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Objectives: N7-methylguanosine (m7G) plays a crucial role in mRNA metabolism and other biological processes. However, its regulators' function in Primary Sjögren's Syndrome (PSS) remains enigmatic. Methods: We screened five key m7G-related genes across multiple datasets, leveraging statistical and machine learning computations. Based on these genes, we developed a prediction model employing the extreme gradient boosting decision tree (XGBoost) method to assess PSS risk. Immune infiltration in PSS samples was analyzed using the ssGSEA method, revealing the immune landscape of PSS patients. Results: The XGBoost model exhibited high accuracy, AUC, sensitivity, and specificity in both training, test sets and extra-test set. The decision curve confirmed its clinical utility. Our findings suggest that m7G methylation might contribute to PSS pathogenesis through immune modulation. Conclusions: m7G regulators play an important role in the development of PSS. Our study of m7G-realted genes may inform future immunotherapy strategies for PSS.
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Objective: The purpose of this manuscript is to identify longitudinal trajectories of changes in triglyceride glucose (TyG) index and investigate the association of TyG index trajectories with risk of lean nonalcoholic fatty liver disease (NAFLD). Methods: Using data from 1,109 participants in the Health Management Cohort longitudinal study, we used Latent Class Growth Modeling (LCGM) to develop TyG index trajectories. Using a Cox proportional hazard model, the relationship between TyG index trajectories and incident lean NAFLD was analyzed. Restricted cubic splines (RCS) were used to visually display the dose-response association between TyG index and lean NAFLD. We also deployed machine learning (ML) via Light Gradient Boosting Machine (LightGBM) to predict lean NAFLD, validated by receiver operating characteristic curves (ROCs). The LightGBM model was used to create an online tool for medical use. In addition, NAFLD was assessed by abdominal ultrasound after excluding other liver fat causes. Results: The median age of the population was 46.6 years, and 440 (39.68%) of the participants were men. Three distinct TyG index trajectories were identified: "low stable" (TyG index ranged from 7.66 to 7.71, n=206, 18.5%), "moderate stable" (TyG index ranged from 8.11 to 8.15, n=542, 48.8%), and "high stable" (TyG index ranged from 8.61 to 8.67, n=363, 32.7%). Using a "low stable" trajectory as a reference, a "high stable" trajectory was associated with an increased risk of lean-NAFLD (HR: 2.668, 95% CI: 1.098-6.484). After adjusting for baseline age, WC, SBP, BMI, and ALT, HR increased slightly in "moderate stable" and "high stable" trajectories to 1.767 (95% CI:0.730-4.275) and 2.668 (95% CI:1.098-6.484), respectively. RCS analysis showed a significant nonlinear dose-response relationship between TyG index and lean NAFLD risk (χ2 = 11.5, P=0.003). The LightGBM model demonstrated high accuracy (Train AUC 0.870, Test AUC 0.766). An online tool based on our model was developed to assist clinicians in assessing lean NAFLD risk. Conclusion: The TyG index serves as a promising noninvasive marker for lean NAFLD, with significant implications for clinical practice and public health policy.
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Hepatopatia Gordurosa não Alcoólica , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Estudos Longitudinais , Glucose , Aprendizado de Máquina , TriglicerídeosRESUMO
Purpose: Both nonthyroidal illness syndrome (NTIS) and disseminated intravascular coagulation (DIC) are commonly occurred in sepsis. The objective of this study is to evaluate the association between NTIS and DIC, as well as their impacts on the mortality in adults with sepsis. Patients and methods: A total of 1219 septic patients in two Chinese academic centers from October 2012 and October 2022 were enrolled in analysis. We conduct logistic regression models to analyze the independent risk factors for DIC. Modified Poisson regression models are used to estimate the relative risk (RR) of NTIS on the 28 days mortality in septic patients with DIC. Correlation analysis between thyroid function parameters and coagulation parameters is performed with Pearson coefficient be reported. Results: DIC is diagnosed on 388 (31.8%) of all the 1219 enrolled septic patients within 72 hours after admission. In multivariate logistic regression models, NTIS (OR 3.19; CI 2.31-4.46; p<0.001) is a statistically significant independent risk factor for DIC after adjustment for potential confounders. Twenty-eight days mortality is significantly higher in DIC patients complicated with NTIS compared with the other DIC patients (23.2% vs 14.0%, p=0.024). This result is also robust in different modified Poisson regression models (Model 1: RR 1.46; CI 1.25-1.70; p<0.001; Model 2: RR 1.35; CI 1.14-1.60; p<0.001; Model 3: RR 1.18; CI 1.02-1.37; p=0.026). Correlation analysis reveals that the thyroid function parameters of FT3, FT4 and TSH only have weak correlations with coagulation parameters of platelet count, fibrinogen, FDP, D-dimers, PT, APTT and INR in sepsis. Conclusion: NTIS is an independent risk factor for DIC in adults with sepsis. DIC patients complicated with NTIS have significantly higher severity and higher rate of mortality.
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BACKGROUND: Resection of colorectal adenoma (CRA) prevents colorectal cancer; however, recurrence is common. We aimed to assess the association of the triglyceride-glucose (TyG) index with CRA occurrence and recurrence. METHODS: Data from 3392 participants at a hospital in China from 2020 to 2022 were analyzed. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). A restricted cubic spline was used to fit TyG index doseâresponse curves to recurrent adenomas. The discriminatory power of TyG index for predicting later recurrence was assessed with the area under the receiver operating characteristic (ROC) curve in 170 patients with a TyG index at initial adenoma diagnosis. RESULTS: One thousand five hundred ninety-six adenoma and 1465 normal participants were included in the occurrence analysis, and 179 recurrent and 152 nonrecurrent participants were included in the recurrence analysis. The TyG mutation was an independent risk factor for CRA occurrence and recurrence. After adjusting for confounders, the risk of adenoma in the participants in Q2, Q3, and Q4 groups of TyG was 1.324 (95% CI 1.020-1.718), 1.349 (95% CI 1.030-1.765), and 1.445 (95% CI 1.055-1.980) times higher than that of the Q1, respectively, and the risk of recurrence in the Q3 and Q4 groups was 2.267 (95% CI 1.096-4.691) and 2.824 (95% CI 1.199-6.648) times in Q1 group. Multiple logistic regression showed that the highest quartile of the TyG index was associated with a greater risk of advanced adenoma recurrence (OR 4.456, 95% CI 1.157-17.164), two or more adenomas (OR 5.079, 95% CI 1.136-22.714 [after removal of TyG index extreme values]), and proximal colon or both adenomas (OR 3.043, 95% CI 1.186-7.810). Subgroup analysis revealed that the association was found to be present only in participants of all age groups who were either male or without obesity, hyperglycemia, hypertension, or dyslipidemia (p < 0.05). ROC curves illustrated that the TyG index had good predictive efficacy for identifying recurrence, especially for patients with two or more adenomas (AUC 0.777, 95% CI 0.648-0.907). CONCLUSIONS: An increase in the TyG index is associated with an increased risk of adenoma occurrence and recurrence, with a stronger association with the latter.
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Adenoma , Carbamatos , Neoplasias Colorretais , Pirazinas , Piridinas , Humanos , Masculino , Glucose , Estudos Retrospectivos , Adenoma/epidemiologia , China/epidemiologia , Neoplasias Colorretais/epidemiologia , Triglicerídeos , Glicemia , Fatores de Risco , BiomarcadoresRESUMO
The importance of N6-methyladenine (m6A) in mRNA metabolism, physiology, pathology and other life processes is well recognized. However, the exact role of m6A regulators in primary Sjögren's syndrome (PSS) remains unclear. In this study, we used bioinformatics and machine learning random forest approach to screen eight key m6A regulators from the Gene Expression Omnibus GSE7451, GSE40611 and GSE84844 datasets. An accurate nomogram model for predicting PSS risk was established based on these regulators. And using consensus clustering, patients diagnosed with PSS were classified into two different m6A patterns. We found that patients in group B had higher m6A scores compared to those in group A: furthermore, both groups were closely related to immunity and possibly to other diseases. These results emphasise the important role of m6A regulators in the pathogenesis of PSS. Our study of m6A patterns may inform future immunotherapy strategies for PSS.
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INTRODUCTION: This study explores the association of individual cognition and social environment of smoking with autonomy over tobacco, providing evidence and insights to help smokers effectively prevent and reduce tobacco dependence. METHODS: Data were collected from 1389 participants, aged ≥15 years, by face-to-face interviews from June 2018 to November 2019 in central China. We assessed autonomy over tobacco using the Autonomy Over Smoking Scale (AUTOS), including Withdrawal Symptoms (WS), Psychological Dependence (PD) and Cue-induced Cravings (CC), and examined factors of individual cognition and social environment, as well as covariates, including demographic characteristics, health status, and smoking behavior. RESULTS: AUTOS total score was 16.92 ± 9.05, WS score was the lowest (4.40 ± 3.36) in the three subscales, and CC score was the highest (6.88 ± 3.2). After adjustment, WS score of having a greater awareness of smoking hazards to one's own health was lower than those who had no awareness (ß=0.14; 95% CI: -0.31-0.00), and the total score of AUTOS, the score of PD and CC for those who thought smoking was 'more helpful (high)' to interpersonal communication were higher than 'not helpful (not at all)' (ß=0.14; 95% CI: 0.01-0.28 with ß=0.16; 95% CI: 0.02-0.29; and ß=0.14; 95% CI: 0.00-0.28; respectively). Having a greater difficulty in smoking cessation was associated with higher AUTOS total and subscale scores (p<0.001). Notably, none of the social-environmental factors included had a significant association with AUTOS scores. CONCLUSIONS: Interventions targeting individual cognitive factors of tobacco dependence seem to be more effective in smoking cessation. Future research may explore the influence of family and workplace among social environmental factors, which may reveal the effect of a binding force.
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Introduction: Acute pancreatitis is a common gastrointestinal disease. The mortality of patients affected by severe acute pancreatitis (SAP) remains high. It is unclear whether high-dose intravenous vitamin C (HDIVC) therapy could improve the prognosis of these patients. The current prospective, randomized, double-blinded, placebo-controlled study will explore the effect of high-dose intravenous vitamin C therapy on the prognosis in patients with moderately severe and severe acute pancreatitis. Methods and design: A total of 418 participants with moderately severe and severe acute pancreatitis who meet the eligible criteria will be randomly assigned in a 1:1 ratio to receive treatment with HDIVC (200 mg/kg/24 h) or placebo (saline) for a period of 7 days. The primary outcome is 28-day mortality in these patients. The secondary outcomes include organ functions and interventions, laboratory tests, healthcare, and 90-day mortality. Ethics and dissemination: This protocol was approved by the institutional ethics board of the Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China (Registration Number: 2019-90). The report of the study will be published in peer-reviewed journals and presented at conferences, both nationally and internationally. Clinical trial registration: Chinese Clinical Trial Registry (ChiCTR1900022022). Version 1.5.
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Background: Nonthyroidal illness syndrome (NTIS) is a common endocrine dysfunction predicting unfavorable outcomes in critical illness. The objective of the study is to evaluate the association between different NTIS subtypes with outcomes in septic patients. Methods: Septic patients in two Chinese academic centers from October 2012 and October 2022 are enrolled in analysis. Multivariable regressions are used to assess associations between NTIS and outcomes. Outcomes include in-hospital mortality, length of stay in hospital (LOS), non-invasive ventilation failure and weaning failure. Patients with NTIS are categorized into 4 types according to the different levels of FT4 and TSH. The association between different NTIS subtypes and mortality are further analyzed. Survival curve is plotted using the Kaplan-Meier method. Results: After screening, a total of 1226 septic patients with complete thyroid hormones result are eventually enrolled. Among them, 520 (42.4%) patients are diagnosed as NTIS. In multivariable regression analysis, NTIS is independently associated with increased 30-days mortality (OR=1.759, CI 1.009-3.104, p=0.047), but has no association with 60-days mortality (OR=1.524, CI 0.893-2.618, p=0.123), 90-days mortality (OR=1.411, CI 0.831-2.408, p=0.203), LOS, non-invasive ventilation failure or weaning failure. In NTIS subtypes, NTIS patients with low FT3 and TSH levels, regardless of the FT4 values, have significantly higher mortality than euthyroid patients (30-days mortality, OR= 6.488, CI 1.546-27.808, p=0.01; 60-days mortality, OR=3.973, CI 1.006-15.579, p=0.046; 90-days mortality, OR=3.849, CI 0.977-15.088, p=0.051). This result is consistent in patients with low FT3 and FT4 levels, regardless of the TSH values (30-days mortality, OR=3.349, CI 1.402-7.957, p=0.006; 60-days mortality, OR= 2.594, CI 1.122-5.930, p=0.024; 90-days mortality, OR=2.55, CI 1.110-5.804, p=0.025). There is no survival difference between NTIS patients with low FT3 only and euthyroid patients. Survival plot shows the worst prognosis is in NTIS patients with low FT3, FT4 and TSH level. Conclusions: NTIS is frequent in sepsis. A reduction of FT3 together with FT4 or TSH, but not FT3 only, is associated with an increased risk of mortality.
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Sepse , Hormônios Tireóideos , Humanos , Estudos Retrospectivos , Prognóstico , Tireotropina , Sepse/complicaçõesRESUMO
Sintered agglomerate of synthetic mesoporous silica nanoparticles (MSNs) is an architected geomaterial that provides confinement-mediated flow and transport properties of fluids needed for environmental research such as geological subsurface energy storage or carbon capture. The design of those properties can be guided by numerical simulations but is hindered by the lack of method to characterize the permeable pores within MSNs due to pore size. This work uses the advances of an Individual Particle cryogenic transmission Electron Tomography (IPET) technique to obtain detailed 3D morphology of monodispersed MSNs with diameters below 50 nm. The 3D reconstructed density-maps show the diameters of those MSNs vary from 35-46 nm, containing connected intraparticle pores in diameter of 2-20 nm with a mean of 9.2 ± 3 nm, which is comparable to the mean interparticle pore diameters in sintered agglomerate. The characterization of the pore shape and dimensions provides key information for estimating the flow and transport properties of fluids within the sintered agglomerate of those MSNs and for modeling the atomic MSN structures needed for pore-fluid simulations.
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Measuring the value chain carbon footprints of listed companies is essential for cumulative climate actions and climate-efficient capital allocation. We trace the carbon emissions embodied in the value chains of Chinese listed companies and find that there is an increasing trend in terms of the carbon footprints of listed companies over the period 2010-2019. In 2019, the direct emissions from these companies reached 1.9 billion tonnes, accounting for 18.3% of national emissions. The indirect emissions were well over twice as large as the direct emissions from 2010 to 2019. Energy, construction and finance companies tend to have a greater volume of value chain carbon footprints, yet the distribution of their carbon footprints varies significantly. Finally, we apply the results to evaluate the financed emissions of leading asset managers' equity portfolio investment in China's stock market.
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Waterflooding is one of the geotechniques used to recover fuel sources from nanoporous geological formations. The scientific understanding of the process that involves the multiphase flow of nanoconfined fluids, however, has lagged, mainly due to the complex nanopore geometries and chemical compositions. To enable the benchmarked flow of nanoconfined fluids, architected geomaterials, such as synthesized mesoporous silica with tunable pore shapes and surface chemical properties, are used for designing and conducting experiments and simulations. This work uses a modified many-body dissipative particle dynamics (mDPD) model with accurately calibrated parameters to perform parametric flow simulations for studying the influences of waterflooding-driven power, pore shape, surface roughness, and surface wettability on the multiphase flow in heptane-saturated silica nanochannels. Remarkably, up to an 80% reduction in the effective permeability is found for water-driven heptane flow in a baseline 4.5-nm-wide slit channel when compared with the Hagen-Poiseuille equation. In the 4.5-nm-wide channels with architected surface roughness, the flow rate is found to be either higher or lower than the baseline case, depending on the shape and size of cross sections. High wettability of the solid surface by water is essential for achieving a high recovery of heptane, regardless of surface roughness. When the solid surface is less wetting or nonwetting to water, the existence of an optimal waterflooding-driven power is found to allow for the highest possible recovery. A detailed analysis of the evolution of the transient water-heptane interface in those nanochannels is presented to elucidate the underlying mechanisms that impact or dictate the multiphase flow behaviors.
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BACKGROUND: The calcium/calmodulin-dependent serine protein kinase gene (CASK) is an essential gene in mammals, critical for neurodevelopment. The purpose of this study is to expand the understanding of the diagnosis of CASK-linked disorders. MATERIALS/METHODS: From clinical and genetic mutational analyses, relevant data in 2 Han Chinese patients were collected and analyzed. Real-time quantitative PCR (RT-qPCR) was performed to investigate the CASK expression levels in the patients. The X-chromosome inactivation (XCI) patterns of the patients and their nuclear families were tested by quantitation of methylation of the polymorphic human androgen receptor (HUMARA) locus. RESULTS: Two Han Chinese patients both presented with intellectual disability (ID), microcephaly with pontine and cerebellar hypoplasia (MICPCH). Two de novo mutations of c.82C>T (p.Arg28*) and c.846C>G (p.Tyr282*) in CASK have been investigated and predicted to be deleterious, which have produced truncated proteins. The functional protein association network of STRING (http://string-db.org) generated three-dimensional (3D) atomic models based on protein sequences in CASK and two Arg28 and Tyr282 residues were marked. RT-qPCR showed lower copy numbers of CASK expression in the patients than in their parents, as well as the sex- and age- matched control groups. Patient 1 showed a skewed XCI pattern, while no related changes noted in patient 2. CONCLUSIONS: Patients carrying different nonsense variants may have different degrees of different clinical phenotypes. This study expands the spectrum of genotype and phenotype correlations of CASK-linked disorders in the Han Chinese ethnicity and provides new insights into the molecular mechanism.
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Deficiências do Desenvolvimento , Guanilato Quinases , Criança , Humanos , Deficiências do Desenvolvimento/genética , Guanilato Quinases/genética , Mutação , Proteínas Quinases/genéticaRESUMO
Superamphiphobic surfaces have attracted widespread attention because of their great potential for applications in biotechnology, optoelectronics, water/oil separation, etc. Re-entrant curvatures are widely reported to provide a metastable Cassie state for superamphiphobicity. For high contact angles, re-entrant surfaces with a small area fraction (f) are designed according to the Cassie equation. However, this will make the surfaces take high local pressures under a mechanical force and thus suffer from frangibility. Robustness and high repellency are seemingly mutually exclusive. Herein, contrary to Cassie's equation, we show that high contact angles (>150°) with a large f (69.4%) of water and oleic acid can be achieved by utilizing a large upward Laplace pressure with narrow and parallel channel geometries. We deeply studied the effect of Laplace pressure on superamphiphobicity and suppose that the larger upward Laplace pressure stops the droplet earlier and pins the contact line at a higher position, providing a higher contact angle. The similar effect of viscous force well supports our explanation. These findings enable us to obtain robust and durable superamphiphobic surfaces with an enlarged area fraction and simple re-entrant microstructures. Our work may open up design strategies for robust superamphiphobic surfaces with practical applications.
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Background: CircRNA plays an important role in cancer progression. However, the potential mechanism of circRNA in gastric cancer remains unknown. In this study, we aimed to investigate the specific mechanism of circALPL in gastric cancer. Methods: Using a high-throughput microarray, we found that circALPL was upregulated in gastric cancer cell lines. RT-qPCR was used to measure the circALPL expression level in gastric cell lines and tissue. Transwell, CCK-8, and metastasis assays were performed to learn the function after circALPL was inhibited. Results: circALPL downregulation suppresses the invasion and proliferation ability of gastric cancer cells. Additionally, the underlying pathway of circALPL was studied using luciferase reporter assays and RNA immunoprecipitation assays. The results showed that circALPL promotes gastric cancer progression by sponging miR-127, thus upregulating MTDH. Conclusion: The circALPL-miR-127-MTDH pathway plays a vital role in gastric cancer proliferation and metastasis. circALPL might be a new therapeutic target in gastric cancer.
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BACKGROUND: Chronic kidney disease (CKD) is one of the major causes of renal damage. Shenyan Fangshuai Recipe (SFR), a modified prescription of traditional medicine in China, showed potent effects in alleviating edema, proteinuria, and hematuria of CKD in clinical practices. In this study, we aimed to investigate scientific evidence-based efficacy as well as metabolic regulations of SFR in CKD treatment. MATERIALS AND METHODS: The effect of SFR on CKD was observed in a rat model which is established with oral administration of adenine-ethambutol mixture for 21 days. Further, metabolites in serum were detected and identified with ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). Metabolomics study was performed using Ingenuity Pathway Analysis (IPA) software. RESULTS: With H&E staining and Masson's trichrome, the results showed that chronic kidney damage is significantly rescued with SFR treatment and recovered to an approximately normal condition. Along with 44 differential metabolites discovered, the regulation of SFR on CKD was enriched in glycine biosynthesis I, mitochondrial L-carnitine shuttle pathway, phosphatidylethanolamine biosynthesis III, sphingosine-1-phosphate signaling, L-serine degradation, folate transformations I, noradrenaline and adrenaline degradation, salvage pathways of pyrimidine ribonucleotides, cysteine biosynthesis III (Mammalia), glycine betaine degradation, and cysteine biosynthesis/homocysteine degradation. Further, TGFß-1 and MMP-9 were observed playing roles in this regulatory process by performing immunohistochemical staining. CONCLUSION: SFR exerts potent effects of alleviating glomerular sclerosis and interstitial fibrosis in the kidney, mainly via integrated regulations on metabolism and production of homocysteine, L-carnitine, and epinephrine, as well as the expression of TGFß-1. This study provides evidence for SFR's protective effects on CKD and reveals the metabolic mechanism behind these benefits for the first time.
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The phase behavior of hydrocarbon fluids confined in porous media has been reported to deviate significantly from that in the bulk environment due to the existence of sub-10 nm pores. Though experiments and simulations have measured the bubble/dew points and sorption isotherms of hydrocarbons confined in both natural and synthetic nanopores, the confinement effects in terms of the strength of fluid-pore interactions tuned by surface wettability and chemistry have received comparably less discussion. More importantly, the underlying physics of confinement-induced phenomena remain obfuscated. In this work, we studied the phase behavior and capillary condensation of n-hexane to understand the effects of confinement at the molecular level. To systematically investigate the pore effects, we constructed two types of wall confinements; one is a structureless virtual wall described by the Steele potential and the other one is an all-atom amorphous silica structure with surface modified by hydroxyl groups. Our numerical results demonstrated the importance of fluid-pore interaction, pore size, and pore morphology effects in mediating the pressure-volume-temperature (PVT) properties of hydrocarbons. The most remarkable finding of this work was that the saturation pressure predicted from the van der Waals-type adsorption isothermal loop could be elevated or suppressed relative to the bulk phase, as illustrated in the graphical abstract. As the surface energy (i.e., fluid-pore interaction) decreased, the isothermal vapor pressure increased, indicating a greater preference for the fluid to exist in the vapor state. Sufficient reduction of the fluid-pore interactions could even elevate the vapor pressure above that of the bulk fluid.
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Whether or not the carbon tax is conducive to alleviating the pressure on employment reduction in coal resource-based areas is a subject worthy of in-depth study. We take the province of Shanxi, a typical coal resource-based area in China, as an example, and use the dynamic computable general equilibrium (CGE) model to simulate the impact of carbon tax on employment under various carbon tax revenue recycling schemes. We disaggregate the employment effect into demand effect, cost effect, factor-shift effect, and investment-pull effect to analyze the transmission path of the influence of carbon tax on employment. The results show that the carbon tax is conducive to alleviating the pressures on employment reduction in coal resource-based areas. Compared with the scenario of no carbon tax revenue recycling, the pressures on employment reduction under the scenario where carbon tax is returned to residents or enterprises in different forms, are allayed. More into detail, carbon tax has the least inhibiting effect on industry employment in case that tax revenue is returned to residents in the form of transfer payment. In addition, there is a prominent difference in the transmission path through which the carbon tax promotes employment, that is, the single effect, or the combination of demand effect, cost effect, factor-shift effect, and investment-pull effect. However, the carbon tax would obstruct employment principally through the demand effect.
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Reaction of 8-amino-5,6,7,8-tetrahydroquinoline with RuCl2(PPh3)3 at room temperature affords the ruthenium(ii) chelate (8-NH2-C9H10N)RuCl2(PPh3)2 (E), in which the two triphenylphosphine ligands are disposed mutually cis. By contrast, when the reaction is performed at reflux ligand oxidation/dehydrogenation occurs along with cis-trans reorganization of the triphenylphosphines to form the 8-imino-5,6,7-trihydroquinoline-ruthenium(ii) complex, (8-NH-C9H9N)RuCl2(PPh3)2 (F). Complex F can also be obtained in higher yield by heating a solution of E alone to reflux. Comparison of their molecular structures highlights the superior binding properties of the bidentate imine ligand in F over its amine-containing counterpart in E. Both complexes are highly effective in the transfer hydrogenation of a wide range of alkyl-, aryl- and cycloalkyl-containing ketones affording their corresponding secondary alcohols with loadings of as low as 0.1 mol%. Significantly, F can deliver excellent conversions even in bench quality 2-propanol in reaction vessels open to the air, whereas the catalytic efficiency of E is diminished by the presence of air but only operates efficiently under inert conditions.
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As modern medicine advances, various methodologies are being explored and developed in order to treat severe osteochondral defects in joints. However, it is still very challenging to cure the osteochondral defects due to their poor inherent regenerative capacity, complex stratified architecture, and disparate biomechanical properties. The objective of this study is to create novel three-dimensional (3D) printed osteochondral scaffolds with both excellent interfacial mechanical properties and biocompatibility for facilitating human bone marrow mesenchymal stem cell (MSC) growth and chondrogenic differentiation. For this purpose, we designed and 3D printed a series of innovative bi-phasic 3D models that mimic the osteochondral region of articulate joints. Our mechanical testing results showed that our bi-phasic scaffolds with key structures have enhanced mechanical characteristics in compression (a maximum Young's modulus of 31 MPa) and shear (a maximum fracture strength of 5768 N/mm(2)) when compared with homogenous designs. These results are also correlated with numerical simulation. In order to improve their biocompatibility, the scaffolds' surfaces were further modified with acetylated collagen (one of the main components in osteochondral extracellular matrix). MSC proliferation results demonstrated that incorporation of a collagen, along with biomimetically designed micro-features, can greatly enhance MSC growth after 5 days in vitro. Two weeks' chondrogenic differentiation results showed that our novel scaffolds (dubbed "key" scaffolds), both with and without surface collagen modification, displayed enhanced chondrogenesis (e.g., 130%, 114%, and 236% increases in glycosaminoglycan, type II collagen deposition, and total protein content on collagen-modified key scaffolds when compared with homogeneous controls).