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A vertical-type InGaN light-emitting diode with a resonant cavity was demonstrated with a 9 µm aperture size and a short cavity formed by hybrid distributed Bragg reflectors (DBRs). The approach involved designing epitaxial structures and utilizing an electrochemical etching process to convert heavily doped n-type gallium nitride (n+-GaN) layers into porous GaN layers as a porous-GaN DBR structure. Thirteen pairs of the conductive porous-GaN:Si/GaN:Si DBR structure provided a vertical current path in a vertical-type light-emitting diodes (LED) structure. The LED epitaxial layers were separated from sapphire for membrane-type LED structures through a laser lift-off process. During the free-standing membrane fabrication process, the dielectric DBR deposited on ITO/p-GaN:Mg layers was inverted from top to bottom, thereby establishing the concept of higher reflectivity for the bottom DBR compared to the porous-GaN DBR. The physical cavity length was reduced from about 2.3 µm for the LED membrane to 0.74 µm for the membrane-type LED with the embedded porous-GaN DBR structure. The divergent angles and line width of EL emission light were reduced from 124°/31.7 nm to 44°/3.3 nm due to the resonant cavity effect. The membrane-type LED structures with hybrid DBRs consisted of small divergent angles, narrow line width, and vertical current injection properties that have potential for directional emission light sources and vertical-cavity surface-emitting diode laser applications.
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High channel current of the high electron mobility transistors (HEMTs) and high relative responsivity of the photodetectors (PDs) were demonstrated in the AlGaN/AlN/GaN channel-stacking epitaxial structures. The interference properties of the X-ray curves indicated high-quality interfaces of the conductive channels. The AlGaN/AlN/GaN interfaces were observed clearly in the transmission electron microscope micrograph. The saturation I ds currents of the HEMT structures were increased by adding a number of channels. The conductive properties of the channel-stacking structures corresponded to the peaks of the transconductance (g m) spectra in the HEMT structures. The depletion-mode one- and two-channel HEMT structures can be operated at the cutoff region by increasing the reverse V gs bias voltages. Higher I ds current in the active state and lower current in the cutoff state were observed in the two-channel HEMT structure compared with one- and three-channel HEMT structures. For the channel-stacking metal-semiconductor-metal photodetector structures, the peak responsivity was observed at almost 300 nm incident monochromic light, which was increased by adding a number of channel layers. The channel current of the HEMT devices and the photocurrent in the PD devices were increased by adding a number of two-dimensional electron gas (2DEG) channels. By using a flat gate metal layer, the two-channel AlGaN/AlN/GaN HEMT structures exhibited a high I ds current, a low cutoff current, and a high peak g m value and have the potential for GaN-based power devices, fast portable chargers, and ultraviolet PD applications.
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Background and Objectives: An elevated heart rate is an independent risk factor for cardiovascular disease; however, the relationship between heart rate control and the long-term outcomes of patients with heart failure with reduced ejection fraction (HFrEF) remains unclear. This study explored the long-term prognostic importance of heart rate control in patients hospitalized with HFrEF. Materials and Methods: We retrieved the records of patients admitted for decompensated heart failure with a left ventricular ejection fraction (LVEF) of ≤40%, from 1 January 2005 to 31 December 2019. The primary outcome was a composite of cardiovascular death or hospitalization for heart failure (HHF) during follow-up. We analyzed the outcomes using Cox proportional hazard ratios calculated using the patients' heart rates, as measured at baseline and approximately 3 months later. The mean follow-up duration was 49.0 ± 38.1 months. Results: We identified 5236 eligible patients, and divided them into five groups on the basis of changes in their heart rates. The mean LVEFs of the groups ranged from 29.1% to 30.6%. After adjustment for all covariates, the results demonstrated that lesser heart rate reductions at the 3-month screening period were associated with long-term cardiovascular death, HHF, and all-cause mortality (p for linear trend = 0.033, 0.042, and 0.003, respectively). The restricted cubic spline model revealed a linear relationship between reduction in heart rate and risk of outcomes (p for nonlinearity > 0.2). Conclusions: Greater reductions in heart rate were associated with a lower risk of long-term cardiovascular death, HHF, and all-cause mortality among patients discharged after hospitalization for decompensated HFrEF.
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Insuficiencia Cardíaca , Disfunción Ventricular Izquierda , Humanos , Volumen Sistólico/fisiología , Función Ventricular Izquierda/fisiología , Frecuencia Cardíaca , Pronóstico , HospitalizaciónRESUMEN
Ultraviolet-C AlGaN resonant-cavity light-emitting diodes with top and bottom pipe-AlGaN-distributed Bragg reflectors (DBRs) have been demonstrated. For the top/bottom DBR structures, 20 pairs of n+-AlGaN:Si/n-AlGaN:Si stack structures were transformed into the pipe-AlGaN:Si/n-AlGaN:Si DBRs through a doping-selective electrochemical wet etching process. The reflectivity of the pipe-AlGaN DBR structure was measured as 90% at 276.7 nm with a 20.9 nm flat stopband width. The anisotropic optical properties of the pipe-AlGaN DBR structure had been analyzed through the polarization-dependent reflectance spectra. For temperature-dependent reflectance spectra, the central wavelengths were slightly redshifted from 275 nm (100 K) to 281 nm (600 K) due to thermal expansion, refractive index increase, and partial strain release phenomena in the pipe-DBR structure. High photoluminescence emission intensity and line-width reducing phenomena were observed at 10 K in the UVC-LED with the resonant-cavity structure, which has potential for high-efficiency UV-C light source applications.
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BACKGROUND: We established 1-h and 1-day survival models after terminal extubation to optimize ventilator use and achieve a balance between critical care for COVID-19 and hospice medicine. METHODS: Data were obtained from patients with end-of-life status at terminal extubation from 2015 to 2020. The associations between APACHE II scores and parameters with survival time were analyzed. Parameters with a p-value ≤ 0.2 in univariate analysis were included in multivariate models. Cox proportional hazards regression analysis was used for the multivariate analysis of survival time at 1 h and 1 day. RESULTS: Of the 140 enrolled patients, 76 (54.3%) died within 1 h and 35 (25%) survived beyond 24 h. No spontaneous breathing trial (SBT) within the past 24 h, minute ventilation (MV) ≥ 12 L/min, and APACHE II score ≥ 25 were associated with shorter survival in the 1 h regression model. Lower MV, SpO2 ≥ 96% and SBT were related to longer survival in the 1-day model. Hospice medications did not influence survival time. CONCLUSION: An APACHE II score of ≥ 25 at 1 h and SpO2 ≥ 96% at 1 day were strong predictors of disposition of patients to intensivists. These factors can help to objectively tailor pathways for post-extubation transition and rapidly allocate intensive care unit resources without sacrificing the quality of palliative care in the era of COVID-19. Trial registration They study was retrospectively registered. IRB No.: 202101929B0.
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COVID-19 , Hospitales para Enfermos Terminales , Humanos , Extubación Traqueal , Pandemias , COVID-19/epidemiología , Unidades de Cuidados Intensivos , Cuidados Críticos , Respiración ArtificialAsunto(s)
Antipsicóticos , Trastorno Depresivo Mayor , Trastornos Psicóticos , Retención Urinaria , Antipsicóticos/efectos adversos , Trastorno Depresivo Mayor/tratamiento farmacológico , Humanos , Trastornos Psicóticos/tratamiento farmacológico , Risperidona/efectos adversos , Retención Urinaria/inducido químicamenteRESUMEN
Atorvastatin 40 mg (ATOR 40) and ezetimibe 10 mg/simvastatin 20 mg (EZ-SIM 20) have similar reductions of low-density lipoprotein cholesterol (LDL-C) but cardiovascular (CV) outcomes between these two therapies are unclear. Our real-world cohort study is to test the hypothesis of pleiotropic effects of purely higher dose statin on CV outcomes beyond similar reductions of LDL-C, especially for extremely CV risk patients. Between January 1, 2007 and December 31, 2013, a total of 3,372 patients with type 2 diabetes mellitus (T2DM) admitted due to acute coronary syndrome (ACS) or acute ischemic stroke (AIS) were selected as the study cohort from the Taiwan National Health Insurance Research Database. Clinical outcomes were evaluated by ATOR 40 group (n = 1686) matched with EZ-SIM 20 group (n = 1686). Primary composite outcome includes CV death, non-fatal myocardial infarction, and non-fatal stroke. Secondary composite outcome includes hospitalization for unstable angina (HUA), percutaneous coronary intervention (PCI), and coronary artery bypass grafting (CABG). With a mean follow-up of 2.4 years, no significant difference of primary composite outcome was observed between ATOR 40 and EZ-SIM 20 groups (subdistribution hazard ratio [SHR], 1.09; 95% confidence interval [CI], 0.95-1.25). Nevertheless, ATOR 40 group had lower risks of HUA (SHR, 0.50; 95% CI, 0.35-0.72), PCI (SHR, 0.82; 95% CI, 0.69-0.97) and CABG (SHR, 0.62; 95% CI, 0.40-0.97) than EZ-SIM 20 group. For T2DM patients after ACS or AIS, ATOR 40 and EZ-SIM 20 had similar major CV outcomes, which still supported the main driver for CV risk reductions is LDL-C lowering.
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Aterosclerosis/tratamiento farmacológico , Aterosclerosis/etiología , Diabetes Mellitus Tipo 2/complicaciones , Combinación Ezetimiba y Simvastatina/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Anticolesterolemiantes/administración & dosificación , Anticolesterolemiantes/uso terapéutico , Aterosclerosis/diagnóstico , Aterosclerosis/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Combinación Ezetimiba y Simvastatina/administración & dosificación , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Masculino , Persona de Mediana Edad , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND: Cardiac troponins are important markers for diagnosis of acute myocardial infarction (AMI) in general population; however, chronically-elevated troponins levels are often seen in patients with renal insufficiency, which reduce their diagnostic accuracy. The aim of our study was to access the diagnostic values of initial high-sensitive cardiac troponin T (hs-cTnT) and relative change of hs-cTnT for AMI in patients with and without renal insufficiency. METHODS: Cardiac care unit patients with elevated hs-cTnT levels in 2017-2018 were enrolled. Receiver operating characteristic (ROC) curves were used to evaluate initial hs-cTnT levels and relative changes after 3 h of enrollment for diagnosis of AMI in patients with estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 (low), and eGFR ≥ 60 mL/min/1.73 m2 (normal). RESULTS: Of 359 patients, 240 patients had low eGFR, and 119 patients had normal eGFR. The area under the ROC curve (AUC) for the initial hs-cTnT levels was 0.58 (95% CI, 0.5-0.65, p = 0.053) among patients with low eGFR and 0.54 (95% CI, 0.4-0.67, p = 0.612) among patients with normal eGFR. AUCs for relative changes of hs-cTnT were 0.82 (95% CI, 0.76-0.88, p < 0.001) in patients with low eGFR and 0.82 (95% CI, 0.71-0.91, p < 0.001) in patients with normal eGFR. Optimal cutoff values for the relative changes in hs-cTnT were 16% and 12% in patients with low eGFR and normal eGFR, respectively. CONCLUSIONS: Relative changes in hs-cTnT levels had better diagnostic accuracy than initial hs-cTnT levels.
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Infarto del Miocardio/complicaciones , Infarto del Miocardio/metabolismo , Insuficiencia Renal/complicaciones , Troponina T/metabolismo , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Biomarcadores/metabolismo , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/fisiopatología , Estudios Prospectivos , Curva ROCRESUMEN
BACKGROUND: Data is limited on baseline left atrial (LA) myocardial mechanics between apical hypertrophic cardiomyopathy (ApHCM) patients who develop non-valvular atrial fibrillation (NVAF) during follow-up and those who do not. METHODS: This retrospective study investigated the clinical outcomes of consecutive patients newly diagnosed with ApHCM between August 2011 and July 2014 who were followed-up for at least 3 years. The patients underwent 12-lead surface electrocardiography and/or 24-hour Holter electrocardiography at least once a year. The patients were divided into two groups, namely those who did or did not exhibit NVAF during follow-up, respectively. The baseline clinical and echocardiographic data of the two groups were compared. RESULTS: Twenty patients were studied, five of whom were lost to follow-up. Of the remaining 15 ApHCM patients, seven developed NVAF. No differences were observed in the clinical characteristics of the two groups. However, for the echocardiographic data, the NVAF development group exhibited a larger LA volume and impaired LA reservoir, conduit and booster functions. The NVAF development group also showed lower peak LA strain and stiffer left atrium. The LA volume, function, global strain and stiffness were all statistically associated with NVAF development. Among these parameters, a LA conduit function of ≤ 24.9% was found to be the best parameter to discriminate NVAF development. CONCLUSIONS: The baseline LA function was impaired in the ApHCM patients who subsequently developed NVAF during follow-up. A LA conduit function of ≤ 24.9% was strongly associated with NVAF development.
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Despite III-V semiconductors demonstrating extraordinary solar-to-hydrogen (STH) conversion efficiencies, high cost and poor stability greatly impede their practical implementation in photoelectrochemical (PEC) water splitting applications. Here, we present a simple and efficient strategy for III-V-based photoelectrodes that functionally and spatially decouples the light harvesting component of the device from the electrolysis part that eliminates parasitic light absorption, reduces the cost, and enhances the stability without any compromise in efficiency. The monolithically integrated PEC cell was fabricated by an epitaxial lift-off and transfer of inversely grown InGaP/GaAs to a robust Ni-substrate and the resultant photoanode exhibits an STH efficiency of ~9% with stability ~150 h. Moreover, with the ability to access both sides of the device, we constructed a fully-integrated, unassisted-wireless "artificial leaf" system with an STH efficiency of ~6%. The excellent efficiency and stability achieved herein are attributed to the light harvesting/catalysis decoupling scheme, which concurrently improves the optical, electrical, and electrocatalytic characteristics.
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The integration of III-V and Si multi-junction solar cells as photovoltaic devices has been studied in order to achieve high photovoltaic conversion efficiency. However, large differences in the coefficients of thermal expansion and the lattice parameters of GaAs, Si, and InGaAs have made it difficult to obtain high-efficiency solar cells grown as epilayers on Si and InP substrates. In this paper, two types of devices, including GaInP/GaAs stacked on Si (GaInP/GaAs//Si) and GaInP/GaAs stacked on InGaAs (GaInP/GaAs//InGaAs), are fabricated via mechanical stacking and wire bonding technologies. Mechanically stacked GaInP/GaAs//Si and GaInP/GaAs//InGaAs triple-junction solar cells are prepared via glue bonding. Current-voltage measurements of the two samples are made at room temperature. The short-circuit current densities of the GaInP/GaAs//Si and GaInP/GaAs//InGaAs solar cells are 13.37 and 13.66 mA/cm2, while the open-circuit voltages of these two samples are measured to be 2.71 and 2.52 V, respectively. After bonding the GaInP/GaAs dual-junction with the Si and InGaAs solar cells, the conversion efficiency is relatively improved by 32.6% and 30.9%, respectively, compared to the efficiency of the GaInP/GaAs dual-junction solar cell alone. This study demonstrates the high potential of combining mechanical stacked with wire bonding and ITO films to achieve high conversion efficiency in solar cells with three or more junctions.
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RATIONALE: Although transient reduction in the left ventricular ejection fraction is characteristic of Takotsubo cardiomyopathy, little is known about the time-course changes of myocardial deformation in coronary vasospasm-related Takotsubo cardiomyopathy. PATIENT CONCERNS: We retrospectively analyzed the time-course changes in left ventricle, right ventricle, and left atrium strain values in a patient with coronary vasospasm-related Takotsubo cardiomyopathy. We found that not only left ventricular strain but also left atrial strain was abnormal during acute Takotsubo cardiomyopathy due to coronary vasospasm. Right ventricular free wall strain was normal. DIAGNOSES: Coronary vasospasm-related Takotsubo cardiomyopathy. INTERVENTIONS: A serial echocardiographic study. OUTCOMES: The left ventricular strain was still subnormal despite a normalized left ventricular ejection fraction 2 months later. The left atrial strain was normal when the left ventricular ejection fraction normalized. LESSONS: From this limited experience, it is suggested that echocardiographic myocardial deformation analysis can provide more information than the standard ejection fraction in evaluating myocardial contractile function.
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Vasoespasmo Coronario/diagnóstico por imagen , Ecocardiografía/métodos , Cardiomiopatía de Takotsubo/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen , Anciano de 80 o más Años , Función del Atrio Izquierdo/fisiología , Vasoespasmo Coronario/complicaciones , Vasoespasmo Coronario/fisiopatología , Femenino , Corazón/diagnóstico por imagen , Corazón/fisiopatología , Humanos , Estudios Retrospectivos , Volumen Sistólico , Cardiomiopatía de Takotsubo/etiología , Cardiomiopatía de Takotsubo/fisiopatología , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular Izquierda/fisiologíaRESUMEN
INTRODUCTION: Little is known about the time-course changes in left ventricular myocardial deformation in patients with Takotsubo cardiomyopathy (TC) using layer-specific quantification of myocardial deformation assessed by 2-dimensional speckle tracking echocardiography (2DSTE). CASE SUMMARY: In this retrospective 2DSTE follow-up study of 3 female patients with sepsis-induced TC, we examined changes in strain among the 3 myocardial layers, and examined the changes in left ventricular diastolic function and right ventricular systolic function. In all 3 patients, there was improvement of at least 15% in left ventricular ejection fractions, and improvement in left ventricular longitudinal and circumferential strains. The absolute differences in left ventricular global strains between the endocardium and epicardium, and between the first and the third 2DSTE studies reflect the following: a decrease in all 3 myocardial layers in patients with acute TC; and a slower improvement in mid-myocardial and epicardial function during recovery of TC. In addition, the right ventricular free wall strains were also impaired in the acute stage of TC with gradual improvement during recovery. CONCLUSIONS: Left ventricular strains did not fully recover even 1 month after acute TC. In addition, right ventricular free wall strains were also impaired in all 3 patients initially. In this case series, we found that layer-specific 2DSTE is a more sensitive method for myocardial function assessment than standard echocardiography.
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Ecocardiografía , Miocardio/patología , Sepsis/complicaciones , Cardiomiopatía de Takotsubo/etiología , Cardiomiopatía de Takotsubo/patología , Anciano , Anciano de 80 o más Años , Ecocardiografía/métodos , Femenino , Estudios de Seguimiento , Humanos , Estudios RetrospectivosRESUMEN
Renin inhibitors enhance endothelial nitric oxide synthase (eNOS) bioavailability and have protective effects on endothelial function and atherosclerotic changes. This study was designed to investigate whether aliskiren attenuates the effects of interleukin-6 (IL-6) on eNOS and the eNOS-caveolin-1 interaction in human aortic endothelial cells (HAECs). In this study, we examined the effects of pretreatment with aliskiren on the changes of IL-6-induced expression and activation of eNOS and caveolin-1 in cultured HAECs. IL-6 inhibited and aliskiren increased the phosphorylation of eNOS at Ser1177; however, eNOS protein and mRNA expression were not changed. Pretreatment with aliskiren attenuated the inhibitory effects of IL-6 on eNOS phosphorylation and nitric oxide production. IL-6 increased the phosphorylation of caveolin-1 at Tyr14 without affecting the caveolin-1 protein and mRNA expression. Pretreatment with aliskiren attenuated the effects of IL-6 on caveolin-1 phosphorylation. The binding of eNOS and caveolin-1, as determined by a co-immunoprecipitation assay, was increased by IL-6 treatment and decreased by aliskiren pretreatment. Furthermore, treatment with short interfering RNA of the extracellular signal-regulated kinase gene reversed the effects of IL-6 and aliskiren on eNOS and caveolin-1. In conclusion, aliskiren attenuates the inhibitory effects of IL-6 on eNOS phosphorylation and nitric oxide production and IL-6 induced caveolin-1 phosphorylation. In addition, aliskiren reverses the effects of IL-6 on the eNOS-caveolin-1 interaction.
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Amidas/farmacología , Aorta/citología , Caveolina 1/metabolismo , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Fumaratos/farmacología , Óxido Nítrico Sintasa de Tipo III/metabolismo , Células Cultivadas , Humanos , Transducción de Señal/efectos de los fármacosRESUMEN
In this study, the thin-film vertical-type AlGaInP LEDs on Cu substrates were fabricated. By performing the epitaxial lift-off (ELO) process, the LED device can be transferred from GaAs to Cu substrate. Then the GaAs substrate was separated and the ELO-LED was completed. To overcome the drawback of crack formation in the epilayer during the ELO process, various patterned Cu substrates were designed. Moreover, the finite element method was used to simulate the stress distribution in the LED sample during the ELO process. From the simulation results, an optimum structure of patterned Cu substrate was obtained since its maximum stress can be confined to the chip edges and the stress was decreased significantly during the ELO process, resulting in an apparent reduction of crack generation after separating the GaAs substrate. This optimum patterned Cu substrate was employed for the fabrication of ELO-LED. In addition, the chemical etching process was also used to etch the GaAs substrate, and this device transferred to Cu substrate was denoted as CE-LED. Based on the measurements of device performances, the forward voltages (@350 mA) of the CE-LED and ELO-LED were measured to be 2.20 and 2.29 V, while the output powers (@350 mA) of these two devices were 49.9 and 48.2 mW, respectively. Furthermore, the surface temperatures (@350 mA) of these two samples were 46.9-48.3 and 45.2-47.0 °C, respectively. Obviously, the device characteristics of the ELO-LED are very similar to those of the CE-LED. It confirms that the design of patterned Cu substrate is very helpful to obtain the thin-film vertical-type AlGaInP LEDs. Additionally, via the ELO process, the separated GaAs substrate can be reused for production cost down.