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Machine learning–assisted performance prediction of graphene–silicon twin-port band-notched wideband antenna for THz 6G communication systems
Abstract A graphene–silicon-based twin-port terahertz (THz) antenna is proposed and investigated in this work. The antenna employs an aperture-coupled asymmetric ring dielectric resonator configuration to achieve wideband operation in the THz regime. Circular metallic rings integrated with the printed feed structure introduce a band-notch characteristic between 2.75 THz and 3.15 THz for interference suppression. A graphene coating is incorporated to provide frequency tunability, while DGS is utilized to reduce mutual coupling between the antenna ports. The proposed antenna operates efficiently over the 2.2–2.65 THz and 3.3–3.7 THz frequency bands with isolation levels below − 25 dB. The antenna also exhibits stable radiation characteristics, low envelope correlation coefficient (ECC), high diversity gain (DG), low channel capacity loss (CCL), and acceptable total active reflection coefficient (TARC), confirming its suitability for THz MIMO communication systems. Furthermore, deep neural network (DNN) and random forest (RF) ML approaches are employed to predict the |S 11 | characteristics of the antenna using a large parametric dataset generated through full-wave electromagnetic simulations. The ML models are evaluated using MAE, MSE, RMSE, Variance Score, and R² metrics, demonstrating strong agreement between predicted and simulated results. The proposed antenna provides a compact, tunable, and ML-assisted THz communication solution suitable for future intelligent 6G wireless applications.
Orbitofrontal noradrenaline supports adaptive learning-rate adjustment in probabilistic reversal learning
Adaptive decision-making in dynamic environments requires flexible adjustment of learning speed to balance stability and flexibility. When outcomes are highly stochastic, learners must avoid over-interpreting noise and update more slowly, whereas in volatile environments where contingencies change frequently, learning should accelerate to rapidly incorporate new evidence. Theories propose that internal estimates of uncertainty tune learning rates through neuromodulation-dependent mechanisms. Here, we investigated how noradrenergic inputs from the locus coeruleus (LC) to the orbitofrontal cortex (OFC) support adaptive learning under uncertainty. We show that, in a probabilistic reversal learning task performed across different levels of stochasticity, rats exhibited behavior best explained by an adaptive reinforcement-learning model in which learning rates dynamically adjusted according to model-estimated stochasticity and volatility, outperforming standard fixed-rate models. Noradrenaline release in the OFC closely tracked trial-by-trial, model-derived volatility estimates around contingency changes. Disrupting LC→OFC noradrenergic inputs reproduced the model-predicted impairment in adaptive learning-rate adjustment associated with model-estimated volatility. Together, these findings identify OFC noradrenergic signaling as a key circuit mechanism supporting learning-rate adjustment in response to internal estimates of volatility during adaptive decision-making under uncertainty.
Research and application of precision three-dimensional drilling for stress relief and surrounding rock control in high-stress roadways
Inhibitory modulation of age-dependent behavior through <i>dsx</i> -expressing cells in honeybees
Social insects exhibit distinct age-dependent behavioral repertoires that collectively contribute to the common benefits of a colony. However, how the nervous system manifests the capacity of such age-dependent, disparate behavioral repertoires underlying the division of labor is largely unknown. In honeybee ( Apis mellifera ), a classical model of such age-dependent polyethism, young but not older worker bees attend and feed the queen (retinue behavior), which is triggered by the queen mandibular pheromone (QMP). Here, we revealed that older bees are still equipped with a latent QMP retinue response that is, however, modulated by the electrical activity of doublesex -expressing ( dsx + ) cells. We genetically expressed a designed neuron silencer hM4Di protein from the endogenous dsx promoter. We conditionally activated this receptor protein by feeding or not feeding the synthetic ligand C21. Eight- to 11-day-old worker bees displayed a retinue-like QMP response under electrical silencing conditions (+C21) but not under nonsilencing conditions (−C21). Control experiments demonstrated that the administration of the ligand C21 could not account for the observed increase in retinue behaviors in older bees, which is otherwise only observed in younger bees. Our study suggests an inhibitory role of dsx + cells of age-dependent retinue behaviors and establishes an unexplored connection between polyethism and its manifestation in the nervous system. Hence, chemogenetically driven manipulations suggest inroads for examining the division of labor at the level of neuronal activity.
Multi-camera vision-based structural health monitoring of historic masonry minarets with LLM/VLM-assisted damage interpretation
Experimental drought drives divergent succession of soil microbiota
As droughts become increasingly severe and prolonged worldwide, understanding how belowground biodiversity changes over time under water limitation is critical for assessing ecosystem resilience. However, long-term and continuous observations of soil microbial responses to drought remain rare. Here, using a 6-y experimental drought in a tallgrass prairie ecosystem, we showed that experimental drought reshaped the community compositions of soil bacteria, fungi, and protists, accompanied by progressive declines in microbial diversity and biomass. Analyses of time–decay relationships and paired community differences between drought and ambient conditions revealed increasingly divergent successional trajectories of soil microbiota under drought. Although stochastic processes dominated community assembly overall, their relative importance declined over time, particularly for bacteria in drought-treated soils, suggesting increasingly strong deterministic environmental filtering imposed by drought. In addition, drought reduced microbial network size but increased the complexity and stability of bacterial networks by favoring drought-tolerant taxa. Furthermore, drought-driven shifts in microbial community compositions significantly altered functional genes and associated ecosystem functioning. These findings suggest that microbial communities may become less variable but more vulnerable, and the detrimental effects of biodiversity loss on ecosystems could be more severe in an increasingly drought-prone world.
Exercise interventions improve landing error scoring system scores in athletes: a systematic review and meta‑analysis
Uninterrupted optical resolution of identical point scatterers undergoing nanometric changes in distance
In established superresolution fluorescence microscopy or nanoscopy, resolving identical fluorescent molecules at subdiffraction distances requires the molecules to emit sequentially so that they briefly become discernible from their neighbors one after another. Simultaneous tracking of multiple fluorophores that are only a few nanometers apart is thus conceptually and practically impossible. We have recently shown that probing a subdiffraction region with an excitation beam featuring an intensity zero, i.e., MINFLUX superresolution, localizes and resolves closely packed identical fluorophores without interruption. Here, we provide a conceptual framework for resolving and tracking constantly emitting identical fluorophores—more generally, point scatterers—that undergo random changes in position. In particular, we show that the detection rates available in fluorescence microscopy are sufficient to track sub-10 nm distance changes within micro- to milliseconds. By using a DNA origami construct with a fixed and a movable fluorophore as a proxy, we provide a proof-of-concept that thermally driven conformational changes of macromolecules are continuously detectable with visible light. Conformational changes of the DNA nanostructure leading to random jumps in distance of about 10 nm between two labels are registered within ~1 ms. Our work paves the way toward superresolving complex conformational transitions of individual biomolecules with focused light.
Exploring handstand walking biomechanics and shoulder pain
Abstract Handstands are a key skill in many specialist sports involving the use of upper limbs in a role usually associated with lower limbs. Handstand sports have a high incidence of pain in the shoulder, but with little understanding of handstand walking biomechanics. We aimed to explore the biomechanics of handstand walking in athletes with and without shoulder pain to assess underlying differences across whole limb function. Ten participants, who could handstand walk 6 steps, had force and positional data collected. Shoulder pain was assessed via questionnaire. Forces, centre of mass position, velocities, axial and torsional work, mechanical energy, and overall arm parameters were calculated from 237 stance phases. Two-way ANOVA assessed differences between participants with and without shoulder pain and arm (Right/Left). Participants with shoulder pain moved significantly slower ( p = 0.005), exhibited shorter arm lengths ( p = 0.013) and had greater net torsional work ( p = 0.002) resulting in a lower axial–torsional work ratio. Altered handstand biomechanics in participants with pain demonstrate a more flexed position of the arm, often linked with higher joint loading. Handstand walking mechanics appear to closely resemble groucho-running enabling longer double support reducing limb loading on fatigable upper limbs. Future studies should account for confounders including disciplines, training volume, and gender, providing insight into the implications for upper limb full body loading.
Finding Turing islands through dynamical exploration
A green synthesis of Sm doped NiO nano catalyst as dual functional material for photocatalytic degradation and electrochemical sensing
Internal stress controls tendril writhing dynamics in climbing plants
We present experimental results on the writhing dynamics of cucumber plant tendrils subjected to an axial traction force. At low forces, the tendrils’ curvature saturates exponentially in time at a limiting value. At forces higher than the critical threshold, the tendril fails to coil but develops an intrinsic coiling-prone stress, corresponding to an intrinsic residual curvature, visible if the load is released. Growth-field assessments indicate that curvature arises from differential growth. To understand these experiments we develop an autotropic morphoelastic growth model with a bi-strip geometry, in which one strip undergoes mechanosensitive growth. In the absence of an external load, curvature generation is solely limited by internal stresses. To link the actual curvature to a finite external force, the tendril is approximated as a Kirchhoff rod. The resulting model reproduces the two observed regimes: below the critical axial force, the tendril coils, and above this force, the tendril remains straight but still exhibits intrinsic curvature.
Deep behavioral phenotyping reveals novel features in a mouse model of metabolic dysfunction-associated steatohepatitis
Reading taste in a bee’s face
Forearm muscle and nerve morphology differs by sex and predicts climbing style in recreational climbers
Imaging predictors of short term clinical response to osteopathic manipulative treatment in patients with knee osteoarthritis
Role of Pbr1, a putative oxidoreductase, in the ER quality control and folding of yeast Fks1 glucan synthase
The biogenesis of multipass membrane proteins challenges the endoplasmic reticulum (ER) quality control, particularly when transmembrane segments contain polar or charged residues required for function. Fks1, the catalytic subunit of yeast β-(1,3)-glucan synthase, exemplifies this challenge because its large multipass transmembrane architecture must support glucan synthesis at the plasma membrane while also undergoing efficient biogenesis in the ER. Here, we investigate the cellular role of PBR1 ( YNL181W ), an essential gene whose role remains uncharacterized even though its predicted product has similarity to oxidoreductases. By integrating quantitative morphological profiling with global genetic interaction analysis, we found that PBR1 function converges on cell-wall biosynthesis and closely parallels that of FKS1 . Partial loss of Pbr1 function caused temperature-sensitive growth defects but also impaired β-(1,3)-glucan synthesis, and weakened cell-wall integrity. Under these conditions, Fks1 failed to accumulate at the cell surface and, instead, accumulated in ER-associated compartments, where it exhibited reduced stability. Biochemical analyses revealed the accumulation of immature Fks1 species, including forms defective in glycosylation, consistent with compromised ER quality control. A spontaneous missense suppressor allele of FKS1 partially restored Fks1 stability and growth, supporting a functional relationship between the two proteins. Pbr1 is a cytosol-facing ER membrane protein that physically associates with Fks1, and structural modeling suggests that it adopts a Rossmann-like fold capable of binding pyridine nucleotides despite divergence from canonical catalytic motifs. Together, these findings identify Pbr1 as an ER-associated, chaperone-like factor required for the folding and maturation of Fks1.
Visualizing Dolichogenidea gelechiidivoris parasitism within Tuta absoluta larvae through fluorescence microscopy in optically cleared samples
Zero-deforestation commitments in Indonesia’s palm oil sector achieve high compliance but no additionality
In response to public pressure, companies have increasingly adopted voluntary sustainable sourcing commitments. Yet, it often remains unclear whether such commitments lead only to the narrow goal of supplier compliance, or also to the broader goal of additionality, benefits beyond what would have occurred without commitments. A company’s ability to influence its suppliers’ behavior partly depends on the complexity of supply chains, yet data on supply chain linkages are limited, inhibiting causal evaluations. Here, we evaluate the compliance and additionality of zero-deforestation commitments (ZDCs) in the Indonesian palm oil sector, a major driver of tropical deforestation. We compiled a detailed dataset that integrates information about corporate ZDC implementation, supply chain linkages, and maps of palm-driven deforestation in Indonesia. We use this dataset to evaluate the causal impact of ZDCs on deforestation in oil palm concessions from 2018 to 2020 using difference-in-differences econometric methods. We find that concessions linked to companies with ZDCs had low deforestation (<1% per year from 2018 to 2020) and thus largely achieved compliance. Yet they experienced similar reductions in deforestation compared to concessions not covered by ZDCs, therefore showing no additionality. We attribute our finding of no additionality to broader changes in policy and economic conditions during the study period that may have reduced the remaining accessible forest and dampened market and regulatory incentives to clear forests for palm oil. Should these conditions change in the future, continued compliance with ZDCs could yield additional reductions in deforestation.