bluuebunny/crossref_metadata_2025_split huggingface dataset:
DERIVED NON-ARCHIMEDEAN ANALYTIC HILBERT SPACE
Authors: António Jorge , Porta Mauro 
Published: August 2020

AbstractIn this short paper, we combine the representability theorem introduced in [Porta and Yu, Representability theorem in derived analytic geometry, preprint, 2017, arXiv:1704.01683; Porta and Yu, Derived Hom spaces in rigid analytic geometry, preprint, 2018, arXiv:1801.07730] with the theory of derived formal models introduced in [António, $p$-adic derived formal geometry and derived Raynaud localization theorem, preprint, 2018, arXiv:1805.03302] to prove the existence representability of the derived Hilbert space $\mathbf{R}\text{Hilb}(X)$ for a separated $k$-analytic space $X$. Such representability results rely on a localization theorem stating that if $\mathfrak{X}$ is a quasi-compact and quasi-separated formal scheme, then the $\infty$-category $\text{Coh}^{-}(\mathfrak{X}^{\text{rig}})$ of almost perfect complexes over the generic fiber can be realized as a Verdier quotient of the $\infty$-category $\text{Coh}^{-}(\mathfrak{X})$. Along the way, we prove several results concerning the $\infty$-categories of formal models for almost perfect modules on derived $k$-analytic spaces.
AI in actuarial science – a review of recent advances – part 1
Authors: Richman Ronald 
Published: August 2020

AbstractRapid advances in artificial intelligence (AI) and machine learning are creating products and services with the potential not only to change the environment in which actuaries operate but also to provide new opportunities within actuarial science. These advances are based on a modern approach to designing, fitting and applying neural networks, generally referred to as “Deep Learning.” This paper investigates how actuarial science may adapt and evolve in the coming years to incorporate these new techniques and methodologies. Part 1 of this paper provides background on machine learning and deep learning, as well as an heuristic for where actuaries might benefit from applying these techniques. Part 2 of the paper then surveys emerging applications of AI in actuarial science, with examples from mortality modelling, claims reserving, non-life pricing and telematics. For some of the examples, code has been provided on GitHub so that the interested reader can experiment with these techniques for themselves. Part 2 concludes with an outlook on the potential for actuaries to integrate deep learning into their activities. Finally, a supplementary appendix discusses further resources providing more in-depth background on machine learning and deep learning.
Germination ecology of dwarf amaranth (Amaranthus macrocarpus): an emerging weed in Australian cotton cropping systems
Authors: Asaduzzaman Md , Koetz Eric , Wu Hanwen 
Published: August 2020

AbstractDwarf amaranth (Amaranthus macrocarpus Benth.) is a problematic broadleaf weed in many crops in Australia; however, no information is available on the germination ecology of this species. Seeds from two populations of this species were collected from Hillston, NSW, Australia (D-P-01), and Yandilla, QLD, Australia (D-P-02). Seeds were germinated at a range of constant (20 to 45 C) and alternating temperatures (30/20, 35/25, 40/30, and 45/35 C day/night). For the constant temperature treatments, the highest germination occurred at 35 C for D-P-01 (89%) and D-P-02 (82%). Germination was higher at the alternating day/night temperature of 40/30 C for both populations D-P-01 (91%) and D-P-02 (85%). Seed germination of both populations was stimulated by light, which indicates a great amount of emergence of A. macrocarpus can occur on bare ground such as crop seed beds. Results also revealed that this species tolerates a moderate level of salinity and can germinate in slightly alkaline soil conditions. The emergence of this species was highest (47%) for the seed buried at 0.5-cm depth in grey cracking alkaline soil compared with seed buried at the same depth in acidic red soils. These results suggest that soil inversion by tillage to bury weed seeds below their maximum emergence depth could serve as an important tool for managing A. macrocarpus. The results from this study will help in developing more sustainable and effective integrated weed management tactics for the control of this weed and weeds with similar responses in summer cropping systems.
Holocene EASM‐EAWM Relationship Across Different Timescales in CCSM3
Authors: Yan M. , Liu Z. Y. , Ning L. , Liu J. 
Published: August 2020

AbstractThe East Asian summer monsoon and winter monsoon (EASM and EAWM) are two important components of the East Asian monsoon system. However, the relationship between the two components during the Holocene remains debated in the observation. Here, we use a set of simulations in CCSM3 to investigate the EASM‐EAWM relation across different timescales during the Holocene. It is shown that the intensities of EASM and EAWM are positively correlated at orbital timescale but negatively correlated from millennial down to multidecadal timescales. The positive correlation at orbital timescales is forced by the seasonal insolation forcing, while the negative correlation at millennial and shorter timescales is caused mainly by the internal variability of the Atlantic Meridional Overturning Circulation (AMOC) and the subsequent teleconnection to East Asia via land‐sea thermal contrast.
Link Between CO2‐Induced Wettability and Pore Architecture Alteration
Authors: Wang Heng , Alvarado Vladimir , Smith Erik R. , Kaszuba John P. , Bagdonas Davin A. , McLaughlin J. Fred , Quillinan Scott Austin 
Published: August 2020

AbstractChanges in pore (throat) size, surface roughness, and mineralogy induced by supercritical CO2‐water‐rock reactions impact petrophysical properties such as porosity, permeability, and especially wettability. Herein, we show that these changes directly impact relative permeability and capillary pressure curves, a fact rarely studied in the literature. In this work, we show that CO2 contact angle changes emerge after Madison Limestone samples were soaked for 400 hr in CO2‐enriched brine. Coreflooding results show that the water production rate and cumulative water production increased after the rock was exposed to carbonic acid. Moreover, the mercury capillary pressure decreased in mesopores and macropores, indicating the increase of size in these pores due to reactions. This compounded wettability and pore network alteration can directly affect CO2 injectivity, migration, and storage capacity. This fundamental insight into CO2 geological storage processes should aid practitioners to reduce uncertainties in forecasting CO2 distribution via injection simulation.
Limited Regional Aerosol and Cloud Microphysical Changes Despite Unprecedented Decline in Nitrogen Oxide Pollution During the February 2020 COVID‐19 Shutdown in China
Authors: Diamond Michael S. , Wood Robert 
Published: August 2020

AbstractFollowing the emergence of a novel coronavirus in Wuhan, China instituted shutdown measures starting in late January and continuing into February 2020 to arrest the spread of disease. This resulted in a sharp economic contraction unparalleled in recent Chinese history. Satellite retrievals show that nitrogen dioxide pollution declined by an unprecedented amount (~50% regionally) from its expected unperturbed value, but regional‐scale column aerosol loadings and cloud microphysical properties were not detectably affected. The disparate impact is tied to differential economic impacts of the shutdown, in which transportation, a disproportionate source of nitrogen oxide emissions, underwent drastic declines (~90% reductions in passenger traffic), whereas industry and power generation, responsible for >90% of particulate emissions, were relatively less affected (~20% reductions in electricity and thermal power generation). A combination of anomalously warm and humid meteorological conditions and complex chemical interactions further decreased nitrogen dioxide concentrations but likely enhanced secondary aerosol formation.
Tidal Grounding‐Line Migration Modulated by Subglacial Hydrology
Authors: Warburton K. L. P. , Hewitt D. R. , Neufeld J. A. 
Published: August 2020

AbstractWe present a mathematical model of the hydrology of grounding‐line migration on tidal timescales, in which the ice acts elastically, overlying a connected hydrological network, with the ocean tides modeled by an oscillating far‐field fluid height. The upstream grounding‐line migration is driven by a fluid pressure gradient through the grounding zone, while the downstream migration is limited by fluid drainage through the till. The two processes are described using separate travelling‐wave solutions, based on a model of fluid flow under an elastic sheet. The asymmetry between the upstream and downstream motion allows the grounding line to act as a nonlinear filter on the tidal forcing as the pressure signal propagates upstream, and this frequency modulation is discussed in the context of velocity data from ice streams across Antarctica to provide a novel constraint on till permeability.
The Robustness of Pressure‐Driven Asthenospheric Flow in Mantle Convection Models With Plate‐Like Behavior
Authors: Semple Alana , Lenardic Adrian 
Published: August 2020

AbstractRecent seismic observations challenge the conventional view that tectonic plates are driven by slab pull and ridge push forces. The observations indicate that the asthenosphere flows faster and in a different direction than the plate above. Previous mantle convection models argued that pressure‐driven flow, in combination with a non‐Newtonian upper mantle, can account for these observations. We expand those models by introducing a formulation that allows for the development of weak plate margins. Weak plate margins lead to an increase in the ratio of slab‐driven to pressure‐driven asthenosphere flow, but pressure‐driven flow remains active and increases with plate margin strength. Locally, the asthenosphere can drive plates and can change flow direction with depth. Furthermore, a non‐Newtonian upper mantle allows for a hysteresis effect where, depending on initial conditions, single‐plate and plate tectonic modes can exist at the same parameter conditions.
Electron Temperature Inversion by Stimulated Brillouin Scattering During Electron Gyroharmonic Heating at EISCAT
Authors: Fu H. Y. , Jiang M. L. , Wang K. N. , Wu J. , Li Q. L. , Rietveld M. T. , Varberg E. , Häggström I. , Jin Y.‐Q. 
Published: August 2020

AbstractThis work reports a holistic experimental investigation of stimulated Brillouin scattering (SBS) features and electron temperature inversion near the third electron gyroharmonic 3fce using the European Incoherent Scatter (EISCAT) heating facility. The evolution of SBS features including spectral offset, width, and power varies asymmetrically near 3fce. The asymmetries among SBS, electron temperature, and high frequency‐enhanced ion lines are clearly exhibited for pumping above f0 ≥ 3fce. Electron temperature Te at the resonance regime has been retrieved from the measured SBS spectra based on the wave matching theory. The inversion results by SBS are consistent with measurement by the EISCAT UHF incoherent scatter radar (ISR) at the resonance altitude. The comparison of electron temperature Te and ion temperature Ti between SBS and ISR enlightens great potentials for developing realistic ionospheric diagnostic technique.
Seasonal Variability of Mercury's Sodium Exosphere Deduced From MESSENGER Data and Numerical Simulation
Authors: Suzuki Y. , Yoshioka K. , Murakami G. , Yoshikawa I. 
Published: August 2020

AbstractMercury is valuable to us because we can see the interactions between the planet and its space environment. This research aims to clarify how Mercury's neutral Na exosphere was produced. Data from MErcury Surface, Space ENvironment, GEochemistry, and Ranging/Mercury Atmospheric and Surface Composition Spectrometer (MESSENGER/MASCS) and model calculations that examine possible generation, transportation, and dissipation processes were compared. First, the seasonal variability in the amount of Na exosphere was analyzed for each local time (LT) using MASCS data. Previous research has shown that the amount of Na above LT12 reaches its maximum at the aphelion and that this maximum is recorded only at LT12. Following this result, we constructed a 3‐D Na exosphere model to understand the key seasonal variability processes occurring around LT12. The numerical calculation produced results that were consistent with the MASCS observations regarding the vertical profile and the seasonal variability at LT06 and LT18. However, the peak that occurs around the aphelion at LT12 could not be reproduced. However, the model produced results suggesting that less than 108 kg of comet stream dust particles per Mercury year could be the local and short‐term source of Na.
Lost Volatiles During the Formation of Hollows on Mercury
Authors: Wang Yichen , Xiao Zhiyong , Chang Yiren , Cui Jun 
Published: August 2020

AbstractHollows are the key to understand the composition and evolution of volatiles in the planet Mercury. A fundamental question about the formation mechanism of hollows is the true reflectance spectra of the possible volatile compounds. We use the high‐resolution images and reflectance spectra returned by the MESSENGER spacecraft to investigate the nature and origin of hollows on Mercury. Hollows are divided as different geomorphological facies according to their morphology and possible degree of devolatilization, and reflectance spectra for different facies of hollows are extracted. Large sample analyses reveal that the spectra of hollow floors and background terrains are the two end‐members, whose mixtures can account for the observed wide ranges of reflectance spectra of hollows. Spectral analyses favor that carbon might be a volatile compound that formed hollows, although direct spectral observations for the hollow‐forming volatiles are prohibited because volatiles are mainly lost from steep hollow walls. The initiation and growth of hollows are controlled by structural heterogeneities in the subsurface, such as widespread cooling fractures that were developed in melt sheets of complex craters. A maximum model age of 103 (+200, −96) thousand years is derived for the global population of hollows, yielding an average growth rate >1,000 times that of previous estimations. Based on the geometry of the different morphological facies of all visible hollows on Mercury, the conservation of mass predicts a minimum volume of lost volatiles of 1,266 km3. We predict that an active rejuvenation of volatiles has occurred in the shallow crust of Mercury.
Measuring Basal Force Fluctuations of Debris Flows Using Seismic Recordings and Empirical Green's Functions
Authors: Allstadt Kate E. , Farin Maxime , Iverson Richard M. , Obryk Maciej K. , Kean Jason W. , Tsai Victor C. , Rapstine Thomas D. , Logan Matthew 
Published: August 2020

AbstractWe present a novel method for measuring the fluctuating basal normal and shear stresses of debris flows by using along‐channel seismic recordings. Our method couples a simple parameterization of a debris flow as a seismic source with direct measurements of seismic path effects using empirical Green's functions generated with a force hammer. We test this method using two large‐scale (8 and 10 m3) experimental flows at the U.S. Geological Survey debris‐flow flume that were recorded by dozens of three‐component seismic sensors. The seismically derived basal stress fluctuations compare well in amplitude and timing to independent force plate measurements within the valid frequency range (15–50 Hz). We show that although the high‐frequency seismic signals provide band‐limited forcing information, there are systematic relations between the fluctuating stresses and independently measured flow properties, especially mean basal shear stress and flow thickness. However, none of the relationships are simple, and since the flow properties also correlate with one another, we cannot isolate a single factor that relates in a simple way to the fluctuating forces. Nevertheless, our observations, most notably the gradually declining ratio of fluctuating to mean basal stresses during flow passage and the distinctive behavior of the coarse, unsaturated flow front, imply that flow style may be a primary control on the conversion of translational to vibrational kinetic energy. This conversion ultimately controls the radiation of high‐frequency seismic waves. Thus, flow style may provide the key to revealing the nature of the relationship between fluctuating forces and other flow properties.
Effects of Temperature and Light on Methane Production of Widespread Marine Phytoplankton
Authors: Klintzsch T. , Langer G. , Wieland A. , Geisinger H. , Lenhart K. , Nehrke G. , Keppler F. 
Published: August 2020

AbstractMethane (CH4) production in the ocean surface mixed layer is a widespread but still largely unexplained phenomenon. In this context marine algae have recently been described as a possible source of CH4in surface waters. In the present study we investigated the effects of temperature and light intensity (including daylength) on CH4formation from three widespread marine algal speciesEmiliania huxleyi,Phaeocystis globosa,andChrysochromulinasp. Rates ofE. huxleyiincreased by 210% when temperature increased in a range from 10°C to 21.5°C, while a further increase in temperature (up to 23.8°C) showed reduction of CH4production rates. Our results clearly showed that CH4formation ofE. huxleyiis controlled by light: When light intensity increased from 30 to 2,670 μmol m−2 s−1, CH4emission rates increased continuously by almost 1 order of magnitude and was more than 1 order of magnitude higher when the daylength (light period) was extended from 6/18 hr light‐dark cycle to continuous light. Furthermore, light intensity is also an important factor controlling CH4emissions ofChrysochromulinasp. andP. globosaand could therefore be a species‐independent regulator of phytoplankton CH4production. Based on our results, we might conclude that extensive blooms ofE. huxleyicould act as a main regional source of CH4in surface water, since blooming ofE. huxleyiis related to the seasonal increase in both light and temperature, which also stimulate CH4production. Under typical global change scenarios,E. huxleyiwill increase its CH4production in the future.
Quantifying Convective Aggregation Using the Tropical Moist Margin's Length
Authors: Beucler Tom , Leutwyler David , Windmiller Julia M. 
Published: August 2020

AbstractOn small scales, the tropical atmosphere tends to be either moist or very dry. This defines two states that, on large scales, are separated by a sharp margin, well identified by the antimode of the bimodal tropical column water vapor distribution. Despite recent progress in understanding physical processes governing the spatiotemporal variability of tropical water vapor, the behavior of this margin remains elusive, and we lack a simple framework to understand the bimodality of tropical water vapor in observations. Motivated by the success of coarsening theory in explaining bimodal distributions, we leverage its methodology to relate the moisture field's spatial organization to its time evolution. This results in a new diagnostic framework for the bimodality of tropical water vapor, from which we argue that the length of the margin separating moist from dry regions should evolve toward a minimum in equilibrium. As the spatial organization of moisture is closely related to the organization of tropical convection, we hereby introduce a new convective organization index (BLW) measuring the ratio of the margin's length to the circumference of a well‐defined equilibrium shape. Using BLW, we assess the evolution of self‐aggregation in idealized cloud‐resolving simulations of radiative‐convective equilibrium and contrast it to the time evolution of the Atlantic Intertropical Convergence Zone (ITCZ) in the ERA5 meteorological reanalysis product. We find that BLW successfully captures aspects of convective organization ignored by more traditional metrics, while offering a new perspective on the seasonal cycle of convective organization in the Atlantic ITCZ.
Advances and challenges in retinoid delivery systems in regenerative and therapeutic medicine
Authors: Ferreira Raquel , Napoli Joseph , Enver Tariq , Bernardino Liliana , Ferreira Lino 
Published: August 2020

AbstractRetinoids regulate a wide spectrum of cellular functions from the embryo throughout adulthood, including cell differentiation, metabolic regulation, and inflammation. These traits make retinoids very attractive molecules for medical purposes. In light of some of the physicochemical limitations of retinoids, the development of drug delivery systems offers several advantages for clinical translation of retinoid-based therapies, including improved solubilization, prolonged circulation, reduced toxicity, sustained release, and improved efficacy. In this Review, we discuss advances in preclinical and clinical tests regarding retinoid formulations, specifically the ones based in natural retinoids, evaluated in the context of regenerative medicine, brain, cancer, skin, and immune diseases. Advantages and limitations of retinoid formulations, as well as prospects to push the field forward, will be presented.
Steps towards standardized quantification of adult neurogenesis
Authors: Zhao Xinyu , van Praag Henriette 
Published: August 2020

AbstractNew neurons are generated in adult mammals. Adult hippocampal neurogenesis is considered to play an important role in cognition and mental health. The number and properties of newly born neurons are regulatable by a broad range of physiological and pathological conditions. To begin to understand the underlying cellular mechanisms and functional relevance of adult neurogenesis, many studies rely on quantification of adult-born neurons. However, lack of standardized methods to quantify new neurons is impeding research reproducibility across laboratories. Here, we review the importance of stereology, and propose why and how it should be applied to the study of adult neurogenesis.
ITGB3-mediated uptake of small extracellular vesicles facilitates intercellular communication in breast cancer cells
Authors: Fuentes Pedro , Sesé Marta , Guijarro Pedro J. , Emperador Marta , Sánchez-Redondo Sara , Peinado Héctor , Hümmer Stefan , Ramón y Cajal Santiago 
Published: August 2020

AbstractMetastasis, the spread of malignant cells from a primary tumour to distant sites, causes 90% of cancer-related deaths. The integrin ITGB3 has been previously described to play an essential role in breast cancer metastasis, but the precise mechanisms remain undefined. We have now uncovered essential and thus far unknown roles of ITGB3 in vesicle uptake. The functional requirement for ITGB3 derives from its interactions with heparan sulfate proteoglycans (HSPGs) and the process of integrin endocytosis, allowing the capture of extracellular vesicles and their endocytosis-mediated internalization. Key for the function of ITGB3 is the interaction and activation of focal adhesion kinase (FAK), which is required for endocytosis of these vesicles. Thus, ITGB3 has a central role in intracellular communication via extracellular vesicles, proposed to be critical for cancer metastasis.