Browse Articles

Active learning design of bcc solid solution alloys with gigapascal strength and elemental metal–level ductility

Body-centered cubic (bcc) alloys can achieve gigapascal-level yield strengths but typically are limited in tensile ductility (<20%), contrasting sharply with elemental metals (the largest elongation of ~50%). Multi-principal-element alloys offer vast compositional space to reach synergistic strength–ductility combinations. However, combinatorial trial-and-error exploration is prohibitively costly, while machine learning (ML) approaches are hindered by data scarcity. Here, we develop an ML-guided framework integrating active learning with physics-informed Bayesian optimization to rapidly converge on optimal compositions. The resulting Ti 36 V 14 Nb 22 Hf 22 Zr 1 Al 5 alloy achieves a yield strength of 953 MPa and a large tensile ductility of 42%. The high strength arises from the substantial lattice distortion, as well as the ~1-nm-sized local chemical fluctuations (LCFs) inherent to the highly concentrated bcc solid solution. The ubiquitous LCFs also substantially promote dislocation multiplication and strain hardening, enabling a large tensile ductility. Our approach demonstrates ML’s efficacy in accelerating the finding of high-performance alloys.

The first mitochondrial genome for Sterictiphorinae (Hymenoptera: Argidae) and insights into argid phylogeny

Functional motifs in food webs and networks

When studying a complex system, it is often useful to think of the system as a network of interacting units. One can then ask if some properties of the entire network are already explained by a small part of the network, a network motif. A famous example of an ecological motif is exploitative competition in food webs, where the presence of two species competing for a shared resource precludes the existence of a stable equilibrium for the whole system. However, other examples of motifs with such direct impacts on stability are not known. Here, we show why small motifs that allow conclusions on systemic stability are rare. More importantly, we show that another dynamical property, reactivity, is typically rooted in motifs. Computing the reactivity of motifs can reveal which parts of a network are prone to respond violently to perturbations. This highlights motif reactivity as a useful property to measure in real-world systems to understand likely modes of systemic failure in food webs or other networks in epidemics, supply chains, or power grids.

Learning-aided Artificial Bee Colony with neural knowledge transfer for global optimization

Tantalum alloy–based resonators for quantum information systems

Utilizing tantalum (Ta) in superconducting circuits has led to significant improvements, such as high qubit lifetime (T 1 ) and quality factors in both qubits and resonators, suggesting that material optimization plays an important role in the development of superconducting circuits. Thus we here explore superconducting gap engineering in Ta-based devices as a powerful strategy for expanding the range of suitable host materials. By alloying 20 atomic percent (at.%) hafnium into Ta thin films, we achieve a superconducting transition temperature (T c ) of 6.09 K as observed in direct current (DC) transport measurements, reflecting an increase in the superconducting gap. We systematically vary deposition conditions to control film orientation and transport properties of Ta-Hf alloy thin films. We then confirm the enhancement in T c via microwave measurements at millikelvin temperatures. We verify the ∼ 40 % increase in T c relative to bare Ta devices, while the loss contributions from two-level systems and quasi-particles remain unchanged in the low temperature regime. These findings emphasize the promise of material engineering in superconducting circuits and point to many potential material candidates for further exploration.

Schleyer-type hyperconjugative aromaticity in CH isomers of diazoles revealed by DFT and NBO analysis

Representational drift reflects ongoing balancing of stochastic changes by Hebbian learning

Recent evidence indicates that even under stable environmental and behavioral conditions, responses to sensory stimuli undergo continuous reformatting over the course of days, a condition described as representational drift. However, the processes underlying this phenomenon remain poorly understood. Examining the dynamics of signal and noise correlations among neuron pairs in chronic calcium imaging experiments in the mouse auditory cortex, we investigate how activity-dependent, Hebbian-like plasticity and activity-independent, stochastic synaptic processes contribute to representational drift. We found that signal correlations predict future noise correlations, suggesting that stimulus-induced coactivation leads to increased effective connectivity between neuron pairs. Moreover, simple linear network models were able to account for the observed temporal dependencies between signal and noise correlations, but only if both Hebbian-like plasticity and stochastic changes of either inputs or recurrent synapses contribute to representational drift. In conclusion, our findings suggest that continuous sensory input–driven Hebbian-like plasticity can balance ongoing stochastic synaptic changes, thereby preventing the network’s functional degradation.

Comparison of epidural space contrast flow and clinical outcomes in parasagittal versus transforaminal epidural steroid injection

Abstract Epidural steroid injections (ESI) are frequently used to treat lumbosacral radicular pain, but the solute spread in the epidural space needs further investigation. This semi-blind, randomized study assessed clinical outcomes and contrast spread patterns between the parasagittal interlaminar (PIL) and transforaminal (TF) approaches in 79 adults with low back pain. Participants were randomly assigned to receive either TF-ESI (3 ml) or high-volume PIL-ESI (10 ml). All procedures were performed under fluoroscopic guidance. Contrast spread was evaluated by a blinded pain specialist, and clinical outcomes, including analgesia, patient satisfaction, and quality of life, were measured at two weeks, one month, two months, and six months post-treatment. Results showed no differences in baseline characteristics between groups. There were no statistically significant differences between the two groups in mean pain intensity at baseline and six months after treatment ( p  = 0.590 and 0.484, respectively). Pain relief, satisfaction, quality of life, and contrast spread to the anterior epidural space did not differ over six months. However, the TF group required significantly more fluoroscopic images ( p  < 0.001). High-volume PIL-ESI provides clinical efficacy and anterior contrast distribution equivalent to TF-ESI, with fewer fluoroscopic images needed.

Correction for Hou et al., Therapeutic restoration of mitochondria–endoplasmic reticulum cross talk for osteoarthritis

NMR metabolomic signatures of healthy lifestyle and incident MASLD

Evolution of sensory systems underlies the emergence of predatory feeding behaviors in nematodes

Understanding how animal behavior evolves remains a major challenge, with few studies linking genetic changes to differences in neural function and behavior across species. Here, we identify specific sensory adaptations associated with the emergence of predatory feeding behaviors in the nematode Pristionchus pacificus. While Caenorhabditis elegans uses contact-dependent sensing primarily to avoid threats, P. pacificus has co-opted this modality to support both avoidance and prey detection, enabling context-dependent predatory behavior. To uncover a potential mechanism underlying the evolution of P. pacificus prey perception, we mutated 27 canonical mechanosensory genes and assessed their function using behavioral assays, automated behavioral tracking, and a machine learning analysis of behavioral states. While several mutants showed mechanosensory defects, Ppa-mec-6 mutants specifically also impaired prey detection, indicating the emergence of a mechanosensory module linked to predatory behavior. Furthermore, disrupting both mechanosensation alongside chemosensation revealed a synergistic influence for these modalities. Crucially, Ppa-mec-6 is expressed in the environmentally exposed IL2 neurons that represent the first point of predator–prey contact. Moreover, silencing Ppa-mec-6 expressing cells induced severe predation defects validating their importance for prey sensing. Thus, predation evolved through the co-option of mechanosensory and chemosensory systems that act together to shape the evolution of complex behavioral traits.

Development of a novel dismantlable adhesive for orthodontic use triggered by thermal stimulation

Germline fate determination by a single ARGONAUTE protein in <i>Ectocarpus</i>

ARGONAUTE (AGO) proteins are a highly conserved family of RNA-binding proteins that play central roles in gene regulation and developmental processes across eukaryotes. Although AGO family members have been extensively studied in animals and plants, where they are typically encoded by multiple genes, their function in brown algae, a diverse and complex group of multicellular algae, remains largely unknown. Here, we show that the genomes of several brown algae encode only a single AGO protein, containing the conserved functional domains characteristic of the family. Using the model brown alga Ectocarpus and a combination of cell biology, genetic, and transcriptomic approaches, we demonstrate that AGO is essential for the transition from vegetative growth to sexual reproductive development and for germline establishment. Our results further suggest that AGO functions in concert with microRNAs to regulate target genes primarily at the posttranscriptional level, likely through translational repression. Ectocarpus thus represents a rare example of a complex multicellular organism that relies on a single AGO protein to regulate key developmental processes, pointing to a minimalistic model of RNA-based regulation in brown algae.

Chitosan-poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)-AuNPs composite for acetone detection using plasmonic image sensor

The kinetochore corona orchestrates chromosome congression through transient microtubule interactions

For proper segregation of chromosomes and successful cytokinesis, chromosomes must first “congress”—gather in a tight plate near the spindle equator. Molecular mechanism(s) of congression are not fully understood. Here we combine live-cell microscopy, perturbations of microtubule motor activities, correlative light/electron microscopy, and computational modeling, to quantitatively characterize the early-prometaphase movements that bring the scattered chromosomes to the equator in human RPE1 cells. We find that the early-prometaphase movements are directed toward the center of the spindle axis and not the spindle poles. Centromere velocity of the centripetal movements is not constant, with centromeres moving faster at larger distances from the spindle center. We also detect that numerous short microtubules appear at kinetochores at the earliest stages of spindle assembly and prior to chromosome congression. Computational modeling reveals that a mechanism based on brief, stochastic, minus-end directed interactions between the short microtubules protruding from the kinetochores and long appropriately curved microtubules within the spindle accurately predicts the observed distance-velocity function. Further, the model predicts that insufficient numbers of microtubules protruding from the kinetochores decreases the velocity and randomizes directionality of congression movements. These predictions match changes in the chromosome behavior observed in cells with suppressed nucleation of microtubules at the kinetochore corona (RPE1 Rod Δ/Δ ). In contrast, predictions of computational models based on continuous pulling forces at kinetochores differ significantly from the experimental observations. Together, live-cell observations and modeling reveal a mechanism that enables the efficient and synchronized arrival of chromosomes to the spindle equator.

Green synthesis and characterizations of zinc oxide nanoparticles using acorn fruit extract for antimicrobial, larvicidal and in silico activities

In situ NMR and integrative proteomics reveal the interaction signature of serum α-synuclein

Alpha-synuclein (αS) plays a central role in several neurodegenerative diseases. Although predominantly neuronal, αS is also present in peripheral fluids such as serum and cerebrospinal fluid (CSF), where it may contribute to disease propagation. However, its extracellular interactions remain poorly understood. By combining in situ NMR spectroscopy and bottom–up MS proteomics, we reveal that monomeric αS exhibits distinct interactomes in serum versus CSF. Both N- and C-terminal αS regions bind to serum components, while in CSF, αS remains largely unbound. The N- and C-terminal interactions are mechanistically diverse: C-terminal binding is electrostatic, whereas N-terminal interactions persist under high ionic strength, implicating hydrophobic interactions. Deletion of the first ten N-terminal residues, which include several hydrophobic side chains, abolishes these interactions, highlighting their functional importance. Proteomic profiling and NMR validation identify key αS serum partners, including albumin, γ-globulins, and lipoproteins, which, together, are sufficient to recapitulate the serum αS interactome and elicit redundant interactions with the αS N-terminal region. Despite such redundancy, αS methionine oxidation selectively disrupts N-terminal binding, suggesting a redox-sensitive mechanism regulating the αS extracellular interactome. Notably, C-terminal interactions are preserved when the N-terminal binding is detuned, indicating that the N- and C-termini elicit independent interactions with the extracellular matrix, a marked difference from the intracellular milieu. These findings uncover dynamic and fluid-specific αS interaction signatures, offering new molecular insights into its peripheral roles and identifying potential new epitopes as synucleinopathy biomarkers. These results are also relevant for other amyloidogenic intrinsically disordered proteins (IDPs), for which αS serves as a prototype.

An explainable hybrid CNN–transformer model for sign language recognition on edge devices using adaptive fusion and knowledge distillation

Drospondin, a glial glycoprotein with similarities to human Reelin/F-spondin, contributes to <i>Drosophila</i> brain development and function

Reelin is a secreted glycoprotein with roles in the development of the mammalian neocortex, hippocampus, and cerebellum. This vertebrate signaling molecule also contributes to adult brain function. Mammalian Reelin increases the complexity of Drosophila Mushroom Body (MB) neurites, an effect mediated by LpR1 and LpR2, the orthologs of mammalian Reelin receptors. Paradoxically, to date, no Reelin ortholog has been described in Drosophila . Here, we report that the protein product of the uncharacterized Drosophila CG17739 gene, which we named Drospondin, shares sequence homology with vertebrate F-spondin and Reelin. We show that Drospondin is expressed in glial cells and is crucial for MB development. Our results also show that Drospondin genetically interacts with LpRs and that human Reelin rescues neuronal and brain structural defects in Drospondin-deficient flies. Furthermore, Drospondin-deficient flies exhibit altered sleep, locomotion, and social behaviors. Our results reveal that Drospondin is a Drosophila protein with similar functions to mammalian Reelin/F-spondin, that has an essential role in brain development and function, the impairment of which has profound functional consequences for the animal.

The mediating role of schadenfreude between malicious envy and bullying in school

Abstract Bullying in school is a multidetermined phenomenon that becomes even more complex with the increasing relevance of social status at the onset of middle adolescence. This age - between 13 and 17 - is characterized by substantial social, emotional, and cognitive developments, implicating two negative social emotions in bullying behavior: envy and schadenfreude. Envy can be distinguished between benign envy, which involves improvement motivation, and malicious envy that leads to hostile feelings towards the envied person. Schadenfreude is defined as joy over the downfall of a rival. We propose that malicious envy is positively and benign envy negatively linked to bullying perpetration and that both effects are mediated by schadenfreude. In a preregistered study with a sample of n  = 2,172 secondary school students, we collected data across two waves to test this proposed mediation model. Neither malicious nor benign envy is directly related to bullying; however, the effect of malicious envy on bullying perpetration is fully mediated by schadenfreude. Exploratory analyses suggest that these pathways differ by gender, indicating that in girls, malicious envy only affects bullying through schadenfreude, whereas in boys, bullying is likely influenced through other processes.