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The newly discovered nickelate superconductors so far only exist in epitaxial thin films synthesized by a topotactic reaction with metal hydrides1. This method changes the nickelates from the perovskite to an infinite-layer structure by deintercalation of apical oxygens1-3. Such a chemical reaction may introduce hydrogen (H), influencing the physical properties of the end materials4-9. Unfortunately, H is insensitive to most characterization techniques and is difficult to detect because of its light weight. Here, in optimally Sr doped Nd0.8Sr0.2NiO2H epitaxial films, secondary-ion mass spectroscopy shows abundant H existing in the form of Nd0.8Sr0.2NiO2Hx (x â 0.2-0.5). Zero resistivity is found within a very narrow H-doping window of 0.22 ≤ x ≤ 0.28, showing unequivocally the critical role of H in superconductivity. Resonant inelastic X-ray scattering demonstrates the existence of itinerant interstitial s (IIS) orbitals originating from apical oxygen deintercalation. Density functional theory calculations show that electronegative H- occupies the apical oxygen sites annihilating IIS orbitals, reducing the IIS-Ni 3d orbital hybridization. This leads the electronic structure of H-doped Nd0.8Sr0.2NiO2Hx to be more two-dimensional-like, which might be relevant for the observed superconductivity. We highlight that H is an important ingredient for superconductivity in epitaxial infinite-layer nickelates.
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The bulk photovoltaic effect (BPVE) offers an interesting approach to generate a steady photocurrent in a single-phase material under homogeneous illumination, and it has been extensively investigated in ferroelectrics exhibiting spontaneous polarization that breaks inversion symmetry. Flexoelectricity breaks inversion symmetry via a strain gradient in the otherwise nonpolar materials, enabling manipulation of ferroelectric order without an electric field. Combining these two effects, we demonstrate active mechanical control of BPVE in suspended 2-dimensional CuInP2S6 (CIPS) that is ferroelectric yet sensitive to electric field, which enables practical photodetection with an order of magnitude enhancement in performance. The suspended CIPS exhibits a 20-fold increase in photocurrent, which can be continuously modulated by either mechanical force or light polarization. The flexoelectrically engineered photodetection device, activated by air pressure and without any optimization, possesses a responsivity of 2.45 × 10-2 A/W and a detectivity of 1.73 × 1011 jones, which are superior to those of ferroelectric-based photodetection and comparable to those of the commercial Si photodiode.
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Poor mass transfer behavior and inherent activity limit the efficiency of traditional catalysts in electrocatalyzing carbon dioxide reduction reactions. However, the development of novel nanomaterials provides new strategies to solve the above problems. Herein, we propose novel single-metal atom catalysts, namely diamane-based electrocatalysts doped with Cu, Fe, and Ni, explored through density functional theory (DFT) calculations. We thoroughly investigated the doping pattern and energetics for different dopants. Furthermore, we systematically investigated the conversion process of CO2 to C1 or C2+ products, utilizing the free energy analysis of reaction pathways. Our results reveal that dopants could only be introduced into diamane following a specific pattern. Dopants significantly enhance the CO2 adsorption ability of diamane, with Fe and Ni proving notably more effective than Cu. After CO2 adsorption, Cu- and Fe-doped diamane prefer to catalyze CO2RR, while Ni-doped diamane favors hydrogen evolution reaction (HER). The C-C coupling reaction on Cu-hollow diamane, Cu-bridge diamane, and Fe-hollow diamane tends to be from C2+ products. Among all examined catalysts, Cu-hollow diamane shows better electro-catalytic performance. Our study demonstrates the feasibility of and contributes to the development of diamane-based electro-catalysts for CO2RR.
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Eltrombopag combined with immunosuppressive therapy (IST) was superior to IST alone for severe aplastic anemia (SAA) in the previous studies. But in China, horse antithymocyte globulin (hATG) is not available, instead, we use rabbit ATG (rATG). Here, we compared the efficacy and safety of IST (rATG combined with cyclosporine) combined with or without eltrombopag for the first-line treatment of SAA and very severe aplastic anemia (VSAA). A total of 371 patients in ten institutions in China from April 1, 2017 to December 1, 2022 were enrolled. The overall response (OR) rate at 3 months (54.2% vs. 41%; P = 0.046), the complete response (CR) (31.3% vs. 19.4%; P = 0.041) and OR (78.3% vs. 51.1%; P < 0.0001) rates at 6 months were significantly higher with IST combined with eltrombopag than with IST alone in SAA patients. While in VSAA patients, the addition of eltrombopag to IST only increased the CR rate at 6 months (29.8% vs. 9.43%; P = 0.010). Liver injury increased significantly in groups treated with IST combined with eltrombopag (P < 0.05). Serious treatment-related toxicities were similar (P > 0.05). In patients with SAA, 3-year failure-free survival (FFS) of eltrombopag combined with IST group was significantly higher than that of IST group (70.7 ± 5.3% vs. 50.3 ± 3.9%; P = 0.007). In patients with VSAA, the addition of eltrombopag significantly improved 3-year overall survival (OS) (82.2 ± 5.7% vs. 57.3 ± 7.2%; P = 0.020). Our findings suggested that IST combined with eltrombopag could improve the hematological recovery of newly diagnosed SAA without increasing severe toxicities. But in VSAA, the addition of eltrombopag seemed to show no other improvement to efficacy except the CR rate at 6 months.
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Anemia Aplástica , Soro Antilinfocitário , Benzoatos , Hidrazinas , Imunossupressores , Pirazóis , Anemia Aplástica/tratamento farmacológico , Anemia Aplástica/mortalidade , Benzoatos/uso terapêutico , Pirazóis/uso terapêutico , Pirazóis/efeitos adversos , Humanos , Hidrazinas/uso terapêutico , Hidrazinas/administração & dosagem , Hidrazinas/efeitos adversos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adolescente , Imunossupressores/uso terapêutico , Soro Antilinfocitário/uso terapêutico , Soro Antilinfocitário/administração & dosagem , Adulto Jovem , Idoso , Estudos Retrospectivos , Quimioterapia Combinada , Criança , Resultado do Tratamento , Índice de Gravidade de Doença , Pré-Escolar , Ciclosporina/uso terapêutico , Ciclosporina/administração & dosagem , China/epidemiologia , Taxa de SobrevidaRESUMO
BACKGROUND: The incidence of stroke in China ranks first in the world and is the leading cause of death and disability in adults. Urinary incontinence is an independent risk factor leading to poor prognosis of stroke. However, studies on the incidence of urinary incontinence in stroke patients and its influencing factors are different, fluctuate greatly, and there is no unified basis. OBJECTIVE: To quantitatively analyze the incidence of urinary incontinence in stroke patients and its related influencing factors, and further make public health strategic decisions to reduce the occurrence of adverse outcomes. METHODS: Computer searches were conducted in PubMed, Medline, Web of Science, Cochrane Library, Embase, CLNAHL Complete, China National Knowledge Infrastructure (CNKI), Chinese Biomedical database(CBM), Wan Fang Database, VIP Database, observational studies such as cohort studies, case-control studies or cross-sectional studies on the incidence or influencing factors of urinary incontinence in stroke patients from the establishment of the database to the publication in August 2023. Studies selection, quality evaluation and data extraction were conducted independently by two researchers according to the established search strategy. Stata 14.0 statistical software was used for meta-analysis. RESULTS: A total of 21 manuscripts were included, with a cumulative sample size of 7327 cases, including 2887 patients with urinary incontinence. Meta-analysis results showed that the incidence of urinary incontinence in stroke patients was 38% [95% confidence interval (34%, 41%)], including married patients and lacunar infarction were the protective factors for urinary incontinence in stroke patients, while age, chaperone, low educational level, chronic cough, lesion sites (parietal lobe, frontal lobe, and temporal lobe), stroke type (cerebral hemorrhage, subarachnoid hemorrhage and cerebral hemorrhage complicated with subarachnoid hemorrhage), dysfunction (aphasia dyslexia, dysphagia, eye movement abnormalities, leg muscle disorders), post-stroke depression, the higher the NIHSS score, the lower the Bachmann index (BI) score, OCSP classification (total anterior circulation infarction) and other 11 items were risk factors for urinary incontinence in stroke patients. CONCLUSION: The incidence of urinary incontinence in stroke patients is 38%. Marriage and lacunar infarction are the protective factors of urinary incontinence. Age, carer, low educational level, chronic cough, lesion site (parietal, frontal and temporal lobes), stroke type (cerebral hemorrhage, subarachnoid hemorrhage, cerebral hemorrhage combined with subarachnoid hemorrhage), dysfunction (aphasia and dysarthria syndrome, dysphagia, eye movement abnormalities, leg muscle disorders), post-stroke depression, and higher NIHSS score, Lower BI score and OCSP classification (total anterior circulation infarction) were risk factors for urinary incontinence in stroke patients.
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Acidente Vascular Cerebral , Incontinência Urinária , Humanos , Incontinência Urinária/epidemiologia , Incontinência Urinária/fisiopatologia , Incontinência Urinária/etiologia , Incidência , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , China/epidemiologiaRESUMO
BACKGROUND: Evidence regarding the relationship between fasting blood glucose (FBG) and suicide attempts (SA) in patients with major depressive disorder (MDD) was limited. Therefore, the objective of this research was to investigate whether FBG was independently related to SA in Chinese patients with first-episode drug-naïve (FEDN) MDD after adjusting for other covariates. METHODS: The present study was a cross-sectional study. A total of 1718 participants (average age: 34.9 ± 12.4 years, 65.8% females) with FEDN MDD were involved in a hospital in China from September 2016 to December 2018. Multiple logistic regression analysis and smooth curve fitting were used to estimate the association between FBG and the risk of SA. The threshold effect was examined by the two-piecewise linear regression model. Interaction and stratified analyses were conducted according to sex, education, marital status, comorbid anxiety, and psychotic symptoms. RESULTS: The prevalence of SA in patients with FEDN MDD was 20.1%. The result of fully adjusted binary logistic regression showed FBG was positively associated with the risk of SA (odds ratio (OR) = 1.62, 95% CI: 1.13-2.32). Smoothing plots also revealed a nonlinear relationship between FBG and SA, with the inflection point of FBG being 5.34 mmol/l. The effect sizes and the confidence intervals on the left and right sides of the inflection point were 0.53 (0.32-0.88, P = 0.014) and 1.48 (1.04-2.10, P = 0.030), respectively. CONCLUSIONS: A U-shaped relationship between FBG and SA in FEDN MDD patients was found, with the lowest risk of SA at a FBG of 5.34 mmol/l, indicating that both the lower and higher FBG levels may lead to an increased risk of SA.
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Glicemia , Transtorno Depressivo Maior , Tentativa de Suicídio , Humanos , Feminino , Masculino , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/epidemiologia , Adulto , Estudos Transversais , Tentativa de Suicídio/estatística & dados numéricos , Tentativa de Suicídio/psicologia , China/epidemiologia , Glicemia/análise , Pessoa de Meia-Idade , Jejum/sangue , Adulto Jovem , Fatores de Risco , Prevalência , População do Leste AsiáticoRESUMO
PURPOSE: Hirschsprung's disease (HSCR) is the leading cause of neonatal functional intestinal obstruction, which has been identified in many familial cases. HSCR, a multifactorial disorder of enteric nervous system (ENS) development, is associated with at least 24 genes and seven chromosomal loci, with RET and EDNRB as its major genes. We present a genetic investigation of familial HSCR to clarify the genotype-phenotype relationship. METHODS: We performed whole exome sequencing (WES) on Illumina HiSeq X Ten platform to investigate genetic backgrounds of core family members, and identified the possibly harmful mutation genes. Mutation carriers and pedigree relatives were validated by Sanger sequencing for evaluating the gene penetrance. RESULTS: Four familial cases showed potential disease-relative variants in EDNRB and RET gene, accounting for all detection rate of 57.1%. Three familial cases exhibited strong pathogenic variants as frameshift or missense mutations in EDNRB gene. A novel c.367delinsTT mutation of EDNRB was identified in one family member. The other two EDNRB mutations, c.553G>A in family 2 and c.877delinsTT in family 5, have been reported in previous literatures. The penetrance of EDNRB variants was 33-50% according mutation carries. In family 6, the RET c.1858T>C (C620R) point mutation has previously been reported to cause HSCR, with 28.5% penetrance. CONCLUSION: We identified a novel EDNRB (deleted C and inserted TT) mutation in this study using WES. Heterozygote variations in EDNRB gene were significantly enriched in three families and RET mutations were identified in one family. EDNRB variants showed an overall higher incidence and penetrance than RET in southern Chinese families cases.
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Doença de Hirschsprung , Obstrução Intestinal , Receptor de Endotelina B , Humanos , Recém-Nascido , China/epidemiologia , Doença de Hirschsprung/genética , Incidência , Mutação , Receptor de Endotelina B/genéticaRESUMO
In this study, two previously undescribed nitrogen-containing compounds, penisimplicins A (1) and B (2), were isolated from Penicillium simplicissimum JXCC5. The structures of 1 and 2 were elucidated on the basis of comprehensive spectroscopic data analysis, including 1D and 2D NMR and HRESIMS data. The absolute configuration of 2 was determined by Marfey's method, ECD calculation, and DP4+ analysis. Both structures of 1 and 2 feature an unprecedented manner of amino acid-derivatives attaching to a polyketide moiety by C-C bond. The postulated biosynthetic pathways for 1 and 2 were discussed. Additionally, compound 1 exhibited significant acetylcholinesterase inhibitory activity, with IC50 values of 6.35 µM.
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Alcaloides , Penicillium , Policetídeos , Estrutura Molecular , Policetídeos/química , Acetilcolinesterase/metabolismo , Penicillium/química , Peptídeos/metabolismo , Alcaloides/químicaRESUMO
Weak adsorption of gas reactants and strong binding of intermediates present a significant challenge for most transition metal oxides, particularly in the realm of CO2 photoreduction. Herein, we demonstrate that the adsorption can be fine-tuned by phase engineering of oxide catalysts. An oxygen vacancy mediated topological phase transition in Ni-Co oxide nanowires, supported on a hierarchical graphene aerogel (GA), is observed from a spinel phase to a rock-salt phase. Such in situ phase transition empowers the Ni-Co oxide catalyst with a strong internal electric field and the attainment of abundant oxygen vacancies. Among a series of catalysts, the in situ transformed spinel/rock-salt heterojunction supported on GA stands out for an exceptional photocatalytic CO2 reduction activity and selectivity, yielding an impressive CO production rate of 12.5â mmol g-1 h-1 and high selectivity of 96.5 %. This remarkable performance is a result of the robust interfacial coupling between two topological phases that optimizes the electronic structures through directional charge transfer across interfaces. The phase transition process induces more Co2+ in octahedral site, which can effectively enhance the Co-O covalency. This synergistic effect balances the surface activation of CO2 molecules and desorption of reaction intermediates, thereby lowering the energetic barrier of the rate-limiting step.
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Giant molecular acceptors (GMAs) are typically designed through the conjugated linking of individual small molecule acceptors (SMAs). This design imparts an extended molecular size, elevating the glass transition temperature (Tg) relative to their SMA counterparts. Consequently, it effectively suppresses the thermodynamic relaxation of the acceptor component when blended with polymer donors to construct stable polymer solar cells (PSCs). Despite their merits, the optimization of their chemical structure for further enhancing of device performance remains challenge. Different from previous reports utilizing p-type linkers, here, we explore an n-type linker, specifically the benzothiadiazole unit, to dimerize the SMA units via a click-like Knoevenagel condensation, affording BT-DL. In comparison with B-DL with a benzene linkage, BT-DL exhibits significantly stronger intramolecular super-exchange coupling, a desirable property for the acceptor component. Furthermore, BT-DL demonstrates a higher film absorption coefficient, redshifted absorption, larger crystalline coherence, and higher electron mobility. These inherent advantages of BT-DL translate into a higher power conversion efficiency of 18.49 % in PSCs, a substantial improvement over the 9.17 % efficiency observed in corresponding devices with B-DL as the acceptor. Notably, the BT-DL based device exhibits exceptional stability, retaining over 90 % of its initial efficiency even after enduring 1000â hours of thermal stress at 90 °C. This work provides a cost-effective approach to the synthesis of n-type linker-dimerized GMAs, and highlight their potential advantage in enhancing intramolecular coupling for more efficient and durable photovoltaic technologies.
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Polymer solar cells (PSCs) rely on a blend of small molecular acceptors (SMAs) with polymer donors, where thermodynamic relaxation of SMAs poses critical concerns on operational stability. To tackle this issue, tethered SMAs, wherein multiple SMA-subunits are connected to the aromatic-core via flexible chains, are proposed. This design aims to an elevated glass transition temperature (Tg) for a dynamical control. However, attaining an elevated Tg value with additional SMA subunits introduces complexity to the molecular packing, posing a significant challenge in realizing both high stability and power conversion efficiency (PCE). In this study, we initiate isomer engineering on the benzene-carboxylate core and find that meta-positioned dimeric BDY-ß exhibits more favorable molecular packing compared to its para-positioned counterpart, BDY-α. With this encouraging result, we expand our approach by introducing an additional SMA unit onto the aromatic core of BDY-ß, maintaining a meta-position relative to each SMA unit location in the tethered acceptor. This systematic aromatic-core engineering results in a star-shaped C3h-positioned molecular geometry. The supramolecular interactions of SMA units in the trimer contribute to enhancements in Tg value, crystallinity, and a red-shifted absorption compared to dimers. These characteristics result in a noteworthy increase in PCE to 18.24 %, coupled with a remarkable short-circuit current density of 27.06â mA cm-2. More significantly, the trimer-based devices delivered an excellent thermal stability with over 95 % of their initial efficiency after 1200â h thermal degradation. Our findings underscore the promise and feasibility of tethered trimeric structures in achieving highly ordered aggregation behavior and increased Tg value in PSCs, simultaneously improving in device efficiency and thermal stability.
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Glucose monitoring is essential to evaluate the degree of glucose metabolism disorders. The enzymatic determination has been the most widely used method in glucose detection because of its high efficiency, accuracy, and sensitivity. Noble metal nanomaterials (NMs, i.e., Au, Ag, Pt, and Pd), inheriting their excellent electronic, optical, and enzyme-like properties, are classified as noble metal nanozymes (NMNZs). As the NMNZs are often involved in two series of reactions, the oxidation of glucose and the chromogenic reaction of peroxide, here the chemical mechanism by employing NMNZs with glucose oxidase (GOx) and peroxidase (POD) mimicking activities is briefly summarized first. Subsequently, the regulation strategies of the GOx-like, POD-like and tandem enzyme-like activities of NMNZs are presented in detail, including the materials, size, morphology, composition, and the reaction condition of the representative NMs. In addition, in order to further mimic the enantioselectivity of enzyme, the design of NMNZs with enantioselective recognition of d-glucose and l-glucose by using different chiral compounds (DNA, amino acids, and cyclodextrins) and molecular imprinting is further described in this review. Finally, the feasible solutions to the existing challenges and a vision for future development possibilities are discussed.
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Automonitorização da Glicemia , Glucose , Estereoisomerismo , Glicemia , Metais , Glucose Oxidase/metabolismo , AntioxidantesRESUMO
Sepsis-associated encephalopathy (SAE) is a serious and common complication of sepsis. To study the ferroptosis in the pathogenesis of SAE and demonstrate the protection effect of ferroptosis resistance, cognitive function, neurological deficits, blood-brain barrier integrity and neuroinflammation were detected. SAE model was established by cecal ligation and puncture (CLP) in mice and an in vitro model was created by introducing LPS to HT22 cells. Ferroptosis inducer Fe-citrate (Fe) and ferroptosis inhibitor ferrostatin-1 (Fer-1) was post-treated in the models, respectively. SAE caused ferroptosis, as evidenced by an increase in reactive oxygen species (ROS), iron content and malondialdehyde (MDA) and a decrease in glutathione (GSH) level, as well as changes in the expression of ferroptosis-related proteins as acyl-CoA synthetase long-chain family member 4 (ACSL4), glutathione peroxidase 4 (GPX4), and cystine-glutamate antiporter (SLC7A11), and harmed mitochondrial function. In contrast, inhibiting ferroptosis with Fer-1 attenuated ferroptosis. Meanwhile, Fer-1 attenuated neurologic severity score, learning and memory impairment, Fluoro-Jade C (FJC) staining, and decreased Evans Blue (EB) extravasation, microglia activation and TNF-α and IL-1ß production following SAE. The benefit of Fer-1 was diminished by ferroptosis inducer Fe. In addition, Fer-1 up-regulated the nuclear factor erythroid-2-related factor 2 (Nrf2)/ heme oxygenase-1(HO-1) signaling axis both in vivo and in vitro. In conclusion, our study revealed that Fer-1 might inhibit feroptosis in neurons by triggering the Nrf2/OH-1 pathway, thereby providing a therapeutic solution for SAE.
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Ferroptose , Encefalopatia Associada a Sepse , Animais , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Cicloexilaminas/farmacologiaRESUMO
BACKGROUND: Metastasis is a key feature of malignant tumors and significantly contributes to their high mortality, particularly in hepatocellular carcinoma (HCC). Therefore, it is imperative to explore the mechanism of tumor metastasis. Recently, tumor-associated macrophages (TAMs) have been demonstrated to promote tumor progression, while TAM-derived molecules involved in HCC metastasis warrant further investigation. METHODS: THP-1 was treated with IL-4 (Interleukin-4) and IL-13 (Interleukin-13) for M2 polarized macrophages. Exosomes derived from M2 macrophages were characterized. Then, HCC cells or human umbilical vein endothelial cells (HUVECs) were co-cultured with M2 macrophages or treated with M2 macrophage-secreted exosomes. Next, Transwell®, Scratch assay, tube formation, and endothelial permeability assays were performed. Moreover, RT-PCR, western blotting, immunofluorescence, and ELISA were used to assess mRNA and protein expression levels. Finally, the miRNA expression profiles of exosomes derived from M2 and M0 macrophages were analyzed. RESULTS: M2 macrophage infiltration was correlated with metastasis and a poor prognosis in HCC patients. M2-derived exosomes were absorbed by HCC and HUVEC cells and promoted the epithelial-mesenchymal transition (EMT), vascular permeability, and angiogenesis. Notably, MiR-23a-3p levels were significantly higher in M2-derived exosomes and hnRNPA1 mediated miR-23a-3p packaging into exosomes. Phosphatase and tensin homolog (PTEN) and tight junction protein 1 (TJP1) were the targets of miR-23a-3p, as confirmed by luciferase reporter assays. Lastly, HCC cells co-cultured with M2-derived exosomes secreted more GM-CSF, VEGF, G-CSF, MCP-1, and IL-4, which in turn further recruited M2 macrophages. CONCLUSIONS: Our findings suggest that M2 macrophage-derived miR-23a-3p enhances HCC metastasis by promoting EMT and angiogenesis, as well as increasing vascular permeability. Video Abstract.
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Carcinoma Hepatocelular , Exossomos , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Interleucina-4 , Neoplasias Hepáticas/patologia , Permeabilidade Capilar , Exossomos/metabolismo , Células Endoteliais/metabolismo , Linhagem Celular Tumoral , Macrófagos/metabolismoRESUMO
Solar water purification technology is one of the most potent methods to obtain freshwater due to its low cost and non-polluting characteristics. However, the purification efficiency is limited by the high ion concentration, organic pollution, and biological pollution during the actual water purification process. Here, we report a porous hydrogel membrane (Fe/TA-TPAM) for the purification of high ion concentration and contaminated water. The hydrogel membrane exhibits good light absorption and photothermal conversion ability, which shows high evaporation rates (1.4 kg m-2 h-1) and high solar efficiency for seawater. Furthermore, with the introduction of tannic acid (TA) and Ti3C2 MXenes, the Fe/TA-TPAM hydrogel membrane exhibits satisfied purification properties for organic-contaminated and biologically contaminated water. The excellent purification effect of Fe/TA-TPAM under light not only confirms the rationality of the hydrogel porous design and in situ generation of photosensitizer in improving the photothermal performance but also provides a novel strategy for designing advanced photothermal conversion membranes for water purification.
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Gaseous thallium (Tl) pollution events, primarily caused by non-ferrous mineral refineries and fossil fuel combustion, have increased over the past few decades. To prevent gaseous Tl distribution from flue gas, MnO2/CeO2@HKUST-1 (MCH) was synthesized and found to achieve a gaseous Tl(I) removal level of up to 90% at 423 K, a weight hourly space velocity (WHSV) of 2000 h-1/mL with an Mn dose of 10%, maintained over 10 h. The best Mn/Ce ratio was found to be 9:1. To further investigate surface kinetic behavior, four commonly used kinetic models were applied, including the Eley-Rideal (ER) model, Langmuir-Hinshelwood (LH) model, Mars-van Krevelen (MVK) model, and pseudo-first-order (PFO) model. While the ER and LH models had the slightest deviation, the MVK model was the most reliable. The CatMAP software was also used to match the simulation deviation. This work demonstrated the Tl removal mechanism and provided insights into the accuracy of kinetic models on minor-radius heavy metal. Thus, this research may help promote the design of reactors, heavy metal removal rates, and flue gas purification technology selection.
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The issue focuses on physics-informed machine learning and its applications for structural integrity and safety assessment of engineering systems/facilities. Data science and data mining are fields in fast development with a high potential in several engineering research communities; in particular, advances in machine learning (ML) are undoubtedly enabling significant breakthroughs. However, purely ML models do not necessarily carry physical meaning, nor do they generalize well to scenarios on which they have not been trained on. This is an emerging field of research that potentially will raise a huge impact in the future for designing new materials and structures, and then for their proper final assessment. This issue aims to update the current research state of the art, incorporating physics into ML models, and providing tools when dealing with material science, fatigue and fracture, including new and sophisticated algorithms based on ML techniques to treat data in real-time with high accuracy and productivity. This article is part of the theme issue 'Physics-informed machine learning and its structural integrity applications (Part 1)'.
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In the present study, a physics-informed neural network model based on Bayesian hyperparameter optimization is proposed for the prediction of short crack growth paths. A large number of cyclic loadings at a lower amplitude were applied to an α titanium sample by an ultrasonic fatigue machine to ensure a sufficient amount of data for machine learning. The grain size, grain orientation and grain boundary direction on the path, as well as crack growth direction, were selected as feature data for training the prediction model. The optimizations of the size ratio and the angle operation were conducted to compare different data processing methods, respectively. After evaluation, eventually, a model for predicting crack growth path is obtained with a reliable performance of 10% tolerance on the path angle at each grain boundary. And the prediction effect of the proposed model is better than that of some classic machine learning models and slip trace analysis. This article is part of the theme issue 'Physics-informed machine learning and its structural integrity applications (Part 1)'.
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The development of machine learning (ML) provides a promising solution to guarantee the structural integrity of critical components during service period. However, considering the lack of respect for the underlying physical laws, the data hungry nature and poor extrapolation performance, the further application of pure data-driven methods in structural integrity is challenged. An emerging ML paradigm, physics-informed machine learning (PIML), attempts to overcome these limitations by embedding physical information into ML models. This paper discusses different ways of embedding physical information into ML and reviews the developments of PIML in structural integrity including failure mechanism modelling and prognostic and health management (PHM). The exploration of the application of PIML to structural integrity demonstrates the potential of PIML for improving consistency with prior knowledge, extrapolation performance, prediction accuracy, interpretability and computational efficiency and reducing dependence on training data. The analysis and findings of this work outline the limitations at this stage and provide some potential research direction of PIML to develop advanced PIML for ensuring structural integrity of engineering systems/facilities. This article is part of the theme issue 'Physics-informed machine learning and its structural integrity applications (Part 1)'.
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Elementally-doped graphene demonstrates remarkable gas sensing capabilities as a novel 2D sensor material. In this study, we employed density functional theory calculations, we investigated the impact of various dopants on the BTEX (benzene, toluene, ethylbenzene, and xylene) sensing performance of graphene. Through the systematic analysis of electronic structures and sensitivity, we observed that both the doping method and dopant type significantly influence the interactions between graphene and BTEX molecules. Out of the 22 different elemental doped graphenes studied, N-, O-, and Pd-doped graphenes emerged as promising candidates for BTEX sensor materials. Graphene with N-doping exhibited relatively higher sensitivity towards toluene, ethylbenzene, and xylene compared to O- and Pd-doped graphenes. However, it demonstrated low sensitivity towards benzene. On the other hand, O-doped graphene displayed excellent selectivity for ethylbenzene over the other three gas molecules (benzene, toluene, and xylene). Similarly, Pd-doped graphene also exhibited significant selectivity for ethylbenzene and possessed higher sensitivity than the O-doped graphene. Their distinct characteristics and sensitivities make them potential candidates for future applications in gas sensing technology.