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ABSTRACT Herbivore grazing plays a crucial role in grassland ecosystems, yet its comprehensive impact on plant and soil nematode diversity in desert steppe remains unclear. We assessed the impact of different grazing intensities (CK: no grazing, LG: light grazing, MG: moderate grazing, HG: heavy grazing, EG: extreme heavy grazing) on plant and soil nematode diversity in desert steppe. In the HG treatment, the diversity of plants and nematodes was the lowest and significantly lower than that in the CK treatment. Compared with CK, the Sobs, Shannon‐Wiener, Inverse Simpson index, and Heip index of the plant community under HG decreased significantly by 23.78%, 37.97%, 47.43%, and 41.51%, respectively (p < 0.05). Simultaneously, the diversity indices of soil nematodes under HG also decreased significantly, being 22.2%, 40.3%, 50.9%, and 47.1% lower than those of CK, respectively. Linear and non‐linear correlation analyses demonstrated a significant positive correlation between plant diversity and nematode diversity, indicating a synergistic relationship between plant communities and soil nematode communities. Pearson correlation analysis revealed that Cleistogenes songorica (Roshev.) Ohwi and Stipa breviflora Griseb. were significantly positively correlated with the herbivorous nematode genus Paratylenchus (p < 0.05), while Convolvulus ammannii Desr. was significantly positively correlated with the genus Acrobeloides (p < 0.05). These results indicated that certain specific plant species exert significant regulatory effects on specific soil nematode species. Overall, heavy grazing is detrimental to the sustainable development of grasslands. Therefore, in light of previous research in this field, maintaining grazing intensity below the level of heavy grazing (LG or MG) is the most appropriate grassland management strategy. Herbivore grazing plays a crucial role in grassland ecosystems, yet its comprehensive impact on plant and soil nematode diversity in desert steppe remains unclear. We assessed the impact of different grazing intensities (CK: no grazing, LG: light grazing, MG: moderate grazing, HG: heavy grazing, EG: extreme heavy grazing) on plant and soil nematode diversity in desert steppe. In the HG treatment, the diversity of plants and nematodes was the lowest and significantly lower than that in the CK treatment. Compared with CK, the Sobs, Shannon‐Wiener, Inverse Simpson index, and Heip index of the plant community under HG decreased significantly by 23.78%, 37.97%, 47.43%, and 41.51%, respectively (p < 0.05). Simultaneously, the diversity indices of soil nematodes under HG also decreased significantly, being 22.2%, 40.3%, 50.9%, and 47.1% lower than those of CK, respectively. Linear and non‐linear correlation analyses demonstrated a significant positive correlation between plant diversity and nematode diversity, indicating a synergistic relationship between plant communities and soil nematode communities. Pearson correlation analysis revealed that Cleistogenes songorica (Roshev.) Ohwi and Stipa breviflora Griseb. were significantly positively correlated with the herbivorous nematode genus Paratylenchus (p < 0.05), while Convolvulus ammannii Desr. was significantly positively correlated with the genus Acrobeloides (p < 0.05). These results indicated that certain specific plant species exert significant regulatory effects on specific soil nematode species. Overall, heavy grazing is detrimental to the sustainable development of grasslands. Therefore, in light of previous research in this field, maintaining grazing intensity below the level of heavy grazing (LG or MG) is the most appropriate grassland management strategy.

The effect of grazing intensity on plant diversity has been widely studied. In this study, desert steppes with different grazing intensities (no grazing (CK), light grazing (LG), moderate grazing (MG), heavy grazing (HG), and extremely heavy grazing (EG)) in Inner Mongolia were selected to study the changes in species diversity at different spatial scales (α, β, and γ diversity) and the α diversity of different plant groups (dominant species, common species, and rare species).The results showed that the α, β, and γ diversity first decreased and then increased with increasing grazing intensity, and β diversity was observed to be the most sensitive index to the grazing intensity. Grazing had the greatest impact on the α diversity of rare species and the least impact on the α diversity of common species. Therefore, rare species are of great significance for the maintenance and assessment of biodiversity. We concluded that grazing leads to a sensitive response of β diversity, and this sensitive phenomenon is mainly affected by rare species. The results could provide scientific bases for the protection of plant diversity and sustainable grazing in desert steppes.

Background Nanjing City has a high-incidence gastric cancer (GC), but the epidemiology of gastric precancerous lesions (GPLs) remains poorly understood. This study aimed to investigate the epidemiological characteristics of Helicobacter pylori ( H. pylori ) infection, GPLs, and GCs in patients undergoing endoscopic examination in Lishui District, Nanjing. Methods This retrospective, population-based, cross-sectional study was conducted collaboratively by the Nanjing Lishui People’s Hospital and six medical community units within the county between July 2022 and June 2023. Data on biopsies and 13 C urea breath tests ( 13 C-UBT) were collected. Results A total of 15,668 individuals were included, among whom 259 had GPL (1.65%) and 218 had GC (1.39%). The H. pylori infection rate in total patients was 5014 (32.00%) (males: 2684 (34.06%); females: 2335 (29.92%)). The H. pylori infection rate is 31.45% in benign gastric lesions, 44.40% in GPLs, and 55.50% in GC, respectively. The multivariable logistic regression analysis showed that male (OR = 3.156, 95% CI: 2.865–3.376, P  < 0.001), age (OR = 1.785, 95% CI: 1.703–1.876, P  < 0.001), fresh vegetable, fruit, and white meat intake frequently (OR = 0.865, 95% CI: 0.506–2.061, P  = 0.029), high-salt diet and high-fat diet intake frequently (OR = 1.906, 95% CI: 1.101–2.932, P  = 0.014), rural residence (OR = 2.682, 95% CI: 1.010–4.754, P  = 0.040), H. pylori infection (OR = 2.022, 95% CI: 1.155–2.865, P  < 0.001) and atrophic gastritis and/or intestinal metaplasia (OR = 4.875, 95% CI: 2.229–10.663, P  < 0.001) were associated with GPLs. Male (OR = 2.021, 95% CI: 1.080–3.780, P  = 2.028), age (OR = 1.201, 95% CI: 1.174–1.238, P  < 0.001), digestive symptoms (OR = 2.256, 95% CI: 1.548–3.289, P  < 0.001), bachelor degree below (OR = 4.792, 95% CI: 3.439–6.837, P  < 0.001), farmer (OR = 1.039, 95% CI: 1.026–1.159, P  < 0.001), fresh vegetable, fruit, and white meat intake (OR = 0.231, 95% CI: 0.141–0.379, P  < 0.001), fried/barbecue/pickled food intake (OR = 6.781, 95% CI: 3.783–12.153, P < 0.001), high-salt diet and high-fat diet intake (OR = 4.374, 95% CI: 2.363–8.097, P  < 0.001), rural residence (OR = 1.230, 95% CI: 1.121–1.437, P  < 0.001), H. pylori infection (OR = 3.248, 95% CI: 2.357–4.477, P  < 0.001) and atrophic gastritis and/or intestinal metaplasia (OR = 4.875, 95% CI: 2.636–9.016, P  < 0.001) were associated with GCs. Conclusions These findings underscore the importance of implementing targeted prevention strategies and early detection programs in high-risk populations to mitigate the burden of GPLs and GCs in Nanjing.

Patient recruitment is challenging for clinical trials. We introduce TrialGPT, an end-to-end framework for zero-shot patient-to-trial matching with large language models. TrialGPT comprises three modules: it first performs large-scale filtering to retrieve candidate trials (TrialGPT-Retrieval); then predicts criterion-level patient eligibility (TrialGPT-Matching); and finally generates trial-level scores (TrialGPT-Ranking). We evaluate TrialGPT on three cohorts of 183 synthetic patients with over 75,000 trial annotations. TrialGPT-Retrieval can recall over 90% of relevant trials using less than 6% of the initial collection. Manual evaluations on 1015 patient-criterion pairs show that TrialGPT-Matching achieves an accuracy of 87.3% with faithful explanations, close to the expert performance. The TrialGPT-Ranking scores are highly correlated with human judgments and outperform the best-competing models by 43.8% in ranking and excluding trials. Furthermore, our user study reveals that TrialGPT can reduce the screening time by 42.6% in patient recruitment. Overall, these results have demonstrated promising opportunities for patient-to-trial matching with TrialGPT. Patient recruitment is challenging for clinical trials. Here, the authors introduce TrialGPT, an end-to-end framework for zero-shot patient-to-trial matching with large language models.

Precision DNA/gene replacement is a promising genome-editing tool that is highly desirable for molecular engineering and breeding by design. Although the CRISPR/Cas9 system works well as a tool for gene knockout in plants, gene replacement has rarely been reported. Towards this end, we first designed a combinatory dual-sgRNA/Cas9 vector (construct #1) that successfully deleted miRNA gene regions ( MIR169a and MIR827a ). The deletions were confirmed by PCR and subsequent sequencing, yielding deletion efficiencies of 20% and 24% on MIR169a and MIR827a loci, respectively. We designed a second structure (construct #2) that contains sites homologous to Arabidopsis TERMINAL FLOWER 1 ( TFL1 ) for homology-directed repair (HDR) with regions corresponding to the two sgRNAs on the modified construct #1. The two constructs were co-transformed into Arabidopsis plants to provide both targeted deletion and donor repair for targeted gene replacement by HDR. Four of 500 stably transformed T0 transgenic plants (0.8%) contained replaced fragments. The presence of the expected recombination sites was further confirmed by sequencing. Therefore, we successfully established a gene deletion/replacement system in stably transformed plants that can potentially be utilized to introduce genes of interest for targeted crop improvement.

Vision-based precision measurement is limited by the optical resolution. Although various super-resolution algorithms have been developed, measurement precision and accuracy are difficult to guarantee. To achieve nanoscale resolution measurement, a super-resolution microstructure concept is proposed which is based on the idea of a strong mathematical mapping relationship that may exist between microstructure surface topography features and the corresponding image pixel intensities. In this work, a series of microgrooves are ultra-precision machined and their surface topographies and images are measured. A mapping relationship model is established to analyze the effect of the microgroove surface topography on the imaging mechanism. The results show that the surface roughness and surface defects of the microgroove have significant effects on predicting the imaging mechanism. The optimized machining parameters are determined afterward. This paper demonstrates a feasible and valuable work to support the design and manufacture super-resolution microstructure which has essential applications in precision positioning measurement.

Femtosecond laser filamentation is a unique nonlinear optical phenomenon when high-power ultrafast laser propagation in all transparent optical media. During filamentation in the atmosphere, the ultrastrong field of 1013–1014 W/cm2 with a large distance ranging from meter to kilometers can effectively ionize, break, and excite the molecules and fragments, resulting in characteristic fingerprint emissions, which provide a great opportunity for investigating strong-field molecules interaction in complicated environments, especially remote sensing. Additionally, the ultrastrong intensity inside the filament can damage almost all the detectors and ignite various intricate higher order nonlinear optical effects. These extreme physical conditions and complicated phenomena make the sensing and controlling of filamentation challenging. This paper mainly focuses on recent research advances in sensing with femtosecond laser filamentation, including fundamental physics, sensing and manipulating methods, typical filament-based sensing techniques and application scenarios, opportunities, and challenges toward the filament-based remote sensing under different complicated conditions.

Cerebrovascular diseases have extreme high mortality and disability rate worldwide, and endothelial cells injury-induced atherosclerosis acts as the main cause of cerebrovascular disease. Ferroptosis is a novel type of programmed cell death depending on iron-lipid peroxidation. Recent studies have revealed that ferroptosis might promote the progression of atherosclerosis (AS). Here, this research aimed to investigate the function and its profound mechanism on vascular endothelial cells in atherosclerosis. Research results revealed that YTHDF2 expression up-regulated in ox-LDL treated human umbilical vein endothelial cells (HUVECs). Gain/loss functional assays indicated that YTHDF2 overexpression inhibited HUVECs’ proliferation and accelerated the ferroptosis in ox-LDL-administered HUVECs. Meanwhile, YTHDF2 silencing promoted cell proliferation and reduced the ferroptosis in ox-LDL-administered HUVECs. Mechanistically, in silico analysis suggested that there were potential m6A-modified sites on SLC7A11 mRNA, and YTHDF2 could bind with SLC7A11 mRNA via m6A-dependent manner. YTHDF2 promoted the degradation of SLC7A11 mRNA, thereby reducing its mRNA stability. Taken together, these findings suggest that YTHDF2 accelerates endothelial cells ferroptosis in cerebrovascular atherosclerosis, helping us enhance our comprehension on cerebrovascular disease pathological physiology.

Broken symmetries play a fundamental role in superconductivity and influence many of its properties in a profound way. Understanding these symmetry breaking states is essential to elucidate the various exotic quantum behaviors in non-trivial superconductors. Here, we report an experimental observation of spontaneous rotational symmetry breaking of superconductivity at the heterointerface of amorphous (a)-YAlO 3 /KTaO 3 (111) with a superconducting transition temperature of 1.86 K. Both the magnetoresistance and superconducting critical field in an in-plane field manifest striking twofold symmetric oscillations deep inside the superconducting state, whereas the anisotropy vanishes in the normal state, demonstrating that it is an intrinsic property of the superconducting phase. We attribute this behavior to the mixed-parity superconducting state, which is an admixture of s -wave and p -wave pairing components induced by strong spin-orbit coupling inherent to inversion symmetry breaking at the heterointerface of a-YAlO 3 /KTaO 3 . Our work suggests an unconventional nature of the underlying pairing interaction in the KTaO 3 heterointerface superconductors, and brings a new broad of perspective on understanding non-trivial superconducting properties at the artificial heterointerfaces. Superconducting interfaces involving KTaO3 have recently attracted attention due to their relatively high transition temperature. Here, the authors study amorphous-YAlO 3 /KTaO 3 interfaces and find two-fold symmetry in the superconducting regime, possibly due to a mixed-parity superconducting state.

A working model for histone H3-induced dynamic regulation of the de novo DNA methyltransferase. DNA methyltransferase autoinhibition and activation DNA methylation is established during embryogenesis by the de novo DNA methyltransferases DNMT3A and DNMT3B. Here, Yanhui Xu and colleagues determine crystal structures of DNMT3L (a catalytically inactive DNMT3 paralogue that stimulates the enzymatic activity of Dnmt3a) bound to DNMT3A and histone H3. The structure reveals an unexpected autoinhibitory conformation in the absence of histone H3, and a mechanism of H3-induced activation. DNA methylation is an important epigenetic modification that is essential for various developmental processes through regulating gene expression, genomic imprinting, and epigenetic inheritance 1 , 2 , 3 , 4 , 5 . Mammalian genomic DNA methylation is established during embryogenesis by de novo DNA methyltransferases, DNMT3A and DNMT3B 6 , 7 , 8 , and the methylation patterns vary with developmental stages and cell types 9 , 10 , 11 , 12 . DNA methyltransferase 3-like protein (DNMT3L) is a catalytically inactive paralogue of DNMT3 enzymes, which stimulates the enzymatic activity of Dnmt3a 13 . Recent studies have established a connection between DNA methylation and histone modifications, and revealed a histone-guided mechanism for the establishment of DNA methylation 14 . The ATRX–DNMT3–DNMT3L (ADD) domain of Dnmt3a recognizes unmethylated histone H3 (H3K4me0) 15 , 16 , 17 . The histone H3 tail stimulates the enzymatic activity of Dnmt3a in vitro 17 , 18 , whereas the molecular mechanism remains elusive. Here we show that DNMT3A exists in an autoinhibitory form and that the histone H3 tail stimulates its activity in a DNMT3L-independent manner. We determine the crystal structures of DNMT3A–DNMT3L (autoinhibitory form) and DNMT3A–DNMT3L-H3 (active form) complexes at 3.82 and 2.90 Å resolution, respectively. Structural and biochemical analyses indicate that the ADD domain of DNMT3A interacts with and inhibits enzymatic activity of the catalytic domain (CD) through blocking its DNA-binding affinity. Histone H3 (but not H3K4me3) disrupts ADD–CD interaction, induces a large movement of the ADD domain, and thus releases the autoinhibition of DNMT3A. The finding adds another layer of regulation of DNA methylation to ensure that the enzyme is mainly activated at proper targeting loci when unmethylated H3K4 is present, and strongly supports a negative correlation between H3K4me3 and DNA methylation across the mammalian genome 9 , 10 , 19 , 20 . Our study provides a new insight into an unexpected autoinhibition and histone H3-induced activation of the de novo DNA methyltransferase after its initial genomic positioning.