RESUMEN
We report an electro-optic isolator fabricated on thin-film lithium niobate by photolithography-assisted chemo-mechanical etching that shows an isolation of 39.50â dB and an overall fiber-to-fiber loss of 2.6â dB.
RESUMEN
We demonstrate on-chip coherent beam combination of two waveguide amplifiers on Er3+-doped thin film lithium niobate (Er:TFLN) platform. Our device is built based on an electro-optic modulator fabricated on Er:TFLN. The output power of the coherently combined amplifiers is measured as high as 12.9â mW, surpassing that of previous single waveguide amplifiers based on an Er3+-doped thin film lithium niobate platform.
RESUMEN
Heart failure with preserved ejection fraction (HFpEF) is defined as HF with left ventricular ejection fraction (LVEF) not less than 50%. HFpEF accounts for more than 50% of all HF patients, and its prevalence is increasing year to year with the aging population, with its prognosis worsening. The clinical assessment of cardiac function and prognosis in patients with HFpEF remains challenging due to the normal range of LVEF and the nonspecific symptoms and signs. In recent years, new echocardiographic techniques have been continuously developed, particularly speckle-tracking echocardiography (STE), which provides a sensitive and accurate method for the comprehensive assessment of cardiac function and prognosis in patients with HFpEF. Therefore, this article reviewed the clinical utility of STE in patients with HFpEF.
RESUMEN
Semantic segmentation, which is a fundamental task in computer vision. Every pixel will have a specific semantic class assigned to it through semantic segmentation methods. Embedded systems and mobile devices are difficult to deploy high-accuracy segmentation algorithms. Despite the rapid development of semantic segmentation, the balance between speed and accuracy must be improved. As a solution to the above problems, we created a cross-scale fusion attention mechanism network called CFANet, which fuses feature maps from different scales. We first design a novel efficient residual module (ERM), which applies both dilation convolution and factorized convolution. Our CFANet is mainly constructed from ERM. Subsequently, we designed a new multi-branch channel attention mechanism (MCAM) to refine the feature maps at different levels. Experiment results show that CFANet achieved 70.6% mean intersection over union (mIoU) and 67.7% mIoU on Cityscapes and CamVid datasets, respectively, with inference speeds of 118 FPS and 105 FPS on NVIDIA RTX2080Ti GPU cards with 0.84M parameters.
RESUMEN
Right ventricular-pulmonary artery coupling (RV-PA coupling) refers to the relationship between RV contractility and RV afterload. Normal RV-PA coupling is maintained only when RV function and pulmonary vascular resistance are appropriately matched. RV-PA uncoupling occurs when RV contractility cannot increase to match RV afterload, resulting in RV dysfunction and right heart failure. RV-PA coupling plays an important role in the pathophysiology and progression of cardiovascular diseases. Therefore, early and accurate evaluation of RV-PA coupling is of great significance for a patient's condition assessment, clinical decision making, risk stratification, and prognosis judgment. RV-PA coupling can be assessed by using invasive or noninvasive approaches. The aim of this review was to summarize the pathological mechanism and evaluation methods of RV-PA coupling, the advantages and disadvantages of each method, and the application value of RV-PA coupling in various cardiovascular diseases.
RESUMEN
Myocardial fibrosis (MF) is a non-reversible process that occurs following acute or chronic myocardial damage. MF worsens myocardial deformation, remodels the heart and raises myocardial stiffness, and is a crucial pathological manifestation in patients with end-stage cardiovascular diseases and closely related to cardiac adverse events. Therefore, early quantitative analysis of MF plays an important role in risk stratification, clinical decision, and improvement in prognosis. With the advent and development of strain imaging modalities in recent years, MF may be detected early in cardiovascular diseases. This review summarizes the clinical usefulness of strain imaging techniques in the non-invasive assessment of MF.
RESUMEN
Pulmonary regurgitation usually leads to right heart dilatation and eventually right heart dysfunction, which is associated with a poor prognosis. Transcatheter pulmonary valve replacement is a developing treatment for pulmonary valve dysfunction that can take the place of traditional surgery and make up for the shortcomings of a large injury. Echocardiography plays a significant role in assessing ventricular function; however, conventional echocardiographic parameters have several limitations. Speckle tracking echocardiography has been regarded as a more accurate tool for quantifying cardiac function than conventional echocardiography. Therefore, the aim of this review was to summarize the application of speckle tracking echocardiography for evaluating right and left ventricular functions in patients after transcatheter pulmonary valve replacement.
RESUMEN
Heart failure (HF) is an extremely major health problem with gradually increasing incidence in developed and developing countries. HF may lead to cardiac remodeling; thus, advanced imaging techniques are required to comprehensively evaluate cardiac mechanics. Recently, three-dimensional speckle-tracking echocardiography (3D-STE) has been developed as a novel imaging technology that is based on the three-dimensional speckle-tracking on the full volume three-dimensional datasets. Three-dimensional speckle-tracking echocardiography allows a more accurate evaluation of global and regional myocardial performance, assessment of cardiac mechanics, detection of subclinical cardiac dysfunction, and prediction of adverse clinical events in a variety of cardiovascular diseases. Therefore, this review summarizes the clinical usefulness of 3D-STE in patients with HF.
RESUMEN
Objectives: Both right ventricular free wall longitudinal strain (RVFWLS) and right ventricular global longitudinal strain (RVGLS) using two-dimensional speckle tracking echocardiography (2D-STE) has been demonstrated to predict adverse outcomes in patients with repaired tetralogy of Fallot (r-TOF). However, RVGLS may be affected by left ventricular (LV) function owing to the fact that the interventricular septum is also a part of the left ventricle. Therefore, the aim of our study was to compare the predictive value of RVFWLS with that of RVGLS in patients with r-TOF. Materials and methods: A total of 179 patients with r-TOF were included in this study. RVFWLS, RVGLS, and left ventricle global longitudinal strain (LVGLS) were evaluated by 2D-STE. The adverse clinical events were death or r-TOF-related rehospitalization. Prognostic performance was evaluated by C-statistic and Akaike information criterion (AIC). Results: Thirty-one patients developed poor outcomes during a median follow-up period of 2.8 years. Compared with patients without end-point events, those with end-point events had higher incidence of moderate/severe pulmonary regurgitation, larger right heart sizes, and lower RV fractional area change (RVFAC), RVFWLS, RVGLS, and LVGLS than those without. Multivariate Cox regression analysis revealed that RVFAC, RVFWLS, RVGLS, and LVGLS were predictive of poor outcomes in patients with r-TOF after adjustment for transannular patch and QRS duration. A Cox model using RVFWLS (C index = 0.876, AIC = 228) was found to predict unfavorable outcomes more accurately than a model with RVGLS (C index = 0.856, AIC = 243), RVFAC (C index = 0.811, AIC = 248), and LVGLS (C index = 0.830, AIC = 248). Conclusion: Although both RVGLS and RVFWLS are associated with adverse events, RVFWLS provides superior prognostic value than that of RVGLS in patients with r-TOF.
RESUMEN
Primary cardiac tumors (PCTs) are rare, with benign PCTs being relatively common in approximately 75% of all PCTs. Benign PCTs are usually asymptomatic, and they are found incidentally by imaging. Even if patients present with symptoms, they are usually nonspecific. Before the application of imaging modalities to the heart, our understanding of these tumors is limited to case reports and autopsy studies. The advent and improvement of various imaging technologies have enabled the non-invasive evaluation of benign PCTs. Although echocardiography is the most commonly used imaging examination, it is not the best method to describe the histological characteristics of tumors. At present, cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT) are often used to assess benign PCTs providing detailed information on anatomical and tissue features. In fact, each imaging modality has its own advantages and disadvantages, multimodality imaging uses two or more imaging types to provide valuable complementary information. With the widespread use of multimodality imaging, these techniques play an indispensable role in the management of patients with benign PCTs by providing useful diagnostic and prognostic information to guide treatment. This article reviews the multimodality imaging characterizations of common benign PCTs.
RESUMEN
Background: Although the left atrium (LA) plays a key role in the pathophysiology and disease progression of heart failure with preserved ejection fraction (HFpEF), the impact of type 2 diabetes mellitus (T2DM) on LA function and stiffness in HFpEF patients remains unclear. Furthermore, the prognostic value of different phases of LA function and stiffness is less well-established in HFpEF patients. Methods: This study prospectively enrolled 164 HFpEF patients who were in sinus rhythm at the time of echocardiography, including 61 (37%) HFpEF patients with T2DM. LA reservoir, conduit, and pump function were assessed using two-dimensional volume indices and speckle tracking echocardiography. The LA stiffness was calculated as the ratio of early mitral inflow velocity-to-early annular tissue velocity (E/e') and LA reservoir function. The primary end point was a combined outcome of heart failure hospitalization or death. Results: Left atrium reservoir function [measured by peak LA strain (LAS-peak)] and LA pump function (measured by LAS-active) remained significantly lower in the HFpEF patients with T2DM compared with those without T2DM, even after adjustment for potential confounders. In addition, the LA stiffness of HFpEF patients with T2DM was higher than those without T2DM. After a median follow-up of 13.7 months, 46 patients (28.1%) reached the composite end point. LAS-peak (hazard ratios: 0.88; 95% confidence interval: 0.81-0.95; P = 0.001) was significantly associated with the risk of heart failure hospitalization or death after adjusting for demographic and clinical characteristics, LV global longitudinal strain, E/e', and LA volume index. In contrast, other LA function and stiffness parameters did not independently predict the risk of adverse events. Kaplan-Meier analysis showed that HFpEF patients with T2DM and low LAS-peak (<27.2%) had a significantly increased risk of heart failure-related hospitalization or death (log-rank P < 0.001). Conclusion: Left atrium reservoir and pump function are impaired, whereas LA stiffness is increased in HFpEF patients with T2DM compared with those without T2DM. LAS-peak is a powerful predictor of adverse clinical outcomes and may be crucial for risk stratification in HFpEF patients with and without T2DM.
RESUMEN
Atrial fibrillation (AF) is the most common arrhythmia with significant morbidity and mortality. Exacerbated by the aging population, the prevalence of AF is gradually increasing. Accurate evaluation of structure and function of left atrium (LA) has important prognostic significance in patients with AF. Echocardiography is the imaging technique of first choice to assess LA structure and function due to its better availability, accessibility and safety over cardiac computed tomography and cardiac magnetic resonance. Therefore, the aim of this review is to summarize the recent research progress of evaluating LA size by three-dimensional echocardiography and LA function by speckle tracking echocardiography (STE) in predicting the occurrence and recurrence of AF and determining the risk of stroke in AF. In addition, we summarized the role of traditional echocardiography in detecting AF patients that are at high risk of heart failure or cardiovascular death.
RESUMEN
1,3,5-Tri(10H-phenothiazin-10-yl)benzene (3PTZ) is endowed with unique redox and photoresponsive characteristics and has been utilized as a p-type redox center for organic battery cathode material and a room-temperature phosphorescence (RTP) material, respectively. Conversely, its exploration in other research fields, particularly organic synthesis, remains unknown. Here, we demonstrate that 3PTZ-POP synthesized via cross-linking of 3PTZ is capable of harvesting visible-light photons and selectively converting solar energy to chemical energy. Specifically, 3PTZ-POP functions as a metal-free and recyclable photocatalyst to promote the sequential C(sp2)-H functionalizations of N-arylacrylamides with readily available trifluoromethylsulfonyl chloride as the radical precursor. An array of 3,3-disubstituted 2-oxindoles bearing a pharmaceutically important CF3 moiety are delivered in moderate to excellent yields under mild and sustainable conditions.
RESUMEN
Integrated thin-film lithium niobate (LN) electro-optic (EO) modulators of broad bandwidth, low insertion loss, low cost and high production rate are essential elements in contemporary interconnection industries and disruptive applications. Here, we demonstrated the design and fabrication of a high performance thin-film LN EO modulator using photolithography assisted chemo-mechanical etching (PLACE) technology. Our device shows a 3-dB bandwidth over 50 GHz, along with a comparable low half wave voltage-length product of 2.16 Vcm and a fiber-to-fiber insertion loss of 2.6 dB. The PLACE technology supports large footprint, high fabrication uniformity, competitive production rate and extreme low device optical loss simultaneously, our result shows promising potential for developing high-performance large-scale low-loss photonic integrated devices.
RESUMEN
Patients with heart failure (HF) have high morbidity and mortality. Accurate assessment of right ventricular (RV) function has important prognostic significance in patients with HF. However, conventional echocardiographic parameters of RV function have limitations in RV assessments due to the complex geometry of right ventricle. In recent years, speckle tracking echocardiography (STE) has been developed as promising imaging technique to accurately evaluate RV function. RV longitudinal strain (RVLS) using STE, as a sensitive index for RV function evaluation, displays the powerfully prognostic value in patients with HF. Therefore, the aim of the present review was to summarize the utility of RVLS in patients with HF.