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Ternary-phase CuWO4oxide with an electronic band gap of 2.2-2.4 eV is a potential candidate photoanode material for photoelectrochemical (PEC) water splitting. Herein, we present an efficient method to prepare CuWO4film photoanode by combining hydrothermal method and hybrid microwave annealing (HMA) process. In comparison with conventional thermal annealing (CTA), HMA can achieve CuWO4thin film within minutes by using SiC susceptor. When the CuWO4photoanode is prepared by HMA, its PEC water oxidation performance improves from 0.21 to 0.29 mA cm-2at 1.23 VRHEcomparing with the one prepared by CTA. The origin of the enhanced photocurrent was investigated by means of complementary physical characterizations and PEC methods. The results demonstrated that the obtained HMA processed CuWO4photoanode not only exhibited intrinsic porous nanostructures but also abundant surface hydroxyl groups, which facilitated sufficient mass transport and the charge transfer. Our results highlight the application of HMA for the fast fabrication of porous film photo-electrodes without using sacrificial template.
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Heart failure (HF) with preserved ejection fraction (HFpEF) is currently a preeminent challenge for cardiovascular medicine. It has a poor prognosis, increasing mortality, and is escalating in prevalence worldwide. Despite accounting for over 50% of all HF patients, the mechanistic underpinnings driving HFpEF are poorly understood, thus impeding the discovery and development of mechanism-based therapies. HFpEF is a disease syndrome driven by diverse comorbidities, including hypertension, diabetes and obesity, pulmonary hypertension, aging, and atrial fibrillation. There is a lack of high-fidelity animal models that faithfully recapitulate the HFpEF phenotype, owing primarily to the disease heterogeneity, which has hampered our understanding of the complex pathophysiology of HFpEF. This review provides an updated overview of the currently available animal models of HFpEF and discusses their characteristics from the perspective of energy metabolism. Interventional strategies for efficiently utilizing energy substrates in preclinical HFpEF models are also discussed.
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Insuficiência Cardíaca , Hipertensão , Animais , Humanos , Volume Sistólico/fisiologia , Comorbidade , Descoberta de DrogasRESUMO
Atherosclerosis is a common cardiovascular disease closely associated with factors such as hyperlipidaemia and chronic inflammation. Among them, endothelial dysfunction serves as a major predisposing factor. Vascular endothelial dysfunction is manifested by impaired endothelium-dependent vasodilation, enhanced oxidative stress, chronic inflammation, leukocyte adhesion and hyperpermeability, endothelial senescence, and endothelial-mesenchymal transition (EndoMT). Flavonoids are known for their antioxidant activity, eliminating oxidative stress induced by reactive oxygen species (ROS), thereby preventing the oxidation of low-density lipoprotein (LDL) cholesterol, reducing platelet aggregation, alleviating ischemic damage, and improving vascular function. Flavonoids have also been shown to possess anti-inflammatory activity and to protect the cardiovascular system. This review focuses on the protective effects of these naturally-occuring bioactive flavonoids against the initiation and progression of atherosclerosis through their effects on endothelial cells including, but not limited to, their antioxidant, anti-inflammatory, anti-thrombotic, and lipid-lowering properties. However, more clinical evidences are still needed to determine the exact role and optimal dosage of these compounds in the treatment of atherosclerosis.
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Energetic coatings have attracted a great deal of interest with respect to their compatibility and high energy and power density. However, their preparation by effective and inexpensive methods remains a challenge. In this work, electrophoretic deposition was investigated for the deposition of an Al/CuO thermite coating as a typical facile effective and controllable method. Given the poor adhesion of the deposited film and the native inert Al2O3 shell on Al limiting energy output, further treatment was conducted by soaking in a Nafion solution, which not only acted as a fluoropolymer binder but also introduced a strong F oxidizer. It is interesting to note that the adhesion level of Al/CuO films was improved greatly from 1B to 4B, which was attributed to Nafion organic network film formation, like a fishing net covering the loose particles in the film. Combustion and energy release were analyzed using a high-speed camera and a differential scanning calorimeter. A combustion rate of ≤3.3 m/s and a heat release of 2429 J/g for Al/NFs/CuO are far superior to those of pristine Al/CuO (1.3 m/s and 841 J/g, respectively). The results show that the excellent combustion and heat release properties of the energetic film system are facilitated by the good combustion-supporting properties of organic molecules and the increase in the film density after organic treatment. The prepared Al/NFs/CuO film was also employed as ignition material to fire B-KNO3 explosive successfully. This study provides a new way to prepare organic-inorganic hybrid energetic films, simultaneously altering the energy release and enhancing the adhesive force. In addition, the Al/NFs/CuO coating also showed considerable potential as an ignition material in microignitors.
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Aromatic imides are a class of attractive organic materials with inherently electroactive groups and large π electron-deficient scaffolds, which hold potential as electrode materials for organic secondary batteries (OSBs). However, the undecorated aromatic imides are usually plagued by low capacity, high solubility in electrolyte, and poor electronic/ionic conductivity. Molecular engineering has been demonstrated to be an effective strategy to address unsatisfying characteristics of the aromatic imides, thereby expanding their scope for applications in OSBs. In this review, the recent research progress in modulation of the capacity, dissolution, and electronic/ionic conductivity of aromatic imides for organic lithium batteries, organic sodium batteries, and redox flow batteries are summarized. In addition, the challenge and prospective of aromatic imides in organic secondary battery applications are also discussed.
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BACKGROUND: The lack of effective means for the early diagnosis of non-small cell lung cancer (NSCLC) is the leading cause of the high mortality of NSCLC. This study aims to evaluate the clinical significance of serum mannan-binding lectin associated serine protease (MASP)-2 and isocitrate dehydrogenase 1 (IDH1) in the early diagnosis of NSCLC. METHODS: The serum levels of MASP-2 and IDH1 were detected in 139 NSCLC patients, 46 patients with benign lung diseases and 61 healthy controls, using an enzyme linked immunosorbent method. The diagnostic significance in NSCLC of the two tumor markers were analyzed by receiver operating characteristic (ROC) curves. In addition, we compared the two markers with the current commonly used tumor marker cytokeratin 19 fragment (Cy¬fra21-1). RESULTS: The serum levels of MASP-2 and IDH1 in the NSCLC patients were significantly higher than those of healthy controls and patients with benign lung diseases. The differences were statistically significant (p < 0.01). The combined sensitivity of MASP-2, IDH1, and Cyfra21-1 in the NSCLC was 68.3%, which was significantly higher than that of the single tumor marker (p < 0.01). The sensitivities of MASP-2 and IDH1 in detecting early NSCLC (stage I and stage II) were 39.0% and 41.5%, which were significantly higher than that of Cyfra21-1 (p < 0.05). The area under the ROC curves (AUCs) of MASP-2 and IDH1 in the diagnosis of NSCLC were 0.621, and 0.840, which were higher than that of Cyfra21-1 (AUC = 0.606). CONCLUSIONS: Serum MASP-2 and IDH1 may be used as potential tumor markers for the auxiliary diagnosis and early diagnosis of NSCLC.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antígenos de Neoplasias , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Detecção Precoce de Câncer , Humanos , Isocitrato Desidrogenase/genética , Queratina-19 , Neoplasias Pulmonares/diagnóstico , Serina Proteases Associadas a Proteína de Ligação a ManoseRESUMO
BACKGROUND: Studies have shown that miRNA (miR) can be stably detected in serum, and aberrant expression of various miRNAs has shown diagnostic value in non-small cell lung cancer (NSCLC) patients. However, the role of miRNA in the context of prognosis has not been extensively investigated. Our previous study reported that miR-22, miR-125b, and miR-15b in serum had potential for use as tumor markers for auxiliary diagnosing of NSCLC. Therefore, the objective of this study was to detect the levels of miR-22, miR-125b, and miR-15b in serum from NSCLC patients and explore the potential prognostic significance of the three selected miRNAs. METHODS: The relative expression of miR-22, miR-125b, and miR-15b in 74 patients with advanced NSCLC in pre- and post-chemotherapy were detected by real-time quantitative polymerase chain reaction. RESULTS: Serum level of miR-125b significantly decreased after chemotherapy (p < 0.05) and the levels of miR-15b significantly increased (p < 0.01), while there was no change in the level of serum miR-22 (Z = 0.716, p > 0.05). Compared with pre-chemotherapy, serum miR-125b expression in advanced NSCLC patients of responders (CR + PR) were significantly decreased post-chemotherapy (p < 0.05); serum miR-15b expression in advanced NSCLC patients of responders (CR + PR) were increased (p < 0.01). The chemotherapy sensitivity of advanced NSCLC patients with high expression of miR-125b was lower than that of NSCLC patients with low expression (p < 0.05). The chemotherapy sensitivity of advanced NSCLC patients with high expression of miR-15b was higher than that of NSCLC patients with low expression (p < 0.05). High levels of serum miR-125b and low levels of serum miR-15b were related to poor overall survival (p < 0.05). CONCLUSIONS: The serum levels of miR-125b and miR-15b in advanced NSCLC patients were changed pre- and post-chemotherapy and these changes were associated with chemotherapeutic response. Serum miR-125b and miR-15b have certain potential clinical value for chemotherapeutic response in advanced NSCLC. The serum levels of miR-125b and miR-15b in patients with advanced NSCLC before treatment may be used to estimate the overall survival.
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs/sangue , Biomarcadores Farmacológicos/sangue , Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Monitoramento de Medicamentos/métodos , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Análise de SobrevidaRESUMO
RATIONALE: Endothelial dysfunction plays an integral role in pulmonary hypertension (PH). AMPK (AMP-activated protein kinase) and ACE2 (angiotensin-converting enzyme 2) are crucial in endothelial homeostasis. The mechanism by which AMPK regulates ACE2 in the pulmonary endothelium and its protective role in PH remain elusive. OBJECTIVES: We investigated the role of AMPK phosphorylation of ACE2 Ser680 in ACE2 stability and deciphered the functional consequences of this post-translational modification of ACE2 in endothelial homeostasis and PH. METHODS: Bioinformatics prediction, kinase assay, and antibody against phospho-ACE2 Ser680 (p-ACE2 S680) were used to investigate AMPK phosphorylation of ACE2 Ser680 in endothelial cells. Using CRISPR-Cas9 genomic editing, we created gain-of-function ACE2 S680D knock-in and loss-of-function ACE2 knockout (ACE2-/-) mouse lines to address the involvement of p-ACE2 S680 and ACE2 in PH. The AMPK-p-ACE2 S680 axis was also validated in lung tissue from humans with idiopathic pulmonary arterial hypertension. MEASUREMENTS AND MAIN RESULTS: Phosphorylation of ACE2 by AMPK enhanced the stability of ACE2, which increased Ang (angiotensin) 1-7 and endothelial nitric oxide synthase-derived NO bioavailability. ACE2 S680D knock-in mice were resistant to PH as compared with wild-type littermates. In contrast, ACE2-knockout mice exacerbated PH, a similar phenotype found in mice with endothelial cell-specific deletion of AMPKα2. Consistently, the concentrations of phosphorylated AMPK, p-ACE2 S680, and ACE2 were decreased in human lungs with idiopathic pulmonary arterial hypertension. CONCLUSIONS: Impaired phosphorylation of ACE2 Ser680 by AMPK in pulmonary endothelium leads to a labile ACE2 and hence is associated with the pathogenesis of PH. Thus, AMPK regulation of the vasoprotective ACE2 is a potential target for PH treatment.
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Proteínas Quinases Ativadas por AMP/metabolismo , Endotélio Vascular/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Peptidil Dipeptidase A/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , Modelos Animais de Doenças , Endotélio Vascular/enzimologia , Humanos , Hipertensão Pulmonar/enzimologia , Pulmão/enzimologia , Pulmão/fisiopatologia , Camundongos , Camundongos Knockout , Ratos , Ratos Sprague-DawleyRESUMO
CKD is an independent risk factor for cardiovascular disease (CVD). The accumulation of uremic toxins in CKD induces oxidative stress and endothelial dysfunction. MicroRNA-92a (miR-92a) is induced by oxidative stress in endothelial cells (ECs) and involved in angiogenesis and atherosclerosis. We investigated a role for oxidative stress-responsive miR-92a in CKD. Our study of patients at three clinical sites showed increased serum miR-92a level with decreased kidney function. In cultured ECs, human CKD serum or uremic toxins (such as indoxyl sulfate), compared with non-CKD serum, induced the levels of miR-92a and suppressed the expression of miR-92a targets, including key endothelial-protective molecules. The antioxidant N-acetylcysteine inhibited these vasculopathic properties. In rats, adenine-induced CKD associated with increased levels of miR-92a in aortas, serum, and CD144+ endothelial microparticles. Furthermore, CD144+ microparticles from human uremic serum contained more miR-92a than those from control serum. Additional analysis showed a positive correlation between serum levels of miR-92a and indoxyl sulfate in a cohort of patients with ESRD undergoing hemodialysis. Collectively, our findings suggest that the uremic toxins accumulated in CKD can upregulate miR-92a in ECs, which impairs EC function and predisposes patients to CVD.
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Células Endoteliais/fisiologia , MicroRNAs/fisiologia , Insuficiência Renal Crônica/fisiopatologia , Animais , Feminino , Humanos , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Ratos , Ratos Wistar , Insuficiência Renal Crônica/sangueRESUMO
BACKGROUND: The lack of effective means for the early diagnosis of non-small cell lung cancer (NSCLC) is the leading cause of the high mortality associated with this form of lung cancer. This study aims to explore the potential significance of serum miRNA in the auxiliary diagnosis of NSCLC. METHODS: The relative serum levels of 10 miRNAs in 120 patients with NSCLC, 45 patients with benign lung diseases, and 45 healthy controls were detected using real-time quantitative polymerase chain reaction (PCR). The receiver operating characteristic (ROC) curves were then used to analyze the significance of the expression of these 10 miRNAs in the diagnosis of NSCLC, as well as to compare them with the current commonly used tumor marker carcinoembryonic antigen (CEA). RESULTS: The serum levels of miR-125b and miR-22 in the NSCLC patients were significantly higher than those in the other two groups (p < 0.05), but the serum expression of miR-15b in the NSCLC patients was significantly lower than that in the other two groups (p < 0.01). The sensitivities of serum miR-22 and miR-15b in detecting early NSCLC (stage I + II) were significantly higher than that of CEA (p < 0.05). Area under the curves (AUCs) of serum miR-22, miR-125b, and miR-15b in the diagnosis of NSCLC were 0.725, 0.704, and 0.619, respectively, and the diagnostic significance of these three serum miRNAs for NSCLC was higher than that of serum CEA (AUC = 0.594). CONCLUSIONS: Serum miRNAs have potential as NSCLC-screening tumor markers, and serum miR-22 and miR15b might be used as reference indexes for the early diagnosis of NSCLC in the future.
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Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , MicroRNA Circulante/sangue , Neoplasias Pulmonares/diagnóstico , Adulto , Idoso , Área Sob a Curva , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Casos e Controles , MicroRNA Circulante/genética , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , MicroRNAs/sangue , MicroRNAs/genética , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Many tumor markers have been analyzed for applications in diagnosis, prognosis, and monitoring of cancer. Currently chemotherapy is routinely performed for patients with non-small cell lung cancer (NSCLC). The purpose of this study was to examine the serum tumor biomarker of cytokeratin (CK)-3A9 level in patients with NSCLC and its potential correlation with chemotherapeutic response. METHODS: The serum samples of 196 NSCLC patients, 84 healthy controls, and 87 benign lung disease patients were provided for measurement of CK-3A9 and carcinoembryonic antigen (CEA). Serum CK-3A9 concentration was examined using a chemoluminescent method. The potential correlation between serum CK18-3A9 concentration and chemotherapeutic response was analyzed in 124 patients with advanced NSCLC (stages III and IV). RESULTS: The serum CK-3A9 levels in NSCLC patients pre-chemotherapy were significantly higher than those of healthy controls and benign lung disease patients (p < 0.01). CK-3A9 was related to Union for International Cancer Control (UICC) stages (p < 0.01) and histological classification (p < 0.05), but not related to age, gender, smoking status, and chemotherapy regimen (all p > 0.05). The testing results of serum CK-3A9 levels showed a higher sensitivity than that for CEA (48.2% and 39.5%, respectively). The chemotherapeutic response in the 124 patients with advanced NSCLC included 0 complete response (CR), 50 partial response (PR), 65 no change (NC), and 9 progression disease (PD). Post-chemotherapy CK-3A9 levels were significantly decreased compared to pre-chemotherapy (p < 0.05). The serum CK-3A9 levels in patients who achieved PR declined significantly compared to those who did not respond (SD + PD) after 2 cycles chemotherapy (p < 0.05). CONCLUSIONS: CK-3A9 appeared to be a new biomarker for reliable, cost-effective prediction of the efficacy of chemotherapy in patients with advanced NSCLC, although the results should be confirmed in larger studies.
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Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/uso terapêutico , Queratinas/sangue , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Biomarcadores/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Pulmonares/sangue , Masculino , Pessoa de Meia-IdadeRESUMO
Nonalcoholic fatty liver disease (NAFLD) encompasses a disease continuum from simple steatosis to nonalcoholic steatohepatitis (NASH). However, there are currently no approved pharmacotherapies for NAFLD, although several drugs are in advanced stages of clinical development. Because of the complex pathophysiology and heterogeneity of NAFLD, the identification of potential therapeutic targets is clinically important. Here, we demonstrated that tripartite motif 56 (TRIM56) protein abundance was markedly downregulated in the livers of individuals with NAFLD and of mice fed a high-fat diet. Hepatocyte-specific ablation of TRIM56 exacerbated the progression of NAFLD, while hepatic TRIM56 overexpression suppressed it. Integrative analyses of interactome and transcriptome profiling revealed a pivotal role of TRIM56 in lipid metabolism and identified the lipogenesis factor fatty acid synthase (FASN) as a direct binding partner of TRIM56. TRIM56 directly interacted with FASN and triggered its K48-linked ubiquitination-dependent degradation. Finally, using artificial intelligence-based virtual screening, we discovered an orally bioavailable small-molecule inhibitor of FASN (named FASstatin) that potentiates TRIM56-mediated FASN ubiquitination. Therapeutic administration of FASstatin improved NAFLD and NASH pathologies in mice with an optimal safety, tolerability, and pharmacokinetics profile. Our findings provide proof of concept that targeting the TRIM56/FASN axis in hepatocytes may offer potential therapeutic avenues to treat NAFLD.
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Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Inteligência Artificial , Dieta Hiperlipídica/efeitos adversos , Ácido Graxo Sintases/genética , Hepatopatia Gordurosa não Alcoólica/genéticaRESUMO
BACKGROUND: Many tumor markers are analyzed for usefulness in diagnosis, prognosis, and monitoring. The purpose of this study was to evaluate a new type of tumor biomarker, cytokeratin (CK)-2G2, in serum for the early diagnosis, confirmative diagnosis as well as assessment of treatments of non-small cell lung cancer (NSCLC). METHODS: Use a chemiluminescent method to examine the serum CK-2G2 levels in 100 patients with non-malignant lung diseases and 100 cases from the healthy population, as well as 124 cases of NSCLC patients prior to chemotherapy, after one course of treatment and after two courses of treatment. RESULTS: The average levels of CK-2G2 in the serum of NSCLC patients was found to be significantly higher than that of the group of non-malignant patients as well as the healthy control group (p < 0.01). It was further observed that CK-2G2 is markedly higher in squamous-cell carcinoma than in adenocarcinoma (p < 0.05) whereas CK-2G2 was found to be higher in stages III and IV than stages I and II (p < 0.05) and CK-2G2 is markedly higher in large tumor size (> 3cm) than in small tumor size (< or = 3cm) (p < 0.05). Serum CK-2G2 levels for patients with cancer progression were found to increase after two courses of chemotherapy (p < 0.01) whereas patients with stabilized tumorigenesis or tumor regression showed a significant trend of CK-2G2 decrease (p < 0.01). CONCLUSIONS: Detection of the new tumor biomarker CK-2G2 has certain clinical values for early diagnosis, verification of diagnosis as well as classification of patients. Thus it is warranted that CK-2G2 be widely deployed as a new type of cost effective parameter for evaluating efficacy of chemotherapy of NSCLC.
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Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Queratina-19/sangue , Neoplasias Pulmonares/sangue , Fragmentos de Peptídeos/sangue , Adulto , Idoso , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Estudos de Casos e Controles , Feminino , Humanos , Medições Luminescentes/métodos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Estatísticas não ParamétricasRESUMO
The aim of this study is to explore the impact of professional training on teaching innovation among senior high school ideological and political teachers. By introducing the concept of basic psychological needs satisfaction as a mediating factor, the study seeks to uncover the mechanisms and patterns that manifest in teaching innovation within the Chinese cultural context. To gather empirical data, a questionnaire survey was administered to a sample of 780 teachers in this specialized field. The results showed that providing more professional training is an effective way to enhance teaching innovation. Drawing on Self-Determination Theory, the satisfaction of basic psychological needs (competence, relatedness, and autonomy) was found to play an important role in this process. Competence need satisfaction and relatedness need satisfaction played a mediating role, while autonomy need satisfaction played a moderating role. Based on these findings, several recommendations are provided to support the professional training of senior high school ideological and political teachers and enhance their innovation, including providing personalized training programs, building a mentor system, and allowing greater autonomy in school management.
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Deep rock structures are often subjected to complex cyclic disturbances generated by earthquakes and blasting vibrations. The rocks will resist disturbance with multiple stress levels, and the research on mechanical response is still insufficient under such conditions. A series of multi-level cyclic loading experiments were subjected to limestone specimens to obtain the stress-strain relation and fracture behavior. This study explored the effect of amplitude and cycle times on rocks. A Discrete Element Method model of rock specimens was established in Particle Flow Code 2D (PFC2D). The simulation results are coincidental with the experiment results. The results show that loading with low cycles can strengthen the rock, but loading with high cycles will present deteriorated effect on the rock. In the numerical simulation test, the initial crack will appear earlier with the amplitude increase. More micro cracks will be induced as the number of cycles per level increases. Moreover, tensile cracks are mainly distributed around the specimen when shear cracks widely appear in the central area. With the increase of amplitude, failure modes with mixed shear and tensile cracks will become universal.
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Soil-cement-bentonite (SCB) backfill has been widely used in constructing cut-off walls to inhibit groundwater movement in contaminated sites. This study prepares SCB backfill with fixed fluidity. We conducted a series of experiments to investigate the engineering characteristics and microscopic mechanism of the backfill. The results indicate that the water content in the slurry was more sensitive to the bentonite content. The unconfined compression strength (UCS) value increased with an increase in the cement content, and the change with an increase in bentonite content was not noticeable. The permeability coefficient decreased distinctly with an increase in the cement and bentonite contents. The porosity of the SCB backfill increased with increasing bentonite content and decreased with increasing cement content. The UCS of SCB backfill was linearly and negatively correlated with the porosity; the permeability coefficient was not significantly related to the porosity. The percentage of micro- and small-pore throats in the backfill increased with increasing bentonite and cement contents. As cement and bentonite content increased by 6% in the backfill, the proportion of micro- and small-pore throats increased by 0.7% and 1.2%, respectively. The percentage of micro- and small-pore throats is deduced to be more suitable as a characterization parameter for the permeability of the SCB backfill. The overall results of this study show that the reasonably proportioned SCB backfill has potential as an eco-friendly and cost-effective material. Based on the requirements of strength and permeability coefficient (UCS > 100 kPa, 28 days permeability coefficient <1 × 10-7 cm/s), we suggested using a backfill with 12% bentonite and 9% cement as the cut-off wall mix ratio.
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It is of great significance to study the distribution characteristics and transport of heavy metals in complex sedimentary environments and areas with intensive human activities. This study analyzed sediment size, heavy metal contents (Cu, Zn, Cd, Cr, and Pb), organic carbon content, and sulfide content in surface sediments collected from 27 sites in Chengbei Sea. The main controlling factors of the distribution and transport of heavy metals were discussed from the perspective of sediment dynamics. The concentrations of Cu, Zn, Cd, Cr, and Pb in surface sediments were 7.9-20.5 mg/kg, 33.8-94.6 mg/kg, 0.08-0.26 mg/kg, 6.3-62.3 mg/kg, and 3-13.4 mg/kg, respectively. According to the geoaccumulation index, the study area was not polluted by the heavy metals, except for Cd, which did not pollute only areas with relatively coarse-grained sediments. Combining the results of correlation analysis, tidal residual current analysis, sediment transport trend analysis, and principal component analysis confirmed that Cu, Zn, and Cd originate from natural sources, and their distribution characteristics are mainly controlled by the grain size of surface sediments. Cr and Pb could be attributed to human activities, such as oil exploration, and their distribution characteristics were affected by sediment transport and tidal residual current. Zonation of the sedimentary dynamic environment also provided reference for the relationship between the distribution of heavy metals in surface sediments and sedimentary environments.
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Metais Pesados , Poluentes Químicos da Água , Humanos , Sedimentos Geológicos/análise , Monitoramento Ambiental/métodos , Cádmio/análise , Chumbo/análise , Poluentes Químicos da Água/análise , Metais Pesados/análise , China , Medição de RiscoRESUMO
Background: The role of the histone ubiquitination-related gene in the cisplatin resistance of lung adenocarcinoma (LUAD) remains an intricate subject. Methods: We accessed transcriptome data of both wild type and cisplatin-resistant cells from the GSE108214 dataset, and garnered transcriptome and clinical data of LUAD patients from The Cancer Genome Atlas (TCGA) database. Utilizing the R software, we analyzed these public datasets in depth. Real-time Quantitative PCR (qPCR) was used to detect the RNA level of CUL4B. Effect of CUL4B on cell proliferation was evaluated using CCK8 and colony formation assay. Effect of CUL4B on cell invasion was evaluated using transwell assay. Cisplatin sensitivity was evaluated by calculating IC50. Results: Our analysis shed light on the significance of the histone ubiquitination-related gene, CUL4B, in relation to cisplatin resistance and the overall survival rates of LUAD patients. Notably, CUL4B was found to be overexpressed in both lung cancer tissues and cells. Meanwhile, in vitro experiments indicated can CUL4B significantly promote the proliferation, invasion and migration of lung cancer cells. Furthermore, suppressing CUL4B expression led to a noticeable reduction in the IC50 value of cisplatin in lung cancer cells. A deep dive into biological enrichment analysis revealed that among patients exhibiting high CUL4B expression, there was a pronounced activation of the G2M checkpoint and the PI3K/AKT/mTOR signaling pathways. Immune microenvironment analysis has revealed that patients with elevated CUL4B expression may exhibit increased infiltration of M2 macrophages, coupled with a reduced infiltration of CD8+ T cells and activated NK cells. Notably, we observed higher CUL4B expression among those who responded positively to immunotherapy. Conclusion: These findings underscore the significance of CUL4B in the resistance to cisplatin in lung cancer, highlighting its potential as a therapeutic target.
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The concentration profiles of various major and trace heavy metals (Cu, Pb, Zn, Cr, Cd, As, Hg, Ni, Li, and Co) were investigated along a 40.1-m-long sediment core in the offshore Jiangsu area of China, to assess their depositional trends and contamination levels. All metals, except Cd, exhibited similar profiles with high average concentrations during the Marine Isotope Stage 2-4 period. The sediment trace-metal concentrations were primarily related to grain size and sediment sources, with almost all heavy metals (except Cd) being positively correlated. Enrichment factors, geoaccumulation indices, and principal component analysis indicated no elemental enrichment or contamination. The high EF and Igeo values of As, Hg, and Li may be related to their background values.
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Mercúrio , Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Cádmio/análise , Monitoramento Ambiental , Medição de Risco , Metais Pesados/análise , Mercúrio/análise , China , Oligoelementos/análise , Sedimentos Geológicos , Poluentes Químicos da Água/análiseRESUMO
Gradient-structured ternary Fe-Co-Ni alloy coatings electrodeposited on steel substrates at various current densities from chloride baths were numerically and experimentally investigated. The electrodeposition process, considering hydrogen evolution and hydrolysis reaction, was modelled using the finite element method (FEM) and was based on the tertiary current distribution. The experimentally tested coating thickness and elemental contents were used to verify the simulation model. Although there was a deviation between the simulation and experiments, the numerical model was still able to predict the variation trend of the coating thickness and elemental contents. The influence of the current density on the coating characterization was experimentally studied. Due to hydrogen evolution, the coating surface exhibited microcracks. The crack density on the coating surface appeared smaller with increasing applied current density. The XRD patterns showed that the deposited coatings consisted of solid-solution phases α-Fe and γ (Fe, Ni) and the metallic compound Co3Fe7; the current density in the present studied range had a small influence on the phase composition. The grain sizes on the coating surface varied from 15 nm to 20 nm. The microhardness of the deposited coatings ranged from 625 HV to 655 HV. Meanwhile, the average microhardness increased slightly as the current density increased from 5 A/dm2 to 10 A/dm2 and then decreased as the current density further increased. Finally, the degree of anomaly along with the metal ion and hydrogen atom concentrations in the vicinity of the cathodic surface were calculated to investigate the anomalous codeposition behaviour.