bluuebunny/crossref_metadata_2025_split huggingface dataset:
Why Are Mountaintops Cold? The Transition of Surface Lapse Rate on Dry Planets
Authors: Fan Bowen , Jansen Malte F. , Mischna Michael A. , Kite Edwin S. 
Published: November 2023

AbstractUnderstanding surface temperature is important for habitability. Recent work on Mars has found that the dependence of surface temperature on elevation (surface lapse rate) converges to zero in the limit of a thin CO2 atmosphere. However, the mechanisms that control the surface lapse rate are still not fully understood. It remains unclear how the surface lapse rate depends on both greenhouse effect and surface pressure. Here, we use climate models to study when and why “mountaintops are cold.” We find the tropical surface lapse rate increases with the greenhouse effect and with surface pressure. The greenhouse effect dominates the surface lapse rate transition and is robust across latitudes. The pressure effect is important at low latitudes in moderately opaque (τ ∼ 0.1) atmospheres. A simple model provides insights into the mechanisms of the transition. Our results suggest that topographic cold‐trapping may be important for the climate of arid planets.
SunSCC: Segmenting, Grouping and Classifying Sunspots From Ground‐Based Observations Using Deep Learning
Authors: Sayez Niels , De Vleeschouwer Christophe , Delouille Véronique , Bechet Sabrina , Lefèvre Laure 
Published: November 2023

AbstractWe propose a fully automated system to detect, aggregate, and classify sunspot groups according to the McIntosh scheme using ground‐based white light (WL) observations from the USET facility located at the Royal Observatory of Belgium. The sunspot detection uses a Convolutional Neural Network (CNN), trained from segmentation maps obtained with an unsupervised method based on mathematical morphology and image thresholding. Given the sunspot mask, a mean‐shift algorithm is used to aggregate individual sunspots into sunspot groups. This algorithm accounts for the area of each sunspot as well as for prior knowledge regarding the shape of sunspot group. A sunspot group, defined by its bounding box and location on the Sun, is finally fed into a CNN multitask classifier. The latter predicts the three components Z, p, and c in the McIntosh classification scheme. The tasks are organized hierarchically to mimic the dependency of the second (p) and third (c) components on the first (Z). The resulting CNN‐based segmentation is more accurate than classical unsupervised methods, with an enhancement up to 16% of F1 score in detection of the smallest sunspots, and it is robust to the presence of clouds. The automated clustering method was able to separate groups with an accuracy of 80%, when compared to hand‐made USET sunspot group catalog. The CNN‐based sunspot classifier shows comparable performances to methods using continuum as well as magnetogram images recorded by instruments on space mission. We also show that an ensemble of classifiers allows differentiating reliable and potentially incorrect predictions.
Seasonal Seismic Velocity Variations Measured Using Seismic Noise Autocorrelations to Monitor the Dynamic of Aquifers in Greece
Authors: Delouche E. , Stehly L. 
Published: November 2023

AbstractMonitoring groundwater levels in aquifers is crucial for water resources management on a global scale. In Greece, water stress is particularly high due to the expansion of agricultural land, urbanization and tourism, leading to aquifer over‐exploitation. In this study, we investigate the possibility of monitoring groundwater reservoirs from seismic velocity changes (δv/v) measured using noise autocorrelations. The results obtained at short periods (0.5–3 s) indicate that in several regions, seismic wave velocity varies according to an annual cycle mainly controlled by aquifer loading and discharge. We also predict seismic velocity variations from a simple model using precipitation records. In addition, this model provides a proxy for the characteristic time of aquifer discharge rate and allows us to distinguish shallow alluvial aquifers (∼100 m) from deep karst systems (∼1 km). Finally, we study the effect of water pumping from groundwater reservoirs. To that end, we combine Global Positioning System (GPS), hydraulic heads and velocity variations measurement. The results indicate that confined and unconfined aquifers respond differently. While for unconfined aquifers, pumping water implies an uplift of the surface, we show that for confined aquifers a subsidence occurs, due to the consolidation of the sediments at depth. Being an in‐situ and volumetric measurement, the δv/v is primarily sensitive to the amount of water stored in the entire aquifer system, whereas GPS measurements provide the deformation at the surface induced by both deep sediment compaction and water level variations. These observations show that GPS, hydraulic head, and δv/v are complementary tools to monitor aquifers.
Along‐Strike Segmentation of Seismic Tremor and Its Relationship With the Hydraulic Structure of the Subduction Fault Zone
Authors: Farge Gaspard , Jaupart Claude , Frank William B. , Shapiro Nikolai M. 
Published: November 2023

AbstractAlong the strike of subduction zones, tectonic tremor episodicity is segmented on a geologic scale. Here, we study how this segmentation reflects large‐scale variations of the structure and conditions of the fault interface where tremor is generated. We try to understand which properties of the hydraulic system of the fault allow elementary tremor sources to synchronize, leading to the emergence of long‐period, large‐scale episodic activity. We model tremor sources as being associated with rapid openings of low‐permeability valves in the fault zone, which channels the upward flow of metamorphic fluids. Valve openings cause pressure transients that allow interaction between sources. In such a system, tremor activity is thus controlled by unsteady fluid circulation. Using numerical simulations of fluid flow, we explore the impact of valve spatial distribution and fluid flux on the emergence of large‐scale patterns of tremor activity. We show that when valves are densely distributed and submitted to near‐critical input flux, they synchronize and generate more episodic activity. Based on our model, the most periodic and spatially coherent tremor bursts should thus be emitted from segments densely populated with valves, and therefore of lower permeability than less synchronized segments. The collective activity of their valve population is responsible for fluid‐pressure cycling at the subduction scale. In the tremor zone of Shikoku, Japan, the most temporally clustered segment coincides with a downgoing seamount chain, suggesting that the segmentation of the fault zone permeability, and hence of tremor activity, could be inherited from the topography of the subducting oceanic plate.
Spatial and Temporal Variation of Mars South Polar Ice Composition From Spectral Endmember Classification of CRISM Mapping Data
Authors: Cartwright S. F. A. , Calvin W. M. , Seelos F. P. , Seelos K. D. 
Published: November 2023

AbstractMultispectral mapping data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) provide a unique opportunity to characterize south polar ice deposits at higher spectral sampling, spatial resolution, or spatiotemporal coverage than previous work. This new perspective can help constrain the nature and distribution of different mixtures of CO2 ice, H2O ice, and dust that influence the formation, evolution, and preservation of Mars climate records. We processed 1,103 CRISM observations spanning the southern summer of six Mars Years (MYs) through a combination of k‐means clustering and random forest classification. Using a set of 12 spectral endmembers directly tied to previous work with high‐resolution CRISM targeted data, we made a series of temporally restricted mosaics showing surface spectral variation over time. The mosaics show the effects of the MY 28 dust storm on the removal of the seasonal CO2 ice cap that year and reveal how this process differed from the years that followed. A mosaic showing residual ice surfaces displays broad agreement with previous compositional maps while resolving new details in the distribution of H2O ice‐rich material around the periphery of the bright CO2 ice cap. By showing how surface composition varies across a broad swath of the south polar region through time, the endmember set and classified mosaics produced in this work can provide critical context for future studies of the dynamic processes that shape south polar ice deposits.
Effects of Spring Phenology on Grassland Growth in Qilian Mountains Across Multiple Spatiotemporal Scales
Authors: Sun Yunfan , Guan Qingyu , Du Qinqin , Wang Qingzheng , Yang Xinyue , Zhang Erya 
Published: November 2023

AbstractInvestigating the differences in grassland growth and its response to advancing spring phenology and climate change across various spatiotemporal scales is crucial for the sustainable development of alpine mountain regions under a warming and wetting climate. This study analyzed the growth dynamics of grassland in the Qilian Mountains from 2000 to 2019 at seasonal and periodic scales. Using partial wavelet coherency and partial correlation analysis, we investigated the influence of temperature, precipitation, and spring phenology on grassland growth. Additionally, we quantified the dominant factors affecting grassland growth in different ecological zones and elevational gradient. The results indicated that the mean normalized difference vegetation index increased at an average rate of 1.1 and 2.8 × 10−3/year for grassland in spring and summer, respectively. Furthermore, the start of vegetation growing season (SOS) has advanced 6.0 days during 2000–2019. The dominant factor for grassland growth shifted from spring temperature to summer precipitation. The importance of SOS ranked second, significantly influencing 29.3% and 25.1% of grassland during spring and summer, respectively. Grasslands situated above 4,000 m above sea level (ASL) were more sensitive to climate change, with SOS exerting the greatest influence within the elevation range of 2,800–4,000 m ASL. Additionally, the phase difference in the time‐frequency scale of partial wavelet coherency revealed a lag effect of approximately 1 month for summer grassland growth to respond to precipitation. These findings can provide a scientific basis for optimizing global vegetation models and predicting the productivity of alpine mountain grasslands.
Geomagnetically Induced Current Mitigation in New Zealand: Operational Mitigation Method Development With Industry Input
Authors: Mac Manus D. H. , Rodger C. J. , Renton A. , Ronald J. , Harper D. , Taylor C. , Dalzell M. , Divett T. , Clilverd M. A. 
Published: November 2023

AbstractReducing the impact of Geomagnetically induced currents (GICs) on electrical power networks is an essential step to protect network assets and maintain reliable power transmission during and after storm events. In this study, multiple mitigation strategies are tested during worst‐case extreme storm scenarios in order to investigate their effectiveness for the New Zealand transmission network. By working directly with our industry partners, Transpower New Zealand Ltd, a mitigation strategy in the form of targeted line disconnections has been developed. This mitigation strategy proved more effective than previous strategies at reducing GIC magnitudes and durations at transformers at most risk to GIC while still maintaining the continuous supply of power throughout New Zealand. Under this mitigation plan, the average 60‐min mean GIC decreased for 27 of the top 30 at‐risk transformers, and the total network GIC was reduced by 16%. This updated mitigation has been adopted as an operational procedure in the New Zealand national control room to manage GIC. In addition, simulations show that the installation of 14 capacitor blocking devices at specific transformers reduces the total GIC sum in the network by an additional 16%. As a result of this study Transpower is considering further mitigation in the form of capacitor blockers. We strongly recommend collaborating with the relevant power network providers to develop effective mitigation strategies that reduce GIC and have a minimal impact on power distribution.
Groundwater Sensitivity to Climate Variations Across Australia
Authors: Fan Xinyang , Peterson Tim J. , Henley Benjamin J. , Arora Meenakshi 
Published: November 2023

AbstractGroundwater response to climate variations is often pivotal to managing groundwater sustainably. However, this relationship is rarely explicitly examined because of the complexity of surface to subsurface processes and the diverse impacts of multiple drivers, such as groundwater pumping and land use changes. In this paper, we address this challenge by proposing methods to quantify the sensitivity of groundwater level and recharge to temporal climate variability across Australia. Using the HydroSight groundwater hydrograph toolbox we first identify 1,143 out of a total of 4,350 bores as climate‐driven, where historically, head was primarily driven by climate variations. Streamflow elasticity measures are then adapted to groundwater to quantify the long‐term head and recharge sensitivity. We find that the national median sensitivity of head and recharge to precipitation change are 42 and 0.43 mm mm−1, respectively (interquartiles: 20–77 and 0.30–0.55 mm mm−1); both of which are ∼8 times that of potential evapotranspiration. Nationally, the results are spatially correlated, suggestive of large‐scale effects. The responses of head and recharge appear to be primarily related to climate type and hydrogeology. The more arid the climate, the higher the head sensitivity but the lower the recharge sensitivity. Porous media generally show higher head sensitivity than fractured media due to smaller aquifer specific yield, and again contrarily for that of recharge. These findings contribute to understanding the long‐term impact of climate change on groundwater and thus provide valuable insights for sustainable groundwater management.
Constraining Plant Hydraulics With Microwave Radiometry in a Land Surface Model: Impacts of Temporal Resolution
Authors: Holtzman Nataniel , Wang Yujie , Wood Jeffrey D. , Frankenberg Christian , Konings Alexandra G. 
Published: November 2023

AbstractVegetation water content (VWC) plays a key role in transpiration, plant mortality, and wildfire risk. Although land surface models now often contain plant hydraulics schemes, there are few direct VWC measurements to constrain these models at global scale. One proposed solution to this data gap is passive microwave remote sensing, which is sensitive to temporal changes in VWC. Here, we test that approach by using synthetic microwave observations to constrain VWC and surface soil moisture within the Climate Modeling Alliance Land model. We further investigate the possible utility of sub‐daily observations of VWC, which could be obtained through a satellite in geostationary orbit or combinations of multiple satellites. These high‐temporal‐resolution observations could allow for improved determination of ecosystem parameters, carbon and water fluxes, and subsurface hydraulics, relative to the currently available twice‐daily sun‐synchronous observational patterns. We find that incorporating observations at four different times in the diurnal cycle (such as could be available from two sun‐synchronous satellites) provides a significantly better constraint on water and carbon fluxes than twice‐daily observations do. For example, the root mean square error of projected evapotranspiration and gross primary productivity during drought periods was reduced by approximately 40%, when using four‐times‐daily relative to twice‐daily observations. Adding hourly observations of the entire diurnal cycle did not further improve the inferred parameters and fluxes. Our comparison of observational strategies may be informative in the design of future satellite missions to study plant hydraulics, as well as when using existing remotely sensed data to study vegetation water stress response.
Study of Supercooling Phenomena in Soil‐Water Systems Based on Nucleation Theory: Quantifying Supercooling Degree
Authors: Wang Chong , Li Kunyu , Cai Honghong , Wu Yumo , Lin Zhikun , Li Shuangyang 
Published: November 2023

AbstractDetermining the minimum supercooling temperature (Tsc) of unsaturated saline soils is the key scientific problem in cold‐region agricultural and engineering, and theoretical models with good predictability are urgently needed. This study establishes a framework for pore solution freezing nucleation in unsaturated saline soils, the chemical potential energy balance equation was established by determining phase transition driving force and potential energy barrier for the formation of stable crystal embryos. Finally, the physical model was constructed. By citing 46 sets of data from different researchers, the validity of the prediction results of this paper's model under different soil types and cooling rates is demonstrated, and the microscopic mechanism of supercooling occurring in the pore solution of positive permafrost is elucidated. The analysis found that electrolyte action restricts the free diffusion of molecules and promotes nucleation to occur, so that a maximum value of Tsc exists during the growth of salinity (in NaCl saline soils occurs at a solution concentration of 0.26 mol/L). Too fast cooling rate will lead to a lag in crystallization time and an increase in supercooling. The combined water content determines the Tsc when rc < 1 μm (pore size), and the effect of changes in water content and cooling rate on supercooling is more significant in small pores; the electrolyte concentration determines the Tsc when rc > 1 μm, Tsc‐max from concentration changes will be more significant in large pores. This study can provide theoretical reserves for controlling the freezing process of soils, studying the mechanism of freezing‐thawing hysteresis, and improving the related numerical calculation models.
Sex-associated differences in frequencies and prognostic impact of recurrent genetic alterations in adult acute myeloid leukemia (Alliance, AMLCG)
Authors: Ozga Michael , Nicolet Deedra , Mrózek Krzysztof , Yilmaz Ayse S. , Kohlschmidt Jessica , Larkin Karilyn T. , Blachly James S. , Oakes Christopher C. , Buss Jill , Walker Christopher J. , Orwick Shelley , Jurinovic Vindi , Rothenberg-Thurley Maja , Dufour Annika , Schneider Stephanie , Sauerland Maria Cristina , Görlich Dennis , Krug Utz , Berdel Wolfgang E. , Woermann Bernhard J. , Hiddemann Wolfgang , Braess Jan , Subklewe Marion , Spiekermann Karsten , Carroll Andrew J. , Blum William G. , Powell Bayard L. , Kolitz Jonathan E. , Moore Joseph O. , Mayer Robert J. , Larson Richard A. , Uy Geoffrey L. , Stock Wendy , Metzeler Klaus H. , Grimes H. Leighton , Byrd John C. , Salomonis Nathan , Herold Tobias , Mims Alice S. , Eisfeld Ann-Kathrin 
Published: November 2023

AbstractClinical outcome of patients with acute myeloid leukemia (AML) is associated with demographic and genetic features. Although the associations of acquired genetic alterations with patients’ sex have been recently analyzed, their impact on outcome of female and male patients has not yet been comprehensively assessed. We performed mutational profiling, cytogenetic and outcome analyses in 1726 adults with AML (749 female and 977 male) treated on frontline Alliance for Clinical Trials in Oncology protocols. A validation cohort comprised 465 women and 489 men treated on frontline protocols of the German AML Cooperative Group. Compared with men, women more often had normal karyotype, FLT3-ITD, DNMT3A, NPM1 and WT1 mutations and less often complex karyotype, ASXL1, SRSF2, U2AF1, RUNX1, or KIT mutations. More women were in the 2022 European LeukemiaNet intermediate-risk group and more men in adverse-risk group. We found sex differences in co-occurring mutation patterns and prognostic impact of select genetic alterations. The mutation-associated splicing events and gene-expression profiles also differed between sexes. In patients aged <60 years, SF3B1 mutations were male-specific adverse outcome prognosticators. We conclude that sex differences in AML-associated genetic alterations and mutation-specific differential splicing events highlight the importance of patients’ sex in analyses of AML biology and prognostication.
Chronic lymphocytic leukemia patient-derived xenografts recapitulate clonal evolution to Richter transformation
Authors: Playa-Albinyana Heribert , Arenas Fabian , Royo Romina , Giró Ariadna , López-Oreja Irene , Aymerich Marta , López-Guerra Mònica , Frigola Gerard , Beà Sílvia , Delgado Julio , Garcia-Roves Pablo M. , Campo Elías , Nadeu Ferran , Colomer Dolors 
Published: November 2023

AbstractChronic lymphocytic leukemia (CLL) is a B-cell neoplasm with a heterogeneous clinical behavior. In 5–10% of patients the disease transforms into a diffuse large-B cell lymphoma known as Richter transformation (RT), which is associated with dismal prognosis. Here, we aimed to establish patient-derived xenograft (PDX) models to study the molecular features and evolution of CLL and RT. We generated two PDXs by injecting CLL (PDX12) and RT (PDX19) cells into immunocompromised NSG mice. Both PDXs were morphologically and phenotypically similar to RT. Whole-genome sequencing analysis at different time points of the PDX evolution revealed a genomic landscape similar to RT tumors from both patients and uncovered an unprecedented RT subclonal heterogeneity and clonal evolution during PDX generation. In PDX12, the transformed cells expanded from a very small subclone already present at the CLL stage. Transcriptomic analysis of PDXs showed a high oxidative phosphorylation (OXPHOS) and low B-cell receptor (BCR) signaling similar to the RT in the patients. IACS-010759, an OXPHOS inhibitor, reduced proliferation, and circumvented resistance to venetoclax. In summary, we have generated new RT-PDX models, one of them from CLL cells that mimicked the evolution of CLL to RT uncovering intrinsic features of RT cells of therapeutical value.
Investigation into the role of the MITA-TRIM38 interaction in regulating pyroptosis and maintaining immune tolerance at the maternal-fetal interface
Authors: Liu Jun , Deng Yan , Wang An , Liu Bowen , Zhou Xi , Yin Tailang , Wang Yan , Tang Tao , Qiu Yang , Chen Jiao , Yang Jing 
Published: November 2023

AbstractThe maternal-fetal interface shares similarities with tumor tissues in terms of the immune microenvironment. Normal pregnancy is maintained due to the immunosuppressed state, but pyroptosis induced by MITA can trigger the body’s immune response and disrupt the immunosuppressed state of the maternal-fetal interface, leading to abortion. In this study, we explored the role of MITA and TRIM38 in regulating pyroptosis and maintaining the immune tolerance of the maternal-fetal interface during pregnancy. Our findings show that the interaction between MITA and TRIM38 plays a crucial role in maintaining the immunosuppressed state of the maternal-fetal interface. Specifically, we observed that TRIM38-mediated K48 ubiquitination of MITA was higher in M2 macrophages, leading to low expression levels of MITA and thus inhibiting pyroptosis. Conversely, in M1 macrophages, the ubiquitination of K48 was lower, resulting in higher expression levels of MITA and promoting pyroptosis. Our results also indicated that pyroptosis played an important role in hindering the transformation of M1 to M2 and maintaining the immunosuppressed state of the maternal-fetal interface. These discoveries help elucidate the mechanisms that support the preservation of the immune tolerance microenvironment at the maternal-fetal interface, playing a vital role in ensuring successful pregnancy.