bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluid‐Mediated Mass Transfer Between Mafic and Ultramafic Rocks in Subduction Zones
Authors: Codillo E. A. , Klein F. , Dragovic B. , Marschall H. R. , Baxter E. , Scambelluri M. , Schwarzenbach‬ E. 
Published: July 2022

AbstractMetasomatic reaction zones between mafic and ultramafic rocks exhumed from subduction zones provide a window into mass‐transfer processes at high pressure. However, accurate interpretation of the rock record requires distinguishing high‐pressure metasomatic processes from inherited oceanic signatures prior to subduction. We integrated constraints from bulk‐rock geochemical compositions and petrophysical properties, mineral chemistry, and thermodynamic modeling to understand the formation of reaction zones between juxtaposed metagabbro and serpentinite as exemplified by the Voltri Massif (Ligurian Alps, Italy). Distinct zones of variably metasomatized metagabbro are dominated by chlorite, amphibole, clinopyroxene, epidote, rutile, ilmenite, and titanite between serpentinite and eclogitic metagabbro. Whereas the precursor serpentinite and oxide gabbro formed and were likely already in contact in an oceanic setting, the reaction zones formed by diffusional Mg‐metasomatism between the two rocks from prograde to peak, to retrograde conditions in a subduction zone. Metasomatism of mafic rocks by Mg‐rich fluids that previously equilibrated with serpentinite could be widespread along the subduction interface, within the subducted slab, and the mantle wedge. Furthermore, the models predict that talc formation by Si‐metasomatism of serpentinite in subduction zones is limited by pressure‐dependent increase in the silica activity buffered by the serpentine‐talc equilibrium. Elevated activities of aqueous Ca and Al species would also favor the formation of chlorite and garnet. Accordingly, unusual conditions or processes would be required to stabilize abundant talc at high P‐T conditions. Alternatively, a different set of mineral assemblages, such as serpentine‐ or chlorite‐rich rocks, may be controlling the coupling‐decoupling transition of the plate interface.
Contrasting Sea‐Ice Algae Blooms in a Changing Arctic Documented by Autonomous Drifting Buoys
Authors: Hill Victoria , Light Bonnie , Steele Michael , Sybrandy Andrew Lowy 
Published: July 2022

AbstractNovel observations of the seasonal evolution of an ice algal bloom on the Chukchi shelf were collected by two autonomous buoys deployed 180 km apart in first‐year drifting sea ice. High attenuation of blue light in the bottom of the ice indicated considerable accumulation of ice algae biomass with derived Chlorophyll‐a concentrations (Chl a) up to 184 mg m−2. Differences in the magnitude and persistence of ice algae biomass under each buoy appear to have been driven by differences in snow thickness, as ice thickness was similar between the sites. Minimal snow cover (0.02 m) around one buoy was associated with algae growth beginning in mid‐May and lasting 70 days. The second buoy had notably more snow (0.4 m), causing ice algae production to lag behind the first site by approximately 4 weeks. The delay in growth diminished the peak of ice algae Chl a and duration compared to the first site. Light attenuation through the ice was intense enough at both buoys to have a potentially inhibiting impact on water column phytoplankton Chl a. Modeling ice algae growth with observed light intensities determined that nutrients were the limiting resource at the low snow site. In contrast, the algae at the high snow site were light‐limited and never nutrient‐limited. These data point toward changes in ice algae phenology with an earlier and longer window for growth; and nutrients rather than light determining the longevity and magnitude of production.
Effects of Snow and Remineralization Processes on Nutrient Distributions in Multi‐Year Antarctic Landfast Sea Ice
Authors: Sahashi Reishi , Nomura Daiki , Toyota Takenobu , Tozawa Manami , Ito Masato , Wongpan Pat , Ono Kazuya , Simizu Daisuke , Naoki Kazuhiro , Nosaka Yuichi , Tamura Takeshi , Aoki Shigeru , Ushio Shuki 
Published: July 2022

AbstractWe elucidated the effects of snow and remineralization processes on nutrient distributions in multi‐year landfast sea ice (fast ice) in Lützow‐Holm Bay, East Antarctica. Based on sea‐ice salinity, oxygen isotopic ratios, and thin section analyses, we found that the multi‐year fast ice grew upward due to the year‐by‐year accumulation of snow. Compared to ice of seawater origin, nutrient concentrations in shallow fast ice were low due to replacement by clean and fresh snow. In deeper ice of seawater origin (the lower half of the multi‐year fast ice column), remineralization was dominated by the degradation of organic matter. By comparison between first‐ and muti‐year ice, the biological uptake and the remineralization were dominated in relatively young ice and older ice, respectively, under the physical process of brine drainage.
Stability of the Jupiter Southern Polar Vortices Inspected Through Vorticity Using Juno/JIRAM Data
Authors: Scarica P. , Grassi D. , Mura A. , Adriani A. , Ingersoll A. , Li C. , Piccioni G. , Sindoni G. , Moriconi M. L. , Plainaki C. , Altieri F. , Cicchetti A. , Dinelli B. M. , Filacchione G. , Migliorini A. , Noschese R. , Sordini R. , Stefani S. , Tosi F. , Turrini D. 
Published: July 2022

AbstractThe Jovian InfraRed Auroral Mapper (JIRAM) onboard the NASA Juno mission monitored the evolution of Jupiter’s polar cyclones since their first observation ever in February 2017. Data acquired by JIRAM have revealed cloudy cyclones organized in a complex, yet stable geometrical pattern at both poles. Several studies have investigated the dynamics and the structure of these cyclones, to understand the physical mechanisms behind their formation and evolution. In this work, we present vorticity maps deduced from the wind fields for the region poleward of ∼−80°, which has been extensively covered over the last four years of observations. The cyclonic features related to the stable polar cyclones are embedded in a slightly, but diffused anticyclonic circulation, in which short‐living anticyclones emerge with respect to the surroundings. Although the general stability of both the cyclones and the whole system is strongly confirmed by this work, variations in the shape of the vortices, as well as changes in the local structures, have been observed.
Ensemble Representation of Satellite Precipitation Uncertainty Using a Nonstationary, Anisotropic Autocorrelation Model
Authors: Hartke Samantha H. , Wright Daniel B. , Li Zhe , Maggioni Viviana , Kirschbaum Dalia B. , Khan Sana 
Published: July 2022

AbstractThe usefulness of satellite multi‐sensor precipitation (SMP) and other satellite‐informed precipitation products in water resources modeling can be hindered by substantial errors which vary considerably with spatiotemporal scale. One approach to cope with these errors is to combine SMPs with ensemble generation methods, such that each ensemble member reflects one plausible realization of the true—but unknown—precipitation. This requires replicating the spatiotemporal autocorrelation structure of SMP errors. The climatology of this structure is unknown for most locations due to a lack of ground‐reference observations, while the unique anisotropy and nonstationarity within any particular precipitation system limit the relevance of this climatology to the depiction of individual storm systems. Characterizing and simulating autocorrelation across spatiotemporal scales has thus been called a grand challenge within the precipitation community. We introduce the Space‐Time Rainfall Error and Autocorrelation Model (STREAM), which combines uncalibrated, anisotropic and nonstationary SMP spatiotemporal correlation modeling with a pixel‐scale precipitation error model to stochastically generate ensemble precipitation fields that resemble “ground truth” precipitation. We generate STREAM precipitation ensembles at high resolution (1‐hr, 0.1°) and evaluate these ensembles at multiple scales. STREAM ensembles consistently bracket ground‐truth observations and replicate the autocorrelation structure of ground‐truth precipitation fields. STREAM is compatible with pixel‐scale error/uncertainty formulations beyond those presented here, and could be applied to other precipitation sources such as numerical weather predictions or blended products. Although ground truth is used here to parameterize pixel‐scale uncertainty, if combined with other recent work in SMP uncertainty characterization, STREAM could be used without any ground data.
Rock Abundance and Erosion Rate at the Zhurong Landing Site in Southern Utopia Planitia on Mars
Authors: Chen Zeyu , Wu Bo , Wang Yiran , Liu Shuo , Li Zhaojin , Yang Chenyu , Dong Jie , Rao Wei 
Published: July 2022

AbstractRocks on the Martian surface exhibit signatures of geological activities. Rock distribution is also an important factor for landing site selection for exploration missions. This study investigated the rock abundance and erosion rate at the landing site of the Chinese Mars rover, Zhurong, in southern Utopia Planitia. A convolutional neural network based method was developed for rock detection from the images (0.7 m/pixel) obtained by using the high‐resolution imaging camera (HiRIC) onboard the Tianwen‐1 orbiter. Approximately 10,000 rocks with a minimum diameter of 1.4 m (2 pixels on the image) were extracted from the HiRIC images covering the Zhurong landing site and its neighboring region. According to the results, the rock abundance at the Zhurong landing site was approximately 5%. Measurements from the ground images acquired by the Zhurong rover after landing confirmed a rock abundance of approximately 5% at the landing site, consistent with the orbital measurement before landing. Furthermore, we investigated the rock erosion rate at the Zhurong landing region. Rock abundance was negatively correlated with the crater retention age and positively correlated with crater diameter. The obtained rock breakdown rate (0.054 nm/y to 0.074 nm/y) and surface denudation rate by filled volume of craters (0.104 nm/y to 0.209 nm/y) were in agreement with the values previously reported for the Amazonian period on Mars. The low erosion rate implies a dry climate and the absence of fluvial erosion processes in the Amazonian period.
Mechanically Coupled Areas on the Plate Interface in the Nankai Trough, Japan and a Possible Seismic and Aseismic Rupture Scenario for Megathrust Earthquakes
Authors: Saito Tatsuhiko , Noda Akemi 
Published: July 2022

AbstractQuantifying the stress distribution or finding mechanically coupled areas on the plate interface is fundamentally important for conjecturing megathrust earthquakes that may occur in the future. Kinematically coupled areas, or slip deficit distributions, on plate interfaces were commonly estimated by geodetic‐data analyses. However, mechanically coupled areas are not identical to the kinematically coupled areas. The present study develops an inversion method to estimate the stress rate distribution as mechanically coupled areas. We apply this method to the Nankai trough subduction zone, southwestern Japan to detect mechanically coupled areas. Some of the estimated coupled areas correspond to the rupture areas of historical earthquakes. Others are in a deeper part, which may release the stress as aseismic slip. We then construct a rupture scenario that can occur in the Nankai trough in the future based on the estimated mechanical coupling, assuming that an effective stress accumulation period is 100 years. The scenario consists of a foreshock of MW 8.0 followed by an afterslip of MW 7.7 and a mainshock of MW 8.2. Although the moment magnitude of the afterslip is slightly smaller than the foreshock, the strain energy released by the foreshock is significantly larger than the afterslip. In order to compare events when the stress drops are significantly different, it is useful to use the minimum released strain energy, or available energy, to characterize the magnitude of the events.
Variability of Hydration Across the Southern Hemisphere of the Moon as Observed by Deep Impact
Authors: Laferriere K. L. , Sunshine J. M. , Feaga L. M. 
Published: July 2022

AbstractMeasurements of the 3 μm absorption feature, associated with the presence of hydroxyl and potentially molecular water, were first observed in 2009 by three separate spacecraft’ observations. Subsequent observations have revealed widespread but variable hydration over the sunlit regions of the Moon. The variability can help to disentangle the individual contributions of OH and H2O to the 3 μm absorption feature and provide insight into the mechanism of production and loss of OH/H2O on the lunar surface. We investigate the spatial and diurnal variations of hydration on the southern hemisphere of the Moon as observed by the Deep Impact spacecraft during the lunar flybys in 2009 at spatial scales of 30–70 km/pixel. For a subset of observations of across the lunar south polar region (∼2% of the lunar surface), repeat coverage includes three different times spanning half a lunar day, allowing for exploration of diurnal variability. We determine that OH/H2O is widespread but variable across the lunar south pole. At all but the lowest temperatures observed, highland regions have stronger hydration absorption features than the maria. Changes in band strength demonstrate variable loss rates controlled by surface temperatures with H2O lost quicker at higher temperatures. Observed variability in the band shape strongly suggests higher H2O abundance at low temperatures. These observations are strong evidence that the unique shape of the 3 μm band is due to both OH and H2O. The rapid diurnal evolution of the absorption feature implies that migration of these constituents occurs locally over short distances driven by temperature changes.
Reconstructing Sediment Transport by Migrating Bedforms in the Physical and Spectral Domains
Authors: Lee Jiyong , Singh Arvind , Guala Michele 
Published: July 2022

AbstractCharacteristics of migrating bedforms are often used to indirectly quantify the volumetric sediment flux in fluvial environments. Yet, the range of bedform scales that actually contribute to the sediment transport remains elusive. We performed a series of experiments under four different transport stages in a large‐scale sediment recirculating flume. Three independent variables were simultaneously measured: 2D spatio‐temporal bathymetry z(x, y, t), high frequency temporal bed elevations at fixed locations z(t), and temporal change of the sediment weight carried by migrating bedforms near the channel outlet qm(t). Both the measured spatio‐temporal bed evolution and the sediment discharge were analyzed using bedform tracking and Fourier decomposition. We found that small, rapidly migrating secondary bedforms emerge as a main contributor to the sediment transport and to the propagation of larger primary bedforms that slowly migrate underneath. This critical information allows us to define the range of transport‐contributing scales that must be accounted for in a scale‐dependent sediment mass flux model to enable the estimation of the total bedform transport from bed elevation time series.
Classifying Mixing Regimes in Ponds and Shallow Lakes
Authors: Holgerson Meredith A. , Richardson David C. , Roith Joseph , Bortolotti Lauren E. , Finlay Kerri , Hornbach Daniel J. , Gurung Kshitij , Ness Andrew , Andersen Mikkel R. , Bansal Sheel , Finlay Jacques C. , Cianci‐Gaskill Jacob A. , Hahn Shannon , Janke Benjamin D. , McDonald Cory , Mesman Jorrit P. , North Rebecca L. , Roberts Cassandra O. , Sweetman Jon N. , Webb Jackie R. 
Published: July 2022

AbstractLakes are classified by thermal mixing regimes, with shallow waterbodies historically categorized as continuously mixing systems. Yet, recent studies demonstrate extended summertime stratification in ponds, underscoring the need to reassess thermal classifications for shallow waterbodies. In this study, we examined the summertime thermal dynamics of 34 ponds and shallow lakes across temperate North America and Europe to categorize and identify the drivers of different mixing regimes. We identified three mixing regimes: rarely (n = 18), intermittently (n = 10), and often (n = 6) mixed, where waterbodies mixed an average of 2%, 26%, and 75% of the study period, respectively. Waterbodies in the often mixed category were larger (≥4.17 ha) and stratification weakened with increased wind shear stress, characteristic of “shallow lakes.” In contrast, smaller waterbodies, or “ponds,” mixed less frequently, and stratification strengthened with increased shortwave radiation. Shallow ponds (<0.74 m) mixed intermittently, with daytime stratification often breaking down overnight due to convective cooling. Ponds ≥0.74 m deep were rarely or never mixed, likely due to limited wind energy relative to the larger density gradients associated with slightly deeper water columns. Precipitation events weakened stratification, even causing short‐term mixing (hours to days) in some sites. By examining a broad set of shallow waterbodies, we show that mixing regimes are highly sensitive to very small differences in size and depth, with potential implications for ecological and biogeochemical processes. Ultimately, we propose a new framework to characterize the variable mixing regimes of ponds and shallow lakes.
Cardiac-specific overexpression of Ndufs1 ameliorates cardiac dysfunction after myocardial infarction by alleviating mitochondrial dysfunction and apoptosis
Authors: Qi Bingchao , Song Liqiang , Hu Lang , Guo Dong , Ren Gaotong , Peng Tingwei , Liu Mingchuan , Fang Yexian , Li Chunyu , Zhang Mingming , Li Yan 
Published: July 2022

AbstractMyocardial infarction (MI) is the leading cause of premature death among adults. Cardiomyocyte death and dysfunction of the remaining viable cardiomyocytes are the main pathological factors of heart failure after MI. Mitochondrial complexes are emerging as critical mediators for the regulation of cardiomyocyte function. However, the precise roles of mitochondrial complex subunits in heart failure after MI remain unclear. Here, we show that NADH:ubiquinone oxidoreductase core subunit S1 (Ndufs1) expression is decreased in the hearts of heart failure patients and mice with myocardial infarction. Furthermore, we found that cardiac-specific Ndufs1 overexpression alleviates cardiac dysfunction and myocardial fibrosis in the healing phase of MI. Our results demonstrated that Ndufs1 overexpression alleviates MI/hypoxia-induced ROS production and ROS-related apoptosis. Moreover, upregulation of Ndufs1 expression improved the reduced activity of complex I and impaired mitochondrial respiratory function caused by MI/hypoxia. Given that mitochondrial function and cardiomyocyte apoptosis are closely related to heart failure after MI, the results of this study suggest that targeting Ndufs1 may be a potential therapeutic strategy to improve cardiac function in patients with heart failure.
Hollow nanoparticles synthesized via Ostwald ripening and their upconversion luminescence-mediated Boltzmann thermometry over a wide temperature range
Authors: An Ran , Liang Yuan , Deng Ruiping , Lei Pengpeng , Zhang Hongjie 
Published: July 2022

AbstractUpconversion nanoparticles (UCNPs) with hollow structures exhibit many fascinating optical properties due to their special morphology. However, there are few reports on the exploration of hollow UCNPs and their optical applications, mainly because of the difficulty in constructing hollow structures by conventional methods. Here, we report a one-step template-free method to synthesize NaBiF4:Yb,Er (NBFYE) hollow UCNPs via Ostwald ripening under solvothermal conditions. Moreover, we also elucidate the possible formation mechanism of hollow nanoparticles (HNPs) by studying the growth process of nanoparticles in detail. By changing the contents of polyacrylic acid and H2O in the reaction system, the central cavity size of NBFYE nanoparticles can be adjusted. Benefiting from the structural characteristics of large internal surface area and high surface permeability, NBFYE HNPs exhibit excellent luminescence properties under 980 nm near-infrared irradiation. Importantly, NBFYE hollow UCNPs can act as self-referenced ratiometric luminescent thermometers under 980 nm laser irradiation, which are effective over a wide temperature range from 223 K to 548 K and have a maximum sensitivity value of 0.0065 K−1 at 514 K. Our work clearly demonstrates a novel method for synthesizing HNPs and develops their applications, which provides a new idea for constructing hollow structure UCNPs and will also encourage researchers to further explore the optical applications of hollow UCNPs.
Blocking glycine utilization inhibits multiple myeloma progression by disrupting glutathione balance
Authors: Xia Jiliang , Zhang Jingyu , Wu Xuan , Du Wanqing , Zhu Yinghong , Liu Xing , Liu Zhenhao , Meng Bin , Guo Jiaojiao , Yang Qin , Wang Yihui , Wang Qinglin , Feng Xiangling , Xie Guoxiang , Shen Yi , He Yanjuan , Xiang Juanjuan , Wu Minghua , An Gang , Qiu Lugui , Jia Wei , Zhou Wen 
Published: July 2022

AbstractMetabolites in the tumor microenvironment are a critical factor for tumor progression. However, the lack of knowledge about the metabolic profile in the bone marrow (BM) microenvironment of multiple myeloma (MM) limits our understanding of MM progression. Here, we show that the glycine concentration in the BM microenvironment is elevated due to bone collagen degradation mediated by MM cell-secreted matrix metallopeptidase 13 (MMP13), while the elevated glycine level is linked to MM progression. MM cells utilize the channel protein solute carrier family 6 member 9 (SLC6A9) to absorb extrinsic glycine subsequently involved in the synthesis of glutathione (GSH) and purines. Inhibiting glycine utilization via SLC6A9 knockdown or the treatment with betaine suppresses MM cell proliferation and enhances the effects of bortezomib on MM cells. Together, we identify glycine as a key metabolic regulator of MM, unveil molecular mechanisms governing MM progression, and provide a promising therapeutic strategy for MM treatment.
Machine learning-based tissue of origin classification for cancer of unknown primary diagnostics using genome-wide mutation features
Authors: Nguyen Luan , Van Hoeck Arne , Cuppen Edwin 
Published: July 2022

AbstractCancers of unknown primary (CUP) origin account for ∼3% of all cancer diagnoses, whereby the tumor tissue of origin (TOO) cannot be determined. Using a uniformly processed dataset encompassing 6756 whole-genome sequenced primary and metastatic tumors, we develop Cancer of Unknown Primary Location Resolver (CUPLR), a random forest TOO classifier that employs 511 features based on simple and complex somatic driver and passenger mutations. CUPLR distinguishes 35 cancer (sub)types with ∼90% recall and ∼90% precision based on cross-validation and test set predictions. We find that structural variant derived features increase the performance and utility for classifying specific cancer types. With CUPLR, we could determine the TOO for 82/141 (58%) of CUP patients. Although CUPLR is based on machine learning, it provides a human interpretable graphical report with detailed feature explanations. The comprehensive output of CUPLR complements existing histopathological procedures and can enable improved diagnostics for CUP patients.