Search Results (492)

Managing vehicle speeds in rural-to-urban transition zones—where two-lane roads traverse small population centres—remains a critical challenge for road safety engineering. While various traffic calming measures (TCMs) are employed to enforce speed limits, empirical evidence comparing their relative effectiveness in sequential applications is often limited. This study presents a field analysis conducted on the BI-2604 road in Gordexola (Spain). Using radar counters at 24 sequential control points, a dataset of 23,021 valid vehicle passages was analysed to evaluate seven distinct calming configurations. The results indicate that, within this corridor, purely visual countermeasures were associated with high non-compliance: standard crosswalks (paint only) recorded a non-compliance rate of 92.9%, while the Speed Monitoring Display (SMD) registered a 72.1% violation rate. Regarding physical measures, a safety–compliance paradox was identified. Speed humps located in 50 km/h zones achieved the highest statistical compliance (41.7% violation). However, raised crosswalks in 30 km/h zones, despite registering higher non-compliance (63.6%), achieved the lowest mean speeds (approximately 34 km/h; V85 ≈ 45 km/h), a range that the previous literature associates with lower pedestrian injury risk. The findings suggest that, within the investigated corridor, physical vertical deflection was associated with lower speeds than the analysed visual/signalling measures, although it remains an imperfect solution that generates significant negative externalities (noise, emissions, and discomfort) and fails to guarantee strict legal adherence to 30 km/h limits. These limitations highlight the urgent need for alternative solutions, setting the stage for future research on optimised perceptual countermeasures. Full article

Automatic Modulation Classification (AMC) aims to automatically identify modulation types based on the features of received signals, and acts as a vital technique for spectrum sensing, cognitive radio and electronic countermeasures. However, existing methods generally overlook the issue that modulation signals with similar characteristics are prone to confusion. In particular, under strong interference conditions, feature distributions become blurred and class boundaries tend to overlap, further exacerbating misclassification among modulation types with similar characteristics, thereby limiting improvements in classification accuracy and model robustness. To address this challenge, a modulation classification method based on fuzzy sample feature enhancement is proposed. Specifically, a modulation class entropy constraint and a fuzzy sample feature enhancement constraint are introduced to establish a Multi-scale Fuzzy Sample Feature Enhancement Framework (MTFSFEF). Through fuzzy sample selection and feature representation refinement, the proposed framework effectively mitigates feature overlap among fuzzy samples and enhances inter-class separability and discriminability. For $\mathrm{SNR}\ge 0\mathrm{dB}$, MTFSFEF delivers superior average classification accuracies across all three benchmark datasets: $92.82\%$ on RML2016.10a, over $93.43\%$ on RML2016.10b, and exceeding $92.78\%$ on RML2018.01a, outperforming existing methods by up to $2.68\%$, $2.89\%$, and $2.73\%$, respectively. Full article

Background/Objectives: Opioids inhibit breathing that can lead to fatal overdose, highlighting the need for testing effective countermeasure agents and potential mechanisms of action. Here we examined the role muscarinic cholinergic receptors play in the ability of L-cysteine ethyl ester (L-CYSee) to overcome the deleterious effects of morphine on ventilatory parameters in male Sprague Dawley rats and the ventilatory responses during a subsequent hypoxic-hypercapnic (HH) challenge. Methods: Ventilatory parameters were measured by whole body plethysmography. Results: The injection of the muscarinic receptor antagonist, atropine (1.0 mg/kg, IV), elicited an array of ventilatory responses (e.g., an increase in frequency of breathing coupled with a fall in tidal volume). Injection of morphine (10 mg/kg, IV) to vehicle-treated rats elicited a depression of breathing, including sustained decreases in tidal volume, minute ventilation, peak inspiratory flow, and peak inspiratory and expiratory drives, which were associated with marked increases in end inspiratory pause (EIP) and end expiratory pause (EEP), expiratory flow at 50% expired tidal volume (EF₅₀), and rate of achieving peak expiratory flow (Rpef). Most effects of morphine (10 mg/kg, IV) were not altered in atropine-treated rats, except that increases in EIP, EEP and Rpef were reduced. Subsequent injections of L-CYSee (2 × 500 μmol/kg, IV given 15 min apart) overcame the adverse actions of morphine on ventilatory parameters in vehicle-treated rats. The effects of L-CYSee, such as reversal of the effects of morphine on frequency of breathing, tidal volume and minute ventilation, were markedly reduced in atropine-treated rats. The ability of L-CYSee to reverse the adverse effects of morphine to a HH gas challenge was markedly diminished in atropine-treated rats. Conclusions: These findings demonstrate that muscarinic receptors play a vital role in the ability of L-CYSee to overcome the deleterious effects of morphine. Full article

The inherent genomic plasticity of RNA viruses, particularly influenza viruses and SARS-CoV-2, poses a major obstacle to the establishment of durable herd immunity. This challenge is further compounded by immune imprinting, whereby prior antigenic exposures bias subsequent responses toward previously encountered epitopes at the expense of effective recognition of antigenically drifted variants. In this review, we delineate the mechanistic basis of immune imprinting, with emphasis on the competitive dominance of cross-reactive memory B cells (MBCs). We discuss how the rapid “back-boosting” of these pre-existing clones can limit de novo priming of naïve B cells—through epitope masking and competition for antigen and T follicular helper cell support—thereby diverting germinal center selection and affinity maturation away from variant-specific de novo epitopes and promoting viral immune escape. To address this challenge, this article further reviews the characteristics of immune imprinting responses in influenza viruses, coronaviruses, and dengue virus, as well as corresponding countermeasures, providing a theoretical basis and new avenues for intervention to address immune imprinting induced by rapidly mutating RNA viruses. Full article

Soil salinization represents one of the most severe abiotic constraints on global forest productivity. Populus, the most widely cultivated fast-growing timber tree and a premier model woody plant, exhibits striking intrageneric variation in salt tolerance—from the extremely halophytic Populus euphratica to highly salt-sensitive cultivated clones. Understanding the molecular basis of this variation has profound implications for saline–alkali land reclamation and salt-tolerant variety breeding. This review systematically synthesizes current knowledge on Populus salt-stress responses, covering three primary injury mechanisms (osmotic stress, ionic toxicity, and oxidative damage) and the corresponding physiological countermeasures. We further survey functional genes across four major categories: ion transporters, osmotic-adjustment enzymes, antioxidant-defense components, and transcription factors. Crucially, we extend beyond the herbaceous-plant paradigm by examining salt-tolerance strategies that are specific to the woody architecture of Populus: long-distance radial and axial Na⁺ transport through tall stems, salt sequestration in senescent bark and wood parenchyma, and deep-root ion exclusion strategies. Comparative insights from other woody genera are incorporated to highlight convergent and divergent mechanisms. On this basis, we propose an integrated multi-level regulatory model in which Na⁺ compartmentalization/efflux serves as the core, ROS homeostasis as the key regulatory axis, and osmotic adjustment as the auxiliary strategy. Outstanding challenges—including unresolved primary salt-signal perception, insufficient pathway integration, and limited in planta gene-function verification—are critically assessed, and future research priorities encompassing multi-omics integration, CRISPR-based gene editing, and natural-population genomics are outlined. Full article

Deep learning models have achieved remarkable performance in radar jamming recognition, yet they remain highly vulnerable to adversarial attacks—small, carefully crafted perturbations that cause misclassification—posing a critical threat to intelligent electronic countermeasure systems. Existing adversarial defenses suffer from an inherent accuracy–robustness tradeoff, limited defensive knowledge sources, and poor generalization to unseen attacks, while the additional challenge of model lightweighting for resource-constrained radar platforms remains largely unaddressed. This paper proposes Adversarial Distillation Defense (ADD), a training framework that synergistically integrates adversarial training with knowledge distillation to produce lightweight yet robust jamming recognition models. In ADD, an adversarially pre-trained teacher model simultaneously transfers its classification knowledge on clean samples and defensive knowledge on adversarial samples to a compact student model through four complementary loss terms. Extensive experiments on a simulated dataset comprising seven radar jamming types demonstrate that ADD achieves the strongest defensive performance among the compared defenses under both white-box and black-box attacks across varying perturbation strengths and jamming-to-noise ratios. Feature-space visualization further confirms that ADD enables the student model to maintain well-separated class clusters even under strong adversarial perturbations. These results indicate that ADD offers an effective strategy for building secure and lightweight deep learning models for radar jamming recognition. Full article

Phytophthora and allied oomycete pathogens pose a perennial challenge to global food security through their devastating impact on crop systems. While metalaxyl has demonstrated remarkable efficacy in controlling Phytophthora diseases since its introduction decades ago, the persistent emergence of metalaxyl-resistant strains has severely compromised its field efficacy. Elucidating the genetic determinants underlying resistance mechanisms is critical to developing surveillance strategies and sustainable countermeasures against evolving oomycete resistance. Through experimental evolution, we generated six metalaxyl-resistant Phytophthora sojae mutants exhibiting extreme resistance levels (resistance factor > 2000). Comparative whole-genome re-sequencing of resistant mutants versus the wild-type parental strain identified 64 candidate genes containing conserved nonsynonymous mutations across all resistant lineages. Among these, PsALG8, encoding a putative alpha-1,3-glucosyltransferase, was identified as the primary determinant, carrying a recurrent homozygous missense mutation across all resistant lineages. CRISPR/Cas9-mediated knockout of PsALG8 in both wild-type and resistant backgrounds significantly reduced metalaxyl tolerance (p < 0.01), confirming its functional involvement in resistance modulation. These results suggest that PsALG8 is associated with metalaxyl sensitivity and mycelial growth in P. sojae under laboratory conditions. The conservation of ALG8 homologs suggests that PsALG8 may have a conserved cellular function related to protein glycosylation across eukaryotes. Although this glucosyltransferase is universally conserved among oomycete species, whether its association with metalaxyl sensitivity constitutes a shared resistance adaptation pathway still requires extensive functional validation in diverse Phytophthora pathogens, which may offer insights into future fungicide resistance management strategies in P. sojae. Full article

Human spaceflight in microgravity induces profound physiological adaptations, yet its effects on the sensory system remain comparatively underexplored. While musculoskeletal and cardiovascular changes are well documented, sensory alterations pose equally important challenges to astronaut safety, performance, and post-mission recovery. Calcium ions (Ca²⁺), as universal intracellular messengers, play central roles in sensory transduction, neurotransmitter release, and adaptive signaling across all sensory modalities. Emerging evidence suggests that microgravity may influence Ca²⁺ homeostasis and Ca²⁺-dependent cellular processes, potentially affecting the functional integrity of sensory pathways. In this review, we synthesize current findings on the impact of microgravity on Ca²⁺-dependent processes in the five classical senses. Evidence from spaceflight studies, ground-based analogs, and related physiological models suggests possible alterations in taste receptor signaling, Ca²⁺-binding protein expression, mechanotransduction pathways, and vestibular function. However, direct evidence for microgravity-induced disruption of Ca²⁺ signaling remains limited for several sensory modalities. Collectively, these changes are associated with altered taste and smell perception, visual disturbances, reduced tactile sensitivity, and vestibular imbalance. By integrating both direct evidence and mechanistic hypotheses across sensory systems, this review highlights Ca²⁺ signaling as a potential unifying mechanism underlying sensory adaptation to microgravity. We further identify key knowledge gaps and discuss potential directions for developing targeted countermeasures aimed at preserving sensory function during long-duration missions. Beyond spaceflight, these insights contribute to a broader understanding of Ca²⁺-mediated sensory physiology under extreme environmental conditions. Full article

Unloading-induced bone loss is a major medical challenge during long-duration human spaceflight, largely driven by suppressed osteoblast-mediated bone formation, and practical countermeasures are needed. Electromagnetic stimulation has shown benefits for bone repair, and its non-invasiveness supports potential space use; however, its single-modality efficacy remains limited. Here, we investigated a combined electromagnetic field (CEMF) integrating a static magnetic field (SMF, 0.4–0.6 T) and a pulsed electromagnetic field (PEMF, 0.38 ± 0.19 mT) to attenuate unloading-related bone loss and examine field-induced mechanical stimulation. Finite-element simulations mapped magnetic flux density, field gradient, induced current density, and Lorentz force density in bone tissue. CEMF was evaluated in vivo in hindlimb unloading (HLU) mice and in vitro in MC3T3-E1 osteoblasts. CEMF improved bone mineral density, trabecular and cortical microarchitecture, and mechanical properties in HLU mice, with increased osteoblast number and mineral apposition rate. In vitro, CEMF promoted osteogenic differentiation and upregulated COL1A1 and RUNX2. Transcriptome analysis suggested activation of ECM–integrin mechanical signaling and the PI3K–AKT pathway. These findings indicate that CEMF-induced multiphysics stimulation enhances osteogenic responses and may serve as a complementary, non-invasive countermeasure for spaceflight-associated bone loss. Full article

Background: Long-duration spaceflight (LDSF) poses unique challenges to ocular health as microgravity, radiation, and environmental changes can cause lasting visual and structural impairments that affect astronaut performance. Objective: This review synthesises current evidence on in- and post-flight ocular complications. It integrates clinical findings, terrestrial analogues, animal studies, and theoretical models to characterise the pathophysiology, risk factors, and countermeasures associated with spaceflight-induced ocular changes. Methods: A review of peer-reviewed literature was conducted, focusing on dry eye disease, corneal edema, ocular biometric shifts, spaceflight associated neuro-ocular syndrome (SANS), and radiation-induced cataractogenesis. Data from in-flight imaging, post-flight assessments, and ground-based analogues were analysed. Results: Spaceflight induces multifactorial ocular changes, including tear film instability, optic disc edema, posterior globe flattening, and hyperopic refractive shifts. These effects are thought to result from cephalad fluid shifts compartmentalised cerebrospinal fluid pressure, venous congestion, and impaired glymphatic system. Long-term risks, such as cataractogenesis, are linked to radiation exposure and genetic susceptibility. Although several countermeasures are being explored, no single approach fully prevents these complications. Conclusions: Ocular complications during LDSF remain a significant challenge for astronaut health and mission performance. A multimodal approach combining mechanical, nutritional, and diagnostic strategies will be essential for future exploration-class missions. Further research is needed to refine countermeasures and preserve astronauts’ visual function. Full article

Radiation-induced intestinal injury (RIII) is a common complication of tumor radiotherapy, significantly impacting patients’ quality of life and posing challenges for developing effective medical countermeasures. This study investigated the reparative effects of the traditional Chinese medicine Pyrrosia petiolosa (Christ) Ching on radiation damage through in vivo and in vitro models. By integrating gut microbiota and untargeted metabolomics analyses, it elucidated the multidimensional mechanisms through which P. petiolosa regulates the microbiome as well as metabolic homeostasis. In vitro experiments demonstrated that P. petiolosa effectively suppressed radiation-induced inflammatory factors (IL-6, TNF-α, and IL-1β) and alleviated radiation-induced oxidative stress (MDA, GSH, and SOD). In vivo models further confirmed that P. petiolosa significantly alleviated radiation-induced intestinal inflammation and leukopenia, while protecting the structural and functional integrity of mouse small intestinal crypt villi. Mechanistic studies revealed P. petiolosa reshaped the gut microbiota by promoting enrichment of beneficial bacteria such as Bacteroides, concurrently restoring the homeostasis of key metabolic pathways, including glutathione, glycerophospholipids, and the tricarboxylic acid cycle. Analysis of the microbiome–metabolome interaction network revealed that treatment with P. petiolosa altered the correlation patterns between gut microbiota and fecal metabolites, including potentially beneficial bacteria and metabolites associated with inflammatory and oxidative stress responses. These findings suggest that microbiome–metabolome remodeling may contribute to the protective effects of P. petiolosa against radiation-induced intestinal damage. Overall, this study provides preliminary evidence that P. petiolosa may alleviate acute radiation-induced intestinal damage through anti-inflammatory and antioxidant effects accompanied by changes in gut microbiota and metabolic homeostasis, while identifying candidate targets for future functional validation. Full article

In response to increasingly complex risks and challenges and to safeguard national agricultural product supply security, this study constructs a four-dimensional evaluation index system encompassing “Resistance-Adaptation-Recovery-Innovation”. Utilizing panel data from 30 provincial-level regions in China from 2017 to 2023, and employing a comprehensive methodology including the entropy method, Dagum Gini coefficient, Markov chain, kernel density estimation, and convergence models, this research measures the resilience of China’s agricultural product supply chain and investigates its spatiotemporal evolution patterns. The findings are as follows: Firstly, the resilience level of the national agricultural product supply chain shows overall steady improvement, but regional development is uneven, presenting a pattern of eastern regions leading, central regions maintaining steady progress, and western regions catching up. Secondly, the overall resilience difference is strongly correlated with regional variability, with the most pronounced internal disparity observed in the western region. Thirdly, the evolution of resilience exhibits path dependency characterized by the coexistence of a “low-level trap” and “high-level stability”, and less developed regions demonstrate a significant “catch-up effect” towards their more developed counterparts. Based on these findings, this study proposes countermeasures such as implementing targeted policies for different regions, establishing cross-regional coordination mechanisms, strengthening dynamic monitoring and early warning systems, and promoting innovation-driven development and structural upgrading. These efforts aim not only to enhance China’s capacity to respond to risks in its agricultural product supply chain and ensure national food security, but also to provide valuable insights for other countries facing similar challenges in building resilient agricultural systems in an increasingly uncertain global environment. Full article

In air-to-air counter-UAV scenarios, vision–language tracking for tiny drones still lacks a dedicated benchmark. Unlike traditional UAV tracking or ground-based Anti-UAV settings, air-to-air counter-UAV tracking involves simultaneous motion of both the tracking platform and the target platform. In addition, the target typically appears as a tiny object and is subject to rapid viewpoint changes, fast background transitions, and interference from similar drones, making it difficult to systematically assess the capability boundaries of existing methods. To address this gap, we present the ATA dataset. To the best of our knowledge, ATA is the first vision–language tracking dataset specifically designed for real air-to-air tiny-object UAV countermeasure scenarios. ATA contains 50 real-flight video sequences with 38,094 frames in total, and provides frame-wise bounding box annotations together with video-level English language descriptions. It supports two unified task settings, namely BBox-only and Language-assisted tracking. The dataset covers diverse real-world low-altitude scenarios with complex backgrounds. Notably, the average target area accounts for only $0.03\%$ of the full image, exhibiting pronounced tiny-object characteristics. ATA also captures several key challenges in this setting, including dual-dynamic disturbances, complex background changes, and multi-drone interference. Based on ATA, we establish a benchmark covering both vision-only and vision–language tracking methods, and conduct a systematic evaluation of eight representative recent trackers. Experimental results show that current mainstream methods still perform unsatisfactorily in this scenario, with evident limitations in tiny-object representation, cross-frame association, robustness to complex backgrounds, and interference suppression. Furthermore, we validate a lightweight temporal enhancement module, AFTE, and show that explicitly leveraging adjacent-frame information consistently improves the performance of multiple baseline models. Overall, ATA provides a unified benchmark for vision–language tracking in air-to-air counter-UAV scenarios of tiny drones and highlights temporal modeling as a promising direction for improving tracking performance in this challenging setting. Full article

Cutaneous Radiation Injuries (CRIs) and wounds within an area of radiation exposure (combined injury, CI) are a significant concern for nuclear accidents and radiation combat/terrorist events. CRIs and CI present unique clinical challenges, and effective countermeasures are urgently needed. Here we describe a murine model of CRI and CI in C57BL/6 mice using 16.9 Gy thoracic X-ray irradiation (5.3 Gy/min, 160 kV) ± experimental wound administered immediately. Wound repair and radiation-induced dermatitis were assessed after irradiation. Our previous studies showed that genistein (200 mg/kg, s.c.), administered 24 h prior to irradiation prevented radiation injuries in two murine models. We investigated the effects of genistein in the CI model. Macroscopic and histological analyses showed that radiation significantly delayed wound closure, although wounds did not significantly alter the progression of radiation dermatitis. Genistein improved the early rate of wound closure and significantly reduced dermatitis in mice. Histological analysis showed that genistein improved skin structure and reduced inflammation and fibrosis. Immunohistochemistry showed that genistein attenuated radiation-induced cyclin-dependent kinase inhibitor 1 (p21/waf1) and α-smooth muscle actin and preserved K15 positive skin adult stem cells. These findings suggest that genistein may be an effective prophylactic against CRIs and CI. Full article

Collaborative driving, in which autonomous vehicles cooperate with other vehicles and roadside infrastructure to improve safety, perception, and traffic efficiency, is emerging as a key paradigm for next-generation transportation systems. While such collaboration enhances situational awareness, it also introduces new security vulnerabilities across perception, communication, planning, decision-making, and control layers. In this survey, we present a unified taxonomy of security threats and defense mechanisms in collaborative driving systems, systematically organizing attacks and countermeasures across system layers. We further examine the integration of language models, including vision-based and multimodal reasoning models, into collaborative driving pipelines, highlighting the resulting security risks and design challenges. Finally, we identify key open research challenges, including cross-layer and end-to-end security, uncertainty-aware defenses, and real-world validation, outlining promising directions for future work toward secure and resilient collaborative autonomous mobility. Full article