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Whether it is the Summer Olympics or the Winter Olympics, in order to resolve potential sports disputes, the Court of Arbitration for Sport (CAS) sets up a special ad hoc tribunal in the host city of the Olympic Games. Although CAS ad hoc rules have many similarities with ordinary procedures, they are different in terms of the legal basis, legal remedies, and certain procedural rules. During the Beijing 2022 Winter Olympics (Beijing 2022), the CAS Ad Hoc Division and the CAS Anti-Doping Division heard a total of seven cases. These cases involve issues such as provisional suspension of games, protection of minors, unreasonable delays in test results, cancellation of award ceremonies, and the timing of disputes. the CAS Ad Hoc Division decisions on the above issues can be regarded as the latest developments in the application of international sports arbitration rules.

Retinal structure and function have been studied in many vertebrate orders, but molecular characterization has been largely confined to mammals. We used single-cell RNA sequencing (scRNA-seq) to generate a cell atlas of the chick retina. We identified 136 cell types plus 14 positional or developmental intermediates distributed among the six classes conserved across vertebrates – photoreceptor, horizontal, bipolar, amacrine, retinal ganglion, and glial cells. To assess morphology of molecularly defined types, we adapted a method for CRISPR-based integration of reporters into selectively expressed genes. For Müller glia, we found that transcriptionally distinct cells were regionally localized along the anterior-posterior, dorsal-ventral, and central-peripheral retinal axes. We also identified immature photoreceptor, horizontal cell, and oligodendrocyte types that persist into late embryonic stages. Finally, we analyzed relationships among chick, mouse, and primate retinal cell classes and types. Our results provide a foundation for anatomical, physiological, evolutionary, and developmental studies of the avian visual system. The evolutionary relationships of organisms and of genes have long been studied in various ways, including genome sequencing. More recently, the evolutionary relationships among the different types of cells that perform distinct roles in an organism, have become a subject of inquiry. High throughput single-cell RNA sequencing is a technique that allows scientists to determine what genes are switched on in single cells. This technique makes it possible to catalogue the cell types that make up a tissue and generate an atlas of the tissue based on what genes are switched on in each cell. The atlases can then be compared among species. The retina is a light-sensitive tissue that animals with a backbone, called vertebrates, use to see. The basic plan of the retina is very similar in vertebrates: five classes of neurons – the cells that make up the nervous system – are arranged into three layers. The chicken is a highly visual animal and it has frequently been used to study the development of the retina, from understanding how unspecialized embryonic cells become neurons to examining how circuits of neurons form. The structure and role of the retina have been studied in many vertebrates, but detailed descriptions of this tissue at the molecular level have been largely limited to mammals. To bridge this gap, Yamagata, Yan and Sanes generated the first cell atlas of the chicken retina. Additionally, they developed a gene editing-based technique based on CRISPR technology called eCHIKIN to label different cell types based on genes each type switched on selectively, providing a means of matching their shape and location to their molecular identity. Using these methods, it was possible to subdivide each of the five classes of neurons in the retina into multiple distinct types for a total of 136. The atlas provided a foundation for evolutionary analysis of how retinas evolve to serve the very different visual needs of different species. The chicken cell types could be compared to types previously identified in similar studies of mouse and primate retinas. Comparing the relationships among retinal cells in chickens, mice and primates revealed strong similarities in the overall cell classes represented. However, the results also showed big differences among species in the specific types within each class, and the genes that were switched on within each cell type. These findings may provide a foundation to study the anatomy, physiology, evolution, and development of the avian visual system. Until now, neural development of the chicken retina was being studied without comprehensive knowledge of its cell types or the developmentally important genes they express. The system developed by Yamagata, Yan and Sanes may be used in the future to learn more about vision and to investigate how neural cell types evolve to match the repertoire of each species to its environment.

Within 40 min, hexagonal boron nitride (h-BN) was rapidly synthesized via microwave heating without using catalyst and protective gas. Melamine and boric acid were used as raw materials, and carbon fiber was utilized as microwave absorber, respectively. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM) were used to characterize the structures and morphologies of the samples. Results indicated that the whisker-like h-BN with diameters of 200–500 nm and lengths of 15–25 μm were successfully obtained. The specific surface area of the product was 510.941 m2 g−1. The maximum adsorption capacity for methylene blue solution of the as-obtained h-BN was high up to ~ 230 mg g−1 at room temperature. The excellent adsorption performance of the samples may be attributed to the oxygen-containing functional groups and defects formed during the high-energy microwave irradiation.

Most irreversible blindness results from retinal disease. To advance our understanding of the etiology of blinding diseases, we used single-cell RNA-sequencing (scRNA-seq) to analyze the transcriptomes of ~85,000 cells from the fovea and peripheral retina of seven adult human donors. Utilizing computational methods, we identified 58 cell types within 6 classes: photoreceptor, horizontal, bipolar, amacrine, retinal ganglion and non-neuronal cells. Nearly all types are shared between the two retinal regions, but there are notable differences in gene expression and proportions between foveal and peripheral cohorts of shared types. We then used the human retinal atlas to map expression of 636 genes implicated as causes of or risk factors for blinding diseases. Many are expressed in striking cell class-, type-, or region-specific patterns. Finally, we compared gene expression signatures of cell types between human and the cynomolgus macaque monkey, Macaca fascicularis . We show that over 90% of human types correspond transcriptomically to those previously identified in macaque, and that expression of disease-related genes is largely conserved between the two species. These results validate the use of the macaque for modeling blinding disease, and provide a foundation for investigating molecular mechanisms underlying visual processing.

In situ tuning of the electronic structure of active sites is a long-standing challenge. Herein, we propose a strategy by controlling the hydrogen spillover distance to in situ tune the electronic structure. The strategy is demonstrated to be feasible with the assistance of CoO x /Al 2 O 3 /Pt catalysts prepared by atomic layer deposition in which CoO x and Pt nanoparticles are separated by hollow Al 2 O 3 nanotubes. The strength of hydrogen spillover from Pt to CoO x can be precisely tailored by varying the Al 2 O 3 thickness. Using CoO x /Al 2 O 3 catalyzed styrene epoxidation as an example, the CoO x /Al 2 O 3 /Pt with 7 nm Al 2 O 3 layer exhibits greatly enhanced selectivity (from 74.3% to 94.8%) when H 2 is added. The enhanced selectivity is attributed to the introduction of controllable hydrogen spillover, resulting in the reduction of CoO x during the reaction. Our method is also effective for the epoxidation of styrene derivatives. We anticipate this method is a general strategy for other reactions. In situ tuning of the electronic structure of active sites is a long-standing challenge. Here, the authors report an approach to tune the electronic structure of cobalt species during the styrene epoxidation reaction by the introduction of controllable hydrogen spillover for enhanced selectivity.

Grain boundary controlling is an effective approach for manipulating the electronic structure of electrocatalysts to improve their hydrogen evolution reaction performance. However, probing the direct effect of grain boundaries as highly active catalytic hot spots is very challenging. Herein, we demonstrate a general water-assisted carbothermal reaction strategy for the construction of ultrathin Mo 2 C nanosheets with high-density grain boundaries supported on N-doped graphene. The polycrystalline Mo 2 C nanosheets are connected with N-doped graphene through Mo–C bonds, which affords an ultra-high density of active sites, giving excellent hydrogen evolution activity and superior electrocatalytic stability. Theoretical calculations reveal that the d z 2 orbital energy level of Mo atoms is controlled by the MoC 3 pyramid configuration, which plays a vital role in governing the hydrogen evolution activity. The d z 2 orbital energy level of metal atoms exhibits an intrinsic relationship with the catalyst activity and is regarded as a descriptor for predicting the hydrogen evolution activity. Probing the direct effect of grain boundaries as active catalytic sites is very challenging. Here, the authors reveal that the d z 2 orbital energy level of Mo atoms in grain boundaries exhibits an intrinsic relationship with the hydrogen evolution activity.

Postoperative nausea and vomiting (PONV) represent significant concerns for patients undergoing surgical procedures, as these symptoms greatly impact their postoperative experience. Among female patients undergoing laparoscopic surgery, the incidence of PONV is estimated to be approximately 45%. Moreover, for those individuals who have not undergone preventive treatment, the risk of experiencing PONV can be as high as 80%.Regrettably, despite ongoing efforts, there is still a lack of a fully effective and comprehensive solution to effectively manage and prevent PONV in these patient populations. The pursuit of an ideal strategy for the prevention and management of PONV remains an active area of research and clinical investigation. This prospective, single-center, randomized, double-blind study was conducted at Gansu Provincial Hospital from June 2021 to March 2022, involving a cohort of 100 subjects aged 18–65 years undergoing non-emergent gynaecological laparoscopic surgery. Prior to anesthesia induction, subjects were intravenously administered either 6.25 mg of promethazine or 1 mL of saline. Postoperatively, all subjects received patient-controlled intravenous analgesia and a continuous infusion of metoclopramide at a rate of 50 mg. The primary outcome measures included assessing the incidence of postoperative nausea and vomiting at 72 h following the surgical procedure. The results of this study show that the overall incidence of postoperative nausea and vomiting within 72 h after operation is significantly different between the two groups before. ( P  = 0.026, P  = 0.012). The incidence and severity of nausea during the early period (the first 6 h postoperatively) was significantly different between groups ( P  = 0.043, 95%CI(-0.273,-0.019), P  = 0.048). A statistically significant difference was found in the incidence and severity within 24 h postoperatively ( P  = 0.026,95%CI (-0.348,-0.042), P  = 0.003). Vomiting incidence and severity were lower than in the control group at the 6 h postoperatively but without statistical difference between the two groups ( P  = 0.166, 95%CI(-0.164,0.016) P  = 0.180). Vomiting incidence and severity were statistically different during the 24 h postoperatively ( P  = 0.011, 95%CI(-0.342,-0.048), P  = 0.004). A significant statistical difference was found in the satisfaction between the two groups during the postoperative observation period ( P  = 0.002). The administration of preoperative prophylactic promethazine proved to be notably effective in diminishing both the incidence and severity of postoperative nausea and vomiting within the initial 72 h postoperatively. This intervention demonstrated a favorable safety profile, characterized by a minimal occurrence of adverse effects and an absence of serious adverse reactions. Furthermore, the satisfaction levels of patients undergoing this prophylactic approach were observed to be improved. These findings highlight the potential benefits of preoperative prophylactic promethazine in enhancing the postoperative experience for patients, with positive implications for their overall satisfaction with the surgical procedure.  Clinical Trials Registration Number : (18/12/2021) ChiCTR2100054495.

The basic plan of the retina is conserved across vertebrates, yet species differ profoundly in their visual needs 1 . Retinal cell types may have evolved to accommodate these varied needs, but this has not been systematically studied. Here we generated and integrated single-cell transcriptomic atlases of the retina from 17 species: humans, two non-human primates, four rodents, three ungulates, opossum, ferret, tree shrew, a bird, a reptile, a teleost fish and a lamprey. We found high molecular conservation of the six retinal cell classes (photoreceptors, horizontal cells, bipolar cells, amacrine cells, retinal ganglion cells (RGCs) and Müller glia), with transcriptomic variation across species related to evolutionary distance. Major subclasses were also conserved, whereas variation among cell types within classes or subclasses was more pronounced. However, an integrative analysis revealed that numerous cell types are shared across species, based on conserved gene expression programmes that are likely to trace back to an early ancestral vertebrate. The degree of variation among cell types increased from the outer retina (photoreceptors) to the inner retina (RGCs), suggesting that evolution acts preferentially to shape the retinal output. Finally, we identified rodent orthologues of midget RGCs, which comprise more than 80% of RGCs in the human retina, subserve high-acuity vision, and were previously believed to be restricted to primates 2 . By contrast, the mouse orthologues have large receptive fields and comprise around 2% of mouse RGCs. Projections of both primate and mouse orthologous types are overrepresented in the thalamus, which supplies the primary visual cortex. We suggest that midget RGCs are not primate innovations, but are descendants of evolutionarily ancient types that decreased in size and increased in number as primates evolved, thereby facilitating high visual acuity and increased cortical processing of visual information. Single-cell and single-nucleus transcriptomic analysis of retina from 17 vertebrate species shows high conservation of retinal cell types and suggests that midget retinal ganglion cells in primates evolved from orthologous cells in ancestral mammals.

Failures in solar photovoltaic (PV) modules generate heat, leading to various hotspots observable in infrared images. Automated hotspot detection technology enables rapid fault identification in PV systems, while PV array detection, leveraging geometric cues from infrared images, facilitates the precise localization of defects. This study tackles the complexities of detecting PV array regions and diverse hotspot defects in infrared imaging, particularly under the conditions of complex backgrounds, varied rotation angles, and the small scale of defects. The proposed model encodes infrared images to extract semantic features, which are then processed through an PV array detection branch and a hotspot detection branch. The array branch employs a diffusion-based anchor-free mechanism with rotated bounding box regression, enabling the robust detection of arrays with diverse rotational angles and irregular layouts. The defect branch incorporates a novel inside-awareness loss function designed to enhance the detection of small-scale objects. By explicitly modeling the dependency distribution between arrays and defects, this loss function effectively reduces false positives in hotspot detection. Experimental validation on a comprehensive PV dataset demonstrates the superiority of the proposed method, achieving a mean average precision (mAP) of 71.64% for hotspot detection and 97.73% for PV array detection.

In aerospace and new-energy vehicle manufacturing, there is an increasing demand for the high-quality joining of large, curved aluminum alloy structures. This study presents a robotic friction stir welding (RFSW) system employing a force/position hybrid control. An eight-axis linkage platform integrates an electric spindle, multidimensional force sensors, and a laser displacement sensor, ensuring trajectory coordination between the robot and the positioner. By combining long-range constant displacement with small-range constant pressure—supplemented by an adaptive transition algorithm—the system regulates the axial stirring depth and downward force. The experimental results confirm that this approach effectively compensates for robotic flexibility, keeping weld depth and pressure deviations within 5%, significantly improving seam quality. Further welding verification was performed on typical curved panels for aerospace applications, and the results demonstrated strong adaptability under high-load, multi-DOF conditions, without crack formation. This research could advance the field toward more robust, automated, and adaptive RFSW solutions for aerospace, automotive, and other high-end manufacturing applications.