bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geomorphological Controls on Groundwater Transit Times: A Synthetic Analysis at the Hillslope Scale
Authors: Gauvain Alexandre , Leray Sarah , Marçais Jean , Roques Clément , Vautier Camille , Gresselin Frédéric , Aquilina Luc , de Dreuzy Jean‐Raynald 
Published: July 2021

AbstractWe investigated how geomorphological structures shape Transit Time Distributions (TTDs) in shallow aquifers. Extensive three‐dimensional simulations were performed to determine the TTDs for synthetic convergent, straight, and divergent hillslopes with a constant slope. The uniform recharge applied on top of the aquifer is transferred to the receiving stream through steady‐state groundwater flows, return flows and saturation excess overland flows. Without seepage, TTDs evolve from uniform‐ to power law‐like‐ distributions depending on the average distance of the groundwater volume to the river (barycenter). Remarkably, the coefficient of variation (ratio of the standard deviation to the mean) of the TTDs scales linearly with the barycenter in agreement with a theoretical prediction based on three analytical approximations derived for specific cases. With seepage, the TTD has three separate modes corresponding to rapid saturation excess overland flows, to the intermediate flow paths ending in seepage area and to the slower flow paths going all the way to a discharge in the river. The coefficient of variation additionally depends on the extent of the seepage area. For a natural hillslope in the crystalline basement of Normandy (France), the same synthetic analysis demonstrates that the coefficient of variation is not only determined by the extent of the seepage zone but also by its structure in relation to the local and global geomorphological organization. The results suggest the possibility to assess the variability of transit times by combining geomorphological analysis, surface soil saturation observations and environmental tracers.
Global Cooling Hiatus Driven by an AMOC Overshoot in a Carbon Dioxide Removal Scenario
Authors: An Soon‐Il , Shin Jongsoo , Yeh Sang‐Wook , Son Seok‐Woo , Kug Jong‐Seong , Min Seung‐Ki , Kim Hyo‐Jeong 
Published: July 2021

AbstractThe reversibility of global mean surface temperature was examined by a transient CO2 reversibility experiment using an Earth system model. The results showed that after CO2 ramp‐up toward CO2 quadrupling and ramp‐down returned to the present‐day level, the global mean surface temperature kept decreasing but stopped to change for ∼40 years in the early net‐zero CO2 emission period. This period, referred to a cooling hiatus, resulted from a compensation between Southern Hemisphere cooling and Northern Hemisphere warming. The Northern Hemisphere warming was centered over the North Atlantic. This localized warming was caused by an excessive heat advection by a delayed and surpassed Atlantic Meridional Overturning Circulation (AMOC) to CO2 forcing. During the progression of CO2 change, the meridional salinity gradient between subtropic and subpolar regions was enhanced, and the oceanic stratification in subpolar North Atlantic was reduced due to accumulated heat and reduced vertical salt import in the deeper ocean. As AMOC started to recover, consequently, the enhanced salt advection feedback and the relaxed buoyant force resulted in AMOC overshoot.
Convection‐Permitting Hindcasting of Diurnal Variation of Mei‐yu Rainfall Over East China With a Global Variable‐Resolution Model
Authors: Xu Mingyue , Zhao Chun , Gu Jun , Feng Jiawang , Hagos Samson , Leung L. Ruby , Luo Yali , Guo Jianping , Li Rui , Fu Yunfei 
Published: July 2021

AbstractTwo sets of 48‐h hindcast experiments for Mei‐yu season using non‐hydrostatic global variable‐resolution model (MPAS‐Atmosphere) with regional refinement at 4 km resolution (V4km) and uniform 60 km resolution (U60km) are first‐time conducted to attempt at simulating the Mei‐yu rainfall in 2015 over East China. The analysis focuses on the seasonal average of diurnal variation of precipitation amount (PA), intensity (PI), and frequency (PF). Both simulations reasonably reproduce the spatial distribution of PA. V4km is more skillful in simulating the spatial distributions and magnitudes of PF and PI. The diurnal cycle of Mei‐yu rainfall shows a major early morning peak and a minor afternoon peak, contributed by precipitation during two sub‐periods with distinct synoptic circulations. With strong Mei‐yu in the first sub‐period, the diurnal variation of PA is controlled by nocturnal southwesterly jet. V4km overestimates the morning peak mainly due to its bias in simulating boundary layer inertial oscillation. Although differences in PA between the simulations are small, U60km overestimates PF and underestimates PI. With weak Mei‐yu in the second sub‐period, the diurnal variation of PA is controlled by both synoptic circulation and local convection. At both resolutions, deviations in the large‐scale circulation modulated by a few typhoons lead to positive biases in the morning peak of PA. After removing the typhoon impacts, V4km captures the observed diurnal cycle of PA well, while U60km significantly underestimates PA and PI particularly in the afternoon. Future studies focusing on advancing modeling of southwesterly jet and typhoons may further improve convection permitting simulation of Mei‐yu rainfall.
Atmospheric CO2 Exchange of a Small Mountain Lake: Limitations of Eddy Covariance and Boundary Layer Modeling Methods in Complex Terrain
Authors: Scholz K. , Ejarque E. , Hammerle A. , Kainz M. , Schelker J. , Wohlfahrt G. 
Published: July 2021

AbstractLakes receive and transform significant amounts of terrestrial carbon and are often considered a source of atmospheric carbon dioxide (CO2). Yet, continuous direct measurements of lake‐atmosphere CO2 exchange with high temporal resolution are sparse. In this study, we measured the CO2 exchange of a mountain lake in the eastern Austrian Alps continuously for one year using the eddy covariance (EC) and the boundary layer model (BLM) approaches. Results from both the EC and the BLM methods indicated the lake to be a small source of atmospheric CO2 with highest emissions in fall. EC flux measurements were affected by low‐frequency contributions especially during low wind conditions. The CO2 concentration gradient at the air‐water interface decreased during night‐time due to an increase in atmospheric CO2 above the lake, likely caused by cold and CO2‐rich air draining from the surrounding land. Consequently, BLM fluxes were lower during night‐time than during daytime. This diel pattern was lacking in the EC flux measurements because the EC instruments deployed at the shore of the lake did not capture low nocturnal lake CO2 fluxes due to the local wind regime. Overall, this study illustrates the effect of the surrounding landscape on lake‐atmosphere flux measurements. We conclude that estimating CO2 evasion from lakes situated in complex topography needs to explicitly account for biases in EC flux measurements caused by low‐frequency contributions and local wind regimes.
An Experimental and Numerical Approach to Modeling Large Wood Displacement in Rivers
Authors: Panici D. 
Published: July 2021

AbstractLarge wood (LW) is used for river restoration, aquatic habitat conservation, and flood control; however, it can pose a threat to human life and the built environment. The formation of LW jams, river management strategies, and design of mitigation measures crucially all depend on how the large wood is transported along a river. This paper experimentally analyses at laboratory scale the motion of natural sticks in a long stretch of a straight channel (16 m), when LW is released at different locations and with different flow conditions. Results show that instream large wood, following a transient motion shortly after being released at the water surface, tends to follow preferential patterns along the channel. Froude number and location of large wood input may provide an estimation of the LW location in downstream reaches. Several mechanisms of motion were observed, some of which were very common, including a frequent tendency to assume a tilted position with respect to the direction parallel to the flow. The experiments also suggest that theories on secondary cells responsible for channeling LW in preferential directions are incomplete. A new model, based on acceleration induced by hydrodynamic actions, has been established and proposed in this work, showing promising results and paving the way for the development of a comprehensive model for transport of large wood at the river surface in full‐scale applications.
Exosomal annexin A6 induces gemcitabine resistance by inhibiting ubiquitination and degradation of EGFR in triple-negative breast cancer
Authors: Li Ting , Tao Zhonghua , Zhu Yihui , Liu Xiaojia , Wang Leiping , Du Yiqun , Cao Jun , Wang Biyun , Zhang Jian , Hu Xichun 
Published: July 2021

AbstractExosomes are carriers of intercellular information that regulate the tumor microenvironment, and they have an essential role in drug resistance through various mechanisms such as transporting RNA molecules and proteins. Nevertheless, their effects on gemcitabine resistance in triple-negative breast cancer (TNBC) are unclear. In the present study, we examined the effects of exosomes on TNBC cell viability, colony formation, apoptosis, and annexin A6 (ANXA6)/EGFR expression. We addressed their roles in gemcitabine resistance and the underlying mechanism. Our results revealed that exosomes derived from resistant cancer cells improved cell viability and colony formation and inhibited apoptosis in sensitive cancer cells. The underlying mechanism included the transfer of exosomal ANXA6 from resistant cancer cells to sensitive cancer cells. Isobaric peptide labeling–liquid chromatography–tandem mass spectrometry and western blotting revealed that ANXA6 was upregulated in resistant cancer cells and their derived exosomes. Sensitive cancer cells exhibited resistance with increased viability and colony formation and decreased apoptosis when ANXA6 was stably overexpressed. On the contrary, knockdown ANXA6 restored the sensitivity of cells to gemcitabine. Co-immunoprecipitation expression and GST pulldown assay demonstrated that exosomal ANXA6 and EGFR could interact with each other and exosomal ANXA6 was associated with the suppression of EGFR ubiquitination and downregulation. While adding lapatinib reversed gemcitabine resistance induced by exosomal ANXA6. Moreover, ANXA6 and EGFR protein expression was correlated in TNBC tissues, and exosomal ANXA6 levels at baseline were lower in patients with highly sensitive TNBC than those with resistant TNBC when treated with first-line gemcitabine-based chemotherapy. In conclusion, resistant cancer cell-derived exosomes induced gemcitabine resistance via exosomal ANXA6, which was associated with the inhibition of EGFR ubiquitination and degradation. Exosomal ANXA6 levels in the serum of patients with TNBC might be predictive of the response to gemcitabine-based chemotherapy.
Implication of human endogenous retrovirus W family envelope in hepatocellular carcinoma promotes MEK/ERK-mediated metastatic invasiveness and doxorubicin resistance
Authors: Zhou Yan , Liu Lijuan , Liu Youyi , Zhou Ping , Yan Qiujin , Yu Honglian , Chen Xiaobei , Zhu Fan 
Published: July 2021

AbstractHuman endogenous retrovirus (HERVs), originating from exogenous retroviral infections of germ cells millions of years ago, have the potential for human diseases. Syncytin-1, an envelope protein encoded by the HERV W family, participates in the contexts of schizophrenia, multiple sclerosis, diabetes, and several types of cancers. Nevertheless, there is no report on the expression pattern and potential mechanism of Syncytin-1 in HCC. Here we found Syncytin-1 expression was up-regulated in HCC compared to adjacent non-tumorous tissues, especially in advanced HCC. Syncytin-1 was an independent risk factor to predict vascular invasion, metastasis, larger tumor size, and poor prognosis in HCC patients. Further analysis discovered that Syncytin-1 overexpression positively associated with HCC patients with serum HBsAg positive. Functional experiments in vitro and in vivo demonstrated that Syncytin-1 enhanced cell proliferation, metastasis, and tumorigenicity in HCC. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis suggested that the mitogen-activated protein kinase (MEK)/extracellular signal-regulated protein kinase (ERK) pathway was involved in HCC. Our clinical data indicated that the levels of phosphorylation MEK1/2 and ERK1/2 were increased in HCC comparing with adjacent non-tumorous tissues. It showed the linear correlation between Syncytin-1 expression and upregulated MEK1/2 and ERK1/2 phosphorylation levels in HCC. Furthermore, Syncytin-1 activated MEK/ERK pathway in HCC cells. In-depth research showed that the inflammation-activated MEK/ERK pathway was essential in Syncytin-1 promoted hepatocarcinogenesis. Syncytin-1 suppressed doxorubicin-induced apoptosis via MEK/ERK cascade. In conclusion, Syncytin-1 promoted HCC progression and doxorubicin resistance via the inflammation-activated MEK/ERK pathway. Our findings revealed that Syncytin-1 was a potential prognostic biomarker and therapeutic target for HCC.
Delineating spatiotemporal and hierarchical development of human fetal innate lymphoid cells
Authors: Liu Chen , Gong Yandong , Zhang Han , Yang Hua , Zeng Yang , Bian Zhilei , Xin Qian , Bai Zhijie , Zhang Man , He Jian , Yan Jing , Zhou Jie , Li Zongcheng , Ni Yanli , Wen Aiqing , Lan Yu , Hu Hongbo , Liu Bing 
Published: July 2021

AbstractWhereas the critical roles of innate lymphoid cells (ILCs) in adult are increasingly appreciated, their developmental hierarchy in early human fetus remains largely elusive. In this study, we sorted human hematopoietic stem/progenitor cells, lymphoid progenitors, putative ILC progenitor/precursors and mature ILCs in the fetal hematopoietic, lymphoid and non-lymphoid tissues, from 8 to 12 post-conception weeks, for single-cell RNA-sequencing, followed by computational analysis and functional validation at bulk and single-cell levels. We delineated the early phase of ILC lineage commitment from hematopoietic stem/progenitor cells, which mainly occurred in fetal liver and intestine. We further unveiled interleukin-3 receptor as a surface marker for the lymphoid progenitors in fetal liver with T, B, ILC and myeloid potentials, while IL-3RA– lymphoid progenitors were predominantly B-lineage committed. Notably, we determined the heterogeneity and tissue distribution of each ILC subpopulation, revealing the proliferating characteristics shared by the precursors of each ILC subtype. Additionally, a novel unconventional ILC2 subpopulation (CRTH2– CCR9+ ILC2) was identified in fetal thymus. Taken together, our study illuminates the precise cellular and molecular features underlying the stepwise formation of human fetal ILC hierarchy with remarkable spatiotemporal heterogeneity.
Parkinson’s disease multimodal imaging: F-DOPA PET, neuromelanin-sensitive and quantitative iron-sensitive MRI
Authors: Depierreux Frédérique , Parmentier Eric , Mackels Laurane , Baquero Katherine , Degueldre Christian , Balteau Evelyne , Salmon Eric , Phillips Christophe , Bahri Mohamed Ali , Maquet Pierre , Garraux Gaëtan 
Published: July 2021

AbstractParkinson’s disease (PD) is a neurodegenerative synucleinopathy characterized by the degeneration of neuromelanin (NM)-containing dopaminergic neurons and deposition of iron in the substantia nigra (SN). How regional NM loss and iron accumulation within specific areas of SN relate to nigro-striatal dysfunction needs to be clarified. We measured dopaminergic function in pre- and postcommissural putamen by [18F]DOPA PET in 23 Parkinson’s disease patients and 23 healthy control (HC) participants in whom NM content and iron load were assessed in medial and lateral SN, respectively, by NM-sensitive and quantitative R2* MRI. Data analysis consisted of voxelwise regressions testing the group effect and its interaction with NM or iron signals. In PD patients, R2* was selectively increased in left lateral SN as compared to healthy participants, suggesting a local accumulation of iron in Parkinson’s disease. By contrast, NM signal differed between PD and HC, without specific regional specificity within SN. Dopaminergic function in posterior putamen decreased as R2* increased in lateral SN, indicating that dopaminergic function impairment progresses with iron accumulation in the SN. Dopaminergic function was also positively correlated with NM signal in lateral SN, indicating that dopaminergic function impairment progresses with depigmentation in the SN. A complex relationship was detected between R2* in the lateral SN and NM signal in the medial SN. In conclusion, multimodal imaging reveals regionally specific relationships between iron accumulation and depigmentation within the SN of Parkinson’s disease and provides in vivo insights in its neuropathology.
BiPSim: a flexible and generic stochastic simulator for polymerization processes
Authors: Fischer Stephan , Dinh Marc , Henry Vincent , Robert Philippe , Goelzer Anne , Fromion Vincent 
Published: July 2021

AbstractDetailed whole-cell modeling requires an integration of heterogeneous cell processes having different modeling formalisms, for which whole-cell simulation could remain tractable. Here, we introduce BiPSim, an open-source stochastic simulator of template-based polymerization processes, such as replication, transcription and translation. BiPSim combines an efficient abstract representation of reactions and a constant-time implementation of the Gillespie’s Stochastic Simulation Algorithm (SSA) with respect to reactions, which makes it highly efficient to simulate large-scale polymerization processes stochastically. Moreover, multi-level descriptions of polymerization processes can be handled simultaneously, allowing the user to tune a trade-off between simulation speed and model granularity. We evaluated the performance of BiPSim by simulating genome-wide gene expression in bacteria for multiple levels of granularity. Finally, since no cell-type specific information is hard-coded in the simulator, models can easily be adapted to other organismal species. We expect that BiPSim should open new perspectives for the genome-wide simulation of stochastic phenomena in biology.
Temperature stress and disease drives the extirpation of the threatened pillar coral, Dendrogyra cylindrus, in southeast Florida
Authors: Jones Nicholas P. , Kabay Lystina , Semon Lunz Kathleen , Gilliam David S. 
Published: July 2021

AbstractRare species population dynamics can elucidate the resilience of an ecosystem. On coral reefs, climate change and local anthropogenic stressors are threatening stony coral persistence, increasing the need to assess vulnerable species locally. Here, we monitored the threatened pillar coral, Dendrogyra cylindrus, population in southeast Florida, USA, in relation to consecutive heat stress events in 2014 and 2015. In the fall of each year, D. cylindrus colonies bleached following intense thermal stress and by June 2020 all monitored colonies died from a white-syndrome type disease. This resulted in the ecological extinction of D. cylindrus in the Southeast Florida Coral Reef Ecosystem Conservation Area (ECA). White-syndrome type disease was first seen in February 2014 on four colonies (19% prevalence) near the major international port, Port Everglades and disease prevalence peaked in fall 2015 (58%). Disease prevalence increased with maximum water temperature, while disease related mortality increased with mean water temperature. Our findings suggest that thermal stress exacerbated underlying stony coral disease, resulting in an outbreak contributing to the ecological extirpation of D. cylindrus in the ECA. We suggest that stony coral resilience is severely compromised by chronic environmental disturbance which hinders community recovery.
Silver incorporated into g-C3N4/Alginate as an efficient and heterogeneous catalyst for promoting click and A3 and KA2 coupling reaction
Authors: Daraie Mansoureh , Heravi Majid M. , Mohammadi Pourya , Daraie Ali 
Published: July 2021

AbstractFe3O4/g-C3N4/Alginate-Ag nanocomposite as a novel and effective nanocatalyst was successfully prepared. This nanocomposite was fully characterized using several techniques such as X‐ray diffraction (XRD), field emission scanning electron microscopy with energy dispersive spectroscopy (FESEM-EDS), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR). In addition, the catalytic activity of this novel and characterized nanocatalyst was investigated in the regioselective synthesis of 1,4-disubstituted 1,2,3-triazoles via click reaction and A3 and KA2 coupling reaction in aqueous media. The prepared nanocatalyst was simply recovered by using an external magnet and reused for several times with a slight loss of catalytic activity.
Evolution of the prevalence of obesity in the adult population in France, 2013–2016: the Constances study
Authors: Czernichow Sébastien , Renuy Adeline , Rives-Lange Claire , Carette Claire , Airagnes Guillaume , Wiernik Emmanuel , Ozguler Anna , Kab Sofiane , Goldberg Marcel , Zins Marie , Matta Joane 
Published: July 2021

AbstractThis study provides trends in obesity prevalence in adults from 2013 to 2016 in France. 63,582 men and women from independent samples upon inclusion from the Constances cohort were included. Anthropometrics were measured at Health Screening Centers and obesity defined as a Body mass index (BMI) ≥ 30 kg/m2; obesity classes according to BMI are as follows: class 1 [30–34.9]; class 2 [35–39.9]; class 3 [≥ 40 kg/m2]. Linear trends across obesity classes by sex and age groups were examined in regression models and percentage point change from 2013 to 2016 for each age category calculated. All analyses accounted for sample weights for non-response, age and sex-calibrated to the French population. Prevalence of obesity ranged from 14.2 to 15.2% and from 14 to 15.3% in women and men respectively from 2013 to 2016. Class 1 obesity category prevalence was the only one to increase significantly across survey years in both men and women (p for linear trend = 0.04 and 0.01 in women and men respectively). The only significant increase for obesity was observed in the age group 18–29 y in both women and men (+ 2.71% and + 3.26% point increase respectively, equivalent to an approximate rise of 50% in women and 93% in men, p = 0.03 and 0.02 respectively). After adjustment for survey non-response and for age and sex distribution, the results show that class 1 obesity prevalence has significantly increased in both women and men from 2013 to 2016, and only in young adults in a representative sample of the French population aged 18–69 years old.