmin , Noren Hooten Nicole , Evans Michele K. , Zonderman Alan B. 
Published: October 2024

AbstractLongitudinal associations of homocysteine (HCY) with depressive symptoms scores among urban adults remain under-studied, especially across sex, race and levels of anxiety. We examined longitudinal associations of homocysteine (HCY) with depressive symptoms scores among urban adults, before and after stratifying by sex, race and anxiety level, using data from 1460 Healthy Aging in Neighborhoods of Diversity across the Lifespan Study (HANDLS) participants aged 30–64 y at v1 (2004–2009), followed across 3 visits up to 2017. In addition to LnHcyv1, we used group-based trajectory models predicting z-transformed likelihood of greater LnHcy with age (Hcytraj). Total and domain-specific depression symptoms were scored using Center for Epidemiologic Studies Depression (CES-D) scale. Mixed-effects linear regression models and Cox proportional hazards models were utilized. A positive association was found between baseline LnHcyv1 and CES-D total scores in reduced socio-demographic- adjusted Model 1 (β (standard error [SE]) = + 2.337 (0.902), P = 0.010), a relationship slightly attenuated in fully adjusted Model 2 (Model 1 adjusting for lifestyle and health factors) with a β (SE) = + 1.825 (0.883), P = 0.039. Individuals with lower anxiety levels experienced faster CES-D domain 2 score annualized increase over time (interpersonal problems) with higher LnHcyv1 (β (SE) = 0.041 (0.018), P = 0.024). Hcytraj was linked to incident elevated depressive symptoms (CES-D total score ≥16) overall (fully adjusted model: HR = 1.09, 95% CI: 1.03–1.14, P = 0.001), particularly among women and those living in poverty. Baseline and “high trajectory” of LnHcy were positively associated with depressive symptoms and elevated depressive symptom incidence, in a sex-, race-, poverty status- and anxiety-level specific manner.
LAP2α orchestrates alternative lengthening of telomeres suppression through telomeric heterochromatin regulation with HDAC1: unveiling a potential therapeutic target
Authors: Wang Bing , Kou Haomeng , Wang Yuwen , Zhang Qi , Jiang Duo , Wang Juan , Zhao Ziqin , Zhou Yao , Zhang Miaomiao , Sui Lei , Zhao Mingfeng , Liu Yancheng , Liu Yang , Shi Lei , Wang Feng 
Published: October 2024

AbstractIn response to the challenge of telomere attrition during DNA replication, cancer cells predominantly employ telomerase or, in 10–15% of cases, the alternative lengthening of telomeres (ALT). The intricate details of ALT, however, remain elusive. In this study, we unveil that the knockdown of lamina-associated polypeptide 2 alpha (LAP2α) in ALT cells results in telomere dysfunction, triggering a notable increase in ALT-associated hallmarks, including high frequencies of PML bodies (APBs), C-rich extrachromosomal circles (C-circles), and telomere sister chromatid exchange (T-SCE). Furthermore, LAP2α emerges as a crucial player in break-induced telomere replication for telomerase-positive cells following telomeric double-strand breaks. Mechanistically, our investigation suggests that LAP2α may influence the regulation of the heterochromatic state of telomeres, thereby affecting telomeric accessibility. In line with our findings, LAP2α expression is markedly reduced in ALT-positive osteosarcoma. And the use of methotrexate (MTX) can restore the heterochromatin state altered by LAP2α depletion. This is evidenced by a significant inhibition of tumor proliferation in ALT-positive patient-derived xenograft (PDX) mouse models. These results indicate the important role of LAP2α in regulating ALT activity and offer insights into the interplay between lamina-associated proteins and telomeres in maintaining telomere length. Importantly, our findings may help identify a more appropriate target population for the osteosarcoma therapeutic drug, MTX.
Unidirectional ray polaritons in twisted asymmetric stacks
Authors: Álvarez-Cuervo J. , Obst M. , Dixit S. , Carini G. , F. Tresguerres-Mata A. I. , Lanza C. , Terán-García E. , Álvarez-Pérez G. , Álvarez-Tomillo L. F. , Diaz-Granados K. , Kowalski R. , Senerath A. S. , Mueller N. S. , Herrer L. , De Teresa J. M. , Wasserroth S. , Klopf J. M. , Beechem T. , Wolf M. , Eng L. M. , Folland T. G. , Tarazaga Martín-Luengo A. , Martín-Sánchez J. , Kehr S. C. , Nikitin A. Y. , Caldwell J. D. , Alonso-González P. , Paarmann A. 
Published: October 2024

AbstractThe vast repository of van der Waals (vdW) materials supporting polaritons offers numerous possibilities to tailor electromagnetic waves at the nanoscale. The development of twistoptics—the modulation of the optical properties by twisting stacks of vdW materials—enables directional propagation of phonon polaritons (PhPs) along a single spatial direction, known as canalization. Here we demonstrate a complementary type of directional propagation of polaritons by reporting the visualization of unidirectional ray polaritons (URPs). They arise naturally in twisted hyperbolic stacks with very different thicknesses of their constituents, demonstrated for homostructures of $$\alpha$$
α
-MoO3 and heterostructures of $$\alpha$$
α
-MoO3 and $$\beta$$
β
-Ga2O3. Importantly, their ray-like propagation, characterized by large momenta and constant phase, is tunable by both the twist angle and the illumination frequency. Apart from their fundamental importance, our findings introduce twisted asymmetric stacks as efficient platforms for nanoscale directional polariton propagation, opening the door for applications in nanoimaging, (bio)-sensing, or polaritonic thermal management.
The GIAB genomic stratifications resource for human reference genomes
Authors: Dwarshuis Nathan , Kalra Divya , McDaniel Jennifer , Sanio Philippe , Alvarez Jerez Pilar , Jadhav Bharati , Huang Wenyu , Mondal Rajarshi , Busby Ben , Olson Nathan D. , Sedlazeck Fritz J. , Wagner Justin , Majidian Sina , Zook Justin M. 
Published: October 2024

AbstractDespite the growing variety of sequencing and variant-calling tools, no workflow performs equally well across the entire human genome. Understanding context-dependent performance is critical for enabling researchers, clinicians, and developers to make informed tradeoffs when selecting sequencing hardware and software. Here we describe a set of “stratifications,” which are BED files that define distinct contexts throughout the genome. We define these for GRCh37/38 as well as the new T2T-CHM13 reference, adding many new hard-to-sequence regions which are critical for understanding performance as the field progresses. Specifically, we highlight the increase in hard-to-map and GC-rich stratifications in CHM13 relative to the previous references. We then compare the benchmarking performance with each reference and show the performance penalty brought about by these additional difficult regions in CHM13. Additionally, we demonstrate how the stratifications can track context-specific improvements over different platform iterations, using Oxford Nanopore Technologies as an example. The means to generate these stratifications are available as a snakemake pipeline at https://github.com/usnistgov/giab-stratifications. We anticipate this being useful in enabling precise risk-reward calculations when building sequencing pipelines for any of the commonly-used reference genomes.