bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Betti number of the path homology of random directed graphs
Authors: Chaplin Thomas 
Published: December 2022

AbstractPath homology is a topological invariant for directed graphs, which is sensitive to their asymmetry and can discern between digraphs which are indistinguishable to the directed flag complex. In Erdős–Rényi directed random graphs, the first Betti number undergoes two distinct transitions, appearing at a low-density boundary and vanishing again at a high-density boundary. Through a novel, combinatorial condition for digraphs we describe both sparse and dense regimes under which the first Betti number of path homology is zero with high probability. We combine results of Grigor’yan et al., regarding generators for chain groups, with methods of Kahle and Meckes in order to determine regimes under which the first Betti number is positive with high probability. Together, these results describe the gradient of the lower boundary and yield bounds for the gradient of the upper boundary. With a view towards hypothesis testing, we obtain tighter bounds on the probability of observing a positive first Betti number in a high-density digraph of finite size. For comparison, we apply these techniques to the directed flag complex and derive analogous results
Platelets in COVID-19 disease: friend, foe, or both?
Authors: Smęda Marta , Hosseinzadeh Maleki Ebrahim , Pełesz Agnieszka , Chłopicki Stefan 
Published: December 2022

AbstractImmuno-thrombosis of COVID-19 results in the activation of platelets and coagulopathy. Antiplatelet therapy has been widely used in COVID-19 patients to prevent thrombotic events. However, recent analysis of clinical trials does not support the major effects of antiplatelet therapy on mortality in hospitalized COVID-19 patients, despite the indisputable evidence for an increased risk of thrombotic complications in COVID-19 disease. This apparent paradox calls for an explanation. Platelets have an important role in sensing and orchestrating host response to infection, and several platelet functions related to host defense response not directly related to their well-known hemostatic function are emerging. In this paper, we aim to review the evidence supporting the notion that platelets have protective properties in maintaining endothelial barrier integrity in the course of an inflammatory response, and this role seems to be of particular importance in the lung. It might, thus, well be that the inhibition of platelet function, if affecting the protective aspect of platelet activity, might diminish clinical benefits resulting from the inhibition of the pro-thrombotic phenotype of platelets in immuno-thrombosis of COVID-19. A better understanding of the platelet-dependent mechanisms involved in the preservation of the endothelial barrier is necessary to design the antiplatelet therapeutic strategies that inhibit the pro-thrombotic activity of platelets without effects on the vaso-protective function of platelets safeguarding the pulmonary endothelial barrier during multicellular host defense in pulmonary circulation.
Respectful maternity care in the UK using a decolonial lens
Authors: Lokugamage Amali U. , Robinson Nathan , Pathberiya Sithira D. C. , Wong Sarah , Douglass Christine 
Published: December 2022

AbstractRespectful maternity care (RMC) is part of a global movement addressing the previous absence of human rights in global safe maternal care guidance. RMC is grounded in kindness, compassion, dignity and respectful working conditions. The decolonisation movement in healthcare seeks to dismantle structural biases set up from a historically white, male, heteronormative Eurocentric medical system. This article applies a decolonising lens to the RMC agenda and examines barriers to its implementation in UK healthcare systems. Searches of peer-reviewed journals about decolonising maternity care in the UK revealed little. Drawing from wider information bases, we examine power imbalances constructed throughout a history of various colonial biases yet lingering in maternity care. The overarching findings of our analysis revealed 3 areas of focus: professional structures and institutional biases; power imbalances between types of staff and stakeholders of care; and person-centred care through a decolonial lens. To uproot inequity and create fairer and more respectful maternity care for women, birthing people and staff, it is vital that contemporary maternity institutions understand the decolonial perspective. This novel enquiry offers a scaffolding to undertake this process. Due to significant differences in colonial history between Western colonising powers, it is important to decolonise with respect to these different territories, histories and challenges.
Use of Indices on Daily Timescales to Study Changes in Extreme Precipitation Across Nepal Over 40 Years (1976–2015)
Authors: Maharjan Manisha , Yoneda Minoru , Talchabhadel Rocky , Thapa Bhesh Raj , Aryal Anil 
Published: December 2022

AbstractThis paper presents a comprehensive picture of extreme precipitation across Nepal from 1976 to 2015 based on high‐quality daily precipitation observations from 28 precipitation stations spatially distributed across the country. We computed 11 extreme precipitation indices. The selected indices allow the analysis of extreme events (such as flood/inundation) related to heavy precipitation and evaluate the linkage with indications of agricultural production and drought (such as consecutive dry and wet days). Using a simple daily intensity index (SDII) and the number of days with daily precipitation ≥10 mm (R10), along with the total amount of annual precipitation (PRCPTOT), we summarized the distribution of the wet periods of the year at different locations. We divided the study period into two halves (T1: 1976–1995 and T2: 1996–2015) to examine the temporal mean, trends, and their shift. We emphasized the changes in those indices between these two periods across the country. Our results show that although the amount of precipitation (in terms of PRCPTOT and SDII) did not change significantly between the two periods (i.e., T1 and T2), there exists a clearly increasing trend of extreme precipitation indices in T2 compared to T1. In addition, the consecutive dry days show the rising tendency of elongated dry spells that can adversely affect plant/crop growth in the future. Our study recommends the need for effective management of both precipitation extremes (i.e., drier and wetter), for instance, by introducing irrigation facilities and flood mitigation measures.
Using Ensemble Meteorological Data Sets to Treat Meteorological Uncertainties in a Bayesian Volcanic Ash Inverse Modeling System: A Case Study, Grímsvötn 2011
Authors: Webster Helen N. , Thomson David J. 
Published: December 2022

AbstractAtmospheric dispersion models are employed in forecasting the atmospheric transport of ash clouds following a volcanic eruption. Errors in input meteorological data can, however, lead to discrepancies between the modeled and observed ash cloud locations. Furthermore, meteorological errors can affect the performance of inversion techniques used to estimate ash emissions. This study explores using ensemble meteorological data sets to overcome issues with meteorological errors in a Bayesian inversion system, Inversion Technique for Emissions Modelling (InTEM) for volcanic ash. Two measures (the evidence value and a cost function) are obtained from the Bayesian framework, and each measure is used to select a “best” meteorological data set from within the ensemble. These two best meteorological data sets are constructed in an iterative manner which is ideally suited for operational use when ash cloud forecasts are updated at regular intervals. The method is applied to the 2011 eruption of the Icelandic volcano Grímsvötn and improvements to ash cloud forecasts using the best meteorological data sets assessed. In this case study, errors in the deterministic meteorological data are significant, resulting in a reduction of ash emissions estimated by InTEM for volcanic ash. We also illustrate how the best meteorological data sets lead to more accurate modeling of the ash cloud.
Arctic Troposphere Warming Driven by External Radiative Forcing and Modulated by the Pacific and Atlantic
Authors: Suo Lingling , Gao Yongqi , Gastineau Guillaume , Liang Yu‐Chiao , Ghosh Rohit , Tian Tian , Zhang Ying , Kwon Young‐Oh , Matei Daniela , Otterå Odd Helge , Yang Shuting 
Published: December 2022

AbstractDuring the past decades, the Arctic has experienced significant tropospheric warming, with varying decadal warming rates. However, the relative contributions from potential drivers and modulators of the warming are yet to be further quantified. Here, we utilize a unique set of multi‐model large‐ensemble atmospheric simulations to isolate the respective contributions from the combined external radiative forcing (ERF‐AL), interdecadal Pacific variability (IPV), Atlantic multidecadal variability (AMV), and Arctic sea‐ice concentration changes (ASIC) to the warming during 1979–2013. In this study, the ERF‐AL impacts are the ERF impacts directly on the atmosphere and land surface, excluding the indirect effects through SST and SIC feedback. The ERF‐AL is the primary driver of the April–September tropospheric warming during 1979–2013, and its warming effects vary at decadal time scales. The IPV and AMV intensify the warming during their transitioning periods to positive phases and dampen the warming during their transitioning periods to negative phases. The IPV impacts are prominent in winter and spring and are stronger than AMV impacts on 1979–2013 temperature trends. The warming impacts of ASIC are generally restricted to below 700 hPa and are strongest in autumn and winter. The combined effects of these factors reproduce the observed accelerated and step‐down Arctic warming in different decades, but the intensities of the reproduced decadal variations are generally weaker than in the observed.
Persistence or Transition of the North Atlantic Oscillation Across Boreal Winter: Role of the North Atlantic Air‐Sea Coupling
Authors: Wu Renguang , Dai Panxi , Chen Shangfeng 
Published: December 2022

AbstractClimate anomalies over North America and Europe are closely related to the North Atlantic Oscillation (NAO). The persistence, decay or switch of the NAO phase across the boreal winter determines whether the NAO‐related climate anomalies are sustained, weakened or reversed during the boreal winter. This study compares the spatiotemporal evolution of atmospheric wind and sea surface temperature (SST) anomalies over the North Atlantic corresponding to persistence and switch of the NAO phase across the boreal winter. It is revealed that the persistence of the NAO from early to late winter is associated with a strong coupling between the NAO and the North Atlantic tripole SST anomalies. The formation of the tripole SST anomalies is attributed to the wind‐related surface latent heat flux changes. The tripole SST anomalies feedback on the NAO through eddy‐mean flow interaction. In contrast, during the winters with the switch of the NAO phase, the North Atlantic SST anomalies follow the wind changes, but do not have obvious feedback on the NAO. Our analysis identifies a prominent change of the winter NAO evolution in the early 1990s. The NAO switches its phase from early to late winter during 1970s through the early 1990s, but tends to maintain its phase during the boreal winter after the early 1990s. This interdecadal change appears to be related to the mean SST change. The SST increase in both the tropical and mid‐latitude North Atlantic Ocean in the early 1990s enhances the feedback of the NAO‐induced tripole SST anomalies on the NAO.
Intricate Regolith Reworking Processes Revealed by Microstructures on Lunar Impact Glasses
Authors: Yan Pan , Xiao Zhiyong , Wu Yunhua , Yang Wei , Li Jin‐Hua , Gu Li‐Xin , Liao Shiyong , Yin Zongjun , Wang Hao , Tian Heng‐Ci , Zhang Chi , Wu Suping , Ma Hong‐Xia , Tang Xu , Wu Shi‐Tou , Hui Hejiu , Xu Yuchen , Hsu Weibiao , Li Qiu‐Li , Luo Fanglu , Liu Yang , Li Xian‐Hua 
Published: December 2022

AbstractGlasses cooled from impact melt and vapor are a common component in lunar regolith, carrying important information about protolith composition, regolith formation, and impact flux on the Moon. Interpretations, however, are frequently challenged due to widespread ambiguity in determining their provenances. Regolith samples returned by China's Chang’E‐5 mission provide a unique opportunity to study the microscopic mechanism of regolith reworking on the Moon, because as evidenced by the coherent radioisotope ages and petrographic characteristics of basaltic clasts in the regolith, the Chang’E‐5 regolith was mainly evolved from local mare materials, containing minor exotic components. Here, we report 153 glass particles larger than 20 μm in diameters that were screened from 500 mg of Chang’E‐5 regolith. Most glass particles have rotational shapes and contain structural and/or compositional heterogeneities in interiors, and geochemical analyses reveal a dominant origin as impact melt of local mare materials. Surfaces of the impact glasses are observed to have abundant protruded and dented microstructures, which are classified as different groups based on their morphology and geochemistry. Similar microstructures were observed on impact spherules collected by the Apollo and Luna missions, but those on the Chang’E‐5 impact glasses were formed without substantial involvement of exotic ejecta. Microstructures such as silicate melt pancakes that frequently exhibit flow spikes at margins, nano‐phase iron‐rich mounds that are arranged with semi‐equidistant spaces in curves and patches, spatially clustered microcraters that are indicative of secondary impacts, and blunt linear scratches with terminal particles all suggest that regolith reworking mainly occurred among local materials at low speeds.
How Do Sky Conditions Affect the Relationships Between Ground‐Based Solar‐Induced Chlorophyll Fluorescence and Gross Primary Productivity Across Different Plant Types?
Authors: Wu Yunfei , Zhang Zhaoying , Zhang Xiaokang , Wu Linsheng , Zhang Yongguang 
Published: December 2022

AbstractSolar‐induced chlorophyll fluorescence (SIF) has been used as a proxy for gross primary productivity (GPP) estimations. However, knowledge on how links between SIF and GPP across different plant types vary in response to sky conditions remain unclear. Here, we investigated the effects of sky conditions on the GPP‐SIF relationship based on continuous measurements of SIF and flux across four different plant types. Our analysis shows that the GPP‐SIF links are affected by sky conditions and these linking patterns respond differently across plant types. We propose that the inconsistent responses of SIF and GPP to sky conditions are primarily driven by variations in light use efficiency (LUE = GPP/absorbed photosynthetic active radiation (APAR)). Furthermore, we explore a quantitative variation in LUE and SIFyield (SIF/APAR) separately via a decoupling of clearness index (CI) and photosynthetic active radiation under different sky conditions. LUE is more sensitive to sky conditions for the C3 plants (Forest, Wheat and Rice) than the C4 plant (Maize), and SIFyield shows more sensitivity to sky conditions for the forest than croplands. Due to the tight link between CI and other environmental factors, the incorporation of CI into the SIF‐based GPP model improves GPP estimates for all C3 plants at both instantaneous and daily scales. Our study implies that a consideration of sky conditions into the SIF‐based GPP model can significantly advance the GPP modeling under all sky conditions.
Spatio‐Temporal Variations in Carbon Isotope Discrimination Predicted by the JULES Land Surface Model
Authors: Palmer Lewis , Robertson Iain , Lavergne Aliénor , Hemming Deborah , Loader Neil J. , Young Giles , Davies Darren , Rinne‐Garmston Katja , Los Sietse , Williams Jamie 
Published: December 2022

AbstractStable carbon isotopes in plants can help evaluate and improve the representation of carbon and water cycles in land‐surface models, increasing confidence in projections of vegetation response to climate change. Here, we evaluated the predictive skills of the Joint UK Land Environmental Simulator (JULES) to capture spatio‐temporal variations in carbon isotope discrimination (Δ13C) reconstructed by tree rings at 12 sites in the United Kingdom over the period 1979–2016. Modeled and measured Δ13C time series were compared at each site and their relationships with local climate investigated. Modeled Δ13C time series were significantly correlated (p < 0.05) with tree‐ring Δ13C at eight sites, but JULES underestimated mean Δ13C values at all sites, by up to 2.6‰. Differences in mean Δ13C may result from post‐photosynthetic isotopic fractionations that were not considered in JULES. Inter‐annual variability in Δ13C was also underestimated by JULES at all sites. While modeled Δ13C typically increased over time across the UK, tree‐ring Δ13C values increased only at five sites located in the northern regions but decreased at the southern‐most sites. Considering all sites together, JULES captured the overall influence of environmental drivers on Δ13C but failed to capture the direction of change in Δ13C caused by air temperature, atmospheric CO2and vapor pressure deficit at some sites. Results indicate that the representation of carbon‐water coupling in JULES could be improved to reproduce both the trend and magnitude of interannual variability in isotopic records, the influence of local climate on Δ13C, and to reduce uncertainties in predicting vegetation‐environment interactions.
Loss of KDM5B ameliorates pathological cardiac fibrosis and dysfunction by epigenetically enhancing ATF3 expression
Authors: Wang Bo , Tan Yong , Zhang Yunkai , Zhang Sheng , Duan Xuewen , Jiang Yuyu , Li Tong , Zhou Qingqing , Liu Xingguang , Zhan Zhenzhen 
Published: December 2022

AbstractExcessive cardiac fibrosis is central to adverse cardiac remodeling and dysfunction leading to heart failure in many cardiac diseases. Histone methylation plays a crucial role in various pathophysiological events. However, the role of histone methylation modification enzymes in pathological cardiac fibrosis needs to be fully elucidated. Here, we identified lysine demethylase 5B (KDM5B), a histone H3K4me2/me3 demethylase, as a key epigenetic mediator of pathological cardiac fibrosis. KDM5B expression was upregulated in cardiac fibroblasts and myocardial tissues in response to pathological stress. KDM5B deficiency markedly ameliorated cardiac fibrosis, improved cardiac function, and prevented adverse cardiac remodeling following myocardial infarction (MI) or pressure overload. KDM5B knockout or inhibitor treatment constrained the transition of cardiac fibroblasts to profibrogenic myofibroblasts and suppressed fibrotic responses. KDM5B deficiency also facilitated the transformation of cardiac fibroblasts to endothelial-like cells and promoted angiogenesis in response to myocardial injury. Mechanistically, KDM5B bound to the promoter of activating transcription factor 3 (Atf3), an antifibrotic regulator of cardiac fibrosis, and inhibited ATF3 expression by demethylating the activated H3K4me2/3 modification, leading to the enhanced activation of TGF-β signaling and excessive expression of profibrotic genes. Our study indicates that KDM5B drives pathological cardiac fibrosis and represents a candidate target for intervention in cardiac dysfunction and heart failure.
Graphlets in comparison of Petri net-based models of biological systems
Authors: Szawulak Bartłomiej , Formanowicz Piotr 
Published: December 2022

AbstractCapability to compare biological models is a crucial step needed in an analysis of complex organisms. Petri nets as a popular modelling technique, needs a possibility to determine the degree of structural similarities (e.g., comparison of metabolic or signaling pathways). However, existing comparison methods use matching invariants approach for establishing a degree of similarity, and because of that are vulnerable to the state explosion problem which may appear during calculation of a minimal invariants set. Its occurrence will block usage of existing methods. To find an alternative for this situation, we decided to adapt and tests in a Petri net environment a method based on finding a distribution of graphlets. First, we focused on adapting the original graphlets for notation of bipartite, directed graphs. As a result, 151 new graphlets with 592 orbits were created. The next step focused on evaluating a performance of the popular Graphlet Degree Distribution Agreement (GDDA) metric in the new environment. To do that, we decided to use randomly generated networks that share typical characteristics of biological models represented in Petri nets. Our results confirmed the usefulness of graphlets and GDDA in Petri net comparison and discovered its limitations.
Impaired pulmonary and muscle function during moderate exercise in female patients recovered from SARS-CoV-2
Authors: Pleguezuelos Eulogio , Del Carmen Amin , Moreno Eva , Ortega Pilar , Robles Alejandro , Serra-Prat Mateo , Miravitlles Marc , Yebenes Joan Carles , Garnacho-Castaño Manuel V. 
Published: December 2022

AbstractThis study aimed to assess pulmonary and muscle dysfunction by analyzing the slow component of oxygen uptake (VO2SC), and mechanical and ventilatory efficiency in adult women recovered from the severe acute respiratory syndrome coronavirus type II (SARS-CoV-2) during a constant load test. 32 women (N = 17 patients with SARS-CoV-2; N = 15 control group) performed two cardiopulmonary exercise tests (CPX) on a cycle ergometer. In the first test, the participants performed incremental CPX until extenuation. In the second test the participants performed a 10-min CPX at a constant load intensity (watts) corresponding to the first ventilatory threshold. There was a 48–72 h rest period between the two tests. There was a significant increase in the VO2SC in the patients recovered from SARS-CoV-2 (160.4 ± 60 mL min−1) in comparison with the healthy participants (59.6 ± 65 mL min−1) (P < 0.001). Mechanical efficiency significantly decreased in patients recovered from SARS-CoV-2 compared to the control group (P = 0.04). Ventilatory inefficiency significantly increased in the patients recovered from SARS-CoV-2 compared with the control group (P < 0.001). Adult women recovered from SARS-CoV-2 infection have important pulmonary and muscular dysfunction and fatigue which contributes to increasing the VO2SC and reducing mechanical and ventilatory efficiency during mild-moderate exercise at a constant load.
Homogenous Iron-Catalysed Deuteration of Electron-Rich Arenes and Heteroarenes
Authors: Junge Kathrin , Beller Matthias , Bourriquen Florian 
Published: December 2022

AbstractDeuterated organic molecules are of interest for many applications ranging from mechanistic investigations in basic organic and physical chemistry to the development of new pharmaceuticals. Thus, methodologies for isotope-labelling reactions continue to be important. Here, a convenient methodology for hydrogen/deuterium exchange reactions in electron-rich arenes is reported using simple iron salts and deuterium oxide as isotope source.
Diastereoselective Synthesis of Substituted Chromenopyrrolidinones from Amino Acid Derived Nitriles
Authors: Koskinen Ari M. P. , Heikinheimo Annakaisa , Nieger Martin 
Published: December 2022

AbstractNovel substituted chromenopyrrolidinones were synthesized from natural amino acid derivatives through an unprecedented route involving a Knoevenagel/transesterification sequence and an allylative palladium-catalyzed cyclization reaction. The products were nature-inspired heterocycles derived from natural amino acids. The targets were synthesized with varying degrees of stereoselectivity: racemization is a known issue with amino acids, and this provided a formidable challenge to our method development. In total, six derivatives were synthesized in moderate to good yields.