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The formation and preservation of the active phase of the catalysts at the triple-phase interface during CO2 capture and reduction is essential for improving the conversion efficiency of CO2 electroreduction toward value-added chemicals and fuels under operational conditions. Designing such ideal catalysts that can mitigate parasitic hydrogen generation and prevent active phase degradation during the CO2 reduction reaction (CO2RR), however, remains a significant challenge. Herein, we developed an interfacial engineering strategy to build a new SnOx catalyst by invoking multiscale approaches. This catalyst features a hierarchically nanoporous structure coated with an organic F-monolayer that modifies the triple-phase interface in aqueous electrolytes, substantially reducing competing hydrogen generation (less than 5%) and enhancing CO2RR selectivity (â¼90%). This rationally designed triple-phase interface overcomes the issue of limited CO2 solubility in aqueous electrolytes via proactive CO2 capture and reduction. Concurrently, we utilized pulsed square-wave potentials to dynamically recover the active phase for the CO2RR to regulate the production of C1 products such as formate and carbon monoxide (CO). This protocol ensures profoundly enhanced CO2RR selectivity (â¼90%) compared with constant potential (â¼70%) applied at -0.8 V (V vs RHE). We further achieved a mechanistic understanding of the CO2 capture and reduction processes under pulsed square-wave potentials via in situ Raman spectroscopy, thereby observing the potential-dependent intensity of Raman vibrational modes of the active phase and CO2RR intermediates. This work will inspire material design strategies by leveraging triple-phase interface engineering for emerging electrochemical processes, as technology moves toward electrification and decarbonization.
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Metabolic abnormalities are at the center of many diseases, and the capability to film and quantify the metabolic activities of a single cell is important for understanding the heterogeneities in these abnormalities. In this paper, a functional plasmonic microscope (FPM) is used to image and measure metabolic activities without fluorescent labels at a single-cell level. The FPM can accurately image and quantify the subnanometer membrane fluctuations with a spatial resolution of 0.5 µm in real time. These active cell membrane fluctuations are caused by metabolic activities across the cell membrane. A three-dimensional (3D) morphology of the bottom cell membrane was imaged and reconstructed with FPM to illustrate the capability of the microscope for cell membrane characterization. Then, the subnanometer cell membrane fluctuations of single cells were imaged and quantified with the FPM using HeLa cells. Cell metabolic heterogeneity is analyzed based on membrane fluctuations of each individual cell that is exposed to similar environmental conditions. In addition, we demonstrated that the FPM could be used to evaluate the therapeutic responses of metabolic inhibitors (glycolysis pathway inhibitor STF 31) on a single-cell level. The result showed that the metabolic activities significantly decrease over time, but the nature of this response varies, depicting cell heterogeneity. A low-concentration dose showed a reduced fluctuation frequency with consistent fluctuation amplitudes, while the high-concentration dose showcased a decreasing trend in both cases. These results have demonstrated the capabilities of the functional plasmonic microscope to measure and quantify metabolic activities for drug discovery.
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Corantes , Microscopia , Humanos , Células HeLa , Membrana Celular , MembranasRESUMO
We present a multi-channel delay sampling method to extend imaging depth in high-speed swept-source optical coherence tomography (SS-OCT). A balanced detector captures interference signals, converting them into electrical signals, which are then split into N channels, each with fixed time delays determined by the length of electrical cables. Then, they are digitized by an N-channel acquisition card. A calibration procedure is utilized to compensate for non-uniform phase shifts resulting from fixed time delays. The N-channel signals are merged in k-space and resampled to obtain a linearized spectrum, which increases the sampling rate by a factor of N, thereby extending the ranging distance by N times, all without altering k-clock triggering or sacrificing other imaging performance. The signal-to-noise ratio and sensitivity within the original depth range also have been enhanced. This advancement contributes to the improvement of the overall performance of SS-OCT systems.
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We report a high-speed, long-range, and wide-field swept-source optical coherence tomography (SS-OCT) system aimed for imaging microstructures and microcirculations in the oral cavity. This system operates at a scan speed of 600 kHz, delivering a wide imaging field of view at 42 × 42â mm2 and a ranging distance of 36 mm. To simultaneously meet the requirements of high speed and long range, it is necessary for the k-clock trigger signal to be generated at its maximum speed, which may induce non-linear phase response in electronic devices due to the excessive k-clock frequency bandwidth, leading to phase errors. To address this challenge, we introduced a concept of electrical dispersion and a global k-clock compensation approach to improve overall performance of the imaging system. Additionally, image distortion in the wide-field imaging mode is also corrected using a method based on distortion vector maps. With this system, we demonstrate comprehensive structural and blood flow imaging of the anterior oral cavity in healthy individuals. The high-speed, long-range, and wide-field SS-OCT system opens new opportunities for comprehensive oral cavity examinations and holds promise as a reliable tool for assessing oral health conditions.
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Supraglottic airway (SGA) is an alternative to endotracheal intubation, however endotracheal intubation is often essential. One method to convert from an SGA to an endotracheal tube (ETT) is utilizing the SGA as a conduit for fiberoptic-guided advancement of an Aintree catheter (airway exchange catheter), and exchange of the SGA for an ETT. In this prospective randomized study, we compared two SGA devices in facilitating this exchange. Subjects were randomized to receive either the i-gel® or LMA® Supreme™ SGA. The SGA was placed and an Aintree intubation catheter was inserted through the SGA over a fiberoptic bronchoscope. Next, the SGA was removed, leaving the Aintree within the trachea, and an ETT was placed over the Aintree catheter and advanced into the trachea. The i-gel group exhibited shorter time to successful intubation (median, 191 vs. 434 seconds; P = .002). The i-gel group also had fewer study subjects requiring more than one attempt for successful Aintree placement (33% vs. 75%, P = .02). The i-gel group showed superior laryngeal view score (LVS) (6 vs. 4; P = .003). The i-gel SGA achieved a faster time to successful intubation, higher rate of first attempt Aintree placement, and superior LVS.
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Tecnologia de Fibra Óptica , Intubação Intratraqueal , Máscaras Laríngeas , Humanos , Intubação Intratraqueal/instrumentação , Intubação Intratraqueal/métodos , Masculino , Estudos Prospectivos , Feminino , Pessoa de Meia-Idade , Adulto , Enfermeiros Anestesistas , IdosoRESUMO
BACKGROUND: Hospital readmission is common among patients with heart failure. Vulnerability to decline in physical function may increase the risk of noncardiovascular readmission for these patients, but the association between vulnerability and the cause of unplanned readmission is poorly understood, inhibiting the development of effective interventions. OBJECTIVES: We examined the association of vulnerability with the cause of readmission (cardiovascular vs. noncardiovascular) among hospitalized patients with acute decompensated heart failure. DESIGNS, SETTINGS, AND PARTICIPANTS: This prospective longitudinal study is part of the Vanderbilt Inpatient Cohort Study. MAIN OUTCOME AND MEASURES: The primary outcome was the cause of unplanned readmission (cardiovascular vs. noncardiovascular). The primary independent variable was vulnerability, measured using the Vulnerable Elders Survey (VES-13). RESULTS: Among 804 hospitalized patients with acute decompensated heart failure, 315 (39.2%) experienced an unplanned readmission within 90 days of discharge. In a multinomial logistic model with no readmission as the reference category, higher vulnerability was associated with readmission for noncardiovascular causes (relative risk ratio [RRR] = 1.36, 95% confidence interval [CI]: 1.06-1.75) in the first 90 days after discharge. The VES-13 score was not associated with readmission for cardiovascular causes (RRR = 0.94, 95% CI: 0.75-1.17). CONCLUSIONS: Vulnerability to functional decline predicted noncardiovascular readmission risk among hospitalized patients with heart failure. The VES-13 is a brief, validated, and freely available tool that should be considered in planning care transitions. Additional work is needed to examine the efficacy of interventions to monitor and mitigate noncardiovascular concerns among vulnerable patients with heart failure being discharged from the hospital.
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Insuficiência Cardíaca , Readmissão do Paciente , Humanos , Readmissão do Paciente/estatística & dados numéricos , Masculino , Feminino , Idoso , Estudos Prospectivos , Estudos Longitudinais , Idoso de 80 Anos ou mais , Fatores de Risco , Pessoa de Meia-Idade , HospitalizaçãoRESUMO
BACKGROUND: Adults hospitalized for cardiovascular events are at high risk for postdischarge mortality. Screening of psychosocial risk is prioritized by the Joint Commission. We tested whether key patient-reported psychosocial and behavioral measures could predict posthospitalization mortality in a cohort of adults hospitalized for a cardiovascular event. METHODS: We conducted a prospective cohort study to test the prognostic utility of validated patient-reported measures, including health literacy, social support, health behaviors and disease management, and socioeconomic status. Cox survival analyses of mortality were conducted over a median of 3.5 years. RESULTS: Among 2977 adults hospitalized for either acute coronary syndrome or acute decompensated heart failure, the mean age was 53 years, and 60% were male. After adjusting for demographic, clinical, and other psychosocial factors, mortality risk was greatest among patients who reported being unemployed (hazard ratio [HR]: 1.99, 95% confidence interval [CI]): 1.30-3.06), retired (HR: 2.14, 95% CI: 1.60-2.87), or unable to work due to disability (HR: 2.36, 95% CI: 1.73-3.21), as compared to those who were employed. Patient-reported perceived health competence (PHCS-2) and exercise frequency were also associated with mortality risk after adjusting for all other variables (HR: 0.86, 95% CI: 0.73-1.00 per four-point increase in PHCS-2; HR: 0.86, 95% CI: 0.77-0.96 per 3-day increase in exercise frequency, respectively). CONCLUSIONS: Patient-reported measures of employment status, perceived health competence, and exercise frequency independently predict mortality after a cardiac hospitalization. Incorporating these brief, valid measures into hospital-based screening may help with prognostication and targeting patients for resources during post-discharge transitions of care.