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Velocimetry of a motion target within 3‐D space is highly desirable in numerous applicable realms, ranging from explosion and shock wave physics, aerospace engineering to astronomical surveys. However, it is challenging to achieve synchronous, real‐time, and photon‐counting 3‐D velocimetry in modern frameworks as they either require separate multi‐directional detections, and cumbersome calculation processes or are confined to achieve in situ measurements. Here, a new conceptual paradigm is proposed to circumvent these constraints using orbital‐angular‐momentum (OAM)‐driven multi‐point Doppler effect at the photon‐counting level. This scheme, emanating from a single‐direction launch of an on‐demand engineered sequence OAM light mode onto a motion surface, enables simultaneous and independent detections of time‐varying Doppler photon‐count events from three orthogonal echo light paths. Concretely, at the range of motion velocity of 0.25–0.5 ms−1, the relative measurement errors of this proof‐of‐principle prototype are below 1.5%, thus achieving high‐accuracy 3‐D velocimetry at the photon‐counting level for the first time. The exploration of the OAM‐photon‐counting 3‐D velocimetry techniques provides unprecedented advantages in potential applications of synchronous, real‐time, high‐efficiency, and long‐range quantum lidar. [ABSTRACT FROM AUTHOR]

The problem of soil heavy metal pollution in decommissioned sites has become an environmental threat and challenge faced by countries around the world. Establishing a high-precision 3D model of contaminants is essential for pollution risk assessment and accurate monitoring of contaminated sites. In this study, 3D geological model and SSA-XGBoost model are proposed to predict heavy metal concentration in a site. These models can effectively improve the prediction accuracy of soil heavy metals, and the RMSE of the XGBoost model optimized by the SSA algorithm is reduced by 24.3%-34.3%. Compared with other machine learning models, the SSA-XGBoost model has optimal performance in improving the prediction accuracy of soil heavy metals. It is suitable for the areas with significant spatial heterogeneity of soil heavy metals. Using the SSA-XGBoost model and 3D geological model, the 3D spatial distribution characteristics of heavy metals in contaminated soil are determined. The concentration of soil pollutants ranked as As>Pb>Mo, and the overall pollution degree decreases gradually from top to bottom. The pollutants are mainly distributed in the production workshop area in the southwest of the site, and the miscellaneous fill layer is the main soil layer that needs to be remediated. [ABSTRACT FROM AUTHOR]

Liver fibrosis is characterized by excess reactive oxygen species (ROS) production, hepatic stellate cell (HSC) activation, and subsequent extracellular matrix deposition. Since complex pathways regulate HSC activation, the single‐drug therapy efficacy for live fibrosis often falls short of expectations. To address this issue, an HSC‐targeted multifunctional nanoparticle (NP) delivery system co‐loaded with cyclopamine (Cyc; hedgehog inhibitor) and bilirubin (BR; ROS‐scavenger) is designed. The NP, termed RHB, is constructed via chemically conjugating hydrophobic bilirubin to hyaluronic acid (HA), followed by inserting into a cRGDyK peptide modified‐PEG shell. RHB can effectively target activated HSCs in the fibrotic liver by recognizing of the cRGDyK peptide and HA with integrin αvβ3 and CD44 due to their high expression on HSCs. During liver fibrosis, RHB NPs intelligently released Cyc in response to elevated ROS, inhibiting hedgehog signaling and subsequent HSC activation. Meanwhile, RHB NPs exhibited ROS scavenging capability and activated nuclear factor erythroid 2‐related factor 2 (Nrf2) signaling in stimulated HSCs, deactivating HSC. Cyc‐loaded RHB NPs significantly reversed the inflammatory and fibrotic phenotypes in liver fibrotic mice without evident toxicity. In summary, the multifunctional NPs dual‐targeted activated HSCs and deactivated HSC via multiple signaling, effectively ameliorating liver fibrosis, showing great promise for hepatic fibrosis treatment. [ABSTRACT FROM AUTHOR]

Traditional anti‐impact armors and shields are normally made of stiff and hard materials and therefore deficient in flexibility. This greatly limits their applications in protecting objects with complex geometries or significant deformability. Flexible armors can be developed with the application of hard platelets and soft materials, but the lower rigidity of the flexible armors renders them incapable of providing sufficient resistance against impact attacks. To address the inherent conflict between flexibility and impact resistance in traditional armors, here, a composite is developed by hybridizing a shear‐stiffening gel as the matrix and chemically‐strengthened ultrathin glass sheets (CSGS) as the reinforcement. The resulting laminate, termed PCCL, exhibits both high flexibility and high impact resistance. Specifically, at low strain rates, the high ductility of the gel combined with the high flexural strength of the CSGS enables the PCCL to undergo considerable deformation; at high strain rates, on the other hand, the shear stiffening behavior of the gel matrix endows the PCCL with excellent impact resistance manifested by its high performance in energy absorption and high rigidity. With the combination of high flexibility and high impact resistance, the PCCL is demonstrated to be an ideal armor for protecting curved vulnerable objects from impact attacks. [ABSTRACT FROM AUTHOR]

The dried roots of Scutellaria baicalensis (S. baicalensis) have been widely used as a traditional medicine. Recently, climate change and human activities have caused the degeneration of its wildlife habitat. However, there is rare knowledge on the effect and interactive effect of different variables on the spatial heterogeneity of S. baicalensis and how the pattern of suitable cultivation area in China would shift in response to climate change. Based on the Geodetector and Habitat Suitability Index (HSI) method, we proposed an assessment model to identify the critical environmental variable(s) affecting the distribution of suitable cultivation area for S. baicalensis in China and to project its shift under climate change. The results showed that soil and mean annual temperature are two determining variables in its spatial heterogeneity in China. Compared to 1981–2010, future climate change may result in a decrease in its suitable area, and yet may result in an increase in the extremely suitable area (about 1.00–1.35 million km2). S. baicalensis in the southern and northwestern part of its current distribution and the southwestern part and small area of northern China may experience expansion during the 21st century, while S. baicalensis in southern China, the Huang-Huai-Hai plain, and the midwest of northwestern China may experience contractions. Meanwhile, climate warming is expected to shift its distribution northwest through an expansion at the northern (at least 84 km) and western (at least 62 km) boundary and contraction at the southern (at least 529 km) boundary, respectively. These results could provide valuable information to policy-makers for the conservation and scientific introduction of S. baicalensis. [ABSTRACT FROM AUTHOR]

A stoma forms by a series of asymmetric divisions of stomatal lineage precursor cell and the terminal division of a guard mother cell (GMC). GMC division is restricted to once through genetic regulation mechanisms. Here, we show that nitric oxide (NO) is involved in the regulation of the GMC division. NO donor treatment results in the formation of single guard cells (SGCs). SGCs are also produced in plants that accumulate high NO, whereas clustered guard cells (GCs) appear in plants with low NO accumulation. NO treatment promotes the formation of SGCs in the stomatal signalling mutants sdd1, epf1 epf2, tmm1, erl1 erl2 and er erl1 erl2, reduces the cell number per stomatal cluster in the fama‐1 and flp1 myb88, but has no effect on stomatal of cdkb1;1 cyca2;234. Aminocyclopropane‐1‐carboxylic acid (ACC), a positive regulator of GMC division, reduces the NO‐induced SGC formation. Further investigation found NO inhibits ACC synthesis by repressing the expression of several ACC SYNTHASE (ACS) genes, and in turn ACC represses NO accumulation by promoting the expression of HEMOGLOBIN 1 (HB1) encoding a NO scavenger. This work shows NO plays a role in the regulation of GMC division by modulating ACC accumulation in the Arabidopsis cotyledon. Summary statement: Nitric oxide is able to repress the terminal division of guard mother cell (GMC) by reducing the accumulation of aminocyclopropane‐1‐carboxylic acid which is a positive regulator of GMC division. [ABSTRACT FROM AUTHOR]

Pregnane X receptor (PXR) has been reported to regulate glycolipid metabolism. The dysfunction of intestinal barrier contributes to metabolic disorders. However, the role of intestinal PXR in metabolic diseases remains largely unknown. Here, we show that activation of PXR by tributyl citrate (TBC), an intestinal-selective PXR agonist, improves high fat diet (HFD)-induced obesity. The metabolic benefit of intestinal PXR activation is associated with upregulation of β-1,3 galactosyltransferase 5 (B3galt5). Our results reveal that B3galt5 mainly expresses in the intestine and is a direct PXR transcriptional target. B3galt5 knockout exacerbates HFD-induced obesity, insulin resistance and inflammation. Mechanistically, B3galt5 is essential to maintain the integrity of intestinal mucus barrier. B3galt5 ablation impairs the O-glycosylation of mucin2, destabilizes the mucus layer, and increases intestinal permeability. Furthermore, B3galt5 deficiency abolishes the beneficial effect of intestinal PXR activation on metabolic disorders. Our results suggest the intestinal-selective PXR activation regulates B3galt5 expression and maintains metabolic homeostasis, making it a potential therapeutic strategy in obesity. PXR regulates glycolipid metabolism, but the role of intestinal PXR in metabolic diseases remains unknown. Here, the authors show the intestinal-selective PXR activation regulates B3galt5 expression and maintains metabolic homeostasis via regulating the intestinal mucus barrier. [ABSTRACT FROM AUTHOR]

In measuring object rotational velocity using vortex beam, the incident light on a tilted object causes spectral broadening, which significantly interferes with the identification of the true rotational Doppler shift (RDS) peak. We employed a velocity decomposition method to analyze the relationship between the spectral extremum and the central frequency shift caused by the object tilt. Compared with the linear growth trend observed when calculating the object rotational velocity using the frequency peak with the maximum amplitude, the central frequency calculation method effectively reduced the deviation rate of the RDS and velocity measurement value from the true value, even at large tilt angles. This approach increased the maximum tilt angle for a 1% relative error from 0.221 to 0.287 rad, representing a 29.9% improvement. When the tilt angle was 0.7 rad, the velocity measurement deviation reduction rate can reach 5.85%. Our work provides crucial support for achieving high-precision rotational velocity measurement of tilted object. [ABSTRACT FROM AUTHOR]

We previously reported that phenyl- and vinyl-silsesquioxanes (SQs), [RSiO1.5]8,10,12 (R = Ph or vinyl) functionalized with three or more conjugated moieties show red-shifted absorption- and emission features suggesting 3-D conjugation via a cage centered LUMOs. Corner missing [PhSiO1.5]7(OSiMe3)3 and edge opened, end capped [PhSiO1.5]8(OSiMe2)2 (double decker, DD) analogs also offer red shifted spectra again indicating 3-D conjugation and a cage centered LUMO. Copolymerization of DD [PhSiO1.5]8(OSiMevinyl)2 with multiple R–Ar–Br gives copolymers with emission red-shifts that change with degree of polymerization (DP), exhibit charge transfer to F4TNCQ and terpolymer averaged red-shifts suggesting through chain conjugation even with two (O–Si–O) end caps possibly via a cage centered LUMO. Surprisingly, ladder (LL) SQ, (vinylMeSiO2)[PhSiO1.5]4(O2SiMevinyl) copolymers offer emission red-shifts even greater for analogous copolymers requiring a different explanation. Here we assess the photophysical behavior of copolymers of a more extreme SQ form: the half cage [PhSiO1.5]4(OSiMe2Vinyl)4, Vy4HC SQs. We again see small red-shifted absorptions coupled with significant red-shifted emissions, even with just a half cage, thus further supporting the existence of pπ–dπ and/or σ*–π* conjugation through Si–O–Si bonds and contrary to most traditional views of Si–O–Si linked polymers. These same copolymers donate an electron to F4TCNQ generating the radical anion, F4TCNQ−. as further proof of conjugation. Column chromatographic separation of short from longer chain oligomers reveals a direct correlation between DP and emission λmax red-shifts as another indication of conjugation. Further, one- and two-photon absorption and emission spectroscopy reveals multiple excited fluorescence-emitting states in a violation of Kasha's rule wherein emission occurs only from the lowest excited state. Traditional modeling studies again find HOMO LUMO energy levels residing only on the aromatic co-monomers rather than through Si–O–Si bonds as recently found in related polymers. [ABSTRACT FROM AUTHOR]