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Precise identification of weeds at the maize seedling stage is pivotal for implementing Site-Specific Weed Management and minimizing herbicide environmental pollution. However, the performance of existing lightweight detectors is severely bottlenecked by unstructured field environments, characterized by the “green-on-green” spectral similarity between crops and weeds, diminutive seedling targets, and complex mutual occlusion of leaves. To address these challenges, this study proposes SLD-YOLO11, a topology-reconstructed lightweight detection model tailored for complex field environments. First, to mitigate the feature loss of tiny targets, a Lossless Downsampling Topology based on Space-to-Depth Convolution (SPD-Conv) is constructed, transforming spatial information into depth channels to preserve fine-grained features. Second, a Decomposed Large Kernel Attention (D-LKA) mechanism is designed to mimic the wide receptive field of human vision. By modeling long-range spatial dependencies with decomposed large-kernel attention, it enhances discrimination under severe occlusion by leveraging global structural context. Third, the DySample operator is introduced to replace static interpolation, enabling content-aware feature flow reconstruction. Experimental results demonstrate that SLD-YOLO11 achieves an mAP@0.5 of 97.4% on a self-collected maize field dataset, significantly outperforming YOLOv8n, YOLOv10n, YOLOv11n, and mainstream lightweight variants. Notably, the model achieves Zero Inter-class Misclassification between maize and weeds, establishing high safety standards for weeding operations. To further bridge the gap between visual perception and precision operations, a Visual Weed-Crop Competition Index (VWCI) is innovatively proposed. By integrating detection bounding boxes with species-specific morphological correction coefficients, the VWCI quantifies field weed pressure with low cost and high throughput. Regression analysis reveals a high consistency (R2 = 0.70) between the automated VWCI and manual ground-truth coverage. This study not only provides a robust detector but also offers a reliable decision-making basis for real-time variable-rate spraying by intelligent weeding robots.

Adipose-derived stem cells (ASCs) can be applied extensively in the clinic because they can be easily isolated and cause less donor-site morbidity; however, their application can be complicated by patient-specific factors, such as age and harvest site. In this study, we systematically evaluated the effects of age on the quantity and quality of human adipose-derived mesenchymal stem cells (hASCs) isolated from excised chest subcutaneous adipose tissue and investigated the underlying molecular mechanism. hASCs were isolated from donors of 3 different age-groups (i.e., child, young adult, and elderly). hASCs are available from individuals across all age-groups and maintain mesenchymal stem cell (MSC) characteristics. However, the increased age of the donors was found to have a significant negative effect on hASCs frequency base on colony-forming unit fibroblasts assay. Moreover, there is a decline in both stromal vascular fraction (SVF) cell yield and the proliferation rate of hASCs with increasing age, although this relationship is not significant. Aging increases cellular senescence, which is manifested as an increase in SA-β-gal-positive cells, increased mitochondrial-specific reactive oxygen species (ROS) production, and the expression of p21 in the elderly. Further, advancing age was found to have a significant negative effect on the adipogenic and osteogenic differentiation potentials of hASCs, particularly at the early and mid-stages of induction, suggesting a slower response to the inducing factors of hASCs from elderly donors. Finally, impaired migration ability was also observed in the elderly group and was determined to be associated with decreased expression of chemokine receptors, such as CXCR4 and CXCR7. Taken together, these results suggest that, while hASCs from different age populations are phenotypically similar, they present major differences at the functional level. When considering potential applications of hASCs in cell-based therapeutic strategies, the negative influence of age on hASC differentiation potential and migration abilities should be taken seriously.

This paper addresses the tracking control problem of the tilting quadcopter with unknown nonlinearities. A novel tilting quadcopter conception is proposed with a fully actuated version, which suggests that the translational and rotational movements can be controlled independently. Based on the Euler-Lagrange equations, the dynamics of tilting quadcopter is developed with uncertainties, where Neural Networks (NNs) are utilized to approximate the unknown nonlinearities in systems. We construct a novel auxiliary filter to obtain the estimation errors explicitly to achieve better approximation ability of NNs. By introducing new leakage terms in the adaptive scheme, the weights of identifier of NNs can converge to their optimal values. And a simple online verification is provided to test the parameter estimation convergence, which relaxes the requirement of persistent excitation condition. Moreover, we propose an Adaptive Finite-time Neural Control for the tilting quadcopter, where all the tracking errors can converge to a small neighborhood around zero in finite time as well as the estimation errors. Finally, comparative simulation results are presented to illustrate the effectiveness and superiority of our proposed control.

Background clutters and pose variation are the key factors which prevents the network from learning a robust Person re-identification (Re-ID) model. To address the problem above, we first introduce the binary segmentation mask to construct the body region served as the input of the generator, then design a segmentation mask-guided person image generation network for the pose transfer. The binary segmentation mask has the capability of removing the background clutters in pixel-level, and contains more details about the edge information, where better shape consistency can be achieved for the generated image with the input image. Compared with the previous methods, the proposed method can dramatically improve the model adaptive ability and deal with the diversity of postures. In addition, we design a lightweight attention mechanism module as a guider module, which can assist the generator to focus on the discriminative features of pedestrians. The experiment results are introduced to demonstrate the effectiveness of the proposed method and the superiority performance over most state-of-the-art methods without over-computing in the design process of the Re-ID model. It is worth mentioning that our ideas can be easily combined with other fields to solve the phenomenon of the current situation with insufficient pose variations in the datasets.

Cytotherapy is a strategy to deliver modified cells to a diseased tissue, but targeting solid tumours remains challenging. Here we design macrophages, harbouring a surface glypican-3-targeting peptide and carrying a cargo to combat solid tumours. The anchored targeting peptide facilitates tumour cell recognition by the engineered macrophages, thus enhancing specific targeting and phagocytosis of tumour cells expressing glypican-3. These macrophages carry a cargo of the TLR7/TLR8 agonist R848 and INCB024360, a selective indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor, wrapped in C16-ceramide-fused outer membrane vesicles (OMV) of Escherichia coli origin (RILO). The OMVs facilitate internalization through caveolin-mediated endocytosis, and to maintain a suitable nanostructure, C16-ceramide induces membrane invagination and exosome generation, leading to the release of cargo-packed RILOs through exosomes. RILO-loaded macrophages exert therapeutic efficacy in mice bearing H22 hepatocellular carcinomas, which express high levels of glypican-3. Overall, we lay down the proof of principle for a cytotherapeutic strategy to target solid tumours and could complement conventional treatment. Macrophages are considered a good candidate for cancer cytotherapy because of their phagocytotic capacity, enabling them to deliver cargo to tissues. Here authors engineer macrophages that are targeted to glypican-3-expressing tumour cells and equipped with drug-loaded exosomes and show therapeutic efficiency in a mouse model of hepatocellular cancer.

Individuals with anxiety exhibit high clinical usage of benzodiazepines, particularly among those with long-term use, yet the impact of these medications on cognitive function remains inconclusive. Previous research has predominantly focused on epidemiological data and metabolic measurements, often overlooking both cortical activation and the synchrony between different brain regions. This study investigates how brain neuronal activities are modulated in both long-term benzodiazepine users and nonusers during cognitive tasks, offering insights into the neural mechanisms underlying cognitive function. Fifty older adults with anxiety disorders participated in this study, including 31 long-term benzodiazepine users (BZD group) and 19 nonusers (control group). Functional near-infrared spectroscopy was used to assess cortical activation and functional connectivity during a verbal fluency task. Our study is the first to find a greater interhemispheric functional connectivity in chronic benzodiazepine users. However, no notable differences were detected between the two groups regarding behavioral performance, cortical activation, or changes in oxygenated hemoglobin concentration. Moreover, cumulative dosage of benzodiazepines use had no significant effect on dorsolateral prefrontal cortex activation. Long-term benzodiazepines use does not affect brain activation but impacts functional connectivity. The increased interhemispheric connectivity may serve to maintain the stability of brain networks, and this enhanced connectivity could be associated with the long-term adaptive disinhibition of GABAergic neurotransmission.

The stratospheric ozone layer, which prevents solar ultraviolet radiation from reaching the surface and thereby protects life on earth, is expected to recover from past depletion during this century due to the impact of the Montreal Protocol. However, how the ozone column over the Arctic will evolve over the next few decades is still under debate. In this study, we found that the ozone level in the Arctic stratosphere at 100–150 hPa during 1998–2018 exhibits a decreasing trend of − 0.12 ± 0.07 ppmv decade –1 from MERRA2, suggesting a continued depletion during this century. About 30% of this ozone depletion is contributed by the second leading mode of sea surface temperature anomalies (SSTAs) over the North Pacific with one month leading and therefore is dynamical in origin. The North Pacific SSTAs associated with this mode tend to result in a weakened Aleutian low, a strengthened Western Pacific pattern and a weakened Pacific–North American pattern, which impede the upward propagation of wavenumber-1 waves into the lower stratosphere. The changes in the stratospheric wave activity may result in decreased ozone in the Arctic lower stratosphere through weakening the Brewer-Dobson circulation. Our findings uniquely linked the recent ozone depletion in the Arctic stratosphere to the North Pacific SSTs and might provide new understanding of how dynamical processes control Arctic stratospheric ozone.

Introduction Empathy is considered the ability to understand or feel others emotions or experiences. As an important part of medical education, empathy can affect medical students in many ways. It is still lacking a comprehensive evaluation of the existing articles on empathy’s impact on medical students, despite the existence of many articles on the topic. Objectives To summarize the impact of empathy on medical students during medical education from four perspectives: mental health, academic performance, clinical competence, and specialty preference. Methods The search terms used for retrieval were “empathy”, “medical student”, “mental health”, “depression”, “anxiety”, “burnout”, “examinations”, “academic performance”, “clinical competence”, “specialty preference” on PubMed, EBSCO, and Web of Science before January 2024. The search was carried out by two reviewers. Titles and abstracts were screened independently and reviewed based on inclusion/exclusion criteria. A consensus was drawn on which articles were included. Results Our results indicated that high empathy was a positive factor for mental health, However, students with high affective empathy were more likely to suffer from depression, anxiety, and burnout. Empathy was found to be unrelated to academic performance, but positively correlated with clinical competence, particularly in terms of communication skills. Medical students with high levels of empathy tended to prefer people-oriented majors. Conclusions Medical students who score higher on the self-reported empathy scales often have better mental health, better communication skills, and tend to choose people-oriented specialties. But empathy is not related to academic performance. Additionally, the different dimensions of empathy have different impacts on medical students. It is necessary to design targeted courses and training for medical students to enhance their empathy.

Accumulation of amyloid-β (Aβ), which results in the formation of senile plaques that cause oxidative damage and neuronal cell death, has been accepted as the major pathological mechanism of Alzheimer’s disease (AD). Hence, inhibition of Aβ-induced oxidative damage and neuronal cell apoptosis represents the effective strategies in combating AD. Ginsenoside Re (Re) has pharmacological effects against Aβ-induced neurotoxicity. However, its molecular mechanism remains elusive. The present study evaluated the effect of Re against Aβ-induced cytotoxicity and apoptosis in SH-SY5Y cells, and investigated the underlying mechanism. We demonstrate that Re inhibits the Aβ-triggered mitochondrial apoptotic pathway, as indicated by maintenance of mitochondrial functional, elevated Bcl-2/Bax ratio, reduced cytochrome c release, and inactivation of caspase-3/9. Re attenuated Aβ-evoked reactive oxygen species (ROS) production, apoptosis signal-regulating kinase 1 (ASK1) phosphorylation, and JNK activation. ROS-scavenging abrogated the ability of Re to alter ASK-1 activation. Simultaneously, inhibition of JNK abolished Re-induced Bax downregulation in Aβ-challenged SH-SY5Y cells. In addition, Re enhanced activation of the nuclear factor-E2-related factor 2 (Nrf2) in Aβ-induced SH-SY5Y cells. Knockdown of Nrf2 by small interfering RNA targeting Nrf2 abolished the protective effect of Re. Our findings indicate that Re could be a potential therapeutic approach for the treatment of AD.

Inflammatory bowel disease (IBD) is closely linked to the homeostasis of the intestinal environment, and exosomes can be used to treat IBD due to their high biocompatibility and ability to be effectively absorbed by the intestinal tract. However, Ginseng-derived nanoparticles (GDNPs) have not been studied in this context and their mechanism of action remains unclear. Here, we investigated GDNPs ability to mediate intercellular communication in a complex inflammatory microenvironment in order to treat IBD. We found that GDNPs scavenge reactive oxygen species from immune cells and intestinal epithelial cells, inhibit the expression of pro-inflammatory factors, promote the proliferation and differentiation of intestinal stem cells, as well as enhancing the diversity of the intestinal flora. GDNPs significantly stabilise the intestinal barrier thereby promoting tissue repair. Overall, we proved that GDNPs can ameliorate inflammation and oxidative stress in vivo and in vitro, acting on the TLR4/MAPK and p62/Keap1/Nrf2 pathways, and exerting an anti-inflammatory and antioxidant effect. GDNPs mitigated IBD in mice by reducing inflammatory factors and improving the intestinal environment. This study offers new evidence of the potential therapeutic effects of GDNPs in the context of IBD, providing the conceptual ground for an alternative therapeutic strategy. Graphical Abstract Highlights New ideas and high compatibility of plant nanoparticle materials used in clinical medicine. Critical components and detailed mechanisms were identified through multi-omics analyses. Activation of the body's first line of defence: immune cells—anti-inflammatory pathway—TLR4/MAPK, antioxidant pathway—p62/Nrf2/Keap1 to defend against the complex inflammatory environment. Promotion of the proliferation and differentiation of intestinal stem cells by activating the Wnt/β-catenin signaling pathway, reduction of intestinal epithelial inflammation and restoration of intestinal barrier function. Regulation of the intestinal flora composition.