bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of Aquifer Poroelastic Response to Impulse and Oscillatory Well Pressure Using Distributed Acoustic Sensing
Authors: Becker Matthew W. , Harris Brett , Pevzner Roman
Published: December 2022

The storage of fluids in the subsurface is critical for a broad spectrum of applications including managed aquifer recharge, storage of liquefied carbon dioxide and hydrogen, geothermal heat extraction and exploitation of hydrocarbon. It is surprising then, that there has been relatively little measurement of the vertical distribution of poroelastic storage in geologic formations as compared with permeability. We present experiments in which fluid was injected into an important regional aquifer and the depth‐dependent strain response measured using fiber optic distributed acoustic sensing. The formation expansion and contraction in response to fluid injection were several 100 nanostrain. Strain, and the implied storage distribution, was highly localized in specific strata and demonstrated complex, hydromechanical behavior. This new window into fluid‐geomechanical coupling undermines some typically use models and observations currently in practice, but provides potential for complete representation and prediction of fluid storage in the subsurface.
Flow‐To‐Fracture Transition of Linear Maxwell‐Type Versus Yield Strength Fluids by Air Injection—Implications for Magma Fracturing
Authors: Sánchez Claudia , Ichihara Mie , Kuwano Osamu
Published: December 2022

To illuminate brittle and ductile fracturing of magma, we investigated bubble expansion and fracturing in two contrasting fluids: a Maxwell‐type viscoelastic fluid and a Bingham‐type yield‐strength fluid. Measurements of the complex shear modulus, G′ + iG″ (i is the imaginary unit), under small‐strain oscillation showed that both fluids are elastic (G′ > G″) with similar rigidity. Viscous behavior (G′ < G″) appeared at lower frequency in the Maxwell fluid but at larger strain in the Bingham fluid. When we injected air into the Maxwell fluid, bubbles expanded viscously at low flux, fractured in a brittle manner at high flux, and behaved transitionally at intermediate flux. In contrast, we observed no fracturing in the Bingham fluid. This demonstrates that the G′ > G″ condition is insufficient to infer that brittle fracturing can occur. Brittle fracturing of the Maxwell fluid occurred not at a critical strain rate but under decreasing strain rate and increasing stress.
A “Floatilla” of Airborne Seismometers for Venus
Authors: Krishnamoorthy Siddharth , Bowman Daniel C.
Published: December 2022

Barometers floating on high‐altitude balloons in the relatively clement cloud layer on Venus could detect and characterize acoustic waves generated by seismic activity, avoiding the need for high‐temperature electronics required for surface seismology. Garcia et al. (2022, https://doi.org/10.1029/2022GL098844) recently demonstrated the detection of low‐frequency sound (infrasound) caused by earthquakes of magnitudes 7.3 and 7.5 from stratospheric balloons nearly 3,000 km away from the epicenter. They provided a preliminary demonstration of earthquake magnitude and location inversion, and the determination of S‐ and Rayleigh wave velocities using only their acoustic signature. Large earthquakes produce low‐frequency seismic waves that penetrate the interiors of planets; their detection at continental‐scale distances from a high‐vantage point demonstrates the feasibility of balloon‐based investigations of Venus' interior. We contextualize these results within the effort to perform seismology on Venus from balloons, discuss its limitations, and share perspectives on open research questions in this area.
Sensitivity of the Tropical Dust Cycle to Glacial Abrupt Climate Changes
Authors: Hopcroft Peter O. , Pichat Sylvain , Valdes Paul J. , Kienast Stephanie S.
Published: December 2022

During abrupt climate changes of the last glacial period paleorecords show large amplitude changes in the dust cycle. We use Earth System model simulations to evaluate processes operating across these events. Idealized Heinrich stadial‐like simulations show a southwards migration of tropical rainfall that dries the Sahel and reduces wet deposition causing a widespread enhancement of tropical dust loading. However, several discrepancies with marine core dust deposition reconstructions are evident. Simulations with a more limited freshwater forcing (0.4 Sv instead of 1.0 Sv) and weaker cooling over the North Atlantic (less than 3°C) show a switch in sign of the stadial dust deposition anomaly in several regions, improving agreement with paleorecords. The simulated dust cycle therefore displays in places a non‐linear response to abrupt change. The global‐mean stadial dust radiative forcing in the more realistic simulations is around −0.2 to −0.6 W m−2 and so could represent an amplifying feedback during these events.
Fracture‐Mesh Faulting in the Swarm‐Like 2020 Maacama Sequence Revealed by High‐Precision Earthquake Detection, Location, and Focal Mechanisms
Authors: Shelly David R. , Skoumal Robert J. , Hardebeck Jeanne L.
Published: December 2022

In August of 2020, an earthquake sequence initiated within the Maacama fault zone in northern California, raising questions about its relationship with the larger‐scale fault. To investigate the faulting geometry and its implications for physical processes driving seismicity, we applied an integrated, multi‐faceted seismic analysis including waveform‐correlation‐based event detection, relative relocation, and high‐precision focal mechanisms. To determine mechanisms for a large population of very small earthquakes (predominantly M < 1), we combined correlation‐derived polarity analysis with a recently developed technique to determine S/P amplitude ratios from single seismic components. Finally, we applied an iterative stress inversion to distinguish between the likely fault and auxiliary planes. This analysis reveals that although the sequence initiated on a right‐lateral fault, plausibly a strand of the Maacama Fault, it also activated numerous en echelon left‐lateral conjugate faults. Together, these interlocking faults form a fracture mesh, consistent with structures associated elsewhere with fluid‐induced faulting and earthquake swarms.
Soil Stratum Tides
Authors: Shi Bin , Zhang Cheng‐Cheng , Fang Ke , Shi Songge , Wei Guangqing , Hoitink A. J. F.
Published: December 2022

River deltas, where ocean tides can often freely propagate into the river, are focal points of human settlement. Beneath the delta surface, groundwater stored in the soil strata fluctuates with river tides, resulting in pressure variations within the soil strata. Here, we introduce a novel ultra‐weak fiber‐optic instrument to test the hypothesis that tide‐induced groundwater level variations induce periodic soil stratum deformation. Using borehole deployments ranging over 70 m in the subsurface of the Yangtze Delta, we observe semidiurnal and spring–neap cycles of soil stratum deformation and reveal its dependence on lithology and depth. This allows us to coin the new term “soil stratum tide,” defined as the periodic deformation of soil strata in response to pressure fluctuations induced by tides in open water. High‐accuracy monitoring of the breathing of tidal deltas enables calibrating Earth observation systems, analysis of delta subsidence, and safeguarding of infrastructure jeopardized by soil stratum deformation.
Simultaneous Mesoscale Polar Cusp Field‐Aligned Currents Measured on Mid‐ and Low‐Altitude Satellites
Authors: Dong X.‐C. , Dunlop M. W. , Xiao C. , Wei D. , Wang T.‐Y. , Zhao J.‐S.
Published: December 2022

Using a conjunction of Cluster in the mid‐altitude dayside magnetosphere and Swarm in the low‐altitude ionosphere, we show, by employing multi‐spacecraft analysis, that matched, strong magnetic perturbations and the corresponding mesoscale field‐aligned current (FAC) structures are measured in the high latitude polar cusp region during the 7 October 2015 storm. Two pairs of opposite (positive/negative) FACs are observed by both Cluster and Swarm, which may relate to pulsed magnetic reconnection at the dayside magnetopause. Furthermore, the current intensity of these matched FACs decreases from high to low latitude, consistent with the time elapsed since reconnection. Corresponding geomagnetic disturbances are also observed by ground stations. Our observations provide direct evidence for the coupling of mesoscale FACs between the magnetosphere, ionosphere and ground in the polar cusp region, where the signatures are driven in this case by conditions suitable for inducing reconnection.
Magnetic Fields and Plasma Motions in a Hybrid Martian Magnetosphere
Authors: Dubinin E. , Fraenz M. , Pätzold M. , Tellmann S. , Modolo R. , DiBraccio G. , McFadden J. , Espley J.
Published: December 2022

The Martian magnetosphere contains elements of induced and intrinsic origin. To display them one must use different coordinate systems. Although the solar‐electric coordinate system (Mars Solar Electric [MSE]) adequately describes the main features of the induced magnetosphere, it removes/suppresses aspects caused by the crustal magnetic sources while rotating the spacecraft position to the MSE‐coordinate system and averaging over many orbits. On the other hand, to observe effects of the crustal field one should use the solar orbital coordinates (Mars Solar Orbital [MSO]). To find a compromise and keeping in mind that the most probable value of the clock angle of the interplanetary magnetic field (IMF) on the Mars orbit is ∼90° we can consider separately cases with positive and negative By components of the IMF. It is shown that dynamics of ion fluxes in the distant regions of the magnetosphere is mainly controlled by induced features. However, reconnection of the draping IMF with crustal field leads to a twisting of the classical draping configuration. Despite of the very intricate local geometry of the crustal field, the low‐order harmonics of the magnetic field and mainly the dipole component determine the reconnection sites, at least, statistically for many Mars rotations. For different signs of the By component of the IMF these sites occur either in the +Y‐MSO or −Y‐MSO hemispheres. As a result, statistically the magnetosphere of Mars looks like a hybrid magnetosphere formed during the solar wind interaction with the obstacle which simultaneously contains an extended ionosphere and a weak dipole magnetic field.
SANS: Publicly Available Daily Multi‐Scale Seismic Ambient Noise Source Maps
Authors: Igel Jonas K. H. , Bowden Daniel C. , Fichtner Andreas
Published: December 2022

Seismic ambient noise sources have received increased attention recently, creating new possibilities to study the Earth's subsurface and the atmosphere‐ocean‐solid Earth coupling. In efforts to locate such noise sources using nonlinear finite‐frequency inversions, methodological developments such as pre‐computed wavefields and spatially variable grids were necessary. These make inversions feasible for the secondary microseismic sources in a frequency range up to 0.2 Hz on a daily basis. By obtaining a starting model for the inversion using Matched Field Processing (MFP) we are able to further steer the inversion toward acceptable global noise source models and improve the final result. Analysis of 1 year of daily inversions shows the seasonal variations of the secondary microseisms and their dependence on the atmosphere‐ocean‐solid Earth coupling due to storm‐induced ocean waves. We present a web framework, seismic ambient noise sources (SANS, sans.ethz.ch), where daily regional‐ to global‐scale SANS maps for the secondary microseisms are made available to the public. This enables the implementation of time‐variable noise source distributions into full‐waveform ambient noise tomography and time‐dependent subsurface monitoring methods. Additionally, it can act as a reference for other studies that locate secondary microseismic sources on a larger scale.
Revisiting Atmospheric Features of Mars Orbiter Laser Altimeter Data Using Machine Learning Algorithms
Authors: Caillé Vincent , Määttänen Anni , Spiga Aymeric , Falletti Lola
Published: December 2022

The Mars Orbiter Laser Altimeter (MOLA) instrument has been drawing a map of Mars' topography between September 1997 and June 2001. It has also been able to observe clouds during the mission duration, providing data for the low Martian atmosphere for nearly 1.5 Mars years. The Mars Global Surveyor, which carried MOLA, also carried two other instruments that also observed clouds during the same time period (the Mars Orbiter Camera and the Thermal Emission Spectrometer). Combining observations from these three data sets could provide a complete recap of most atmospheric structures during MY24 and MY25. However, previous studies of MOLA data set often had to use stringent detection criteria. Using machine learning clustering methods, we end up finding way more atmospheric returns. Our results are presented in the form of an atmospheric features catalog that we then use to compare MOLA observations with Mars Orbiter Camera and Thermal Emission Spectrometer results, but also with more recent missions. We study the development of recurrent phenomenon in the Martian atmosphere, like the aphelion cloud belt or the south polar hood, but also spontaneous events such as regional dust storms. Methods could be tuned even more finely by using more complex clustering methods or deep learning algorithms to clearly distinguish atmospheric structures.
Cryogenic Sulfuric Weathering and Challenges for Preserving Iron‐Rich Olivine on Cold and Icy Mars
Authors: Yu Xiao‐Wen , Zhao Yu‐Yan Sara , Wu Yanxue , Qi Chao , Li Dongdong , Lin Honglei , Yang Shiling , Liu Jianzhong , Li Xiongyao
Published: December 2022

Iron‐rich olivine (Fe contents ≥20%) is widely distributed on Mars, but its dissolution rates, weathering products, and particularly Fe behavior under Mars‐relevant conditions are largely unconstrained. Here, we experimentally investigate the dissolution of synthetic Fe‐rich olivine (Fa29 to Fa100; grain size ∼53 μm) for a water‐limited cryogenic sulfuric weathering scenario at 233 K. Fayalite (Fa) and forsterite (Fo) in Fo‐dominant olivine dissolve simultaneously, whereas fayalite dissolution in Fa‐dominant olivine is hindered. Primary alteration products are FeII‐Mg‐sulfates and amorphous silica with minor ferric sulfates and gypsum. Freezing and acidic conditions enhance Fe mobility and subsequent Fe cycling on Mars. The lifetime of Fe‐rich olivine is two to three orders of magnitude shorter than that of Mg‐rich San Carlos olivine. The cryogenic sulfuric weathering scenario greatly challenges the survival of Fe‐rich olivine. Spatial and temporal restrictions for acid‐olivine interactions or insufficient sulfur supply relative to olivine are essential to preserving olivine throughout cold and icy ancient Mars.
About the Propagation of RSDN‐20 “Alpha” Signals in the Earth‐Ionosphere Waveguide During Geomagnetic Disturbances
Authors: Akhmetov O. I. , Belakhovsky V. B. , Mingalev I. V. , Mingalev O. V. , Larchenko A. V. , Suvorova Z. V.
Published: December 2022

The paper presents the results of the modeling of VLF radio waves propagation in horizontally inhomogeneous region of the high‐latitude Earth‐ionosphere waveguide during different types of the geomagnetic disturbances. The frequencies of the model source of signal correspond to the frequencies of the long‐distance navigation radio system RSDN‐20 “Alpha” constantly broadcasting in the VLF range in the Russian Federation. It is considered the geomagnetic storm on 24 January 2012 and geomagnetic substorm on 11 December 2015. Electron density profiles and collision rates of electrons with neutrals are taken from the measurements of EISCAT radar in Tromso and EISCAT 42m radar on Svalbard. The numerical experiments were conducted with a highly horizontally inhomogeneous electron density in the ionosphere. It is shown that the amplitudes and phases of the VLF signals at these frequencies show a noticeable reaction to changes in the ionospheric parameters during the considered geomagnetic disturbances. Calculations show that changes in amplitude of RSDN‐20 “Alpha” signals caused by the action of the Earth's magnetic field and horizontal inhomogeneities depend on the direction of signal propagation relative to the Earth's magnetic field vector and cannot be reversed if the direction of propagation changes to the opposite. The results of the numerical experiment were compared with the corresponding characteristics of the RSDN‐20 signals calculated from the observations of electromagnetic signals at the Lovozero observatory for the case on 11 December 2015.
Quantification and Restoration of the Pre‐Drift Extension Across the NE Atlantic Conjugate Margins During the Mid‐Permian‐Early Cenozoic Multi‐Rifting Phases
Authors: Abdelmalak Mansour M. , Gac Sébastien , Faleide Jan Inge , Shephard Grace E. , Tsikalas Filippos , Polteau Stéphane , Zastrozhnov Dmitry , Torsvik Trond H.
Published: December 2022

The formation of the NE Atlantic conjugate margins is the result of multiple rifting phases spanning from the Late Paleozoic and culminating in the early Eocene when breakup was accompanied with intense magmatic activity. The pre‐breakup configuration of the NE Atlantic continental margins is controlled by crustal extension, magmatism, and sub‐lithospheric processes, all of which need to be quantified for the pre‐breakup architecture to be restored. Key parameters that need to be extracted from the analysis of crustal structures and sediment record include stretching factors, timing of rifting phases, and nature of the deep crustal structures. The aim of this study is to quantify the pre‐drift extension of the NE Atlantic conjugate margins using interpreted crustal structure and forward basin modeling. We use a set of eight 2D conjugate crustal transects and corresponding stratigraphic models, constrained from an integrated analysis of 2D and 3D seismic and well data. The geometry and thickness of the present‐day crust is compared to a reference thickness which has experienced limited or no crustal extension since Permian time allowing the quantification of crustal stretching. Based on the eight conjugate crustal transects, the total pre‐drift extension is estimated to range between 181 and 390 km with an average of 270–295 km. These estimates are supported by the results of forward basin modeling, which predict total extension between 173 and 325 km, averaging 264 km. The cumulative pre‐drift extension estimates derived from basin modeling are in turn used to calculate the incremental crustal stretching factors at each of the three main rifting phases between the conjugate Greenland‐Norwegian margins. The mid‐Permian early Triassic rifting phase represents 32% of the total extension, while the equivalent values are 41% for the mid‐Jurassic to mid‐Cretaceous and 27% for the Late Cretaceous‐Paleocene rifting phases. These values are used to establish and present at first, a full‐fit palinspastic plate kinematic model for the NE Atlantic since the mid‐Permian and will be the base for future work on more elaborated models in order to build accurate paleogeographic and tectonic maps.
Understanding Recycled Precipitation at Different Spatio‐Temporal Scales Over India: An Eulerian Water Tagging Approach
Authors: Navale Ashish , Karthikeyan L.
Published: December 2022

Land evapotranspiration has a notable impact on the continental precipitation of India during monsoons. Given the heterogeneous land use and climate, India hosts many transition zones, which are hotspots for land‐atmosphere interactions. This work aims to study the soil moisture‐precipitation feedbacks over India by quantifying recycled precipitation using the Eulerian water vapor‐tagging technique incorporated in the Weather Research and Forecasting model. Eulerian vapor tagging techniques provide the most accurate information on recycled precipitation. We tracked the vapor originating at two spatial scales—entire India and six homogeneous monsoon regions. The latter analysis is conducted to assess inter‐regional vapor exchanges. In this process, we determined the seasonal, monthly, and diurnal variations of recycling ratio and assessed its behavior during active and monsoon break periods. We considered three contrasting monsoon seasons (surplus, normal, and deficit rainfall years) for analysis. Results show a high recycling ratio in Central India, Gangetic plain, and Northeast India. Recycling ratio increases with monsoon progression and peaks in September (∼0.30). The Himalaya and transient low‐pressure systems originating from the Bay of Bengal are vital for precipitation recycling in India. The contrasting monsoons exhibit changes in recycling ratio only at monthly scale. Regional analysis indicates West Central India is the most significant vapor contributor, while Northeast India is the highest recipient of recycled precipitation. High recycling (∼20%) shifts from central India during the active period to the foothills of Himalaya during the break period. Diurnal scale analysis reveals high afternoon recycling due to enhanced convective activity.
Sediment Dynamics and Bed Stability in Step‐Pool Streams: Insights From 18 Years of Field Observations
Authors: Hassan Marwan A. , Saletti Matteo , McDowell Conor , Li Wenqi
Published: December 2022

Step‐pools are a common morphology in gravel‐bed streams with gradients between 3% and 30%, where coarse sediment and wood are present. Recent experimental work has offered insight on the formation of step‐pools, flow resistance, and interactions between sediment transport and channel morphology. However, field observations are sparse and often limited by short observation periods. Using an extensive 18‐year data set, we examine controls on sediment mobility, step stability, and sediment storage in East Creek, a step‐pool reach in British Columbia. Event bedload yield correlated with peak flow and ranged over two orders of magnitude. For most events, bedload grain‐size was finer than the grain size distribution of the sediment found in pools. Fractional sediment mobility was independent of the flow magnitude and controlled by sediment supply. The large stones that comprise the steps were generally mobile during large events (>10‐year recurrence interval), although the largest ones were not. Despite the movement of large stones, the skeleton of the steps remained in place even during an event with a near 125‐year recurrence interval. Temporal trends in sediment storage in pools show that most events cause negligible changes in sediment storage. Our field observations indicate that the step‐pool morphology of East Creek is stable, as the morphology and shape of the steps persisted under a wide range of flows. The overall stability of the reach is confirmed by observed trends in bedload yield and particle mobility.
A Framework for Estimating the Probability Distribution of Event Runoff Coefficient in Ungauged Catchments
Authors: Zheng Yanchen , Coxon Gemma , Woods Ross , Li Jianzhu , Feng Ping
Published: December 2022

The derived distribution method is a promising approach for flood estimation in ungauged catchments. In this approach, event runoff coefficient (ERC) is often adopted to behave as the runoff generation component since the behavior of ERC is closely related to flood generation mechanisms and its distribution reflects catchment climatological and landscape characteristics. However, there is a lack of understanding of how to transfer the information on ERC characteristics from gauged to ungauged catchments at catchment scale. Hence, here, we propose a generalized framework to estimate the probability distribution of ERC for ungauged catchments based on knowledge of the spatial and temporal controls on ERC from gauged catchments. Key components of the framework include cluster analysis based on ERC characteristics, linking clusters with catchment attributes, and constructing typical probability distribution of ERC conditioned on its temporal indicators. A total of 290,743 rainfall‐runoff events observed in 431 GB catchments during the period 1990–2014 have been employed to verify the framework. Good estimations are obtained with the median value of coefficient of determination (R2) reaching 0.85 across all test catchments. The results indicate that similar pre‐event catchment conditions may cause distinct runoff response in different catchments, thus predicting the correct spatial cluster is crucial to the estimation accuracy. This work sheds light on constructing a stochastic generator model of ERC according to its spatial pattern and temporal dynamic, facilitating a new alternative for flood estimation method in ungauged catchments.
Planarized THz quantum cascade lasers for broadband coherent photonics
Authors: Senica Urban , Forrer Andres , Olariu Tudor , Micheletti Paolo , Cibella Sara , Torrioli Guido , Beck Mattias , Faist Jérôme , Scalari Giacomo
Published: December 2022

Recently, there has been a growing interest in integrated THz photonics for various applications in communications, spectroscopy and sensing. We present a new integrated photonic platform based on active and passive elements integrated in a double-metal, high-confinement waveguide layout planarized with a low-loss polymer. An extended top metallization keeps waveguide losses low while improving dispersion, thermal and RF properties, as it enables to decouple the design of THz and microwave cavities. Free-running on-chip quantum cascade laser combs spanning 800 GHz, harmonic states with over 1.1 THz bandwidth and RF-injected broadband incoherent states spanning over nearly 1.6 THz are observed using a homogeneous quantum-cascade active core. With a strong external RF drive, actively mode-locked pulses as short as 4.4 ps can be produced, as measured by SWIFTS. We demonstrate as well passive waveguides with low insertion loss, enabling the tuning of the laser cavity boundary conditions and the co-integration of active and passive elements on the same THz photonic chip.
Placebo and nocebo effects: from observation to harnessing and clinical application
Authors: Tu Yiheng , Zhang Libo , Kong Jian
Published: December 2022

Placebo and nocebo effects are salubrious benefits and negative outcomes attributable to non-specific symbolic components. Leveraging advanced experimental and analytical approaches, recent studies have elucidated complicated neural mechanisms that may serve as a solid basis for harnessing the powerful self-healing and self-harming capacities and applying these findings to improve medical practice and minimize the unintended exacerbation of symptoms in medical practice. We review advances in employing psychosocial, pharmacological, and neuromodulation approaches to modulate/harness placebo and nocebo effects. While these approaches show promising potential, translating these research findings into clinical settings still requires careful methodological, technical, and ethical considerations.
ALKBH5 promotes PD-L1-mediated immune escape through m6A modification of ZDHHC3 in glioma
Authors: Tang Wenhui , Xu Ningbo , Zhou Jian , He Zhenyan , Lenahan Cameron , Wang Chenyang , Ji Huangyi , Liu Boyang , Zou Yujiao , Zeng Huijun , Guo Hongbo
Published: December 2022

N6-methylation of adenosine (m6A) is one of the most frequent chemical modifications in eukaryotic RNAs and plays a vital role in tumorigenesis and progression. Recently, emerging studies have shown that m6A modification by ALKBH5 was associated with immunotherapy response in various types of cancer. However, whether m6A demethylases ALKBH5 participate in regulating the tumor immune microenvironment and the efficacy of immunotherapy in glioblastoma remain unknown. Here, we found that deletion of ALKBH5 significantly inhibited the growth of glioma allografts, rescued the antitumoral immune response, and increased cytotoxic lymphocyte infiltration and proinflammatory cytokines in CSF while significantly suppressing PD-L1 protein expression. m6A-methylated RNA immunoprecipitation sequencing and RNA sequencing identify ZDDHC3 as the direct target of ALKBH5. Mechanically, ALKBH5 deficiency impairs the YTHDF2-mediated stability of ZDHHC3 mRNA, thereby suppressing PD-L1 expression by accelerating PD-L1 degradation in glioma. In addition, genetic deletion or pharmacological inhibition of ALKBH5 with IOX1 enhances the therapeutic efficacy of anti-PD-1 treatment in preclinical mice models. These data suggest that the combination of anti-PD-1 therapy and ALKBH5 inhibition may be a promising treatment strategy in glioma.
Predicting recombination frequency from map distance
Authors: Kivikoski Mikko , Rastas Pasi , Löytynoja Ari , Merilä Juha
Published: December 2022

Map distance is one of the key measures in genetics and indicates the expected number of crossovers between two loci. Map distance is estimated from the observed recombination frequency using mapping functions, the most widely used of those, Haldane and Kosambi, being developed at the time when the number of markers was low and unobserved crossovers had a substantial effect on the recombination fractions. In contemporary high-density marker data, the probability of multiple crossovers between adjacent loci is negligible and different mapping functions yield the same result, that is, the recombination frequency between adjacent loci is equal to the map distance in Morgans. However, high-density linkage maps contain an interpretation problem: the map distance over a long interval is additive and its association with recombination frequency is not defined. Here, we demonstrate with high-density linkage maps from humans and stickleback fishes that the inverses of Haldane’s and Kosambi’s mapping functions systematically underpredict recombination frequencies from map distance. To remedy this, we formulate a piecewise function that yields more accurate predictions of recombination frequency from map distance. Our results demonstrate that the association between map distance and recombination frequency is context-dependent and without a universal solution.
Regulatory basis for reproductive flexibility in a meningitis-causing fungal pathogen
Authors: Hu Pengjie , Ding Hao , Liu Huimin , Yang Yulin , Chen Lei , He Guang-Jun , Ke Weixin , Zhu Ping , Tian Xiuyun , Peng Yan , Shen Zhenghao , Yao Xiaoxia , Tao Changyu , Yang Ence , Liao Guojian , Liu Xiao , Wang Linqi
Published: December 2022

Pathogenic fungi of the genusCryptococcuscan undergo two sexual cycles, involving either bisexual diploidization (after fusion of haploid cells of different mating type) or unisexual diploidization (by autodiploidization of a single cell). Here, we construct a gene-deletion library for 111 transcription factor genes inCryptococcus deneoformans, and explore the roles of these regulatory networks in the two reproductive modes. We show that transcription factors crucial for bisexual syngamy induce the expression of known mating determinants as well as other conserved genes of unknown function. Deletion of one of these genes, which we termFMP1, leads to defects in bisexual reproduction inC. deneoformans, its sister speciesCryptococcus neoformans, and the ascomyceteNeurospora crassa. Furthermore, we show that a recently evolved regulatory cascade mediates pre-meiotic unisexual autodiploidization, supporting that this reproductive process is a recent evolutionary innovation. Our findings indicate that genetic circuits with different evolutionary ages govern hallmark events distinguishing unisexual and bisexual reproduction inCryptococcus.
Molecular polariton electroabsorption
Authors: Cheng Chiao-Yu , Krainova Nina , Brigeman Alyssa N. , Khanna Ajay , Shedge Sapana , Isborn Christine , Yuen-Zhou Joel , Giebink Noel C.
Published: December 2022

We investigate electroabsorption (EA) in organic semiconductor microcavities to understand whether strong light-matter coupling non-trivially alters their nonlinear optical [$${\chi }^{(3)}\left(\omega,{{{{\mathrm{0,0}}}}}\right)$$

χ

(

3

)

ω
,
0, 0

] response. Focusing on strongly-absorbing squaraine (SQ) molecules dispersed in a wide-gap host matrix, we find that classical transfer matrix modeling accurately captures the EA response of low concentration SQ microcavities with a vacuum Rabi splitting of $$\hslash \Omega \approx 200$$
ℏ
Ω
≈
200
meV, but fails for high concentration cavities with $$\hslash \Omega \approx 420$$
ℏ
Ω
≈
420
meV. Rather than new physics in the ultrastrong coupling regime, however, we attribute the discrepancy at high SQ concentration to a nearly dark H-aggregate state below the SQ exciton transition, which goes undetected in the optical constant dispersion on which the transfer matrix model is based, but nonetheless interacts with and enhances the EA response of the lower polariton mode. These results indicate that strong coupling can be used to manipulate EA (and presumably other optical nonlinearities) from organic microcavities by controlling the energy of polariton modes relative to other states in the system, but it does not alter the intrinsic optical nonlinearity of the organic semiconductor inside the cavity.
A genome-wide CRISPR screen identifies WDFY3 as a regulator of macrophage efferocytosis
Authors: Shi Jianting , Wu Xun , Wang Ziyi , Li Fang , Meng Yujiao , Moore Rebecca M. , Cui Jian , Xue Chenyi , Croce Katherine R. , Yurdagul Arif , Doench John G. , Li Wei , Zarbalis Konstantinos S. , Tabas Ira , Yamamoto Ai , Zhang Hanrui
Published: December 2022

Phagocytic clearance of dying cells, termed efferocytosis, is essential for maintaining tissue homeostasis, yet our understanding of efferocytosis regulation remains incomplete. Here we perform a FACS-based, genome-wide CRISPR knockout screen in primary mouse macrophages to search for novel regulators of efferocytosis. The results show thatWdfy3knockout in macrophages specifically impairs uptake, but not binding, of apoptotic cells due to defective actin disassembly. Additionally, WDFY3 interacts with GABARAP, thus facilitating LC3 lipidation and subsequent lysosomal acidification to permit the degradation of apoptotic cell components. Mechanistically, while the C-terminus of WDFY3 is sufficient to rescue the impaired degradation induced byWdfy3knockout, full-length WDFY3 is required to reconstitute the uptake of apoptotic cells. Finally, WDFY3 is also required for efficient efferocytosis in vivo in mice and in vitro in primary human macrophages. This work thus expands our knowledge of the mechanisms of macrophage efferocytosis, as well as supports genome-wide CRISPR screen as a platform for interrogating complex functional phenotypes in primary macrophages.
Highly active and stable OER electrocatalysts derived from Sr2MIrO6 for proton exchange membrane water electrolyzers
Authors: Retuerto María , Pascual Laura , Torrero Jorge , Salam Mohamed Abdel , Tolosana-Moranchel Álvaro , Gianolio Diego , Ferrer Pilar , Kayser Paula , Wilke Vincent , Stiber Svenja , Celorrio Verónica , Mokthar Mohamed , Sanchez Daniel García , Gago Aldo Saul , Friedrich Kaspar Andreas , Peña Miguel Antonio , Alonso José Antonio , Rojas Sergio
Published: December 2022

Proton exchange membrane water electrolysis is a promising technology to produce green hydrogen from renewables, as it can efficiently achieve high current densities. Lowering iridium amount in oxygen evolution reaction electrocatalysts is critical for achieving cost-effective production of green hydrogen. In this work, we develop catalysts from Ir double perovskites. Sr2CaIrO6 achieves 10 mA cm−2 at only 1.48 V. The surface of the perovskite reconstructs when immersed in an acidic electrolyte and during the first catalytic cycles, resulting in a stable surface conformed by short-range order edge-sharing IrO6 octahedra arranged in an open structure responsible for the high performance. A proton exchange membrane water electrolysis cell is developed with Sr2CaIrO6 as anode and low Ir loading (0.4 mgIr cm−2). The cell achieves 2.40 V at 6 A cm−2 (overload) and no loss in performance at a constant 2 A cm−2 (nominal load). Thus, reducing Ir use without compromising efficiency and lifetime.
Guest-adaptive molecular sensing in a dynamic 3D covalent organic framework
Authors: Wei Lei , Sun Tu , Shi Zhaolin , Xu Zezhao , Wen Wen , Jiang Shan , Zhao Yingbo , Ma Yanhang , Zhang Yue-Biao
Published: December 2022

Molecular recognition is an attractive approach to designing sensitive and selective sensors for volatile organic compounds (VOCs). Although organic macrocycles and cages have been well-developed for recognising organics by their adaptive pockets in liquids, porous solids for gas detection require a deliberate design balancing adaptability and robustness. Here we report a dynamic 3D covalent organic framework (dynaCOF) constructed from an environmentally sensitive fluorophore that can undergo concerted and adaptive structural transitions upon adsorption of gas and vapours. The COF is capable of rapid and reliable detection of various VOCs, even for non-polar hydrocarbon gas under humid conditions. The adaptive guest inclusion amplifies the host-guest interactions and facilitates the differentiation of organic vapours by their polarity and sizes/shapes, and the covalently linked 3D interwoven networks ensure the robustness and coherency of the materials. The present result paves the way for multiplex fluorescence sensing of various VOCs with molecular-specific responses.
Inflammatory microbes and genes as potential biomarkers of Parkinson’s disease
Authors: Nie Shiqing , Wang Jichen , Deng Ye , Ye Zheng , Ge Yuan
Published: December 2022

As the second-largest neurodegenerative disease in the world, Parkinson’s disease (PD) has brought a severe economic and medical burden to our society. Growing evidence in recent years suggests that the gut microbiome may influence PD, but the exact pathogenesis of PD remains unclear. In addition, the current diagnosis of PD could be inaccurate and expensive. In this study, the largest meta-analysis currently of the gut microbiome in PD was analyzed, including 2269 samples by 16S rRNA gene and 236 samples by shotgun metagenomics, aiming to reveal the connection between PD and gut microbiome and establish a model to predict PD. The results showed that the relative abundances of potential pro-inflammatory bacteria, genes and pathways were significantly increased in PD, while potential anti-inflammatory bacteria, genes and pathways were significantly decreased. These changes may lead to a decrease in potential anti-inflammatory substances (short-chain fatty acids) and an increase in potential pro-inflammatory substances (lipopolysaccharides, hydrogen sulfide and glutamate). Notably, the results of 16S rRNA gene and shotgun metagenomic analysis have consistently identified five decreased genera (Roseburia, Faecalibacterium, Blautia, Lachnospira, and Prevotella) and five increased genera (Streptococcus, Bifidobacterium, Lactobacillus, Akkermansia, and Desulfovibrio) in PD. Furthermore, random forest models performed well for PD prediction based on 11 genera (accuracy > 80%) or 6 genes (accuracy > 90%) related to inflammation. Finally, a possible mechanism was presented to explain the pathogenesis of inflammation leading to PD. Our results provided further insights into the prediction and treatment of PD based on inflammation.
Alpha transcranial alternating current stimulation reduces depressive symptoms in people with schizophrenia and auditory hallucinations: a double-blind, randomized pilot clinical trial
Authors: Zhang Mengsen , Force Rachel B. , Walker Christopher , Ahn Sangtae , Jarskog L. Fredrik , Frohlich Flavio
Published: December 2022

People with schizophrenia exhibit reduced alpha oscillations and frontotemporal coordination of brain activity. Alpha oscillations are associated with top-down inhibition. Reduced alpha oscillations may fail to censor spurious endogenous activity, leading to auditory hallucinations. Transcranial alternating current stimulation (tACS) at the alpha frequency was shown to enhance alpha oscillations in people with schizophrenia and may thus be a network-based treatment for auditory hallucinations. We conducted a double-blind, randomized, placebo-controlled pilot clinical trial to examine the efficacy of 10-Hz tACS in treating auditory hallucinations in people with schizophrenia. 10-Hz tACS was administered in phase at the dorsolateral prefrontal cortex and the temporoparietal junction with a return current at Cz. Patients were randomized to receive tACS or sham for five consecutive days during the treatment week (40 min/day), followed by a maintenance period, during which participants received weekly tACS (40 min/visit) or sham. tACS treatment reduced general psychopathology (p < 0.05, Cohen’s d = −0.690), especially depression (p < 0.005, Cohen’s d = −0.806), but not auditory hallucinations. tACS treatment increased alpha power in the target region (p < 0.05), increased the frequency of peak global functional connectivity towards 10 Hz (p < 0.05), and reduced left-right frontal functional connectivity (p < 0.005). Importantly, changes in brain functional connectivity significantly correlated with symptom improvement (p < 0.05). Daily 10 Hz-tACS increased alpha power and altered alpha-band functional connectivity. Successful target engagement reduced depression and other general psychopathology symptoms, but not auditory hallucinations. Considering existing research of 10Hz tACS as a treatment for major depressive disorder, our study demonstrates its transdiagnostic potential for treating depression.
CloudSEN12, a global dataset for semantic understanding of cloud and cloud shadow in Sentinel-2
Authors: Aybar Cesar , Ysuhuaylas Luis , Loja Jhomira , Gonzales Karen , Herrera Fernando , Bautista Lesly , Yali Roy , Flores Angie , Diaz Lissette , Cuenca Nicole , Espinoza Wendy , Prudencio Fernando , Llactayo Valeria , Montero David , Sudmanns Martin , Tiede Dirk , Mateo-García Gonzalo , Gómez-Chova Luis
Published: December 2022

Accurately characterizing clouds and their shadows is a long-standing problem in the Earth Observation community. Recent works showcase the necessity to improve cloud detection methods for imagery acquired by the Sentinel-2 satellites. However, the lack of consensus and transparency in existing reference datasets hampers the benchmarking of current cloud detection methods. Exploiting the analysis-ready data offered by the Copernicus program, we created CloudSEN12, a new multi-temporal global dataset to foster research in cloud and cloud shadow detection. CloudSEN12 has 49,400 image patches, including (1) Sentinel-2 level-1C and level-2A multi-spectral data, (2) Sentinel-1 synthetic aperture radar data, (3) auxiliary remote sensing products, (4) different hand-crafted annotations to label the presence of thick and thin clouds and cloud shadows, and (5) the results from eight state-of-the-art cloud detection algorithms. At present, CloudSEN12 exceeds all previous efforts in terms of annotation richness, scene variability, geographic distribution, metadata complexity, quality control, and number of samples.
Micronutrients deficiencies and its correlation with the soil-transmitted helminthic infections among children and non-pregnant women in Nepal: findings from Nepal national micronutrient status survey
Authors: Mehata Suresh , Parajuli Kedar Raj , Rayamajhee Binod , Yadav Uday Narayan , Mehta Ranju Kumari , Singh Dipendra Raman
Published: December 2022

Despite having a high risk of soil-transmitted helminths (STHs) infection, no national level study has been conducted to assess incidence and correlates of STHs in Nepal. Thus, we hypothesized that micronutrients and social status are linked with incidence of STHs infection among 6–59 months children and 15–49 years non-pregnant women in Nepal and Kato-Katz technique was adopted to measure the type and intensity of STHs infections using fresh stool specimens and venous blood was used to examine micronutrients biomarkers. Anthropometric measurements such as height and weight, sociodemographic and health status were determined using structured questionnaire. Logistic regression was used to assess unadjusted and adjusted odds ratio (AOR) and the 95% CIs of ORs. The bivariate association of STHs was assessed with the covariates variables. Overall, 12% children and 19% non-pregnant women had STHs infection; A. lumbricoides was the predominant helminth in both study participants. In multivariate model; age, ethnicity, anaemia and zinc deficiency were associated with STHs infections in children. Similarly, higher odds of STHs occurrence was observed among non-pregnant women with vitamin A deficiency. Findings from this study suggest that high-risk population, with a focus on those of lower socioeconomic status should be on priority of deworming program, nutrition intervention, and mass administration of preventive chemotherapy and sanitation champions supplement to reduce the STHs infections in Nepal.
Dietary supplement mislabelling: case study on selected slimming products by developing a green isocratic HPLC method for their quality control
Authors: El Azab Noha F. , Abdelaal Sarah H. , Hassan Said A. , El-Kosasy Amira M.
Published: December 2022

Nowadays, a huge population consumes Dietary supplements for losing weight. Products are often claimed as botanical blends, yet they aren't necessarily safe. Misleading labels are also very common. Thus, validated analytical methods for a wide range of slimming compounds are highly needed. Herein, we present a simple HPLC/PDA method for the quantitation of seven popular slimming ingredients. Studied compounds were Caffeine, Raspberry Ketone, trans-Resveratrol, p-Synephrine, p-Octopamine, p-Hordenine and 2-phenethylamine. After optimization, separation was carried out on a C18 column and mobile phase was a mixture of Acetonitrile:Water containing 0.1% phosphoric acid (50:50, %v/v). The last compound was eluted at 9.76 min. Separation was efficient showing baseline- separated symmetric peaks, without using any gradient programs, organic mobile phase modifiers or modified stationary phases. Method validation was done following ICH guidelines. Calibration curves were linear over wide concentration ranges and calculated LOD values were in the range 0.02–0.09 µg/mL. Method greenness was assessed using Analytical Eco-scale, GAPI and AGREE metric tools. Further, four random sample products purchased from online supplement stores were assayed. Results proved some mislabeling actions. To support our findings, standard addition was carried out and average % recoveries were 96.67 – 101.44% with standard deviation ≤ 2.83 between measurements.