The self-organization of asynchronous rhythms into synchronized beating in in vitro cardiomyocyte networks is a fundamental problem in systems biology research. Inspired by the dynamics of chemical oscillators, this paper presents a programmable model framework based on a discretized Belousov-Zhabotinsky reaction-diffusion system to study signal propagation and synchronization in cardiomyocyte networks. We propose a hybrid discrete-continuous geometry in which active excitable units (simulating cells) are embedded in a passive diffusive medium, with the dynamics of each unit governed by the Rovinsky-Zhabotinsky equations. Unlike conventional continuous media models, the present framework represents each cell as an independently programmable discrete unit, thereby explicitly capturing the discreteness and cell-to-cell variability inherent in in vitro cardiomyocyte networks. We systematically compare model simulations with in vitro experiments on neonatal rat cardiomyocyte networks using calcium imaging and mechanical stimulation. The framework reproduces multi-scale dynamical features: (i) intracellular excitation-propagation-recovery cycles, (ii) topology-dependent signal transmission in both regular and irregular networks, and (iii) the self-organized transition from cell-to-cell synchronization to global population synchronization. These qualitative agreements demonstrate that a simplified, programmable reaction-diffusion framework can capture the signalling dynamics of cardiomyocyte excitable systems, offering a new perspective for investigating signal coordination in cardiomyocyte networks.

Small vessels play a critical role in the development of various brain diseases. Significant advances have been made in high-resolution vascular imaging, but it remains a challenge to precisely segment small vessels to quantitatively assess their integrity. Existing vessel segmentation approaches typically assume, implicitly or explicitly, a tubular representation suitable for large vessels but suboptimal for small vessels because they often exhibit shape irregularity, weak contrast, and discontinuity even in high-resolution imaging data. To address these challenges, we propose a generalized and explicit small vessel representation and present a novel self-supervised small vessel segmentation network termed S3U-Net. First, S3U-Net is trained based on a novel shape-aware flux measure to estimate the direction and shape profiles of small vasculature with non-circular and irregular appearances. Second, multiple modules for local contrast attention (LCA) are incorporated to enhance small vessel responses in regions with weak contrast. Third, we develop a propagation-based post-processing algorithm based on the parallel transport frame (PTF) to enhance small vessel connectivity. To evaluate the efficacy of S3U-Net, comprehensive experiments were conducted on seven datasets from different modalities. The results demonstrated that our approach yields a considerable improvement in small vessel segmentation and their connectivity compared with existing methods. Finally, we applied S3U-Net to 7-Tesla brain images from elderly adults and demonstrate the successful detection of significant associations between small vessel density and cognitive functions.

Hepatitis caused by fowl adenovirus serotype 4 (FAdV-4) is a serious avian disease associated with huge losses to the poultry industry worldwide. Herein, we document the first outbreak of FAdV-4 infection in blue-breasted quail (Excalfactoria chinensis). The causative agent, designated as HNSQ2023, was isolated and characterized as an FAdV-4 epidemic strain using PCR amplification, DNA sequencing, and IFA staining. Comparative genomic analysis of the viral genomes of 79 virulent or non-pathogenic FAdV-4 strains showed that the gene order and shared open reading frames of HNSQ2023 were similar to those of previously reported virulent FAdV-4 strains. It also contains 100% conserved amino acid mutations in major structural proteins such as hexon and fiber-2. This is similar to the virulent FAdV-4 strains, except for an irregular mutation at aa46 (A to T) in fiber-1. Notably, the newly identified HNSQ2023 isolated from Excalfactoria chinensis and the other five epidemic FAdV-4 strains previously isolated from peacocks, chickens, ducks, and pigeons during 2018-2023 formed a close evolutionary sub-branch, distinct from the main branch, mostly composed of Chinese FAdV-4 strains originating from chickens. Furthermore, animal experiments demonstrated that HNSQ2023 retained high pathogenicity to SPF chickens and Excalfactoria chinensis, with 100% morbidity and over 90% mortality in both species. Our data shed new light on the high risk of cross-species transmission of FAdV-4 in domestic poultry and ornamental pet birds, stressing the importance of stricter biosecurity measures and necessary vaccinations for future control of this disease.

In the present study, we used the Sternberg paradigm to investigate the differences in short-term memory (STM) retrieval across different types of Chinese characters. In Experiment 1, we examined the impact of stroke count of Chinese characters on STM retrieval. The results indicated that accuracy for simple characters was higher than that for complex characters. This finding suggests that, in terms of visual-graphical characteristics, simpler characters with fewer strokes are more readily retrievable from STM. In Experiment 2, we examined the influence of the phonological features of Chinese characters on STM retrieval. The results showed that irregular characters yielded higher accuracy than regular characters. This finding implies that Chinese characters for which the pronunciation of the phonetic radical is consistent with that of the whole character (i.e., regular characters) are more difficult to retrieve from STM. In Experiment 3, we investigated the influence of the semantic features of Chinese characters on STM retrieval. The results demonstrated that accuracy for semantically non-transparent characters was higher than that for semantically transparent characters. Furthermore, across all three experiments conducted, a memory load effect was observed, indicating that the reaction times under the 7-item memory load condition were significantly longer than those under the 5-item and 3-item conditions. Overall, the results of this study indicate that the graphic, phonological, and semantic features of Chinese characters have different effects on STM retrieval. This study has provided certain insights into the language-specific mechanisms underlying STM retrieval for Chinese characters.

As the use of naturalistic data of children's language experiences increases, the temporal dynamics of the environment becomes a more apparent feature of naturalistic language. By investigating the temporal dynamics of the language environment, we can both more accurately describe the experiences of young children and connect the temporal dynamics of child-centered speech to existing experimental work showing that the temporal distribution of training has measurable effects on learning. To describe temporal patterns in children's experiences, the first step is to develop measures that quantify temporal patterns in naturalistic speech. The current work examines one such measure, the Burstiness metric, and investigates individual words' burstiness and its relationship to frequency, its behavior across different lexical classes and timescales, and whether it can be used to quantify experimental constructs of temporal orders. Using datasets of both daylong audio recordings and shortform recordings of child-centered speech, our findings show that while related, word burstiness is not an index of word frequency. Additionally, our results show that burstiness varies across words of different lexical classes and that burstiness hinges on timescale, such that words that are bursty at longer timescales are not necessarily the same ones that tend to be similarly bursty at shorter timescales. Our findings emphasize that the irregular structure of speech consequently affects how burstiness may be interpreted at different timescales and highlights how the Burstiness metric does not neatly map on to our verbal theories of temporal patterns. We discuss implications for how this measure may be used for child-centered audio and potential pitfalls.

Cyanobacterial colonies often exploit their buoyancy and large size to float upwards rapidly and form dense surface blooms, which can degrade water quality, threaten ecosystems and public health, and impose substantial economic costs. Yet, how the morphology of cyanobacterial colonies controls their vertical velocity remains poorly understood. We conducted detailed three-dimensional morphological characterization of colonies of the cyanobacterium Microcystis in lake samples at the single-colony level and performed controlled flotation experiments in a stratified fluid. Using particle tracking in a vertical density gradient, we separately quantified the contributions of colony shape and buoyant density at the level of individual colonies. Our results show that the shape factor in Stokes' law varies systematically with colony size. Consequently, the vertical velocity of colonies does not scale with the square of colony size but only with a power of 1.13, as larger colonies have a more irregular shape and therefore experience enhanced drag. We therefore correct the commonly used Stokes' law to account for the size-dependent change in the shape factor. Interestingly, implementation of this power law relationship in a vertical migration model shows widespread chaotic dynamics in the migration trajectories of Microcystis colonies. These results highlight the importance of morphological plasticity in cyanobacterial colonies and can inform predictive models and hydrodynamic control strategies for toxic blooms. Our methodology to simultaneously determine the density, shape factor and velocity is broadly applicable to suspended aggregates with complex shapes in freshwater and marine systems.

Methyleugenol microcapsules were successfully fabricated using soybean protein isolate and sodium alginate as wall materials through ultrasonic assisted microencapsulation method. A real yield of 95.45 ± 2.55% and an encapsulation efficiency of 76.95 ± 3.03% were achieved under the optimum conditions derived from Plackett-Burman and Box-Behnken designs. Physicochemical characterization confirmed effective methyleugenol encapsulation, with the microcapsules exhibiting irregular morphology, uniform particle size distribution, and distinctive wrinkled surface textures. Thermogravimetric curve indicated that the thermal stability of methyleugenol was obviously enhanced by the microencapsulation process. After microencapsulation, the antifungal activity of methyleugenol was greatly improved, with its microcapsules exhibiting comparable efficacy to nystatin against Fusarium avenaceum, demonstrating the minimum inhibitory concentration (MIC) of 0.10 mg/mL and 0.07 mg/mL, respectively. These findings provide a scientific basis for exploring the potential applications of ME microcapsules in food preservation and related industrial sectors.

Speech and music both unfold over time. However, these dynamics are perceived quite differently: music as rhythmic, and speech as quasi-rhythmic. Here, we aim to identify whether this distinction between rhythm and quasi-rhythm is sourced from the raw acoustic waveform by analyzing the modulation spectrum of the acoustic envelope. We analyzed several large corpora on three scales: the coarsest scale containing recordings of each corpus, the intermediate scale of individual speakers/songs, and the finest scale of individual sentences or short musical segments. We confirm previous findings that speech and music modulation spectra differ in their center frequency, which reflects how quickly the sound envelope fluctuates, but find that the modulation bandwidth, which captures how periodic the speech/music envelope was, is comparable for music and speech. Furthermore, the bandwidth is largely preserved across the three scales, indicating that the corpus-level temporal irregularity is dominated by the irregularity within a few seconds of speech/music recordings. These results demonstrate that the perceived rhythmicity of music may not directly reflect the temporal periodicity present in its acoustic structure.

Red blood cells (RBCs) rely on their mechanical and electrostatic properties to maintain microvascular circulation and oxygen delivery. Oxidative stress, a hallmark of many diseases, disrupts these properties by damaging membrane lipids and cytoskeletal proteins. In this study, RBCs from healthy donors were incubated with three oxidative agents, i.e., phenylhydrazine (PHZ), tert-butyl hydroperoxide (t-BHP), and diamide, to investigate how oxidative stress affects the combination of single-cell mechanical, morphological, biochemical, and electrical properties under different oxidizing conditions. All oxidants significantly increased intracellular reactive oxygen species (iROS), with PHZ producing the strongest effect. Morphological analysis revealed acanthocyte and echinocyte formation and a reduced cell diameter. Zeta potential (ζ) remained unchanged across treatments when measured in phosphate-buffered saline (PBS) solution, suggesting a preserved surface charge under these conditions. Mechanical properties were assessed by optical tweezers at the single-cell level to estimate overall elasticity and bending modulus. Untreated and t-BHP-treated RBCs showed comparable elasticity and bending modulus. Diamide increased overall elasticity and slightly elevated bending modulus, while PHZ severely impaired elongation capability, inducing an irregular trapping behavior and prohibiting the calculation of the bending modulus. These findings demonstrate that oxidative stress exerts agent-specific effects on RBC biomechanics, with t-BHP inducing mild alterations, diamide increasing elasticity, and PHZ causing profound damage. To our knowledge, this is the first study to directly correlate oxidative damage, mechanical stiffness, and electric properties across single-cell and population scales, providing a comprehensive evaluation of RBC responses to oxidative injury.

BackgroundSpinal teratomas are exceedingly rare germ cell tumors, accounting for .1%-.5% of all spinal cord tumors, with adult-onset tumors being even more uncommon. Mature teratomas consist of differentiated tissues derived from the 3 embryonic germ layers and may contain a wide variety of adult-type tissue components. Prostatic glandular tissue has been documented in only a very limited number of spinal teratoma specimens, whereas bulbourethral gland tissue has never been reported in this setting.Patient PresentationWe report a 60-year-old male patient who presented with a 7-month history of low back and right lower limb pain, which progressively worsened, along with urinary incontinence for over 3 months. Lumbar magnetic resonance imaging (MRI) revealed an irregular intraspinal space-occupying lesion at the L1 level, measuring approximately 15.0 mm × 16.6 mm × 29.4 mm, which appeared slightly hyperintense on T1-weighted imaging, heterogeneous on T2-weighted imaging, and demonstrated heterogeneous enhancement on contrast administration. The patient underwent microsurgical gross total resection of the tumor. Postoperative pathological examination showed that the tumor was composed of mature tissues derived from all 3 germ layers. Endodermal derivatives included morphologically well-formed prostatic acinar structures (positive for PSA and P504S on immunohistochemistry; the preserved basal cell layer was confirmed by 34βE12 and p63 positivity, supporting a benign prostatic origin) and bulbourethral (Cowper) gland structures (clustered mucinous acini lined by cuboidal to columnar epithelium, mucin histochemistry not performed). Mesodermal derivatives included smooth muscle bundles as well as focal thin-walled vascular spaces and scattered clusters of cells morphologically resembling adrenal zona reticularis cells (polygonal cells with abundant eosinophilic or vacuolated cytoplasm containing scant, finely granular brownish-yellow pigment consistent with lipofuscin; immunohistochemical confirmation was not available, as these cell clusters were not present on deeper sections). Ectodermal derivatives consisted of glial tissue and nerve bundles. The pathological diagnosis was mature teratoma. Postoperatively, the patient's symptoms improved markedly.ConclusionsTo our knowledge, this is the first report of bulbourethral gland differentiation in a spinal teratoma. Other rare findings in this specimen included prostatic glands, focal vascular spaces, and cell clusters resembling adrenal cortical cells. These findings further expand the known histological spectrum of spinal teratomas and suggest that during development and migration, germ cells possess the potential to differentiate into urogenital sinus derivatives and may also give rise to other mesoderm-derived lineages. Complete surgical resection remains the mainstay of treatment, and long-term imaging follow-up is essential for monitoring recurrence.

Children today experience widespread circadian disruption from nighttime screen use and irregular sleep, yet how internal clocks shape brain development is unclear. Adolescence is a critical window when synaptic connectivity is refined, in part by microglia that engulf synaptic elements. Here, in adolescent mice, we show that hippocampal microglia exhibit diurnal transcriptional rhythms, with synaptic pruning gene expression peaking during the rest phase. Inducible deletion of the core clock gene Bmal1 in microglia in early life abolishes these rhythms and alters developing hippocampal synapses in a sex-dependent manner. In males, clock disruption increases synapse engulfment, reduces dendritic spine density, and decreases synaptic connectivity; females show similar reductions in synaptic connectivity without overt postsynaptic structural changes. Microglial clock disruption also induces broad, sex-specific changes in synapse-related gene expression that overlap with neurodevelopmental disorder pathways and lead to impaired memory and sociability, indicating microglial clocks as key regulators of developmental synapse refinement.

This study reports the green synthesis of silver-titanium dioxide nanocomposites functionalized with chitosan (CS@Ag-TiO₂ NCs) using Moringa oleifera leaf extract (MOLE) as a natural reducing and stabilizing agent. The novelty of this work lies in integrating MOLE-mediated Ag-TiO₂ formation with chitosan surface functionalization to develop a bioactive nanocomposite with improved surface properties and biological performance compared with uncoated Ag-TiO₂ NCs. The synthesized nanocomposites were characterized using UV-Vis spectroscopy, FTIR, DLS, zeta potential, TEM, SEM, and EDX analyses. TEM and SEM showed irregular and predominantly spherical particles with sizes of 10-50 nm for Ag-TiO₂ NCs and 20-80 nm for CS@Ag-TiO₂ NCs. Zeta potential analysis confirmed surface charge reversal after chitosan coating, from -33.17 ± 1.46 mV for Ag-TiO₂ NCs to + 32.47 ± 3.21 mV for CS@Ag-TiO₂ NCs, supporting successful surface functionalization. CS@Ag-TiO₂ NCs showed stronger antioxidant activity than Ag-TiO₂ NCs, with IC₅₀ values of 4.27 and 6.14 µg/mL, respectively. The chitosan-functionalized nanocomposite also showed improved preliminary in vitro antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans, with inhibition zones of 17 ± 1.0, 20 ± 1.5, and 16 ± 1.0 mm, respectively. These findings suggest that MOLE-assisted green synthesis combined with chitosan functionalization is a promising strategy for developing Ag-TiO₂-based nanocomposites with enhanced antioxidant and antimicrobial potential.