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Precise electrochemical synthesis of commodity chemicals and fuels from CO2 building blocks provides a promising route to close the anthropogenic carbon cycle, in which renewable but intermittent electricity could be stored within the greenhouse gas molecules. Here, we report state-of-the-art CO2-to-HCOOH valorization performance over a multiscale optimized Cu-Bi cathodic architecture, delivering a formate Faradaic efficiency exceeding 95% within an aqueous electrolyzer, a C-basis HCOOH purity above 99.8% within a solid-state electrolyzer operated at 100 mA cm-2 for 200 h and an energy efficiency of 39.2%, as well as a tunable aqueous HCOOH concentration ranging from 2.7 to 92.1 wt%. Via a combined two-dimensional reaction phase diagram and finite element analysis, we highlight the role of local geometries of Cu and Bi in branching the adsorption strength for key intermediates like *COOH and *OCHO for CO2 reduction, while the crystal orbital Hamiltonian population analysis rationalizes the vital contribution from moderate binding strength of η2(O,O)-OCHO on Cu-doped Bi surface in promoting HCOOH electrosynthesis. The findings of this study not only shed light on the tuning knobs for precise CO2 valorization, but also provide a different research paradigm for advancing the activity and selectivity optimization in a broad range of electrosynthetic systems.
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The interfacial adsorption structure of an organic leveler decides its functionality in Cu interconnect electroplating and is yet far from clear. In this work, in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) and electrochemical quartz crystal microbalance (EQCM) in conjunction with density functional theory (DFT) calculations are applied to unravel the interfacial adsorption of the classic dye leveler Janus Green B (JGB) at a Cu electrode and understand its polarization property against Cu electrodeposition from an adsorption structure perspective. ATR-SEIRAS measurements and DFT calculations reveal that the N=N bond of the JGB molecule splits via reductive hydrogenation, forming two fragments of contrasting adsorption configurations. JGB exhibits the strongest inhibition effect on Cu deposition among all the tested additives including individual and mixed fragments, due to the highest coverage of organic adsorbates from JGB dissociation, as measured by EQCM. This work highlights the advantage of surface sensitive analytical tools in understanding the structure-performance of levelers.
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The Si window is the most widely used internal reflection element (IRE) for electrochemical attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), yet local chemical etching on Si by concentrated OH- anions bottlenecks the reliable application of this method in strong alkaline electrolytes. In this report, atomic layer deposition of a 25 nm nonconductive TiO2 barrier layer on the reflecting plane of a Si prism is demonstrated to address this challenge. In situ ATR-SEIRAS measurement on a Au film electrode with the Si/TiO2 composite IRE in 1 M NaOH reveals reversible global spectral features without spectral distortion at 1000-1300 cm-1, in stark contrast to those obtained with a bare Si window. By applying this structured ATR-SEIRAS, ethanol electrooxidation on a Pt/C catalyst in 1 and 5 M NaOH is explored, manifesting that such high pH values prevent the adsorption of as-formed acetate in the C2 pathway but not that of CO intermediate in the C1 pathway.
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Atrial fibrillation (AF) is the most common arrhythmia, and atrial fibrosis is a pathological hallmark of structural remodeling in AF. Prostaglandin I2 (PGI2) can prevent the process of fibrosis in various tissues via cell surface Prostaglandin I2 receptor (IP). However, the role of PGI2 in AF and atrial fibrosis remains unclear. The present study aimed to clarify the role of PGI2 in angiotensin II (Ang II)-induced AF and the underlying molecular mechanism. PGI2 content was decreased in both plasma and atrial tissue from patients with AF and mice treated with Ang II. Treatment with the PGI2 analog, iloprost, reduced Ang II-induced AF and atrial fibrosis. Iloprost prevented Ang II-induced atrial fibroblast collagen synthesis and differentiation. RNA-sequencing analysis revealed that iloprost significantly attenuated transcriptome changes in Ang II-treated atrial fibroblasts, especially mitogen-activated protein kinase (MAPK)-regulated genes. We demonstrated that iloprost elevated cAMP levels and then activated protein kinase A, resulting in a suppression of extracellular signal-regulated kinase1/2 and P38 activation, and ultimately inhibiting MAPK-dependent interleukin-6 transcription. In contrast, cardiac fibroblast-specific IP-knockdown mice had increased Ang II-induced AF inducibility and aggravated atrial fibrosis. Together, our study suggests that PGI2/IP system protects against atrial fibrosis and that PGI2 is a therapeutic target for treating AF.The prospectively registered trial was approved by the Chinese Clinical Trial Registry. The trial registration number is ChiCTR2200056733. Data of registration was 2022/02/12.
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Angiotensina II , Fibrilação Atrial , Remodelamento Atrial , Epoprostenol , Camundongos Endogâmicos C57BL , Transdução de Sinais , Animais , Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Fibrilação Atrial/induzido quimicamente , Fibrilação Atrial/prevenção & controle , Camundongos , Humanos , Masculino , Transdução de Sinais/efeitos dos fármacos , Remodelamento Atrial/efeitos dos fármacos , Epoprostenol/metabolismo , Fibrose , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Átrios do Coração/efeitos dos fármacos , Iloprosta/farmacologia , Receptores de Epoprostenol/metabolismo , Receptores de Epoprostenol/genética , FemininoRESUMO
A series of freeze-thaw cycling tests, as well as cyclic loading and unloading tests, have been conducted on nodular sandstones to investigate the effect of fatigue loading and freeze-thaw cycling on the damage evolution of fractured sandstones based on damage mechanics theory, the microstructure and sandstone pore fractal theory. The results show that the number of freeze-thaw cycles, the cyclic loading level, the pore distribution and the complex program are important factors affecting the damage evolution of rocks. As the number of freeze-thaw cycles rises, the peak strength, modulus of elasticity, modulus of deformation and damping ratio of the sandstone all declined. Additionally, the modulus of elasticity and deformation increase nonlinearly as the cyclic load level rises. With the rate of increase decreasing, while the dissipation energy due to hysteresis increases gradually and at an increasing rate, and the damping ratio as a whole shows a gradual decrease, with a tendency to increase at a later stage. The NRM (Nuclear Magnetic Resonance) demonstrated that the total porosity and micro-pores of the sandstone increased linearly with the number of freeze-thaw cycles and that the micro-porosity was more sensitive to freeze-thaw, gradually shifting towards meso-pores and macro-pores; simultaneously, the SEM (Scanning Electron Microscope) indicated that the more freeze-thaw cycles there are, the more micro-fractures and holes grow and penetrate each other and the more loose the structure is, with an overall nest-like appearance. To explore the mechanical behavior and mechanism of cracked rock in high-altitude and alpine areas, a damage model under the coupling of freeze-thaw-fatigue loading was established based on the loading and unloading response ratio theory and strain equivalence principle.
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PtRu alloys have been recognized as the state-of-the-art catalysts for the methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs). However, their applications in DMFCs are still less efficient in terms of both catalytic activity and durability. Rare earth (RE) metals have been recognized as attractive elements to tune the catalytic activity, while it is still a world-class challenge to synthesize well-dispersed Pt-RE alloys. Herein, we developed a novel hydrogen-assisted magnesiothermic reduction strategy to prepare a highly dispersed carbon-supported lutetium-doped PtRu catalyst with ultrafine nanoclusters and atomically dispersed Ru sites. The PtRuLu catalyst shows an outstanding high electrochemical surface area (ECSA) of 239.0 m2 gPt-1 and delivers an optimized MOR mass activity and specific activity of 632.5 mA mgPt-1 and 26 A cmPt-2 at 0.4 V vs saturated calomel electrode (SCE), which are 3.6 and 3.5 times of commercial PtRu-JM and an order higher than PtLu, respectively. These novel catalysts have been demonstrated in a high-temperature direct methanol fuel cell running in a temperature range of 180-240 °C, achieving a maximum power density of 314.3 mW cm-2. The AC-STEM imaging, in situ ATR-IR spectroscopy, and DFT calculations disclose that the high performance is resulted from the highly dispersed PtRuLu nanoclusters and the synergistic effect of the atomically dispersed Ru sites with PtRuLu nanoclusters, which significantly reduces the CO* intermediates coverage due to the promoted water activation to form the OH* to facilitate the CO* removal.
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As the only essential amino acid containing elemental sulphur, L-methionine has important physiological and biochemical functions in living organisms. However, the fermentative production of L-methionine has not met the requirements of industrial production because of its low production level. In this paper, the fermentation process of an efficient L-methionine producing strain E. coli W3110ΔIJAHFEBC trc-fliY trc-malY/PAM glyA-22 metF constructed previously was systematically optimized. Based on the optimal initial glucose concentration, the effects of different fed-batch fermentation processes, including DO-Stat, pH-Stat, controlling residual sugar control at different level and feeding glucose with constant rate, on L-methionine fermentation were studied. It was found that the control of glucose concentration greatly affected the fermentation process. Subsequently, an optimal fed-batch fermentation process was developed, where the L-methionine titer was increased to 31.71 g/L, the highest yield reported to date, while the fermentation time was shortened to 68 h. Meanwhile, a fermentation kinetics model under the optimal fed-batch fermentation conditions was established, which fitted well with the biosynthesis process of L-methionine. This study may facilitate further development of the fermentative production of L-methionine.
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Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Metionina/metabolismo , Proteínas de Escherichia coli/metabolismo , Glucose/metabolismo , Proteínas de TransporteRESUMO
Plasmon-mediated electrocatalysis that rests on the ability of coupling localized surface plasmon resonance (LSPR) and electrochemical activation, emerges as an intriguing and booming area. However, its development seriously suffers from the entanglement between the photoelectronic and photothermal effects induced by the decay of plasmons, especially under the influence of applied potential. Herein, using LSPR-mediated CO2 reduction on Ag electrocatalyst as a model system, we quantitatively uncover the dominant photoelectronic effect on CO2 reduction reaction over a wide potential window, in contrast to the leading photothermal effect on H2 evolution reaction at relatively negative potentials. The excitation of LSPR selectively enhances the CO faradaic efficiency (17-fold at -0.6â VRHE ) and partial current density (100-fold at -0.6â VRHE ), suppressing the undesired H2 faradaic efficiency. Furthermore, in situ attenuated total reflection-surface enhanced infrared absorption spectroscopy (ATR-SEIRAS) reveals a plasmon-promoted formation of the bridge-bonded CO on Ag surface via a carbonyl-containing C1 intermediate. The present work demonstrates a deep mechanistic understanding of selective regulation of interfacial reactions by coupling plasmons and electrochemistry.
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This study systematically explores the impact of the anodic flow field design on the transport of O2 bubble and subsequent energy efficiency in electrolysis devices. Two distinct configurations, namely a conventional serpentine flow panel and an interdigitated flow panel, are integrated at the anode side of the electrolyzer. The interdigitated flow field exhibits superior performance in both alkaline water splitting and CO2 reduction despite the experience of an increased pressure drop. Numerical simulations reveal that the enhanced convective flow of the O2 bubbles induced by a forced anolyte flow through the porous electrode within the interdigitated panel design resulted in a 3 orders of magnitude increase in the level of the O2 bubble transport compared to the serpentine configuration. These findings not only underscore the significance of flow field design on bubble management but also provide a basis for advancing the electrolysis efficiency at industrial-level current densities.
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Introduction: Myocardial infarction (MI) is a fatal manifestation of coronary heart disease, and its underlying mechanism is still largely unknown. Lipid levels and composition alterations predict the risk of MI complications. Glycerophospholipids (GPLs) are important bioactive lipids and play a crucial role in the development of cardiovascular diseases. However, the metabolic changes in the GPLs profile during post-MI injury remain unknown. Methods: In the current study, we constructed a classic MI model by ligating the left anterior descending branch and assessed the alterations in both plasma and myocardial GPLs profiles during the reparative phase post-MI by liquid chromatography-tandem mass spectrometry analysis. Results: We found that myocardial GPLs, but not plasma GPLs, were markedly changed after MI injury. Importantly, MI injury is associated with decreased phosphatidylserine (PS) levels. Consistently, the expression of phosphatidylserine synthase 1 (PSS1), which catalyzes the formation of PS from its substrate phosphatidylcholine, was significantly reduced in heart tissues after MI injury. Furthermore, oxygen-glucose deprivation (OGD) inhibited PSS1 expression and reduced PS levels in primary neonatal rat cardiomyocytes, while overexpression of PSS1 restored the inhibition of PSS1 and the reduction in PS levels caused by OGD. Moreover, overexpression of PSS1 abrogated, whereas knockdown of PSS1 aggravated, OGD-induced cardiomyocyte apoptosis. Conclusions: Our findings revealed that GPLs metabolism was involved in the reparative phase post-MI, and cardiac decreased PS levels, resulting from inhibition of PSS1, are important contributor to the reparative phase post-MI. PSS1 overexpression represents a promising therapeutic strategy to attenuate MI injury.
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A wide spectrum of state-of-the-art characterization techniques have been devised to monitor the electrode-electrolyte interface that dictates the performance of electrochemical devices. However, coupling multiple characterization techniques to realize in situ multidimensional analysis of electrochemical interfaces remains a challenge. Herein, we presented a hyphenated differential electrochemical mass spectrometry and attenuated total reflection surface enhanced infrared absorption spectroscopy analytical method via a specially designed electrochemical cell that enables a simultaneous detection of deposited and volatile interface species under electrochemical reaction conditions, especially suitable for non-aqueous, electrolyte-based energy devices. As a proof of concept, we demonstrated the capability of the homemade setup and obtained the valuable reaction mechanisms, by taking the tantalizing reactions in non-aqueous lithium-ion batteries (i.e., oxidation and reduction processes of carbonate-based electrolytes on Li1+xNi0.8Mn0.1Co0.1O2 and graphite surfaces) and lithium-oxygen batteries (i.e., reversibility of the oxygen reaction) as model reactions. Overall, we believe that the coupled and complementary techniques reported here will provide important insights into the interfacial electrochemistry of energy storage materials (i.e., in situ, multi-dimensional information in one single experiment) and generate much interest in the electrochemistry community and beyond.
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BACKGROUND: Myocardial ischemia-reperfusion (I/R) injury causes cardiac dysfunction to myocardial cell loss and fibrosis. Prevention of cell death is important to protect cardiac function after I/R injury. The process of reperfusion can lead to multiple types of cardiomyocyte death, including necrosis, apoptosis, autophagy, and ferroptosis. However, the time point at which the various modes of cell death occur after reperfusion injury and the mechanisms underlying ferroptosis regulation in cardiomyocytes are still unclear. METHODS: Using a left anterior descending coronary artery ligation mouse model, we sought to investigate the time point at which the various modes of cell death occur after reperfusion injury. To discover the key molecules involved in cardiomyocyte ferroptosis, we performed a metabolomics study. Loss/gain-of-function approaches were used to understand the role of 15-lipoxygenase (Alox15) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (Pgc1α) in myocardial I/R injury. RESULTS: We found that apoptosis and necrosis occurred in the early phase of I/R injury, and that ferroptosis was the predominant form of cell death during the prolonged reperfusion. Metabolomic profiling of eicosanoids revealed that Alox15 metabolites accumulated in ferroptotic cardiomyocytes. We demonstrated that Alox15 expression was specifically increased in the injured area of the left ventricle below the suture and colocalized with cardiomyocytes. Furthermore, myocardial-specific knockout of Alox15 in mice alleviated I/R injury and restored cardiac function. 15-Hydroperoxyeicosatetraenoic acid (15-HpETE), an intermediate metabolite derived from arachidonic acid by Alox15, was identified as a trigger for cardiomyocyte ferroptosis. We explored the mechanism underlying its effects and found that 15-HpETE promoted the binding of Pgc1α to the ubiquitin ligase ring finger protein 34, leading to its ubiquitin-dependent degradation. Consequently, attenuated mitochondrial biogenesis and abnormal mitochondrial morphology were observed. ML351, a specific inhibitor of Alox15, increased the protein level of Pgc1α, inhibited cardiomyocyte ferroptosis, protected the injured myocardium, and caused cardiac function recovery. CONCLUSIONS: Together, our results established that Alox15/15-HpETE-mediated cardiomyocyte ferroptosis plays an important role in prolonged I/R injury.
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Araquidonato 15-Lipoxigenase , Ferroptose , Traumatismo por Reperfusão Miocárdica , Animais , Camundongos , Apoptose , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 12-Lipoxigenase/farmacologia , Araquidonato 15-Lipoxigenase/genética , Araquidonato 15-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/farmacologia , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Necrose/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ubiquitinas/metabolismo , Ubiquitinas/farmacologiaRESUMO
Introduction: Nanobubble is an innovative ultrasound contrast agent that triggers the development of targeted imaging of HER2-positive breast cancer by combining with HER2 affibody and IR783. HPPH is a second-generation photosensitiser that is effective in treating tumours. Hence, the nanobubble-IR783-HPPH-affibody (NIHA) complex demonstrates considerable potential in the treatment of HER2-positive breast cancer. Methods: We fabricated the NIHA complex via an advanced thin-film hydration method and detected its characteristics such as particle size, morphology, stability, and cytotoxicity. Moreover, the effect of NIHA complex with laser on HER2-positive breast cancer was confirmed via in vitro and in vivo experiments. Results: The NIHA complex was spheroid, stable and exhibited no cytotoxicity; moreover, its particle size was 524.8 ± 53.3 nm (n = 5). In combination with laser treatment, NIHA complex reduced the cell viability and tumour volume, induced apoptosis of HER2-positive breast cancer cells, and prolonged survival of nude mice. Conclusion: The newly prepared NIHA complex with laser treatment has the potential on treating HER2-positive breast cancer.
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Lasers , Neoplasias , Animais , Camundongos , Camundongos Nus , Linhagem Celular Tumoral , Ultrassonografia , Receptor ErbB-2RESUMO
Ethanol, as a sustainable biomass fuel, is endowed with the merits of theoretically high energy density and environmental friendliness yet suffers from sluggish kinetics and low selectivity toward the desired complete electrooxidation (C1 pathway). Here, the localized surface plasmon resonance (LSPR) effect is explored as a manipulating knob to boost electrocatalytic ethanol oxidation reaction in alkaline media under ambient conditions by appropriate visible light. Under illumination, Au@Pt nanoparticles with plasmonic core and active shell exhibit concurrently higher activity (from 2.30 to 4.05 A mgPt-1 at 0.8 V vs RHE) and C1 selectivity (from 9 to 38% at 0.8 V). In situ attenuated total reflection-surface enhanced infrared absorption spectroscopy (ATR-SEIRAS) provides a molecular level insight into the LSPR promoted C-C bond cleavage and the subsequent CO oxidation. This work not only extends the methodology hyphenating plasmonic electrocatalysis and in situ surface IR spectroscopy but also presents a promising approach for tuning complex reaction pathways.
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Diabetic retinopathy (DR) is increasingly becoming a main complication of diabetes, and is difficult to cure. In our research, network pharmacology analysis suggested that both compound Danshen dripping pills (CDDP) and bezafibrate (BZF) have potential protective effects against DR and the two drugs may act synergistically. The pharmacological effects of the coadministration of CDDP and BZF were elucidated in db/db mice, which simulate DR. Fluorescein fundus angiography showed that coadministration attenuated vascular leakage. Optical coherence tomography and hematoxylin and eosin staining showed that coadministration improved retinal thickness better than CDDP monotherapy. In addition, cell fluorescence images of reactive oxygen species revealed that coadministration of CDDP and BZF had more potent effects against oxidative stress than CDDP monotherapy. Metabolomics analysis showed that coadministration reduced the ratio of oxidized glutathione to reduced glutathione further than CDDP monotherapy. Coadministration of CDDP and BZF may provide additional protective effects by resisting vascular leakage, increasing retinal thickness, and inhibiting inflammation and oxidative stress in DR.
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In situ spectroscopic characterization of the interfacial structure of an organic additive at a Cu electrode is essential for a mechanistic understanding of Cu superfilling at the molecular level. In this work, we demonstrate wide-frequency attenuated total reflection surface-enhanced infrared absorption spectroscopy (wf-ATR-SEIRAS) to elucidate the dissociative adsorption of bis(sodium sulfopropyl)-disulfide (a typical accelerator) on a Cu electrode in conjunction with the electrochemical quartz crystal microbalance measurement and modeling calculations. The wf-ATR-SEIRAS clearly identifies the peaks featuring the sulfonate and methylene groups as well as the C-Ssulfonate and C-Sthiol vibrations of the adsorbate. Analysis of relative peak intensities from 1100 to 650 cm-1 reveals a more tilted alkyl chain axis for the thiolate on Cu than that on Au, which is supported by comparative density functional theory calculations. This work opens a new avenue for the wf-ATR-SEIRAS to study interfacial structures of electroplating additives related to advanced microelectronics manufacture.
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Compelling data have indicated menopause-associated increase in cardiovascular disease in women, while the underlying mechanisms remain largely unknown. It is established that changes of intestinal microbiota affect cardiovascular function in the context of metabolic syndrome. We here aimed to explore the possible link between host intestinal function, microbiota, and cardiac function in the ovariectomy (OVX) mouse model. Mice were ovariectomized to induce estrogen-related metabolic syndrome and cardiovascular defect. Microbiota was analyzed by 16s rRNA sequencing. miRNA and mRNA candidates expression were tested by qPCR. Cardiac function was examined by echocardiography. Colon specific delivery of miRNA candidates was achieved by oral gavage of Eudragit S100 functionalized microspheres. In comparison with the sham-operated group, OVX mice showed compromised cardiac function, together with activated inflammation in the visceral adipose tissue and heart. Lactobacillus abundance was significantly decreased in the gut of OVX mice. Meanwhile, miR-155 was mostly upregulated in the intestinal epithelium and thus the feces over other candidates, which in turn decreased Lactobacillus abundance in the intestine when endocytosed. Oral delivery of miR-155 antagonist restored the protective microbiota and thus protected the cardiac function in the OVX mice. This study has established a possible regulatory axis of intestinal miRNAs-microbiota-estrogen deficiency related phenotype in the OVX model. Colon specific delivery of therapeutic miRNAs would possibly restore the microbiota toward protective phenotype in the context of metabolic syndrome.
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Microbioma Gastrointestinal , Síndrome Metabólica , MicroRNAs , Animais , Colo/metabolismo , Estrogênios , Feminino , Humanos , Camundongos , MicroRNAs/genética , Fenótipo , RNA Ribossômico 16SRESUMO
A balanced detection of both adsorbates and dissolved species is very important for the clarification of the electrochemical reaction mechanism yet remains a major challenge for different modes of electrochemical infrared (IR) spectroscopy. Among others, conventional attenuated total reflection-surface-enhanced IR absorption spectroscopy (ATR-SEIRAS) is far less sensitive to low-concentration solution species than to surface species. We report herein an electrochemical wide-frequency ATR-SEIRAS with a novel thin-layer flow cell design, fulfilling the simultaneous detection of the variations of surface and solution species. This setup consists of a silicon wafer (with one side micromachined and the other side metallized), a thin-layer electrolyte structure with tunable thickness and flow rate, and a tilt-correction system based on laser collimation, enabling a well-controlled mass transport within the electrolyte layer and the spectral differentiation of solution species from adsorbates. Using acidic methanol oxidation on a Pt film electrode as a model system, besides SEIRA bands for adsorbed CO and formate intermediates, IR spectral signals for dissolved products CO2, formic acid, and methyl formate can be readily identified for a quiescent electrolyte layer of â¼20 µm, which are otherwise undetected with conventional ATR-SEIRAS, as indicated by the trend of spectral features with increasing thickness or flow rate.
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Eletrólitos , Eletroquímica , Eletrodos , Espectrofotometria Infravermelho/métodos , Propriedades de SuperfícieRESUMO
BACKGROUND: Carotid atherosclerosis by ultrasound scanning can be considered as an ideal window to reflect systemic artery atherosclerosis, which has aroused wide concern for predicting the severity of coronary artery atherosclerosis clinically. Ultrasound radio frequency (RF) data technology has enabled us to evaluate the carotid structure and elastic function precisely, for predicting the severity of coronary artery atherosclerosis. METHODS: Patients with suspected coronary artery disease (CAD) underwent coronary angiography and were assigned to four groups according to whether atherosclerotic plaque was found or not and it caused stenosis. Carotid artery intima-media thickness (IMT) and arterial stiffness were investigated by quality intima-media thickness (QIMT) and quality arterial stiffness (QAS) techniques during ultrasound scanning. Univariable and multivariable modeling were used to investigate correlations of carotid parameters to coronary artery atherosclerosis. Receive operating characteristic (ROC) curves were used to evaluate diagnostic performance of these ultrasound variables. RESULTS: Carotid IMT and stiffness variables pulse wave velocity (PWV), α, ß and compliance coefficient (CC) were statistically different between every two-group's comparisons. IMT correlated with stiffness variables significantly with r = 0.70, 0.77, 0.63, and -0.39, respectively. All variables correlated with the severity of coronary atherosclerosis with the odd ratio (OR) of 1.73, 1.67, 1.19, 1.23, and 0.56 accordingly as IMT, PWV, α, ß and CC were concerned. The AUC of IMT, PWV, α, ß and CC were 0.9257, 0.8910, 0.8016, 0.9383, 0.8581 with correctly classified rate of 88.16%, 83.77%, 78.07%, 86.84%, and 81.58%, respectively. CONCLUSIONS: Carotid artery IMT and stiffness variable PWV, α, ß and CC presented favorable predicting and differentiating values for patients with coronary atherosclerosis of different severity.
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Aterosclerose , Doença da Artéria Coronariana , Artérias Carótidas , Espessura Intima-Media Carotídea , Humanos , Análise de Onda de PulsoRESUMO
Developing high-performance electrocatalysts for the ethanol oxidation reaction (EOR) and the oxygen reduction reaction (ORR) is essential for the commercialization of direct ethanol fuel cells, but it is still formidably challenging. In this work, a novel Pd-Sb hexagonal nanoplate for boosting both cathodic and anodic fuel cell reactions is prepared. Detailed characterizations reveal that the nanoplates have ordered rhombohedral phase of Pd8 Sb3 (denoted as Pd8 Sb3 HPs). The Pd8 Sb3 HPs exhibit much enhanced activity toward the oxidation of various alcohols. Particularly, Pd8 Sb3 HPs/C displays superior specific and mass activities of 29.3 mA cm-2 and 4.5 A mgPd -1 toward the EOR, which are 7.0 and 11.3 times higher than those of commercial Pd/C, and 9.8 and 3.8 times higher than those of commercial Pt/C, respectively, representing one of the best EOR catalysts reported to date. In situ electrochemical attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) measurements reveal that Pd8 Sb3 HPs/C can effectively promote the C2 pathway of the EOR. As revealed by density functional theory calculations, the high EOR activity of the Pd8 Sb3 HPs can be ascribed to the reduced energy barrier of ethanol dehydrogenation. Additionally, Pd8 Sb3 HPs/C also shows superior performance in the ORR. This work advances the controllable synthesis of the Pd-Sb nanostructure, giving huge impetus for the design of high-efficiency electrocatalysts for energy conversion and beyond.