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AIM: In patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI), a low serum albumin-to-creatinine ratio (sACR) is associated with elevated risk of poor short- and long-term outcomes. However, the relationship between sACR and pulmonary infection during hospitalization in patients with STEMI undergoing PCI remains unclear. METHODS: A total of 4,507 patients with STEMI undergoing PCI were enrolled and divided into three groups according to sACR tertile. The primary outcome was pulmonary infection during hospitalization, and the secondary outcome was in-hospital major adverse cardiovascular events (MACE) including stroke, in-hospital mortality, target vessel revascularization, recurrent myocardial infarction, and all-cause mortality during follow-up. RESULTS: Overall, 522 (11.6%) patients developed pulmonary infections, and 223 (4.9%) patients developed in-hospital MACE. Cubic spline models indicated a non-linear, L-shaped relationship between sACR and pulmonary infection (P=0.039). Receiver operating characteristic curve analysis indicated that sACR had good predictive value for both pulmonary infection (area under the ROC curve [AUC]=0.73, 95% CI=0.70-0.75, Pï¼0.001) and in-hospital MACE (AUC=0.72, 95% CI=0.69-0.76, Pï¼0.001). Kaplan-Meier survival analysis indicated that higher sACR tertiles were associated with a greater cumulative survival rate (Pï¼0.001). Cox regression analysis identified lower sACR as an independent predictor of long-term all-cause mortality (hazard ratio [HR]=0.96, 95% CI=0.95-0.98, Pï¼0.001). CONCLUSIONS: A low sACR was significantly associated with elevated risk of pulmonary infection and MACE during hospitalization, as well as all-cause mortality during follow-up among patients with STEMI undergoing PCI. These findings highlighted sACR as an important prognostic marker in this patient population.
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Background: Adiposity and adipokines are closely associated with obesity-related metabolic abnormalities, but little is known regarding whether abdominal obesity is linked to type 2 diabetes mellitus (T2DM) through circulating adiponectin levels. Thus, this large-population-based study was designed to investigate the mediating effect of adiponectin in the relationship between abdominal obesity and T2DM. Methods: A total of 232,438 adults who lived in Dongguan, Guangdong Province, China, were enrolled in the present study. The circulating adiponectin concentrations were measured using latex-enhanced immunoturbidimetric assay. The association between circulating adiponectin and other clinical parameters was detected by Spearman's correlation analysis. Restricted cubic spline (RCS) regression was also used to address the non-linearity of the relationship between waist circumference and diabetes. Mediation analyses of circulating adiponectin were conducted using linear and logistic regression. Results: Subjects with abdominal obesity had lower levels of circulating adiponectin (P < 0.001). The circulating adiponectin value was inversely related to BMI (r = -0.370, P < 0.001), waist circumference (r = -0.361, P < 0.001), and fasting plasma glucose (r = -0.221, P < 0.001). The RCS plot showed a non-linear relation linking waist circumference with T2DM (P for non-linearity < 0.001). Patients with abdominal obesity presented 2.062 times higher odds of T2DM in comparison with those with non-abdominal obesity (odds ratio, 2.062; 95% confidence interval, 1.969-2.161) after adjusting for confounders. In the mediation analyses, the circulating adiponectin mediated the association between abdominal obesity and T2DM, with a mediation effect of 41.02% after adjustments. The above results were consistent in both men and women. Conclusion: The relationship between abdominal obesity and T2DM is mediated through circulating adiponectin level in adults, suggesting that circulating adiponectin might be a potential predictor for controlling the adverse progression from adiposity to T2DM.
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Diabetes Mellitus Tipo 2 , Masculino , Adulto , Humanos , Feminino , Diabetes Mellitus Tipo 2/complicações , Obesidade Abdominal/complicações , Obesidade Abdominal/epidemiologia , Adiponectina , Análise de Mediação , Obesidade/complicaçõesRESUMO
AIMS: Observational evidence suggests a bidirectional relationship between cardiovascular diseases (CVDs) and pneumonia. However, the causality between CVDs and pneumonia remains undetermined. Thus, we aimed to investigate the bidirectional causality between CVDs and pneumonia using Mendelian randomization (MR) analysis. METHODS: Global genetic correlation analysis and bidirectional two-sample MR analysis were performed to infer the genetic correlation and causality between CVDs and pneumonia by using genome-wide association study (GWAS) summary data from GWAS meta-analysis study, FinnGen or UK Biobank consortium. Post-hoc power calculation was conducted to assess the power for detecting the causality. RESULTS: The linkage disequilibrium score regression analysis suggested a positive significant genetic correlation between CVDs and pneumonia. In the MR analysis, only genetically predicted ischemic stroke was causally associated with any pneumonia (odds ratio [OR]: 1.119, 95% confidence interval [CI]: 1.031-1.393), bacterial pneumonia (OR: 1.251, 95% CI: 1.032-1.516), and pneumococcal pneumonia (OR: 1.308, 95% CI: 1.093-1.565), but the causality was attenuated to non-significance after adjusting for deep venous thrombosis. However, the causal effects of pneumonia on CVDs were not detected. Post-hoc power calculations supported strong power (more than 80%) to detect the causality. CONCLUSIONS: Ischemic stroke is causally associated with an increased risk of pneumonia, but there is no evidence for the causal effect of pneumonia on CVDs. Our findings have important implications as they provide further support for the thrombosis risk screening as a strategy to reduce the incidence of pneumonia in patients with ischemic stroke.
This Mendelian randomization analysis aimed to investigate the bidirectional causality between cardiovascular diseases and pneumonia. Our findings support the causal association of ischemic stroke on pneumonia, but indicate no evidence for the causal effects of pneumonia on cardiovascular diseases. The causal association of ischemic stroke on pneumonia was revealed to rely on deep venous thrombosis, which provided further support for the thrombosis risk screening as a strategy to reduce the incidence of pneumonia in patients with ischemic stroke.
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Water desalination mediated by electrochemical reactions to directly capture and release salt at electrode materials offers a low-voltage method for producing freshwater. Developing new system designs has allowed electrode materials to maximize their capacity for salt separation, especially when a multichannel system is used to introduce a separate electrode rinse solution. Here, we show that the use of an additive can provide a new strategy for improving electrode capacity and, hence desalination performance, which so far has been limited to increasing the electrolyte concentration. A custom-built, 2/2-channel flow cell divided by two cation exchange membranes and an anion exchange membrane was fed with 50 mM NaCl as the feed (two inner channels) and 0.5 M NaCl containing up to 0.1 M phosphate as the electrode rinse (two outer channels). Using manganese oxide electrodes with phosphate buffer-mediated redox reactions exhibited an improved desalination capacity of 68.0 ± 5.2 mg g-1 (0.55 mA cm-2) and a rate of 5.6 ± 1.3 mg g-1 min-1 (0.96 mA cm-2). The improvement was attributed to the buffer that served as a proton donor for promoting the H+ insertion reaction of amorphous or poorly crystalline MnO2. Additionally, the buffering capacity against acidification and the creation of insoluble manganese phosphate on the electrode surface prevented the dissolution of Mn2+, which could otherwise occur at the anode due to a decrease in the local pH upon H+ deinsertion. Thus, the use of manganese oxide electrodes coupled with phosphate provides a new strategy of increasing electrode capacity for water desalination.
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Objective. Most quantitative magnetic resonance imaging (qMRI) methods are time-consuming. Multiple overlapping-echo detachment (MOLED) imaging can achieve quantitative parametric mapping of a single slice within around one hundred milliseconds. Nevertheless, imaging the whole brain, which involves multiple slices, still takes a few seconds. To further accelerate qMRI, we introduce multiband SENSE (MB-SENSE) technology to MOLED to realize simultaneous multi-slice T2mapping.Approach.The multiband MOLED (MB-MOLED) pulse sequence was carried out to acquire raw overlapping-echo signals, and deep learning was utilized to reconstruct T2maps. To address the issue of image quality degradation due to a high multiband factor MB, a plug-and-play (PnP) algorithm with prior denoisers (DRUNet) was applied. U-Net was used for T2map reconstruction. Numerical simulations, water phantom experiments and human brain experiments were conducted to validate our proposed approach.Main results.Numerical simulations show that PnP algorithm effectively improved the quality of reconstructed T2maps at low signal-to-noise ratios. Water phantom experiments indicate that MB-MOLED inherited the advantages of MOLED and its results were in good agreement with the results of reference method.In vivoexperiments for MB = 1, 2, 4 without the PnP algorithm, and 4 with PnP algorithm indicate that the use of PnP algorithm improved the quality of reconstructed T2maps at a high MB. For the first time, with MB = 4, T2mapping of the whole brain was achieved within 600 ms.Significance.MOLED and MB-SENSE can be combined effectively. This method enables sub-second T2mapping of the whole brain. The PnP algorithm can improve the quality of reconstructed T2maps. The novel approach shows significant promise in applications necessitating high temporal resolution, such as functional and dynamic qMRI.
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Introduction: It is unclear whether admission-blood-glucose-to-albumin ratio (AAR) predicts adverse clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) who are treated with percutaneous coronary intervention (PCI). Here, we performed a observational study to explore the predictive value of AAR on clinical outcomes. Methods: Patients diagnosed with STEMI who underwent PCI between January 2010 and February 2020 were enrolled in the study. The patients were classified into three groups according to AAR tertile. The primary outcome was in-hospital all-cause mortality, and the secondary outcomes were in-hospital major adverse cardiac events (MACEs), as well as all-cause mortality and MACEs during follow-up. Logistic regression, Kaplan-Meier analysis, and Cox proportional hazard regression were the primary analyses used to estimate outcomes. Results: Among the 3,224 enrolled patients, there were 130 cases of in-hospital all-cause mortality (3.9%) and 181 patients (5.4%) experienced MACEs. After adjustment for covariates, multivariate analysis demonstrated that an increase in AAR was associated with an increased risk of in-hospital all-cause mortality [adjusted odds ratio (OR): 2.72, 95% CI: 1.47-5.03, P = 0.001] and MACEs (adjusted OR: 1.91, 95% CI: 1.18-3.10, P = 0.009), as well as long-term all-cause mortality [adjusted hazard ratio (HR): 1.64, 95% CI: 1.19-2.28, P = 0.003] and MACEs (adjusted HR: 1.58, 95% CI: 1.16-2.14, P = 0.003). Receiver operating characteristic (ROC) curve analysis indicated that AAR was an accurate predictor of in-hospital all-cause mortality (AUC = 0.718, 95% CI: 0.675-0.761) and MACEs (AUC = 0.672, 95% CI: 0.631-0.712). Discussion: AAR is a novel and convenient independent predictor of all-cause mortality and MACEs, both in-hospital and long-term, for STEMI patients receiving PCI.
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BACKGROUND: Previous studies have shown that the stress hyperglycemia ratio (SHR), a parameter of relative stress-induced hyperglycemia, is an excellent predictive factor for all-cause mortality and major adverse cardiovascular events (MACEs) among patients with ST-segment elevation myocardial infarction (STEMI). However, its association with pulmonary infection in patients with STEMI during hospitalization remains unclear. METHODS: Patients with STEMI undergoing percutaneous coronary intervention (PCI) were consecutively enrolled from 2010 to 2020. The primary endpoint was the occurrence of pulmonary infection during hospitalization, and the secondary endpoint was in-hospital MACEs, composed of all-cause mortality, stroke, target vessel revascularization, or recurrent myocardial infarction. RESULTS: A total of 2,841 patients were finally included, with 323 (11.4%) developing pulmonary infection and 165 (5.8%) developing in-hospital MACEs. The patients were divided into three groups according to SHR tertiles. A higher SHR was associated with a higher rate of pulmonary infection during hospitalization (8.1%, 9.9%, and 18.0%, P < 0.001) and in-hospital MACEs (3.7%, 5.1%, and 8.6%, P < 0.001). Multivariate logistic regression analysis demonstrated that SHR was significantly associated with the risk of pulmonary infection during hospitalization (odds ratio [OR] = 1.46, 95% confidence interval [CI] 1.06-2.02, P = 0.021) and in-hospital MACEs (OR = 1.67, 95% CI 1.17-2.39, P = 0.005) after adjusting for potential confounding factors. The cubic spline models demonstrated no significant non-linear relationship between SHR and pulmonary infection (P = 0.210) and MACEs (P = 0.743). In receiver operating characteristic curve, the best cutoff value of SHR for pulmonary infection was 1.073. CONCLUSIONS: The SHR is independently associated with the risk of pulmonary infection during hospitalization and in-hospital MACEs for patients with STEMI undergoing PCI.
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Hiperglicemia , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Intervenção Coronária Percutânea/efeitos adversos , Resultado do Tratamento , Hiperglicemia/diagnóstico , Hiperglicemia/epidemiologia , Hospitalização , Fatores de RiscoRESUMO
BACKGROUND: The Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE) index has been recommended as an ideal indicator of body fat and exhibited significant correlation with cardiometabolic risk factors. However, whether the CUN-BAE index correlates with incident diabetes in Asian populations is unknown. Therefore, this longitudinal study was designed to evaluate the association between baseline CUN-BAE index and type 2 diabetes mellitus (T2DM). METHODS: This retrospective longitudinal study involved 15,464 participants of 18-79 years of age in the NAGALA (NAfld in the Gifu Area Longitudinal Analysis) study over the period of 2004-2015. Cox proportional hazards regression was performed to test the relationship between the baseline CUN-BAE index and diabetes incidence. Further stratification analysis was conducted to ensure that the results were robust. The diagnostic utility of the CUN-BAE index was tested by the receiver operating characteristic (ROC) curve. RESULTS: Over the course of an average follow-up of 5.4 years, 373 (2.41%) participants developed diabetes. A higher diabetes incidence was associated with higher CUN-BAE quartiles (P for trend< 0.001). Each 1 unit increase in CUN-BAE index was associated with a 1.08-fold and 1.14-fold increased risk of diabetes after adjustment for confounders in males and females, respectively (both P < 0.001). Stratification analysis demonstrated a consistent positive correlation between baseline CUN-BAE and diabetes incidence. Moreover, based on ROC analysis, CUN-BAE exhibited a better capacity for diabetes prediction than both body mass index (BMI) and waist circumference (WC) in both sexes. CONCLUSIONS: The baseline CUN-BAE level was independently related to the incidence of diabetes. Increased adiposity determined by CUN-BAE could be used as a strong nonlaboratory predictor of incident diabetes in clinical practice.
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Adiposidade , Diabetes Mellitus Tipo 2 , Masculino , Feminino , Humanos , Estudos Retrospectivos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Estudos Longitudinais , Obesidade/metabolismo , Índice de Massa Corporal , Circunferência da Cintura , Tecido Adiposo/metabolismo , Fatores de RiscoRESUMO
Two-dimensional covalent organic frameworks (COFs) are a new type of porous crystalline material constructed by the linkage of organic building units through covalent bonds to produce predetermined structures. Here, the electronic structure evolution induced by the charge redistribution during the construction of two-dimensional polymer networks (sp2c-COF-2 and COF-66) from building units to crystal frameworks is examined theoretically. The calculated results demonstrate that the electronic structure of the framework is controlled by the relative energy level between the frontier orbitals of organic building core and linker units as well as the charge transfer amount between them during the construction of the framework. Moreover, it is observed that a noncoplanar framework becomes more conjugated because the charge transfer amount between core and linker units becomes larger during the construction of 2D frameworks, which leads to a larger charge carrier mobility within the 2D structure of COFs. The charge carrier mobility along the z-direction of the COF crystal is dominated by the interface interaction between COF layers. Thereby, we believed reasonable design or selection of organic building units plays a key role in improving the electronic and optoelectronic properties of such 2D organic frameworks.
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Background: The serum uric acid/albumin ratio (sUAR), a novel inflammatory marker, effectively predicts acute kidney injury (AKI) and cardiovascular outcomes. However, whether the sUAR predicts post-contrast acute kidney injury (PC-AKI) in patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) remains uncertain. In this study, we evaluated the association between the sUAR and PC-AKI in patients with STEMI undergoing PCI. Methods: We consecutively recruited patients with STEMI who underwent PCI and stratified them into three groups according to the terciles of the sUAR. The primary outcome was the incidence of PC-AKI. The association between the sUAR and PC-AKI was assessed by multivariate logistic regression analysis. Results: A total of 2861 patients with STEMI were included in this study. The incidence of PC-AKI increased stepwise with increasing sUAR tercile (2.6% vs 4.0% vs 11.6%, p < 0.001), and the incidence of in-hospital major adverse clinical events (MACEs) was highest among patients in the Q3 group. Multivariate logistic regression analysis revealed that the sUAR was also an independent predictor of PC-AKI (continuous sUAR, per 1-unit increase, odds ratio [OR] [95% confidence interval (CI)]: 1.06 [1.02-1.10], p = 0.005; tercile of sUAR, OR [95% CI] for Q2 and Q3: 1.18 [0.69-2.01] and 1.85 [1.12-3.06], respectively, with Q1 as a reference) but not in-hospital MACEs. In the receiver operating characteristic (ROC) analysis, the area under the curve (AUC) of the sUAR for predicting PC-AKI was 0.708 (95% CI: 0.666-0.751), and ROC analysis also showed that the sUAR was superior to uric acid and albumin alone in predicting PC-AKI. Conclusion: Increasing sUAR was significantly associated with a higher risk of PC-AKI but not in-hospital MACEs in patients with STEMI who underwent PCI, suggesting that sUAR had a predictive value for PC-AKI after PCI in patients with STEMI. Further studies are required to confirm this finding.
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In this study, fuel ethanol production from food waste using enzymatic hydrolysis and fermentation was evaluated from techno-economic viewpoint. The plant was designed with a capacity of 10 t/d food waste and a lifetime of 15-year. The total capital cost, annual operation cost and annual net profits of the plant were US$ 367,552, US$ 155,959 and US$ 74,995.57, respectively. The plant was economically viable as long as the internal rate of return remained below 29.8%. The shortest payback time was 5 years with discount rate of 5%. The price of fuel ethanol and food waste treatment fee were the most important variables for the economic performance of the plant by sensitivity analysis. This work could provide the basic knowledge for techno-economic analysis of food waste treatment and promote the industrial production of fuel ethanol.
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Etanol , Eliminação de Resíduos , Fermentação , Alimentos , HidróliseRESUMO
Utilization of solar energy for photocatalytic H2 evolution coupled with value-added chemical synthesis is a promising avenue to address energy and environmental crises. Here, we report the hexamethylenetetramine (HMT) synthesis and H2 evolution from methanol and ammonia in one pot using a nanophotocatalyst of the conventional semiconductor TiO2 (P25) loaded with Pt (Pt/P25). The addition of ammonia inhibits byproduct ethylene glycol formation, promotes H2 evolution, and obtains HMT with high selectivity (>99.0%). The Pt valence state is regulated by calcination and reduction treatment, indicating that Pt/P25 is a stable catalyst for the photocatalytic synthesis of HMT from methanol and ammonia. The optimized formation rates of H2 and HMT are 71.53 and 11.39 mmol gcat -1 h-1, respectively. This work provides a green and sustainable pathway for the photocatalytic HMT synthesis coupled with H2 evolution under mild conditions.
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Electrochemical separation offers an energy-efficient means to desalinate brackish water, a relatively untapped but increasingly utilized water source for freshwater supply. Several electrochemical techniques are being developed to enable low-energy desalination combined with energy storage. We report a new approach that produced a peak power density of 6.0 mW cm-2 from the energy stored in iron cyanide (Fe-CN) and iron citrate (Fe-Cit) redox couples during water desalination, using asymmetric redox flow batteries (RFBs). Desalination and the charging of the redox couples occurred in a four-channel RFB cell. The stored energy was extracted in a two-channel RFB cell. Desalination of model brackish water (2.9 g L-1) to freshwater (0.5 g L-1) was also studied in a symmetric system using the environmentally benign Fe-Cit. The process was characterized by low energy consumption (0.56 kW h m-3), high productivity (41.1 L freshwater m-2 area h-1, representing practical operating conditions for brackish water desalination), and high water recovery (91% product-to-intake water ratio, addressing the environmental and economic challenges of brine disposal). The low cell voltage (<0.5 V) required in the reported system is ideally suited for developing modular desalination systems powered by renewables, including solar energy. Collectively, water-based RFBs for desalination and power production would lead to sustainable water-energy infrastructure.
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Purificação da Água , Água , Água Doce , Oxirredução , Luz Solar , Purificação da Água/métodosRESUMO
The structural tailoring of pores is essential to high-performance Fe/N/C electrocatalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells. Current strategies for pore structure engineering are usually accompanied with a drastic change of the intrinsic activity-related surface, which may mask the real effects of the porous structure on ORR activity. Herein, a mild carbon dioxide (CO2) etching method was used to flexibly tailor the pore structure of Fe/N/C electrocatalysts without drastic changes in their surface structure and property. In this way, via employing the Fe/N/C electrocatalysts as a model, the intrinsic impact of the pore structure on ORR activity was revealed. In addition, the CO2 etching method developed a high-quality electrocatalyst (sample Fe/N/C-5% CO2) with polarization performance exceeding that of the commercial Pt/C catalyst in the fuel cell working voltage region (>0.65 V). This work will promote the ongoing intensive studies on the rational design of the pore structures in the Fe/N/C electrocatalysts.
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Transition-metal carbides are important materials in heterogeneous catalysis. It remains challenging yet attractive in nanoscience to construct the active phase of carbide catalysts in a controllable manner and keep a sintering-resistant property in redox reactions, especially hydroprocessing. In this work, an integrated strategy was presented to synthesize stable and well-defined tungsten carbide nanoparticles (NPs) by assembling the metal precursor onto carbon nanotubes (CNTs), wrapping a thin polymeric layer, and following a controlled carburization. The polymer served as a soft carbon source to modulate the metal/carbon ratio in the carbides and introduced amorphous carbons around the carbides to prevent the NPs from sintering. The as-built p-WxC/CNT displayed high stability in the hydrogenolysis of aryl ether C-O bond in guaiacol for more than 150 h. Its activity was more than two and six times higher than those prepared via typical temperature-programmed reduction with gaseous carbon (WxC/CNT-TPR) and carbothermal reduction with intrinsic carbon support (WxC/CNT-CTR), respectively. Our p-WxC/CNT catalyst also achieved high efficiency for selective cleavage of the aryl ether C-O bonds in lignin-derived aromatic ethers, including anisole, dimethoxylphenol, and diphenyl ether, with a robust lifespan.
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Toluene methylation with methanol to produce xylene has been widely investigated. A simultaneous side reaction of methanol-to-olefin over zeolites is hard to avoid, resulting in an unsatisfactory methylation efficiency. Here, CO2 and H2 replace methanol in toluene methylation over a class of ZnZrO x -ZSM-5 (ZZO-Z5) dual-functional catalysts. Results demonstrate that the reactive methylation species (H3CO*; * represents a surface species) are generated more easily by CO2 hydrogenation than by methanol dehydrogenation. Catalytic performance tests on a fixed-bed reactor show that 92.4% xylene selectivity in CO-free products and 70.8% para-xylene selectivity in xylene are obtained on each optimized catalyst. Isotope effects of H2/D2 and CO2/13CO2 indicate that xylene product is substantially generated from toluene methylation rather than disproportionation. A mechanism involving generation of reactive methylation species on ZZO by CO2 hydrogenation and migration of the methylation species to Z5 pore for the toluene methylation to form xylene is proposed.
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The selective hydrogenation of phenolics to cyclohexanones is an important process in both industrial application and utilization of fossil and renewable feedstocks. However this process remains a challenge in achieving high conversion of phenolics and high selectivity of ketones under mild reaction conditions. In this work, TiO2 nanowires (TNWs) are successfully synthesized by using an integrated method and the ultra-small Pd clusters were then deposited onto the TNWs by photoreduction. The obtained Pd/TNW catalyst shows superior catalytic performances in the hydrogenation of phenolic derivatives to the corresponding cyclohexanones. In particular, a nearly full conversion of phenol with high selectivity (>99.0%) to cyclohexanone can be achieved at 50 °C and 5.0 bar H2 in water. A series of characterization studies by means of XRD, XPS, EPR, FTIR, TPD, STEM, and kinetic studies indicate that abundant exposed Lewis acid and basic sites on the surface of TNWs play important roles in the activation of phenolics and desorption of cyclohexanones, while the Pd clusters by photodeposition can attain a hybrid of Pd0 and Pd2+ species to facilitate the activation of dihydrogenation. A plausible catalytic pathway with synergistic effects of TNWs and Pd species is then proposed.
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The efficient hydrodeoxygenation (HDO) of lignin-derived oxygenates is essential but challenging owing to the inherent complexity of feedstock and the lack of effective catalytic approaches. A catalytic strategy has been developed that separates C-O hydrogenolysis and aromatic hydrogenation on different active catalysts with interoperation that can achieve high oxygen removal in lignin-derived oxygenates. The flexible use of tungsten carbide for C-O bond cleavage and a nickel catalyst with controlled particle size for arene hydrogenation enables the tunable production of cyclohexane and cyclohexanol with almost full conversion of guaiacol. Such integration of dual catalysts in close proximity enables superior HDO of bio-oils into liquid alkanes with high mass and carbon yields of 27.9 and 45.0â wt %, respectively. This finding provides a new effective strategy for practical applications.
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AIM: Irisin is first discovered as a potential mediator of obesity related energy homeostasis. Recent studies indicate that irisin is associated with endothelial dysfunction and atherosclerosis in patients with type 2 diabetes. Our objective was to examine the relationship between irisin and urinary albumin excretion in patients with type 2 diabetes. METHODS: 100 newly diagnosed patients with type 2 diabetes and 100 healthy subjects were selected. Serum irisin levels were measured by ELISA, and urine albumin was measured by radioimmunoassay. High resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperemia (flow-mediated arterial dilation, FMD) and after sublingual glyceryltrinitrate. RESULTS: Patients with type 2 diabetes presented decreased irisin levels when compared to controls (14.12±3.93 versus 28.98±2.56ng/ml, P=0.015).Serum irisin levels in the microalbuminuric and macroalbuminuria subgroup were 9.89±1.56ng/ml and 5.67±1.89ng/ml, respectively, which were significantly lower than those in the normoalbuminuria (15.97±3.12ng/ml). In comparison to microalbuminuric subgroup, macroalbuminuria subgroup had lower levels of irisin. By dividing the distribution of serum irisin levels into quartiles, FMD was increased gradually with the increase of serum irisin levels (P<0.001). Multiple stepwise linear regression analysis showed that FMD (ß=0.75, P=0.002), 2-hBG (ß=-0.25, P=0.038) and UAE (ß=-0.87, P=0.008) were significantly associated with irisin. Pearson's correlation analyses showed a negative correlation between irisin and logUAE (r=-0.57) and between FMD and logUAE (r=-0.47), and positive correlations between irisin and FMD (r=0.51). CONCLUSIONS: Decreased plasma levels of irisin seem to be associated with UAE and FMD in patients with type 2 diabetes.