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In recent years, enterprises have increasingly recognized the pivotal role of external users in driving product innovation. Open innovation platforms (OIPs), which facilitate interactions between companies and external innovators, have emerged as critical conduits in this regard. However, OIP managers face the challenge of motivating innovators to sustain their contributions. While some OIPs have implemented material incentives, the impact of such rewards on users' ongoing innovation efforts remains uncertain. This study utilized a large-scale dataset from an OIP to examine how performance-contingent material rewards influence the subsequent behaviors of online innovators. Employing a quasi-experimental design involving propensity score matching (PSM) and difference-in-differences (DID) analysis, we found that receiving performance-contingent material rewards led to a decrease in the quantity of subsequent ideas generated by innovators. However, these rewarded innovators produced ideas of higher quality. Interestingly, the novelty of ideas submitted by innovators declined following their receiving of rewards. Moreover, newly enlisted innovators exhibited a more positive response to these incentives. Our findings provide valuable insights for platform managers seeking to optimize incentive mechanisms. We suggest adopting diversified incentive approaches and refining incentive strategies to effectively motivate continuous innovation among users on OIPs. [ABSTRACT FROM AUTHOR]

Rapid urbanization has made mountain development an important means to alleviate the shortages of construction land on plains, which has significantly affected regional ecosystem services. In-depth research on the impact of urbanization on ecosystem services under altitude gradients is of great significance to clarify the relationship between the two. Based on data from 2000, 2010 and 2020, the urbanization level and ecosystem services of the study area were evaluated. The spatial correlation of ecosystem services was analyzed by Moran's I. A spatial Durbin model (SDM) was selected to fit the regression. The results show that (1) from 2000 to 2020, the ecosystem services in the study area displayed obvious regional characteristics and aggregation characteristics; (2) in plain areas, the indirect effects of economic, population and land urbanization have a greater negative impact, and compared with shallow mountain areas, deep mountain areas are more negatively affected by economic urbanization and land urbanization; and (3) the significant difference in regression results reflects the rationality of using the spatial Durbin model, as in this paper, and proves the scientific nature of regional coordinated development. The research results provide a reference for the future coordinated development of regional economies and environments. [ABSTRACT FROM AUTHOR]

Monitoring the temperature to determine the fire source locations is essential for controlling the spontaneous combustion in the goaf. Optical fiber sensors are employed to measure the temperature distribution in the goaf. However, due to changes in the geological conditions and the influence of the falling rocks in the goaf, only sensors on the upper side of the uncompacted goaf, due to inclination and coal pillar, may remain. Unilateral sensors are located on the upper side of the goaf, while fire occurs in the center. To investigate the issue with linear unilateral sensors, a two-dimensional inverse method has been developed to determine the location of fire sources by considering heat transfer after a fire inside the goaf. The equations were theoretically solved using Green's function method to obtain the internal temperature distribution of the physical model of the goaf. Sensitivity analysis identified the most crucial parameters in the process of spontaneous heating at different temperature. The fire source location can be determined using a loop method based on the model calculations. We considered a case to validate the model. Accurately identifying the fire source location in the goaf using the unilateral sensors has an essential theoretical and practical significance for fire prevention and fighting. [ABSTRACT FROM AUTHOR]

Background: Anal fistula is a common benign anorectal disease that often requires surgical intervention for effective treatment. In recent years, preoperative colonoscopy as a diagnostic tool in patients with anal fistula has garnered increasing attention due to its potential clinical application value. By investigating underlying inflammatory bowel disease (IBD), polyps, and other abnormalities, preoperative colonoscopy can offer insights to refine surgical strategies and improve patient outcomes. Methods: This retrospective study focused on 1796 patients with various benign anorectal diseases who underwent preoperative intestinal endoscopy and met surgical criteria within the preceding three years at the First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine. Among these patients, 949 diagnosed with anal fistula comprised group A, while 847 patients without anal fistula were assigned to group B for comparison. The investigation encompassed an analysis of general patient information, endoscopic findings, polyp histopathology, distribution of bowel inflammation sites, and results of inflammatory bowel disease assessments between the two patient cohorts. A subgroup analysis was also conducted on 2275 anal fistula patients with no surgical contraindications. This subgroup was categorized into Group A (949 patients who underwent preoperative intestinal endoscopy) and Group C (1326 patients who did not undergo preoperative colonoscopy). The study compared the rates of detecting endoscopic lesions and IBD-related findings between the two subgroups. Results: The study initially confirmed the comparability of general patient information between groups A and B. Notably, the abnormal detection rate in group A was significantly higher than in group B (P < 0.01). In terms of endoscopic findings, the anal fistula group (group A) exhibited higher rates of detecting bowel inflammation, inflammatory bowel disease, and polyps compared to the non-anal fistula group (group B) (P < 0.05). The distribution of inflammation locations indicated higher detection rates in the terminal ileum, ileocecal region, and ascending colon for group A compared to group B (P < 0.05). Although the incidence of IBD in group A was higher than in group B, this difference did not reach statistical significance (P > 0.05). Subsequently, the analysis of the subgroup (groups A and C) revealed a significant disparity in intestinal endoscopic detection rates (P < 0.01) and statistically significant differences in detecting IBD (P < 0.05) and Crohn's disease (P < 0.05) between the two anal fistula subgroups. Conclusions: The findings of this study underscore the substantial clinical value of preoperative colonoscopy in the comprehensive evaluation of patients with anal fistula. Preoperative colonoscopy aids in ruling out localized perianal lesions caused by underlying inflammatory bowel disease, thereby mitigating the likelihood of missed diagnoses and enhancing treatment outcomes. This research highlights the importance of incorporating preoperative colonoscopy as a valuable diagnostic tool in managing anal fistula patients. [ABSTRACT FROM AUTHOR]

Angelica sinensis polysaccharide (ASP) showed increasingly recognized hepatoprotective effects and lipid regulation. Because polysaccharides are typically degraded into fragments or short‐chain fatty acids in the gut, rather than being absorbed in their intact form, it is worth pondering why ASP can regulate hepatic lipid metabolism and protect the liver from damage caused by lipid accumulation. In vivo and in vitro nonalcoholic fatty liver disease (NAFLD) models with lipid accumulation were established to investigate the effect and potential mechanisms of ASP on hepatic fat accumulation. Our results showed that ASP remodeled the composition and abundance of the gut microbiota in high‐fat diet‐fed mice and increased their levels of propionate (0.92 ± 0.30 × 107 vs. 2.13 ± 0.52 × 107) and butyrate (1.83 ± 1.31 × 107 vs. 6.39 ± 1.44 × 107). Sodium propionate significantly increased the expression of estrogen‐related receptor α (ERRα) in liver cells (400 mM sodium propionate for 2.19‐fold increase) and alleviated the progress of NAFLD in methionine–choline‐deficient diet model. Taken together, our study demonstrated that ASP can regulate hepatic lipid metabolism via propionate/ERRα pathway and ultimately relieving NAFLD. Our findings demonstrate that ASP can be used as a health care product or food supplement to prevent NAFLD. [ABSTRACT FROM AUTHOR]

Climate plays a significant role in shaping ecosystem-level carbon sinks. Research on the mechanisms of climate impacts on carbon sinks can contribute to the achievement of carbon neutrality. Investigating the mechanisms by which climate impact on carbon sinks in ecological spaces in the Beijing–Tianjin–Hebei region, one of the most important urban clusters in China, is of great significance. This study employed spatial autocorrelation and econometric models to explore how various climatic factors impact net primary productivity (which is used to represent carbon sink capacity) on a spatial scale. We found an increasing trend in NPP across the Beijing–Tianjin–Hebei urban agglomeration from 2000 to 2020, with marked spatial clustering. Climatic factors exhibited the best fit with the spatial Durbin model, except for average annual precipitation. The remaining factors had significant effects on NPP, showing spatial spillover effects. Results also showed that the average annual temperature, evaporation, and relative humidity had positive impacts on NPP at a local scale but adverse effects at a regional scale. Average annual sunshine duration and the ground temperature had negative effects on NPP locally but promoted effects regionally. Furthermore, the average annual wind speed negatively impacted both local- and regional-scale NPP. This research provides insights into how climate affects carbon sinks on a small spatial scale, offering important references for making policy decisions and improving the accuracy of carbon cycling simulations. [ABSTRACT FROM AUTHOR]

Dendrobium catenatum Lindl. has been long used in China as a functional food and traditional Chinese medicine and polysaccharides from Dendrobium catenatum Lindl. (DOP) exhibited extensive bioactivities. However, studies on the structure-activity relationship of DOP are rarely reported. Here, two polysaccharides named DOP-1 and DOP-2 were obtained, which differed in the ratio of monosaccharide composition and molecular weight. Structural characteristics were elucidated by spectral and chemical analysis. The main structures of DOPs were the linkage of β-(1→4)-D-Manp, with some attached 2-O- or 3-O-acetylated groups. Additionally, the DPPH, hydroxyl and superoxide radicals scavenging assays of DOP-1 and DOP-2 showed that DOP-2 exhibited the higher antioxidant activity, which might be related to its lower molecular weight, higher mannose proportion and lower degree of acetylation, and higher phenolic content. Our results provide a more accurate basis for the application of DOPs in the pharmaceutical and food industries. [ABSTRACT FROM AUTHOR]

As an important part of rural space, the public space landscape has a positive influence on tourists and local residents, and also has an important guiding significance for the sustainable development of rural areas. This study expands the previous research on rural public space, taking the "user-oriented" landscape preference as an important entry point, taking Beijing rural public space as the research object, using eye-tracking technology to objectively reflect the degree of users' preference for the landscape, making quantitative analysis through eye-tracking objective data and subjective satisfaction evaluation to explore the subconscious and aesthetic laws of the subjects, and summarizing the internal driving factors leading to its evolution from the summary of phenomena. This paper explores the visual behavior information and significance behind the "subjective space" created by the countryside for the users, intending to provide strategies for landscape optimization and the management of rural public space in an effort to aid the sustainable development of the countryside. [ABSTRACT FROM AUTHOR]

This study attempted to investigate miR-92a-3p expression in peripheral blood of patients with severe β-thalassemia, and the effect and action mechanism of miR-92a-3p on γ-globin expression and oxidative stress in erythroid precursor cells. CD34+ hematopoietic progenitor cells (HPCs) were isolated from peripheral blood of healthy volunteers and patients with severe β-thalassemia. The levels of miR-92a-3p, BCL11A, and γ-globin were measured in erythroid precursor cells. High-performance liquid chromatography (HPLC) was used to analyze hemoglobin F (HbF) content. HPCs were induced with erythroid differentiation and erythroid precursor cells were then obtained. The relevance between miR-92a-3p and BCL11A was studied using dual luciferase reporter gene assay, and the correlation between miR-92a-3p and HbF was assayed by Pearson correlation analysis. Reactive oxygen species (ROS), glutathione (GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) in erythroid precursor cells were tested to evaluate oxidative stress. Cell apoptosis was examined by flow cytometry. Remarkably higher expression of miR-92a-3p was observed in erythroid precursor cells. Increased expression of miR-92a-3p resulted in elevated levels of γ-globin, GSH, and SOD, reduced expression of ROS and MDA, and decreased cell apoptosis. BCL11A was identified as a target of miR-92a-3p and to be downregulated by miR-92a-3p. Moreover, BCL11A knockdown alone increased the expression of γ-globin, SOD and GSH, and repressed the levels of ROS and MDA and cell apoptosis, and the following inhibition of miR-92a-3p changed these patterns. Our data indicated that miR-92a-3p might increase γ-globin level and reduce oxidative stress and apoptosis in erythroid precursor cells by downregulating BCL11A. [ABSTRACT FROM AUTHOR]

Aim. To investigate the value of neoadjuvant chemotherapy combined with 3D-image-guided afterloading intracavitary radiotherapy in locally advanced cervical cancer (LACC). Methods. Patients with cervical cancer admitted to our hospital from January 1, 2020 to January 1, 2021 were retrieved and analyzed. Cases treated with neoadjuvant chemotherapy and 3D-image-guided afterloading intracavitary radiotherapy were assigned into the observation group (OG), while cases with neoadjuvant chemotherapy alone were assigned into the control group (CG). The short-term effects were determined by RECIST 1.1. Total effective rate TR = complete remission CR + partial remission PR . The serum levels of squamous epithelial cell carcinoma antigen (SCC-Ag), glycoantigen 125 (CA125), carcinoembryonic antigen (CEA), and vascular endothelial growth factor (VEGF) were assessed. In view of the difference between tumor markers and diameters before and after treatment, the correlation between them was analyzed by Pearson test. The adverse events were compared, and the amount of operative bleeding and operation time were evaluated. Cox regression analysis was conducted to assess the influencing factors of 1-year disease-free survival time. Results. Sixty-seven patients were retrieved, including 30 cases in the OG and 37 cases in the CG. There were no significant differences in age, pathological type, tumor size, FIGO stage, past medical history, or smoking history between the two groups (P > 0.05). The TR of patients in the OG was higher than that in the CG (P < 0.05). The SCC-Ag, CA125, CEA, and VEGF levels in the OG decreased markedly after treatment (P < 0.001). The difference in SCC-Ag, CA125, CEA, and VEGF was positively correlated with the difference in tumor diameter before and after treatment (P < 0.05). The incidence of adverse events revealed no obvious difference between the OG and CG (P > 0.05). Cox regression analysis showed that FIGO stage and treatment regimens were independent prognostic factors for 1-year disease-free survival (P < 0.05). Conclusion. Neoadjuvant chemotherapy combined with 3D-image-guided afterloading intracavitary radiotherapy can improve the TR rate and 1-year disease-free survival of LACC patients without increasing the incidence of adverse events. [ABSTRACT FROM AUTHOR]

Objectives: To explore the clinical significance of 18F-FDG metabolic imaging in the diagnosis and biological risk assessment of gastrointestinal stromal tumors (GIST). Methods: This study is a clinical retrospective study. The research subjects were patients with GIST who were admitted to our hospital from January 2014 to December 2019 and underwent 18F-FDG metabolic imaging, and the relationship between biological risk and FDG metabolism was analyzed retrospectively. Results: A total of 32 patients with GIST were included in this study, of which 17 patients had very low and low-risk lesions, and the FDG metabolism level did not increase; five patients had moderate-risk gastric lesions, and the FDG metabolism level was abnormally increased; 10 patients had high-risk lesions, and except for one patient with multiple lesions, the FDG metabolism level of these patients was increased. Conclusions: The level of glucose metabolism is abnormally increased in tumor cells with vigorous mitosis and has higher biological risk. The 18F-FDG metabolism level can determine the biological risk of GIST and whether high-risk lesions involve other tissues and organs, as it more comprehensively reflects the distribution of lesions, the activity of tumor cells and the stage of the disease. [ABSTRACT FROM AUTHOR]

A practical problem in supervised deep learning for medical image segmentation is the lack of labeled data which is expensive and time-consuming to acquire. In contrast, there is a considerable amount of unlabeled data available in the clinic. To make better use of the unlabeled data and improve the generalization on limited labeled data, in this paper, a novel semi-supervised segmentation method via multi-task curriculum learning is presented. Here, curriculum learning means that when training the network, simpler knowledge is preferentially learned to assist the learning of more difficult knowledge. Concretely, our framework consists of a main segmentation task and two auxiliary tasks, i.e. the feature regression task and target detection task. The two auxiliary tasks predict some relatively simpler image-level attributes and bounding boxes as the pseudo labels for the main segmentation task, enforcing the pixel-level segmentation result to match the distribution of these pseudo labels. In addition, to solve the problem of class imbalance in the images, a bounding-box-based attention (BBA) module is embedded, enabling the segmentation network to concern more about the target region rather than the background. Furthermore, to alleviate the adverse effects caused by the possible deviation of pseudo labels, error tolerance mechanisms are also adopted in the auxiliary tasks, including inequality constraint and bounding-box amplification. Our method is validated on ACDC2017 and PROMISE12 datasets. Experimental results demonstrate that compared with the full supervision method and state-of-the-art semi-supervised methods, our method yields a much better segmentation performance on a small labeled dataset. Code is available at https://github.com/DeepMedLab/MTCL. [ABSTRACT FROM AUTHOR]

Urban agglomerations have become the new spatial unit of global economic competition. The intense socioeconomic activities attributed to the development of urban agglomerations are bound to cause damage to the ecosystem services of these urban agglomerations. This study adopts the Beijing-Tianjin-Hebei urban agglomeration in China as the research object, analyzes the spatiotemporal evolution of its critical ecosystem service capacity to address regional ++-development risks from 2000–2018, and employs the Moran's I and geographically weighted regression model to explore the spatial correlation and spatial heterogeneity in the responses of urbanization and ecosystem services. The study indicates that (1) from 2000–2018, the ecosystem services of the Beijing-Tianjin-Hebei urban agglomeration exhibit an increase and then a decline, reaching the highest index in 2015; (2) the ecosystem services reveal obvious spatial heterogeneity with the Yan and Taihang Mountains region as the boundary; (3) built-up area ratio, GDP density, and population density exhibit highly obvious negative correlation driving characteristics on ecosystem services; and (4) the construction land ratio exerts a notable impact on areas with a high ecosystem services, while the spatial response of the effect magnitude of the population and GDP densities is largely influenced by intensive, high-pollution and energy-consuming industries. This article also proposes strategies for the optimization of ecological resources and spatial control, which are dedicated to mitigating the negative impacts of rapid urbanization processes on ecosystem services. [ABSTRACT FROM AUTHOR]

The alleviation of oxidative stress is considered an effective treatment for acetaminophen (APAP)-induced acute liver injury (AILI). However, it remains unknow whether the potential antioxidant Smilax china L. polysaccharide (SCLP) protects against AILI. In this study, in vitro and in vivo experiments were conducted to verify the hepatoprotective effect of SCLP against AILI and explore the potential mechanism. We found that SCLP relieved liver histopathological changes; reversed the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA) and reactive oxygen species (ROS); reversed the change in liver myeloperoxidase (MPO) activity; and enhanced liver antioxidant (GSH, GSH-Px, and t-SOD) levels in APAP-treated mice, thereby significantly reducing APAP-induced liver toxicity. SCLP rescued the cell viability and alleviated oxidative stress in H2O2-treated mouse AML12 (Alpha mouse liver 12) hepatocytes. The results of the mechanistic studies showed that SCLP upregulated nuclear factor E2 related factor (Nrf2) expression, promoted Nrf2 nuclear translocation, and enhanced the ability of Nrf2 to bind antioxidant response elements (AREs). Furthermore, SCLP activated Nrf2-ARE pathway, thus upregulating the expression of oxidative stress-related proteins heme oxygenase 1(HO-1), NAD(P)H quinone dehydrogenase 1(NQO-1) and glutamic acid cysteine ligase catalytic subunit (GCLC). In conclusion, this study confirmed the close correlation between liver protection by SCLP upon exposure to APAP and activated of the Nrf2-ARE pathway. These findings suggest that SCLP is an attractive therapeutic candidate drug for the treatment of AILI. [ABSTRACT FROM AUTHOR]

Acute alcoholic liver injury (AALI) is a threat to human health. Dendrobium officinale polysaccharide (DOP) has the potential to protect the liver by enhancing the anti-oxidative system to maintain the relative balance of ROS (active oxygen species) and antioxidants in AALI mice. However, the dynamic improvement effect of DOP on AALI is still not clear and accurate medication guidance is not available, which limits the clinical application of DOP. Because of the advantages of high sensitivity, noninvasiveness, and visualization, near-infrared (NIR) fluorescence imaging has been widely studied in biochemistry and biomedicine. As the glutathione (GSH) level in the liver is closely related to the progression of AALI, herein, an NIR fluorescent probe for GSH, HCG was used to dynamically evaluate the effect of DOP on AALI mice. In this study, DOP was proven to maintain the relative balance of GSH content in the liver to protect it from damage. To the best of our knowledge, it is the first time to assess the effect of DOP on AALI mice through a NIR fluorescence imaging technique. This study may also provide a potential NIR imaging agent for the clinical research to improve the management of liver injury–related diseases. [ABSTRACT FROM AUTHOR]

In this study, to solve the problems of shock environment and shock isolation, about which there is still a lack of reasonable description, an isokinetic shock distinguishing method (ISDM), which can quantitatively distinguish between shock and forced vibration state, is presented. And the shock isolation performance of an opposed disc springs (ODS) shock isolator with pretightening under boundary friction condition is investigated. The static and dynamic stiffness properties of the ODS shock isolator are discussed. Relying on ISDM, a shock dynamic model of the ODS shock isolator with pretightening under boundary friction condition is established. The average method is adopted to solve the model theoretically. The shock acceleration ratio (SAR), shock displacement ratio (SDR), and relative displacement ratio (RDR) of the model are calculated using the numerical method and verified by experiments. Both numerical and experimental results show that ISDM is effective. And the effects on isolation efficiency of the number of disc springs, additional supporting force, pretightening force, load, and the shock velocity constant of the ODS shock isolator are discussed, which provide guidelines for its further practical application. [ABSTRACT FROM AUTHOR]

Background. Ulcerative colitis (UC) is a complicated disease caused by the interaction between genetic and environmental factors that affect mucosal homeostasis and triggers inappropriate immune response. The purpose of the study was to identify significant biomarkers with potential therapeutic targets and the underlying mechanisms. Methods. The gene expression profiles of GSE48958, GSE73661, and GSE59071 are from the GEO database. Differentially expressed genes (DEGs) were screened by the GEO2R tool. Next, the Database for Annotation, Visualization and Integrated Discovery (DAVID) was applied to analyze gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Then, protein-protein interaction (PPI) was visualized by Cytoscape with Search Tool for the Retrieval of Interacting Genes (STRING). Results. There were a total of 128 common DEGs genes, including 86 upregulated genes enriched in extracellular space, regulation of inflammatory response, chemokine-mediated signaling pathway, response to lipopolysaccharide, and cell proliferation, while 42 downregulated genes enriched in the integral component of the membrane, the integral component of the plasma membrane, apical plasma membrane, symporter activity, and chloride channel activity. The KEGG pathway analysis results demonstrated that DEGs were particularly enriched in cytokine-cytokine receptor interaction, TNF signaling pathway, chemokine signaling pathway, pertussis, and rheumatoid arthritis. 18 central modules of the PPI networks were selected with Cytotype MCODE. Furthermore, 18 genes were found to significantly enrich in the extracellular space, inflammatory response, chemokine-mediated signaling pathway, TNF signaling pathway, regulation of cell proliferation, and immune response via reanalysis of DAVID. Conclusion. The study identified DEGs, key target genes, functional pathways, and pathway analysis of UC, which may provide potential molecular targets and diagnostic biomarkers for UC. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskites have electronic and optoelectronic properties that make them appealing in many device applications1–4. Although many approaches focus on polycrystalline materials5–7, single-crystal hybrid perovskites show improved carrier transport and enhanced stability over their polycrystalline counterparts, due to their orientation-dependent transport behaviour8–10 and lower defect concentrations11,12. However, the fabrication of single-crystal hybrid perovskites, and controlling their morphology and composition, are challenging12. Here we report a solution-based lithography-assisted epitaxial-growth-and-transfer method for fabricating single-crystal hybrid perovskites on arbitrary substrates, with precise control of their thickness (from about 600 nanometres to about 100 micrometres), area (continuous thin films up to about 5.5 centimetres by 5.5 centimetres), and composition gradient in the thickness direction (for example, from methylammonium lead iodide, MAPbI3, to MAPb0.5Sn0.5I3). The transferred single-crystal hybrid perovskites are of comparable quality to those directly grown on epitaxial substrates, and are mechanically flexible depending on the thickness. Lead–tin gradient alloying allows the formation of a graded electronic bandgap, which increases the carrier mobility and impedes carrier recombination. Devices based on these single-crystal hybrid perovskites show not only high stability against various degradation factors but also good performance (for example, solar cells based on lead–tin-gradient structures with an average efficiency of 18.77 per cent). A solution-based lithography-assisted epitaxial-growth-and-transfer method is used to fabricate single-crystal hybrid perovskites on any surface, with precise control of the thickness, area and chemical composition gradient. [ABSTRACT FROM AUTHOR]

We measured time-resolved spectra of laser-produced plasma of Si in a vacuum at the early phase evolution (30–100 ns) and found clear signs of spectral line broadening. Based on the measured line intensities of Si2+ and Si3+ ions, the Saha–Boltzmann method is used to diagnose the electron temperature. The Stark broadening of different high-charge ion lines is combined with a modified Griem semi-empirical formula to diagnose the electron density of Si plasma in the early evolutionary stage. The effects of self-absorption, natural broadening, and Doppler broadening on the spectral profiles were evaluated. We also conducted experiments to verify that current experimental conditions satisfied the local thermodynamic equilibrium conditions. Finally, time evolutions for the electron temperature and electron density in the early stage of plasma evolution were obtained. [ABSTRACT FROM AUTHOR]

Collinear double-pulse (DP) laser-produced plasmas (LPP) of Al in a vacuum under a nanosecond–picosecond configuration were investigated. Combining fast imaging and laser interferometry, expansion profiles and electron density distributions of single pulse (SP) and nanosecond–picosecond collinear DP-LPP with inter-pulse time intervals of 20, 30, and 50 ns were obtained and their evolution characteristics were analyzed. A compression layer was observed during plasma expansion; both its shape and density distribution were controllable by varying the inter-pulse time interval. A special crescent-shaped compression layer was obtained, indicating that a special state of plasma had been prepared by collinear DP-LPP. The results of this study are helpful to a further understanding of expansion and evolution characteristics of collinear DP-LPP and provide an experimental basis for the development of a related theoretical model. [ABSTRACT FROM AUTHOR]

We explored the therapeutic effects of Dendrobium officinale polysaccharide (DOP) on CCl4-induced liver fibrosis with respect to the intestinal hepatic axis using a rat model. Histopathological staining results showed that DOP alleviated extensive fibrous tissue proliferation in interstitium and lessened intestinal mucosal damage. Western blot and PCR results showed that DOP maintained intestinal balance by upregulating the expression of tight junction proteins such as occludin, claudin-1, ZO-1, and Bcl-2 proteins while downregulating the expression of Bax and caspase-3 proteins in the intestine. The transepithelial electrical resistance (TEER) value of the LPS-induced Caco-2 monolayer cell model was increased after DOP administration. These illustrated that DOP can protect the intestinal mucosal barrier function. DOP also inhibited activation of the LPS-TLR4-NF-κB signaling pathway to reduce the contents of inflammatory factors TGF-β and TNF-α, increased the expression of anti-inflammatory factor IL-10, and significantly decreased α-SMA and collagen I expression. These results indicated that DOP maintained intestinal homeostasis by enhancing tight junctions between intestinal cells and reducing apoptosis, thereby inhibiting activation of the LPS-TLR4-NF-κB signaling pathway to protect against liver fibrosis. [ABSTRACT FROM AUTHOR]

Here, we have successfully synthesised and purified multifunctional PLGA-based nanoparticles by the co-encapsulation of an anticancer drug (tetrandrine) and a magnetic material (Fe3O4). The obtained Tet-Fe3O4-PLGA NPs had a uniform spherical shape with a particle size of approximately 199 nm and a negative surface charge of –18.0 mV, displaying a high encapsulation efficiency. Furthermore, TEM studies provided representative images of the purification process of the magnetic nanoparticles with MACS® technology. The MFM and VSM results indicated that both the Fe3O4 NPs and Tet-Fe3O4-PLGA NPs were superparamagnetic. The DSC spectrum demonstrated that Tet was successfully encapsulated within the PLGA-based nanoparticles. Significantly, the release studies revealed NPs had a relatively slower release rate than free Tet after 8 h's initial burst release, which had decreased from 98% to 65% after 24 h. In vitro cellular studies revealed that NPs could effectively penetrate into A549 cells and A549 multicellular spheroids to exert cytotoxicity, displaying a significantly high anti-proliferation effect. Moreover, western blot demonstrated that the co-loaded NPs had a higher anticancer activity by injuring lysosomes to activate the mitochondria pathway and induce A549 cell apoptosis. The magnetic characteristics and high anticancer activity support the use of Tet/Fe3O4 co-loaded PLGA-based nanoparticles as a promising strategy in the treatment of lung cancer. [ABSTRACT FROM AUTHOR]

Given the limited efficacy and potential disadvantages of erythropoiesis-stimulating agents (ESAs) in treating anemia of chronic kidney disease (CKD), the development of better alternative therapies has become a priority. The primary purpose of this study is to investigate the effects of Angelica sinensis polysaccharide (ASP) and its underlying mechanism in the treatment of renal anemia. In the present study, we found that ASP could enhance hypoxic induction of EPO in Hep3B cells, with a mechanism that involved the stabilization of HIF-2α protein. In parallel, ASP rescued the inhibition of EPO, induced by proinflammatory factor TNF-α through blocking GATA2 and NF-κB activation. In a rat model of adenine-induced anemia of CKD, oral administration of ASP corrected anemia and alleviated renal damage and inflammation. By increasing the accumulation of HIF-2α protein and reducing the expression of NF-κB and GATA2 as well as pro-inflammatory cytokines, ASP stimulated both renal and hepatic EPO production, and resulted in an elevation of serum EPO. The restoration of EPO production and EPOR mRNA expression with ASP treatment activated EPOR downstream JAK2/STAT5 and PI3K/Akt signaling, induced their target genes, such as Bcl-xL, Fam132b and Tfrc, and increased Bcl-2/Bax ratio in bone marrow-derived mononuclear cells of CKD rats. Furthermore, we found that ASP suppressed hepatic hepcidin expression, mobilized iron from spleen and liver and increased serum iron. These findings demonstrate that ASP elicits anti-anemic action by restoring EPO production and improving iron availability in the setting of CKD in rats. [ABSTRACT FROM AUTHOR]

To investigate the absorption and delivery of ASP in gastrointestinal (GI) tract, cASP was successfully synthesized by chemically modifying with succinic anhydride and then conjugating with a near infrared fluorescent dye Cy5.5. Then, the capacity of oral absorption of cASP was evaluated. The results demonstrated that cASP had low toxicity and no disruption on the integrity of cell membrane. The endocytosis of cASP into the epithelial cells was time- and energy-dependent, which was mediated by macropinocytosis pathway and clathrin- and caveolae (or lipid raft)-related routes. Otherwise, the actin filaments played a relatively weak role at the same time. The transport study illustrated that cASP could penetrate through the epithelial monolayer and mainly mediated by the same routes as that in the endocytosis experiment. Moreover, bothin vitroUssing chamber andin vivoligated intestinal loops models indicated that cASP could be diffused through the mucus barriers and be absorbed in the whole small intestine. Finally, near-infrared fluorescence imaging presented that cASP could be absorbed and circulated into the blood, then distributed into various organs after oral administration. In conclusion, ASP could be absorbed after oral administration through endocytosis process mainly mediated by macropinocytosis pathway and clathrin- and caveolae (or lipid raft)-related routes, then be absorbed and circulated into blood. This study presents a comprehensive understanding of oral delivery of cASP, which will provide theoretical basis for the clinical application of ASP. [ABSTRACT FROM AUTHOR]

This study compared a new type of polysaccharide-coated magnetic nanoparticles (in which the polysaccharide is derived from Angelica sinensis) with the dextran magnetic nanoparticles in terms of preparation, biocompatibility and tissue distribution in vivo and in vitro in order to examine the potential application of Angelica polysaccharide as a novel carrier in magnetic drug targeting (MDT). Magnetic nanoparticles were prepared by chemical co-precipitation. Their physical and chemical properties were determined by using the transmission electron microscope (TEM), laser particle size analyzer (DLS) and vibrating sample magnetometer (VSM), and their purity and structure by using X-ray diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR). The atomic absorption spectrometric method was performed for quantification of the iron content in different tissues. Histological sections were stained by Prussian blue staining to observe the disposition of magnetic nanoparticles in the liver and kidney. The results showed that both kinds of magnetic nanoparticles possessed small particle size, good dispersion and good magnetic properties. XRD showed the main component of the two magnetic nanoparticles was FeO crystals, and FTIR proved FeO was successfully coated by each polysaccharide, respectively. In vivo, FeO-dextran accumulated in the liver, spleen and lung and FeO- Angelica polysaccharide only in the spleen and lung. It was concluded that Angelica polysaccharide may be applied as a novel carrier in the preparation of magnetic nanoparticles. [ABSTRACT FROM AUTHOR]

Context: Polysaccharide purified Lentinus edodes (Berk.) Sing (Tricholomataceae) has been reported to attenuate oxidative stress in vitro. Objective: This study investigated whether polysaccharides from L. edodes with different molecular weight have protective effects against oxidative stress induced by d-galactose ( d-gal) in vivo, and determined the specific relationship between molecular weight and antioxidant activity. Materials and methods: In the present study, we successfully obtained three purified polysaccharides, coded as LT1, LT2, and LT3, and their molecular weights were 25.5, 306.2, and 605.4 kDa, respectively. The d-gal-treated mice received three polysaccharides once daily for 60 days. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), the content of malondialdehyde (MDA), and erythrocyte membrane fluidity were measured to evaluate the changes of the antioxidant ability. Results: It was demonstrated that the administration of LT1, LT2, and LT3 could improve the antioxidant status to different levels. Furthermore, LT2 exhibited the highest antioxidant ability among these samples in vivo. Indeed, LT2 significantly decreased the content of MDA in liver (15.91 ± 0.31 versus 23.79 ± 1.18 nmol/mg protein for the model group, p < 0.05), enhanced the fluidity of erythrocyte membrane (2.458 ± 0.023 versus 2.167 ± 0.024 for the model group, p < 0.05), and increased the activities of SOD (147.19 ± 4.90 versus 82.26 ± 5.55 units/mg protein for the model group, p < 0.05) and GSH-Px (310.91 ± 6.24 versus 243.64 ± 6.77 units/mg protein for the model group, p < 0.05) in liver. Discussion and conclusion: The LT2 had a potential to be used as a novel natural antioxidant. [ABSTRACT FROM AUTHOR]

In this article, we extend a semiparametric regression estimator with multiplicative adjustment to time series context. The asymptotic theory and results from a simulation study are discussed. Theoretical results and numerical comparison show that, in the time series case, the semiparametric estimator is better than the traditional local polynomial estimator in a wide neighbourhood around the true regression function. [ABSTRACT FROM AUTHOR]

In this article, we extend a class of semi-parametric density estimators to time-series context. The asymptotic theory and simulation study are discussed. Theoretical results and numerical comparison show that in the time-series case, the estimators in this class are better than, or at least competitive with, the traditional kernel density estimator in a broad class of densities. [ABSTRACT FROM AUTHOR]

Trajectory planning is of great value and yet challenging for multirotor unmanned aerial vehicle (UAV) applications in a complex urban environment, mainly due to the complexities of handling cluttered obstacles. The problem further complicates itself in the context of autonomous multi-UAV trajectory planning considering conflict avoidance for future city applications. To tackle this problem, this paper introduces the multi-UAV cooperative trajectory planning (MCTP) problem, and proposes a bilevel model for the problem. The upper level is modeled as an extended multiple traveling salesman problem, aiming at generating trajectories based on heuristic framework for multi-UAV task allocation and scheduling and meanwhile considering UAV kinodynamic properties. The lower level is modeled as a holding time assignment problem to avoid possible spatiotemporal trajectory conflicts, where conflict time difference is analyzed based on the proposed state-time graph method. Numerical studies are conducted in both a 1 km 2 virtual city and 12 km 2 real city with a set of tasks and obstacles settings. The results show that the proposed model is capable of planning trajectories for multi-UAV from the system-level perspective based on the proposed method. [ABSTRACT FROM AUTHOR]

The presence of bike-sharing has a significant influence on the ease of trips by bike, which is one critical aspect of bicycling accessibility (BAcc). The existing measurements of BAcc rarely consider the factor of ownership of bikes, which means that no distinction is made between private-bikes and shared bikes. To measure BAcc more fully, this paper proposes a method to evaluate the influences of bike-sharing on BAcc and to perform the method on a real-world case study in Beijing. It is found that bike-sharing has a boosting effect on BAcc, and the increased rate of BAcc is significantly affected by bicycling frequency and shared-bike availability. A case study in Beijing utilizing geo-location data collected from two major bike-sharing companies (OFO and Mo-bike) illustrates the significance of the impact of bike-sharing on BAcc and the necessity to include bike-sharing in the measurement of BAcc. Besides, the case study shows BAcc around the transit station is better than that over the whole area. Given that bicycling feeds transit, this research lays the foundation for analyzing the combination of bike-sharing and transit from the perspective of accessibility and can further support transportation planning. [ABSTRACT FROM AUTHOR]

Supercapacitors have emerged as an important energy storage technology offering rapid power delivery, fast charging, and long cycle lifetimes. While extending the operational voltage is improving the overall energy and power densities, progress remains hindered by a lack of stable n‐type redox‐active materials. Here, a new Faradaic electrode material comprised of a narrow bandgap donor−acceptor conjugated polymer is demonstrated, which exhibits an open‐shell ground state, intrinsic electrical conductivity, and enhanced charge delocalization in the reduced state. These attributes afford very stable anodes with a coulombic efficiency of 99.6% and that retain 90% capacitance after 2000 charge–discharge cycles, exceeding other n‐dopable organic materials. Redox cycling processes are monitored in situ by optoelectronic measurements to separate chemical versus physical degradation mechanisms. Asymmetric supercapacitors fabricated using this polymer with p‐type PEDOT:PSS operate within a 3 V potential window, with a best‐in‐class energy density of 30.4 Wh kg−1 at a 1 A g−1 discharge rate, a power density of 14.4 kW kg−1 at a 10 A g−1 discharge rate, and a long cycle life critical to energy storage and management. This work demonstrates the application of a new class of stable and tunable redox‐active material for sustainable energy technologies. [ABSTRACT FROM AUTHOR]

Wound healing is a complex process involving diverse changes in multiple cell types where the application of electric fields has been shown to accelerate wound closure. To define the efficacy of therapies based on electric fields, it would be valuable to have a platform to systematically study the effects of electrical stimulation (ES) upon the inflammation phase and the activation of signaling mediators. Here, an in vivo ES model in which flexible electrodes are applied to an animal model for monitoring inflammation in a wound is reported on. Subcutaneous implants of polyvinyl alcohol sponges elicit inflammation response as defined by the infiltration of leukocytes. The wound site is subjected to electric fields using two types of additively fabricated flexible electrode arrays. The sponges are then harvested for flow cytometry analysis to identify changes in the phosphorylation state of intracellular targets. This platform enables studies of molecular mechanisms, as it shows that an application of low‐frequency ES ≤0.5 Hz increases phosphorylation of Erk proteins in recruited leukocytes, identifying a signaling pathway that is activated during the healing process. [ABSTRACT FROM AUTHOR]