bluuebunny/crossref_metadata_2025 huggingface dataset:
Observations of Winds and CMEs of Low-Mass Stars
Authors: Osten Rachel A.
Published: August 2023

In this invited review talk I summarize some of the recent observational advances in understanding mass loss from low-mass stars. This can take the form of a relatively steady wind, or stochastically occurring coronal mass ejections (CMEs). In recent years, there has been an expansion of observational signatures used to probe mass loss in low-mass stars. These observational tools span the electromagnetic spectrum. There has also been a resurgence of interest in this topic because of its potential impact on exoplanet space weather and habitability. The numerous recent observational and theoretical results also point to the complexities involved, rather than using simple scalings from solar understanding. This underscores the need to understand reconnection and eruption processes on magnetically active stars as a tool to putting our Sun in context.
X-ray view of colliding winds in WR 25
Authors: Arora Bharti , Pandey Jeewan C. , De Becker Michaël
Published: August 2023

Astract

The long-term behavior of a colliding wind binary WR 25 is presented using archival X-ray data obtained over a time span of : 16 years. The present analysis reveals phase-locked variations repeating consistently over many consecutive orbits of the source (with binary orbital period : 208 days). A significant deviation of the X-ray flux with respect to the theoretical 1/D trend (D is the binary separation) close to periastron passage has been observed. This may occur due to the shifting of the adiabatic wind collision to the radiative regime in that part of the orbit. Further, no signature of X-ray emission in 10.0-79.0 keV energy range attributable to inverse Compton scattering is detected by NuSTAR.
Spin-down and reduced mass loss in early-type stars with large-scale magnetic fields
Authors: Keszthelyi Z. , de Koter A. , Götberg Y. , Meynet G. , Brands S.A. , Petit V. , Carrington M. , David-Uraz A. , Geen S.T. , Georgy C. , Hirschi R. , Puls J. , Ramalatswa K.J. , Shultz M.E. , ud-Doula A.
Published: August 2023

Magnetism can greatly impact the evolution of stars. In some stars with OBA spectral types there is direct evidence via the Zeeman effect for stable, large-scale magnetospheres, which lead to the spin-down of the stellar surface and reduced mass loss. So far, a comprehensive grid of stellar structure and evolution models accounting for these effects was lacking. For this reason, we computed and studied models with two magnetic braking and two chemical mixing schemes in three metallicity environments with the mesa software instrument. We find notable differences between the subgrids, which affects the model predictions and thus the detailed characterisation of stars. We are able to quantify the impact of magnetic fields in terms of preventing quasi-chemically homogeneous evolution and producing slowly-rotating, nitrogen-enriched (“Group 2”) stars. Our model grid is fully open access and open source.
Discrete Absorption Components from 3-D spot models of hot star winds
Authors: Driessen F. A. , Kee N. D.
Published: August 2023

The winds of hot, massive stars are variable from processes happening on both large and small spatial scales. A particular case of such wind variability is ‘discrete-absorption components’ (DACs) that manifest themselves as outward moving density features in UV resonance line spectra. Such DACs are believed to be caused by large-scale spiral-shaped density structures in the stellar wind. We consider novel 3-D radiation-hydrodynamic models of rotating hot star winds and study the emergence of co-rotating spiral structures due to a local (pseudo-)magnetic spot on the stellar surface. Subsequently, the hydrodynamic models are used to retrieve DAC spectral signatures in synthetic UV spectra created from a 3-D short-characteristics radiative transfer code.
ISOSCELES: Grid of stellar atmosphere and hydrodynamic models of massive stars. The first results
Authors: Araya Ignacio , Curé Michel , Machuca Natalia , Arcos Catalina
Published: August 2023

In this work we seek to derive simultaneously the stellar and wind parameters of massive stars, mainly A and B type supergiant stars. Our stellar properties encompass the effective temperature, the surface gravity, the micro-turbulence velocity and, silicon abundance. For wind properties we consider the line–force parameters (α, k and δ) obtained from the standard line-driven wind theory. To model the data we use the radiative transport code Fastwind considering the hydrodynamic solutions derived with the stationary code Hydwind. Then, ISOSCELES, a grid of stellar atmosphere and hydrodynamic models of massive stars is created. Together with the observed spectra and a semi-automatic tool the physical properties from these stars are determined through spectral line fittings. This quantitative spectroscopic analysis provide an estimation about the line–force parameters. In addition, we confirm that the hydrodynamic solutions, called δ-slow solutions, describe quite reliable the radiation line-driven winds of B supergiant stars.
Effect of stellar flares and coronal mass ejections on the atmospheric escape from hot Jupiters
Authors: Hazra Gopal , Vidotto Aline A. , Carolan Stephen , Villarreal D’Angelo Carolina , Manchester Ward
Published: August 2023

Spectral observations in the Ly-α line have shown that atmospheric escape is variable and for the exoplanet HD189733b, the atmospheric evaporation goes from undetected to enhanced evaporation in a 1.5 years interval. To understand the temporal variation in the atmospheric escape, we investigate the effect of flares, winds, and CMEs on the atmosphere of hot Jupiter HD189733b using 3D self-consistent radiation hydrodynamic simulations. We consider four cases: first, the quiescent phase including stellar wind; secondly, a flare; thirdly, a CME; and fourthly, a flare followed by a CME. We find that the flare alone increases the atmospheric escape rate by only 25%, while the CME leads to a factor of 4 increments, in comparison to the quiescent case. We also find that the flare alone cannot explain the observed high blue-shifted velocities seen in the Ly-α. The CME, however, leads to an increase in the velocity of escaping atmospheres, enhancing the blue-shifted transit depth.
Observations of outflows of massive stars
Authors: Mehner Andrea
Published: August 2023

Mass loss plays a key role in the evolution of massive stars and their environment. High mass-loss events are traced by complex circumstellar ejecta and intricate line profiles across the upper Hertzsprung-Russell diagram for massive stars in different evolutionary stages. The basic physics of radiation-driven stellar wind for hot stars is well understood. However, the driving mechanisms and related instabilities for their enhanced mass-loss episodes and the driving mechanisms for the mass loss of cool stars are still debated. In this review, the mass-loss characteristics and the possible mechanisms will be surveyed for an observational set of prominent massive stellar populations that experience outflows, strong stellar winds, and periods of enhanced and eruptive mass loss; massive young stellar objects, OB-type stars, red supergiants, warm hypergiants, luminous blue variables, and Wolf-Rayet stars.
Short-term variations of surface magnetism and prominences of the young sun-like star V530 Per
Authors: Tianqi Cang , Petit Pascal , Donati Jean-François , Folsom Colin
Published: August 2023

V530 Per is a solar-like member of the young open cluster α Persei, with an ultra-short rotation period (P∼0.32d). We report on two spectropolarimetric campaigns using ESPaDOnS, aimed at characterizing the short-term variability of its magnetic activity and large-scale magnetic field. We used time-resolved spectropolarimetric observations obtained in 2006 and 2018 and reconstructed the brightness distribution and large-scale magnetic field geometry of V530 Per through Zeeman-Doppler imaging. Using the same data sets, we also mapped the spatial distribution of prominences through tomography of Hα emission. We reconstruct, at both epochs, a large, dark spot occupying the polar region of V530 Per while smaller (dark and bright) spots were reconstructed at lower latitudes. The maximal field strength reached ∼1 kG. The prominence pattern displayed a stable component that was confined close to the corotation radius. In 2018, we also observed rapidly evolving Hα emitting structures, over timescales ranging from minutes to days. The fast Hα evolution was not linked to any detected photospheric changes in the spot or magnetic coverage.
Stellar wind from low-mass main-sequence stars: an overview of theoretical models
Authors: Shoda Munehito
Published: August 2023

The stellar wind from low-mass stars affects the evolution of the whole stellar system in various ways. To better describe its quantitative contributions, we need to understand the theoretical aspects of stellar wind formation. Here, we present an overview of the theoretical models of stellar wind. The classical thermally-driven wind model fails in reproducing the anti-correlation between the coronal temperature and wind speed observed in the solar wind, thus needs modification with magnetic-energy injection. Specifically, energy input by Alfvén wave is likely to be important. Indeed, a number of solar-wind observations are well reproduced by the Alfvén-wave models, although it could be risky to directly apply the Alfvén-wave models to general low-mass stars. For a better description of stellar wind from low-mass stars with a variety of activity levels, the hybrid model would be better, in which we consider the effect of flux emergence as well as Alfvén wave.
Double tail structure in escaping atmospheres of magnetised close-in planets
Authors: Vidotto A. A. , Carolan S. , Hazra G. , Villarreal D’Angelo C. , Kubyshkina D.
Published: August 2023

High-energy stellar irradiation can photoevaporate planetary atmospheres, which can be observed in spectroscopic transits of hydrogen lines. Here, we investigate the effect of planetary magnetic fields on the observational signatures of atmospheric escape in hot Jupiters.
Clumping and X-rays in cool B Supergiants
Authors: Bernini-Peron Matheus , Marcolino W. L. F. , Sander A. A. C.
Published: August 2023

B supergiants (BSGs) are evolved objects on the cool end of the line-driven wind regime. Studying their atmospheres provides important insights on the stellar wind physics of these objects and their evolutionary status. So far important features of their spectra, especially in the UV region, could not be reproduced consistently with atmosphere models. This translates directly into problems of our understanding of their wind properties. Here, we present new insights about the BSGs on the cooler side of the Bi-Stability Jump, corresponding to spectral types later than B1. Using UV and optical data, we analysed a sample of Galactic cool BSGs. Including for the first time X-rays and clumping the wind models, we show that the spectra of cool BSGs cannot be explained without X-rays, despite any clear detection of the target stars.
On the making of a PN: the interaction of a multiple stellar wind with the ISM
Authors: Manchado Arturo , Villaver Eva , García-Segura G. , Bianchi Luciana
Published: August 2023

NGC 7293, the Helix nebula, represents one of the rare instances in which theoretical predictions of stellar evolution can be accurately tested against observations since the precise parallax distance and the velocity and proper motion of the star are well known. We present numerical simulations of the formation of the Helix PN that are fully constrained by the progenitor stellar mass, stellar evolution history, and star-interstellar medium (ISM) interaction. In the simulations, multiple bow-shock structures are formed by fragmentation of the shock front where the direct interaction of the stellar wind with the ISM takes place.
Statistical properties of cold circumstellar envelops observed in NESS–NRO
Authors: Amada K. , Fukaya S. , Imai H. , Scicluna P. , Hirano N. , Trejo-Cruz A. , Zeegers S. , Kemper F. , Srinivasan S. , Wallström S. , Dharmawardena T. , Shinnaga H.
Published: August 2023

We conducted CO J=1→0 emission line observations for nearby AGB stars using the Nobeyama 45 m telescope. Comparing our results with those from CO J=3→2 observations with JCMT, the circumstellar envelopes observed in CO J=1→0 look more extended than J=3→2. Thus, we could trace the outer, cold parts of the envelopes. We also found four stars in which the CO/13CO ratio changes dramatically outward, but the change implies the effect of selective photodissociation by interstellar ultraviolet radiation, not the third dredge up in the stellar interior. We moreover found two unique stars with aspherical envelope morphology.
Agricultural Research Service Weed Science Research: Past, Present, and Future
Authors: Young Stephen L. , Anderson James V. , Baerson Scott R. , Bajsa-Hirschel Joanna , Blumenthal Dana M. , Boyd Chad S. , Boyette Clyde D. , Brennan Eric B. , Cantrell Charles L. , Chao Wun S. , Chee-Sanford Joanne C. , Clements Charlie D. , Dray F. Allen , Duke Stephen O. , Eason Kayla M. , Fletcher Reginald S. , Fulcher Michael R. , Gaskin John F. , Grewell Brenda J. , Hamerlynck Erik P. , Hoagland Robert E. , Horvath David P. , Law Eugene P. , Madsen John D. , Martin Daniel E. , Mattox Clint , Mirsky Steven B. , Molin William T. , Moran Patrick J. , Mueller Rebecca C. , Nandula Vijay K. , Newingham Beth A. , Pan Zhiqiang , Porensky Lauren M. , Pratt Paul D. , Price Andrew J. , Rector Brian G. , Reddy Krishna N. , Sheley Roger L. , Smith Lincoln , Smith Melissa C. , Snyder Keirith A. , Tancos Matthew A. , West Natalie M. , Wheeler Gregory S. , Williams Martin M. , Wolf Julie , Wonkka Carissa L. , Wright Alice A. , Xi Jing , Ziska Lew H.
Published: August 2023

The U.S. Department of Agriculture–Agricultural Research Service (USDA-ARS) has been a leader in weed science research covering topics ranging from the development and use of integrated weed management (IWM) tactics to basic mechanistic studies, including biotic resistance of desirable plant communities and herbicide resistance. ARS weed scientists have worked in agricultural and natural ecosystems, including agronomic and horticultural crops, pastures, forests, wild lands, aquatic habitats, wetlands, and riparian areas. Through strong partnerships with academia, state agencies, private industry, and numerous federal programs, ARS weed scientists have made contributions to discoveries in the newest fields of robotics and genetics, as well as the traditional and fundamental subjects of weed–crop competition and physiology and integration of weed control tactics and practices. Weed science at ARS is often overshadowed by other research topics; thus, few are aware of the long history of ARS weed science and its important contributions. This review is the result of a symposium held at the Weed Science Society of America’s 62nd Annual Meeting in 2022 that included 10 separate presentations in a virtual Weed Science Webinar Series. The overarching themes of management tactics (IWM, biological control, and automation), basic mechanisms (competition, invasive plant genetics, and herbicide resistance), and ecosystem impacts (invasive plant spread, climate change, conservation, and restoration) represent core ARS weed science research that is dynamic and efficacious and has been a significant component of the agency’s national and international efforts. This review highlights current studies and future directions that exemplify the science and collaborative relationships both within and outside ARS. Given the constraints of weeds and invasive plants on all aspects of food, feed, and fiber systems, there is an acknowledged need to face new challenges, including agriculture and natural resources sustainability, economic resilience and reliability, and societal health and well-being.
The Observed Effects of Cold Pools on Convection Triggering and Organization During DYNAMO/AMIE
Authors: Sakaeda Naoko , Torri Giuseppe
Published: August 2023

Cold pools that form from existing convection can generate new clouds nearby, a process that has been suggested to contribute to cloud organization. However, some disagreement exists on the role of cold pools in cloud organization over tropical oceans, and much remains to be understood on how this role depends on the state of large‐scale disturbances such as the Madden‐Julian Oscillation (MJO). This study addresses this question by examining the intraseasonal variability in the properties of cold pools and their effects on convection triggering using observations. The unique set of surface meteorology data and ground‐based radars deployed during the DYNAMO/AMIE field campaign are used to identify cold pools and the associated spatiotemporal evolution of rainfall. The results suggest that cold pools enhance rainfall at their expected speed of 3–8 m s−1, which includes the Doppler‐shifting effect by the background wind. The cold pools also enhance rainfall mainly within a 20 km radius, especially in the direction of boundary‐layer vertical wind shear. However, gravity waves appear to contribute predominantly to the propagation of convection over a wider range of distances due to their faster propagation speeds. The interface of convection triggering and propagation at different speeds of cold pools and gravity waves seems to contribute to cloud organization. The effectiveness of cold pools and gravity waves on cloud organization also depends highly on the MJO due to the combined effects of changes in environmental humidity and boundary to lower‐tropospheric wind.
Cell fate determinant Llgl1 is required for propagation of acute myeloid leukemia
Authors: Eifert Theresa , Hsu Chen-Jen , Becker Alicia L. , Graessle Sarah , Horne Arik , Bemmann Franziska , Zhang Qirui , Heuser Michael , Vasioukhin Valeri , Scholl Sebastian , Hochhaus Andreas , Siegerist Florian , Endlich Nicole , Bullinger Lars , Lane Steven W. , Haas Simon , Schnoeder Tina M. , Heidel Florian H.
Published: August 2023

Scribble complex proteins can influence cell fate decisions and self-renewal capacity of hematopoietic cells. While specific cellular functions of Scribble complex members are conserved in mammalian hematopoiesis, they appear to be highly context dependent. Using CRISPR/Cas9-based genetic screening, we have identified Scribble complex-related liabilities in AML including LLGL1. Despite its reported suppressive function in HSC self-renewal, inactivation of LLGL1 in AML confirms its relevant role for proliferative capacity and development of AML. Its function was conserved in human and murine models of AML and across various genetic backgrounds. Inactivation of LLGL1 results in loss of stemness-associated gene-expression including HoxA-genes and induces a GMP-like phenotype in the leukemia stem cell compartment. Re-expression of HoxA9 facilitates functional and phenotypic rescue. Collectively, these data establish LLGL1 as a specific dependency and putative target in AML and emphasizes its cell-type specific functions.
Metformin escape in prostate cancer by activating the PTGR1 transcriptional program through a novel super-enhancer
Authors: Ye Jianheng , Cai Shanghua , Feng Yuanfa , Li Jinchuang , Cai Zhiduan , Deng Yulin , Liu Ren , Zhu Xuejin , Lu Jianming , Zhuo Yangjia , Liang Yingke , Xie Jianjiang , Zhang Yanqiong , He Huichan , Han Zhaodong , Jia Zhenyu , Zhong Weide
Published: August 2023

The therapeutic efficacy of metformin in prostate cancer (PCa) appears uncertain based on various clinical trials. Metformin treatment failure may be attributed to the high frequency of transcriptional dysregulation, which leads to drug resistance. However, the underlying mechanism is still unclear. In this study, we found evidences that metformin resistance in PCa cells may be linked to cell cycle reactivation. Super-enhancers (SEs), crucial regulatory elements, have been shown to be associated with drug resistance in various cancers. Our analysis of SEs in metformin-resistant (MetR) PCa cells revealed a correlation with Prostaglandin Reductase 1 (PTGR1) expression, which was identified as significantly increased in a cluster of cells with metformin resistance through single-cell transcriptome sequencing. Our functional experiments showed that PTGR1 overexpression accelerated cell cycle progression by promoting progression from the G0/G1 to the S and G2/M phases, resulting in reduced sensitivity to metformin. Additionally, we identified key transcription factors that significantly increase PTGR1 expression, such as SRF and RUNX3, providing potential new targets to address metformin resistance in PCa. In conclusion, our study sheds new light on the cellular mechanism underlying metformin resistance and the regulation of the SE-TFs-PTGR1 axis, offering potential avenues to enhance metformin’s therapeutic efficacy in PCa.
Candidatus Nemesobacterales is a sponge-specific clade of the candidate phylum Desulfobacterota adapted to a symbiotic lifestyle
Authors: Gavriilidou Asimenia , Avcı Burak , Galani Anastasia , Schorn Michelle A , Ingham Colin J , Ettema Thijs J G , Smidt Hauke , Sipkema Detmer
Published: August 2023

Members of the candidate phylum Dadabacteria, recently reassigned to the phylum Candidatus Desulfobacterota, are cosmopolitan in the marine environment found both free-living and associated with hosts that are mainly marine sponges. Yet, these microorganisms are poorly characterized, with no cultured representatives and an ambiguous phylogenetic position in the tree of life. Here, we performed genome-centric metagenomics to elucidate their phylogenomic placement and predict the metabolism of the sponge-associated members of this lineage. Rank-based phylogenomics revealed several new species and a novel family (Candidatus Spongomicrobiaceae) within a sponge-specific order, named here Candidatus Nemesobacterales. Metabolic reconstruction suggests that Ca. Nemesobacterales are aerobic heterotrophs, capable of synthesizing most amino acids, vitamins and cofactors and degrading complex carbohydrates. We also report functional divergence between sponge- and seawater-associated metagenome-assembled genomes. Niche-specific adaptations to the sponge holobiont were evident from significantly enriched genes involved in defense mechanisms against foreign DNA and environmental stressors, host-symbiont interactions and secondary metabolite production. Fluorescence in situ hybridization gave a first glimpse of the morphology and lifestyle of a member of Ca. Desulfobacterota. Candidatus Nemesobacterales spp. were found both inside sponge cells centred around sponge nuclei and in the mesohyl of the sponge Geodia barretti. This study sheds light on the enigmatic group Ca. Nemesobacterales and their functional characteristics that reflect a symbiotic lifestyle.
Color stability of nanohybrid and microhybrid composites after immersion in common coloring beverages at different times: a laboratory study
Authors: Al-Shami Ahlam Mohammad , Alshami Mohammad Ali , Al-Kholani Abdulwahab I. , Al-Sayaghi Amat-Alkhaliq Mohammad
Published: August 2023

Objective/Aim

This in vitro study aimed to evaluate the color stability of microhybrid and nanohybrid restorative composites after exposure to immersion media common in Yemen for different periods.

Materials and methods

Two composite materials, nanohybrid Tetric N-Ceram and microhybrid Te-Econom Plus, were investigated. Six groups of 30 cylindrical specimens (n = 5/group; diameter, 10 mm; thickness, 2 mm; shade A2) of each restorative material were immersed for 1 week in distilled water, qat solution, Yemeni coffee, traditional Yemeni coffee (qishr), red tea, and Dilsi cola. Color changes were evaluated by colorimetry. The color data and pH were measured before and 1, 3, and 7 days after immersion. The data were statistically analyzed.

Results

Tetric N-Ceram showed lesser discoloration than did Te-Econom Plus. Qat, coffee, and red tea caused highly significant discoloration than did Dilsi cola and distilled water (p < 0.05). The role of low pH in discoloration depended on the colorant.

Discussion

Nanohybrid Tetric N-Ceram composites are more resistant to discoloration than are microhybrid Te-Econom Plus composites. Qat and coffee have the highest effect on composite discoloration.

Conclusions

These findings will aid in selecting composite materials and patient instruction.
Platelet-derived exerkine CXCL4/platelet factor 4 rejuvenates hippocampal neurogenesis and restores cognitive function in aged mice
Authors: Leiter Odette , Brici David , Fletcher Stephen J. , Yong Xuan Ling Hilary , Widagdo Jocelyn , Matigian Nicholas , Schroer Adam B. , Bieri Gregor , Blackmore Daniel G. , Bartlett Perry F. , Anggono Victor , Villeda Saul A. , Walker Tara L.
Published: August 2023

The beneficial effects of physical activity on brain ageing are well recognised, with exerkines, factors that are secreted into the circulation in response to exercise, emerging as likely mediators of this response. However, the source and identity of these exerkines remain unclear. Here we provide evidence that an anti-geronic exerkine is secreted by platelets. We show that platelets are activated by exercise and are required for the exercise-induced increase in hippocampal precursor cell proliferation in aged mice. We also demonstrate that increasing the systemic levels of the platelet-derived exerkine CXCL4/platelet factor 4 (PF4) ameliorates age-related regenerative and cognitive impairments in a hippocampal neurogenesis-dependent manner. Together these findings highlight the role of platelets in mediating the rejuvenating effects of exercise during physiological brain ageing.
Toward a formal theory for computing machines made out of whatever physics offers
Authors: Jaeger Herbert , Noheda Beatriz , van der Wiel Wilfred G.
Published: August 2023

Approaching limitations of digital computing technologies have spurred research in neuromorphic and other unconventional approaches to computing. Here we argue that if we want to engineer unconventional computing systems in a systematic way, we need guidance from a formal theory that is different from the classical symbolic-algorithmic Turing machine theory. We propose a general strategy for developing such a theory, and within that general view, a specific approach that we call fluent computing. In contrast to Turing, who modeled computing processes from a top-down perspective as symbolic reasoning, we adopt the scientific paradigm of physics and model physical computing systems bottom-up by formalizing what can ultimately be measured in a physical computing system. This leads to an understanding of computing as the structuring of processes, while classical models of computing systems describe the processing of structures.
IRX2 regulates angiotensin II-induced cardiac fibrosis by transcriptionally activating EGR1 in male mice
Authors: Ma Zhen-Guo , Yuan Yu-Pei , Fan Di , Zhang Xin , Teng Teng , Song Peng , Kong Chun-Yan , Hu Can , Wei Wen-Ying , Tang Qi-Zhu
Published: August 2023

Cardiac fibrosis is a common feature of chronic heart failure. Iroquois homeobox (IRX) family of transcription factors plays important roles in heart development; however, the role of IRX2 in cardiac fibrosis has not been clarified. Here we report that IRX2 expression is significantly upregulated in the fibrotic hearts. Increased IRX2 expression is mainly derived from cardiac fibroblast (CF) during the angiotensin II (Ang II)-induced fibrotic response. Using two CF-specific Irx2-knockout mouse models, we show that deletion of Irx2 in CFs protect against pathological fibrotic remodelling and improve cardiac function in male mice. In contrast, Irx2 gain of function in CFs exaggerate fibrotic remodelling. Mechanistically, we find that IRX2 directly binds to the promoter of the early growth response factor 1 (EGR1) and subsequently initiates the transcription of several fibrosis-related genes. Our study provides evidence that IRX2 regulates the EGR1 pathway upon Ang II stimulation and drives cardiac fibrosis.
Crackling noise microscopy
Authors: Nguyen Cam-Phu Thi , Schoenherr Peggy , Salje Ekhard K. H. , Seidel Jan
Published: August 2023

Crackling noise is a scale-invariant phenomenon found in various driven nonlinear dynamical material systems as a response to external stimuli such as force or external fields. Jerky material movements in the form of avalanches can span many orders of magnitude in size and follow universal scaling rules described by power laws. The concept was originally studied as Barkhausen noise in magnetic materials and now is used in diverse fields from earthquake research and building materials monitoring to fundamental research involving phase transitions and neural networks. Here, we demonstrate a method for nanoscale crackling noise measurements based on AFM nanoindentation, where the AFM probe can be used to study the crackling of individual nanoscale features, a technique we call crackling noise microscopy. The method is successfully applied to investigate the crackling of individual topological defects, i.e. ferroelectric domain walls. We show that critical exponents for avalanches are altered at these nanoscale features, leading to a suppression of mixed-criticality, which is otherwise present in domains. The presented concept opens the possibility of investigating the crackling of individual nanoscale features in a wide range of material systems.
National quantifications of methane emissions from fuel exploitation using high resolution inversions of satellite observations
Authors: Shen Lu , Jacob Daniel J. , Gautam Ritesh , Omara Mark , Scarpelli Tia R. , Lorente Alba , Zavala-Araiza Daniel , Lu Xiao , Chen Zichong , Lin Jintai
Published: August 2023

Reducing methane emissions from fossil fuel exploitation (oil, gas, coal) is an important target for climate policy, but current national emission inventories submitted to the United Nations Framework Convention on Climate Change (UNFCCC) are highly uncertain. Here we use 22 months (May 2018-Feb 2020) of satellite observations from the TROPOMI instrument to better quantify national emissions worldwide by inverse analysis at up to 50 km resolution. We find global emissions of 62.7 ± 11.5 (2σ) Tg a−1 for oil-gas and 32.7 ± 5.2 Tg a−1 for coal. Oil-gas emissions are 30% higher than the global total from UNFCCC reports, mainly due to under-reporting by the four largest emitters including the US, Russia, Venezuela, and Turkmenistan. Eight countries have methane emission intensities from the oil-gas sector exceeding 5% of their gas production (20% for Venezuela, Iraq, and Angola), and lowering these intensities to the global average level of 2.4% would reduce global oil-gas emissions by 11 Tg a−1 or 18%.
Genome-wide association studies reveal novel loci associated with pyrethroid and organophosphate resistance in Anopheles gambiae and Anopheles coluzzii
Authors: Lucas Eric R. , Nagi Sanjay C. , Egyir-Yawson Alexander , Essandoh John , Dadzie Samuel , Chabi Joseph , Djogbénou Luc S. , Medjigbodo Adandé A. , Edi Constant V. , Kétoh Guillaume K. , Koudou Benjamin G. , Van’t Hof Arjen E. , Rippon Emily J. , Pipini Dimitra , Harding Nicholas J. , Dyer Naomi A. , Cerdeira Louise T. , Clarkson Chris S. , Kwiatkowski Dominic P. , Miles Alistair , Donnelly Martin J. , Weetman David
Published: August 2023

Resistance to insecticides in Anopheles mosquitoes threatens the effectiveness of malaria control, but the genetics of resistance are only partially understood. We performed a large scale multi-country genome-wide association study of resistance to two widely used insecticides: deltamethrin and pirimiphos-methyl, using sequencing data from An. gambiae and An. coluzzii from ten locations in West Africa. Resistance was highly multi-genic, multi-allelic and variable between populations. While the strongest and most consistent association with deltamethrin resistance came from Cyp6aa1, this was based on several independent copy number variants (CNVs) in An. coluzzii, and on a non-CNV haplotype in An. gambiae. For pirimiphos-methyl, signals included Ace1, cytochrome P450s, glutathione S-transferases and the nAChR target site of neonicotinoid insecticides. The regions around Cyp9k1 and the Tep family of immune genes showed evidence of cross-resistance to both insecticides. These locally-varying, multi-allelic patterns highlight the challenges involved in genomic monitoring of resistance, and may form the basis for improved surveillance methods.
Comparison of the relative impacts of acute consumption of an inulin-enriched diet, milk kefir or a commercial probiotic product on the human gut microbiome and metabolome
Authors: Walsh Liam H. , Walsh Aaron M. , Garcia-Perez Isabel , Crispie Fiona , Costabile Adele , Ellis Richard , Finlayson Jim , Finnegan Laura A. , Claesson Marcus J. , Holmes Elaine , Cotter Paul D.
Published: August 2023

It has been established that the human gut microbiota is central to health, and, consequently, there has been a growing desire to positively modulate its composition and/or function through, for example, the use of fermented foods, prebiotics or probiotics. Here, we compare the relative impact of the daily consumption of an inulin-enriched diet (n = 10), a commercial probiotic-containing fermented milk product (FMP) (n = 10), or a traditional kefir FMP (n = 9), over a 28-day period on the gut microbiome and urine metabolome of healthy human adults. None of the treatments resulted in significant changes to clinical parameters or biomarkers tested. However, shotgun metagenomic analysis revealed that kefir consumption resulted in a significant change in taxonomy, in the form of an increased abundance of the sub-dominant FMP-associated species Lactococcus raffinolactis, which further corresponded to shifts in the urine metabolome. Overall, our results indicated that daily consumption of a single portion of kefir alone resulted in detectable changes to the gut microbiota and metabolome of consumers.
Release of cognitive and multimodal MRI data including real-world tasks and hippocampal subfield segmentations
Authors: Clark Ian A. , Maguire Eleanor A.
Published: August 2023

We share data from N = 217 healthy adults (mean age 29 years, range 20–41; 109 females, 108 males) who underwent extensive cognitive assessment and neuroimaging to examine the neural basis of individual differences, with a particular focus on a brain structure called the hippocampus. Cognitive data were collected using a wide array of questionnaires, naturalistic tests that examined imagination, autobiographical memory recall and spatial navigation, traditional laboratory-based tests such as recalling word pairs, and comprehensive characterisation of the strategies used to perform the cognitive tests. 3 Tesla MRI data were also acquired and include multi-parameter mapping to examine tissue microstructure, diffusion-weighted MRI, T2-weighted high-resolution partial volume structural MRI scans (with the masks of hippocampal subfields manually segmented from these scans), whole brain resting state functional MRI scans and partial volume high resolution resting state functional MRI scans. This rich dataset will be of value to cognitive and clinical neuroscientists researching individual differences, real-world cognition, brain-behaviour associations, hippocampal subfields and more. All data are freely available on Dryad.
Chromosome-level genome assembly of the caenogastropod snail Rapana venosa
Authors: Song Hao , Li Zhuoqing , Yang Meijie , Shi Pu , Yu Zhenglin , Hu Zhi , Zhou Cong , Hu Pengpeng , Zhang Tao
Published: August 2023

The carnivorous gastropod Rapana venosa (Valenciennes, 1846) is one of the most notorious ecological invaders worldwide. Here, we present the first high-quality chromosome-scale reference R. venosa genome obtained via PacBio sequencing, Illumina paired-end sequencing, and high-throughput chromosome conformation capture scaffolding. The assembled genome has a size of 2.30 Gb, with a scaffold N50 length of 64.63 Mb, and is anchored to 35 chromosomes. It contains 29,649 protein-coding genes, 77.22% of which were functionally annotated. Given its high heterozygosity (1.41%) and large proportion of repeat sequences (57.72%), it is one of the most complex genome assemblies. This chromosome-level genome assembly of R. venosa is an important resource for understanding molluscan evolutionary adaption and provides a genetic basis for its biological invasion control.
L-lysine moderates thermal aggregation of coconut proteins induced by thermal treatment
Authors: Wang Liqiang , Zhang Youbang , Li Run , Xiang Dong
Published: August 2023

This work attempts to investigate the inhibitory effect of L-lysine (Lys) on the thermal aggregation of coconut protein (CP). The results showed that under neutral conditions (pH = 7), temperature reduced the solubility and enhanced the thermally induced gel formation of CP. In addition, Lys reduced the fluorescence properties, particle size and increased the turbidity of CP, which had an inhibitory effect on heat induced gels. The results indicate that Lys plays an important role in inhibiting protein thermal aggregation by interacting with CP to create steric hindrance and increase protein electrostatic repulsion.
The effect of resveratrol, curcumin and quercetin combination on immuno-suppression of tumor microenvironment for breast tumor-bearing mice
Authors: Li Chenchen , Xu Yajun , Zhang Junfeng , Zhang Yuxi , He Wen , Ju Jiale , Wu Yinghua , Wang Yanli
Published: August 2023

Resveratrol, curcumin, and quercetin are the secondary metabolites from medicinal food homology plants, that have been proven their potency in cancer treatment. However, the antitumor effect of a single component is weak. So, herein, we designed an antitumor compound named RCQ composed of resveratrol, curcumin, and quercetin. This study examined the effect on tumorigenesis and development of 4T1 breast cancer-bearing mice following administering RCQ by intragastric administration. RCQ increased the recruitment of T cells and reduced the accumulation of neutrophils and macrophages in the tumor microenvironment. Meanwhile, RCQ suppressed the development of tumor-infiltrating lymphocytes into immunosuppressive cell subpopulations, including CD4+ T cells to T helper Type 2 type (Th2), tumor-associated neutrophils (TANs) to the N2 TANs, and tumor-associated macrophages (TAMs) cells to M2 TAMs. RCQ reversed the predominance of immunosuppressive infiltrating cells in the tumor microenvironment and tipped the immune balance toward an immune activation state. In vitro the study showed that RCQ significantly increased reactive oxygen species (ROS), reduce mitochondrial membrane potentials in cancer cells, and modulate pro-apoptotic Bcl-2 family members. In conclusion, RCQ can promote the ROS apoptosis mechanism of tumor cells and alleviate immunosuppression of the tumor microenvironment to enhance the anti-tumor effect.
Altered structural hippocampal intra-networks in a general elderly Japanese population with mild cognitive impairment
Authors: Kasai Sera , Watanabe Keita , Umemura Yoshihito , Ishimoto Yuka , Sasaki Miho , Nagaya Haruka , Tatsuo Soichiro , Mikami Tatsuya , Tamada Yoshinori , Ide Satoru , Tomiyama Masahiko , Matsuzaka Masashi , Kakeda Shingo
Published: August 2023

Although altered networks inside the hippocampus (hippocampal intra-networks) have been observed in dementia, the evaluation of hippocampal intra-networks using magnetic resonance imaging (MRI) is challenging. We employed conventional structural imaging and incident component analysis (ICA) to investigate the structural covariance of the hippocampal intra-networks. We aimed to assess altered hippocampal intra-networks in patients with mild cognitive impairment (MCI). A cross-sectional study of 2122 participants with 3T MRI (median age 69 years, 60.9% female) were divided into 218 patients with MCI and 1904 cognitively normal older adults (CNOA). By employing 3D T1-weighted imaging, voxels within the hippocampus were entered into the ICA analysis to extract the structural covariance intra-networks within the hippocampus. The ICA extracted 16 intra-networks from the hippocampal structural images, which were divided into two bilateral networks and 14 ipsilateral networks. Of the 16 intra-networks, two (one bilateral network and one ipsilateral networks) were significant predictors of MCI from the CNOA after adjusting for age, sex, education, disease history, and hippocampal volume/total intracranial volume ratio. In conclusion, we found that the relationship between hippocampal intra-networks and MCI was independent from the hippocampal volume. Our results suggest that altered hippocampal intra-networks may reflect a different pathology in MCI from that of brain atrophy.
Specific patterns of neural activity in the hippocampus after massed or distributed spatial training
Authors: Centofante Eleonora , Fralleoni Luca , Lupascu Carmen A. , Migliore Michele , Rinaldi Arianna , Mele Andrea
Published: August 2023

Training with long inter-session intervals, termed distributed training, has long been known to be superior to training with short intervals, termed massed training. In the present study we compared c-Fos expression after massed and distributed training protocols in the Morris water maze to outline possible differences in the learning-induced pattern of neural activation in the dorsal CA1 in the two training conditions. The results demonstrate that training and time lags between learning opportunities had an impact on the pattern of neuronal activity in the dorsal CA1. Mice trained with the distributed protocol showed sustained neuronal activity in the postero-distal component of the dorsal CA1. In parallel, in trained mice we found more active cells that tended to constitute spatially restricted clusters, whose degree increased with the increase in the time lags between learning trials. Moreover, activated cell assemblies demonstrated increased stability in their spatial organization after distributed as compared to massed training or control condition. Finally, using a machine learning algorithm we found that differences in the number of c-Fos positive cells and their location in the dorsal CA1 could be predictive of the training protocol used. These results suggest that the topographic organization and the spatial location of learning activated cell assemblies might be critical to promote the increased stability of the memory trace induced by distributed training.
Assessing the effectiveness of camrelizumab plus apatinib versus sorafenib for the treatment of primary liver cancer: a single-center retrospective study
Authors: Chen Dongbo , Wang Yichun , Chen Xiangxun , Kang Mei , Zhu Liyang
Published: August 2023

Although the effectiveness of camrelizumab plus apatinib has been confirmed in a phase II clinical study, the efficacy of camrelizumab plus apatinib versus sorafenib for primary liver cancer (PLC) remains unverified. We retrospectively collected the data of 143 patients with PLC who received camrelizumab plus apatinib or sorafenib as the first-line treatment at The First Affiliated Hospital of Anhui Medical University from April 2018 to November 2021. Of these, 71 patients received an intravenous injection of camrelizumab 200 mg (body weight ≥ 50 kg) or 3 mg/kg (body weight < 50 kg) followed by an oral dosage of apatinib 250 mg/day every 3 weeks and 72 patients received sorafenib 400 mg orally, twice a day in 28-day cycles. The primary outcomes were overall survival and progression-free survival. The secondary outcomes were objective response rate, disease control rate, and safety. The median median progression-free survival and median overall survival with camrelizumab plus apatinib and sorafenib were 6.0 (95% confidence interval (CI) 4.2–7.8) and 3.0 months (95% CI 2.3–3.7) and 19.0 (95% CI 16.4–21.6) and 12.0 months (95% CI 8.9–15.1), respectively (death hazard ratio: 0.61, P = 0.023). Grade 3/4 treatment-related adverse events were noted in 50 (70.4%) patients in the camrelizumab plus apatinib group and 19 (26.4%) patients in the sorafenib group. Two treatment-related deaths were recorded. Clinically significant improvements were observed in overall survival and progression-free survival with camrelizumab plus apatinib versus sorafenib. Although the side effects of camrelizumab plus apatinib are relatively high, they can be controlled.
Development and validation of a sleep questionnaire, SNoRE 3.0, to evaluate sleep in companion dogs
Authors: Mondino A. , Ludwig C. , Menchaca C. , Russell K. , Simon K. E. , Griffith E. , Kis A. , Lascelles B. D. X. , Gruen M. E. , Olby N. J.
Published: August 2023

Disturbances in the sleep–wake cycle are a debilitating, yet rather common condition not only in humans, but also in family dogs. While there is an emerging need for easy-to-use tools to document sleep alterations (in order to ultimately treat and/or prevent them), the veterinary tools which yield objective data (e.g. polysomnography, activity monitors) are both labor intensive and expensive. In this study, we developed a modified version of a previously used sleep questionnaire (SNoRE) and determined criterion validity in companion dogs against polysomnography and physical activity monitors (PAMs). Since a negative correlation between sleep time and cognitive performance in senior dogs has been demonstrated, we evaluated the correlation between the SNoRE scores and the Canine Dementia Scale (CADES, which includes a factor concerning sleep). There was a significant correlation between SNoRE 3.0 questionnaire scores and polysomnography data (latency to NREM sleep, ρ = 0.507, p < 0.001) as well as PAMs’ data (activity between 1:00 and 3:00 AM, p < 0.05). There was a moderate positive correlation between the SNoRE 3.0 scores and the CADES scores (ρ = 0.625, p < 0.001). Additionally, the questionnaire structure was validated by a confirmatory factor analysis, and it also showed an adequate test–retest reliability. In conclusion the present paper describes a valid and reliable questionnaire tool, that can be used as a cost-effective way to monitor dog sleep in clinical settings.
A comparison of the infant gut microbiome before versus after the start of the covid-19 pandemic
Authors: Querdasi Francesca R. , Vogel Sarah C. , Thomason Moriah E. , Callaghan Bridget L. , Brito Natalie H.
Published: August 2023

The COVID-19 pandemic and resulting public health directives led to many changes in families’ social and material environments. Prior research suggests that these changes are likely to impact composition of the gut microbiome, particularly during early childhood when the gut microbiome is developing most rapidly. Importantly, disruption to the gut microbiome during this sensitive period can have potentially long-lasting impacts on health and development. In the current study, we compare gut microbiome composition among a socioeconomically and racially diverse group of 12-month old infants living in New York City who provided stool samples before the pandemic (N = 34) to a group who provided samples during the first 9-months of the pandemic (March–December 2020; N = 20). We found that infants sampled during the pandemic had lower alpha diversity of the microbiome, lower abundance of Pasteurellaceae and Haemophilus, and significantly different beta diversity based on unweighted Unifrac distance than infants sampled before the pandemic. Exploratory analyses suggest that gut microbiome changes due to the pandemic occurred relatively quickly after the start of the pandemic and were sustained. Our results provide evidence that pandemic-related environmental disruptions had an impact on community-level taxonomic diversity of the developing gut microbiome, as well as abundance of specific members of the gut bacterial community.