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Commensal bacteria generate immensely diverse active metabolites to maintain gut homeostasis, however their fundamental role in establishing an immunotolerogenic microenvironment in the intestinal tract remains obscure. Here, we demonstrate that an understudied murine commensal bacterium, Dubosiella newyorkensis , and its human homologue Clostridium innocuum , have a probiotic immunomodulatory effect on dextran sulfate sodium-induced colitis using conventional, antibiotic-treated and germ-free mouse models. We identify an important role for the D. newyorkensis in rebalancing Treg/Th17 responses and ameliorating mucosal barrier injury by producing short-chain fatty acids, especially propionate and L-Lysine (Lys). We further show that Lys induces the immune tolerance ability of dendritic cells (DCs) by enhancing Trp catabolism towards the kynurenine (Kyn) pathway through activation of the metabolic enzyme indoleamine-2,3-dioxygenase 1 (IDO1) in an aryl hydrocarbon receptor (AhR)-dependent manner. This study identifies a previously unrecognized metabolic communication by which Lys-producing commensal bacteria exert their immunoregulatory capacity to establish a Treg-mediated immunosuppressive microenvironment by activating AhR-IDO1-Kyn metabolic circuitry in DCs. This metabolic circuit represents a potential therapeutic target for the treatment of inflammatory bowel diseases. Here, Zhang et al . identify a metabolic axis by which Lys-producing commensal bacterium Dubosiella newyorkensis mediates a Treg-mediated immunosuppressive microenvironment by activating AhR-IDO1-Kyn metabolic circuitry in dendritic cells.

What are the main findings? Diffraction error is strongly correlated with the carrier-power-to-noise-density ratio (C/N0), and the C/N0 time series is consistent with the theoretically predicted growth pattern of diffraction error. This study proposes a GNSS diffraction error mitigation approach involving segmented down-weighting and elimination of affected observations. What are the implications of the main findings? C/N0 can serve as a practical indicator of diffraction-affected signals, enabling adaptive down-weighting or exclusion according to error severity. The proposed method effectively mitigates diffraction errors and substantially improves ambiguity-fixing performance and positioning accuracy in dense urban environments. In densely built urban environments, GNSS signals frequently undergo diffraction at building edges, and the resulting errors can severely degrade positioning accuracy and reliability. Previous studies have shown a strong correlation between diffraction error and the carrier-power-to-noise-density ratio (C/N0). Building on this observation, this study proposes a GNSS diffraction-mitigation method based on segmented down-weighting and exclusion of affected observations. First, an open-sky reference model of the elevation–C/N0 relationship is established for each satellite class. A robust strategy is then introduced to adaptively down-weight moderately contaminated observations and remove severely affected ones during stochastic modeling. The proposed method is evaluated using both static and kinematic datasets collected in dense urban environments. In the static experiment under severe building obstruction, the ambiguity-fixing rate (AFR) reaches 95.5%, with horizontal and vertical accuracies of 4 mm and 8 mm, respectively, substantially outperforming conventional weighting strategies. In the vehicle-based kinematic experiment, the fixed-solution rate exceeds 80%, and the float solution is also noticeably improved relative to traditional weighting and exclusion methods. Overall, the proposed method effectively mitigates diffraction-induced errors and improves positioning performance in dense urban environments, with potential applications in automated inspection, intelligent construction, and high-precision deformation monitoring.

We investigate the spatially optical solitons shedding from Airy beams and anomalous interactions of Airy beams in nonlocal nonlinear media by means of direct numerical simulations. Numerical results show that nonlocality has profound effects on the propagation dynamics of the solitons shedding from the Airy beam. It is also shown that the strong nonlocality can support periodic intensity distribution of Airy beams with opposite bending directions. Nonlocality also provides a long-range attractive force between Airy beams, leading to the formation of stable bound states of both in-phase and out-of-phase breathing Airy solitons which always repel in local media.

Background The severe postpartum hemorrhage (SPPH) leads to dangerous maternal conditions, and its rate is still increasing and the trend in related risk factors is changing. Placenta-related problems remain the high-risk factor for SPPH. The object is to investigate the prevalence and the risk factors of the severe postpartum hemorrhage in pregnant women with placenta previa or low-lying placenta. Method A retrospective analysis of pregnant women with placenta previa or low-lying placenta after 28 weeks gestation from May 2018 to May 2023 in the Peking Union Medical College Hospital was conducted. The primary outcome was severe postpartum hemorrhage defined as blood loss ≥ 1000 mL within 24 h of childbirth, or with signs or symptoms of low blood volume requiring transfusion of ≥ 4U of red blood cells. Univariate and multivariate logistic regression were used to identify potential risk factors of severe postpartum hemorrhage and receiver operating curve to evaluate the prediction performance. Results Of the 14,964 women, 201 met the inclusive criteria. SPPH rate was 1.3% overall and 18.9% in women with placenta previa or low-lying placenta. Weight (aOR = 0.93, 95%CI 0.87–0.99), increta or percreta placenta (aOR = 7.93, 95%CI 2.53–24.77) were the risk factors. The area under the ROC curve was 0.69(95%CI 0.59–0.80) for increta or percreta placenta alone, and 0.72(95%CI 0.62–0.82) for the combination of times of cesarean sections and anterior placenta. Conclusions Placenta accreta spectrum was the key independent risk factor of SPPH in women with placenta previa or low-lying placenta. Antenatal risk assessment of SPPH in these population is highly desirable and optimal intervention could be planned.

As a strategic core of the Western Land–Sea New Corridor, the Pinglu Canal Economic Belt (PCEB) is undergoing unprecedented landscape restructuring due to canal construction. This mega-project serves as a critical case for understanding how intense human intervention reshapes regional ecosystem service (ES) patterns. Integrating complex network analysis with Generalized Additive Models (GAMs), this study examines the spatiotemporal evolution of human activity intensity (HAI) and ES networks (2000–2020) and their nonlinear responses. Research findings: the PCEB’s ES network evolution reflects a “policy–terrain coupling” mechanism. While HQ remains the structural anchor for regulating services, FP drives key trade-offs. The network has transitioned from coexisting trade-offs and synergies to synergy dominance, driven by ecological engineering and spatial zoning. We identified HAI 0.10–0.15 as a critical threshold where moderate disturbance promotes service integration. However, excessive intensification leads to functional simplification. Future governance should move beyond rigid zoning, employing dynamic spatial policies and adaptive agroforestry to mitigate FP’s pressure and activate the ecological potential of transition zones. This study provides a framework for understanding nonlinear socio-ecological responses to human–policy–terrain feedback. This study provides a scientific basis for optimizing land-use management and enhancing ecosystem sustainability in the PCEB.

Acute myocardial infarction (AMI) is a major contributor to cardiovascular-related mortality, and early diagnosis is crucial for effective treatment and better outcomes. While several biomarkers have been explored for AMI, there remains a need for reliable, non-invasive biomarkers that can accurately differentiate AMI patients from healthy individuals. This study aims to identify potential mRNA biomarkers in peripheral blood that could aid in the diagnosis and monitoring of AMI. We performed transcriptomic analysis of blood samples from 81 individuals, including 16 healthy controls, 58 AMI patients, and 7 post-treated AMI individuals. Through a combination of Sparse Partial Least Squares-Discriminant Analysis (sPLS-DA), random forest (RF), Weighted Gene Co-expression Network Analysis (WGCNA), and LASSO regression, we identified mRNA markers that are significantly correlated with AMI. Specifically, the mRNA expressions of ANKRD52, ART1, NRP2, and PPP1R15A were elevated in AMI patients, whereas BAIAP2L1 and CCNE1 were downregulated. However, while these mRNA biomarkers show potential for distinguishing AMI patients from healthy individuals, further studies are needed to confirm their clinical applicability.

The gut microbiota plays a crucial role in maintaining intestinal stem cell (ISC) homeostasis and epithelial barrier integrity. Here, we report that Blautia coccoides ( B. coccoides ) is significantly reduced in inflammatory bowel disease (IBD) patients and dextran sulfate sodium (DSS)-induced colitis mice. Through an integrated approach combining RNA sequencing, metabolomic profiling, and ISC lineage tracing across multiple mucosal injury models, we demonstrate that B. coccoides colonization enhances β-hydroxybutyrate (BHB) production in intestinal epithelial cells (IECs), which activates HOPX⁺ reserve ISCs and promotes regeneration of the LGR5⁺ ISC pool, thereby accelerating epithelial repair. We further show that B. coccoides -derived indole-3-lactic acid (ILA), a tryptophan (Trp) metabolite, is converted into indole-3-propionic acid (IPA) by commensal bacteria such as P. russellii or C. sporogenes , stimulating IEC BHB synthesis. Using an engineered Escherichia coli strain expressing BC-derived phenyllactate dehydrogenase ( fldH ), we establish that both dietary Trp and bacterial fldH activity are essential for ILA/IPA generation and subsequent mucosal healing. Our findings reveal a microbiota-metabolite-ISC regulatory axis critical for epithelial regeneration and propose novel metabolite-based therapeutic strategies for IBD and other intestinal disorders associated with barrier dysfunction. Here, Zhang et al . show that the gut bacterium Blautia coccoides promotes intestinal repair by activating regenerative stem cells through indole lactic acid, providing a potential therapeutic avenue for inflammatory bowel disease.

This study investigates the spatio-temporal characteristics and driving mechanisms of ecological quality in the mountain–river–sea regional system using the Remote Sensing Ecological Index (RSEI) model, moderate-resolution imaging spectroradiometer (MODIS) data, and the Google Earth Engine (GEE) platform. The analysis, conducted at both the grid and county scales using spatial autocorrelation and geodetector, showed a notable improvement in ecological quality, with the average RSEI value rising from 0.549 in 2000 to 0.627 in 2022. The distribution pattern reveals superior quality in the northwest and inferior quality in central urban cores and coastal zones. Ecological quality exhibited significant spatial clustering, with high–high clusters in karst mountains and low–low clusters in urban and industrial zones. Geodetector analysis identified GDP and population density as dominant factors at the grid scale, and GDP and elevation at the county scale. By quantifying spatio-temporal variations and driving mechanisms of ecological quality across scales, this study provides a solid scientific foundation for regional ecological conservation and sustainable development.

Reconstructing 3D building models from point clouds acquired by UAV sensors remains challenging due to irregular building geometries and sensor noise. This paper proposes an unsupervised, geometry-oriented reconstruction method based on the line-symmetric bilateral point distribution features. The method constructs baselines from farthest point pairs within local bounding spheres, then applies dual-parameter constraints (point–line distance and point statistics on both sides of a line of symmetry) combined with density peak ranking to detect building corners without training data. Evaluations show that the method reduces Cloud-to-Mesh error by 15–20% over Polyfit, DIF method, and PolyGNN, while retaining fine details in complex L-shaped and U-shaped buildings. Reconstruction quality remains stable under 0.05 m Gaussian noise. The training-free, lightweight design enables scalable, automated 3D building reconstruction for digital-twin applications.

Background Toxoplasma gondii is a zoonotic parasite infecting approximately one-third of blood donors worldwide; hence, a better understanding of the prevalence of and associated risk factors for T. gondii infection among blood donors is necessary. This study, therefore, aimed to elucidate the infection risk in Zhejiang Province, China via cross-sectional investigation combined with a case-control design. Methods Blood samples were collected from 1807 blood donors for the cross-sectional survey between January 2023 and December 2024 in Zhejiang, eastern China. Enzyme-linked immunosorbent assay and quantitative polymerase chain reaction were used to investigate the prevalence of T. gondii. Questionnaires were used to collect demographic information. In total, 40 seropositive and 40 seronegative participants were selected for risk factor investigation. Univariate and multivariate logistic regression analyses were conducted. Results The overall prevalence of anti- T. gondii antibodies was 5.9% (95% confidence interval [CI]: 4.9–7.1%), with 100, one, and six participants found to be IgG-positive only (5.5%, 95% CI: 4.5–6.7%), IgM-positive only (0.1%, 95% CI: 0–0.4%), and IgG- and IgM-positive, respectively (0.3%, 95% CI: 0.1–0.8%). All samples were negative for T. gondii as per polymerase chain reaction test results. T. gondii seroprevalence exhibited an age-dependent increase from 2.4% (18–29 years) to 8.2% (50–59 years). Age and occupational distribution patterns varied between eastern and southern regions. Univariate analysis revealed that occupation was a risk factor for T. gondii infection. Repeated blood donation ( P  = 0.044, OR = 0.243, 95%CI: 0.061–0.964) was negatively associated with T. gondii infection. Multivariate logistic regression demonstrated that age ( P  = 0.031) and first-time donors ( P  = 0.011) were significantly associated with higher prevalence rates. Conclusion Strategies for prevention of transfusion-transmitted toxoplasmosis should be targeted to older and first-time donors. This study provides evidence-based insights to guide prevention strategies and ensure blood safety.