bluuebunny/crossref_metadata_2025 huggingface dataset:
Semiconducting nonperovskite ferroelectric oxynitride designed ab initio
Authors: Yu Qisheng , Huang Jiawei , Ke Changming , Qian Zhuang , Ma Liyang , Liu Shi
Published: April 2023

The recent discovery of HfO2-based and nitride-based ferroelectrics that are compatible to the semiconductor manufacturing process has revitalized the field of ferroelectric-based nanoelectronics. Guided by a simple design principle of charge compensation and density functional theory calculations, we discover that HfO2-like mixed-anion materials, TaON and NbON, can crystallize in the polar Pca 2 1 phase with a strong thermodynamic driving force to adopt anion ordering spontaneously. Both oxynitrides possess large remnant polarization, low switching barriers, and unconventional negative piezoelectric effect, making them promising piezoelectrics and ferroelectrics. Distinct from HfO2 that has a wide bandgap, both TaON and NbON can absorb visible light and have high charge carrier mobilities, suitable for ferroelectric photovoltaic and photocatalytic applications. This class of multifunctional nonperovskite oxynitride containing economical and environmentally benign elements offers a platform to design and optimize high-performing ferroelectric semiconductors for integrated systems.
Pb, Bi, and rare earth free X6R barium titanate–sodium niobate ceramics for high voltage capacitor applications
Authors: Fan Yongbo , Wang Xinzhen , Li Hongtian , Feteira Antonio , Wang Dawei , Wang Ge , Sinclair Derek C. , Reaney Ian M.
Published: April 2023

0.9Ba(Ti1−xMgx)O3−x-0.1NaNbO3 (BTNN-100xMg) solid solutions are investigated with a view to developing Bi, Pb, and rare earth free, high voltage multilayer ceramic capacitors. Mg doping on the B-site significantly reduced the electronic conductivity and resulted in ceramics that could withstand a pulsed unipolar field of >300 kV/cm (Emax) to give a recoverable energy density of 3.4 J/cm3 at 82.6% efficiency for x = 0.01. The high Emax is accompanied by a high dielectric permittivity (ε′ ∼ 1700 at room temperature) with temperature-stable dielectric permittivity of Δε/ε298K ≤ ±15% and loss tangent tan δ < 0.02 from 116 to 378 K, corresponding to an X6R designation in the Electronic Industry Alliance codes.
Modeling density effects on electronic configurations in warm dense plasmas
Authors: Faussurier Gérald
Published: April 2023

We present a method to calculate the shift of the K edge in warm dense aluminum. We use the average-atom model and show how to build the energy of an electronic configuration with integer subshell populations and by taking into account the interaction of the bound electrons with the free electrons. We successfully compare our calculation of the spectral opacity with the Henke table for aluminum at solid density and 300 K. We found a redshift of the K edge along the principal Hugoniot consistent with experimental data. We also compute the 2s and 2p edges. We obtain L edge redshifts similar to the K edge redshift.
Transport properties in liquids from first-principles: The case of liquid water and liquid argon
Authors: Silvestrelli Pier Luigi
Published: April 2023

Shear and bulk viscosities of liquid water and argon are evaluated from first-principles in the density functional theory (DFT) framework, by performing molecular dynamics simulations in the NVE ensemble and using the Kubo–Greenwood equilibrium approach. The standard DFT functional is corrected in such a way to allow for a reasonable description of van der Waals effects. For liquid argon, the thermal conductivity has been also calculated. Concerning liquid water, to our knowledge, this is the first estimate of the bulk viscosity and of the shear-viscosity/bulk-viscosity ratio from first-principles. By analyzing our results, we can conclude that our first-principles simulations, performed at a nominal average temperature of 366 to guarantee that the systems are liquid-like, actually describe the basic dynamical properties of liquid water at about 330 K. In comparison with liquid water, the normal, monatomic liquid Ar is characterized by a much smaller bulk-viscosity/shear-viscosity ratio (close to unity) and this feature is well reproduced by our first-principles approach, which predicts a value of the ratio in better agreement with experimental reference data than that obtained using the empirical Lennard-Jones potential. The computed thermal conductivity of liquid argon is also in good agreement with the experimental value.
Marangoni destabilization of bidimensional-confined gas–liquid co-flowing streams in rectangular microfluidic channels
Authors: Clerget Mattéo , Klimenko Alexandra , Bourrel Maurice , Lequeux François , Panizza Pascal
Published: April 2023

In microchannels, the stability of a fluid jet injected into another immiscible fluid strongly depends on its degree of geometric confinement. When the width of the jet, w, is larger than the channel height, H, the surface tension driven Rayleigh–Plateau instability is suppressed so that the 2D (bidimensional)-confined jet is absolutely stable and never collapses into bubbles (or drops) in contrast to what occurs when w ≤ H [Dollet et al., “Role of the channel geometry on the bubble pinch-off in flow-focusing,” Phys. Rev. Lett. 100(3), 034504 (2008); Guillot et al., “Stability of a jet in confined pressure-driven biphasic flows at low Reynolds number in various geometries,” Phys. Rev. E 78(1), 016307 (2008)]. We here demonstrate both experimentally and theoretically that this picture is, indeed, no longer valid when Marangoni effects are considered. We experimentally show that the addition of small length alcohol molecules into the liquid phase destabilizes a 2D-confined gas–water microfluidic stream ( w > H), leading to the generation of steady non-linear waves and further to the production of bubbles. Using a simple hydrodynamic model, we show through a linear analysis that the destabilization of the gas stream may result from a Marangoni instability due to the fast adsorption of the alcohol molecules, which occurs on a timescale comparable to that of the microfluidic flow.
Spontaneous spin and valley polarizations in a two-dimensional Cr2S3 monolayer
Authors: Li Yan , Wu Yanzhao , Deng Li , Yin Xiang , Han Xiaoli , Tian Fubo , Zhang Xianmin
Published: April 2023

Valleytronics has attracted much attention due to its potential applications in information progress and data storage. In this paper, monolayer Cr2S3 is proven to be a ferromagnetic (FM) semiconductor by using first-principles calculations. Moreover, monolayer Cr2S3 exhibits a perpendicular magnetic anisotropy energy of 30 μeV/f.u. Surprisingly, monolayer Cr2S3 presents spontaneous valley polarization, which means that it will be nonvolatile for data storage. Notably, monolayer Cr2S3 changes to an antiferromagnetic (AFM) state from the original FM state under biaxial tensile strain, and its easy axis will be reorientated from out-of-plane to in-plane when the compressive strain is larger than −2%. Importantly, for AFM monolayer Cr2S3, the valley polarization reversion can be realized by an external electric field along the z direction. In brief, valley polarization has been achieved in both FM and AFM monolayer Cr2S3, which is very rare in other valleytronics research. The present research provides a tantalizing candidate for realizing and manipulating valley and spin physics.
Internal explosions and their effects on humans
Authors: Kokkinakis Ioannis W. , Drikakis Dimitris
Published: April 2023

This paper concerns indoor explosions and the impact of blasts on humans. The standard approach from the engineering and medical communities is that blast overpressure is the criterion that determines trauma and injury. However, this study shows that the wind force generated behind the blast can affect humans more significantly, even for relatively low blast overpressures. Although the present findings also apply to external explosions, we chose the indoor case as this is a more complex problem. We present high-order simulations for an explosion equivalent to 2.5 lbs of trinitrotoluene in a simplified indoor environment comprising three rooms and a corridor. The explosion magnitude could correspond to a malicious act, such as someone carrying a rucksack with the above explosive. The study reveals that the force generated can be up to 60 times the human's weight, even in the spaces adjacent to the room where the explosion occurred. The blast effects will be fatal for humans in the room where the explosion occurs. The impact on human organs, such as the lungs, brain, and gastrointestinal system, will vary in the adjacent spaces. The likelihood of primary injury increases from the repeated shockwaves due to their continuous reflections of the walls, impacting the lungs and gastrointestinal tract significantly and causing eardrums to burst and brain hemorrhage. Secondary blast injuries will occur due to the debris and high airspeeds behind the blast. Corridors and locations facing the doors are particularly dangerous. The simulations show a common asymptotic decay behavior of the wind force and blast overpressure across rooms at later times. The study concludes that forces resulting from the high airspeeds that develop are likely to cause greater injury than the blast overpressure itself.
Attenuation of Tollmien–Schlichting waves using resonating surface-embedded phononic crystals
Authors: Michelis T. , Putranto A. B. , Kotsonis M.
Published: April 2023

A novel method for control of convective boundary layer instabilities using metamaterial concepts is investigated. Attenuation of Tollmien–Schlichting (TS) waves with surface-embedded one-dimensional phononic crystals (PCs) is theoretically and numerically modeled, capitalizing on the inherent frequency band stop of PCs. The PC is tuned to the targeted TS wave characteristics through the use of analytical models derived from transfer matrix and interface response theories, verified using a finite elements analysis. The interaction between TS waves and a single PC is investigated using coupled two-dimensional fluid structure interaction simulations in the frequency domain. It is shown that TS waves are either amplified or attenuated depending on whether the PC free-face surface displacement and unsteady perturbation pressure at the wall are in-phase or out-of-phase, respectively. The perturbation pressure acts solely as the driver for the mechanical oscillation of the PC. The emerging hydrodynamic coupling between TS waves and the PC is found to be governed by a combination of the Orr mechanism and wall-normal velocity linear superposition near the wall. Finally, a metasurface comprised of an array of streamwise-distributed PCs is evaluated, resulting in an amplitude growth delay of 11.3% of the TS wavelength along the metasurface extent.
Time spent feeding as an early indicator of metritis in postpartum dairy cows: systematic review and meta-analysis
Authors: Cocco R. , Canozzi M. E. A. , Vieira A. C. , Fischer V.
Published: April 2023

Context Feeding behaviour is an important tool for the early detection of diseases in dairy cows. Aims The aim of this study was to evaluate whether the variation in time spent feeding in the prepartum and postpartum periods may be used to detect the occurrence of metritis and subclinical ketosis (SCK) before the onset of the clinical symptoms at the postpartum. Methods The research was conducted in four electronic databases, including Scopus, Science Direct, Pubmed, and Web of Science. The inclusion criteria for citations were original research, evaluation of daily time spent feeding in dairy cows, and use of this indicator for early identification of metritis and/or SCK in dairy cows in the prepartum and postpartum periods. A random-effect meta-analysis (MA) was conducted for metritis with the time spent feeding means of control (healthy) and treated (sick) groups measured in the prepartum and postpartum periods. The analysis was conducted with the values of daily time spent feeding before and after calving in both groups. Key results In total, 26 trials from six papers, involving 1037 dairy cows, were included in the statistical analysis. No data were obtained for SCK to conduct a MA, while for metritis, 16 trials from six papers (prepartum) and 10 trials from three papers (postpartum) were considered. The heterogeneity between studies on metritis was moderate (I2 = 57.5%) in the prepartum period and low (I2 = 10.0%) in the postpartum period. The mean difference feeding time for healthy and unhealthy animals was greater during postpartum (21.14 min/day, P < 0.001) than during prepartum (16.36 min/day, P < 0.001). Meta-regression analysis showed that number of daily milkings, sample size, and the place of running trial significantly influenced the time spent feeding by cows. Conclusion On the basis of available and suitable scientific literature, time spent feeding is reduced at the prepartum and postpartum periods in dairy cows further affected by metritis. Implications This study evidenced that feeding time might be incorporated into health-monitoring protocols for early detection of metritis in dairy cows.
A copy number variant near KITLG is associated with the roan pattern in alpacas
Authors: Shah Ishani , Gray Naomi , Groth David , Brooks Samantha , Munyard Kylie
Published: April 2023

Context The alpaca roan pattern is characterised by white and coloured fibre interspersed together, with a distinctive lighter body and darker extremities, and commonly is believed to be inherited in an autosomal dominant manner. It is of interest to the alpaca fibre industry as it causes ‘contamination’ of coloured fibre with white fibres, but cannot be detected in white or light fawn animals. Other livestock species, such as horses, cattle, goats, and pigs, exhibit comparable phenotypes, which are associated with candidate variant(s) in either KIT or KITLG. Aims To identify a region or regions of the genome that is/are causative of the roan pattern in alpacas. Methods We conducted a genome-wide association study (GWAS) by using 13 roan and 14 non-roan alpacas sampled from the USA, Australia, and New Zealand. Regions of genome-wide significance were examined for variants that correlated with the roan phenotype. Key results A novel candidate single-nucleotype polymorphism (SNP; Super-Scaffold_15:39 742 851T > A), located 272 kb upstream of KITLG, was identified in 1 of 12 regions with genome-wide significant association (P ≤ 5 × 10−8). We identified the candidate SNP-containing region (Super-Scaffold_15:39 742 096–39 887 419) to be a 145 kb copy number variant (CNV) that is likely to be a tandem duplication. All 13 roan alpacas had one or two copies of the roan-associated T allele and all except three non-roans had zero copies. Furthermore, we determined the Mendelian inheritance of copy number haplotypes and their allelic composition in a roan and a non-roan family. Conclusions Our data support the hypothesised autosomal incomplete dominant mode of inheritance of the roan pattern in alpacas and suggests that the effect of the T allele CNV version is likely to be suppressed when in cis with the A allele CNV version. However, additional verification is required to validate the finding and determine the functional effect. Implications Identification of the cause, or a marker for roan pattern will allow alpaca breeders to select for or against the roan pattern, even when the phenotype is hidden, and therefore increase production output and profitability.
The expansion of agriculture has shaped the recent evolutionary history of a specialized squash pollinator
Authors: Pope Nathaniel S. , Singh Avehi , Childers Anna K. , Kapheim Karen M. , Evans Jay D. , López-Uribe Margarita M.
Published: April 2023

The expansion of agriculture is responsible for the mass conversion of biologically diverse natural environments into managed agroecosystems dominated by a handful of genetically homogeneous crop species. Agricultural ecosystems typically have very different abiotic and ecological conditions from those they replaced and create potential niches for those species that are able to exploit the abundant resources offered by crop plants. While there are well-studied examples of crop pests that have adapted into novel agricultural niches, the impact of agricultural intensification on the evolution of crop mutualists such as pollinators is poorly understood. We combined genealogical inference from genomic data with archaeological records to demonstrate that the Holocene demographic history of a wild specialist pollinator of
Cucurbita
(pumpkins, squashes, and gourds) has been profoundly impacted by the history of agricultural expansion in North America. Populations of the squash bee
Eucera pruinosa
experienced rapid growth in areas where agriculture intensified within the past 1,000 y, suggesting that the cultivation of
Cucurbita
in North America has increased the amount of floral resources available to these bees. In addition, we found that roughly 20% of this bee species’ genome shows signatures of recent selective sweeps. These signatures are overwhelmingly concentrated in populations from eastern North America where squash bees were historically able to colonize novel environments due to human cultivation of
Cucurbita pepo
and now exclusively inhabit agricultural niches. These results suggest that the widespread cultivation of crops can prompt adaptation in wild pollinators through the distinct ecological conditions imposed by agricultural environments.
Cellular segregation in cocultures is driven by differential adhesion and contractility on distinct timescales
Authors: Skamrahl Mark , Schünemann Justus , Mukenhirn Markus , Pang Hongtao , Gottwald Jannis , Jipp Marcel , Ferle Maximilian , Rübeling Angela , Oswald Tabea A. , Honigmann Alf , Janshoff Andreas
Published: April 2023

Cellular sorting and pattern formation are crucial for many biological processes such as development, tissue regeneration, and cancer progression. Prominent physical driving forces for cellular sorting are differential adhesion and contractility. Here, we studied the segregation of epithelial cocultures containing highly contractile, ZO1/2-depleted MDCKII cells (dKD) and their wild-type (WT) counterparts using multiple quantitative, high-throughput methods to monitor their dynamical and mechanical properties. We observe a time-dependent segregation process governed mainly by differential contractility on short (<5 h) and differential adhesion on long (>5 h) timescales. The overly contractile dKD cells exert strong lateral forces on their WT neighbors, thereby apically depleting their surface area. Concomitantly, the tight junction–depleted, contractile cells exhibit weaker cell–cell adhesion and lower traction force. Drug-induced contractility reduction and partial calcium depletion delay the initial segregation but cease to change the final demixed state, rendering differential adhesion the dominant segregation force at longer timescales. This well-controlled model system shows how cell sorting is accomplished through a complex interplay between differential adhesion and contractility and can be explained largely by generic physical driving forces.
Predicting climate change impacts on poikilotherms using physiologically guided species abundance models
Authors: Wagner Tyler , Schliep Erin M. , North Joshua S. , Kundel Holly , Custer Christopher A. , Ruzich Jenna K. , Hansen Gretchen J. A.
Published: April 2023

Poikilothermic animals comprise most species on Earth and are especially sensitive to changes in environmental temperatures. Species conservation in a changing climate relies upon predictions of species responses to future conditions, yet predicting species responses to climate change when temperatures exceed the bounds of observed data is fraught with challenges. We present a physiologically guided abundance (PGA) model that combines observations of species abundance and environmental conditions with laboratory-derived data on the physiological response of poikilotherms to temperature to predict species geographical distributions and abundance in response to climate change. The model incorporates uncertainty in laboratory-derived thermal response curves and provides estimates of thermal habitat suitability and extinction probability based on site-specific conditions. We show that temperature-driven changes in distributions, local extinction, and abundance of cold, cool, and warm-adapted species vary substantially when physiological information is incorporated. Notably, cold-adapted species were predicted by the PGA model to be extirpated in 61% of locations that they currently inhabit, while extirpation was never predicted by a correlative niche model. Failure to account for species-specific physiological constraints could lead to unrealistic predictions under a warming climate, including underestimates of local extirpation for cold-adapted species near the edges of their climate niche space and overoptimistic predictions of warm-adapted species.
E2F regulation of the
Phosphoglycerate kinase
gene is functionally important in
Drosophila
development
Authors: Zappia Maria Paula , Kwon Yong-Jae , Westacott Anton , Liseth Isabel , Lee Hyun Min , Islam Abul B. M. M. K. , Kim Jiyeon , Frolov Maxim V.
Published: April 2023

The canonical role of the transcription factor E2F is to control the expression of cell cycle genes by binding to the E2F sites in their promoters. However, the list of putative E2F target genes is extensive and includes many metabolic genes, yet the significance of E2F in controlling the expression of these genes remains largely unknown. Here, we used the CRISPR/Cas9 technology to introduce point mutations in the E2F sites upstream of five endogenous metabolic genes in
Drosophila melanogaster
. We found that the impact of these mutations on both the recruitment of E2F and the expression of the target genes varied, with the glycolytic gene,
Phosphoglycerate kinase
(
Pgk)
, being mostly affected. The loss of E2F regulation on the
Pgk
gene led to a decrease in glycolytic flux, tricarboxylic acid cycle intermediates levels, adenosine triphosphate (ATP) content, and an abnormal mitochondrial morphology. Remarkably, chromatin accessibility was significantly reduced at multiple genomic regions in

Pgk
ΔE2F

mutants. These regions contained hundreds of genes, including metabolic genes that were downregulated in

Pgk
ΔE2F

mutants. Moreover,

Pgk
ΔE2F

animals had shortened life span and exhibited defects in high-energy consuming organs, such as ovaries and muscles. Collectively, our results illustrate how the pleiotropic effects on metabolism, gene expression, and development in the

Pgk
ΔE2F

animals underscore the importance of E2F regulation on a single E2F target,
Pgk
.
On the origin of appetite: GLWamide in jellyfish represents an ancestral satiety neuropeptide
Authors: Thoma Vladimiros , Sakai Shuhei , Nagata Koki , Ishii Yuu , Maruyama Shinichiro , Abe Ayako , Kondo Shu , Kawata Masakado , Hamada Shun , Deguchi Ryusaku , Tanimoto Hiromu
Published: April 2023

Food intake is regulated by internal state. This function is mediated by hormones and neuropeptides, which are best characterized in popular model species. However, the evolutionary origins of such feeding-regulating neuropeptides are poorly understood. We used the jellyfishCladonemato address this question. Our combined transcriptomic, behavioral, and anatomical approaches identified GLWamide as a feeding-suppressing peptide that selectively inhibits tentacle contraction in this jellyfish. In the fruit flyDrosophila, myoinhibitory peptide (MIP) is a related satiety peptide. Surprisingly, we found that GLWamide and MIP were fully interchangeable in these evolutionarily distant species for feeding suppression. Our results suggest that the satiety signaling systems of diverse animals share an ancient origin.
A cognitive pathway to punishment insensitivity
Authors: Jean-Richard-dit-Bressel Philip , Lee Jessica C. , Liew Shi Xian , Weidemann Gabrielle , Lovibond Peter F. , McNally Gavan P.
Published: April 2023

Individuals differ in their sensitivity to the adverse consequences of their actions, leading some to persist in maladaptive behaviors. Two pathways have been identified for this insensitivity: a motivational pathway based on excessive reward valuation and a behavioral pathway based on autonomous stimulus–response mechanisms. Here, we identify a third, cognitive pathway based on differences in punishment knowledge and use of that knowledge to suppress behavior. We show that distinct phenotypes of punishment sensitivity emerge from differences in what people learn about their actions. Exposed to identical punishment contingencies, some people (sensitive phenotype) form correct causal beliefs that they use to guide their behavior, successfully obtaining rewards and avoiding punishment, whereas others form incorrect but internally coherent causal beliefs that lead them to earn punishment they do not like. Incorrect causal beliefs were not inherently problematic because we show that many individuals benefit from information about why they are being punished, revaluing their actions and changing their behavior to avoid further punishment (unaware phenotype). However, one condition where incorrect causal beliefs were problematic was when punishment is infrequent. Under this condition, more individuals show punishment insensitivity and detrimental patterns of behavior that resist experience and information-driven updating, even when punishment is severe (compulsive phenotype). For these individuals, rare punishment acted as a “trap,” inoculating maladaptive behavioral preferences against cognitive and behavioral updating.
Closed-loop recyclable membranes enabled by covalent adaptable networks for water purification
Authors: Li Bofan , Wang Sheng , Loh Xian Jun , Li Zibiao , Chung Tai-Shung
Published: April 2023

In the state-of-the-art membrane industry, membranes have linear life cycles and are commonly disposed of by landfill or incineration, sacrificing their sustainability. To date, little or no thought is given in the design phase to the end-of-life management of membranes. For the first time, we have innovated high-performance sustainable membranes, which can be closed-loop recycled after long-term usage for water purification. By synergizing membrane technology and dynamic covalent chemistry, covalent adaptable networks (CANs) with thermally reversible Diels–Alder (DA) adducts were synthesized and employed to fabricate integrally skinned asymmetric membranes via the nonsolvent-induced phase separation technique. Due to the stable and reversible features of CAN, the closed-loop recyclable membranes exhibit excellent mechanical properties and thermal and chemical stabilities as well as separation performance, which are comparable to or even higher than the state-of-the-art nonrecyclable membranes. Moreover, the used membranes can be closed-loop recycled with consistent properties and separation performance by depolymerization to remove contaminants, followed by refabrication into new membranes through the dissociation and reformation of DA adducts. This study may fill in the gaps in closed-loop recycling of membranes and inspire the advancement of sustainable membranes for a green membrane industry.
Arabidopsis
HOT3/eIF5B1 constrains rRNA RNAi by facilitating 18S rRNA maturation
Authors: Hang Runlai , Xu Ye , Wang Xufeng , Hu Hao , Flynn Nora , You Chenjiang , Chen Xuemei
Published: April 2023

Ribosome biogenesis is essential for protein synthesis in gene expression. Yeast eIF5B has been shown biochemically to facilitate 18S ribosomal RNA (rRNA) 3′ end maturation during late-stage 40S ribosomal subunit assembly and gate the transition from translation initiation to elongation. But the genome-wide effects of eIF5B have not been studied at the single-nucleotide resolution in any organism, and 18S rRNA 3′ end maturation is poorly understood in plants.
Arabidopsis
HOT3/eIF5B1 was found to promote development and heat stress acclimation by translational regulation, but its molecular function remained unknown. Here, we show that HOT3 is a late-stage ribosome biogenesis factor that facilitates 18S rRNA 3′ end processing and is a translation initiation factor that globally impacts the transition from initiation to elongation. By developing and implementing 18S-ENDseq, we revealed previously unknown events in 18S rRNA 3′ end maturation or metabolism. We quantitatively defined processing hotspots and identified adenylation as the prevalent nontemplated RNA addition at the 3′ ends of pre-18S rRNAs. Aberrant 18S rRNA maturation in
hot3
further activated RNA interference to generate RDR1- and DCL2/4-dependent risiRNAs mainly from a 3′ portion of 18S rRNA. We further showed that risiRNAs in
hot3
were predominantly localized in ribosome-free fractions and were not responsible for the 18S rRNA maturation or translation initiation defects in
hot3
. Our study uncovered the molecular function of HOT3/eIF5B1 in 18S rRNA maturation at the late 40S assembly stage and revealed the regulatory crosstalk among ribosome biogenesis, messenger RNA (mRNA) translation initiation, and siRNA biogenesis in plants.
From evaluative authorities to involved narrators
Authors: Posio Pekka , Heikkilä Riie
Published: April 2023

Is the use of the first-person singular becoming more prevalent in journalistic writing, like often claimed, and what is it used for? In order to tackle these questions, we analysed 11,775 articles published between 1960 and 2010 in the cultural sections ofABCandEl País(Spain),Dagens Nyheter(Sweden),Helsingin Sanomat(Finland),Le Monde(France), andThe Guardian(UK). Our analysis focuses on the variation and change in the frequency and functions of first-person singular pronoun and verb forms over time and between different newspapers. We provide a logistic regression analysis of the whole dataset, as well as a qualitative analysis of the 1,077 articles containing at least one first-person singular. The analyses reveal a considerable amount of variation in first-person singular usage between each newspaper. The findings, however, converge to reveal that the frequency of first-persons singulars increases over time while its narrative uses become predominant at the expense of the evaluative and epistemic ones.
GxcM-Fbp17/RacC-WASP signaling regulates polarized cortex assembly in migrating cells via Arp2/3
Authors: Li Dong , Yang Yihong , Lv Chenglin , Wang Yingjie , Chao Xiaoting , Huang Jiafeng , Singh Shashi P. , Yuan Ye , Zhang Chengyu , Lou Jizhong , Gao Pu , Huang Shanjin , Li Bo , Cai Huaqing
Published: April 2023

The actin-rich cortex plays a fundamental role in many cellular processes. Its architecture and molecular composition vary across cell types and physiological states. The full complement of actin assembly factors driving cortex formation and how their activities are spatiotemporally regulated remain to be fully elucidated. Using Dictyostelium as a model for polarized and rapidly migrating cells, we show that GxcM, a RhoGEF localized specifically in the rear of migrating cells, functions together with F-BAR protein Fbp17, a small GTPase RacC, and the actin nucleation-promoting factor WASP to coordinately promote Arp2/3 complex-mediated cortical actin assembly. Overactivation of this signaling cascade leads to excessive actin polymerization in the rear cortex, whereas its disruption causes defects in cortical integrity and function. Therefore, apart from its well-defined role in the formation of the protrusions at the cell front, the Arp2/3 complex-based actin carries out a previously unappreciated function in building the rear cortical subcompartment in rapidly migrating cells.
ClC-7 drives intraphagosomal chloride accumulation to support hydrolase activity and phagosome resolution
Authors: Wu Jing Ze , Zeziulia Mariia , Kwon Whijin , Jentsch Thomas J. , Grinstein Sergio , Freeman Spencer A.
Published: April 2023

Degradative organelles contain enzymes that function optimally at the acidic pH generated by the V-ATPase. The resulting transmembrane H+ gradient also energizes the secondary transport of several solutes, including Cl−. We report that Cl− influx, driven by the 2Cl−/H+ exchanger ClC-7, is necessary for the resolution of phagolysosomes formed by macrophages. Cl− transported via ClC-7 had been proposed to provide the counterions required for electrogenic H+ pumping. However, we found that deletion of ClC-7 had a negligible effect on phagosomal acidification. Instead, luminal Cl− was found to be required for activation of a wide range of phagosomal hydrolases including proteases, nucleases, and glycosidases. These findings argue that the primary role of ClC-7 is the accumulation of (phago)lysosomal Cl− and that the V-ATPases not only optimize the activity of degradative hydrolases by lowering the pH but, importantly, also play an indirect role in their activation by providing the driving force for accumulation of luminal Cl− that stimulates hydrolase activity allosterically.
Symmetry breaking and competition effect in phase transitions
Authors: Yang Shuang-Liang , Luo Wei , Badshah Fazal , Zhou Yuan , Fu Yan-Hua , Tong Rui , Wu Cheng-Rui , Hu Yong-Jin , Chen Jie , Zeng Wei-You
Published: April 2023

This study is started from a photon-magnon model with a competition effect of the level attraction and repulsion, its Hermiticity is mainly decided by a phase-dependent and asymmetric coupling factor, namely φ = 0 for Hermitian and

ϕ
=
π

for non-Hermitian. Then an extensional study predicts the quantum critical behaviors using an Hermitian and even no-Hermitian photon-spins model with an additional second-order drive. The numerical results firstly indicate that this coupling phase φ can function the protective effect on quantum phase transitions (QPTs), and the new tricritical points can not only be modulated by this nonlinear drive, but also be influenced by the dissipation and the collective decoherence. Secondly, this competition effect can also induce a reversal of the value of order parameters between the positive and negative. This study can also bring more important results of QPTs toward the issue of symmetry breaking and non-Hermiticity.
Nanoscale imaging of quantum dot dimers using time-resolved super-resolution microscopy combined with scanning electron microscopy
Authors: Dunlap Megan K , Ryan Duncan P , Goodwin Peter M , Sheehan Chris J , Werner James H , Majumder Somak , Hollingsworth Jennifer A , Gelfand Martin P , Van Orden Alan
Published: April 2023

Time-resolved super-resolution microscopy was used in conjunction with scanning electron microscopy to image individual colloidal CdSe/CdS semiconductor quantum dots (QD) and QD dimers. The photoluminescence (PL) lifetimes, intensities, and structural parameters were acquired with nanometer scale spatial resolution and sub-nanosecond time resolution. The combination of these two techniques was more powerful than either alone, enabling us to resolve the PL properties of individual QDs within QD dimers as they blinked on and off, measure interparticle distances, and identify QDs that may be participating in energy transfer. The localization precision of our optical imaging technique was ∼3 nm, low enough that the emission from individual QDs within the dimers could be spatially resolved. While the majority of QDs within dimers acted as independent emitters, at least one pair of QDs in our study exhibited lifetime and intensity behaviors consistent with resonance energy transfer from a shorter lifetime and lower intensity donor QD to a longer lifetime and higher intensity acceptor QD. For this case, we demonstrate how the combined super-resolution optical imaging and scanning electron microscopy data can be used to characterize the energy transfer rate.
Vertical strain engineering of Van der Waals heterostructures
Authors: Bian Jinbo , Xu Zhiping
Published: April 2023

Van der Waals materials and their interfaces play critical roles in defining electrical contacts for nanoelectronics and developing vehicles for mechanoelectrical energy conversion. In this work, we propose a vertical strain engineering approach by enforcing pressure across the heterostructures. First-principles calculations show that the in-plane band structures of 2D materials such as graphene, h-BN, and MoS2 as well as the electronic coupling at their contacts can be significantly modified. For the graphene/h-BN contact, a band gap in graphene is opened, while at the graphene/MoS2 interface, the band gap of MoS2 and the Schottky barrier height at contact diminish. Changes and transitions in the nature of contacts are attributed to localized orbital coupling and analyzed through the redistribution of charge densities, the crystal orbital Hamilton population, and electron localization, which yield consistent measures. These findings offer key insights into the understanding of interfacial interaction between 2D materials as well as the efficiency of electronic transport and energy conversion processes.
Single proton LET characterization with the Timepix detector and artificial intelligence for advanced proton therapy treatment planning
Authors: Stasica Paulina , Nguyen Hanh , Granja Carlos , Kopeć Renata , Marek Lukas , Oancea Cristina , Raczyński Łukasz , Rucinski Antoni , Rydygier Marzena , Schubert Keith , Schulte Reinhard , Gajewski Jan
Published: April 2023

Objective. Protons have advantageous dose distributions and are increasingly used in cancer therapy. At the depth of the Bragg peak range, protons produce a mixed radiation field consisting of low- and high-linear energy transfer (LET) components, the latter of which is characterized by an increased ionization density on the microscopic scale associated with increased biological effectiveness. Prediction of the yield and LET of primary and secondary charged particles at a certain depth in the patient is performed by Monte Carlo simulations but is difficult to verify experimentally. Approach. Here, the results of measurements performed with Timepix detector in the mixed radiation field produced by a therapeutic proton beam in water are presented and compared to Monte Carlo simulations. The unique capability of the detector to perform high-resolution single particle tracking and identification enhanced by artificial intelligence allowed to resolve the particle type and measure the deposited energy of each particle comprising the mixed radiation field. Based on the collected data, biologically important physics parameters, the LET of single protons and dose-averaged LET, were computed. Main results. An accuracy over 95% was achieved for proton recognition with a developed neural network model. For recognized protons, the measured LET spectra generally agree with the results of Monte Carlo simulations. The mean difference between dose-averaged LET values obtained from measurements and simulations is 17%. We observed a broad spectrum of LET values ranging from a fraction of keV μm−1 to about 10 keV μm−1 for most of the measurements performed in the mixed radiation fields. Significance. It has been demonstrated that the introduced measurement method provides experimental data for validation of LETD or LET spectra in any treatment planning system. The simplicity and accessibility of the presented methodology make it easy to be translated into a clinical routine in any proton therapy facility.
Data-driven ion-independent relative biological effectiveness modeling using the beam quality Q
Authors: Tian Liheng , Lühr Armin
Published: April 2023

Beam quality Q = Z2/E (Z = ion charge, E = energy), an alternative to the conventionally used linear energy transfer (LET), enables ion-independent modeling of the relative biological effectiveness (RBE) of ions. Therefore, the Q concept, i.e. different ions with similar Q have similar RBE values, could help to transfer clinical RBE knowledge from better-studied ion types (e.g. carbon) to other ions. However, the validity of the Q concept has so far only been demonstrated for low LET values. In this work, the Q concept was explored in a broad LET range, including the so-called overkilling region. The particle irradiation data ensemble (PIDE) was used as experimental in vitro dataset. Data-driven models, i.e. neural network (NN) models with low complexity, were built to predict RBE values for H, He, C and Ne ions at different in vitro endpoints taking different combinations of clinically available candidate inputs: LET, Q and linear-quadratic photon parameter α
x/β
x. Models were compared in terms of prediction power and ion dependence. The optimal model was compared to published model data using the local effect model (LEM IV). The NN models performed best for the prediction of RBE at reference photon doses between 2 and 4 Gy or RBE near 10% cell survival, using only α
x/β
x and Q instead of LET as input. The Q model was not significantly ion dependent (p > 0.5) and its prediction power was comparable to that of LEM IV. In conclusion, the validity of the Q concept was demonstrated in a clinically relevant LET range including overkilling. A data-driven Q model was proposed and observed to have an RBE prediction power comparable to a mechanistic model regardless of particle type. The Q concept provides the possibility of reducing RBE uncertainty in treatment planning for protons and ions in the future by transferring clinical RBE knowledge between ions.
Kinetic mechanism and sub-ns measurements of the thermal spark in air
Authors: Minesi Nicolas Q , Mariotto Pierre B , Pannier Erwan , Vincent-Randonnier Axel , Stancu Gabi Daniel , Laux Christophe O
Published: April 2023

This experimental and numerical study is focused on the formation of fully ionized plasmas in ambient air by nanosecond pulsed discharges, namely the thermal spark. The first contribution of this article is the experimental characterization of the electron number density during the pulse. An increase of the electron number density up to 1019 cm−3 was measured with sub-nanosecond resolution via three techniques based on optical emission spectroscopy (OES): Stark broadening of H
α
, Stark broadening of N+/O+, and the continuum emission of electrons. The discharge diameter is measured with sub-nanosecond resolution using calibrated OES of the N+ and O+ lines. All measurements indicate a transition to a micrometric-size filament of fully ionized plasma in approximately 0.5 ns. The second main contribution of this work is the development of a 0D kinetic mechanism to explain this observation. The mechanism includes 100 reactions, 12 species, and 12 excited electronic states. Particular attention is paid to modeling the N2, N2
+, N, and O electronic state kinetics using the electronic states as additional pseudo-species. Our results show that including the electron-impact ionization of the excited electronic states of N and O, in addition to those of N2, is necessary to explain the experimental results, emphasizing the key role of excited state kinetics in the thermal spark formation.
R&D of on-board metal-insulation REBCO superconducting magnet for electrodynamic suspension system
Authors: Liu Shixian , Wang Lei , Chen Yong , Wang Luzhong , Zhou Benzhe , Hu Xinning , Cheng Junsheng , Wang Qiuliang
Published: April 2023

Metal-insulation (MI) REBCO high-temperature superconducting (HTS) magnet has the advantages of short charging delay, low contact losses, and self-protection abilities, which shows important application prospects in many fields. Recently, Institute of Electrical Engineering, Chinese Academy of Sciences developed a prototype on-board MI HTS coil used for electrodynamic suspension (EDS) system working with an acceleration of beyond 8 g. To design a reliable engineering on-board magnet, specific Ic
angle dependence data of short sample under different fields were fully considered to estimate the operating margin and losses accurately of the on-board magnet. A semi-analytical method, combination of the dynamic circuit method and finite element method, was used to analyze the dynamic electromagnetic force distribution inside the on-board magnet under motion state, in which the effect of the propulsion coils and the figure-eight-shaped coils were taken into considerations. Finally, a full-size MI double pancake racetrack coil was fabricated and tested in a liquid nitrogen bath. The test results meet the design requirements and verify the feasibility of the design, which provides an important reference for the experiment of on-board EDS with high acceleration in the future.
Factors influencing the electromagnetic transmission of mercury vapor discharge plasma tube arrays
Authors: Liu Rubing , Peng Jun , Lin Liguang , Qiu Dianqing , Liu Zhen , Lin Qi
Published: April 2023

Low-pressure Mercury vapor discharge plasma tubes were used to form arrays to control electromagnetic transmission. The internal and external factors influencing a discharge tube array were adjusted to expand the electromagnetic wave manipulation ability. The plasma electron density (n
e) is the key parameter for electromagnetic wave manipulation. Microwave transmission was used to diagnose n
e under different working conditions. Simulations and electromagnetic transmission measurements were used to investigate the behavior of the effect of internal and external factors on electromagnetic transmission. Simulation results indicated that increasing n
e increased the attenuation, widened the attenuation bandwidth, and shifted the attenuation band to higher fRequencies. The experimental results showed that increasing the discharge power significantly increased n
e and widened the strong attenuation frequency band. n
e first increased and then decreased when the gas pressure was increased. The tube diameter affected both n
e and the plasma layer thickness, and the attenuation band of the plasma tube array moved to a low frequency with an increase in tube diameter. The primary and secondary order of the influence of external factors other than power on the attenuation bandwidth obtained via an orthogonal experiment is as follows: gas composition > tube diameter > pressure. The maximum attenuation bandwidth for 10 dB attenuation was 9.85 GHz. The results show that the attenuation control ability of the plasma tube array can be significantly improved by adjusting the external factors of the plasma tube.
Computational modelling of light-matter interaction in aSi with CdSe/ZnS core/shell quantum dots and metal nanoantenna for solar cell applications
Authors: Rodhuan Mirza Basyir , Abdul-Kahar Rosmila , Ameruddin Amira Saryati , Mohd Rus Anika Zafiah , Tay Kim Gaik
Published: April 2023

As the world population rises, energy needs are become critical. Using photovoltaic technologies like amorphous silicon solar cells (aSiSC) to harvest solar power might benefit global concern. Previous research claimed that aSiSCs were modest short-wavelength absorbers. Quantum dot (QD) may be applied to the aSiSC to enhance optical absorptions and electric fields as the QD’s bandgap is tunable, which can cover a broader electromagnetic range. This study aims are to design the 3D aSiSC with QD on the model and to investigate the optical absorption peak, electric field profiles, and light–matter interaction of the models via COMSOL Multiphysics software. From the base model, the optical absorption improved from 736 nm at 41.827% to 46.005% at 642 nm for the aSiQDSC model which developed with 0.5/3.0 nm radius of core/shell cadmium selenide/zinc sulphide (CdSe/ZnS). This study proceeded combining rectangular nanosheets gold and silver nanoantenna (Au and Ag NA) with various gap g of NA to the aSiQDSC models where g = 0.5 nm Ag NA model was presented the higher optical absorption of 47.246% at 650 nm, and electric fields of 2.53 × 1010 V nm−1. Computationally, this ultimate design is ecologically sound for solar cell applications, which allow future direction in renewable energy research and fabrication.