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The limited signal of long-wavelength near-infrared-II (NIR-II, 900–1880 nm) fluorophores and the strong background caused by the diffused photons make high-contrast fluorescence imaging in vivo with deep tissue disturbed still challenging. Here, we develop NIR-II fluorescent small molecules with aggregation-induced emission properties, high brightness, and maximal emission beyond 1200 nm by enhancing electron-donating ability and reducing the donor-acceptor (D-A) distance, to complement the scarce bright long-wavelength emissive organic dyes. The convincing single-crystal evidence of D-A-D molecular structure reveals the strong inhibition of the π-π stacking with ultralong molecular packing distance exceeding 8 Å. The delicately-designed nanofluorophores with bright fluorescent signals extending to 1900 nm match the background-suppressed imaging window, enabling the signal-to-background ratio of the tissue image to reach over 100 with the tissue thickness of ~4–6 mm. In addition, the intraluminal lesions with strong negatively stained can be identified with almost zero background. This method can provide new avenues for future long-wavelength NIR-II molecular design and biomedical imaging of deep and highly scattering tissues. To achieve high-contrast in fluorescence imaging of deep tissues is challenging. Here, the authors develop NIR-II fluorescent small molecules with high brightness and emission extending to 1900 nm, enabling in vivo imaging of deep tissues with enhanced signal-to-background ratios.

In vivo fluorescence imaging in the second near-infrared window (NIR-II) has been considered as a promising technique for visualizing mammals. However, the definition of the NIR-II region and the mechanism accounting for the excellent performance still need to be perfected. Herein, we simulate the photon propagation in the NIR region (to 2340 nm), confirm the positive contribution of moderate light absorption by water in intravital imaging and perfect the NIR-II window as 900–1880 nm, where 1400–1500 and 1700–1880 nm are defined as NIR-IIx and NIR-IIc regions, respectively. Moreover, 2080–2340 nm is newly proposed as the third near-infrared (NIR-III) window, which is believed to provide the best imaging quality. The wide-field fluorescence microscopy in the brain is performed around the NIR-IIx region, with excellent optical sectioning strength and the largest imaging depth of intravital NIR-II fluorescence microscopy to date. We also propose 1400 nm long-pass detection in off-peak NIR-II imaging whose performance exceeds that of NIR-IIb imaging, using bright fluorophores with short emission wavelength.Moderate light absorption by bio-tissue is conducive to the imaging performance. The second near-infrared window is perfected as 900–1880 nm, and 2080–2340 nm is proposed as the third near-infrared window.

In view of the current severe situation of illegal land use in China, it is of great significance to explore the impact of the evolution and promotion of land law enforcement effectiveness, which will improve China’s land law enforcement system and effectively curb illegal land use. This paper explains the changes and enhancements of the effectiveness of land law enforcement since the implementation of China’s National Land Supervision System in terms of the deterrence, difficulty, and strength of land law enforcement, and explores the role of land law enforcement effectiveness in changing illegal land use behaviors from a theoretical level. Then, a corresponding empirical test was carried out using the provincial panel data of Mainland China from 2007 to 2016. The results show that the increase in land law enforcement deterrence and strength will help reduce the number of illegal land use cases, but it will drive the lawbreakers to \"commit major cases in desperation\", leading to the increase of the degree of illegal land use; and with the decrease of land law enforcement difficulty, the degree of illegal land use will be significantly reduced. At the end of this paper, several policy suggestions are put forward to effectively curb the illegal land use from the perspective of improving the land law enforcement system and enhancing the effectiveness of law enforcement.

•Hippocampus encodes spatial context in visual search tasks.•Anterior hippocampus stores context–target relations.•Posterior hippocampus holds sole-context configurations.•TPJ adjusts prioritization based on predictivity of learned configural cues.•Distinct hippocampal signals guide attentional target selection. Humans can learn to exploit repeated distractor arrangements to optimize attentional selection of targets, producing contextual facilitation. The hippocampus is thought to support context representations acquired from repeatedly searching a given scene layout. However, it remains unclear whether the hippocampus primarily encodes context–target associations, in which the distractor layout directly predicts the target location, or whether it additionally encodes associations among distractors, enabling target prioritization indirectly via context suppression. To examine the neural mechanisms of contextual learning, we combined functional magnetic resonance imaging with a two-phase visual search paradigm: Phase 1 presented predictive (repeated) distractor layouts with consistent target locations, affording contextual cueing; Phase 2 rendered these layouts non-predictive by randomizing target locations, fostering context suppression. Contextual facilitation was compared against a baseline of non-repeated arrangements. We found that both context–target (Phase 1) and distractor–distractor (Phase 2) associations were reliably decoded from the hippocampus using correlation-based multi-voxel pattern analysis. A functional dissociation emerged along the hippocampal axis: anterior and posterior hippocampal regions identified in the whole-brain univariate analyses exhibited relatively greater contributions to Phase 1 context-target and Phase 2 distractor–distractor associations, respectively, indicating their stronger involvement in the corresponding memory representations. Connectivity modeling showed the temporoparietal junction (TPJ) interacted with the hippocampus in different ways depending on context predictivity. These findings indicate anatomically separable hippocampal circuits represent predictive context–target and non-predictive distractor–distractor relations, with their attentional effects gated by the TPJ. Although the hippocampus supports the encoding and retrieval of recurrent spatial distractor-target relations in visual search, its distinct roles in representing context-target relations (associating the target location with the configuration of distractors) versus sole-context (distractor-distractor) configurations has not been dissociated. The present study decoded both forms of contextual representation in the hippocampus: the anterior hippocampus preferentially encoded context-target associations, whereas the posterior hippocampus maintained sole-context memory. The signals generated by these distinct hippocampal regions regulate how the target is prioritized for attentional selection, with the temporoparietal junction (TPJ) dynamically adjusting the mode of prioritization in response to the learnt configural structure and how reliably it predicts the target location.

Pollution-induced flashover is one of the most serious power accidents, and the pollution degree of insulators depends on atmospheric environmental parameters. The pollution models used in the power system research are usually static, but the environmental parameters are dynamic. Therefore, the study on the dynamic pollution prediction model is of great importance. In this paper, the dynamic pollution prediction model of insulators based on atmospheric environmental parameters was built, and insulators’ structure coefficients were proposed based on the model. Firstly, the insulator dynamic pollution model based on meteorological data (PM2.5, PM10, TSP (total suspended particulate), and wind speed) was proposed, and natural pollution tests were also conducted as verification tests. Furthermore, insulator structure coefficients c1, c2 (c1: pollution ratio of U210BP/170 to XP-160; c2: calculated pollution ratio of U210BP/170T to XP-160) were then obtained, and their influence factors were discussed. At last, insulator structure coefficients were calculated, and it can be seen that the calculated error of insulator structure coefficients was acceptable, with the average re (relative errors) at 9.0% (c1) and 13.5% (c2), which verifies the feasibility of the model. Based on the results in this paper, the NSDD (non-soluble deposit density) of insulators with different structures can be obtained using the insulators’ structure coefficient and the reference XP-160 insulator’s NSDD.

Male infertility, a significant global public health challenge, arises from multifactorial interactions involving genetic, metabolic, and psychological factors. While psychological stress (depression/anxiety/stress, DAS) is increasingly linked to impaired sperm quality, its molecular mechanisms remain unclear. This cross-sectional study investigates mitochondrial metabolic reprogramming via the pyruvate dehydrogenase kinase (PDK)-pyruvate dehydrogenase complex (PDC) axis under psychological stress, exploring multidimensional impacts on semen quality.Approved by three tertiary hospitals in Central China, 557 participants were categorized into DAS and non-DAS groups based on DASS-21 scores, with clinical histories and semen samples collected. Targeted metabolomics (ATP/pyruvate/lactate), lipidomics (free fatty acids), and RT-qPCR (PDK1-4, PDH mRNA) were performed. Results revealed significantly reduced sperm motility in the DAS group ( p  < 0.01). Mechanistically, DAS upregulated PDK2/PDK4 expression and suppressed PDH expression, driving metabolic reprogramming and mitochondrial dysfunction. This study provides the first evidence that psychological stress impairs sperm motility via PDK-PDC axis dysregulation, offering novel mechanistic insights and potential therapeutic targets for male infertility. Highlights • First evidence of psychological stress (depression/anxiety/stress) impairing sperm motility through mitochondrial PDK-PDC axis dysregulation. • Mechanistic breakthrough: Stress-induced upregulation of PDK2/PDK4 and suppression of PDH drive metabolic reprogramming, leading to ATP depletion and mitochondrial dysfunction. • Multi-omics validation: Targeted metabolomics and lipidomics reveal reduced TCA cycle intermediates (e.g., citrate, α-ketoglutarate) and elevated free fatty acids (e.g., palmitic acid) in stressed sperm. • Clinical significance: Identifies PDK-PDC axis as a potential therapeutic target for male infertility linked to psychological stress.

Background Vibrio parahaemolyticus is a leading cause of seafood-related bacterial gastroenteritis and outbreaks worldwide. Sensitive and specific detection methods are needed to better control V. parahaemolyticus infections. This study aimed at developing a highly specific and sensitive loop-mediated isothermal amplification (LAMP) assay for detecting V. parahaemolyticus in oysters. A set of five LAMP primers, two outer, two inner, and one loop were designed based on the published V. parahaemolyticus toxR sequence. Specificity of the assay was evaluated using a panel of 36 V. parahaemolyticus and 39 other strains. The assay sensitivity was determined using serial dilutions of V. parahaemolyticus ATCC 27969 culture ranging from 10 8 CFU/ml to extinction. The assay was also tested in experimentally inoculated oyster samples. Results The toxR -based LAMP assay was able to specifically detect all of the 36 V. parahaemolyticus strains without amplification from 39 other strains. The detection limit was 47-470 cells per reaction in pure culture, up to 100-fold more sensitive than that of toxR -PCR. When applied in spiked oysters, the assay was able to detect 1.1 × 10 5 V. parahaemolyticus cells per gram of oyster without enrichment, up to 100-fold more sensitive than that of toxR -PCR. Standard curves generated for detecting V. parahaemolyticus in both pure culture and spiked oyster samples showed good linear relationship between cell numbers and the fluorescence or turbidity signals. Conclusions The toxR -based LAMP assay developed in this study was sensitive, specific, and quantitative, holding great potential for future field detection of V. parahaemolyticus in raw oysters.

Despite their prevalent cancer implications, the in vivo dynamics of SWI/SNF chromatin remodelers and how misregulation of such dynamics underpins cancer remain poorly understood. Using live-cell single-molecule tracking, we quantify the intranuclear diffusion and chromatin-binding of three key subunits common to all major human SWI/SNF remodeler complexes (BAF57, BAF155 and BRG1), and resolve two temporally distinct stable binding modes for the fully assembled complex. Super-resolved density mapping reveals heterogeneous, nanoscale remodeler binding “hotspots” across the nucleoplasm where multiple binding events (especially longer-lived ones) preferentially cluster. Importantly, we uncover distinct roles of the bromodomain in modulating chromatin binding/targeting in a DNA-accessibility-dependent manner, pointing to a model where successive longer-lived binding within “hotspots” leads to sustained productive remodeling. Finally, systematic comparison of six common BRG1 mutants implicated in various cancers unveils alterations in chromatin-binding dynamics unique to each mutant, shedding insight into a multi-modal landscape regulating the spatio-temporal organizational dynamics of SWI/SNF remodelers. Live-cell single-molecule imaging of human SWI/SNF chromatin remodeler complex reveals nanoscale binding “hotspots” in cell nucleus, and uncovers multi-modal aberrations in DNA binding dynamics associated with mutants implicated in various cancers.

Adipose tissue engineering offers a promising approach for breast reconstruction, yet achieving efficient adipose regeneration remains challenging due to poor cell survival and tissue integration. Hence, we developed a three-dimensional (3D) electrospun collagen nanofiber scaffold integrated with adipose-derived mesenchymal stem cells (ADSCs), designed to enhance adipose tissue regeneration by providing a biomimetic extracellular matrix environment. The incorporation of collagen nanofibers enhances cell adhesion and extracellular matrix remodeling, further promoting adipogenic differentiation. Compared to conventional two-dimensional (2D) culture, ADSCs seeded on the scaffold exhibit significantly improved viability and lipid accumulation. In vivo implantation in a rat model demonstrated that the COL-ADSCs composite scaffold increased subcutaneous fat thickness from 2.69 ± 0.10 mm to 3.37 ± 0.11 mm over four weeks, while also promoting collagen remodeling and angiogenesis, as confirmed by CD31-positive staining. Despite these promising outcomes, this study is limited to a small animal model, and further validation in large animal models and clinical settings is necessary. These findings indicate that the COL-ADSCs composite scaffold provides a biomimetic microenvironment that supports ADSC adhesion, differentiation, and tissue remodeling, highlighting its potential as a clinically applicable biomaterial for breast reconstruction.

In this paper, the estimation problem of two parameters of a lifetime distribution with a bathtub-shaped failure rate function based on adaptive progressive type-II censored data is discussed. This censoring scheme allows the experiment to be more efficient in the use of time and cost while ensuring the statistical inference efficiency based on the experimental results. Maximum likelihood estimators are proposed and the approximate confidence intervals for two parameters are computed using the asymptotic normality. Lindley approximation and Gibbs sampling are used to obtain Bayes point estimates and the latter is also used to generate Bayes two-sided credible intervals. Finally, the performance of various estimation methods is evaluated through simulation experiments, and the proposed estimation method is illustrated through the analysis of a real data set.