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For near space unmanned aerial vehicles(NSUAVs), efficient power type is the key to support their long flights. It is considered that the "airborne liquid hydrogen storage + hydrogen fuel cell" scheme is in line with the trend of NSUAVs' greater endurance and larger payloads. In allusion to this scheme, the technology status of hydrogen supply processes, airborne hydrogen tanks, air supply processes and water/heat management for fuel cells are summarized in this paper. Technical analysis and summaries are carried out on hydrogen delivery methods, structures and materials of airborne hydrogen tanks, as well as the influences of low pressure environment on the suction performance of air compressors and heat dissipation performance of fuel cells. The development direction of relevant technologies is also discussed, providing reference for later studies.

Small object detection is one of the main obstacles hindering the development of object detection technology. In small object detection tasks, the performance of universal object detectors often drops sharply. We find through experiments on common models that for small objects, the box prior based on anchor detectors and the point prior without anchor detectors are suboptimal. The current anchor based or anchor-free label allocation methods will generate many false positive small objects samples, resulting in a decrease in detector attention to small objects. Therefore, we propose a new detector CLAHR for small object detection. In response to the issue of high sensitivity to small objects using Intersection over Union (IoU), where small deviations can lead to poor quality of assigned positive and negative samples, CLAHR utilizes the insensitivity of Gaussian distribution to small perturbations of small objects to transform the predicted box and manually annotated true box into Gaussian distribution. Then, CLAHR uses Wasserstein Distance (WD) to measure the distance between the predicted actual receptive field (ARF) and the manually labeled true receptive field (TRF) of the real box, rather than using IoU or central sampling strategies to allocate samples. Considering that IoU threshold based and central sampling strategies tend to favor large objects, we further design a cascaded label assignment (CLA) module to achieve balanced learning for small objects samples. Extensive experiments on the COCO, AI-TOD, and VisDrone datasets demonstrate the effective-eness of the proposed approach.

The availability of high-precision population distribution data is crucial for urban planning and the optimal allocation of resources. To address the limitations of the random forest model in addressing spatial heterogeneity during population spatialisation and the potential for features to be lost or distorted between scale changes, which can result in excessive spatialisation error, this study proposes an optimised population spatialisation model based on the modification of the Human Footprint Index (HFI). A hierarchical feature coding method is used to reduce cross-scale distribution errors. The Human Footprint Index (HFI) was then constructed by selecting a total of seven characteristic factors in five areas, namely, electricity, land use intensity, built environment, transport accessibility, and the level of economic development, which then corrects random forest predictions. The resulting dataset for Suzhou demonstrates the following: (1) the R2 of the HFI-corrected data reaches 92.8%, with an accuracy of 92.3% in medium-density areas, significantly outperforming the single random forest model (81.6%) and WorldPop (69.3%) in overall accuracy; (2) the Pearson correlation coefficient for the HFI-corrected data is 0.96, higher than that of WorldPop (0.94) and RFPop (0.91), further validating the model’s accuracy; and (3) the hierarchical coding method reduces cross-scale errors, improving accuracy by five percentage points.

ObjectiveTo evaluate the changes of the usage of oil， salt， sugar and nutritional knowledge and behavior intervention among diners before and after the establishment of healthy canteens and restaurants in Shanghai.MethodsA comprehensive intervention was conducted through the establishment of healthy canteens and restaurants， encompassing interventions such as oil， salt， and sugar management， improvement of nutritional environment， staffing and training activities， and nutrition labeling guidance. A pre-post self-controlled study design was used to compare changes in oil， salt and sugar usage， as well as diners’ knowledge and behaviors related to nutrition and nutrition labeling， before and after the intervention.ResultsAfter intervention， the total usage of oil， salt， and sugar per meal in the canteens and restaurants decreased by 18.33%， 14.83%， and 13.66%， respectively，and all had statistically significance differences（P

Ecosystem surface plays an important role in maintaining ecological balance and supporting economic development. Accurate and effective identification of ecosystem surface with different ecological uses allows for better categorization and management and contributes to the orderly restoration of ecosystems. In this study, the Human Footprint Index (HFI) is constructed by comprehensively considering the factors of biodiversity, human activity impacts, and geometric features, and combined with the multi-factor knowledge constraints such as changes in land cover. We carry out accurate and effective identification and analysis of ecosystem surfaces, using Changzhou City’s tree cover as a test area. The results show that: (1) The degree of tree cover affected by human activities in Changzhou City varies greatly, and Gross Domestic Product (GDP) and elevation are the main factors affecting the level of the HFI. (2) The distribution of native ecosystem surface and artificial ecosystem surface are uneven, with more than 95% of native ecosystem surfaces distributed in the peripheral areas of the city with higher elevations and farther away from the city center. Artificial ecosystem surfaces are more likely to be found in areas with high GDP and frequent human activities, mainly in urban centers with a large proportion of buildings and along roads. (3) The overall identification accuracy of the ecosystem surface is 83.20%, which is higher in the urban center area with a large proportion of buildings and slightly lower in the area with a large proportion of agricultural production land. The results of the study provide a method for the objective, accurate and effective identification of ecosystem surface, which can improve the enthusiasm of local governments in fulfilling their ecological protection duties and contribute to the efficient achievement of the goal of ecological civilization construction.

In this pre-registered study, we ask how people's emotional responses under threat may be causally affected by what is available to them in the environment, i.e. environmental affordances. For this purpose, we introduce a novel behavioral paradigm using horror movie stimuli to simulate threats. The study illustrates that affordances, specifically items present in the environment, are instrumental in modulating both behavioral choices (approach or avoidance) and emotional expressions of anger and fear. We found that, approach-related resources, such as possession of a weapon, heightened anger and the propensity to confront the threat. This underscores the influence of environmental affordances on emotional regulation and supports a theoretical framework that connects instrumental motives with the variability of emotional and behavioral responses based on affordances. The research, while innovative, recognizes the constraints of simulated threats and controlled settings, suggesting avenues for future exploration in more naturalistic environments.

Soft starters are effective devices used to provide overload protection for motors from large mechanical shocks during the start-up period. However, existing soft starters require additional power supplies, sensors, and complex control elements that pose serious challenges to the integration, versatility, and operability of mechanical transmission system. Herein, we propose a newly soft starter based on the triboelectric nanogenerator (TENG) and electrorheological fluid (ERF) to realize a self-powered mechanical transmission system. Both ERF’s rheological characteristic and the baffle structure play a role in the torque of device. Driven by TENG, the soft starter with optimized baffle achieves a 715% growth in transmission torque compared to that of the device without baffle. And a smooth start is obtained with transmission speeds ranging from 0% to 100%. In application demonstration, this triboelectric soft starter (TSS) has the capacity to gain a smooth operation of the high-speed motor. In contrast, the direct start generates an overshoot, leading to a break in the conveyor belt. The TSS designed in this work with the advantages of self-powered, highly integrated, easy to operate, and low cost, provides a prospective strategy for broadening the application of TENG in mechanical transmission systems.

This study aimed to evaluate the effects of delayed femoral vein ligation on the clinical outcomes of hip disarticulation. We retrospectively reviewed 20 patients with extremity tumors (10 bone tumors and 10 soft tissue sarcomas [STS]) who underwent hip disarticulation. Patients treated for hip disarticulation with synchronous femoral vein ligation (n = 10, regular surgery group) and hip disarticulation with delayed femoral vein ligation (n = 10, delayed ligation group), respectively, were enrolled in this study. The operative time and blood loss were used to evaluate the clinical outcomes. The delayed ligation group had significantly lower operative times than the regular surgery group (P < 0.05). Total, hidden, and intraoperative blood loss were all significantly lower in the delayed ligation group than in the regular surgery group (P < 0.05). However, there were no significant differences in postoperative blood loss. In conclusion, delayed femoral vein ligation could significantly reduce the operative time, hidden blood loss, and intraoperative blood loss in patients undergoing hip disarticulation.

ABSTRACT Pseudomonas aeruginosa ST308 clone has been reported to carry carbapenemase genes such as blaIMP and blaVIM but has been rarely associated with blaNDM-1. A total of 199 P. aeruginosa ST308 clinical and environmental isolates obtained between April 2019 and November 2020 from a tertiary-care hospital in Singapore were characterized using whole-genome sequencing. In addition, 71 blaNDM-1-positive ST308 whole-genome sequences from two other local tertiary-care hospitals in Singapore and 83 global blaNDM-1-negative ST308 whole-genome sequences in public databases were included to assess phylogenetic relationships and perform genome analyses. Phylogenetic analysis and divergent time estimation revealed that blaNDM-1-positive P. aeruginosa ST308 was introduced into Singapore in 2005 (95 % highest posterior density: 2001 to 2008). Core genome, resistome, and analyses of all local blaNDM-1-positive ST308 isolates showed chromosomal integration of multiple antibiotic resistance genes (ARGs) [aac(3)-Id, aac(6′)-Il, aadA6, aadA11, dfrB5, msr(E), floR, sul2, and qnrVC1], which was absent in global blaNDM-1-negative ST308 sequences. Most ARGs and virulence genes were conserved across isolates originating from the three different local hospitals. Close genetic relatedness of the blaNDM-1-positive ST308 clinical and environmental isolates suggests cocirculation between the hospital environment and human hosts with the hospital environment as a potential reservoir. Core genome single nucleotide polymorphism analyses revealed possible clonal transmission of blaNDM-1-positive ST308 isolates between the three hospitals over 7 years. Bloodstream isolates accounted for six of 95 (6.3%) clinical isolates. This study reports the introduction of a pathogenic blaNDM-1-positive P. aeruginosa ST308 more than a decade ago in Singapore and warrants surveillance for wider dissemination. IMPORTANCE P. aeruginosa is a Gram-negative opportunistic pathogen ubiquitously found in the environment and a major cause of nosocomial infections. While the P. aeruginosa ST308 clone has been known to bear blaIMP and blaVIM among global isolates, reports of blaNDM-1-positive P. aeruginosa ST308 are rare. The local blaNDM-1-positive P. aeruginosa ST308 isolates detected in this study appear to be unique to this region, with evidence of chromosomal acquisition of multiple ARGs compared to global blaNDM-1-negative P. aeruginosa ST308 isolates. Surveillance in Singapore and beyond for dissemination is essential to determine whether existing measures are sufficient to control the spread of this ST308 clone.

High-performance terahertz wave detectors at room temperature are still urgently required for a wide range of applications. The available technologies, however, are plagued by low sensitivity, narrow spectral bandwidth, complicated structure, and high noise equivalent power (NEP). Here, we have demonstrated a Weyl semimetal surface plasmon-enhanced high-performance terahertz wave detectors which are based on microdisk array deposited WTe2 nanofilm epitaxially grown on GaN substrate for room temperature operation. With the microdisk array combined the WTe2 layer, strong terahertz wave surface plasmon polaritons can be generated at the WTe2–air interfaces, which results in significant improvement in detecting performance. For the 40 μm diameter microdisk array, a detectivity (D *) of 5.52 × 1012 cm Hz1/2 pW−1 at 0.1 THz is achieved at room temperature. In addition, the responsivity (R A) of 8.78 A W−1 is also obtained. Such high-performance millimeter and terahertz wave photodetectors are useful for wide applications such as high capacity communications, walk-through security, biological diagnosis, spectroscopy, and remote sensing.

Porcine circovirus type 3 (PCV3) is commonly associated with clinical symptoms such as porcine dermatitis and nephropathy syndrome (PDNS)-like lesions, respiratory signs, and reproductive disorders. This study aimed to investigate the epidemiology of PCV3 in a boar stud. The objectives were to detect PCV3 in semen, as well as matched serum, oral fluid, and preputial fluid samples from adult boars using quantitative polymerase chain reaction (qPCR), analyze PCV3-IgG antibody data, and genetically characterize a positive sample. A total of 112 samples from 28 boars were collected from a large-scale pig farm in Guangxi, China. The qPCR results showed that the PCV3 DNA was not detected in semen, with a positive rate of 0% (0/28), while it was detected in serum (3.57%—1/28), oral fluid (64.28%—18/28), and preputial fluid (46.4%—13/28). The seropositivity rate of PCV3-IgG in serum was 82.14% (23/28) according to the indirect enzyme-linked immunosorbent serologic assay (ELISA) results. Phylogenetic analysis revealed that one of the PCV3 isolates belonged to the PCV3c clades. This is the first report of PCV3 detection in preputial fluid from boars. The results suggest that PCV3 is transmitted among boars on pig farms and exhibits epidemic characteristics.

It is particularly appealing for efficient active terahertz (THz) modulators using photonic structures to enhance light–matter interaction. Here, an optical controlled THz modulator is proposed that combines lead sulfide (PbS) quantum dots with subwavelength metallic split-ring resonators (SRRs) for providing field enhancement. The modulation depth reaches 60.3%, which is approximately 3 times larger than the PbS quantum dots film without SRRs (as reference) in the frequency range of 0.1–1.1 THz. Such significant enhanced THz modulation is mainly due to the local THz field enhancement caused by the SRRs, which is consistent with the simulation result.

This study was conducted to assess whether Lactobacillus-containing probiotics could protect intestinal mucosa in rats during traumatic hemorrhagic shock and to determine its underlying mechanisms. Healthy male Sprague–Dawley rats (300 ± 20 g) were randomly divided into four groups. During the study, reverse transcription polymerase chain reaction, western blotting, and hematoxylin and eosin methods were used. There was a significant increase in the expression of toll-like receptor 4 (TLR4) in the rats that experienced traumatic hemorrhagic shock, along with increased mRNA of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6. Pretreatment with Lactobacillus-containing probiotics reduced TLR4 expression, decreased phosphorylation (Ser536) and acetylation (Lys310) of p65, and decreased TNF-α and IL-6 mRNA. The probiotics combined acetate Ringer’s group showed a less severe pathological manifestation compared to the other experimental groups. Lactobacillus-containing probiotics inhibited nuclear factor-kappa B signaling via the downregulation of TLR4, resulting in inflammatory homeostasis, which might be the mechanism whereby Lactobacillus protects the intestinal mucosa from damage caused by the traumatic hemorrhagic shock.

Humans adapt decision strategies in response to environmental demands. Here the authors show that decisions in a virtual foraging task can be modelled based on perceived patch value, which includes reward, competition and threat, and is associated with activity in ventromedial prefrontal and medial cingulate cortices.

Metasurface with simultaneous control of amplitude, phase, and polarization of electromagnetic (EM) waves has drawn great attention in modern optics and photonics. However, conventional metasurfaces are mainly designed for single frequency and functionality. Here, we proposed a simple yet powerful methodology for the design of a dual-frequency multifunctional Janus metasurface. The designed transmissive device with sub-wavelength thickness is not only able to achieve completely independent phase modulation at two preset frequencies, but can also realize efficient asymmetric transmission of EM waves. On the other hand, the out-of-plane symmetry breaking also enables the realization of different functions for opposite propagation directions. As a proof of concept, a Janus beam deflector and a Janus metalens with direction- and frequency-controlled functionalities are demonstrated numerically. A dual-frequency Janus metasurface for direction-dependent meta-holograms is validated both numerically and experimentally. Therefore, we believe the proposed metasurfaces with direction- and frequency-dependent versatile functionalities may have great potential in the fields such as polarization manipulation, chiral sensing and information encryption.

Recent years have seen an increase in research focusing on the amelioration of apple pomace waste for use in the food and nutraceutical industries. Much of this work has concentrated on the characterisation of the polyphenol composition of apple pomace materials to determine their role in conferring nutritional and health benefits. Although apples contain substantial quantities of polymeric procyanidins (condensed tannins), this class of compounds has received limited attention in apple research. This study quantified the polymeric procyanidins in apple pomace extracts using a rapid, methyl-cellulose precipitation (MCP) approach for the first time. In addition, a non-targeted metabolomics approach was applied to determine the most abundant phenolic classes present. Polymeric procyanidins were found to be the most abundant type of polyphenol in apple pomace extracts and were generally oligomeric in nature. Multivariate statistical analysis revealed that the ferric-reducing antioxidant power (FRAP) was most strongly correlated with the polymeric procyanidin concentration. Noting that polymeric procyanidins may not cross the cell layer to exert antioxidant activity in vivo, their presence in apple pomace extracts may therefore overestimate the FRAP. This work highlights the importance of polymeric procyanidins in the phenolic diversity of apple pomaces, and it is proposed that in future studies, rapid MCP assays may be used for their quantification.

Objective To investigate the effect and mechanism of GPRC5A (G protein-coupled receptor family C, member 5, group A) gene on the migration and invasion of osteosarcoma cell line 143B. Methods Differentially expressed genes in metastatic tumors were screened out from the GSE32981 data set, and the survival analysis of the differentially expressed genes was performed in combination with the TCGA database. CCK8 experiment, scratch experiment and Transwell invasion experiment were carried out to detect the effect of GPRC5A knockdown or overexpression on osteosarcoma cell proliferation, migration and invasion. Western blot and RT-qPCR detected the effect of GPRC5A knockdown or over-expression on protein and mRNA levels of EMT related genes. Results The expression of 299 genes was changed in metastatic osteosarcoma, and 37 genes closely related to the survival of osteosarcoma patients were further screened out combined with TCGA database. The results of cell experiments showed that GPRC5A had no effect on the proliferation of osteosarcoma cells, but GPRC5A over-expression could significantly promote osteosarcoma cells migration and invasion(P＜0.05). GPRC5A overexpression promoted the expression of EMT-related proteins N-Cad and Vim, and inhibited the expression of E-Cad(P＜0.05). Conclusions GPRC5A is closely related to the survival of osteosarcoma patients and may promote the migration and invasion of osteosarcoma cells by inducing EMT, so it is believed to be a potential target for anti-osteosarcoma metastasis drugs.

Artificial intelligence(AI) and machine learning(ML) have gradually been widely used in the medical field due to their unique advantages. In cardiovascular diseases, this technology has made some progress for processing complex data from electronic medical record, analyzing disease mechanisms and for predicting prognosis, automatically analyzing and identifying cardiovascular imaging and arrhythmia, and discovering new subtypes of disease. The potential of AI and ML in cardiovascular disease research will bring a new breakthrough in the cardiovascular field.

Most of life’s decisions involve risk and uncertainty regarding whether reward or loss will follow. Decision makers often face uncertainty not only about the likelihood of outcomes (what are the chances that I will get a raise if I ask my supervisor? What are the chances that my supervisor will be upset with me for asking?) but also the magnitude of outcomes (if I do get a raise, how large will it be? If my supervisor gets upset, how bad will the consequences be for me?). Only a few studies have investigated economic decision making with ambiguous likelihoods, and even fewer have investigated ambiguous outcome magnitudes. In the present report, we investigated the effects of ambiguous outcome magnitude, risk, and gains/losses in an economic decision-making task with low stakes (Study 1; $3.60–$5.70; N = 367) and high stakes (Study 2; $6–$48; N = 210) using a within-subjects design. We conducted computational modeling to determine individuals’ preferences/aversions for ambiguous outcome magnitudes, risk, and gains/losses. We additionally investigated the association between trait anxiety and trait depression and decision-making parameters. Our results show that increasing stakes increased ambiguous gain aversion and unambiguous risk aversion but increased ambiguous sure loss preference; participants also became more averse to ambiguous sure gains relative to unambiguous risky gains. There were no significant effects of trait anxiety or trait depression on economic decision making. Our results suggest that as stakes increase, people tend to avoid uncertainty in the gain domain (especially ambiguous gains) but prefer ambiguous vs unambiguous sure losses.

A practical method for organic–inorganic hybrid heterojunction photodetector by spin-coating the cobalt phthalocyanine (CoPc) solution onto the β-gallium oxide (β-Ga2O3) film is available to realize the sensitive detection of ultraviolet light signals. We have carefully measured and calculated the optoelectronic performance of the prepared device. The device demonstrates excellent rectification characteristics under different light intensities, and the rectification ratio reaches 144.96 under 900 μW/cm2 at ±5 V. Benefiting from the construction of CoPc/Ga2O3 heterojunction, the device shows an extremely low dark current of 5.73 fA, a high detectivity of 1.92 × 1017 Jones, a responsivity of 18.4 mA/W, and a high light-to-dark current ratio of 3.76 × 106. In addition, the intrinsic physical mechanism of the device is investigated through the energy band diagram under different conditions. The device is equipped with the possibility to work under self-powered mode and has good stability in the air environment.

In order to improve joint integrity and reduce the amount of intermetallic compounds (IMCs), 6061-T6 Al and AZ31B Mg alloys were successfully joined by stationary shoulder friction stir welding (SSFSW). The stationary shoulder effectively enhanced the joint surface integrity and reduced the thickness reduction of the Al/Mg joint. The elimination of pin adhesion was beneficial to increasing material transfer and then improving interfacial joining length of Al/Mg joint. Extremely thin IMCs layer could be achieved because of the heat sink induced by the stationary shoulder. The maximum tensile strength of the Al/ Mg joint reached 137 MPa at a welding speed of 60 mm/min, rotating velocity of 1000 rpm and offset to Mg sheet of 0.3 mm, which was 130% higher than that of conventional joint. SSFSW is feasible and has the potential to join dissimilar materials with the formation of IMCs, such as Al/Mg alloys, Al/copper alloys, Al/titanium alloys and so on.

A key open question in the study of layered superconducting nickelate films is the role that hydrogen incorporation into the lattice plays in the appearance of the superconducting state. Due to the challenges of stabilizing highly crystalline square planar nickelate films, films are prepared by the deposition of a more stable parent compound which is then transformed into the target phase via a topotactic reaction with a strongly reducing agent such as CaH2. Recent studies, both experimental and theoretical, have introduced the possibility that the incorporation of hydrogen from the reducing agent into the nickelate lattice may be critical for the superconductivity. In this work, we use secondary ion mass spectrometry to examine superconducting La1-xXxNiO2 / SrTiO3 (X = Ca and Sr) and Nd6Ni5O12 / NdGaO3 films, along with non-superconducting NdNiO2 / SrTiO3 and (Nd,Sr)NiO2 / SrTiO3. We find no evidence for extensive hydrogen incorporation across a broad range of samples, including both superconducting and non-superconducting films. Theoretical calculations indicate that hydrogen incorporation is broadly energetically unfavorable in these systems, supporting our conclusion that extensive hydrogen incorporation is not generally required to achieve a superconducting state in layered square-planar nickelates.

Abstract Background To investigate dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) for assessing histopathological and molecular biological features in induced rat epithelial ovarian carcinomas (EOCs). Methods 7,12-dimethylbenz[A]anthracene (DMBA) was applied to induce EOCs in situ in 46 SD rats. Conventional MRI and DCE-MRI were performed to evaluate the morphology and perfusion features of the tumors, including the time-signal intensity curve (TIC), volume transfer constant (Ktrans), rate constant (Kep), extravascular extracellular space volume ratio (Ve) and initial area under the curve (IAUC). DCE-MRI parameters were correlated with histological grade, microvascular density (MVD), vascular endothelial growth factor (VEGF) and fraction of Ki67-positive cells and the serum level of cancer antigen 125 (CA125). Results Thirty-five of the 46 rats developed EOCs. DCE-MRI showed type III TIC more frequently than type II (29/35 vs. 6/35, p 0.05). Ktrans, Kep and IAUC values were positively correlated with MVD, VEGF and Ki67 expression (all p 0.05). Conclusions TIC types and perfusion parameters of DCE-MRI can reflect tumor grade, angiogenesis and cell proliferation to some extent, thereby helping treatment planning and predicting prognosis.

Magnetorheological elastomer (MRE) is one of the most promising smart materials with excellent magnetic-control mechanical properties. This work focuses on the study of the dynamic mechanical properties of MRE under cyclic loadings and periodic magnetic field. The influences of matrix, particle distribution, magnetic field on the dynamic mechanical hysteresis are systematically investigated. It is found that all the normal force, magnetic fields and shear strain would cause a hysteresis in the dynamic mechanical responses of MRE. The continuous cycle tests reveal the hysteresis tended to be saturated after several initial cycles. The hysteresis of MRE under the constant magnetic field can be attributed to the rearrangement of particles, which causes a hardening effect of MRE under the continuous dynamic tests. The periodic magnetic field causes a hysteresis in the dynamic modulus which could be attributed to the irreversible movement of the particles. Among them, the polymer matrix of MRE plays an important role in the dynamic mechanical hysteresis, which suggests more stable molecular chain structures in the matrix reducing the magnitude of hysteresis and improving its stability. Besides, the saturation of the mechanical hysteresis had also been studied, and then relevant physical mechanism was proposed for the qualitative explanation.