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Background Numerous animal species employ seasonal breeding strategies to cope with the challenges posed by environmental stress. Males exhibit periodic testicular development and spermatogenesis, which involves complex gene regulation and various cellular response mechanisms. However, the differences among species largely constrain our comprehensive understanding of this ecological adaptation phenomenon. Here, we explored the regulatory mechanism of seasonal testicular regression in plateau zokor ( Eospalax baileyi ), a typical seasonal breeding animal, through natural population survey and laboratory verification. Results In natural populations, testicular regression was accompanied by reduction in androgen secretion and glutathione (GSH) concentration and the downregulated of GSH peroxidase 4 ( Gpx4 ) gene, suggesting that androgen may induce ferroptosis to participate in the breeding regulation of plateau zokor. To this end, we carried out an indoor control experiment to deprive animals of androgen signals during the breeding season, and observed gonadal regression, abnormal spermatogenesis, and hormone level disorders. RNA-Seq analysis revealed, the induction of the expression of 658 genes in the testis of zokor in response to the regulation of androgen signaling. These differentially expressed genes were enriched in response to oxidative stress, GSH metabolism, and ferroptosis. By measuring GSH concentration and observing the downregulation of Gpx4 , we confirmed that androgen is a regulatory factor that induces ferroptosis in the testis of plateau zokor. Conclusions Overall, we reported, for the first time, the role of ferroptosis in the regulation of seasonal breeding, providing a reference for understanding the regulatory mechanism underlying the seasonal breeding strategies of animals.

A virtual reality movie is a kind of movie that is planned, shot and produced using virtual reality technology and viewed by the audience using virtual reality devices. This paper proposes using a 3D virtual camera to improve the shooting of virtual reality movies on screens. The camera focal length is utilized to regulate the size of the scene view body, and the adaptive Kalman filter method is employed to compensate for the camera’s attitude data. Select the most commonly used optical motion capture technology for virtual reality movies, build a motion capture system model, screen the optical motion capture data, and introduce the decision tree learning method in machine learning to analyze the correct rate of virtual motion recognition matching. Collect the research data, analyze the gender significance difference of the researched people by using the independent sample test, and share the immersion effect of virtual reality movie works by combining the four-dimensional experience of the researched people’s sensory, interaction, ease of use, and emotion. The virtual reality movie works have good performance in the four aspects of user sensory experience, interaction experience, ease of use experience and emotional experience, among which the mean value of sensory experience is 4.3426, which is the most outstanding, indicating that the virtual reality movie that integrates 3D image generation technology, live preview technology and performance capture technology has strong immersive creation ability.

The three-dimensional (3-D) transition of the leading-edge vortex (LEV) and the force characteristics of the plunging airfoil are investigated in the chord-based Strouhal number $St_c$ range of 0.10 to 1.0 by means of experimental measurements, numerical simulations and linear stability analysis in order to understand the spanwise instabilities and the effects on the force. We find that the interaction pattern of the LEV, the LEV from a previous cycle (pLEV) and the trailing-edge vortex (TEV) is the primary mechanism that affects the 3-D transition and associated force characteristics. For $St_c \\leq 0.16$, the 3-D transition is dominated by the LEV–TEV interaction. For $0.16 < St_c \\leq 0.44$, the TEV lies in the middle of the LEV and the pLEV and therefore vortex interaction between them is relatively weak; as a result, the LEV remains two-dimensional up to a relatively high Reynolds number of $Re = 4000$ at $St_c = 0.32$. For $0.44 < St_{c} \\leq 0.54$, and at relatively low Reynolds numbers, the pLEV and the TEV tend to form a clockwise vortex pair, which is beneficial for the high lift and stability of the LEV. For $0.49 \\leq St_c$, the pLEV and TEV tend to form an anticlockwise vortex pair, which is detrimental to the lift and flow stability. In the last $St_c$ range, vortex interaction involving the LEV, the TEV and the pLEV results in an unstable period-doubling mode which has a wavelength of about two chord-lengths and the 3-D transition enhances the lift.

Background Introgression has repeatedly been shown to play an important role in the adaptation of species to extreme environments, yet how introgression enables rodents with specialized subterranean lifestyle to acclimatize to high altitudes is still unclear. Myospalacinae is a group of subterranean rodents, among which the high-altitude plateau zokors ( Eospalax baileyi ) and the low-altitude Gansu zokors ( E. cansus ) are sympatrically distributed in the grassland ecosystems of the Qinghai-Tibet Plateau (QTP). Together, they provide a model for the study of the role of introgression in the adaptation of low-altitude subterranean rodents to high altitudes. Results Applying low-coverage whole-genome resequencing and population genetics analyses, we identified evidence of adaptive introgression from plateau zokors into Gansu zokors, which likely facilitated the adaptation of the latter to the high-altitude environment of the QTP. We identified positively selected genes with functions related to energy metabolism, cardiovascular system development, calcium ion transport, and response to hypoxia which likely made critical contributions to adaptation to the plateau environment in both plateau zokors and high-altitude populations of Gansu zokors. Conclusions Introgression of genes associated with hypoxia adaptation from plateau zokors may have played a role in the adaptation of Gansu zokors to the plateau environment. Our study provides new insights into the understanding of adaptive evolution of species on the QTP and the importance of introgression in the adaptation of species to high-altitude environments.

Recording the trajectory of table tennis balls in real-time enables the analysis of the opponent’s attacking characteristics and weaknesses. The current analysis of the ball paths mainly relied on human viewing, which lacked certain theoretical data support. In order to solve the problem of the lack of objective data analysis in the research of table tennis competition, a target detection algorithm-based table tennis trajectory extraction network was proposed to record the trajectory of the table tennis movement in video. The network improved the feature reuse rate in order to achieve a lightweight network and enhance the detection accuracy. The core of the network was the “feature store & return” module, which could store the output of the current network layer and pass the features to the input of the network layer at the next moment to achieve efficient reuse of the features. In this module, the Transformer model was used to secondarily process the features, build the global association information, and enhance the feature richness of the feature map. According to the designed experiments, the detection accuracy of the network was 96.8% for table tennis and 89.1% for target localization. Moreover, the parameter size of the model was only 7.68 MB, and the detection frame rate could reach 634.19 FPS using the hardware for the tests. In summary, the network designed in this paper has the characteristics of both lightweight and high precision in table tennis detection, and the performance of the proposed model significantly outperforms that of the existing models.

Despite the rapid progress of organic solar cells based on non-fullerene acceptors, simultaneously achieving high power conversion efficiency and long-term stability for commercialization requires sustainable research effort. Here, we demonstrate stable devices by integrating a wide bandgap electron-donating polymer (namely PTzBI-dF) and two acceptors (namely L8BO and Y6) that feature similar structures yet different thermal and morphological properties. The organic solar cell based on PTzBI-dF:L8BO:Y6 could achieve a promising efficiency of 18.26% in the conventional device structure. In the inverted structure, excellent long-term thermal stability over 1400 h under 85 °C continuous heating is obtained. The improved performance can be ascribed to suppressed charge recombination along with appropriate charge transport. We find that the morphological features in terms of crystalline coherence length of fresh and aged films can be gradually regulated by the weight ratio of L8BO:Y6. Additionally, the occurrence of melting point decrease and reduced enthalpy in PTzBI-dF:L8BO:Y6 films could prohibit the amorphous phase to cluster, and consequently overcome the energetic traps accumulation aroused by thermal stress, which is a critical issue in high efficiency non-fullerene acceptors-based devices. This work provides insight into understanding non-fullerene acceptors-based organic solar cells for improved efficiency and stability. Energetic traps accumulation aroused by thermal stress is a critical issue in organic solar cells. Here, authors integrate a wide bandgap polymer and two non-fullerene acceptors with different thermal and morphological properties, realizing a promising efficiency of 18.26% and long device stability.

To address the challenges associated with supervising workers who wear safety belts while working at heights, this study proposes a solution involving the utilization of an object detection model to replace manual supervision. A novel object detection model, named ESE-YOLOv8, is introduced. The integration of the Efficient Multi-Scale Attention (EMA) mechanism within this model enhances information entropy through cross-channel interaction and encodes spatial information into the channels, thereby enabling the model to obtain rich and significant information during feature extraction. By employing GSConv to reconstruct the neck into a slim-neck configuration, the computational load of the neck is reduced without the loss of information entropy, allowing the attention mechanism to function more effectively, thereby improving accuracy. During the model training phase, a regression loss function named the Efficient Intersection over Union (EIoU) is employed to further refine the model’s object localization capabilities. Experimental results demonstrate that the ESE-YOLOv8 model achieves an average precision of 92.7% at an IoU threshold of 50% and an average precision of 75.7% within the IoU threshold range of 50% to 95%. These results surpass the performance of the baseline model, the widely utilized YOLOv5 and demonstrate competitiveness among state-of-the-art models. Ablation experiments further confirm the effectiveness of the model’s enhancements.

The performance of organic photovoltaics is largely dependent on the balance of short-circuit current density (J SC ) and open-circuit voltage (V OC ). For instance, the reduction of the active materials’ optical bandgap, which increases the J SC , would inevitably lead to a concomitant reduction in V OC . Here, we demonstrate that careful tuning of the chemical structure of photoactive materials can enhance both J SC and V OC simultaneously. Non-fullerene organic photovoltaics based on a well-matched materials combination exhibit a certified high power conversion efficiency of 12.25% on a device area of 1 cm 2 . By combining Fourier-transform photocurrent spectroscopy and electroluminescence, we show the existence of a low but non-negligible charge transfer state as the possible origin of V OC loss. This study highlights that the reduction of the bandgap to improve the efficiency requires a careful materials design to minimize non-radiative V OC losses. Materials design rules play a key role in enabling high performance in organic photovoltaics. Here the authors achieve 12.25% efficiency on 1 cm 2 non-fullerene solar cells by tuning the side chains’ branching point and the fluorine substitutions in donor and acceptor materials.

The growing global burden of visual impairment necessitates better population eye screening for early detection of eye diseases. However, accessibility to testing is often limited and centralized at in-hospital settings. Furthermore, many eye screening programs were disrupted by the COVID-19 pandemic, presenting an urgent need for out-of-hospital solutions. This study investigates the performance of a novel remote perimetry application designed in a virtual reality metaverse environment to enable functional testing in community-based and primary care settings. This was a prospective observational study investigating the performance of a novel remote perimetry solution in comparison with the gold standard Humphrey visual field (HVF) perimeter. Subjects received a comprehensive ophthalmologic assessment, HVF perimetry, and remote perimetry testing. The primary outcome measure was the agreement in the classification of overall perimetry result normality by the HVF (Swedish interactive threshold algorithm–fast) and testing with the novel algorithm. Secondary outcome measures included concordance of individual testing points and perimetry topographic maps. We recruited 10 subjects with an average age of 59.6 (range 28-81) years. Of these, 7 (70%) were male and 3 (30%) were female. The agreement in the classification of overall perimetry results was high (9/10, 90%). The pointwise concordance in the automated classification of individual test points was 83.3% (8.2%; range 75%-100%). In addition, there was good perimetry topographic concordance with the HVF in all subjects. Remote perimetry in a metaverse environment had good concordance with gold standard perimetry using the HVF and could potentially avail functional eye screening in out-of-hospital settings.