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Rationale: The chronic lung disease bronchopulmonary dysplasia (BPD) is the most severe complication of extreme prematurity. BPD results in impaired lung alveolar and vascular development and long-term respiratory morbidity, for which only supportive therapies exist. Umbilical cord–derived mesenchymal stromal cells (UC-MSCs) improve lung structure and function in experimental BPD. Results of clinical trials with MSCs for many disorders do not yet match the promising preclinical studies. A lack of specific criteria to define functionally distinct MSCs persists. Objectives: To determine and correlate single-cell UC-MSC transcriptomic profiles with therapeutic potential. Methods: UC-MSCs from five term donors and human neonatal dermal fibroblasts (HNDFs; control cells of mesenchymal origin) transcriptomes were investigated using single-cell RNA sequencing (scRNA-seq) analysis. The lung-protective effect of UC-MSCs with a distinct transcriptome and control HNDFs was tested in vivo in hyperoxia-induced neonatal lung injury in rats. Measurements and Main Results: UC-MSCs showed limited transcriptomic heterogeneity but were different from HNDFs. Gene Ontology enrichment analysis revealed distinct (progenitor-like and fibroblast-like) UC-MSC subpopulations. Only treatment with progenitor-like UC-MSCs improved lung function and structure and attenuated pulmonary hypertension in hyperoxia-exposed rat pups. Moreover, scRNA-seq identified major histocompatibility complex class I as a molecular marker of nontherapeutic cells and associated with decreased lung retention. Conclusions: UC-MSCs with a progenitor-like transcriptome, but not with a fibroblast-like transcriptome, provide lung protection in experimental BPD. High expression of major histocompatibility complex class I is associated with reduced therapeutic benefit. scRNA-seq may be useful to identify subsets of MSCs with superior repair capacity for clinical application. [ABSTRACT FROM AUTHOR]

Background: Mechanical unloading-induced bone loss threatens prolonged spaceflight and human health. Recent studies have confirmed that osteoporosis is associated with a significant reduction in bone microvessels, but the relationship between them and the underlying mechanism under mechanical unloading are still unclear. Methods: We established a 2D clinostat and hindlimb-unloaded (HLU) mouse model to simulate unloading in vitro and in vivo. Micro-CT scanning was performed to assess changes in the bone microstructure and mass of the tibia. The levels of CD31, Endomucin (EMCN) and histone deacetylase 6 (HDAC6) in tibial microvessels were detected by immunofluorescence (IF) staining. In addition, we established a coculture system of microvascular endothelial cells (MVECs) and osteoblasts, and qRT‒PCR or western blotting was used to detect RNA and protein expression; cell proliferation was detected by CCK‒8 and EdU assays. ChIP was used to detect whether HDAC6 binds to the miRNA promoter region. Results: Bone mass and bone microvessels were simultaneously significantly reduced in HLU mice. Furthermore, MVECs effectively promoted the proliferation and differentiation of osteoblasts under coculture conditions in vitro. Mechanistically, we found that the HDAC6 content was significantly reduced in the bone microvessels of HLU mice and that HDAC6 inhibited the expression of miR-375-3p by reducing histone acetylation in the miR-375 promoter region in MVECs. miR-375-3p was upregulated under unloading and it could inhibit MVEC proliferation by directly targeting low-density lipoprotein-related receptor 5 (LRP5) expression. In addition, silencing HDAC6 promoted the miR-375-3p/LRP5 pathway to suppress MVEC proliferation under mechanical unloading, and regulation of HDAC6/miR-375-3p axis in MVECs could affect osteoblast proliferation under coculture conditions. Conclusion: Our study revealed that disuse-induced bone loss may be closely related to a reduction in the number of bone microvessels and that the modulation of MVEC function could improve bone loss induced by unloading. Mechanistically, the HDAC6/miR-375-3p/LRP5 pathway in MVECs might be a promising strategy for the clinical treatment of unloading-induced bone loss. [ABSTRACT FROM AUTHOR]

Purpose: Pro-relational opportunism (PRO) is of growing concern in today's business environment. The premise of this study is to investigate the issues that remain relatively underexplored in previous research – antecedents of supplier PRO and how supplier PRO affects the trust and commitment of brand firms. Methodology: Three scenario-based experiments were applied to test the hypotheses. In Studies 1a and 1b, we used a 1 × 2 (Study 1a – inter-organizational identification: low versus high; Study 1b – supplier dependence: low versus high) between-subjects design. Participants were asked to evaluate their ethical philosophies after reading the scenarios. We ran a regression analysis to test for the main and interactive effects of inter-organizational identification, supplier dependence, and ethical philosophy on supplier PRO. Study 2 used a 1 × 2 (supplier PRO: PRO acting versus non-PRO acting) between-subjects design. The bootstrapping method using PROCESS was applied to run a mediation analysis. Findings: This study finds that inter-organizational identification, supplier dependence, and managers' ethical philosophy (utilitarianism and relativism) may increase suppliers' PRO behavior. Utilitarianism and relativism positively moderate the effects of inter-organizational identification and supplier dependence on supplier PRO. Supplier PRO has both a direct and negative impact on the brand firm's commitment and an indirect effect mediated by trust. Research implications: This study provides insight into drivers and outcomes of supplier PRO based on the relationships with brand firms. Influences of inter-organizational determinants are dependent on individual factors. This research extends the supply chain opportunism literature beyond the typically dyadic perspective. Practical implications: Brand firms should be cautioned that strong inter-organizational identification may promote supplier PRO. In addition, brand firms should encourage dependent suppliers to find ethical ways to promote alternative attractiveness. In seeking to avoid damage to the trust and commitment of brand firms, suppliers need to establish systems and norms to help managers develop correct ethical philosophies and understand the harm of PRO behavior. Originality/value/contribution: This research may be the first to examine the antecedents of supplier PRO and its boundary conditions in multi-level settings (i.e. inter-organizational and individual levels). Moreover, this study deepens our understanding of opportunism by further developing the consequences of PRO. [ABSTRACT FROM AUTHOR]

The seepage characteristics of clay core walls are crucial for the seepage safety of core rockfill dams, with the permeability coefficient in the unsaturated zone being nonlinear. To accurately determine the unsaturated seepage parameters in clay core rockfill dams, this paper first proposes an enhanced reptile search algorithm (ERSA) by applying three improvement strategies: Arnold's cat chaotic map, nonlinear evolutionary factor, and adaptive Cauchy–Gaussian mutation with variable weight. Then, by integrating the ERSA with the unsaturated seepage finite element method, an inverse modeling approach is developed. This approach is applied to an actual rockfill dam with operational monitoring data to determine the unsaturated seepage parameters of the clay core. Results indicate that the ERSA outperforms the original RSA in test functions, and the calculation results of the seepage parameters determined through inversion are consistent with the monitoring data, showing an overall mean absolute error of 1.086 m. The inverse modeling approach provides a valuable reference for determining unsaturated seepage parameters in similar clay core rockfill dams. [ABSTRACT FROM AUTHOR]

Apis cerana abansis is a unique ecological type of the Asian bees, Apis cerana, distributed mainly over China's western Sichuan plateau. We used Illumina sequencing to obtain the complete mitochondrial genome of A. c. abansis and determined the phylogenetic relationships between A. c. abansis and other Apis cerana ecotypes. The mitogenome of A. c. abansis contains 15 694 bps and includes 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 A+T-rich control region. All protein-coding genes are initiated by ATT or ATG codons and terminated by the typical stop codons, TAA or TAG, but the start codon of the ATP8 gene (one of the 13 protein-coding genes) is ATC. The ML phylogenetic tree based on the 13 protein-coding genes showed that A. c. abansis formed a sister group with the Yun-Gui Plateau Chinese bee and the Central China Chinese bee. This study provides a scientific basis for the protection and breeding of A. c. abansis. [ABSTRACT FROM AUTHOR]

Metalens with nanostructured optical elements are designed to control wavefront shaping at the wavelength‐scale thickness. However, most metalens still suffer from large chromatic aberrations due to phase dispersion, limiting their wide applications for multiple wavelengths. Here, avoiding complex resonant designs or multiple‐layer nanostructures, a simple broadband achromatic metalens by holographic diffraction in the visible spectrum is demonstrated. The hyperbolic phase distributions of multiple discrete wavelengths within a shared aperture and fabricate a broadband achromatic diffractive metalens by flexible direct‐laser‐writing technique is randomly interleaved. The designed polarization‐insensitive metalens modulate the light field by changing the height of the artificial neuron phase units to achieve average focusing efficiencies of 55% in the visible spectrum. This holographic design concept can pave the way to expand achromatic metalenses to multiple spectra. [ABSTRACT FROM AUTHOR]

Recently, functional nanomaterials with unique sizes, shapes, and surface chemistry have been fabricated for various applications in all facets of science and technology. Among these diverse nanomaterials, copper oxide nanoparticles (CuO NPs) have garnered considerable attention due to their unique physicochemical parameters and semiconductor properties. Doping various functional materials in CuO NPs and the fabrication of CuO nanofillers functionalized with natural or synthetic moieties delivers improved antibacterial efficacy in food packaging applications. Moreover, the bactericidal effect of modified CuO NPs against foodborne pathogens largely contributes to their usage in food packaging technology. Therefore, it is essential to fabricate effective antimicrobial CuO nanofillers with minimal or no adverse side effects. This review discusses the synthesis, characterization, surface modification, antibacterial properties, food packaging applications, and toxicological implications of the diverse CuO nanofillers integrated in films and composites. In addition, it highlights their adverse side effects and ways to combat adverse situations. The forthcoming generation is expected to lead a groundbreaking surge of inventive food packaging systems (FPS) based on CuO hybrid nanofillers in food packaging industries. [ABSTRACT FROM AUTHOR]

In order to quantitatively evaluate the sustainability of bus low-fare policy, this study establishes a sustainability evaluation index system for bus low-fare policy by using the PSR (Pressure–State–Response) model. Based on the matter–element extension model and entropy weight method, the sustainability evaluation model of bus low-fare policy is constructed. Finally, taking Shenzhen as an example, this study compares and analyzes the sustainability changes of bus fare policy in 2006, 2012 and 2016. The results show that the sustainability of the bus fare policy does not depend on the attribute of the fare (profit-making fares or public welfare fares): the sustainability of bus low-fare policy is closely related to the supporting fiscal subsidy system. Compared with the cost regulation subsidy system, the quota subsidy system is more conducive to the sustainability of bus low-fare policy. This study provides a decision-making reference for the sustainable development of urban bus low-fare policy. [ABSTRACT FROM AUTHOR]

Background: Multidrug-resistant Acinetobacter baumannii rarely causes community-acquired pneumonia. Here, we report the clinical and genomic characteristics of a multidrug-resistant A. baumannii strain responsible for community-acquired pneumonia in a 31-year-old healthy young women.Methods:A. baumannii strain W2LL was recovered from the alveolar lavage fluid sample of a hospitalized patient with pulmonary infection. Growth rate studies were conducted under various conditions, and virulence assessments were performed using Galleria Mellonella larvae. Whole Genome Sequencing (WGS) was carried out using Oxford Nanopore MinIon and Illumina HiSeq. In silico multilocus sequence typing (MLST), plasmid replicons, antimicrobial resistance genes, and virulence genes were determined using the BacWGSTdb webserver. Phylogenetic analysis between strain W2LL and other closely related A. baumannii genomes retrieved from NCBI database was performed.Results: WGS identified strain W2LL as a rare sporadic lineage sequence type (ST) 1431. In addition to the detection of the β-lactamase gene (blaOXA-98) on the chromosome, blaOXA-58 was found on a 92,034 bp plasmid. Antimicrobial susceptibility testing revealed this strain was resistant to cephalosporins and carbapenems, with initial treatment using cefoxitin proving ineffective. Subsequent treatment with piperacillin-sulbactam combined with levofloxacin led to gradual improvement. Compared to A. baumannii ATCC 17978, W2LL exhibited similar growth rates at 37°C and 42°C, as well as in the presence of zinc. However, strain W2LL exhibited higher virulence phenotype compared to ATCC 17978 in G. mellonella model. The closest relative of A. baumannii W2LL was CAM180_1, another isolate recovered from Cambodia, which differed by 191 SNPs.Conclusion: W2LL is a rare ST1431 carbapenem-resistant A. baumannii strain recovered from a patient with no prior hospitalization or typical risk factors. This underscores the growing menace posed by carbapenem-resistant A. baumannii, no longer limited to hospitalized patients, potentially impacting the broader, younger population. [ABSTRACT FROM AUTHOR]

LncRNAs are emerging as important regulators of gene expression by controlling transcription in the nucleus and by modulating mRNA translation in the cytoplasm. In this study, we reveal a novel function of lncRNA SNHG15 in mediating breast cancer cell invasion through regulating the local translation of CDH2 mRNA. We show that SNHG15 preferentially localizes at the cellular protrusions or cell leading edge and that this localization is directed by IMP1, a multifunctional protein involved in many aspects of RNA regulation. We demonstrate that SNHG15 also forms a complex with nucleolin, allowing nucleolin to be co-transported with SNHG15 to the cell protrusions, where the accumulated nucleolin is able to bind to CDH2 mRNA. Interaction with nucleolin stabilizes local CDH2 mRNA and regulates its translation, thus promoting cell invasive potential. Our findings reveal an underlying mechanism by which lncRNA could serve as a carrier to transport a protein regulator into a specific cell compartment to enhance target mRNA expression. [ABSTRACT FROM AUTHOR]

To investigate the compressive behavior of concrete under a freeze-thaw environment, porosity swelling theory, a damaged plastic model, and an element removal technique are combined to propose a novel mesoscopic numerical model of concrete. The porosity swelling theory is employed to represent the pores evolution behavior of concrete under freeze-thaw cycles, and a novel calculation method for porosity expansion is presented to characterize freeze-thaw cycle times. The damaged plastic model is used to describe the tensile and compressive features of the mortar and interface transition zone. The element removal technique with maximum damage criterion is employed to implement crack propagation. It was demonstrated that the model could capture the freeze-thaw damage and compressive failure of concrete well. The uniaxial compressive behavior of five random mesonumerical models of freeze-thaw concrete was investigated. The results showed that freeze-thaw cycles can cause tensile damage to the mortar near pores and the spalling of surface mortar. With the increase of concrete freeze-thaw cycles, the dispersion degree of the compressive stress–strain curve gradually rises, and the peak stress and peak strain of the freeze-thaw concrete stress–strain curve decrease and increase, respectively. During the freeze-thaw cycles, the sustained preload will decrease the compressive strength because it causes the microcracks to accelerate the damage induced by the freeze-thaw cycles. Then, the influence of mortar and interface transition zone properties on the compressive strength of concrete under freeze-thaw cycles was analyzed. Under 100 freeze-thaw cycles, the maximum attenuation rates of concrete compressive strength increase by 9.39% and 34.26% with the increase of interface transition zone and mortar properties, respectively. Increasing mortar properties and decreasing the sustained preload will enhance the ability of concrete to resist freeze-thaw cycles. [ABSTRACT FROM AUTHOR]

Seepage is the primary cause of dam failures. Conducting regular seepage analysis for dams can effectively prevent accidents from occurring. Accurate and rapid determination of seepage parameters is a prerequisite for seepage calculation in hydraulic engineering. The Whale Optimization Algorithm (WOA) was combined with Support Vector Regression (SVR) to invert the hydraulic conductivity. The good point set initialization method, a cosine-based nonlinear convergence factor, the Levy flight strategy, and the Quasi-oppositional learning strategy were employed to improve WOA. The effectiveness and practicality of Improved Whale Optimization Algorithm (IWOA) were evaluated via numerical experiments. As a case study, the seepage parameters of the Dono Dam located on the Baishui River in China were inversed, adopting the proposed inversion model. The calculated seepage field was reasonable, and the relative error between the simulated head and the measured value at each monitoring point was within 2%. This new inversion method is more feasible and accurate than the existing hydraulic conductivity estimation methods. [ABSTRACT FROM AUTHOR]

Background: Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors with a high prevalence and poor prognosis. It is an urgent problem to deeply understand the molecular mechanism of ESCC and develop effective diagnostic and prognostic methods. Methods: Using tumor tissue and corresponding paracancerous samples from 141 resected ESCC patients, we assessed Jumonji domain-containing protein 6 (JMJD6) expression using Immunohistochemical (IHC) staining. Kaplan-Meier survival analysis and univariate or multivariate analysis were used to investigate the relationship between JMJD6 expression and clinicopathological features. The expression status and prognostic value of JMJD6 were analyzed by bioinformatics and enrichment analysis. Results: The expression of JMJD6 in ESCC samples was higher than that in the corresponding paracancerous samples, and high expression of JMJD6 was positively associated with poor prognosis of ESCC patients. In addition, bioinformatics analysis of the expression and prognosis of JMJD6 in a variety of tumors showed that high expression of JMJD6 was significantly associated with poor overall survival (OS) in ESCC patients. Enrichment analysis indicated that the high expression of genes similar to JMJD6, such as Conserved oligomeric Golgi 1(COG1), Major facilitator superfamily domain 11 (MFSD11) and Death Effector Domain Containing 2 (DEDD2), was associated with poor prognosis of ESCC, suggesting that JMJD6 might be involved in the occurrence and prognosis of ESCC. Conclusion: Our study found that JMJD6 expression was significantly increased in ESCC patients and positively correlated with prognosis, indicating that targeting JMJD6 might be an attractive prognostic biomarker and provides a potential treatment strategy for ESCC. Trial registration: The study was approved by Tangdu Hospital ethics committee (No. TDLL-202110-02). [ABSTRACT FROM AUTHOR]

Ensuring the long-term, efficient, and safe operation of reservoir dams relies on the slope stability of embankment dams. Periodic fluctuations of the reservoir water level due to reservoir scheduling operations make the slope of the reservoir bank vulnerable to instability. To investigate the influence of various factors and their interactions with embankment dam slope stability under changing reservoir water levels, a global sensitivity analysis method is proposed that accounts for seepage–stress coupling. An embankment dam in Shaanxi Province, China, is studied as an example, with COMSOL Multiphysics software simulating the seepage and slope stability of the dam under fluctuating reservoir water level conditions and seepage–stress coupling. The global sensitivity analysis of factors affecting dam slope stability is accomplished by combining Plackett–Burman and Box–Behnken experimental designs, with ANOVA determining the sensitivity of each factor and interaction term. The results demonstrate that during the impoundment period of the reservoir, the saturation line is concave, and the overall stability safety of the dam slope increases first and then tends to be stable, according to the coefficient. The internal friction angle φ, cohesion c, and soil density ρs represent the three most sensitive factors affecting the stability and safety of the dam slope, while c × ρs is a second-order interaction term with significant sensitivity to the stability and safety coefficient of the dam slope. The reservoir drainage period infiltration line is convex, and dam slope stability first reduced and then increased. The magnitude of water level change H, internal friction angle φ, cohesion c, and soil density ρs are the four most sensitive factors for the coefficient of safety of dam slope stability, while c × ρs, H × ρs, and φ × ρs are the second-order interaction terms with significant sensitivity to the coefficient of safety of dam slope stability. These research findings and methods can offer valuable technical support and reference for the investigation and evaluation of the stability of embankment dam slopes. [ABSTRACT FROM AUTHOR]

Surface modification plays a pivotal role in tailoring the functionalities of a solid material. Introduction of antimicrobial function on material surfaces can provide additional protection against life‐threatening bacterial infections. Herein, a simple and universal surface modification method based on surface adhesion and electrostatic interaction of phytic acid (PA) is developed. PA is first functionalized with Prussian blue nanoparticles (PB NPs) via metal chelation and then conjugates with cationic polymers (CPs) through electrostatic interaction. With the aid of surface adherent PA and gravitation effect, the as‐formed PA–PB–CP network aggregates are deposited on the solid materials in a substrate‐independent manner. Synergistic bactericidal effects of "contact‐killing" induced by the CPs and localized photothermal effect caused by the PB NPs endow the substrates with strong antibacterial performance. Membrane integrity, enzymatic activity, and metabolism function of the bacteria are disturbed in contact with the PA–PB–CP coating under near‐infrared (NIR) irradiation. The PA–PB–CP modified biomedical implant surfaces exhibit good biocompatibility and synergistic antibacterial effect under NIR irradiation, and eliminate the adhered bacteria both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

High indoor humidity/temperature pose serious public health threat and hinder industrial productivity, thus adversely impairing the wellness and economy of the entire society. Traditional air conditioning systems for dehumidification and cooling involve significant energy consumption and have accelerated the greenhouse effect. Here, this work demonstrates an asymmetric bilayer cellulose‐based fabric that enables solar‐driven continuous indoor dehumidification, transpiration‐driven power generation, and passive radiative cooling using the same textile without any energy input. The multimode fabric (ABMTF) consists of a cellulose moisture absorption–evaporation layer (ADF) and a cellulose acetate (CA) radiation layer. The ABMTF exhibits a high moisture absorption capacity and water evaporation rate, which quickly reduces the indoor relative humidity (RH) to a comfortable level (40–60% RH) under 1 sun illumination. The evaporation‐driven continuous capillary flow generates a maximum open‐circuit voltage (Voc) of 0.82 V, and a power density (P) up to 1.13 µW cm−3. When a CA layer with high solar reflection and mid‐infrared (mid‐IR) emissivity faces outward, it realizes subambient cooling of ≈12 °C with average cooling power of ≈106 W m−2 at midday under radiation of 900 W m−2. This work brings a new perspective to develop the next‐generation, high performance environmentally friendly materials for sustainable moisture/thermal management and self‐powered applications. [ABSTRACT FROM AUTHOR]

The aim of this work is to study the influence of chamfered perforation and chamfering on the heave and pitch motion of a single floating wind power platform with an anti-heave device. Firstly, the hydrodynamic performance of a single floating body with different chamfers, or without perforation, is calculated and analysed. Secondly, the motion of a model without perforation and with 35° chamfered perforation is captured and studied in a towing tank. The results show that when the wave height is large and the period is small, the perforated device has a certain effect. When the wave height and period are small, the pitch suppression effect of chamfered perforation is more obvious than that of non-chamfered perforation. When the period and wave height are large, the heave suppression effect of non-chamfered perforation is better than that of chamfered perforation. In experimental research, the perforated floating body has a certain effect on restraining the heave and pitch of a floating body under most working conditions, and the effect of restraining the pitch is obviously better than that of restraining the heave. [ABSTRACT FROM AUTHOR]

Seepage is a main cause of dam failure, and its stability analysis is the focus of a dam's design, construction, and management. Because a geological survey can only determine the range of a dam foundation's hydraulic conductivity, hydraulic conductivity inversion is crucial in engineering. However, current inversion methods of dam hydraulic conductivity are either not accurate enough or too complex to be directly used in engineering. Therefore, this paper proposes a new method for the inversion of hydraulic conductivity with high application value in hydraulic engineering using an improved genetic algorithm coupled with an unsaturated equivalent continuum model (IGA–UECM). This method is implemented by a new code that fully considers engineering applicability. In addition to overcoming the premature convergence shortcomings of traditional genetic algorithms, it converges faster than Bayesian optimization and tree-structured Parzen estimator inversion algorithms. This method is verified by comparing the water head from drilling exploration and inversion. The results of the inversion are used to study the influence of a cement grouting curtain layout scheme on the seepage field of the Hami concrete-face rockfill dam in China, which is used as an engineering application case of the IGA–UECM. The law of the seepage field is reasonable, which verifies the validity of the IGA–UECM. The new inversion method of hydraulic conductivity and the proposed cement grouting curtain layout in this study offer possible strategies for the design, construction, and management of concrete-face rockfill dams. [ABSTRACT FROM AUTHOR]

The DeepCwind floating wind turbine platform has become one of the most successful structures for accommercial floating wind farms, and the stability of it is crucial for survivability. Hence, this paper studies an anti-oscillation device with the purpose of reducing the heave and surge effects of the platform. The influence of various chamfered perforations at different sizes of the anti-heave device on the floating platform was further studied by numerical and experimental methods. Furthermore, through an analysis of the surge and heave of the pedestal with anti-heave devices with different chamfered perforations under different wave heights and wave periods, the effects on the hydrodynamic performance of the pedestal were studied. Physical experiments were conducted on a pedestal with anti-heave devices with chamfered perforations under the working conditions of different wave heights and wave periods to verify the reliability of the numerical simulation. The results show that the anti-heave effect of the anti-oscillation device is obvious under the small wave period and large wave height. Under the working conditions of different wave heights and wave periods, different perforated chamfers have different effects on reducing the oscillation of the pedestal, and its effect does not change linearly with an increasing chamfer. Under most working conditions, the anti-heave effect of the 35° chamfered perforated model was found to be the most obvious. [ABSTRACT FROM AUTHOR]

Mechanical unloading-related bone loss adversely harms astronauts' health. Nevertheless, the specific molecular basis underlying the phenomenon has not been completely elucidated. Although the bone microvasculature contributes significantly to bone homeostasis, the pathophysiological role of microvascular endothelial cells (MVECs) in bone loss induced by mechanical unloading is not apparent. Here, we discovered that MC3T3-E1 cells could take up exosomes produced by MVECs under clinorotation-unloading conditions (Clino Exos), which then prevented MC3T3-E1 cells from differentiating into mature osteoblasts. Moreover, miR-92b-3p was found to be highly expressed in both unloaded MVECs and derived exosomes. Further experiments demonstrated that miR-92b-3p was transferred into MC3T3-E1 cells by exosomes, resulting in the suppression of osteogenic differentiation, and that encapsulating miR-92b-3p inhibitor into the Clino Exos blocked their inhibitory effects. Furthermore, miR-92b-3p targeted ELK4 and the expression of ELK4 was lessened when cocultured with Clino Exos. The inhibitor-92b-3p-promoted osteoblast differentiation was partially reduced by siRNA-ELK4. Exosomal miR-92b-3p secreted from MVECs under mechanical unloading has been shown for the first time to partially attenuate the function of osteoblasts through downregulation of ELK4, suggesting a potential strategy to protect against the mechanical unloading-induced bone loss and disuse osteoporosis. [ABSTRACT FROM AUTHOR]

To better understand the seepage field in tailings dam with a drainage structure that combines drainage mat, drainage tube, and geotextile, an equivalent seepage analysis method for the drainage structure is presented. In the method, an equivalent drainage structure is suggested to replace the original drainage. It has enough size to be easily presented in the three-dimensional (3d) model of a tailings dam. According to a back analysis procedure using the quasi-3d models of a tailings dam with original and equivalent drainage structures, the material properties of the equivalent drainage structure can be obtained under the principle of drainage capacity equivalence. It is demonstrated that the suggested method is accurate enough to capture the seepage field in a tailings dam based on comparing the calculated and measured phreatic lines in a tailings dam for verification. Then, the method is employed to investigate the seepage field in a tailings dam in China for a case study. The rise of water level, damage of drainage structure, or increase of tailings discharge speed and time will lift up phreatic line. After terminating tailings discharge, phreatic line will first rise and then fall. The effect of tailings discharge on phreatic line will almost disappear after terminating tailings discharge for 24 h. [ABSTRACT FROM AUTHOR]

Aims: Gut microbiota and metabolites have a profound impact on the maintenance of body health. In this study, we assessed the association between gut microbiota and serum metabolite changes in myositis using 16S rRNA gene sequencing and metabolomics to provide new ideas for screening and treating myositis. Methods and results: Blood and faecal samples were collected from 20 myositis patients and 20 healthy control subjects. Then, 16S rRNA gene sequencing, enzyme‐linked immunosorbent assays and untargeted metabolomics study were performed to evaluate the relationship between gut microbiota and serum metabolites in patients with myositis. Compared to healthy control subjects, the blood samples from the patients with myositis had elevated levels of interleukin‐4 (IL‐4), tumour necrosis factor‐α (TNF‐α), and malondialdehyde (MDA) and decreased superoxide dismutase (SOD) levels. The increase in Bacteroidota (including Bacteroides and Parabacteroides, but not Prevotella) and the decrease in Firmicutes in the patients were accompanied by functional changes in amino acid and lipid metabolism. The gut microbiota (Bacteroides and Parabacteroides) were negatively correlated with the differential serum metabolites (glutamate and taurine). The differential serum metabolites (glutamate, pyrrolidonecarboxylic acid, and taurine) were also correlated with inflammatory factors (IL‐4 and TNF‐α) and oxidative stress indexes (MDA and SOD). Conclusion: Dysbiosis of gut microbiota in patients with myositis was accompanied by changes in inflammatory factors, oxidative stress indexes, and small molecule metabolites in serum. Significance and impact of study: Blood and faecal biomarkers could be used for screening myositis. [ABSTRACT FROM AUTHOR]

The seepage parameters of the dam body and dam foundation are difficult to determine accurately and quickly. Based on the inverse analysis, a Gray Wolf Optimizer (GWO) was introduced into this study to search the target hydraulic conductivity. A novel approach for initialization, a polynomial-based nonlinear convergence factor, and weighting factors based on Euclidean norms and hierarchy were applied to improve GWO. The practicability and effectiveness of Improved Gray Wolf Optimizer (IGWO) were evaluated by numerical experiments. Taking Kakiwa dam located on the Muli River of China as a case, an inversion analysis for seepage parameters was accomplished by adopting the proposed optimization algorithm. The simulated hydraulic heads and seepage volume agree with measurements obtained from piezometers and measuring weir. The steady seepage field of the dam was analyzed. The results indicate the feasibility of IGWO in determining the seepage parameters of Kakiwa dam. [ABSTRACT FROM AUTHOR]

Bone loss caused by mechanical unloading is a threat to prolonged space flight and human health. Epigenetic modifications play a crucial role in varied biological processes, but the mechanism of histone modification on unloading-induced bone loss has rarely been studied. Here, we discovered for the first time that the methyltransferase Setdb1 was downregulated under the mechanical unloading both in vitro and in vivo so as to attenuate osteoblast proliferation. Furthermore, we found these interesting processes depended on the repression of Macrod2 expression triggered by Setdb1 catalyzing the formation of H3K9me3 in the promoter region. Mechanically, we revealed that Macrod2 was upregulated under mechanical unloading and suppressed osteoblast proliferation through the GSK-3β/β-catenin signaling pathway. Moreover, Atf7ip cooperatively contributed to osteoblast proliferation by changing the localization of Setdb1 under mechanical loading. In summary, this research elucidated the role of the Atf7ip/Setdb1/Macrod2 axis in osteoblast proliferation under mechanical unloading for the first time, which can be a potential protective strategy against unloading-induced bone loss. [ABSTRACT FROM AUTHOR]

Osteoimmunology focuses on the intermodulation between bone and the immune system. Lipopolysaccharide (LPS)-induced bone loss models are commonly used to investigate the interface between inflammation and osteoporosis. Circulating exosomes can regulate physiological and pathological processes through exosomal microRNAs and proteins. In this study, we observed reduced osteoblast number and bone formation in LPS-induced bone loss mice (LPS mice). Levels of circulating exosomes were increased by ~ twofold in LPS mice, and the expression of exosomal miRNAs was significantly changed. miRNAs (miRNA-125b-5p, miRNA-132-3p, and miRNA-214-3p) that were reported to inhibit osteoblast activity were significantly increased in the serum exosomes and bone tissues of LPS mice. Additionally, LPS-induced increases in exosomes significantly inhibited the osteogenic differentiation of MC3T3-E1 cells. [ABSTRACT FROM AUTHOR]

To address the problem of dissolution damage during the long-term service of concrete hydraulic buildings, the concrete dissolution damage degree D and contact dissolution loss model with time were proposed by combining the results of indoor concrete dissolution tests. A mathematical model of the evolution of concrete parameters with time was developed. In the context of an underground concrete culvert project, a numerical analysis model of concrete dissolution deterioration was established, according to which the effects of different damage locations on the stress and displacement of concrete culverts were analyzed. The results show that the settlement value of the surface and the soil pore pressure value increase more when the bottom of the culvert is damaged by dissolution, and the settlement of the surface from the bottom damage is about 1.07~1.16 times of that from the top damage. When the damage position deviates from the center line of the culvert, the maximum point of vertical displacement in the transverse settlement trough of the ground surface deviates from the centerline of the culvert by about 3~5 m in the horizontal direction. At the bottom of the culvert, the concrete permeability coefficient reaches 6.957 × 10−8 m/s~8.354 × 10−8 m/s in about 13~16 years after the occurrence of dissolution damage, and local leakage occurs, causing a significant increase in the pore pressure of the soil near the leakage location. The overall settlement and uneven settlement resulting from the dual action of dissolution deterioration of concrete and infiltration pressure can have a serious impact on the upper channel buildings. [ABSTRACT FROM AUTHOR]

Clay core dams are widely applied in reservoir construction, regulating water resource and provide electric power. Leakage is a common problem in reservoir construction, and the leakage amount, which not only affects the economic benefits of the project, but also relates to the safety of the dam body, is difficult to estimate. According to Darcy's law and stable seepage theory, an analytical method can be proposed to calculate the leakage of the clay core dam to gain the seepage flux in a short time. By making some reasonable assumptions, we propose formulae for seepage calculation in different conditions of the position of the groundwater levels, below or above the reservoir bottom. Both sets of formulae contain two parts of leakage calculation, i.e., leakage from the reservoir bottom and leakage from the dam body. By using the proposed analytical method, the leakage of clay core dams can be estimated considering the influence of the groundwater level. To prove the rationality of the analytical method, a simple numerical model can be established using Geo-studio 2020 to calculate the seepage flux of the clay core dam, where relative errors between numerical solutions and analytical solutions are less than 10%. To verify the feasibility in engineering applications, the proposed method was applied to calculate the seepage of a clay core dam in Sichuan, China, which was also calculated using numerical methods by establishing a three-dimensional model. The results show the rationality of the analytical method, which can strike a balance between precision and efficiency. [ABSTRACT FROM AUTHOR]

Analyzing the seepage and stability analysis of embankment dams built on deep overburden layers is an essential aspect of dam design and operation and is of significance to ensure the safe and effective operation of geotechnical and hydraulic structures in reservoir sites. However, in most existing studies, the seepage and dam slope stability were analyzed separately without considering the interaction between the two fields; thus, the actual operating state of the dam could not be accurately reflected. In this paper, an embankment dam located in Yulin, Shaanxi Province, China, built on a deep overburden layer, was selected as a case study for illustration. Considering the hydrogeological and engineering design information of this project, a three-dimensional fine finite element model reflecting the main characteristics of the reservoir site was established. COMSOL Multiphysics software, which is particularly suitable for multifield coupling calculations, was used to conduct a multifield coupling analysis of the safety state of embankment dams on deep overburden layers by modifying and customizing the porous media and subsurface flow module and solid mechanics module. The method to solve the multifield coupling problem was clarified. Notably, the proposed coupling model involved many parameters, which might introduce uncertainties into the model, thereby requiring considerable work for calibration. Therefore, the Morris method was used to identify the sensitivity of the coupled model parameters to the output results. The results show that the established multifield coupling model can effectively address the seepage and stability problems of embankment dams on deep overburden layers, and the dam can safely operate under the existing design scheme. Even under the condition of a magnitude VIII earthquake at the check flood level, the dam does not experience seepage and slope failure. The safety factor of sliding failure of the dam slope is mainly influenced by the internal friction of saturated soil (φs), material cohesion (c), internal friction of unsaturated soil (φu), soil density (ρs) and Poisson's ratio (ν), while the influence of the seepage parameters is generally small. The methodology and results derived from this study can provide technical support and reference to evaluate the safety in terms of the seepage and anti-sliding stability of similar projects. [ABSTRACT FROM AUTHOR]

There exist shear and seepage behaviors on the interface between clay core and concrete slab in clay core dams. In order to investigate the seepage characteristics of the clay–structure interface after shear deformation, a shear-seepage test system is proposed, in which the seepage direction is perpendicular to the shear direction. The shear test and shear-seepage test are performed on clay–metal and clay–mortar interfaces under different normal stresses (100, 200, 400, 800, and 1600 kPa). The shear stress-deformation curves of two clay–structure interfaces exhibit softening behavior and residual friction behavior. The interface roughness can enhance peak and residual shear strength and increase peak displacement. The shear-seepage test results show that specimen permeability decreases first and then increases to a stable value as shear deformation increases under low normal stress, while it decreases continuously and then retains stability under high normal stress. The interface roughness enhances specimen permeability under low normal stress, whereas it has a weak effect on specimen permeability under high normal stress. Compared with initial permeability, shear deformation reduces specimen permeability rather than raise it. The ratio of stabilized permeability coefficient to initial value ranges from 0.6 to 0.8. The clay–structure interface still has a good resistance to seepage failure after shear deformation. The shear dilation features and interface pore decrease caused by shear behavior are the internal attributions of clay–structure specimen permeability evolution. [ABSTRACT FROM AUTHOR]

The deterioration of mortar has an adverse impact on the deformation and stress state of the masonry arch dam, after freeze-thaw cycles, in long-term operation. The purpose of this paper is to investigate the effect of reinforcement grouting on the stress of a thin masonry arch dam and propose a reasonable grouting method in the case of mortar deterioration. The determination of the ultimate grouting pressure is another main focus. The masonry material was generalized by combining a linear elastic model and the proportional weighted average under the condition of deterioration caused by freeze-thaw cycles. A series of analytical methods were proposed for the research of grouting effect on dam stress, based on which the ultimate grouting pressure is calculated in various cases. Results demonstrate that the dam tensile stress may exceed the allowable value in the following operation. Then, some recommended methods for the grouting layout and the estimation of grouting pressure were put forward by integrating the grouting field test with numerical analysis for reinforcement. The research conclusions might have a guiding significance for the reinforcement of similar projects. [ABSTRACT FROM AUTHOR]

Rationale: Bronchopulmonary dysplasia, a chronic respiratory condition originating from preterm birth, is associated with abnormal neurodevelopment. Currently, there is an absence of effective therapies for bronchopulmonary dysplasia and its associated brain injury. In preclinical trials, mesenchymal stromal cell therapies demonstrate promise as a therapeutic alternative for bronchopulmonary dysplasia. Objectives: To investigate whether a multifactorial neonatal mouse model of lung injury perturbs neural progenitor cell function and to assess the ability of human umbilical cord-derived mesenchymal stromal cell extracellular vesicles to mitigate pulmonary and neurologic injury. Methods: Mice at Postnatal Day 7 or 8 were injected intraperitoneally with LPS and ventilated with 40% oxygen at Postnatal Day 9 or 10 for 8 hours. Treated animals received umbilical cord-mesenchymal stromal cell-derived extracellular vesicles intratracheally preceding ventilation. Lung morphology, vascularity, and inflammation were quantified. Neural progenitor cells were isolated from the subventricular zone and hippocampus and assessed for self-renewal, in vitro differentiation ability, and transcriptional profiles. Measurements and Main Results: The multifactorial lung injury model produced alveolar and vascular rarefaction mimicking bronchopulmonary dysplasia. Neural progenitor cells from lung injury mice showed reduced neurosphere and oligodendrocyte formation, as well as inflammatory transcriptional signatures. Mice treated with mesenchymal stromal cell extracellular vesicles showed significant improvement in lung architecture, vessel formation, and inflammatory modulation. In addition, we observed significantly increased in vitro neurosphere formation and altered neural progenitor cell transcriptional signatures. Conclusions: Our multifactorial lung injury model impairs neural progenitor cell function. Observed pulmonary and neurologic alterations are mitigated by intratracheal treatment with mesenchymal stromal cell-derived extracellular vesicles. [ABSTRACT FROM AUTHOR]

The persistence of bacterial infections in humans causes severe adverse health consequences and uncertainties in the global economy. It is of great advantage to develop a rapid tool for the earlier diagnosis and treatment of pathogenic infections. In this work, an active polythiophene derivative containing reactive pentafluorophenyl (PFP) ester groups was prepared via Fe3+-catalyzed oxidative polymerization using PFP thiophene-3-acetate as the monomer. The active polythiophene derivative was conjugated with N,N-dimethyl-1,3-propanediamine via ester-amine reaction, followed by quaternization with 1-bromobutane. The resultant polythiophene derivative (QPDMAPTA) possesses the quaternary ammonium salt groups on its side chain and shows cationic zeta potential of + 12.79 eV at neutral pH. The as-prepared QPDMAPTA exhibits high-level antibacterial action against gram-positive bacteria (Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), and methicillin-resistant S. aureus) as compared with gram-negative bacteria (Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa)). Furthermore, the zeta potential measurements show higher uptake of QPDMAPTA by gram-positive bacteria than the gram-negative bacteria, which depicts the active role of the biological interactions with the charged QPDMAPTA in its differential uptake and bactericidal effect. This phenomenon also facilitates the identification of gram-positive bacteria by observing the color changes of collected bacterial cakes before and after treatment with QPDMAPTA. The fluorescent nature of QPDMAPTA can be used for imaging and detection of gram-positive bacteria via adopting a fluorescent technique. [ABSTRACT FROM AUTHOR]

Due to the characteristics of high heap and large volume, the complex layers of waste, high-water level of leachate, environmental pollution, and slope instability are easily produced. Although many researchers have studied landfill two-dimensional leachate migration law, three-dimensional seepage and stability of landfill sites have been rarely studied. This paper focuses on the heterogeneous characteristics of the landfill piles and analyzes the seepage field and slope stability of the landfill using statistical and numerical analysis methods. The calculated results are compared with the field measurement and literature research data to verify the reliability of the model, which may provide the basis for the design and safe and eco-friendly operation of the landfill. Taking an actual landfill as the research object, the saturated–unsaturated transient model of heterogeneous waste is applied to practical engineering. Considering the landfill process and heterogeneous permeability, the calculated maximum water level is higher. Compared with the homogeneous material, the difference in the water level of each waste layer is about 0.08∼1.88 m, which is not good for the stability of the landfill. Combined with the engineering characteristic distribution of a landfill, the heterogeneous stability model is applied to the actual project to study the influence of different unit weight and shear strength distribution on landfill stability. The established model is suitable for the study of two-dimensional and three-dimensional slope stability of landfill sites. Through the slope stability analysis of the three-dimensional landfill site, it is found that the bank slope of the reservoir is steep and prone to instability failure. In most studies, only the instability of the landfill is of concern, but the bank failure is ignored. In the process of landfill operation and management, while considering the capacity of the landfill, the stability of the bank slope should also be paid attention to, and if necessary, bank slope reinforcement or slope ratio improvement should be carried out. [ABSTRACT FROM AUTHOR]

Medical devices and surgical implants are necessary for tissue engineering and regenerative medicines. However, the biofouling and microbial colonization on the implant surface continues to be a major concern, which is difficult to eradicate and typically necessitates either antibiotic therapy or implant removal. As a result, efficient and eco-friendly bioinspired coating strategies for tethering functional materials or molecules on different medical substrates are highly desirable, especially for endowing versatile surface functionalities. Tannic acid (TA), a well-known tea stain polyphenol, has a good affinity for various substrates and actively inhibits the adhesion and colonization of microbes. Thus, functionalization of polymers, nanomaterials, metal-phenolic networks (MPNs), and proteins using TA bestows the end-products with unique binding or anchoring abilities on various implantable surfaces. This review addresses the recent advancements in the essential biomedical perspective of TA-based bioinspired universal surface coating technologies by focusing on their intrinsic features and ability to produce engineered functional composites. Further, the possible contributions of TA-based composites in antifouling and antibacterial applications on various biomedical substrates are outlined. [ABSTRACT FROM AUTHOR]

Background: The incidence of myasthenia gravis (MG) is increasing, and its characteristics in elderly patients are believed to differ from those in younger patients. However, only a few studies have focused on elderly patients with MG. Objective: To review the characteristics of MG in elderly patients and evaluate whether older age is an independent factor associated with achieving minimal manifestation status (MMS). Methods: This retrospective cohort study included 367 patients (319 non-elderly and 48 elderly patients) with MG enrolled at Xiangya Hospital from September 1, 2016, to December 31, 2018. We collected demographic data and information regarding comorbidities, antibody status, Myasthenia Gravis Foundation of America classification, affected muscle groups, thymoma, and treatment. MMS was defined as the primary outcome. Results: Comorbidities were more common in elderly than in younger patients with MG. Anti-acetylcholine receptor antibody was the dominant subtype, whereas anti-muscle-specific tyrosine kinase antibody was rare and detected only in non-elderly patients. Elderly patients were more likely than younger patients to have generalized MG, but the frequency of thymoma was lower (28.5% vs. 10.4%, p = 0.0078). MMS or better was achieved in 154 (48.3%) and 13 (27.1%) non-elderly and elderly patients, respectively. Older age did not appear to be an independent factor associated with MMS (hazard ratio = 0.625; 95% confidence interval, 0.345–1.131). Conclusions: Older age was not an independent factor for a worse prognosis in patients with MG. The treatment of elderly patients with MG should be individually tailored. [ABSTRACT FROM AUTHOR]

The calcium leaching effect leads to a decrease in the impermeability of the impervious curtain. The inverse analysis strategy was introduced in this study because the calcium leaching parameters of the curtain are not easy to determine. An orthogonal design and the finite element method were used in the strategy. The time-series data of hydraulic head and leakage volume were applied to construct the objective function. The extreme learning machine (ELM) was proposed to build the reflection sets. Genetic algorithm (GA), simulated annealing (SA), sparrow search algorithm (SSA), and particle swarm optimization (PSO) were employed to accelerate the iterative search for the target parameters. The target parameters of the calcium leaching model were used for finite element verification by comparing the monitored and simulated values. The simulated values of hydraulic head and leakage by PSO show good agreement with measurements. The evolution of the curtain permeability coefficient in 100 years was analyzed. The results demonstrate the strategy's feasibility in determining the curtain's calcium leaching parameters and permeability coefficients. [ABSTRACT FROM AUTHOR]

Two kinds of WO3 powders with average size of 100 nm and 5 μm have been used to prepare Pt–WO3 porous composite ceramics, whose WO3 grains are around 1 and 5 μm, respectively. The ceramics with 1 μm WO3 grains show a sensitivity of 755 to 0.08% H2 – 20% O2 – N2 in air of 30% relative humidity (RH) at room temperature, but show no response to this concentration of hydrogen in air of 50% RH due to the depression effect of water, which indicate a relatively low humidity tolerance for the ceramics. In contrast, the ceramics with 5 μm WO3 grains show sensitivities of 1200 and 80 to 0.08% H2 – 20% O2 – N2 at room temperature in air of 30% and 50% RH, respectively, and a sensitivity of 8 to 0.02% H2 – 20% O2 – N2 in air of 70% RH, which represent an ultrahigh humidity tolerance. These results clearly demonstrate that the microstructure of room-temperature hydrogen sensitive metal oxide (MOX) materials exerts a decisive influence on their humidity tolerance. Much attention should be paid to MOX materials with large and even ultra-large MOX grains when room-temperature MOX gas sensors with high humidity tolerance are being developed. [ABSTRACT FROM AUTHOR]

The deformation of dams has always been the focus of dam safety research. To more accurately study the effect of the Duncan–Chang model on the deformation of homogeneous Earth dams, this paper simulates the displacement variation of a homogeneous Earth dam through the finite element method based on the Duncan–Chang E-B model. The sensitivity of the Duncan–Chang E-B model parameters and the dam material density on the displacement of a homogeneous earthen dam in Gansu Province, China, were investigated using single-factor and multifactor analysis methods. The results show that the displacement variation of the dam during the completion and operation periods is consistent with the general rule for Earth and rock dams; the three parameters R f , φ 0 , and Δ φ are more sensitive to dam deformation; and the three parameters m , n , and K are less sensitive to dam deformation. [ABSTRACT FROM AUTHOR]

During the long-term service life of hydraulic structures, the calcium compounds in cement-based materials decompose in the aqueous environment, leading to the continuous change of seepage characteristics. To study the influence of calcium leaching on the concrete dam seepage characteristics, we proposed a new mathematic model of the cement-based material calcium leaching model under advection-diffusion-driven leaching. A solid-liquid nonequilibrium model is adopted to model the decomposition of calcium hydroxide (CH) and calcium silicate hydrate gel (C-S-H). To calculate the porosity more accurately, the proposed model takes the effect of different calcium compound decomposition on the porosity increase in consideration, respectively. Shimantan dam is selected for the three-dimensional (3D) calcium leaching analyses. The 3D finite element model of this dam is analyzed using COMSOL Multiphysics software that is based on the finite element method. Based on the proposed model, seepage characteristics evolutions of the Shimantan dam are studied. Good agreement between the numerical results and the monitored data indicates the accuracy of this simulation. The result shows that after 100 a leaching duration, the uplift pressure increases by 40.8%, and the leakage quantities of the dam body and foundation increase by 48 and 17 times. The rise of uplift pressure and leakage changes caused by curtain deterioration are the main influences of calcium leaching on the dam seepage. The parameter sensitivity results show that it is necessary to reduce CH content in cement-based materials to obtain better calcium leaching durability. This model and simulation results can guide the operation of concrete dams under advection-diffusion-driven leaching. [ABSTRACT FROM AUTHOR]

A balanced, diverse gut microbiota is vital for animal health. The microbial population is shaped by multiple factors including genetic background and environment, but other determinants remain controversial. Numerous studies suggest that the dominant factor is genetic background while others emphasize the environmental factors. Here, we bred asexual hybridization queens (AHQs) of honeybees through nutritional crossbreeding (laid in Apis mellifera colony but bred in Apis cerana colony), sequenced their gut microbiome, and compared it with normally bred sister queens to determine the primary factor shaping the gut microbiota. Our results showed that the dominant genera in the gut microbiota of AHQs were Brevundimonas , Bombella , and Lactobacillus , and its microbial community was more related to A. mellifera queens. The AHQs had a moderate number of different bacterial species and diversity, but total bacterial numbers were low. There were more significant taxa identified in the comparison between AHQ and A. cerana queen according to LEfSe analysis results. The only genetic-specific taxon we figured out was Brevundimonas. The growth of core bacterial abundance showed different characteristics among different queen groups in the first week after emerging. Collectively, this study suggested that the genetic background played a more dominant role than environmental factors in shaping the gut microbiota of honeybee queen and the microbiota of midgut was more sensitive than that of rectum to this impact. [ABSTRACT FROM AUTHOR]

In this Letter, we propose a type of continuous phase vortex gratings (CPVGs), which are able to generate a series of vortex beams with equal or proportional diffracted energies and different topological charges (TCs). A set of CPVGs with dimensions (60 × 60 × 1.1 μm3) are directly designed by mathematical equations, which avoids the use of iterative algorithms. The CPVGs are fabricated by femtosecond laser direct writing (FsLDW) with photoresist, and the experimentally generated vortex beams are in good agreement with the theoretical designs, exhibiting high optical efficiencies. In addition, we realized a CPVG onto the tip of a composite fiber for integrated optical systems. Our work paves the way for applications in optical communications, optical manipulations, and high-performance integrated optics. [ABSTRACT FROM AUTHOR]

Myasthenia gravis (MG) is a rare autoimmune disease. Although the impact of immune cell disorder in MG has been extensively studied, little is known about the transcriptomes of individual cells. Here, we assessed the transcriptional profiles of 39,243 cells by single-cell sequencing and identified 13 major cell clusters, along with 39 subgroups of cells derived from patients with new-onset myasthenia gravis and healthy controls. We found that B cells, CD4+ T cells, and monocytes exhibited more heterogeneity in MG patients. CD4+ T cells were expanded in MG patients. We reclustered B cells and CD4+ T cells, and predict their essential regulators. Further analyses demonstrated that B cells in MG exhibited higher transcriptional activity towards plasma cell differentiation, CD4+ T cell subsets were unbalanced, and inflammatory pathways of monocytes were highly activated. Notably, we discovered a disease-relevant subgroup, CD180− B cells. Increased CD180− B cells in MG are indicative of a high IgG composition and were associated with disease activity and the anti-AChR antibody. Together, our data further the understanding of the cellular heterogeneity involved in the pathogenesis of MG and provide large cell-type-specific markers for subsequent research. [ABSTRACT FROM AUTHOR]

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Recently, the use of the phase-field method (PFM) to simulate the fracture process of brittle materials has attracted increasing attention. The PFM describes the fracture process through a series of differential equations, thus avoiding tedious crack surface tracking and offering advantages in simulating crack initiation, propagation, and bifurcation. The essence of the PFM is a multifield coupling problem, so it is supposed that the COMSOL Multiphysics commercial finite element software, which is particularly suitable for solving multifield coupling problems, should be more efficient and simpler to implement for the PFM. In this paper, a crack propagation model for quasi-brittle materials based on PFM is implemented in COMSOL Multiphysics by means of the solid mechanics module and secondary development interfaces of the partial differential equation (PDE), domain ordinary differential equation (ODE) and differential algebraic equation (DAE). Combined with the collected tensile and shear numerical simulation data, validation studies are carried out both qualitatively and quantitatively. In addition, considering that the PFM involves many parameters would create a significant amount of work for model calibration.Therefore, multifactor sensitivity analysis based on the orthogonal test method is used to identify the parameter' sensitivity. The results show that the use of the solid mechanics module and interfaces of the PDE and domain ODE and DAE are effective for phase-field modelling, and the proposed method could reasonably characterize the whole fracture process of quasi-brittle materials. The sensitivity analysis results revealed that Young's modulus (E) and critical energy release rate (Gc) are the main factors affecting the output results of the model. [ABSTRACT FROM AUTHOR]