bluuebunny/crossref_metadata_2025 huggingface dataset:
Aeroacoustic sources analysis of wake-ingesting propeller noise
Authors: Yangzhou Jianyun , Wu Jiafeng , Ma Zhaokai , Huang Xun
Published: May 2023

High resolution aeroacoustic source analysis is a prerequisite to address the noise concerns and release the full benefits of wake-ingesting propellers. In this work, the aeroacoustic sources of a two-bladed propeller ingesting the wake of an aerofoil are investigated using large eddy simulation in conjunction with two different source identifying approaches. The first approach is the numerical beamforming that utilizes both the classical and wavelet-based beamforming techniques, which determine the phase variations of sources at the low to mid frequencies and reveal that the high-frequency sources are phase-independent. To further improve the spatial resolution of source identification, a new near-field aeroacoustic source analysis approach based on the acoustic analogy is developed in this work. In particular, the on-surface source terms emanating the far-field noise are derived based on the Ffowcs Williams and Hawkings equation for low Mach number flows and constant rotating propellers. Through the incorporation of the simulation results into the proposed source analysis approach, various types of aeroacoustic sources are identified and studied by visualizing their distributions on the propeller surfaces, correlating to flow features and examining the noise spectra and directivity. While the leading edge sources are highly correlated with the wake interaction process, the sources at the mid-chord and the trailing edge of the blade can maintain their strength across most revolving angles. Overall, the proposed analysis approaches extend the capability of computational fluid dynamics and enable the detailed study of noise generation mechanisms of wake-ingesting propeller noise.
The inner and outer solutions to the inertial flow over a rolling circular cylinder
Authors: Terrington S.J. , Thompson M.C. , Hourigan K.
Published: May 2023

This paper proposes a new approach for evaluating numerically the forces and moments applied to a circular cylinder that is immersed in a fluid and which translates and rotates near a plane wall. Under the proposed approach, the flow is decomposed into inner and outer flows. The inner flow represents the flow in the thin interstice between the cylinder and the wall, and is obtained as an analytic expression using lubrication theory. The outer flow represents the flow far from the interstice, which does not depend on the magnitude of the gap between the cylinder and the wall, when the gap is small. The outer flow is obtained using numerical simulation as a function of both the Reynolds number and the slip coefficient. The force and moment coefficients are then obtained, as functions of the Reynolds number, slip coefficient and gap-to-diameter ratio, by combining the inner and outer solutions. Importantly, since the outer flow does not depend on the gap-to-diameter ratio, the parameter space to be explored by numerical simulations is greatly reduced compared to using finite gap ratio simulations. Moreover, the numerical difficulties associated with resolving the interstitial flow are avoided. The proposed approach can be extended to a wide range of rolling bodies, including spherical particles and wheels, and should significantly reduce the computational expense required to model the hydrodynamic forces and predict the subsequent motion of such bodies.
Assessing passive scalar dynamics in bubble-induced turbulence using direct numerical simulations
Authors: Hidman Niklas , Ström Henrik , Sasic Srdjan , Sardina Gaetano
Published: May 2023

By using direct numerical simulations (DNS) of bubbly flows with passive scalars, we show a transition in the scalar spectra from a

$k^{-5/3}$

to a

$k^{-3}$

scaling with the wavenumber

$k$

, in contrast with those of single-phase isotropic turbulence. For cases with a mean scalar gradient in the horizontal direction, the scalar spectrum decays faster than

$k^{-3}$

at high wavenumbers. While the

$k^{-3}$

scaling is well established in the bubbly flow velocity spectrum, the scalar spectrum behaviour is not fully understood. We find that the transition length scale of the scalar spectra is comparable to or below the bubble diameter and decreases with the molecular diffusivity of the scalar in the liquid. We use DNS to compute the scalar spectrum budget and show that the scalar fluctuations are produced by the mean scalar gradient at length scales above the bubble diameter, contrary to the velocity fluctuations. At length scales below the bubble diameter, the net scalar transfer scales as

$k^{-1}$

inducing the

$k^{-3}$

scaling of the scalar spectra. This finding is consistent with the hypothesis proposed by Dung et al. (J. Fluid Mech., vol. 958, 2023, p. A5) about the physical mechanism behind the

$k^{-3}$

scaling. We also show dependencies of the bubble suspension's convective scalar diffusivity on the gas volume fraction and molecular diffusivity that differ based on the direction of the mean scalar gradient. For a mean scalar gradient in the vertical direction, we find and qualitatively explain a significant effect of the molecular diffusivity in the gas on the convective scalar diffusivity.
The buoyancy staircase limit in surface quasigeostrophic turbulence
Authors: Yassin Houssam
Published: May 2023

Surface buoyancy gradients over a quasigeostrophic fluid permit the existence of surface-trapped Rossby waves. The interplay of these Rossby waves with surface quasigeostrophic turbulence results in latitudinally inhomogeneous mixing that, under certain conditions, culminates in a surface buoyancy staircase: a meridional buoyancy profile consisting of mixed zones punctuated by sharp buoyancy gradients, with eastward jets centred at the sharp gradients and weaker westward flows in between. In this article, we investigate the emergence of this buoyancy staircase limit in surface quasigeostrophic turbulence and we examine the dependence of the resulting dynamics on the vertical stratification. Over decreasing stratification ($\mathrm {d}N(z)/\mathrm {d}z\leq 0$, where$N(z)$is the buoyancy frequency), we obtain flows with a longer interaction range (than in uniform stratification) and highly dispersive Rossby waves. In the staircase limit, we find straight jets that are perturbed by eastward propagating along jet waves, similar to two-dimensional barotropic$\beta$-plane turbulence. In contrast, over increasing stratification ($\mathrm {d}N(z)/\mathrm {d}z\geq 0$), we obtain flows with shorter interaction range and weakly dispersive Rossby waves. In the staircase limit, we find sinuous jets with large latitudinal meanders whose shape evolves in time due to the westward propagation of weakly dispersive along jet waves. These along jet waves have larger amplitudes over increasing stratification than over decreasing stratification, and, as a result, the ratio of domain-averaged zonal to meridional speeds is two to three times smaller over increasing stratification than over decreasing stratification. Finally, we find that, for a given Rhines wavenumber, jets over increasing stratification are closer together than jets over decreasing stratification.
From American to Cisse: Sufism and the remaking of diasporic ties across the Atlantic
Authors: Rahman Samiha
Published: May 2023

Since the 1980s, hundreds of predominantly working-class African-American Muslims have travelled or relocated to the rural yet renowned city of Medina Baye, Senegal. They were invited there by Shaykh Hassan Cisse, a Senegalese Islamic scholar and leader in the Tijani tariqa (Sufi order). This article focuses on the experiences of African-American and fellow diaspora Black Muslims living and learning with African Muslims in the Tijani hub of Medina Baye. It interrogates the assumptions, expectations and misunderstandings that characterize relationships between the two groups. I argue that, as members of the Tijani tariqa, diaspora Black disciples become integrated within the local system of collective care modelled by African disciples. Complicating analyses of African–diasporic exchanges that tend to differentiate and hierarchize the interconnected economic hardships facing diaspora Black and continental African communities, I argue that the relationship between these groups illustrates the role of Shaykh Ibrahim Niasse’s branch of the Tijani tariqa as a counterhegemonic social movement offering new paradigms of social and economic reciprocity that enable Black Muslims on both sides of the Atlantic to mitigate the contemporary impacts of racial capitalism and global apartheid.
Initiative to increase family presence and participation in daily rounds on a paediatric acute care cardiology unit
Authors: Gal Dana B. , Pater Colleen M. , McGinty Mackenzie , Lobes Greta , Tuemler Christy , Eldridge Paula M. , Frakes Brittany , Marcuccio Elisa , Hanke Samuel P. , Gaies Michael G.
Published: May 2023

Introduction:

Family-centred rounds benefit families and clinicians and improve outcomes in general paediatrics, but are understudied in subspecialty settings. We sought to improve family presence and participation in rounds in a paediatric acute care cardiology unit.

Methods:

We created operational definitions for family presence, our process measure, and participation, our outcome measure, and gathered baseline data over 4 months of 2021. Our SMART aim was to increase mean family presence from 43 to 75% and mean family participation from 81 to 90% by 30 May, 2022. We tested interventions with iterative plan-do-study-act cycles between 6 January, 2022 and 20 May, 2022, including provider education, calling families not at bedside, and adjustment to rounding presentations. We visualised change over time relative to interventions with statistical control charts. We conducted a high census days subanalysis. Length of stay and time of transfer from the ICU served as balancing measures.

Results:

Mean presence increased from 43 to 83%, demonstrating special cause variation twice. Mean participation increased from 81 to 96%, demonstrating special cause variation once. Mean presence and participation were lower during high census (61 and 93% at project end) but improved with special cause variation. Length of stay and time of transfer remained stable.

Conclusions:

Through our interventions, family presence and participation in rounds improved without apparent unintended consequences. Family presence and participation may improve family and staff experience and outcomes; future research is warranted to evaluate this. Development of high level of reliability interventions may further improve family presence and participation, particularly on high census days.
Seismological Stress Drops for Confined Ruptures Are Invariant to Normal Stress
Authors: Steinhardt Will , Dillavou Sam , Agajanian Mary , Rubinstein Shmuel M. , Brodsky Emily E.
Published: May 2023

Seismic moment and rupture length can be combined to infer stress drop, a key parameter for assessing earthquakes. In natural earthquakes, stress drops are largely depth‐independent, which is surprising given the expected dependence of frictional stress on normal stresses and hence overburden. We have developed a transparent experimental fault that allows direct observation of thousands of slip events, with ruptures that are fully contained within the fault. Surprisingly, the observed stress drops are largely independent of both the magnitude of normal stress and its heterogeneity, capturing the independence seen in nature. However, we observe larger, normal stress‐dependent stress drops when the fault area is reduced, which allows slip events to frequently reach the edge of the interface. We conclude that confined ruptures have normal stress independent stress drops, and thus the depth‐independent stress drops of tectonic earthquakes may be a consequence of their confined nature.
Reconsidering the Relationship Between Gulf Stream Transport and Dynamic Sea Level at U.S. East Coast
Authors: Chi Lequan , Wolfe Christopher L. P. , Hameed Sultan
Published: May 2023

The relationship between Gulf Stream (GS) transport and coastal sea level is investigated using monthly GS transport between 1993 and 2019 at Florida Straits and 10 altimeter tracks. The results show that GS transport decorrelates quickly along its path, indicating it is misleading to assume that transport at a particular location represents strength of the GS as a whole. GS transport south of Cape Hatteras is significantly correlated with coastal sea level in South Atlantic Bight from both altimetry and tide gauges. North of Cape Hatteras, sea level changes associated with GS transport decay rapidly away from GS on the onshore side and become negligible approximately 300 km northwest of GS axis. In this region, the correlations between GS transport and sea level are primarily in the deep ocean and rarely on the shelf, indicating that coastal sea level is unlikely to be driven by geostrophic adjustment to changes in GS transport.
Observation of SLAMS‐Like Structures Close to Martian Aphelion by MAVEN
Authors: Shuvalov S. D. , Grigorenko E. E.
Published: May 2023

According to various orientation of the interplanetary magnetic field (IMF), the planetary shock can be either quasi‐parallel or quasi‐perpendicular. Under quasi‐parallel conditions a significant number of solar wind suprathermal particles are reflected from the shock and drift along IMF, forming an extended and highly turbulent region called the foreshock where various nonlinear plasma phenomena are observed. In this research, a case study of the structures in the foreshock region at Mars as observed by Mars Atmosphere and Volatile Evolution is performed close to Martian aphelion, when the foreshock wave activity is usually low. Data from plasma analyzer STATIC and magnetometer MAG is used to analyze ion beams angular spectrum and magnetic field dynamics. It is shown that the observed structures are consistent with Short Large‐Amplitude Magnetic Structures (SLAMS), commonly detected in foreshock regions of magnetized and unmagnetized bodies throughout the Solar system. Finally, the Alfven Mach number is calculated to analyze characteristics of the observed foreshock structures. The analysis shows that the observed SLAMS‐like structures at Mars are steepened waves formed by the ion cyclotron resonance between plasma waves propagating along the IMF and the back‐streaming scattered solar wind H+ and exospheric O+ and O2+ ions, with the dominant impact of O+ ions. The steepening process is accompanied with observation of gradients in the diffuse ion density near the bowshock, like it has been previously reported near the Earth (e.g., Scholer, 1993, https://doi.org/10.1029/92JA01875; Tsubouchi & Lembege, 2004, https://doi.org/10.1029/2003JA010014).
Influence of Shelf Break Processes on the Transport of Warm Waters Onto the Eastern Amundsen Sea Continental Shelf
Authors: Azaneu Marina , Webber Benjamin , Heywood Karen J. , Assmann Karen M. , Dotto Tiago S. , Abrahamsen E. Povl
Published: May 2023

The heat transported onto the continental shelf by Circumpolar Deep Water (CDW) is the main driver of ice shelf basal melting in the Amundsen Sea. Here, we investigate the slope current system and the variability of the heat transported through the Pine Island‐Thwaites central and eastern troughs using data from five moorings deployed in the region between 5 March 2012 and 7 February 2016. Substantial variability on intermonthly time scales (3–4 months) is observed in the onshore heat flux, driven primarily by zonal wind stress north of the shelf break. Heat content, onshore flow, and heat flux are highly correlated between central and eastern troughs, which are most likely dynamically linked by the zonal wind stress forcing. This is the first time this dynamic link between troughs is observed. In the eastern the Amundsen Sea, during the El Niño of 2015/2016, strong eastward winds led to lower temperatures over the continental shelf while the onshore heat flux is intensified. We hypothesize that this anti‐correlation between heat content and heat flux results from a strengthened eastward undercurrent leading to upwelling of a colder and deeper CDW variety. These results highlight the complex and heterogeneous response of this region to environmental and the importance of velocity data for understanding the dynamics in this region. It also suggests that the hypothesized link between large‐scale atmospheric forcing (e.g., El Niño‐Southern Oscillation) and ice‐shelf melt is not produced via changes in heat content, but instead via changes in onshore heat flux.
Grid Spacing Sensitivities of Simulated Mid‐Latitude and Tropical Mesoscale Convective Systems in the Convective Gray Zone
Authors: Ramos‐Valle A. N. , Prein A. F. , Ge M. , Wang D. , Giangrande S. E.
Published: May 2023

The main objective of this study is to observationally constrain processes in tropical and midlatitude mesoscale convective systems (MCSs), and to use these constraints for model evaluation. To accomplish this, we leverage MCS observations collected at the U.S. DOE Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site in Oklahoma and ARM's mobile GoAmazon2014/15 site in Manaus, Brazil (MAO). We simulate 13 and 11 of these observed MCSs at the SGP and MAO site, respectively, using the Weather Research and Forecasting model at 12‐, 4‐, 2‐, and 1‐km horizontal grid spacing. Observations from radiosondes, surface meteorology, and radar wind profilers are used to characterize MCS properties, such as MCS timing and location, cold pools, and convective drafts, and evaluate these simulations. SGP cases are found in better agreement with observations than MAO cases, and when simulated at 2 km, outperform simulations at 1 km regarding the timing of MCS overpass and the accuracy of surface variable trends. MAO simulations suggest a consistent improvement in model accuracy with increasing model resolution in depicting the downdraft structure, the timing of MCSs, and the surface variables changes, except for the latter two metrics at 2 km. Deficiencies are still evident at km‐scales, suggesting the need for higher resolution to simulate tropical MCSs. Overall, location‐dependent improvements in MCS representation are obtained with the increasing model resolution, prompting the evaluation of sub‐km scale simulations.
An Upscaled Model of Fill‐And‐Spill Hydrological Response
Authors: Taheri Mahkameh , Ranjram Mark , Craig James R.
Published: May 2023

The hydrology of wetland‐dominated landscapes is often controlled by a fill‐and‐spill mechanism, whereby surface depressions retain water and release it once a deficit is filled. The response of these systems to precipitation/snowmelt events is influenced by the local storage deficit and connectivity between storage features. To estimate runoff generated from a heterogeneous wetland complex, a closed‐form analytical upscaled probabilistic model is developed. The mathematical solution requires information on the distribution of initial deficits and wetland local contributing areas, which may be estimated via a combination of spatial analysis and field observation. The model is used to explore the influence of spatial heterogeneity of wetland properties including deficit depth, local contributing area, and cascade depth (the number of wetlands in‐series within a cascade) on runoff response. It is also used to clarify “gatekeeper” storage features role at large scales and for systems with shallow wetland cascade depths. The proposed solution is shown to be a generalization of the well‐known Probability Distributed Model and Xinanjiang runoff models, augmented to include information about local contributing areas and wetlands connectivity. The closed form probabilistic mathematical solution is verified by comparing results with Monte Carlo simulations. The proposed runoff model has been implemented in Raven, a hydrologic model, to test the method performance in lumped runoff simulation of wetland‐dominated basins influenced by fill‐and‐spill hydrology. This study can contribute to our understanding of wetland characteristics distribution on landscape hydrology, and compensate for insufficiently resolved elevation data in flat terrains where threshold criteria are hard to estimate.
A New Origin Story for Mars’s Burns Formation
Authors: Rehnberg Morgan
Published: May 2023

The Red Planet’s Grasberg and Burns formations have different compositions today, but they may have started out the same way.
Generalizing Scaling Laws for Mantle Convection With Mixed Heating
Authors: Ferrick Amy L. , Korenaga Jun
Published: May 2023

Convection in planetary mantles is in the so‐called mixed heating mode; it is driven by heating from below, due to a hotter core, as well as heating from within, due to radiogenic heating and secular cooling. Thus, in order to model the thermal evolution of terrestrial planets, we require the parameterization of heat flux for mixed heated convection in particular. However, deriving such a parameterization from basic principles is an elusive task. While scaling laws for purely internal heating and purely basal heating have been successfully determined using the idea that thermal boundary layers are marginally stable, recent theoretical analyses have questioned the applicability of this idea to convection in the mixed heating mode. Here, we present a scaling approach that is rooted in the physics of convection, including the boundary layer stability criterion. We show that, as long as interactions between thermal boundary layers are properly accounted for, this criterion succeeds in describing relationships between thermal boundary layer (TBL) properties for mixed heated convection. The surface heat flux of a convecting fluid is locally determined by the properties of the upper TBL, as opposed to globally determined. Our foundational scaling approach can be readily extended to nearly any complexity of convection within planetary mantles.
Self-aligned single-electrode actuation of tangential and wineglass modes using PMN-PT
Authors: Erturk Ozan , Shambaugh Kilian , Park Ha-Seong , Lee Sang-Goo , Bhave Sunil A.
Published: May 2023

Considering the evolution of rotation sensing and timing applications realized in micro-electro-mechanical systems (MEMS), flexural mode resonant shapes are outperformed by bulk acoustic wave (BAW) counterparts by achieving higher frequencies with both electrostatic and piezoelectric transduction. Within the 1–30 MHz range, which hosts BAW gyroscopes and timing references, piezoelectric and electrostatic MEMS have similar transduction efficiency. Although, when designed intelligently, electrostatic transduction allows self-alignment between electrodes and the resonator for various BAW modes, misalignment is inevitable regarding piezoelectric transduction of BAW modes that require electrode patterning. In this paper transverse piezoelectric actuation of [011] oriented single crystal lead magnesium niobate–lead titanate (PMN–PT) thin film disks are shown to excite the tangential mode and family of elliptical compound resonant modes, utilizing a self-aligned and unpatterned electrode that spans the entire disk surface. The resonant mode coupling is achieved by employing a unique property of [011] PMN–PT, where the in-plane piezoelectric coefficients have opposite signs. Fabricating 1-port disk transducers, RF reflection measurements are performed that demonstrate the compound mode family shapes in the 1–30 MHz range. Independent verification of mode transduction is achieved using in-plane displacement measurements with Polytec’s laser Doppler vibrometer (LDV). While the tangential mode achieves a 40o/s dithering rate at 335 kHz resonant frequency, then = 2 wine-glass mode achieves 11.46 nm tip displacement at 8.42 MHz resonant frequency on a radius of 60 μm disk resonator in air. A single electrode resonator that can excite both tangential and wine-glass modes with such metrics lays the foundation for a BAW MEMS gyroscope with a built-in primary calibration stage.
Amygdala subdivisions exhibit aberrant whole-brain functional connectivity in relation to stress intolerance and psychotic symptoms in 22q11.2DS
Authors: Delavari Farnaz , Rafi Halima , Sandini Corrado , Murray Ryan J. , Latrèche Caren , Van De Ville Dimitri , Eliez Stephan
Published: May 2023

The amygdala is a key region in emotional regulation, which is often impaired in psychosis. However, it is unclear if amygdala dysfunction directly contributes to psychosis, or whether it contributes to psychosis through symptoms of emotional dysregulation. We studied the functional connectivity of amygdala subdivisions in patients with 22q11.2DS, a known genetic model for psychosis susceptibility. We investigated how dysmaturation of each subdivision’s connectivity contributes to positive psychotic symptoms and impaired tolerance to stress in deletion carriers. Longitudinally-repeated MRI scans from 105 patients with 22q11.2DS (64 at high-risk for psychosis and 37 with impaired tolerance to stress) and 120 healthy controls between the ages of 5 to 30 years were included. We calculated seed-based whole-brain functional connectivity for amygdalar subdivisions and employed a longitudinal multivariate approach to evaluate the developmental trajectory of functional connectivity across groups. Patients with 22q11.2DS presented a multivariate pattern of decreased basolateral amygdala (BLA)-frontal connectivity alongside increased BLA-hippocampal connectivity. Moreover, associations between developmental drops in centro-medial amygdala (CMA)-frontal connectivity to both impaired tolerance to stress and positive psychotic symptoms in deletion carriers were detected. Superficial amygdala hyperconnectivity to the striatum was revealed as a specific pattern arising in patients who develop mild to moderate positive psychotic symptoms. Overall, CMA-frontal dysconnectivity was found as a mutual neurobiological substrate in both impaired tolerance to stress and psychosis, suggesting a role in prodromal dysregulation of emotions in psychosis. While BLA dysconnectivity was found to be an early finding in patients with 22q11.2DS, which contributes to impaired tolerance to stress.
Call combinations and compositional processing in wild chimpanzees
Authors: Leroux Maël , Schel Anne M. , Wilke Claudia , Chandia Bosco , Zuberbühler Klaus , Slocombe Katie E. , Townsend Simon W.
Published: May 2023

Through syntax, i.e., the combination of words into larger phrases, language can express a limitless number of messages. Data in great apes, our closest-living relatives, are central to the reconstruction of syntax’s phylogenetic origins, yet are currently lacking. Here, we provide evidence for syntactic-like structuring in chimpanzee communication. Chimpanzees produce “alarm-huus” when surprised and “waa-barks” when potentially recruiting conspecifics during aggression or hunting. Anecdotal data suggested chimpanzees combine these calls specifically when encountering snakes. Using snake presentations, we confirm call combinations are produced when individuals encounter snakes and find that more individuals join the caller after hearing the combination. To test the meaning-bearing nature of the call combination, we use playbacks of artificially-constructed call combinations and both independent calls. Chimpanzees react most strongly to call combinations, showing longer looking responses, compared with both independent calls. We propose the “alarm-huu + waa-bark” represents a compositional syntactic-like structure, where the meaning of the call combination is derived from the meaning of its parts. Our work suggests that compositional structures may not have evolved de novo in the human lineage, but that the cognitive building-blocks facilitating syntax may have been present in our last common ancestor with chimpanzees.
The Fgf/Erf/NCoR1/2 repressive axis controls trophoblast cell fate
Authors: Lackner Andreas , Müller Michael , Gamperl Magdalena , Stoeva Delyana , Langmann Olivia , Papuchova Henrieta , Roitinger Elisabeth , Dürnberger Gerhard , Imre Richard , Mechtler Karl , Latos Paulina A.
Published: May 2023

Placental development relies on coordinated cell fate decisions governed by signalling inputs. However, little is known about how signalling cues are transformed into repressive mechanisms triggering lineage-specific transcriptional signatures. Here, we demonstrate that upon inhibition of the Fgf/Erk pathway in mouse trophoblast stem cells (TSCs), the Ets2 repressor factor (Erf) interacts with the Nuclear Receptor Co-Repressor Complex 1 and 2 (NCoR1/2) and recruits it to key trophoblast genes. Genetic ablation of Erf or Tbl1x (a component of the NCoR1/2 complex) abrogates the Erf/NCoR1/2 interaction. This leads to mis-expression of Erf/NCoR1/2 target genes, resulting in a TSC differentiation defect. Mechanistically, Erf regulates expression of these genes by recruiting the NCoR1/2 complex and decommissioning their H3K27ac-dependent enhancers. Our findings uncover how the Fgf/Erf/NCoR1/2 repressive axis governs cell fate and placental development, providing a paradigm for Fgf-mediated transcriptional control.
Reversible transitions between noradrenergic and mesenchymal tumor identities define cell plasticity in neuroblastoma
Authors: Thirant Cécile , Peltier Agathe , Durand Simon , Kramdi Amira , Louis-Brennetot Caroline , Pierre-Eugène Cécile , Gautier Margot , Costa Ana , Grelier Amandine , Zaïdi Sakina , Gruel Nadège , Jimenez Irène , Lapouble Eve , Pierron Gaëlle , Sitbon Déborah , Brisse Hervé J. , Gauthier Arnaud , Fréneaux Paul , Grossetête Sandrine , Baudrin Laura G. , Raynal Virginie , Baulande Sylvain , Bellini Angela , Bhalshankar Jaydutt , Carcaboso Angel M. , Geoerger Birgit , Rohrer Hermann , Surdez Didier , Boeva Valentina , Schleiermacher Gudrun , Delattre Olivier , Janoueix-Lerosey Isabelle
Published: May 2023

Noradrenergic and mesenchymal identities have been characterized in neuroblastoma cell lines according to their epigenetic landscapes and core regulatory circuitries. However, their relationship and relative contribution in patient tumors remain poorly defined. We now document spontaneous and reversible plasticity between the two identities, associated with epigenetic reprogramming, in several neuroblastoma models. Interestingly, xenografts with cells from each identity eventually harbor a noradrenergic phenotype suggesting that the microenvironment provides a powerful pressure towards this phenotype. Accordingly, such a noradrenergic cell identity is systematically observed in single-cell RNA-seq of 18 tumor biopsies and 15 PDX models. Yet, a subpopulation of these noradrenergic tumor cells presents with mesenchymal features that are shared with plasticity models, indicating that the plasticity described in these models has relevance in neuroblastoma patients. This work therefore emphasizes that intrinsic plasticity properties of neuroblastoma cells are dependent upon external cues of the environment to drive cell identity.
Genomic mutation landscape of skin cancers from DNA repair-deficient xeroderma pigmentosum patients
Authors: Yurchenko Andrey A. , Rajabi Fatemeh , Braz-Petta Tirzah , Fassihi Hiva , Lehmann Alan , Nishigori Chikako , Wang Jinxin , Padioleau Ismael , Gunbin Konstantin , Panunzi Leonardo , Morice-Picard Fanny , Laplante Pierre , Robert Caroline , Kannouche Patricia L. , Menck Carlos F. M. , Sarasin Alain , Nikolaev Sergey I.
Published: May 2023

Xeroderma pigmentosum (XP) is a genetic disorder caused by mutations in genes of the Nucleotide Excision Repair (NER) pathway (groups A-G) or in Translesion Synthesis DNA polymerase η (V). XP is associated with an increased skin cancer risk, reaching, for some groups, several thousand-fold compared to the general population. Here, we analyze 38 skin cancer genomes from five XP groups. We find that the activity of NER determines heterogeneity of the mutation rates across skin cancer genomes and that transcription-coupled NER extends beyond the gene boundaries reducing the intergenic mutation rate. Mutational profile in XP-V tumors and experiments with POLH knockout cell line reveal the role of polymerase η in the error-free bypass of (i) rare TpG and TpA DNA lesions, (ii) 3’ nucleotides in pyrimidine dimers, and (iii) TpT photodimers. Our study unravels the genetic basis of skin cancer risk in XP and provides insights into the mechanisms reducing UV-induced mutagenesis in the general population.
Conceptual and quantitative categorization of wave-induced flooding impacts for pedestrians and assets in urban beaches
Authors: Garzon J. L. , Ferreira Ó. , Reis M. T. , Ferreira A. , Fortes C. J. E. M. , Zózimo A. C.
Published: May 2023

Beaches combined with sloping structures are frequently the first element of defense to protect urban areas from the impact of extreme coastal flooding events. However, these structures are rarely designed for null wave overtopping discharges, accepting that waves can pass above the crest and threat exposed elements in hinterland areas, such as pedestrians, urban elements and buildings, and vehicles. To reduce risks, Early Warning Systems (EWSs) can be used to anticipate and minimize the impacts of flooding episodes on those elements. A key aspect of these systems is the definition of non-admissible discharge levels that trigger significant impacts. However, large discrepancies in defining these discharge levels and the associated impacts are found among the existing methods to assess floodings. Due to the lack of standardization, a new conceptual and quantitative four-level (from no-impact to high-impact) categorization of flood warnings (EW-Coast) is proposed. EW-Coast integrates and unifies previous methods and builds on them by incorporating field-based information. Thus, the new categorization successfully predicted the impact level on 70%, 82%, and 85% of the overtopping episodes affecting pedestrians, urban elements and buildings, and vehicles, respectively. This demonstrates its suitability to support EWSs in areas vulnerable to wave-induced flooding.
Giraffes make decisions based on statistical information
Authors: Caicoya Alvaro L. , Colell Montserrat , Amici Federica
Published: May 2023

The ability to make inferences based on statistical information has so far been tested only in animals having large brains in relation to their body size, like primates and parrots. Here we tested if giraffes (Giraffa camelopardalis), despite having a smaller relative brain size, can rely on relative frequencies to predict sampling outcomes. We presented them with two transparent containers filled with different quantities of highly-liked food and less-preferred food. The experimenter covertly drew one piece of food from each container, and let the giraffe choose between the two options. In the first task, we varied the quantity and relative frequency of highly-liked and less-preferred food pieces. In the second task, we inserted a physical barrier in both containers, so giraffes only had to take into account the upper part of the container when predicting the outcome. In both tasks giraffes successfully selected the container more likely to provide the highly-liked food, integrating physical information to correctly predict sampling information. By ruling out alternative explanations based on simpler quantity heuristics and learning processes, we showed that giraffes can make decisions based on statistical inferences.
Watercraft decontamination practices to reduce the viability of aquatic invasive species implicated in overland transport
Authors: Mohit Shrisha , Johnson Timothy B. , Arnott Shelley E.
Published: May 2023

Recreational boating activities enable aquatic invasive species (AIS) dispersal among disconnected lakes, as invertebrates and plants caught on or contained within watercraft and equipment used in invaded waterbodies can survive overland transport. Besides simple preventive measures such as "clean, drain, dry", resource management agencies recommend decontaminating watercraft and equipment using high water pressure, rinsing with hot water, or air-drying to inhibit this mode of secondary spread. There is a lack of studies assessing the efficacy of these methods under realistic conditions and their feasibility for recreational boaters. Hence, we addressed this knowledge gap via experiments on six invertebrate and plant AIS present in Ontario. Washing at high pressures of 900–1200 psi removed the most biological material (90%) from surfaces. Brief (< 10 s) exposure to water at ≥ 60 °C caused nearly 100% mortality among all species tested, except banded mystery snails. Acclimation to temperatures from 15 to 30 °C before hot water exposure had little effect on the minimum temperature required for no survival. Air-drying durations producing complete mortality were ≥ 60 h for zebra mussels and spiny waterfleas, and ≥ 6 days among plants, whereas survival remained high among snails after a week of air-drying. Hot water exposure followed by air-drying was more effective than either method separately against all species tested.
The SciQA Scientific Question Answering Benchmark for Scholarly Knowledge
Authors: Auer Sören , Barone Dante A. C. , Bartz Cassiano , Cortes Eduardo G. , Jaradeh Mohamad Yaser , Karras Oliver , Koubarakis Manolis , Mouromtsev Dmitry , Pliukhin Dmitrii , Radyush Daniil , Shilin Ivan , Stocker Markus , Tsalapati Eleni
Published: May 2023

Knowledge graphs have gained increasing popularity in the last decade in science and technology. However, knowledge graphs are currently relatively simple to moderate semantic structures that are mainly a collection of factual statements. Question answering (QA) benchmarks and systems were so far mainly geared towards encyclopedic knowledge graphs such as DBpedia and Wikidata. We present SciQA a scientific QA benchmark for scholarly knowledge. The benchmark leverages the Open Research Knowledge Graph (ORKG) which includes almost 170,000 resources describing research contributions of almost 15,000 scholarly articles from 709 research fields. Following a bottom-up methodology, we first manually developed a set of 100 complex questions that can be answered using this knowledge graph. Furthermore, we devised eight question templates with which we automatically generated further 2465 questions, that can also be answered with the ORKG. The questions cover a range of research fields and question types and are translated into corresponding SPARQL queries over the ORKG. Based on two preliminary evaluations, we show that the resulting SciQA benchmark represents a challenging task for next-generation QA systems. This task is part of the open competitions at the 22nd International Semantic Web Conference 2023 as the Scholarly Question Answering over Linked Data (QALD) Challenge.
Green synthesis, characterization, and biological evaluation of gold and silver nanoparticles using Mentha spicata essential oil
Authors: Moosavy Mir-Hassan , de la Guardia Miguel , Mokhtarzadeh Ahad , Khatibi Seyed Amin , Hosseinzadeh Neda , Hajipour Nasser
Published: May 2023

Green synthesis of bioactive nanoparticles (NPs) is getting more attractive in various fields of science including the food industry. This study investigates the green synthesizing and characterization of gold NPs (AuNPs) and silver NPs (AgNPs) produced using Mentha spicata L. (M. spicata) essential oil as well as their antibacterial, antioxidant, and in vitro cytotoxic effects. The essential oil was mixed with both Chloroauric acid (HAuCl4) and aqueous silver nitrate (AgNO3) solutions separately and incubated at room temperature for 24 h. The chemical composition of the essential oil was identified by gas chromatography coupled with a mass spectrometer detector (GC–MS). Au and Ag nanoparticles were characterized using UV–Vis spectroscopy, transmission electron microscopy, scanning electron microscopy, dynamic light scattering (DLS), X-ray diffraction (XRD) and Fourier transform infrared (FTIR). The cytotoxicity of both types of nanoparticles was evaluated using MTT assay on cancerous HEPG-2cell line by exposing them to various concentrations of both NPs for 24 h. The antimicrobial effect was evaluated by the well-diffusion technique. The antioxidant effect was determined by DPPH and ABTS tests. According to the results of GC–MS analysis, 18 components were identified, including carvone (78.76%) and limonene (11.50%). UV–visible spectroscopy showed a strong absorption peak of 563 nm and 485 nm, indicating the formation of Au NPs and Ag NPs, respectively. TEM and DLS demonstrated that AuNPs and AgNPs were predominantly spherical shaped with average sizes of 19.61 nm and 24 nm, respectively. FTIR analysis showed that biologically active compounds such as monoterpenes could assist in the formation and stabilization of both types of NPs. Additionally, XRD provided more accurate results, revealing a nano-metal structure. Silver nanoparticles exhibited better antimicrobial activity against the bacteria than AuNPs. Zones of inhibition ranging 9.0–16.0 mm were recorded for the AgNPs, while zones of 8.0–10.33 mm were observed AuNPs. In the ABTS assay, the AuNPs and AgNPs showed a dose-dependent activity and synthesized nanoparticles exhibited higher antioxidant activity than MSEO in both assays. Mentha spicata essential oil can be successfully used for the green production of Au NPs and Ag NPs. Both green synthesized NPs show antibacterial, antioxidant, and in vitro cytotoxic activity.
Sentiments analysis of fMRI using automatically generated stimuli labels under naturalistic paradigm
Authors: Mahrukh Rimsha , Shakil Sadia , Malik Aamir Saeed
Published: May 2023

Our emotions and sentiments are influenced by naturalistic stimuli such as the movies we watch and the songs we listen to, accompanied by changes in our brain activation. Comprehension of these brain-activation dynamics can assist in identification of any associated neurological condition such as stress and depression, leading towards making informed decision about suitable stimuli. A large number of open-access functional magnetic resonance imaging (fMRI) datasets collected under naturalistic conditions can be used for classification/prediction studies. However, these datasets do not provide emotion/sentiment labels, which limits their use in supervised learning studies. Manual labeling by subjects can generate these labels, however, this method is subjective and biased. In this study, we are proposing another approach of generating automatic labels from the naturalistic stimulus itself. We are using sentiment analyzers (VADER, TextBlob, and Flair) from natural language processing to generate labels using movie subtitles. Subtitles generated labels are used as the class labels for positive, negative, and neutral sentiments for classification of brain fMRI images. Support vector machine, random forest, decision tree, and deep neural network classifiers are used. We are getting reasonably good classification accuracy (42–84%) for imbalanced data, which is increased (55–99%) for balanced data.
Influence of load partial factors adjustment on reliability design of RC frame structures in China
Authors: Cheng Kaikai , Weng Guangyuan , Cheng Zhengjie
Published: May 2023

The partial factor method has been widely used in building design and the partial factors to ensure the safety of structures are specified in the adopted codes. The load partial factors in the design expressions have been increased in the lasted code in China, which leads to theoretically increment in reliability and a growth in the consumption of construction materials. However, the influence of load partial factors adjustment on design of building structures arises different points among scholars. Some believe that it has a great impact on the design, some think the influence is small. This makes designers have doubts in the safety of structures and investors are also confused about the cost. In order to illustrate the influence of load partial factor adjustment on safety level and material consumption of RC (Reinforced Concrete) frame structures, reliability analysis and material consumption analysis are performed using First Order Reliability Method (FORM). The approach is carried out according to the load partial factors in Chinese codes of (GB50153-2008) and (GB50068-2018), respectively. Then, the influence of load partial factors adjustment is demonstrated with a case design of RC frame structures with different load partial factors in codes. The results show that the partial factor has a noticeable influence on the reliability index. The adjustment of load partial factors in design leads to an increase of the reliability index, which is about 8–16%. The increase of material consumption used in RC structures is about 0.75–6.29%. And the case indicated that the adjustment of load partial factors mainly result in the increase of reinforcement consumption, while have little effect on the concrete consumption. This study provides an analytical and conclusive insight into the influence of load partial factor adjustment on safety level and material consumption, which is can be applied to a wide range of structures.
Study on web pillar failure mechanism during auger mining and its associated risk assessment
Authors: Jiang Juyu , Sun Jianxiong , Wang Dong , Lu Ye , Cai Mingxiang , Li Lei
Published: May 2023

To safely and efficiently recover trapped coal under final endwalls in open cut mines, theoretical analysis and numerical calculation were used to study the stability of web pillar during auger mining. The partial ordered set (poset) evaluation model was used to develop a risk assessment methodology, and auger mining at Pingshuo Antaibao open cut coal mine was used as a field example for validation. Based on the catastrophe theory, the failure criterion of web pillar was established. From the limit equilibrium theory, the maximum allowable plastic yield zone width and minimum web pillar width were proposed under various Factor of Safety (FoS) thresholds. This in turn provides a new method for web pillar design. Based on the poset theory and combining with the risk evaluation and proposed hazard levels, input data were standardized and weighted. Subsequently, the comparison matrix, HASSE matrix and HASSE diagram were established. The study shows that: when the width of the plastic zone of web pillar exceeds 88% of the total width, web pillar may be unstable. Based on the calculation formula for the required width of web pillar, the required pillar width was 4.93 m and it was deemed as “mostly stable”. This was consistent with the field condition on site. Such that this method was validated.