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Gardenia jasminoides Ellis, a staple in herbal medicine, has long been esteemed for its purported hepatoprotective properties. Its primary bioactive constituent, geniposide, has attracted considerable scientific interest owing to its multifaceted therapeutic benefits across various health conditions. However, recent investigations have unveiled potential adverse effects associated with its metabolite, genipin, particularly at higher doses and prolonged durations of administration, leading to hepatic injury. Determining the optimal dosage and duration of geniposide administration while elucidating its pharmacological and toxicological mechanisms is imperative for safe and effective clinical application. This study aimed to evaluate the safe dosage and administration duration of geniposide in mice and investigate its toxicological mechanisms within a comprehensive dosage-duration-efficacy/toxicity model. Four distinct mouse models were employed, including wild-type mice, cholestasis-induced mice, globally farnesoid X-activated receptor (FXR) knock out mice, and high-fat diet-induced (HFD) NAFLD mice. Various administration protocols, spanning one or four weeks and comprising two or three oral doses, were tailored to each model's requirements. Geniposide has positive effects on bile acid and lipid metabolism at doses below 220 mg/kg/day without causing liver injury in normal mice. However, in mice with NAFLD, this dosage is less effective in improving liver function, lipid profiles, and bile acid metabolism compared to lower doses. In cholestasis-induced mice, prolonged use of geniposide at 220 mg/kg/day worsened liver damage. Additionally, in NAFLD mice, this dosage of geniposide for four weeks led to intestinal pyroptosis and liver inflammation. These results highlight the lipid-lowering and bile acid regulatory effects of geniposide, but also warn of potential negative impacts on intestinal epithelial cells, particularly with higher doses and longer treatment durations. Therefore, achieving optimal therapeutic results requires a decrease in treatment duration as the dosage increases, in order to maintain a balanced approach to the use of geniposide in clinical settings.
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Gardenia , Iridoides , Ratones Endogámicos C57BL , Animales , Iridoides/farmacología , Iridoides/administración & dosificación , Masculino , Gardenia/química , Ratones , Modelos Animales de Enfermedad , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Ratones Noqueados , Metabolismo de los Lípidos/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Hígado/efectos de los fármacos , Hígado/metabolismo , Colestasis/tratamiento farmacológico , Colestasis/inducido químicamente , Ácidos y Sales Biliares/metabolismo , Relación Dosis-Respuesta a Droga , Receptores Citoplasmáticos y NuclearesRESUMEN
Purpose: Atractylodes macrocephala Koidz is a widely used classical traditional Chinese herbal medicine, that has shown remarkable efficacy in cancers. Colorectal cancer (CRC) is the most common malignant tumor globally. Interferon (IFN)-γ, a prominent cytokine involved in anti-tumor immunity that has cytostatic, pro-apoptotic, and immune-stimulatory properties for the detection and removal of transformed cells. Atractylenolides-II (AT-II) belongs to the lactone compound that is derived from Atractylodes macrocephala Koidz with anti-cancer activity. However, whether AT-II combined with IFN-γ modulates CRC progression and the underlying mechanisms remain unclear. The present study aimed to elucidate the efficacy and pharmaceutical mechanism of action of AT-II combined with IFN-γ synergistically against CRC by regulating the NF-kB p65/PD-L1 signaling pathway. Methods: HT29 and HCT15 cells were treated with AT-II and IFN-γ alone or in combination and cell viability, migration, and invasion were then analyzed using Cell Counting Kit-8 (CCK-8) and Transwell assays, respectively. Furthermore, the underlying mechanism was investigated through western blot assay. The role of AT-II combined with IFN-γ on tumor growth and lung metastases was estimated in vivo. Finally, the population of lymphocytes in tumor tissues of lung metastatic C57BL/6 mice and the plasma cytokine levels were confirmed by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Results: AT-II or the combination IFN-γ significantly inhibited the growth and migration abilities of CRC cells in vitro and in vivo. The biological mechanisms behind the beneficial effects of AT-II combined with IFN-γ were also measured and inhibition of p38 MAPK, FAK, Wnt/ß-catenin, Smad, and NF-kB p65/PD-L1 pathways was observed. Moreover, AT-II combined with IFN-γ significantly inhibited HCT15 xenograft tumor growth and lung metastases in C57BL/6 mice, which was accompanied by lymphocyte infiltration into the tumor tissues and inflammatory response inactivation. Conclusions: The results showed that the AT-II in combination with IFN-γ could be used as a potential strategy for tumor immunotherapy in CRC. More importantly, the mechanism by which AT-II suppressed CRC progressions was by inhibiting the NF-kB p65/PD-L1 signal pathway.
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Unbonded flexible risers consist of several helical and cylindrical layers, which can undergo large bending deformation and can be installed in different configurations to adapt to harsh marine environments; thus, they can be applied to transport oil and gas resources from ultra-deep waters (UDW). Due to their special geometric characteristics, they can ensure sufficient axial tensile stiffness while having small bending stiffness, which can undergo large deflection bending deformation. In recent years, the development of unbonded flexible risers has been moving in an intelligent, integrated direction. This paper presents a review of unbonded flexible risers. Firstly, the form and properties of each interlayer of an unbonded flexible riser are introduced, as well as the corresponding performance and configuration characteristics. In recent years, the development of unbonded flexible risers has been evolving, and the development of machine learning on unbonded flexible risers is discussed. Finally, with emphasis on exploring the design characteristics and working principles, three new types of unbonded flexible risers, an integrated production bundle, an unbonded flexible riser with an anti-H2S layer, and an unbonded flexible riser with a composite armor layer, are presented. The research results show that: (1) the analytical methods of cross-sectional properties of unbonded flexible risers are solved based on ideal assumptions, and the computational accuracy needs to be improved. (2) Numerical methods have evolved from equivalent simplified models to models that account for detailed geometric properties. (3) Compared with ordinary steel risers, the unbonded flexible riser is more suitable for deep-sea resource development, and the structure of each layer can be designed according to the requirements of the actual environment.
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Polylactide/ethylene vinyl alcohol copolymer (PLA/EVOH) blends and fibers with different weight ratios were prepared by melt blending, and two-step melt spinning, respectively. PLA and EVOH in PLA/EVOH blends were immiscible. When EVOH content was ≤60 %, EVOH with the average diameter of about 3 µm was dispersed in PLA matrix uniformly. The dual continuous phases could be observed in PLA/EVOH blend with 70 wt% EVOH. When the EVOH content was ≥80 %, the spherical PLA phase with the diameter of 0.25 to 1 µm was dispersed in EVOH matrix. The introduction of EVOH as nucleating agent could promote the crystallization of PLA. Both PLA and EVOH components in PLA/EVOH blends formed individual crystal phases. The viscosity of PLA/EVOH blend with 5 % EVOH was lower than that of neat PLA. The viscosity of PLA/EVOH blends with the EVOH content of ≥10 % was much higher than that of neat PLA, which showed obvious shear thinning behavior. With the increase of EVOH content, the shear thinning behavior became obvious and the critical shear rate decreased gradually. The drawn PLA/EVOH fibers with the tensile strength of ≥16 cN/tex exhibited good mechanical properties. In addition, the introduction of EVOH could improve the hydrophilicity of PLA fibers.
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Poliésteres , Polivinilos , Poliésteres/química , Polivinilos/química , Viscosidad , Resistencia a la Tracción , CristalizaciónRESUMEN
Precancerous Lesions of Gastric Cancer (PLGC) are an essential step in the advancement of Gastric cancer (GC). Early intervention represents the most effective strategy to impede the development of PLGC. However, additional research is necessary to comprehend the molecular mechanism of PLGC. YQHXD is originated from Si Wu Decoction, has been utilized as an empirical formula for the treatment of PLGC for several years. In this study, we employed network pharmacology, molecular docking, and experimental validation to examine the inhibitory and ameliorative properties of YQHXD on PLGC. Multiple databases were utilized to gather genetic information on drugs in PLGC and YQHXD, in order to obtain cross-targets. We discovered 142 common targets between YQHXD and PLGC. GO and KEGG enrichment analyses indicate that YQHXD treatment of PLGC might be linked with cellular response to oxygen levels and the HIF-1α signaling pathway. Finally, we performed in vitro experiments, of which the results reveal that YQHXD mitigates gastric mucosal atrophy, intestinalization, and heterogeneous hyperplasia, and reduces the expression of inflammatory factors in rats. Therefore, we considered that YQHXD has the potential to delay the PLGC process by inhibiting the HIF-1α signaling pathway.
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Unbonded flexible risers consist of several helical and cylindrical layers, which can undergo large bending deformation and can be installed to different configurations to adapt to harsh marine environments, and is a key equipment in transporting oil and gas resources from Ultra Deep Waters (UDWs) to offshore platforms. The helical interlayer of an unbonded flexible riser makes the structural behavior difficult to predict. In this paper, the axial tensile behavior and the axial tensile ultimate strength of an unbonded flexible riser are studied based on a typical 2.5-inch eight-layer unbonded flexible riser model, and verified through a theoretical method considering the contact between adjacent layers. First, the balance equation of separate layers is deduced by a functional principle, and then the overall theoretical model of an unbonded flexible riser is established considering the geometric relationship between adjacent layers. Then, the numerical model considering the detailed geometric properties of an unbonded flexible riser is established to simulate the axial tensile behavior. Finally, after being verified through the experimental results, the axial tensile stiffness and axial tensile strength of an unboned flexible riser considering the elasticity of the tensile armor layer are studied using the proposed two methods. Additionally, the effect of frictional coefficients is conducted. The numerical and theoretical results show good agreement with the test results, and the friction between adjacent layers would increase the axial tensile stiffness of an unbonded flexible riser.
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Automated delivery of insulin based on continuous glucose monitoring is revolutionizing the way insulin-dependent diabetes is treated. However, challenges remain for the widespread adoption of these systems, including the requirement of a separate glucose sensor, sophisticated electronics and algorithms, and the need for significant user input to operate these costly therapies. Herein, a user-centric glucose-responsive cannula is reported for electronics-free insulin delivery. The cannula-made from a tough, elastomer-hydrogel hybrid membrane formed through a one-pot solvent exchange method-changes permeability to release insulin rapidly upon physiologically relevant varying glucose levels, providing simple and automated insulin delivery with no additional hardware or software. Two prototypes of the cannula are evaluated in insulin-deficient diabetic mice. The first cannula-an ends-sealed, subcutaneously inserted prototype-normalizes blood glucose levels for 3 d and controls postprandial glucose levels. The second, more translational version-a cannula with the distal end sealed and the proximal end connected to a transcutaneous injection port-likewise demonstrates tight, 3-d regulation of blood glucose levels when refilled twice daily. This proof-of-concept study may aid in the development of "smart" cannulas and next-generation insulin therapies at a reduced burden-of-care toll and cost to end-users.
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Glucemia , Insulina , Insulina/administración & dosificación , Animales , Ratones , Glucemia/análisis , Cánula , Diabetes Mellitus Experimental/tratamiento farmacológico , Glucosa/metabolismo , Sistemas de Liberación de Medicamentos/instrumentación , Hidrogeles/química , Sistemas de Infusión de Insulina , Elastómeros/química , Automatización , Diseño de EquipoRESUMEN
Background: The diagnosis of Precancerous Lesions of Gastric Cancer (PLGC) is challenging in clinical practice. We conducted a clinical study by analyzing the information of relevant chromosome copy number variations (CNV) in the TCGA database followed by the UCAD technique to evaluate the value of Chromosomal Instability (CIN) assay in the diagnosis of PLGC. Methods: Based on the screening of gastric cancer related data in TCGA database, CNV analysis was performed to explore the information of chromosome CNV related to gastric cancer. Based on the gastroscopic pathology results, 12 specimens of patients with severe atrophy were screened to analyze the paraffin specimens of gastric mucosa by UCAD technology, and to explore the influence of related factors on them. Results: The results of CNV in TCGA database suggested that chromosome 7, 8, and 17 amplification was obvious in patients with gastric cancer. UCAD results confirmed that in 12 patients with pathologic diagnosis of severe atrophy, five of them had positive results of CIN, with a positive detection rate of 41.7%, which was mainly manifested in chromosome seven and chromosome eight segments amplification. We also found that intestinalization and HP infection were less associated with CIN. And the sensitivity of CIN measurement results was significantly better than that of tumor indicators. Conclusion: The findings suggest that the diagnosis of PLGC can be aided by UCAD detection of CIN, of which Chr7 and 8 may be closely related to PLGC.
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Ulcerative colitis (UC) is an idiopathic, relapsing inflammatory disorder of the colonic mucosa. Pyroptosis contributes significantly to UC. However, the molecular mechanisms of UC remain unexplained. Herein, using transcriptome data and animal experimental validation, we sought to explore pyroptosis-related molecular mechanisms, signature genes, and potential drugs in UC. Gene profiles (GSE48959, GSE59071, GSE53306, and GSE94648) were selected from the Gene Expression Omnibus (GEO) database, which contained samples derived from patients with active and inactive UC, as well as health controls. Gene Set Enrichment Analysis (GSEA), Weighted Gene Co-expression Network Analysis (WGCNA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed on microarrays to unravel the association between UC and pyroptosis. Then, differential expressed genes (DEGs) and pyroptosis-related DEGs were obtained by differential expression analyses and the public database. Subsequently, pyroptosis-related DEGs and their association with the immune infiltration landscape were analyzed using the CIBERSORT method. Besides, potential signature genes were selected by machine learning (ML) algorithms, and then validated by testing datasets which included samples of colonic mucosal tissue and peripheral blood. More importantly, the potential drug was screened based on this. And these signature genes and the drug effect were finally observed in the animal experiment. GSEA and KEGG enrichment analyses on key module genes derived from WGCNA revealed a close association between UC and pyroptosis. Then, a total of 20 pyroptosis-related DEGs of UC and 27 pyroptosis-related DEGs of active UC were screened. Next, 6 candidate genes (ZBP1, AIM2, IL1ß, CASP1, TLR4, CASP11) in UC and 2 candidate genes (TLR4, CASP11) in active UC were respectively identified using the binary logistic regression (BLR), least absolute shrinkage and selection operator (LASSO), random forest (RF) analysis and artificial neural network (ANN), and these genes also showed high diagnostic specificity for UC in testing sets. Specially, TLR4 was elevated in UC and further elevated in active UC. The results of the drug screen revealed that six compounds (quercetin, cyclosporine, resveratrol, cisplatin, paclitaxel, rosiglitazone) could target TLR4, among which the effect of quercetin on intestinal pathology, pyroptosis and the expression of TLR4 in UC and active UC was further determined by the murine model. These findings demonstrated that pyroptosis may promote UC, and especially contributes to the activation of UC. Pyroptosis-related DEGs offer new ideas for the diagnosis of UC. Besides, quercetin was verified as an effective treatment for pyroptosis and intestinal inflammation. This study might enhance our comprehension on the pathogenic mechanism and diagnosis of UC and offer a treatment option for UC.
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Polylactide/chlorogenic acid (PLA/CGA) blends with different weight ratios were prepared by melt mixing, and corresponding PLA/CGA fibers were produced via a two-step melt spinning process. For PLA/CGA blends, CGA was distributed uniformly in the PLA matrix. The intermolecular interactions between CGA and PLA existed. The viscosity of PLA/CGA blends was much lower than that of neat PLA. With the increase of CGA content, the viscosity of PLA/CGA blends decreased. As the CGA content increased, the crystallinity of both PLA/CGA blends and fibers decreased. In addition, the tensile strength of PLA/CGA fibers was slightly lower than that of neat PLA fiber. For PLA/CGA fibers, the 6-fold drawn PLA/CGA fiber with 3 % CGA owned the highest tensile strength of 420 MPa. The ultraviolet (UV) resistance of PLA/CGA fibers were enhanced significantly by the introduction of CGA. When the CGA content was not <3 %, the UV transmittance of PLA/CGA fibers was <8 %. Moreover, PLA/CGA fibers exhibited good antioxidant properties. PLA/CGA fibers with 10 % CGA owned the highest antioxidant rate of >90 %. In addition, the 6-fold drawn PLA/CGA fiber with 10 % CGA presented excellent release performance with a 7-day cumulative CGA release rate of 19 %.
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Antioxidantes , Ácido Clorogénico , Poliésteres/química , CongelaciónRESUMEN
Gastric cancer (GC) is a prevalent malignant tumor within the digestive system, with over 40% of new cases and deaths related to GC globally occurring in China. Despite advancements in treatment modalities, such as surgery supplemented by adjuvant radiotherapy or chemotherapeutic agents, the prognosis for GC remains poor. New targeted therapies and immunotherapies are currently under investigation, but no significant breakthroughs have been achieved. Studies have indicated that GC is a heterogeneous disease, encompassing multiple subtypes with distinct biological characteristics and roles. Consequently, personalized treatment based on clinical features, pathologic typing, and molecular typing is crucial for the diagnosis and management of precancerous lesions of gastric cancer (PLGC). Current research has categorized GC into four subtypes: Epstein-Barr virus-positive, microsatellite instability, genome stability, and chromosome instability (CIN). Technologies such as multi-omics analysis and gene sequencing are being employed to identify more suitable novel testing methods in these areas. Among these, ultrasensitive chromosomal aneuploidy detection (UCAD) can detect CIN at a genome-wide level in subjects using low-depth whole genome sequencing technology, in conjunction with bioinformatics analysis, to achieve qualitative and quantitative detection of chromosomal stability. This editorial reviews recent research advancements in UCAD technology for the diagnosis and management of PLGC.
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BACKGROUND: Current evidence indicates a rising global prevalence of Non-Alcoholic Fatty Liver Disease (NAFLD), which is closely associated to conditions such as obesity, dyslipidemia, insulin resistance, and metabolic syndrome. The relationship between the gut microbiome and metabolites in NAFLD is gaining attention understanding the pathogenesis and progression of dysregulated lipid metabolism and inflammation. The Xie Zhuo Tiao Zhi (XZTZ) decoction has been employed in clinical practice for alleviating hyperlipidemia and symptoms related to metabolic disorders. However, the pharmacological mechanisms underlying the effects of XZTZ remain to be elucidated. PURPOSE: The objective of this study was to examine the pharmacological mechanisms underlying the hypolipidemic and anti-inflammatory effects of XZTZ decoction in a mouse model of NAFLD, as well as the effects of supplementing exogenous metabolites on PO induced cell damage and lipid accumulation in cultured hepatocytes. METHODS: A high-fat diet (HFD) mouse model was established to examine the effects of XZTZ through oral gavage. The general condition of mice and the protective effect of XZTZ on liver injury were evaluated using histological and biochemical methods. Hematoxylin and eosin staining (H&E) staining and oil red O staining were performed to assess inflammatory and lipid accumulation detection, and cytokine levels were quantitatively analyzed. Additionally, the study included full-length 16S rRNA sequencing, liver transcriptome analysis, and non-targeted metabolomics analysis to investigate the relationship among intestinal microbiome, liver metabolic function, and XZTZ decoction. RESULTS: XZTZ had a significant impact on the microbial community structure in NAFLD mice. Notably, the abundance of Ileibacterium valens, which was significantly enriched by XZTZ, exhibited a negative correlation with liver injury biomarkers such as, alanine transaminase (ALT) and aspartate transaminase (AST) activity. Moreover, treatment with XZTZ led to a significant enrichment of the purine metabolism pathway in liver tissue metabolites, with inosine, a purine metabolite, showing a significant positive correlation with the abundance of I. valens. XZTZ and inosine also significantly enhanced fatty acid ß-oxidation, which led to a reduction in the expression of pro-inflammatory cytokines and the inhibition of liver pyroptosis. These effects contributed to the mitigation of liver injury and hepatocyte damage, both in vivo and vitro. Furthermore, the utilization of HPLC fingerprints and UPLC-Q-TOF-MS elucidated the principal constituents within the XZTZ decoction, including naringin, neohesperidin, atractylenolide III, 23-o-Acetylalisol B, pachymic acid, and ursolic acid which are likely responsible for its therapeutic efficacy. Further investigations are imperative to fully uncover and validate the pharmacodynamic mechanisms underlying these observations. CONCLUSION: The administration of XZTZ decoction demonstrates a protective effect on the livers of NAFLD mice by inhibiting lipid accumulation and reducing hepatocyte inflammatory damage. This protective effect is mediated by the upregulation of I.valens abundance in the intestine, highlighting the importance of the gut-liver axis. Furthermore, the presesnce of inosine, adenosine, and their derivatives are important in promoting the protective effects of XZTZ. Furthermore, the in vitro approaching, we provide hitherto undocumented evidence indicating that the inosine significantly improves lipid accumulation, inflammatory damage, and pyroptosis in AML12 cells incubated with free fatty acids.
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Microbioma Gastrointestinal , Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Piroptosis , ARN Ribosómico 16S , Hígado , Metabolismo de los Lípidos , Dieta Alta en Grasa/efectos adversos , Ácidos Grasos no Esterificados/metabolismo , Purinas/farmacología , Inosina/metabolismo , Inosina/farmacología , Inosina/uso terapéutico , Ratones Endogámicos C57BLRESUMEN
BACKGROUND: Since most infants are usually discharged before age 48-72 hours, peak bilirubin levels will almost always occur after discharge. Parents may be the first to observe the onset of jaundice after discharge, but visual assessment is unreliable. The jaundice colour card (JCard) is a low-cost icterometer designed for the assessment of neonatal jaundice. The objective of this study was to evaluate parental use of JCard to detect jaundice in neonates. METHODS: We conducted a multicentre, prospective, observational cohort study in nine sites across China. A total of 1161 newborns ≥35 weeks of gestation were enrolled in the study. Measurements of total serum bilirubin (TSB) levels were based on clinical indications. The JCard measurements by parents and paediatricians were compared with the TSB. RESULTS: JCard values of parents and paediatricians were correlated with TSB (r=0.754 and 0.788, respectively). The parents' and paediatricians' JCard values 9 had sensitivities of 95.2% vs 97.6% and specificities of 84.5% vs 71.7% for identifying neonates with TSB ≥153.9 µmol/L. The parents' and paediatricians' JCard values 15 had sensitivities of 79.9% vs 89.0% and specificities of 66.7% vs 64.9% for identifying neonates with TSB ≥256.5 µmol/L. Areas under the receiver operating characteristic curves of parents for identifying TSB ≥119.7, ≥153.9, ≥205.2, and ≥256.5 µmol/L were 0.967, 0.960, 0.915, and 0.813, respectively, and those of paediatricians were 0.966, 0.961, 0.926 and 0.840, respectively. The intraclass correlation coefficient was 0.933 between parents and paediatricians. CONCLUSION: The JCard can be used to classify different levels of bilirubin, but it is less accurate with high bilirubin levels. The JCard diagnostic performance of parents was slightly lower than that of paediatricians.
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Ictericia Neonatal , Anciano , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Bilirrubina , Ictericia Neonatal/diagnóstico , Padres , Estudios ProspectivosRESUMEN
The smart photochromic materials based on polylactic acid (PLA) were prepared by melt-blending and hot-pressing, in which photochromic microcapsules (PM) were used as a functional additive, and poly(vinyl acetate) (PVAc) was introduced into the photochromic PLA blends for the first time to improve their properties. The crystallization and melting behavior, morphology, and photochromic performance of PLA/PVAc/PM blends were characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and spectrophotometer, respectively. The results showed that PVAc significantly improved the photochromic properties of PLA/PM blends. Under 30 s UV irradiation, the blends reached a value of ΔE that could be recognized in 3 s by human eyes. This discriminative ΔE value could be maintained for at least 3 min after removal from UV irradiation. Meanwhile, the blend had outstanding photochromic durability and recyclability. Compared to ΔE for 0.5 h of continuous light irradiation, ΔE for 8 h of continuous light irradiation decreased by only about 1, to 14.1. In 25 cycles of 3 s UV irradiation, the values of ΔE for the first and 25th irradiation were 11.4 and 11.6, respectively. The blend showed different photochromic responses to different light intensities. The ΔE values of 8.6, 14.6, 14.6, and 18.4 for irradiation at 600, 800, 1000, and 1200 W/m2 of solar intensity, respectively.
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Ácido Láctico , Polímeros , Humanos , Polímeros/química , Ácido Láctico/química , Poliésteres/química , Rastreo Diferencial de CalorimetríaRESUMEN
Antibacterial hydrogel wound dressings with adhesive and antioxidant activity are desirable for treating skin injuries in clinical care. Hereby, a series of multifunctional hydrogel wound dressings with high adhesive, self-healing, antioxidant, and antibacterial activity were designed and fabricated using dopamine (DA) and quercetin (QT). The multifunctional hydrogels were constructed by the interpenetrated quaternized chitosan chain segments and polyacrylamide network. The catechol groups on DA, QT, and the quaternary ammonium groups in the hydrogel system endow hydrogels with high strength, excellent adhesion, and self-healing ability. The results confirmed the admirable hemocompatibility and remarkable antibacterial activity of the multifunction hydrogels against Staphylococcus aureus and Escherichia coli. Consequently, multifunction hydrogels with satisfactory adhesive and antibacterial activity are appropriate alternative materials in the fields of tissue adhesive and wound dressing applications.
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Antioxidantes , Quitosano , Adhesivos , Hidrogeles , Cicatrización de Heridas , Antibacterianos , QuercetinaRESUMEN
Apparent temperature is the preferred measure of hotness or coldness expressed to depict the human sense. Spatially explicit measurement of the hourly apparent temperature is essential for capturing the threats to bioclimatic comfort and preventing potential mortality/morbidity risk from heat or cold. However, existing apparent temperature products only provide daily observations at the spatial resolution of several dozen kilometers, resulting in some substantial underestimations for some life-threatening thermal stresses highly localized in space and time. Furthermore, some data-driven models lack mechanical constraints on the turbulent exchange between the surface and the atmosphere, making some unsatisfactory accuracy. Here, we propose Humidex reconstruction model incorporating atmospheric dynamics theory and aerodynamic parameters (i.e., heat and momentum roughness lengths for natural surfaces and three urban canopy geometry parameters for artificial surfaces), capable of developing an hourly dataset at fine-grained spatial resolution (0.01° × 0.01°). In this study, a total of 2952 h in four seasons were selected to test the seasonal performance of this model, taking the Yangtze River Delta as an example. The results show that the Humidex products from this model generally outperform the existing comparable products, with the hourly population root mean square error (RMSE) ranging from 1 to 2 °C in winter and autumn and 2-3 °C in spring and summer. Moreover, the constraint of aerodynamic parameters can reduce RMSE with a significant margin for each season, up to 2 °C, especially in areas with dense woodlands or buildings. In addition, the results demonstrate the excellent performance of this model in capturing short-lived thermal health threats, which are easily overlooked when observed data only provides a daily variation. This indicates that the model can allow researchers and practitioners investigate the fine-grained spatial and temporal evolution of thermal stress and its impact on public health, tourism, learning, and work performance.
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The sluggish ionic transport in thick electrodes and freezing electrolytes has limited electrochemical energy storage devices in lots of harsh environments for practical applications. Here, a 3D-printed proton pseudocapacitor based on high-mass-loading 3D-printed WO3 anodes, Prussian blue analog cathodes, and anti-freezing electrolytes is developed, which can achieve state-of-the-art electrochemical performance at low temperatures. Benefiting from the cross-scale 3D electrode structure using a 3D printing direct ink writing technique, the 3D-printed cathode realizes an ultrahigh areal capacitance of 7.39 F cm-2 at a high areal mass loading of 23.51 mg cm-2 . Moreover, the 3D-printed pseudocapacitor delivers an areal capacitance of 3.44 F cm-2 and excellent areal energy density (1.08 mWh cm-2 ). Owing to the fast ion kinetics in 3D electrodes and the high ionic conductivity of the hybrid electrolyte, the 3D-printed supercapacitor delivers 61.3% of the room-temperature capacitance even at -60 °C. This work provides an effective strategy for the practical applications of energy storage devices with complex physical structure at extreme temperatures.
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Polylactic acid/butenediol vinyl alcohol copolymer (PLA/BVOH) blends with different weight ratios were prepared by melt mixing. PLA and BVOH in PLA/BVOH blends were immiscible while the weak interaction between PLA and BVOH existed. The introduction of BVOH facilitated the crystallization of PLA. Moreover, the crystallization of PLA hindered the crystallization of BVOH. Due to introduction of BVOH, PLA/BVOH blends exhibited shear thinning characteristic except that PLA/BVOH blends with 5-10 % BVOH showed similar rheological property to neat PLA. With the increase of BVOH content, the contact angle of PLA/BVOH blends decreased from 79.75° to 67.33° at 120 s. The hydrophilicity of PLA/BVOH blends was improved. In addition, PLA/BVOH fibers with 5-40 % BVOH and PLA/BVOH/rutin fibers with 3 % rutin were manufactured by melt spinning. The effect of BVOH on the mechanical property of PLA/BVOH fibers was small. However, BVOH improved significantly the rutin release rate and antioxidant properties of PLA/BVOH/rutin fibers.
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Poliésteres , Polímeros , Polímeros/química , Poliésteres/química , Cristalización , Etanol , Compuestos de ViniloRESUMEN
Heatwaves occur frequently in summer, severely harming the natural environment and human society. While a few long-term spatiotemporal heatwave studies have been conducted in China at the grid scale, their shortcomings involve their discrete distribution and poor spatiotemporal continuity. We used daily data from 691 meteorological stations to obtain torridity index (TI) and heatwave index (HWI) datasets (0.01°) in order to evaluate the spatiotemporal distribution of heatwaves in the Chinese mainland for the period of 1990-2019. The results were as follows: (1) The TI values rose but with fluctuations, with the largest increase occurring in North China in July. The areas with hazard levels of medium and above accounted for 22.16% of the total, mainly in the eastern and southern provinces of China, South Tibet, East and South Xinjiang, and Chongqing. (2) The study areas were divided into four categories according to the spatiotemporal distribution of hazards. The "high hazard and rapidly increasing" and "low hazard and continually increasing" areas accounted for 8.71% and 41.33% of the total, respectively. (3) The "ten furnaces" at the top of the provincial capitals were Zhengzhou, Nanchang, Wuhan, Changsha, Shijiazhuang, Nanjing, Hangzhou, Haikou, Chongqing, and Hefei. While the urbanization level and population aging in the developed areas were further increased, the continuously increasing heatwave hazard should be fully considered.
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Pueblos del Este de Asia , Humanos , Estaciones del Año , China/epidemiología , Ciudades , TibetRESUMEN
Antibiotic abuse has posed enormous burdens on patients and healthcare systems. Hence, the design and development of non-antibiotic wound dressings to meet clinical demand are urgently desired. However, there remains one of the impediments to hydrogel wound dressings that integrated with good recoverability, toughness, and excellent antibacterial properties. Herein, a series of semi-interpenetrating network (semi-IPN) hydrogels with exceptional mechanical performance and remarkable antibacterial activity based on quaternized chitosan (QCS) and polyacrylamide (PAM) were developed using a one-pot method. Additionally, the antibacterial activity of semi-IPN hydrogel against S. aureus and E. coli was enhanced by integrating it with quercetin (QT). The semi-IPN hydrogels also exhibited high recoverability and toughness, outstanding liquid absorbability (the swelling ratio reached 565 ± 12 %), and a satisfying water vapor transmission rate. Moreover, the semi-IPN hydrogels presented ideal hemocompatibility and cytocompatibility. These high-elastic hydrogels are promising candidates for potential applications in wound dressing, tissue repair, chronic wound care, as well as other biomedical fields.